WorldWideScience

Sample records for methane mitigation potentials

  1. Mitigating global warming potentials of methane and nitrous oxide gases from rice paddies under different irrigation regimes.

    Science.gov (United States)

    Ali, Muhammad Aslam; Hoque, M Anamul; Kim, Pil Joo

    2013-04-01

    A field experiment was conducted in Bangladesh Agricultural University Farm to investigate the mitigating effects of soil amendments such as calcium carbide, calcium silicate, phosphogypsum, and biochar with urea fertilizer on global warming potentials (GWPs) of methane (CH4) and nitrous oxide (N2O) gases during rice cultivation under continuous and intermittent irrigations. Among the amendments phosphogypsum and silicate fertilizer, being potential source of electron acceptors, decreased maximum level of seasonal CH4 flux by 25-27 % and 32-38 % in continuous and intermittent irrigations, respectively. Biochar and calcium carbide amendments, acting as nitrification inhibitors, decreased N2O emissions by 36-40 % and 26-30 % under continuous and intermittent irrigations, respectively. The total GWP of CH4 and N2O gases were decreased by 7-27 % and 6-34 % with calcium carbide, phosphogypsum, and silicate fertilizer amendments under continuous and intermittent irrigations, respectively. However, biochar amendments increased overall GWP of CH4 and N2O gases.

  2. Review of methane mitigation technologies with application to rapid release of methane from the Arctic.

    Science.gov (United States)

    Stolaroff, Joshuah K; Bhattacharyya, Subarna; Smith, Clara A; Bourcier, William L; Cameron-Smith, Philip J; Aines, Roger D

    2012-06-19

    Methane is the most important greenhouse gas after carbon dioxide, with particular influence on near-term climate change. It poses increasing risk in the future from both direct anthropogenic sources and potential rapid release from the Arctic. A range of mitigation (emissions control) technologies have been developed for anthropogenic sources that can be developed for further application, including to Arctic sources. Significant gaps in understanding remain of the mechanisms, magnitude, and likelihood of rapid methane release from the Arctic. Methane may be released by several pathways, including lakes, wetlands, and oceans, and may be either uniform over large areas or concentrated in patches. Across Arctic sources, bubbles originating in the sediment are the most important mechanism for methane to reach the atmosphere. Most known technologies operate on confined gas streams of 0.1% methane or more, and may be applicable to limited Arctic sources where methane is concentrated in pockets. However, some mitigation strategies developed for rice paddies and agricultural soils are promising for Arctic wetlands and thawing permafrost. Other mitigation strategies specific to the Arctic have been proposed but have yet to be studied. Overall, we identify four avenues of research and development that can serve the dual purposes of addressing current methane sources and potential Arctic sources: (1) methane release detection and quantification, (2) mitigation units for small and remote methane streams, (3) mitigation methods for dilute (methane streams, and (4) understanding methanotroph and methanogen ecology.

  3. SCREENING APPROACHES FOR METHANE MITIGATING POTENTIAL OF TANNIN-CONTAINING PLANTS UNDER IN VITRO RUMEN ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    A. Jayanegara

    2014-10-01

    Full Text Available The aim of the present study was to conduct univariate, bivariate and multivariate (principalcomponent analysis, PCA approaches in the screening of tannin-containing plants from variouscollection sites for their CH4 mitigating properties. Plant samples were obtained from various collectionsites in different countries, i.e. Indonesia (n = 27 species, Mongolia (n = 14, Switzerland (n = 16 andGermany (n = 3. The plants were incubated in vitro with buffered-rumen fluid at 39oC for 24 h. Totalgas production was recorded as an indicator of feed quality and emission of CH4 was measured. Resultsshowed that, based on bivariate screening, generally, plants possessed low CH4 production had lowquality or low total gas production except Rhus typhina, i.e. 43 ml/200 mg DM. The loading plot of PCAshowed that all phenolic fractions were in the opposite direction with CH4 and total gas production.Plants clustered together in reverse direction to that of CH4 were Bergenia crassifolia root and leaf,Swietenia mahagoni, Clidemia hirta, Peltiphyllum peltatum, Acacia villosa and R. typhina. It wasconluded that, for tannin-containing plants, screenings based on univariate, bivariate and multivariateapproaches in relation to ruminal CH4 emission led to similar results.

  4. SCREENING APPROACHES FOR METHANE MITIGATING POTENTIAL OF TANNIN-CONTAINING PLANTS UNDER IN VITRO RUMEN ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    A. Jayanegara

    2012-12-01

    Full Text Available The aim of the present study was to conduct univariate, bivariate and multivariate (principal component analysis, PCA approaches in the screening of tannin-containing plants from various collection sites for their CH4 mitigating properties. Plant samples were obtained from various collection sites in different countries, i.e. Indonesia (n = 27 species, Mongolia (n = 14, Switzerland (n = 16 and Germany (n = 3. The plants were incubated in vitro with buffered-rumen fluid at 39oC for 24 h. Total gas production was recorded as an indicator of feed quality and emission of CH4 was measured. Results showed that, based on bivariate screening, generally, plants possessed low CH4 production had low quality or low total gas production except Rhus typhina, i.e. 43 ml/200 mg DM. The loading plot of PCA showed that all phenolic fractions were in the opposite direction with CH4 and total gas production. Plants clustered together in reverse direction to that of CH4 were Bergenia crassifolia root and leaf, Swietenia mahagoni, Clidemia hirta, Peltiphyllum peltatum, Acacia villosa and R. typhina. It was conluded that, for tannin-containing plants, screenings based on univariate, bivariate and multivariate approaches in relation to ruminal CH4 emission led to similar results

  5. CYANOBACTERIA FOR MITIGATING METHANE EMISSION FROM SUBMERGED PADDY FIELDS

    Energy Technology Data Exchange (ETDEWEB)

    Upasana Mishra; Shalini Anand [Department of Environmental Studies, Inderprastha Engineering College, Sahibabad, Ghaziabad (India)

    2008-09-30

    Atmospheric methane, a potent greenhouse gas with high absorption potential for infrared radiation, is responsible for one forth of the total anticipated warming. It is forming a major part of green house gases, next after carbon dioxide. Its concentration has been increasing alarmingly on an average at the rate of one percent per year. Atmospheric methane, originating mainly from biogenic sources such as paddy fields, natural wetlands and landfills, accounts for 15-20% of the world's total anthropogenic methane emission. With intensification of rice cultivation in coming future, methane emissions from paddy fields are anticipated to increase. India's share in world's rice production is next after to China and likewise total methane emission from paddy fields also. Methane oxidation through planktophytes, particularly microalgae which are autotrophic and abundant in rice rhizospheres, hold promise in controlling methane emission from submerged paddy fields. The present study is focused on the role of nitrogen fixing, heterocystous cyanobacteria and Azolla (a water fern harboring a cyanobacterium Anabaena azollae) as biological sink for headspace concentration of methane in flooded soils. In this laboratory study, soil samples containing five potent nitrogen fixer cyanobacterial strains from paddy fields, were examined for their methane reducing potential. Soil sample without cyanobacterial strain was tested and taken as control. Anabaena sp. was found most effective in inhibiting methane concentration by 5-6 folds over the control. Moist soil cores treated with chemical nitrogen, urea, in combination with cyanobacteria mixture, Azolla microphylla or cyanobacteria mixture plus Azolla microphylla exhibited significance reduction in the headspace concentration of methane than the soil cores treated with urea alone. Contrary to other reports, this study also demonstrates that methane oxidation in soil core samples from paddy fields was stimulated by

  6. Factors Affecting Mitigation of Methane Emission from Ruminants: Management Strategies

    Directory of Open Access Journals (Sweden)

    Afshar Mirzaei-Aghsaghali

    2015-06-01

    Full Text Available Nowadays, greenhouse gas emission which results in elevating global temperature is an important subject of worldwide ecological and environmental concern. Among greenhouse gases, methane is considered a potent greenhouse gas with 21 times more global warming potential than carbon dioxide. Worldwide, ruminant livestock produce about 80 million metric tons of methane each year, accounting for about 28% of global emissions from human related activities. Therefore it is impelling animal scientists to finding solutions to mitigate methane emission from ruminants. It seems that solutions can be discussed in four topics including: nutrition (feeding, biotechnology, microbiology and management strategies. We have already published the first review article on feeding strategies. In the current review, management strategies such as emphasizing on animals - type and individual variability, reducing livestock numbers, improving animal productivity and longevity as well as pasture management; that can be leads to decreasing methane production from ruminant animal production are discussed.

  7. Timelines for mitigating methane emissions from energy technologies

    CERN Document Server

    Roy, Mandira; Trancik, Jessika E

    2015-01-01

    Energy technologies emitting differing proportions of methane and carbon dioxide vary in their relative climate impacts over time, due to the different atmospheric lifetimes of the two gases. Standard technology comparisons using the global warming potential (GWP) emissions equivalency metric do not reveal these dynamic impacts, and may not provide the information needed to assess technologies and emissions mitigation opportunities in the context of broader climate policy goals. Here we formulate a portfolio optimization model that incorporates changes in technology impacts as a radiative forcing (RF) stabilization target is approached. An optimal portfolio, maximizing allowed energy consumption while meeting the RF target, is obtained by year-wise minimization of the marginal RF impact in an intended stabilization year. The optimal portfolio calls for using certain higher methane-emitting technologies prior to an optimal switching year, followed by methane-light technologies as the stabilization year approac...

  8. Mitigation of methane and nitrous oxide emissions from animal operations: I. A review of enteric methane mitigation options

    NARCIS (Netherlands)

    Hristov, A.N.; Oh, J.; Firkins, J.; Dijkstra, J.; Kebreab, E.; Waghorn, G.; Makkar, H.P.S.; Adesogan, A.T.; Yang, W.; Lee, C.; Gerber, P.J.; Henderson, B.L.; Tricarico, J.M.

    2013-01-01

    The goal of this review was to analyze published data related to mitigation of enteric methane (CH4) emissions from ruminant animals to document the most effective and sustainable strategies. Increasing forage digestibility and digestible forage intake was one of the major recommended CH4 mitigation

  9. Mitigation of methane and nitrous oxide emissions from animal operations: I. A review of enteric methane mitigation options

    NARCIS (Netherlands)

    Hristov, A.N.; Oh, J.; Firkins, J.; Dijkstra, J.; Kebreab, E.; Waghorn, G.; Makkar, H.P.S.; Adesogan, A.T.; Yang, W.; Lee, C.; Gerber, P.J.; Henderson, B.L.; Tricarico, J.M.

    2013-01-01

    The goal of this review was to analyze published data related to mitigation of enteric methane (CH4) emissions from ruminant animals to document the most effective and sustainable strategies. Increasing forage digestibility and digestible forage intake was one of the major recommended CH4 mitigation

  10. Methane Tracking and Mitigation Options - EPA CMOP

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset contains the sub-model for EPA's MARKAL model, which tracks methane emissions from the energy system, and limited other sources (landfills and manure...

  11. Reduction of methane emission from landfills using bio-mitigation systems – from lab tests to full scale implementation

    DEFF Research Database (Denmark)

    Kjeldsen, Peter; Scheutz, Charlotte

    , or open or closed bed biofilter systems. The objective of this paper is to describe the relationship between research on process understanding of the oxidation of landfill gas contained methane and the up-scale to full bio-mitigation systems implemented at landfills. The oxidation of methane is controlled...... due to self-heating processes. Bio-mitigation can be used as a stand-alone technology or combined with active or passive gas collection. When implementing bio-mitigation systems focus should be on additional fugitive methane emissions or the presence of uncontrolled point releases. A protocol...... for implementing a bio-mitigation system is presented, and the reported landfill-implemented bio-mitigation systems either established as full-scale or pilot-scale systems are reviewed. It is concluded that bio-mitigation systems have a large potential for providing cost-efficient mitigation options for reducing...

  12. Gradient packing bed bio-filter for landfill methane mitigation.

    Science.gov (United States)

    Obulisamy, Parthiba Karthikeyan; Sim Yan May, Jane; Rajasekar, Balasubramanian

    2016-10-01

    We assessed the suitability of various biogenic materials for development of a gradient packed bed bio-filter to mitigate the methane (CH4) emission from landfills. Five different biogenic materials (windrow compost-WC; vermicompost-VC; landfill top cover-LTC; landfill bottom soil-LBS; and river soil sediment-SS) were screened. Among these materials, the VC showed a better CH4 oxidation potential (MOP) of 12.6μg CH4 gdw(-1)h(-1). Subsequently, the VC was used as a packing material along with wood chips in proto-type bio-filters. Wood chips were mixed at 5-15% to form three distinct gradients in a test bio-filter. Under the three different CH4 loading rates of 33, 44 and 55 gCH4 m(-3)h(-1), the achieved MOPs were 31, 41, and 47gCH4 m(-3)h(-1), respectively. The gradient packed bed bio-filter is effective for landfill CH4 mitigation than the conventional bio-filter as the latter shows gas channeling effects with poor MOPs.

  13. Handbook methane potential; Handbok metanpotential

    Energy Technology Data Exchange (ETDEWEB)

    Carlsson, My (AnoxKaldnes AB (Sweden)); Schnurer, Anna (Swedish Univ. of Agricultural Sciences, Uppsala (Sweden))

    2011-07-15

    Before using a organic material for biogas production it is essential to evaluate the methane production potential. The methane potential is one important tool possible to use during planning of new plants but also when new materials are considered for already running biogas plants. The chemical composition of different organic material varies extensively and this will have an impact on both the degradability and the methane potential. Information about the methane potential of a specific material can sometimes be found in the literature or can be calculated after a chemical/ physical or biological characterization. Here, the BMP test (Biochemical Methane Potential) is a commonly used method. Today the BMP test is a commonly used method to determine the methane potential. Many national and international research groups, consultants as well as personal at biogas plants are using this method and there is a lot of data available in the literature from such tests. In addition there are several protocols giving guidelines on how to execute a BMP-test. The BMP-test is performed in many different ways, not always under optimized conditions, and there is a lack of information on how to interpret the obtained data. This report summarizes knowledge from the literature and the experience from a Swedish referee group, consisting of persons being active performers of BMP-tests. The report does not include a standardized protocol as the procedure can be performed in different ways depending on available equipment and on the type of material to be tested. Instead the report discusses different factors of great importance for a successful test giving reliable results. The report also summarizes important information concerning the interpretation and how to present results in order to allow comparison of data from different test.

  14. Potential methane reservoirs beneath Antarctica.

    Science.gov (United States)

    Wadham, J L; Arndt, S; Tulaczyk, S; Stibal, M; Tranter, M; Telling, J; Lis, G P; Lawson, E; Ridgwell, A; Dubnick, A; Sharp, M J; Anesio, A M; Butler, C E H

    2012-08-30

    Once thought to be devoid of life, the ice-covered parts of Antarctica are now known to be a reservoir of metabolically active microbial cells and organic carbon. The potential for methanogenic archaea to support the degradation of organic carbon to methane beneath the ice, however, has not yet been evaluated. Large sedimentary basins containing marine sequences up to 14 kilometres thick and an estimated 21,000 petagrams (1 Pg equals 10(15) g) of organic carbon are buried beneath the Antarctic Ice Sheet. No data exist for rates of methanogenesis in sub-Antarctic marine sediments. Here we present experimental data from other subglacial environments that demonstrate the potential for overridden organic matter beneath glacial systems to produce methane. We also numerically simulate the accumulation of methane in Antarctic sedimentary basins using an established one-dimensional hydrate model and show that pressure/temperature conditions favour methane hydrate formation down to sediment depths of about 300 metres in West Antarctica and 700 metres in East Antarctica. Our results demonstrate the potential for methane hydrate accumulation in Antarctic sedimentary basins, where the total inventory depends on rates of organic carbon degradation and conditions at the ice-sheet bed. We calculate that the sub-Antarctic hydrate inventory could be of the same order of magnitude as that of recent estimates made for Arctic permafrost. Our findings suggest that the Antarctic Ice Sheet may be a neglected but important component of the global methane budget, with the potential to act as a positive feedback on climate warming during ice-sheet wastage.

  15. Biofiltration for Mitigation of Methane Emission from Animal Husbandry

    NARCIS (Netherlands)

    Melse, R.W.; Werf, van der A.W.

    2005-01-01

    Removal of methane from exhaust air of animal houses and manure storage has a large potential for the reduction of greenhouse gas emissions from animal husbandry. The aim of this study was to design a biofilter for methane removal at a full-scale livestock production facility. Air from the headspace

  16. Biofiltration for Mitigation of Methane Emission from Animal Husbandry

    NARCIS (Netherlands)

    Melse, R.W.; Werf, van der A.W.

    2005-01-01

    Removal of methane from exhaust air of animal houses and manure storage has a large potential for the reduction of greenhouse gas emissions from animal husbandry. The aim of this study was to design a biofilter for methane removal at a full-scale livestock production facility. Air from the headspace

  17. Methane mitigation timelines to inform energy technology evaluation

    Science.gov (United States)

    Roy, Mandira; Edwards, Morgan R.; Trancik, Jessika E.

    2015-11-01

    Energy technologies emitting differing proportions of methane (CH4) and carbon dioxide (CO2) vary significantly in their relative climate impacts over time, due to the distinct atmospheric lifetimes and radiative efficiencies of the two gases. Standard technology comparisons using the global warming potential (GWP) with a fixed time horizon do not account for the timing of emissions in relation to climate policy goals. Here we develop a portfolio optimization model that incorporates changes in technology impacts based on the temporal proximity of emissions to a radiative forcing (RF) stabilization target. An optimal portfolio, maximizing allowed energy consumption while meeting the RF target, is obtained by year-wise minimization of the marginal RF impact in an intended stabilization year. The optimal portfolio calls for using certain higher-CH4-emitting technologies prior to an optimal switching year, followed by CH4-light technologies as the stabilization year approaches. We apply the model to evaluate transportation technology pairs and find that accounting for dynamic emissions impacts, in place of using the static GWP, can result in CH4 mitigation timelines and technology transitions that allow for significantly greater energy consumption while meeting a climate policy target. The results can inform the forward-looking evaluation of energy technologies by engineers, private investors, and policy makers.

  18. In-vitro screening of Kalahari browse species for rumen methane mitigation

    Directory of Open Access Journals (Sweden)

    Jacobus Johannes Francois Theart

    2015-12-01

    Full Text Available The nutritional value of browse foliage from the Thorny Kalahari Dune Bush veld of South Africa is not characterized. Most of this browse species is rich in tannin, but still palatable, and is consumed by ruminants during the dry season, as well as having a role to play in mitigating enteric methane emission from ruminants. In this study, the rumen methane mitigation potential of 19 browse species foliage collected from the Thorny Kalahari Dune Bush veld, was analyzed in terms of chemical composition, in vitro fermentation, digestibility and methane production. In vitro gas and methane production and organic matter digestibility (IVOMD were determined by using rumen fluid collected, strained and anaerobically prepared. A semi-automated system was used to measure gas production (GP from each browse species by incubating 400 mg samples in a shaking incubator at 39 °C with or without inclusion of 400 mg of polyethylene glycol (PEG. Data for all the parameters collected were statistically analyzed using the SAS (9.0 general linear model (GLM procedure, and differences between foliage species were determined using Duncan’s multiple-range test. Acacia luederitziiand Monechma incanumshowed the best potential for decreasing methane production by up to 90 % after 48 h of incubation. The secondary components (mainly tannins of the browse species appeared to have a significant effect on volatile fatty acids (VFA, methane and gas production as judged by the comparison of samples incubated with or without PEG inclusion. The substantial amount of crude protein (CP content coupled with their anti-methanogenic effect during fermentation would make these browses a potential mitigation option for small scale farmers and pastoralists in sub-Sahara Africa. However, it is also very important that systematic and strategic supplementation in a mixed diet should be looked at as the way forward in terms of best utilization.

  19. Factors affecting mitigation of methane emission from ruminants: Microbiology and biotechnology strategies

    Directory of Open Access Journals (Sweden)

    Afshar Mirzaei

    2015-12-01

    Full Text Available Climate change is a subject of global environmental concern. Increased anthropogenic Greenhouse Gas (GHG emissions have increased the global temperature the last 100 to 200 years. Carbon dioxide and methane are the main greenhouse gases related to animal nutrition and methane has greater global warming potential than carbon dioxide. Among greenhouse gases, methane is considered a potent greenhouse gas with 21 times more global warming potential than carbon dioxide. Worldwide, ruminant livestock produce about 80 million metric tons of methane each year, accounting for about 28% of global emissions from human related activities. Therefore it is impelling animal scientists to finding solutions to mitigate methane emission from ruminants. It seems that solutions can be discussed in four topics including: nutrition (feeding, biotechnology, microbiology and management strategies. We have already published the first and second review articles on feeding strategies and management strategies. In the current review, Microbiology and biotechnology such as emphasizing on animal  breeding, genetic merit, bovine somatotropin (BST, unproductive animals, vaccination, immunisation and biological control (bacteriophage, acetogenesis reductive, chemical defaunation that can be leads to decreasing methane production from ruminant animal production are discussed.

  20. Microbial methane oxidation processes and technologies for mitigation of landfill gas emissions

    DEFF Research Database (Denmark)

    Scheutz, Charlotte; Kjeldsen, Peter; Bogner, J.E.;

    2009-01-01

    utilizing oxygen that diffuses into the cover layer from the atmosphere. The methane oxidation process, which is governed by several environmental factors, can be exploited in engineered systems developed for methane emission mitigation. Mathematical models that account for methane oxidation can be used...... to predict methane emissions from landfills. Additional research and technology development is needed before methane mitigation technologies utilizing microbial methane oxidation processes can become commercially viable and widely deployed.......Landfill gas containing methane is produced by anaerobic degradation of organic waste. Methane is a strong greenhouse gas and landfills are one of the major anthropogenic sources of atmospheric methane. Landfill methane may be oxidized by methanotrophic microorganisms in soils or waste materials...

  1. Design and evaluation of a porous burner for the mitigation of anthropogenic methane emissions.

    Science.gov (United States)

    Wood, Susie; Fletcher, David F; Joseph, Stephen D; Dawson, Adrian; Harris, Andrew T

    2009-12-15

    Methane constitutes 15% of total global anthropogenic greenhouse gas emissions. The mitigation of these emissions could have a significant near-term effect on slowing global warming, and recovering and burning the methane would allow a wasted energy resource to be exploited. The typically low and fluctuating energy content of the emission streams makes combustion difficult; however porous burners-an advanced combustion technology capable of burning low-calorific value fuels below the conventional flammability limit-are one possible mitigation solution. Here we discuss a pilot-scale porous burner designed for this purpose. The burner comprises a cylindrical combustion chamber filled with a porous bed of alumina saddles, combined with an arrangement of heat exchanger tubes for preheating the incoming emission stream. A computational fluid dynamics model was developed to aid in the design process. Results illustrating the burner's stable operating range and behavior are presented: stable ultralean combustion is demonstrated at natural gas concentrations as low as 2.3 vol%, with transient combustion at concentrations down to 1.1 vol%; the system is comparatively stable to perturbations in the operating conditions, and emissions of both carbon monoxide and unburned hydrocarbons are negligible. Based on this pilot-scale demonstration, porous burners show potential as a methane mitigation technology.

  2. Investigating the effect of two methane-mitigating diets on the rumen microbiome using massively parallel sequencing.

    Science.gov (United States)

    Ross, E M; Moate, P J; Marett, L; Cocks, B G; Hayes, B J

    2013-09-01

    methane-mitigating diets have altered the rumen microbiome toward naturally low methane-emitting microbial profiles. The contig sequences are predominantly new and include Faecalibacterium spp. The contigs we have identified here are potential biomarkers for low-methane-emitting cattle.

  3. GHG emissions and mitigation potential in Indian agriculture

    Science.gov (United States)

    Vetter, Sylvia; Feliciano, Diana; Sapkota, Tek; Hillier, Jon; Smith, Pete; Stirling, Clare

    2016-04-01

    India is one of the world's largest greenhouse gas (GHG) emitter, accounting for about 5% of global emissions with further increases expected in the future. The Government of India aims to reduce emission intensities by 20-25% by 2020 compared with the 2005 level. In a recent departure from past practice the reconvened Council on Climate Change stated that climate change in agriculture would include a component that would focus on reducing emissions in agriculture, particularly methane and nitrous oxide emissions. To develop recommendations for mitigation in agriculture in India, a baseline study is presented to analyse the GHG emissions from agriculture for current management (Directorate of Economics and Statistics of the government of India). This analysis is done for the two states Bihar and Haryana, which differ in their management and practises based on different climate and policies. This first analysis shows were the highest GHG emissions in agriculture is produced and were the highest mitigation potential might be. The GHG emissions and mitigation potential are calculated using the CCAFS Mitigation Option Tool (CCAFS-MOT) (https://ccafs.cgiar.org/mitigation-option-tool-agriculture#.VpTnWL826d4) with modifications for the special modelling. In a second step, stakeholder meetings provided a wide range of possible and definite scenarios (management, policy, technology, costs, etc.) for the future to mitigate emissions in agriculture as well as how to increase productivity. These information were used to create scenarios to give estimates for the mitigation potential in agriculture for India in 2020.

  4. Understanding the nature of methane emission from rice ecosystems as basis of mitigation strategies

    Energy Technology Data Exchange (ETDEWEB)

    Buendia, L.V.; Neue, H.U.; Wassmann, R. [International Rice Research Institute, Laguna (Philippines)] [and others

    1996-12-31

    Methane is considered as an important Greenhouse gas and rice fields are one of the major atmospheric methane sources. The paper aims to develop sampling strategies and formulate mitigation options based on diel (day and night) and seasonal pattern of methane emission. The study was conducted in 4 countries to measure methane flux using an automatic closed chamber system. A 24-hour bihourly methane emissions were continuously obtained during the whole growing season. Daily and seasonal pattern of methane fluxes from different rice ecosystems were evaluated. Diel pattern of methane emission from irrigated rice fields, in all sites, displayed similar pattern from planting to flowering. Fluxes at 0600, 1200, and 1800 h were important components of the total diel flux. A proposed sampling frequency to accurately estimate methane emission within the growing season was designed based on the magnitude of daily flux variation. Total methane emission from different ecosystems follow the order: deepwater rice > irrigated rice > rainfed rice. Application of pig manure increased total emission by 10 times of that without manure. Green manure application increased emission by 49% of that applied only with inorganic fertilizer. Removal of floodwater at 10 DAP and 35 DAP, within a period of 4 days, inhibited production and emission of methane. The level of variation in daily methane emission and seasonal emission pattern provides useful information for accurate determination of methane fluxes. Characterization of seasonal emission pattern as to ecologies, fertilizer amendments, and water management gives an idea of where to focus mitigation strategies for sustainable rice production.

  5. The Use of Plant Bioactive Compounds to Mitigate Enteric Methane in Ruminants and its Application in Indonesia

    Directory of Open Access Journals (Sweden)

    Elizabeth Wina

    2012-03-01

    Full Text Available Worldwide, increasing greenhouse gas (GHG emissions have become a major concern as they are now considered to be the cause of global warming. Several strategies have been planned and taken by different countries including Indonesia to mitigate this situation. Agriculture is considered to be one of major contributors to GHG, especially methane coming from ruminant digestive processes. More than 85% of the methane produced by ruminants comes from enteric fermentation. Several options have been proposed to lower this enteric methane production. This paper describes a review on diet manipulation using feed additives, especially plant bioactive compounds, to mitigate the GHG emission from ruminant livestock. Plant bioactive compounds have been found with various chemical structures. Some of them such as saponin, tannin, essential oils, organosulphur compounds, have been reported to have ability to reduce enteric methane production. Indonesia has many plant resources that have potential as methane reducing agents. Sapindus rarak fruit especially its methanol extract contain saponins which reduce the activity of methanogens in the rumen in vitro, hence reduce methane production (11%. Feeding S. rarak to sheep increased daily weight gain but not that of local cattle. Shrub legumes such as Calliandra calothyrsus and Leucaena leucocephala contain tannins which can reduce methanogenesis (3 – 21% methane reduction. Besides tannin, these shrub legumes are a good source of protein. Feeding shrub legumes can be beneficial as a protein source and a methane reducer. Other sources of methane reducing agents have been tested in other countries and some can be applied for Indonesian situation. The strategy to reduce methane by plant bioactive compounds should be developed to be simple and relatively cheap so it will benefit the local farmers. Extraction of these compounds may be expensive, therefore, costs should be considered carefully when proposing to use the

  6. Coal-packed methane biofilter for mitigation of green house gas emissions from coal mine ventilation air.

    Science.gov (United States)

    Limbri, Hendy; Gunawan, Cindy; Thomas, Torsten; Smith, Andrew; Scott, Jason; Rosche, Bettina

    2014-01-01

    Methane emitted by coal mine ventilation air (MVA) is a significant greenhouse gas. A mitigation strategy is the oxidation of methane to carbon dioxide, which is approximately twenty-one times less effective at global warming than methane on a mass-basis. The low non-combustible methane concentrations at high MVA flow rates call for a catalytic strategy of oxidation. A laboratory-scale coal-packed biofilter was designed and partially removed methane from humidified air at flow rates between 0.2 and 2.4 L min-1 at 30°C with nutrient solution added every three days. Methane oxidation was catalysed by a complex community of naturally-occurring microorganisms, with the most abundant member being identified by 16S rRNA gene sequence as belonging to the methanotrophic genus Methylocystis. Additional inoculation with a laboratory-grown culture of Methylosinus sporium, as investigated in a parallel run, only enhanced methane consumption during the initial 12 weeks. The greatest level of methane removal of 27.2±0.66 g methane m-3 empty bed h-1 was attained for the non-inoculated system, which was equivalent to removing 19.7±2.9% methane from an inlet concentration of 1% v/v at an inlet gas flow rate of 1.6 L min-1 (2.4 min empty bed residence time). These results show that low-cost coal packing holds promising potential as a suitable growth surface and contains methanotrophic microorganisms for the catalytic oxidative removal of methane.

  7. Coal-packed methane biofilter for mitigation of green house gas emissions from coal mine ventilation air.

    Directory of Open Access Journals (Sweden)

    Hendy Limbri

    Full Text Available Methane emitted by coal mine ventilation air (MVA is a significant greenhouse gas. A mitigation strategy is the oxidation of methane to carbon dioxide, which is approximately twenty-one times less effective at global warming than methane on a mass-basis. The low non-combustible methane concentrations at high MVA flow rates call for a catalytic strategy of oxidation. A laboratory-scale coal-packed biofilter was designed and partially removed methane from humidified air at flow rates between 0.2 and 2.4 L min-1 at 30°C with nutrient solution added every three days. Methane oxidation was catalysed by a complex community of naturally-occurring microorganisms, with the most abundant member being identified by 16S rRNA gene sequence as belonging to the methanotrophic genus Methylocystis. Additional inoculation with a laboratory-grown culture of Methylosinus sporium, as investigated in a parallel run, only enhanced methane consumption during the initial 12 weeks. The greatest level of methane removal of 27.2±0.66 g methane m-3 empty bed h-1 was attained for the non-inoculated system, which was equivalent to removing 19.7±2.9% methane from an inlet concentration of 1% v/v at an inlet gas flow rate of 1.6 L min-1 (2.4 min empty bed residence time. These results show that low-cost coal packing holds promising potential as a suitable growth surface and contains methanotrophic microorganisms for the catalytic oxidative removal of methane.

  8. Coal-Packed Methane Biofilter for Mitigation of Green House Gas Emissions from Coal Mine Ventilation Air

    Science.gov (United States)

    Limbri, Hendy; Gunawan, Cindy; Thomas, Torsten; Smith, Andrew; Scott, Jason; Rosche, Bettina

    2014-01-01

    Methane emitted by coal mine ventilation air (MVA) is a significant greenhouse gas. A mitigation strategy is the oxidation of methane to carbon dioxide, which is approximately twenty-one times less effective at global warming than methane on a mass-basis. The low non-combustible methane concentrations at high MVA flow rates call for a catalytic strategy of oxidation. A laboratory-scale coal-packed biofilter was designed and partially removed methane from humidified air at flow rates between 0.2 and 2.4 L min−1 at 30°C with nutrient solution added every three days. Methane oxidation was catalysed by a complex community of naturally-occurring microorganisms, with the most abundant member being identified by 16S rRNA gene sequence as belonging to the methanotrophic genus Methylocystis. Additional inoculation with a laboratory-grown culture of Methylosinus sporium, as investigated in a parallel run, only enhanced methane consumption during the initial 12 weeks. The greatest level of methane removal of 27.2±0.66 g methane m−3 empty bed h−1 was attained for the non-inoculated system, which was equivalent to removing 19.7±2.9% methane from an inlet concentration of 1% v/v at an inlet gas flow rate of 1.6 L min−1 (2.4 min empty bed residence time). These results show that low-cost coal packing holds promising potential as a suitable growth surface and contains methanotrophic microorganisms for the catalytic oxidative removal of methane. PMID:24743729

  9. Designing better methane mitigation policies: the challenge of distributed small sources in the natural gas sector

    Science.gov (United States)

    Ravikumar, Arvind P.; Brandt, Adam R.

    2017-04-01

    Methane—a short-lived and potent greenhouse gas—presents a unique challenge: it is emitted from a large number of highly distributed and diffuse sources. In this regard, the United States’ Environmental Protection Agency (EPA) has recommended periodic leak detection and repair surveys at oil and gas facilities using optical gas imaging technology. This regulation requires an operator to fix all detected leaks within a set time period. Whether such ‘find-all-fix-all’ policies are effective depends on significant uncertainties in the character of emissions. In this work, we systematically analyze the effect of facility-related and mitigation-related uncertainties on regulation effectiveness. Drawing from multiple publicly-available datasets, we find that: (1) highly-skewed leak-size distributions strongly influence emissions reduction potential; (2) variations in emissions estimates across facilities leads to large variability in mitigation effectiveness; (3) emissions reductions from optical gas imaging-based leak detection programs can range from 15% to over 70%; and (4) while implementation costs are uniformly lower than EPA estimates, benefits from saved gas are highly variable. Combining empirical evidence with model results, we propose four policy options for effective methane mitigation: performance-oriented targets for accelerated emission reductions, flexible policy mechanisms to account for regional variation, technology-agnostic regulations to encourage adoption of the most cost-effective measures, and coordination with other greenhouse gas mitigation policies to reduce unintended spillover effects.

  10. Special topics--Mitigation of methane and nitrous oxide emissions from animal operations: I. A review of enteric methane mitigation options.

    Science.gov (United States)

    Hristov, A N; Oh, J; Firkins, J L; Dijkstra, J; Kebreab, E; Waghorn, G; Makkar, H P S; Adesogan, A T; Yang, W; Lee, C; Gerber, P J; Henderson, B; Tricarico, J M

    2013-11-01

    The goal of this review was to analyze published data related to mitigation of enteric methane (CH4) emissions from ruminant animals to document the most effective and sustainable strategies. Increasing forage digestibility and digestible forage intake was one of the major recommended CH4 mitigation practices. Although responses vary, CH4 emissions can be reduced when corn silage replaces grass silage in the diet. Feeding legume silages could also lower CH4 emissions compared to grass silage due to their lower fiber concentration. Dietary lipids can be effective in reducing CH4 emissions, but their applicability will depend on effects on feed intake, fiber digestibility, production, and milk composition. Inclusion of concentrate feeds in the diet of ruminants will likely decrease CH4 emission intensity (Ei; CH4 per unit animal product), particularly when inclusion is above 40% of dietary dry matter and rumen function is not impaired. Supplementation of diets containing medium to poor quality forages with small amounts of concentrate feed will typically decrease CH4 Ei. Nitrates show promise as CH4 mitigation agents, but more studies are needed to fully understand their impact on whole-farm greenhouse gas emissions, animal productivity, and animal health. Through their effect on feed efficiency and rumen stoichiometry, ionophores are likely to have a moderate CH4 mitigating effect in ruminants fed high-grain or mixed grain-forage diets. Tannins may also reduce CH4 emissions although in some situations intake and milk production may be compromised. Some direct-fed microbials, such as yeast-based products, might have a moderate CH4-mitigating effect through increasing animal productivity and feed efficiency, but the effect is likely to be inconsistent. Vaccines against rumen archaea may offer mitigation opportunities in the future although the extent of CH4 reduction is likely to be small and adaptation by ruminal microbes and persistence of the effect is unknown

  11. National and Sectoral GHG Mitigation Potential

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    This paper compares model estimates of national and sectoral GHG mitigation potential across six key OECD GHG-emitting economies: Australia, Canada, the EU, Japan, Mexico and the US. It examines the implications of model structure, baseline and policy assumptions, and assesses GHG mitigation potential estimates across a variety of models, including models that are used to inform climate policy-makers in each of these economies.

  12. Mitigation of methane and nitrous oxide emissions from animal operations: II. A review of manure management mitigation options

    NARCIS (Netherlands)

    Montes, F.; Meinen, R.; Dell, C.; Rotz, A.; Hristov, A.N.; Oh, J.; Waghorn, G.; Gerber, P.J.; Henderson, B.L.; Makkar, H.P.S.; Dijkstra, J.

    2013-01-01

    This review analyzes published data on manure management practices used to mitigate methane (CH4) and nitrous oxide (N2O) emissions from animal operations. Reducing excreted nitrogen (N) and degradable organic carbon (C) by diet manipulation to improve the balance of nutrient inputs with production

  13. Mitigation options for methane emissions from rice fields in the Philippines

    Energy Technology Data Exchange (ETDEWEB)

    Lantin, R.S.; Buendia, L.V.; Wassmann, R. [International Rice Research Institute, Laguna (Philippines)] [and others

    1996-12-31

    The contribution of Philippine rice production to global methane emission and breakthroughs in methane emission studies conducted in the country are presented in this paper. A significant impact in the reduction of GHG emissions from agriculture can be achieved if methane emissions from ricefields can be abated. This study presents the contribution of Philippine rice cultivation to global methane emission and breakthroughs in methane emission studies in the country which address the issue of mitigation. Using the derived emission factors from local measurements, rice cultivation contributes 566.6 Gg of methane emission in the Philippines. This value is 62% of the total methane emitted from the agriculture sector. The emission factors employed which are 78% of the IPCC value for irrigated rice and 95% for rainfed rice were derived from measurements with an automatic system taken during the growth duration in the respective ecosystems. Plots drained for 2 weeks at midtillering and before harvest gave a significant reduction in methane emission as opposed to continuously flooded plots and plots drained before harvest. The cultivar Magat reduced methane emission by 50% as compared to the check variety IR72. The application of ammonium sulfate instead of urea reduced methane emission by 10% to 34%. Addition of 6 t ha{sup {minus}1} phosphogypsum in combination with urea reduced emission by 74% as opposed to plots applied with urea alone. It is also from the results of such measurements that abatement strategies are based as regards to modifying treatments such as water management, fertilization, and choice of rice variety. It is not easy to identify and recommend mitigation strategies that will fit a particular cropping system. However, the identified mitigation options provide focus for the abatement of methane emission from ricefields.

  14. Global health benefits of mitigating ozone pollution with methane emission controls

    Science.gov (United States)

    West, J. Jason; Fiore, Arlene M.; Horowitz, Larry W.; Mauzerall, Denise L.

    2006-03-01

    Methane (CH4) contributes to the growing global background concentration of tropospheric ozone (O3), an air pollutant associated with premature mortality. Methane and ozone are also important greenhouse gases. Reducing methane emissions therefore decreases surface ozone everywhere while slowing climate warming, but although methane mitigation has been considered to address climate change, it has not for air quality. Here we show that global decreases in surface ozone concentrations, due to methane mitigation, result in substantial and widespread decreases in premature human mortality. Reducing global anthropogenic methane emissions by 20% beginning in 2010 would decrease the average daily maximum 8-h surface ozone by 1 part per billion by volume globally. By using epidemiologic ozone-mortality relationships, this ozone reduction is estimated to prevent 30,000 premature all-cause mortalities globally in 2030, and 370,000 between 2010 and 2030. If only cardiovascular and respiratory mortalities are considered, 17,000 global mortalities can be avoided in 2030. The marginal cost-effectiveness of this 20% methane reduction is estimated to be 420,000 per avoided mortality. If avoided mortalities are valued at 1 million each, the benefit is 240 per tonne of CH4 (12 per tonne of CO2 equivalent), which exceeds the marginal cost of the methane reduction. These estimated air pollution ancillary benefits of climate-motivated methane emission reductions are comparable with those estimated previously for CO2. Methane mitigation offers a unique opportunity to improve air quality globally and can be a cost-effective component of international ozone management, bringing multiple benefits for air quality, public health, agriculture, climate, and energy. human health | mortality | tropospheric ozone | air quality

  15. Oxidative mitigation of aquatic methane emissions in large Amazonian rivers.

    Science.gov (United States)

    Sawakuchi, Henrique O; Bastviken, David; Sawakuchi, André O; Ward, Nicholas D; Borges, Clovis D; Tsai, Siu M; Richey, Jeffrey E; Ballester, Maria Victoria R; Krusche, Alex V

    2016-03-01

    The flux of methane (CH4 ) from inland waters to the atmosphere has a profound impact on global atmospheric greenhouse gas (GHG) levels, and yet, strikingly little is known about the dynamics controlling sources and sinks of CH4 in the aquatic setting. Here, we examine the cycling and flux of CH4 in six large rivers in the Amazon basin, including the Amazon River. Based on stable isotopic mass balances of CH4 , inputs and outputs to the water column were estimated. We determined that ecosystem methane oxidation (MOX) reduced the diffusive flux of CH4 by approximately 28-96% and varied depending on hydrologic regime and general geochemical characteristics of tributaries of the Amazon River. For example, the relative amount of MOX was maximal during high water in black and white water rivers and minimal in clear water rivers during low water. The abundance of genetic markers for methane-oxidizing bacteria (pmoA) was positively correlated with enhanced signals of oxidation, providing independent support for the detected MOX patterns. The results indicate that MOX in large Amazonian rivers can consume from 0.45 to 2.07 Tg CH4 yr(-1) , representing up to 7% of the estimated global soil sink. Nevertheless, climate change and changes in hydrology, for example, due to construction of dams, can alter this balance, influencing CH4 emissions to atmosphere.

  16. Which role for methane emissions reduction in climate change mitigation policies; Quel role pour les reductions d'emission de methane dans la lutte contre le changement climatique?

    Energy Technology Data Exchange (ETDEWEB)

    Boucher, O. [Met Office-Hadley Centre (United Kingdom)

    2010-02-15

    Various arguments have been put forward to justify a rapid action to mitigate climate change through reductions in methane emissions. As part of a multi-gas emission reduction approach this requires defining an equivalence between methane and carbon dioxide. In this article, we discuss the physical and economical basis for a quantitative estimate of such an equivalence. Although this equivalence depends on a parameter which involves a value judgement on the most appropriate timescale for climate change, we show that it is difficult to justify a methane weight that is much different from the 100-year global warming potential that is currently used in the framework of the Kyoto protocol. (author)

  17. Towards the identification of methanogenic archaeal groups as targets of methane mitigation in livestock animals.

    Directory of Open Access Journals (Sweden)

    Benoit eSt-Pierre

    2015-07-01

    Full Text Available In herbivores, enteric methane is a by-product from the digestion of plant biomass by mutualistic gastrointestinal tract (GIT microbial communities. Methane is a potent greenhouse gas that is not assimilated by the host and is released into the environment where it contributes to climate change. Since enteric methane is exclusively produced by methanogenic archaea, the investigation of mutualistic methanogen communities in the GIT of herbivores has been the subject of ongoing research by a number of research groups. In an effort to uncover trends that would facilitate the development of efficient methane mitigation strategies for livestock species, we have in this review summarized and compared currently available results from published studies on this subject. We also offer our perspectives on the importance of pursuing current research efforts on the sequencing of gut methanogen genomes, as well as investigating their cellular physiology and interactions with other GIT microorganisms.

  18. Field-scale operation of methane biofiltration systems to mitigate point source methane emissions

    Energy Technology Data Exchange (ETDEWEB)

    Hettiarachchi, Vijayamala C. [Centre for Environmental Engineering Research and Education (CEERE), Schulich School of Engineering, University of Calgary, Calgary, AB, T2N 1N4 (Canada); Hettiaratchi, Patrick J., E-mail: jhettiar@ucalgary.ca [Centre for Environmental Engineering Research and Education (CEERE), Schulich School of Engineering, University of Calgary, Calgary, AB, T2N 1N4 (Canada); Mehrotra, Anil K. [Centre for Environmental Engineering Research and Education (CEERE), Schulich School of Engineering, University of Calgary, Calgary, AB, T2N 1N4 (Canada); Kumar, Sunil, E-mail: sunil_neeri@yahoo.co.in [Centre for Environmental Engineering Research and Education (CEERE), Schulich School of Engineering, University of Calgary, Calgary, AB, T2N 1N4 (Canada)

    2011-06-15

    Methane biofiltration (MBF) is a novel low-cost technique for reducing low volume point source emissions of methane (CH{sub 4}). MBF uses a granular medium, such as soil or compost, to support the growth of methanotrophic bacteria responsible for converting CH{sub 4} to carbon dioxide (CO{sub 2}) and water (H{sub 2}O). A field research program was undertaken to evaluate the potential to treat low volume point source engineered CH{sub 4} emissions using an MBF at a natural gas monitoring station. A new comprehensive three-dimensional numerical model was developed incorporating advection-diffusive flow of gas, biological reactions and heat and moisture flow. The one-dimensional version of this model was used as a guiding tool for designing and operating the MBF. The long-term monitoring results of the field MBF are also presented. The field MBF operated with no control of precipitation, evaporation, and temperature, provided more than 80% of CH{sub 4} oxidation throughout spring, summer, and fall seasons. The numerical model was able to predict the CH{sub 4} oxidation behavior of the field MBF with high accuracy. The numerical model simulations are presented for estimating CH{sub 4} oxidation efficiencies under various operating conditions, including different filter bed depths and CH{sub 4} flux rates. The field observations as well as numerical model simulations indicated that the long-term performance of MBFs is strongly dependent on environmental factors, such as ambient temperature and precipitation. - Highlights: > One-dimensional version of the model was used as a guiding tool for designing and operating the MBF. > Mathematical model predicted CH{sub 4} oxidation behaviors of the field MBF with high accuracy i.e. (> 80 %). > Performance of MBF is dependent on ambient temperature and precipitation. - The developed numerical model simulations and field observations for estimating CH{sub 4} oxidation efficiencies under various operating conditions indicate that

  19. On the potential for alternative greenhouse gas equivalence metrics to influence sectoral mitigation patterns

    Science.gov (United States)

    Brennan, Mark E.; Zaitchik, Benjamin F.

    2013-03-01

    Equivalence metrics used to quantify the relative climate impacts of different atmospheric forcers serve an essential function in policy and economic discussions about global climate change. The 100-year global warming potential (GWP-100), the most established greenhouse gas (GHG) equivalence metric, is used within the Kyoto Protocol, and in most emissions inventory, trading and offset mechanisms, to assign the mitigation value of non-carbon dioxide greenhouse gases relative to carbon dioxide. In recent literature the GWP-100 and alternative metrics have been used to compare various anthropogenic climate forcers with respect to a wide range of environmental and economic goals. Building on this work, we examine how 16 different static and time-varying CO2-equivalence schemes might influence GHG mitigation across sectors and gases in a perfect and fluid global mitigation regime. This mitigation regime is guided by achieving a global mean radiative forcing (RF) of 5.7 Wm-2 in 2100 from 1765 levels through a mitigation policy of prescribed emissions reductions in each decade. It was found that static metrics defined on 20- instead of 100-year time horizons favor mitigation strategies that maximize the abatement of short-lived gases (e.g. methane), on average resulting in an RF from methane in 2100 of 0.5 Wm-2 instead of 1.1 Wm-2 from 100-year metrics. Similarly, metrics that consider integrated rather than end-point climate impacts imply mitigation strategies that maximize mitigation of shorter-lived GHGs, resulting in higher abatement of agriculture and waste emissions. Comparing extreme scenarios, these mitigation shifts across gases and sectors result in a nearly 30% difference in the representation of methane in global cumulative emissions reductions. This shift across gases and sectors to mitigate shorter-lived GHGs, in lieu of longer-lived GHGs like carbon dioxide, has implications for the long-term warming commitment due to 21st century emissions.

  20. Residual feed intake and breeding approaches for enteric methane mitigation

    DEFF Research Database (Denmark)

    Berry, Donagh P; Lassen, Jan; de Hass, Y

    2015-01-01

    , the genetic variation in feed intake independent of animal performance is expectedly less than other performance traits. Nonetheless, exploitable genetic variation does exist and, if properly utilized, could augment further gains in feed efficiency. Genetic parameters for enteric methane (CH4) emissions...... in cattle are rare. No estimate of the genetic variation in enteric CH4 emissions independent of animal performance exists; it is the parameters for this trait that depict the scope for genetic improvement. The approach to the inclusion of feed intake or CH4 emissions in cattle breeding goals is not clear...... no explicit inclusion of environmental load (and in most instances, even feed efficiency) in these goals. Heritability of feed intake-related traits in cattle is moderate to high, implying that relatively high accuracy of selection can be achieved with relatively low information content per animal; however...

  1. Residual feed intake and breeding approaches for enteric methane mitigation

    DEFF Research Database (Denmark)

    Berry, Donagh P; Lassen, Jan; de Hass, Y

    2015-01-01

    no explicit inclusion of environmental load (and in most instances, even feed efficiency) in these goals. Heritability of feed intake-related traits in cattle is moderate to high, implying that relatively high accuracy of selection can be achieved with relatively low information content per animal; however......, the genetic variation in feed intake independent of animal performance is expectedly less than other performance traits. Nonetheless, exploitable genetic variation does exist and, if properly utilized, could augment further gains in feed efficiency. Genetic parameters for enteric methane (CH4) emissions...... in cattle are rare. No estimate of the genetic variation in enteric CH4 emissions independent of animal performance exists; it is the parameters for this trait that depict the scope for genetic improvement. The approach to the inclusion of feed intake or CH4 emissions in cattle breeding goals is not clear...

  2. Recent advances in measurement and dietary mitigation of enteric methane emissions in ruminants

    Directory of Open Access Journals (Sweden)

    Amlan Kumar Patra

    2016-05-01

    Full Text Available Methane (CH4 emission, which is mainly produced during normal fermentation of feeds by the rumen microorganisms, represents a major contributor to the greenhouse gas (GHG emissions. Several enteric CH4 mitigation technologies have been explored recently. A number of new techniques have also been developed and existing techniques have been improved in order to evaluate CH4 mitigation technologies and prepare an inventory of GHG emissions precisely. The aim of this review is to discuss different CH4 measuring and mitigation technologies, which have been recently developed. Respiration chamber technique is still considered as a gold standard technique due to its greater precision and reproducibility in CH4 measurements. With the adoption of recent recommendations for improving the technique, the SF6 method can be used with a high level of precision similar to the chamber technique. Short-term measurement techniques of CH4 measurements generally invite considerable within- and between animal variations. Among the short-term measuring techniques, Greenfeed and methane hood systems are likely more suitable for evaluation of CH4 mitigation studies, if measurements could be obtained at different times of the day relative to the diurnal cycle of the CH4 production. Carbon dioxide and CH4 ratio, sniffer and other short-term breath analysis techniques are more suitable for on farm screening of large number of animals to generate the data of low CH4 producing animals for genetic selection purposes. Different indirect measuring techniques are also investigated in recent years. Several new dietary CH4 mitigation technologies have been explored, but only a few of them are practical and cost-effective. Future research should be directed towards both the medium- and long-term mitigation strategies, which could be utilized on farms to accomplish substantial reductions of CH4 emissions and to profitably reduce carbon footprint of livestock production systems. This

  3. Mitigation of methane emission from an old unlined landfill in Klintholm, Denmark using a passive biocover system

    Energy Technology Data Exchange (ETDEWEB)

    Scheutz, Charlotte; Pedersen, Rasmus Broe [Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark); Petersen, Per Haugsted [Ramboll Denmark A/S, DK-5100 Odense C (Denmark); Jørgensen, Jørgen Henrik Bjerre [Klintholm I/S, DK-5874 Hasselager (Denmark); Ucendo, Inmaculada Maria Buendia; Mønster, Jacob G. [Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark); Samuelsson, Jerker [FluxSense AB/Chalmers University of Technology, SE-412 96 Göteborg (Sweden); Kjeldsen, Peter, E-mail: pekj@env.dtu.dk [Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark)

    2014-07-15

    Highlights: • An innovative biocover system was constructed on a landfill cell to mitigate the methane emission. • The biocover system had a mitigation efficiently of typically 80%. • The system also worked efficiently at ambient temperatures below freezing. • A whole landfill emission measurement tool was required to document the biocover system efficiency. - Abstract: Methane generated at landfills contributes to global warming and can be mitigated by biocover systems relying on microbial methane oxidation. As part of a closure plan for an old unlined landfill without any gas management measures, an innovative biocover system was established. The system was designed based on a conceptual model of the gas emission patterns established through an initial baseline study. The study included construction of gas collection trenches along the slopes of the landfill where the majority of the methane emissions occurred. Local compost materials were tested as to their usefulness as bioactive methane oxidizing material and a suitable compost mixture was selected. Whole site methane emission quantifications based on combined tracer release and downwind measurements in combination with several local experimental activities (gas composition within biocover layers, flux chamber based emission measurements and logging of compost temperatures) proved that the biocover system had an average mitigation efficiency of approximately 80%. The study showed that the system also had a high efficiency during winter periods with temperatures below freezing. An economic analysis indicated that the mitigation costs of the biocover system were competitive to other existing greenhouse gas mitigation options.

  4. Mitigation of methane emissions from constructed farm wetlands.

    Science.gov (United States)

    Pangala, Sunitha R; Reay, David S; Heal, Kate V

    2010-01-01

    Constructed wetlands are increasingly used for water pollution treatment but may also be sources of the greenhouse gas CH(4). The effect of addition of two potential inhibitors of methanogenesis - iron ochre and gypsum - on net CH(4) emissions was investigated in a constructed wetland treating farm runoff in Scotland, UK. CH(4) fluxes from three 15-m(2) wetland plots were measured between January and July 2008 in large static chambers incorporating a tunable diode laser, with application of 5tonha(-1) ochre and gypsum in May. CH(4) fluxes were also measured from control and ochre- and gypsum-treated wetland sediment cores incubated at constant and varying temperature in the laboratory. Ochre addition suppressed CH(4) emissions by 64+/-13% in the field plot and >90% in laboratory incubations compared to controls. Gypsum application of 5tonha(-1) in the field and laboratory experiments had no effect on CH(4) emissions, but application of 10tonha(-1) to a sediment core reduced CH(4) emissions by 28%. Suppression of CH(4) emissions by ochre application to sediment cores also increased with temperature; the reduction relative to the control increased from 50% at 17.5 degrees C to >90% at 27.5 degrees C. No significant changes in N removal or pH and potentially-toxic metal content of sediments as the result of inhibitor application were detected in the wetland during the study.

  5. Mitigation of methane emission from an old unlined landfill in Klintholm, Denmark using a passive biocover system

    DEFF Research Database (Denmark)

    Scheutz, Charlotte; Pedersen, Rasmus Broen; Petersen, Per Haugsted

    2014-01-01

    as to their usefulness as bioactive methane oxidizing material and a suitable compost mixture was selected. Whole site methane emission quantifications based on combined tracer release and downwind measurements in combination with several local experimental activities (gas composition within biocover layers, flux...... chamber based emission measurements and logging of compost temperatures) proved that the biocover system had an average mitigation efficiency of approximately 80%. The study showed that the system also had a high efficiency during winter periods with temperatures below freezing. An economic analysis...... indicated that the mitigation costs of the biocover system were competitive to other existing greenhouse gas mitigation options....

  6. Mitigation of methane emissions from rice fields: Possible adverse effects of incorporated rice straw

    Science.gov (United States)

    Sass, R. L.; Fisher, F. M.; Harcombe, P. A.; Turner, F. T.

    1991-09-01

    Increased world demand for rice production may lead to an increase in methane emission to the atmosphere and future global warming. One suggested way to reduce methane emission is to discourage the practice of incorporating previous crop residue prior to planting rice, since the residue may enhance methane emission from flooded rice fields. This concept is supported by data from a 2-year study of flooded rice fields on two different soil types in Texas. In 1990, rice stubble from 1989 was incorporated into both soils. Seasonal methane emission from a Lake Charles clay field increased from 15.9 g m-2 in 1989 to 31.0 g m-2 in 1990. In the Beaumont clay field, seasonal methane emission increased from 4.5 to 11.4 g m-2. While methane emission increased between 1989 and 1990, grain yield dropped by 2100 and 840 kg ha-1 in the Lake Charles and Beaumont fields, respectively. Visual inspection at harvest indicated that the 1990 rice yield decrease resulted from grain abortion, presumably caused by the rice cultivar's sensitivity to soil anaerobiosis. The calculated amount of organic carbon not translocated to grain was comparable to the estimated amount of organic carbon required for the increased methane emission. We hypothesize that labile carbon in straighthead susceptible rice cultivars can "leak" from roots damaged by excessively anaerobic soil and be metabolized to its equivalent in methane. These data suggest that minimizing incorporation of crop residue prior to planting can decrease methane emission from flooded rice and reduce the potential for yield loss, particularly with some cultivars and in soils with low rates of seepage and percolation.

  7. Potential for biohydrogen and methane production from olive pulp

    DEFF Research Database (Denmark)

    Gavala, Hariklia N.; Skiadas, Ioannis V.; Ahring, Birgitte Kiær;

    2005-01-01

    The present study investigates the potential for thermophilic biohydrogen and methane production from olive pulp, which is the semi-solid residue coming from the two-phase processing of olives. It focussed on: a) production of methane from the raw olive pulp, b) anaerobic bio-production of hydrogen...... and hydrogen-effluent was as high as 19 mmole CH4 per g TS. This suggests that olive pulp is an ideal substrate for methane production and it shows that biohydrogen production can be very efficiently coupled with a subsequent step for methane production....

  8. Microbial fuel cell as mitigation strategy for methane emissions from paddy field

    Science.gov (United States)

    Rizzo, Anacleto; Boano, Fulvio; Revelli, Roberto; Ridolfi, Luca

    2013-04-01

    minimum, daily maximum and total over the whole growing season, respectively, confirming the potential validity of MFC as a novel CH4 mitigation strategy. Moreover, it is shown that transport processes limit the mitigation of CH4 emissions at high current density. Finally, in order to maximize the reduction of CH4 emissions, simulation results suggest to place the anode in the middle portion of the superficial layer.

  9. Potential GHG mitigation options for agriculture in China

    Energy Technology Data Exchange (ETDEWEB)

    Erda, Lin; Yue, Li; Hongmin, Dong [Agrometeorology Institute, Beijing (China)

    1996-12-31

    Agriculture contributes more or less to anthropogenic emissions of carbon dioxide (CO{sub 2}), methane (CH{sub 4}), and nitrous oxide (N{sub 2}O). China`s agriculture accounts for about 5-15% of total emissions for these gases. Land-use changes related to agriculture are not major contributors in China. Mitigation options are available that could result in significant decrease in CH{sub 4} and N{sub 2}O emissions from agricultural systems. If implemented, they are likely to increase crop and animal productivity. Implementation has the potential to decrease CH{sub 4} emissions from rice, ruminants, and animal waste by 4-40%. The key to decreasing N{sub 2}O emissions is improving the efficiency of plant utilization of fertilizer N. This could decrease N{sub 2}O emissions from agriculture by almost 20%. Using animal waste to produce CH{sub 4} for energy and digested manure for fertilizer may at some time be cost effective. Economic analyses of options proposed should show positive economic as well as environmental benefits.

  10. Contribution of condensed tannins and mimosine to the methane mitigation caused by feeding Leucaena leucocephala.

    Science.gov (United States)

    Soltan, Yosra A; Morsy, Amr S; Sallam, Sobhy M A; Lucas, Ronaldo C; Louvandini, Helder; Kreuzer, Michael; Abdalla, Adibe L

    2013-06-01

    Leucaena (Leucaena leucocephala), a leguminous shrub promising to cope with feed scarcity in the tropics, may help in mitigating ruminal methane (CH4) emission in the tropics as well. Two experiments were conducted to evaluate the effect of Leucaena and major secondary compounds of this plant in ruminants. At first, effects of Leucaena tannins and mimosine on ruminal CH4 and nutrient degradability were tested in vitro. Incubations were made with Leucaena without or with polyethylene glycol (PEG) to exclude the tannins effects, as well as with Bermuda grass (Tifton) and lucerne hays, both either untreated or supplemented with mimosine at the same concentration that has been provided by the tested Leucaena (6.52 mg/g DM). Furthermore, in an in vivo experiment a control diet (per kg DM 700 g Tifton hay) and Leucaena diets (per kg DM 350 g Tifton hay and 350 g Leucaena), either with or without 20 g PEG/d per head, were evaluated in six Santa Inês sheep following a double Latin square design. In vitro, Leucaena resulted in the lowest (p Leucaena had no effect on ruminal CH4 and TDOM. In vivo Leucaena, compared to the Tifton diet, enhanced (p Leucaena also decreased (p Leucaena to mitigate in vivo methane emission of sheep, but did not reveal which constituent of Leucaena was primarily responsible for that since no clear efficiency of either tannins or mimosine could be demonstrated.

  11. An RF interference mitigation methodology with potential applications in scheduling

    Science.gov (United States)

    Wong, Yen F.; Rash, James L.

    1991-01-01

    Software tools for interference analysis and mitigation were developed in the Communications Link Analysis and Simulation System (CLASS) environment for: communications performance evaluation; and mission planning. Potential applications are seen in analysis, evaluation, and optimization of user schedules. Tools producing required separation angles and potential interference intervals can be used as an aid to mutual interference mitigation within a scheduling system.

  12. Potential for biohydrogen and methane production from olive pulp

    Energy Technology Data Exchange (ETDEWEB)

    Gavala, H.N.; Skiadas, I.V. [Patras Univ., Patras (Greece). Dept. of Chemical Engineering, Laboratory of Biochemical Engineering and Environmental Technology]|[Denmark Technical Univ., Lyngby (Denmark). Environmental Microbiology and Biotechnology Group; Ahring, B.K. [Denmark Technical Univ., Lyngby (Denmark). Environmental Microbiology and Biotechnology Group; Lyberatos, G. [Patras Univ., Patras (Greece). Dept. of Chemical Engineering, Laboratory of Biochemical Engineering and Environmental Technology

    2004-07-01

    Biomass rich in carbohydrates is a potential source of hydrogen. Fermentative hydrogen production includes the transformation of sugars into volatile fatty acids (VFA) without a major effect on the organic content. This study examined the potential for thermophilic biohydrogen and methane production from olive pulp, the semi-solid residue resulting from the two-phase processing of olives. Formation of VFA during acidogenesis of organic matter precedes methanogenesis. Therefore, anaerobic digestion can potentially be coupled with a preliminary step for hydrogen production. This study focused on production of methane from the raw olive pulp; anaerobic bio-production of hydrogen from the olive pulp; and, subsequent anaerobic treatment of the hydrogen-effluent with production of methane. Continuous and batch experiments were performed. The methane potential of the raw olive pulp and hydrogen effluent was up to 19 mmole of methane per gram of total solids. It was concluded that olive pulp is a suitable substrate for methane production and that biohydrogen can be coupled with a subsequent step for methane production. 12 refs., 7 tabs., 2 figs.

  13. Assessment of farm soil, biochar, compost and weathered pine mulch to mitigate methane emissions.

    Science.gov (United States)

    Syed, Rashad; Saggar, Surinder; Tate, Kevin; Rehm, Bernd H A

    2016-11-01

    Previous studies have demonstrated the effective utility of volcanic pumice soil to mitigate both high and low levels of methane (CH4) emissions through the activity of both γ-proteobacterial (type I) and α-proteobacterial (type II) aerobic methanotrophs. However, the limited availability of volcanic pumice soil necessitates the assessment of other farm soils and potentially suitable, economical and widely available biofilter materials. The potential biofilter materials, viz. farm soil (isolated from a dairy farm effluent pond bank area), pine biochar, garden waste compost and weathered pine bark mulch, were inoculated with a small amount of volcanic pumice soil. Simultaneously, a similar set-up of potential biofilter materials without inoculum was studied to understand the effect of the inoculum on the ability of these materials to oxidise CH4 and their effect on methanotroph growth and activity. These materials were incubated at 25 °C with periodic feeding of CH4, and flasks were aerated with air (O2) to support methanotroph growth and activity by maintaining aerobic conditions. The efficiency of CH4 removal was monitored over 6 months. All materials supported the growth and activity of methanotrophs. However, the efficiency of CH4 removal by all the materials tested fluctuated between no or low removal (0-40 %) and high removal phases (>90 %), indicating biological disturbances rather than physico-chemical changes. Among all the treatments, CH4 removal was consistently high (>80 %) in the inoculated farm soil and inoculated biochar, and these were more resilient to changes in the methanotroph community. The CH4 removal from inoculated farm soil and inoculated biochar was further enhanced (up to 99 %) by the addition of a nutrient solution. Our results showed that (i) farm soil and biochar can be used as a biofilter material by inoculating with an active methanotroph community, (ii) an abundant population of α-proteobacterial methanotrophs is essential

  14. Potential and existing mechanisms of enteric methane production in ruminants

    Directory of Open Access Journals (Sweden)

    Junyi Qiao

    2014-10-01

    Full Text Available Enteric methane (CH4 emissions in ruminants have attracted considerable attention due to their impact on greenhouse gases and the contribution of agricultural practices to global warming. Over the last two decades, a number of approaches have been adopted to mitigate CH4 emissions. However, the mechanisms of methanogenesis have still not been fully defined. According to the genome sequences of M. ruminantium in the rumen and of M. AbM4 in the abomasum, the pathways of carbon dioxide (CO2 reduction and formate oxidation to CH4 have now been authenticated in ruminants. Furthermore, in the light of species or genera description of methanogens, the precursors of methanogenesis discovered in the rumen and research advances in related subjects, pathways of acetate dissimilation via Methanosarcina and Methanosaeta as well as metabolism of methanol to CH4 might be present in the rumen, although neither process has yet been experimentally demonstrated in the rumen. Herein the research advances in methanogenesic mechanisms including existing and potential mechanisms are reviewed in detail. In addition, further research efforts to understand the methanogenesis mechanism should focus on isolation and identification of more specific methanogens, and their genome sequences. Such increased knowledge will provide benefits in terms of improved dietary energy utilization and a reduced contribution of enteric CH4 emissions to total global greenhouse gas emissions from the ruminant production system.

  15. Quantifying, Assessing, and Mitigating Methane Emissions from Super-emitters in the Oil and Gas Supply Chain

    Science.gov (United States)

    Lyon, David Richard

    Methane emissions from the oil and gas (O&G) supply chain reduce potential climate benefits of natural gas as a replacement for other fossil fuels that emit more carbon dioxide per energy produced. O&G facilities have skewed emission rate distributions with a small fraction of sites contributing the majority of emissions. Knowledge of the identity and cause of these high emission facilities, referred to as super-emitters or fat-tail sources, is critical for reducing supply chain emissions. This dissertation addresses the quantification of super-emitter emissions, assessment of their prevalence and relationship to site characteristics, and mitigation with continuous leak detection systems. Chapter 1 summarizes the state of the knowledge of O&G methane emissions. Chapter 2 constructs a spatially-resolved emission inventory to estimate total and O&G methane emissions in the Barnett Shale as part of a coordinated research campaign using multiple top-down and bottom-up methods to quantify emissions. The emission inventory accounts for super-emitters with two-phase Monte Carlo simulations that combine site measurements collected with two approaches: unbiased sampling and targeted sampling of super-emitters. More comprehensive activity data and the inclusion of super-emitters, which account for 19% of O&G emissions, produces a emission inventory that is not statistically different than top-down regional emission estimates. Chapter 3 describes a helicopter-based survey of over 8,000 well pads in seven basins with infrared optical gas imaging to assess high emission sources. Four percent of sites are observed to have high emissions with over 90% of observed sources from tanks. The occurrence of high emissions is weakly correlated to site parameters and the best statistical model explains only 14% of variance, which demonstrates that the occurrence of super-emitters is primarily stochastic. Chapter 4 presents a Gaussian dispersion model for optimizing the placement of

  16. The Potential Role of Seaweeds in the Natural Manipulation of Rumen Fermentation and Methane Production

    Science.gov (United States)

    Maia, Margarida R. G.; Fonseca, António J. M.; Oliveira, Hugo M.; Mendonça, Carla; Cabrita, Ana R. J.

    2016-08-01

    This study is the first to evaluate the effects of five seaweeds (Ulva sp., Laminaria ochroleuca, Saccharina latissima, Gigartina sp., and Gracilaria vermiculophylla) on gas and methane production and ruminal fermentation parameters when incubated in vitro with two substrates (meadow hay and corn silage) for 24 h. Seaweeds led to lower gas production, with Gigartina sp. presenting the lowest value. When incubated with meadow hay, Ulva sp., Gigartina sp. and G. vermiculophylla decreased methane production, but with corn silage, methane production was only decreased by G. vermiculophylla. With meadow hay, L. ochroleuca and S. latissima promoted similar methane production as the control, but with corn silage, L. ochroleuca increased it. With the exception of S. latissima, all seaweeds promoted similar levels of total volatile fatty acid production. The highest proportion of acetic acid was produced with Ulva sp., G. vermiculophylla, and S. latissima; the highest proportion of butyric acid with the control and L. ochroleuca; and the highest proportion of iso-valeric acid with Gigartina sp. These results reveal the potential of seaweeds to mitigate ruminal methane production and the importance of the basal diet. To efficiently use seaweeds as feed ingredients with nutritional and environmental benefits, more research is required to determine the mechanisms underlying seaweed and substrate interactions.

  17. The Potential Role of Seaweeds in the Natural Manipulation of Rumen Fermentation and Methane Production

    Science.gov (United States)

    Maia, Margarida R. G.; Fonseca, António J. M.; Oliveira, Hugo M.; Mendonça, Carla; Cabrita, Ana R. J.

    2016-01-01

    This study is the first to evaluate the effects of five seaweeds (Ulva sp., Laminaria ochroleuca, Saccharina latissima, Gigartina sp., and Gracilaria vermiculophylla) on gas and methane production and ruminal fermentation parameters when incubated in vitro with two substrates (meadow hay and corn silage) for 24 h. Seaweeds led to lower gas production, with Gigartina sp. presenting the lowest value. When incubated with meadow hay, Ulva sp., Gigartina sp. and G. vermiculophylla decreased methane production, but with corn silage, methane production was only decreased by G. vermiculophylla. With meadow hay, L. ochroleuca and S. latissima promoted similar methane production as the control, but with corn silage, L. ochroleuca increased it. With the exception of S. latissima, all seaweeds promoted similar levels of total volatile fatty acid production. The highest proportion of acetic acid was produced with Ulva sp., G. vermiculophylla, and S. latissima; the highest proportion of butyric acid with the control and L. ochroleuca; and the highest proportion of iso-valeric acid with Gigartina sp. These results reveal the potential of seaweeds to mitigate ruminal methane production and the importance of the basal diet. To efficiently use seaweeds as feed ingredients with nutritional and environmental benefits, more research is required to determine the mechanisms underlying seaweed and substrate interactions. PMID:27572486

  18. The Potential Role of Seaweeds in the Natural Manipulation of Rumen Fermentation and Methane Production.

    Science.gov (United States)

    Maia, Margarida R G; Fonseca, António J M; Oliveira, Hugo M; Mendonça, Carla; Cabrita, Ana R J

    2016-08-30

    This study is the first to evaluate the effects of five seaweeds (Ulva sp., Laminaria ochroleuca, Saccharina latissima, Gigartina sp., and Gracilaria vermiculophylla) on gas and methane production and ruminal fermentation parameters when incubated in vitro with two substrates (meadow hay and corn silage) for 24 h. Seaweeds led to lower gas production, with Gigartina sp. presenting the lowest value. When incubated with meadow hay, Ulva sp., Gigartina sp. and G. vermiculophylla decreased methane production, but with corn silage, methane production was only decreased by G. vermiculophylla. With meadow hay, L. ochroleuca and S. latissima promoted similar methane production as the control, but with corn silage, L. ochroleuca increased it. With the exception of S. latissima, all seaweeds promoted similar levels of total volatile fatty acid production. The highest proportion of acetic acid was produced with Ulva sp., G. vermiculophylla, and S. latissima; the highest proportion of butyric acid with the control and L. ochroleuca; and the highest proportion of iso-valeric acid with Gigartina sp. These results reveal the potential of seaweeds to mitigate ruminal methane production and the importance of the basal diet. To efficiently use seaweeds as feed ingredients with nutritional and environmental benefits, more research is required to determine the mechanisms underlying seaweed and substrate interactions.

  19. Mitigation of ammonia, nitrous oxide and methane emissions from manure management chains: a meta-analysis and integrated assessment

    NARCIS (Netherlands)

    Yong, Y.; Velthof, G.L.; Oenema, O.

    2015-01-01

    Livestock manure contributes considerably to global emissions of ammonia (NH3) and greenhouse gases (GHG), especially methane (CH4) and nitrous oxide (N2O). Various measures have been developed to mitigate these emissions, but most of these focus on one specific gas and/or emission source. Here, we

  20. Mitigation of ammonia, nitrous oxide and methane emissions from manure management chains: a meta-analysis and integrated assessment

    NARCIS (Netherlands)

    Yong, Y.; Velthof, G.L.; Oenema, O.

    2015-01-01

    Livestock manure contributes considerably to global emissions of ammonia (NH3) and greenhouse gases (GHG), especially methane (CH4) and nitrous oxide (N2O). Various measures have been developed to mitigate these emissions, but most of these focus on one specific gas and/or emission source. Here, we

  1. Chemical composition and methane potential of commercial food wastes.

    Science.gov (United States)

    Lopez, Victoria M; De la Cruz, Florentino B; Barlaz, Morton A

    2016-10-01

    There is increasing interest in anaerobic digestion in the U.S. However, there is little information on the characterization of commercial food waste sources as well as the effect of waste particle size on methane yield. The objective of this research was to characterize four commercial food waste sources: (1) university dining hall waste, (2) waste resulting from prepared foods and leftover produce at a grocery store, (3) food waste from a hotel and convention center, and (4) food preparation waste from a restaurant. Each sample was tested in triplicate 8L batch anaerobic digesters after shredding and after shredding plus grinding. Average methane yields for the university dining, grocery store, hotel, and restaurant wastes were 363, 427, 492, and 403mL/dry g, respectively. Starch exhibited the most complete consumption and particle size did not significantly affect methane yields for any of the tested substrates. Lipids represented 59-70% of the methane potential of the fresh substrates.

  2. Global Air Quality and Health Co-benefits of Mitigating Near-term Climate Change Through Methane and Black Carbon Emission Controls

    Science.gov (United States)

    Anenberg, Susan C.; Schwartz, Joel; Shindell, Drew Todd; Amann, Markus; Faluvegi, Gregory S.; Klimont, Zbigniew; Janssens-Maenhout, Greet; Pozzoli, Luca; Dingenen, Rita Van; Vignati, Elisabetta; Emberson, Lisa; Muller, Nicholas Z.; West, J. Jason; Williams, Martin; Demkine, Volodymyr; Hicks, W. Kevin; Kuylenstierna, Johan; Raes, Frank; Ramanathan, Veerabhadran

    2012-01-01

    Tropospheric ozone and black carbon (BC), a component of fine particulate matter (PM air quality and health benefits of 14 specific emission control measures targeting BC and methane, an ozone precursor, that were selected because of their potential to reduce the rate of climate change over the next 20-40 years. Methods: We simulated the impacts of mitigation measures on outdoor concentrations of PM2.5 and ozone using two composition-climate models, and calculated associated changes in premature PM2.5- and ozone-related deaths using epidemiologically derived concentration-response functions. Results: We estimated that, for PM2.5 and ozone, respectively, fully implementing these measures could reduce global population-weighted average surface concentrations by 23-34% and 7-17% and avoid 0.6-4.4 and 0.04-0.52 million annual premature deaths globally in 2030. More than 80% of the health benefits are estimated to occur in Asia. We estimated that BC mitigation measures would achieve approximately 98% of the deaths that would be avoided if all BC and methane mitigation measures were implemented, due to reduced BC and associated reductions of nonmethane ozone precursor and organic carbon emissions as well as stronger mortality relationships for PM2.5 relative to ozone. Although subject to large uncertainty, these estimates and conclusions are not strongly dependent on assumptions for the concentration-response function. Conclusions: In addition to climate benefits, our findings indicate that the methane and BC emission control measures would have substantial co-benefits for air quality and public health worldwide, potentially reversing trends of increasing air pollution concentrations and mortality in Africa and South, West, and Central Asia. These projected benefits are independent of carbon dioxide mitigation measures. Benefits of BC measures are underestimated because we did not account for benefits from reduced indoor exposures and because outdoor exposure estimates

  3. Anaerobic methane oxidation coupled to nitrite reduction can be a potential methane sink in coastal environments.

    Science.gov (United States)

    Shen, Li-Dong; Hu, Bao-Lan; Liu, Shuai; Chai, Xiao-Ping; He, Zhan-Fei; Ren, Hong-Xing; Liu, Yan; Geng, Sha; Wang, Wei; Tang, Jing-Liang; Wang, Yi-Ming; Lou, Li-Ping; Xu, Xiang-Yang; Zheng, Ping

    2016-08-01

    In the current study, we investigated nitrite-dependent anaerobic methane oxidation (N-DAMO) as a potential methane sink in the Hangzhou Bay and the adjacent Zhoushan sea area. The potential activity of the N-DAMO process was primarily observed in Hangzhou Bay by means of (13)C-labeling experiments, whereas very low or no potential N-DAMO activity could be detected in the Zhoushan sea area. The measured potential N-DAMO rates ranged from 0.2 to 1.3 nmol (13)CO2 g(-1) (dry sediment) day(-1), and the N-DAMO potentially contributed 2.0-9.4 % to the total microbial methane oxidation in the examined sediments. This indicated that the N-DAMO process may be an alternative pathway in the coastal methane cycle. Phylogenetic analyses confirmed the presence of Candidatus Methylomirabilis oxyfera-like bacteria in all the examined sediments, while the group A members (the dominant bacteria responsible for N-DAMO) were found mainly in Hangzhou Bay. Quantitative PCR showed that the 16S rRNA gene abundance of Candidatus M. oxyfera-like bacteria varied from 5.4 × 10(6) to 5.0 × 10(7) copies g(-1) (dry sediment), with a higher abundance observed in Hangzhou Bay. In addition, the overlying water NO3 (-) concentration and salinity were identified as the most important factors influencing the abundance and potential activity of Candidatus M. oxyfera-like bacteria in the examined sediments. This study showed the evidence of N-DAMO in coastal environments and indicated the importance of N-DAMO as a potential methane sink in coastal environments.

  4. Influence of headspace pressure on methane production in Biochemical Methane Potential (BMP) tests.

    Science.gov (United States)

    Valero, David; Montes, Jesús A; Rico, José Luis; Rico, Carlos

    2016-02-01

    The biochemical methane potential test is the most commonly applied method to determine methane production from organic wastes. One of the parameters measured is the volume of biogas produced which can be determined manometrically by keeping the volume constant and measuring increases in pressure. In the present study, the effect of pressure accumulation in the headspace of the reactors has been studied. Triplicate batch trials employing cocoa shell, waste coffee grounds and dairy manure as substrates have been performed under two headspace pressure conditions. The results obtained in the study showed that headspace overpressures higher than 600mbar affected methane production for waste coffee grounds. On the contrary, headspace overpressures within a range of 600-1000mbar did not affect methane production for cocoa shell and dairy manure. With the analyses performed in the present work it has not been possible to determine the reasons for the lower methane yield value obtained for the waste coffee grounds under high headspace pressures. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Potential application of biocover soils to landfills for mitigating toluene emission.

    Science.gov (United States)

    Su, Yao; Pei, Junshen; Tian, Baohu; Fan, Fengxi; Tang, Mengling; Li, Wei; He, Ruo

    2015-12-15

    Biocover soils have been demonstrated to be a good alternative cover material to mitigate CH4 emission from landfills. To evaluate the potential of biocover soil in mitigating emissions of non-methane volatile organic compounds (NMVOCs) from landfills, simulated cover soil columns with the influx of toluene (chosen as typical of NMVOCs) concentrations of 102-1336 mg m(-3) in the presence or absence of the major landfill gas components (i.e., CH4 and CO2) were conducted in this study. In the two experimental materials (waste biocover soils (WBS) and landfill cover soils (LCS)), higher toluene reduction was observed in WBS with respect to LCS. After the introduction of landfill gas, an increase of microbial diversity and relative abundance of toluene-degrading bacteria and methanotrophs occurred in WBS. To illustrate the role of toluene-degrading activity in mitigating toluene emissions through landfill covers, an analytical model was developed by incorporating the steady-state vapor transport with the first-order kinetics of aerobic biodegradation limited by O2 availability. This study demonstrated that biocover soils have great potential in applying to landfills for mitigating toluene emission to the atmosphere.

  6. The Potential for Methane Isotopologue Channels in GOSAT-2

    Science.gov (United States)

    Malina, Edward; Yoshida, Yukio; Matsunaga, Tsuneo; Muller, Jan-Peter

    2017-04-01

    Of the major Greenhouse Gases (GHGs) currently considered as having a major impact on atmospheric chemistry, Methane is amongst the most important (IPCC, 2014). Methane concentration in the atmosphere has been documented to be rising steadily over the past century, aside from an unexplained short period in the middle of the last decade (Heimann., 2011), leading to renewed efforts to understand global atmospheric Methane. Atmospheric Methane is primarily composed of two key isotopologues, 12CH4 and 13CH4, which have a natural abundance of about 98% and 1.1% respectively. It is a well-established fact that different sources of Methane (i.e. biogenic sources such as methanogens, or non-biogenic such as industrial hydrocarbon burning) vary in the abundance of these isotopologues (Etiope, 2009). The global identification of the ratios of these isotopologues could vastly increase knowledge of global Methane sources, and shed some light on global Methane growth. GOSAT-2 due to be launched in 2018 is a follow on from the original GOSAT mission launched in 2009. GOSAT-2 aims to continue the legacy of GOSAT by providing global measurements of Methane and Carbon Dioxide on a global basis in order to monitor GHG emissions. GOSAT-2 in the context of this study has a significant advantage over GOSAT, which is the extension of the sensitivity of band 3 to 2330nm from 2080nm where significant numbers of Methane spectral lines are located. In this study we apply the well-established Information Content (IC) analysis techniques originally proposed by Rodgers (2000) to determine the potential benefit of retrieving total column Methane isotopologue concentrations assuming bands 2 and 3 of the GOSAT-2/TANSO-FTS-2 instrument. The value of such studies has been proven on multiple occasions and can provide guidance on appropriate potential retrieval setups. Due to the fact that there has been limited research in this area, no 'a priori' state vectors or Variance Covariance Matrices (VCMs

  7. Gas Production Potential in the Landfill of Tehran by Landfill Methane Outreach Program

    Directory of Open Access Journals (Sweden)

    Pazoki

    2015-10-01

    Full Text Available Background Landfilling is the most common way of municipal solid waste (MSW disposal in Iran. Many countries have targeted landfill methane recovery among greenhouse gas mitigation strategies, since methane is the second most important greenhouse gas after carbon dioxide. Major questions remain with respect to actual methane production rates in field settings as well as the relative mass of methane that is recovered, emitted, oxidized by methanotrophic bacteria, laterally migrated, or temporarily stored within the landfill volume. Landfill gas (LFG consists of 50% - 60 vol% methane and 30% - 40 vol% carbon dioxide as well as trace amounts of numerous chemical compounds such as aromatics, chlorinated organic compounds and sulfur compounds. Landfill methane outreach program (LMOP is a voluntary assistance program which helps reduce methane emissions from landfills by encouraging the recovery and the beneficial use of LFG as an energy resource. Objectives In this study, the volume of LFG of Tehran by landfill methane outreach program (LMOP software was calculated. In addition, the relationship between the time of gas collection system operation and the volume of LFG production was evaluated. Materials and Methods The LMOP software was used. The available information and some presumptions were used to operate the software. The composition of the solid waste collected from the landfill of Tehran had specific details. A large amount of it was organic materials, which was about 67.8%. These materials have a good potential to produce gas. In addition, LMOP Colombia model uses the first-order equations in all the analytical equations. Furthermore, it is assumed that the landfill operation time is 30 years and the process is considered in two conditions; first, the gas was recovered in 2000, and second, the process started in 2015. Results The modeling results showed that for the gas recovery starting in 2000 and 2015, the power generation would be 2

  8. Measurement and mitigation of methane emissions from beef cattle in tropical grazing systems: a perspective from Australia and Brazil.

    Science.gov (United States)

    Berndt, A; Tomkins, N W

    2013-06-01

    The growing global demand for food of animal origin will be the incentive for countries such as Australia and Brazil to increase their beef production and international exports. This increased supply of beef is expected to occur primarily through on-farm productivity increases. The strategies for reducing resultant greenhouse gas (GHG) emissions should be evaluated in the context of the production system and should encompass a broader analysis, which would include the emissions of methane (CH4) and nitrous oxide (N2O) and carbon sequestration. This paper provides an insight into CH4 measurement techniques applicable to grazing environments and proposed mitigation strategies, with relevance to the production systems that are predominant in grazing systems of Australia and Brazil. Research and technology investment in both Australia and Brazil is aimed at developing measurement techniques and increasing the efficiency of cattle production by improving herd genetics, utilization of the seasonal feed-base and reducing the proportion of metabolizable energy lost as CH4. Concerted efforts in these areas can be expected to reduce the number of unproductive animals, reduce age at slaughter and inevitably reduce emission intensity (EI) from beef production systems. Improving efficiency of livestock production systems in tropical grazing systems for Australia and Brazil will be based on cultivated and existing native pastures and the use of additives and by-products from other agricultural sectors. This approach spares grain-based feed reserves typically used for human consumption, but potentially incurs a heavier EI than current intensive feeding systems. The determination of GHG emissions and the value of mitigation outcomes for entire beef production systems in the extensive grazing systems is complex and require a multidisciplinary approach. It is fortunate that governments in both Australia and Brazil are supporting ongoing research activities. Nevertheless, to achieve

  9. Solar enriched methane production: Assessment of plant potentialities and applications

    Directory of Open Access Journals (Sweden)

    Vincenzo Piemonte

    2010-04-01

    Full Text Available The crucial environmental issue due to fossil fuel use in our society and industries and more and more perceived by the communities is stimulating the development of innovative technologies with the scope of reducing GHGs and pollutants emissions, improving plants efficiency and exploiting renewable energy sources. The idea proposed in the present work links this context: a novel hybrid plant for the production of a mixture of methane and hydrogen (20%vol, called enriched-methane, from a steam reforming reactor whose heat duty is supplied by a concentrating solar power (CSP plant by means of a molten salt stream is here conceived, modelled and assessed. The enriched-methane mixture can be applied in methane internal combustion engines (ICE reducing CO, CO2, unburned emissions and improving engine efficiency. Moreover, the residual sensible heat of solar-heated molten salt stream can be used to generate medium-pressure steam and to produce electricity by a steam-turbine. Therefore, the plant proposed is co-generative, producing both hydrogen and electricity from a solar source. The behaviour of methane steam reforming reactor is simulated by means of a 2D mathematical model and the design of a cogenerative solar plant is proposed, evaluating its potentialities in terms of MWh of electricity produced and number of vehicles fed by enriched-methane. A single CSP module (surface requirement = 1.5 hectares coupled with a 4-tubes-and-shell shaped reactor is able to produce 686 tons/year of hydrogen, equivalent to 3.430 tons/year of 20%vol H2-CH4 mixture and 3.097 MWh/year of clean electricity.

  10. Genetic parameters for predicted methane production and potential for reducing enteric emissions through genomic selection.

    Science.gov (United States)

    Haas, Y de; Windig, J J; Calus, M P L; Dijkstra, J; Haan, M de; Bannink, A; Veerkamp, R F

    2011-12-01

    Mitigation of enteric methane (CH₄) emission in ruminants has become an important area of research because accumulation of CH₄ is linked to global warming. Nutritional and microbial opportunities to reduce CH₄ emissions have been extensively researched, but little is known about using natural variation to breed animals with lower CH₄ yield. Measuring CH₄ emission rates directly from animals is difficult and hinders direct selection on reduced CH₄ emission. However, improvements can be made through selection on associated traits (e.g., residual feed intake, RFI) or through selection on CH₄ predicted from feed intake and diet composition. The objective was to establish phenotypic and genetic variation in predicted CH₄ output, and to determine the potential of genetics to reduce methane emissions in dairy cattle. Experimental data were used and records on daily feed intake, weekly body weights, and weekly milk production were available from 548 heifers. Residual feed intake (MJ/d) is the difference between net energy intake and calculated net energy requirements for maintenance as a function of body weight and for fat- and protein-corrected milk production. Predicted methane emission (PME; g/d) is 6% of gross energy intake (Intergovernmental Panel on Climate Change methodology) corrected for energy content of methane (55.65 kJ/g). The estimated heritabilities for PME and RFI were 0.35 and 0.40, respectively. The positive genetic correlation between RFI and PME indicated that cows with lower RFI have lower PME (estimates ranging from 0.18 to 0.84). Hence, it is possible to decrease the methane production of a cow by selecting more-efficient cows, and the genetic variation suggests that reductions in the order of 11 to 26% in 10 yr are theoretically possible, and could be even higher in a genomic selection program. However, several uncertainties are discussed; for example, the lack of true methane measurements (and the key assumption that methane

  11. Current California Drought: Impact on Citrus Trees and Potential Mitigation

    Science.gov (United States)

    California is in another cycle of extended drought. The article reviews and discusses likely impact of the current drought on citrus growers and potential mitigation techniques. Citrus physiological responses to water stress is briefly reviewed. The direct impact of drought on citrus is reduced frui...

  12. Biogenic methane potential of marine sediments. Application of chemical thermodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Arning, E.T.; Schulz, H.M. [Helmholtz Centre Potsdam GFZ, Potsdam (Germany); Berk, W. van [Technical Univ. of Clausthal (Germany). Dept. of Hydrogeology

    2013-08-01

    Accumulations of biogenic methane-dominated gas are widespread and occur in a variety of depositional settings and rock types. However, the potential of biogenic methane remains underexplored. This is mainly due to the fact that quantitative assessments applying numerical modeling techniques for exploration purposes are generally lacking to date. Biogenic methane formation starts in relatively shallow marine sediments below the sulfate reduction zone. When sulfate is exhausted, methanogenesis via the CO{sub 2} reduction pathway is often the dominant biogenic methane formation process in marine sediments (Claypool and Kaplan, 1974). The process can be simplified by the reaction: 2CH{sub 2}O + Ca{sup 2+} + H{sub 2}O {yields} CH{sub 4} + CaCO{sub 3} + 2H{sup +}. The products of early diagenetic reactions initiate coupled equilibrium reactions that induce a new state of chemical equilibrium among minerals, pore water and gas. The driving force of the complex biogeochemical reactions in sedimentary environments during early diagenesis is the irreversible redox-conversion of organic matter. Early diagenetic formation of biogenic methane shortly after deposition ('early diagenesis') was retraced using PHREEQC computer code that is applied to calculate homogenous and heterogeneous mass-action equations in combination with one-dimensional diffusion driven transport (Parkhurst and Appelo, 1999). Our modeling approach incorporates interdependent diagenetic reactions evolving into a diffusive multi-component and multiphase system by means of thermodynamic equilibrium calculations of species distribution (Arning et al., 2011, 2012, 2013). Reaction kinetics of organic carbon conversion is integrated into the set of equilibrium reactions by defining type and amount of converted organic matter in a certain time step. It is the aim (1) to calculate quantitatively thermodynamic equilibrium conditions (composition of pore water, mineral phase and gas phase assemblage) in

  13. The Mitigative Potential of Urban Environments and Their Microclimates

    Directory of Open Access Journals (Sweden)

    Rosa Schiano-Phan

    2015-07-01

    Full Text Available Cities play a crucial role in climate change: More than 50% of the growing population lives in cities producing most of the global GDP but also 78% of greenhouse gases (GHG responsible for climate change. Moreover, due to their highly modified land-use and intensive activities, cities are at the forefront of the most rapid environmental and climatic change ever experienced by mankind. Yet, cities’ potential to mitigate both climate change and their own environment is underexploited. This paper explores ideas related to the potential of urban environments to modify their microclimates, reflecting on the overlapping potential between mitigative and adaptive actions. These actions in cities can not only tackle some of the largest contributing factors to global climate change but offer short- to medium-term benefits that could drive more immediate socioeconomic and behavioral changes. This review proposes and discusses a new preliminary definition of urban environments as microclimate modifiers—Mitigative urban Environments and Microclimates (MitEM—and calls for further research into: (a inter-connecting the full range of mitigative and adaptive initiatives already being undertaken in many cities and maximizing their input systemically; (b developing a common and holistic definition of MitEM; (c promoting its uptake at policy level and amongst the key stakeholders, based on its social and public value beyond the environmental.

  14. Potentials to mitigate climate change using biochar - the Austrian perspective

    Science.gov (United States)

    Bruckman, Viktor J.; Klinglmüller, Michaela; Liu, Jay; Uzun, Basak B.; Varol, Esin A.

    2015-04-01

    Biomass utilization is seen as one of various promising strategies to reduce additional carbon emissions. A recent project on potentials of biochar to mitigate climate change (FOREBIOM) goes even a step further towards bioenergy in combination of CCS or "BECS" and tries to assess the current potentials, from sustainable biomass availability to biochar amendment in soils, including the identification of potential disadvantages and current research needs. The current report represents an outcome of the 1st FOREBIOM Workshop held in Vienna in April, 2013 and tries to characterize the Austrian perspective of biochar for climate change mitigation. The survey shows that for a widespread utilization of biochar in climate change mitigation strategies, still a number of obstacles have to be overcome. There are concerns regarding production and application costs, contamination and health issues for both producers and customers besides a fragmentary knowledge about biochar-soil interactions specifically in terms of long-term behavior, biochar stability and the effects on nutrient cycles. However, there are a number of positive examples showing that biochar indeed has the potential to sequester large amounts of carbon while improving soil properties and subsequently leading to a secondary carbon sink via rising soil productivity. Diversification, cascadic utilization and purpose designed biochar production are key strategies overcoming initial concerns, especially regarding economic aspects. A theoretical scenario calculation showed that relatively small amounts of biomass that is currently utilized for energy can reduce the gap between Austria's current GHG emissions and the Kyoto target by about 30% if biomass residues are pyrolized and biochar subsequently used as soil amendment. However, by using a more conservative approach that is representing the aims of the underlying FOREBIOM project (assuming that 10% of the annual biomass increment from forests is used for biochar

  15. Polyhydroxyalkanoates in waste activated sludge enhances anaerobic methane production through improving biochemical methane potential instead of hydrolysis rate

    Science.gov (United States)

    Wang, Qilin; Sun, Jing; Zhang, Chang; Xie, Guo-Jun; Zhou, Xu; Qian, Jin; Yang, Guojing; Zeng, Guangming; Liu, Yiqi; Wang, Dongbo

    2016-01-01

    Anaerobic sludge digestion is the main technology for sludge reduction and stabilization prior to sludge disposal. Nevertheless, methane production from anaerobic digestion of waste activated sludge (WAS) is often restricted by the poor biochemical methane potential and slow hydrolysis rate of WAS. This work systematically investigated the effect of PHA levels of WAS on anaerobic methane production, using both experimental and mathematical modeling approaches. Biochemical methane potential tests showed that methane production increased with increased PHA levels in WAS. Model-based analysis suggested that the PHA-based method enhanced methane production by improving biochemical methane potential of WAS, with the highest enhancement being around 40% (from 192 to 274 L CH4/kg VS added; VS: volatile solid) when the PHA levels increased from 21 to 143 mg/g VS. In contrast, the hydrolysis rate (approximately 0.10 d‑1) was not significantly affected by the PHA levels. Economic analysis suggested that the PHA-based method could save $1.2/PE/y (PE: population equivalent) in a typical wastewater treatment plant (WWTP). The PHA-based method can be easily integrated into the current WWTP to enhance methane production, thereby providing a strong support to the on-going paradigm shift in wastewater management from pollutant removal to resource recovery.

  16. Greenhouse gas mitigation potentials in the livestock sector

    Science.gov (United States)

    Herrero, Mario; Henderson, Benjamin; Havlík, Petr; Thornton, Philip K.; Conant, Richard T.; Smith, Pete; Wirsenius, Stefan; Hristov, Alexander N.; Gerber, Pierre; Gill, Margaret; Butterbach-Bahl, Klaus; Valin, Hugo; Garnett, Tara; Stehfest, Elke

    2016-05-01

    The livestock sector supports about 1.3 billion producers and retailers, and contributes 40-50% of agricultural GDP. We estimated that between 1995 and 2005, the livestock sector was responsible for greenhouse gas emissions of 5.6-7.5 GtCO2e yr-1. Livestock accounts for up to half of the technical mitigation potential of the agriculture, forestry and land-use sectors, through management options that sustainably intensify livestock production, promote carbon sequestration in rangelands and reduce emissions from manures, and through reductions in the demand for livestock products. The economic potential of these management alternatives is less than 10% of what is technically possible because of adoption constraints, costs and numerous trade-offs. The mitigation potential of reductions in livestock product consumption is large, but their economic potential is unknown at present. More research and investment are needed to increase the affordability and adoption of mitigation practices, to moderate consumption of livestock products where appropriate, and to avoid negative impacts on livelihoods, economic activities and the environment.

  17. Effect of industrial by-products containing electron acceptors on mitigating methane emission during rice cultivation.

    Science.gov (United States)

    Ali, Muhammad Aslam; Lee, Chang Hoon; Kim, Sang Yoon; Kim, Pil Joo

    2009-10-01

    Three industrial by-products (fly ash, phosphogypsum and blast furnace slag), were evaluated for their potential re-use as soil amendments to reduce methane (CH(4)) emission resulting from rice cultivation. In laboratory incubations, CH(4) production rates from anoxic soil slurries were significantly reduced at amendment levels of 0.5%, 1%, 2% and 5% (wt wt(-1)), while observed CO(2) production rates were enhanced. The level of suppression in methane production was the highest for phosphogypsum, followed by blast slag and then fly ash. In the greenhouse experiment, CH(4) emission rates from the rice planted potted soils significantly decreased with the increasing levels (2-20 Mg ha(-1)) of the selected amendments applied, while rice yield simultaneously increased compared to the control treatment. At 10 Mg ha(-1) application level of the amendments, total seasonal CH(4) emissions were reduced by 20%, 27% and 25%, while rice grain yields were increased by 17%, 15% and 23% over the control with fly ash, phosphogypsum, and blast slag amendments, respectively. The suppression of CH(4) production rates as well as total seasonal CH(4) flux could be due to the increased concentrations of active iron, free iron, manganese oxides, and sulfate in the amended soil, which acted as electron acceptors and controlled methanogens' activity by limiting substrates availability. Among the amendments, blast furnace slag and fly ash contributed mainly to improve the soil nutrients balance and increased the soil pH level towards neutral point, but soil acidity was developed with phosphogypsum application. Conclusively, blast slag among the selected amendments would be a suitable soil amendment for reducing CH(4) emissions as well as sustaining rice productivity.

  18. Constraining the abundance of high emitters is critical to mitigating the effect of abandoned oil and gas wells on methane emissions

    Science.gov (United States)

    Townsend-Small, A.; Ferrara, T.; Fries, A. E.

    2016-12-01

    Recent studies have suggested that methane inventories may underrepresent emissions from the oil and gas supply chain, and this has led to an effort by several groups to assess whether abandoned wells are a significant source. Our work has shown that unplugged wells are a larger source than plugged wells, and that a small percentage of unplugged wells likely make up the majority of emissions. Preliminary work also suggests that the oldest oil and gas producing region, the Appalachian Basin, has the largest emitters. However, many of these wells are over 100 years old and state databases lack accurate plugging and location data. Our current work is focused on determining the proportion of high emitters among abandoned wells in the Appalachian basin of Ohio. We are also making component-level measurements of conventional oil and gas wells on federal land for comparison. Our methods include analysis of gas composition to identify the relative contributions of biogenic and thermogenic methane to emissions. Identifying the location and emission rate of abandoned wells will not only mitigate a potential regionally important methane source, but will also help prevent interactions of these older wells with new drilling for shale gas as well as groundwater.

  19. Zero Valent Iron Significantly Enhances Methane Production from Waste Activated Sludge by Improving Biochemical Methane Potential Rather Than Hydrolysis Rate

    Science.gov (United States)

    Liu, Yiwen; Wang, Qilin; Zhang, Yaobin; Ni, Bing-Jie

    2015-02-01

    Anaerobic digestion has been widely applied for waste activated sludge (WAS) treatment. However, methane production from anaerobic digestion of WAS is usually limited by the slow hydrolysis rate and/or poor biochemical methane potential of WAS. This work systematically studied the effects of three different types of zero valent iron (i.e., iron powder, clean scrap and rusty scrap) on methane production from WAS in anaerobic digestion, by using both experimental and mathematical approaches. The results demonstrated that both the clean and the rusty iron scrap were more effective than the iron powder for improving methane production from WAS. Model-based analysis showed that ZVI addition significantly enhanced methane production from WAS through improving the biochemical methane potential of WAS rather than its hydrolysis rate. Economic analysis indicated that the ZVI-based technology for enhancing methane production from WAS is economically attractive, particularly considering that iron scrap can be freely acquired from industrial waste. Based on these results, the ZVI-based anaerobic digestion process of this work could be easily integrated with the conventional chemical phosphorus removal process in wastewater treatment plant to form a cost-effective and environment-friendly approach, enabling maximum resource recovery/reuse while achieving enhanced methane production in wastewater treatment system.

  20. Zero valent iron significantly enhances methane production from waste activated sludge by improving biochemical methane potential rather than hydrolysis rate.

    Science.gov (United States)

    Liu, Yiwen; Wang, Qilin; Zhang, Yaobin; Ni, Bing-Jie

    2015-02-05

    Anaerobic digestion has been widely applied for waste activated sludge (WAS) treatment. However, methane production from anaerobic digestion of WAS is usually limited by the slow hydrolysis rate and/or poor biochemical methane potential of WAS. This work systematically studied the effects of three different types of zero valent iron (i.e., iron powder, clean scrap and rusty scrap) on methane production from WAS in anaerobic digestion, by using both experimental and mathematical approaches. The results demonstrated that both the clean and the rusty iron scrap were more effective than the iron powder for improving methane production from WAS. Model-based analysis showed that ZVI addition significantly enhanced methane production from WAS through improving the biochemical methane potential of WAS rather than its hydrolysis rate. Economic analysis indicated that the ZVI-based technology for enhancing methane production from WAS is economically attractive, particularly considering that iron scrap can be freely acquired from industrial waste. Based on these results, the ZVI-based anaerobic digestion process of this work could be easily integrated with the conventional chemical phosphorus removal process in wastewater treatment plant to form a cost-effective and environment-friendly approach, enabling maximum resource recovery/reuse while achieving enhanced methane production in wastewater treatment system.

  1. Microbial Methane Oxidation Processes and Technologies for Mitigation of Landfill Gas Emissions

    Science.gov (United States)

    The aim of this paper is to review the present knowledge regarding the microbial methane oxidation in natural or engineered landfill environments with focus on process understanding, engineering experiences and modeling. This review includes seven sections. First, the methane oxidation is put in con...

  2. Landfill methane emission mitigation – How to construct and document a full‐scale biocover system

    DEFF Research Database (Denmark)

    Kjeldsen, Peter; Scheutz, Charlotte

    2014-01-01

    Landfills receiving organic wastes produce biogas (landfill gas – LFG) containing methane (CH4). Landfills are significant sources of methane, which contributes to climate change. As an alternative to gas utilization systems or as a follow‐on technology when a gas utilization system gets non...... rate can be obtained in soils, compost and other materials, high enough to significant reduce the methane emission from landfills. The process has been scaled up by DTU Environment to a full‐scale implemented technology at two Danish landfills. Now the Danish government has decided to establish bio...

  3. Mitigating methane emission from paddy soil with rice-straw biochar amendment under projected climate change

    Science.gov (United States)

    Han, Xingguo; Sun, Xue; Wang, Cheng; Wu, Mengxiong; Dong, Da; Zhong, Ting; Thies, Janice E.; Wu, Weixiang

    2016-04-01

    Elevated global temperatures and increased concentrations of carbon dioxide (CO2) in the atmosphere associated with climate change will exert profound effects on rice cropping systems, particularly on their greenhouse gas emitting potential. Incorporating biochar into paddy soil has been shown previously to reduce methane (CH4) emission from paddy rice under ambient temperature and CO2. We examined the ability of rice straw-derived biochar to reduce CH4 emission from paddy soil under elevated temperature and CO2 concentrations expected in the future. Adding biochar to paddy soil reduced CH4 emission under ambient conditions and significantly reduced emissions by 39.5% (ranging from 185.4 mg kg‑1 dry weight soil, dws season‑1 to 112.2 mg kg‑1 dws season‑1) under simultaneously elevated temperature and CO2. Reduced CH4 release was mainly attributable to the decreased activity of methanogens along with the increased CH4 oxidation activity and pmoA gene abundance of methanotrophs. Our findings highlight the valuable services of biochar amendment for CH4 control from paddy soil in a future that will be shaped by climate change.

  4. Mitigating nitrous oxide and methane emissions from soil in rice-wheat system of the Indo-Gangetic plain with nitrification and urease inhibitors.

    Science.gov (United States)

    Malla, G; Bhatia, Arti; Pathak, H; Prasad, S; Jain, Niveta; Singh, J

    2005-01-01

    Mitigation of methane (CH4) and nitrous oxide (N2O) emissions from soil is important to reduce the global warming. Efficacy of five nitrification inhibitors, i.e. neem (Azadirachta melia) cake, thiosulphate, coated calcium carbide, neem oil coated urea and dicyandiamide (DCD) and one urease inhibitor, hydroquinone, in mitigating N2O and CH4 emissions from fertilized soil was tested in rice-wheat system in the Indo-Gangetic plains. The closed chamber technique was used for the collection of gas samples, which were analyzed using gas chromatography. Reduction in N2O emission on the application of nitrification/urease inhibitors along with urea ranged from 5% with hydroquinone to 31% with thiosulphate in rice and 7% with hydroquinone to 29% with DCD in wheat crop. The inhibitors also influenced the emission of CH4. While application of neem coated urea, coated calcium carbide, neem oil and DCD reduced the emission of CH4; hydroquinone and thiosulphate increased the emission when compared to urea alone. However, the global warming potential was lower with the inhibitors (except hydroquinone) as compared to urea alone, suggesting that these substances could be used for mitigating greenhouse gas emission from the rice-wheat systems.

  5. Potential Cost-Effective Opportunities for Methane Emission Abatement

    Energy Technology Data Exchange (ETDEWEB)

    Warner, Ethan [Joint Inst. for Strategic Energy Analysis, Golden, CO (United States); Steinberg, Daniel [Joint Inst. for Strategic Energy Analysis, Golden, CO (United States); Hodson, Elke [U.S. Department of Energy, Washington, DC (United States); Heath, Garvin [Joint Inst. for Strategic Energy Analysis, Golden, CO (United States)

    2015-08-01

    The energy sector was responsible for approximately 84% of carbon dioxide equivalent (CO2e) greenhouse gas (GHG) emissions in the U.S. in 2012 (EPA 2014a). Methane is the second most important GHG, contributing 9% of total U.S. CO2e emissions. A large portion of those methane emissions result from energy production and use; the natural gas, coal, and oil industries produce approximately 39% of anthropogenic methane emissions in the U.S. As a result, fossil-fuel systems have been consistently identified as high priority sectors to contribute to U.S. GHG reduction goals (White House 2015). Only two studies have recently attempted to quantify the abatement potential and cost associated with the breadth of opportunities to reduce GHG emissions within natural gas, oil, and coal supply chains in the United States, namely the U.S. Environmental Protection Agency (EPA) (2013a) and ICF (2014). EPA, in its 2013 analysis, estimated the marginal cost of abatement for non-CO2 GHG emissions from the natural gas, oil, and coal supply chains for multiple regions globally, including the United States. Building on this work, ICF International (ICF) (2014) provided an update and re-analysis of the potential opportunities in U.S. natural gas and oil systems. In this report we synthesize these previously published estimates as well as incorporate additional data provided by ICF to provide a comprehensive national analysis of methane abatement opportunities and their associated costs across the natural gas, oil, and coal supply chains. Results are presented as a suite of marginal abatement cost curves (MACCs), which depict the total potential and cost of reducing emissions through different abatement measures. We report results by sector (natural gas, oil, and coal) and by supply chain segment - production, gathering and boosting, processing, transmission and storage, or distribution - to facilitate identification of which sectors and supply chain

  6. Mitigation of methane emissions in a pilot-scale biocover system at the AV Miljø Landfill, Denmark: 2. Methane oxidation

    DEFF Research Database (Denmark)

    Scheutz, Charlotte; Cassini, Filippo; De Schoenmaeker, Jan

    2017-01-01

    Greenhouse gas mitigation at landfills by methane (CH4) oxidation in engineered biocover systems is believed to be a cost effective technology but so far a full quantitative evaluation of the efficiency of the technology in full scale has only been carried out in a few cases. A third generation...... semi-passive biocover system was constructed at the AV Miljø Landfill, Denmark. The biocover was fed by landfill gas pumped out of three leachate collection wells. An innovative gas distribution system was used to overcome the often observed uneven gas distribution to the active CH4 oxidation layer...... methods; the carbon mass balance method (based on CH4 and carbon dioxide (CO2) concentrations in the deeper part of the cover and CH4 and CO2 surface flux measurements) and a new-developed tracer gas mass balance method (based on CH4 and tracer inlet fluxes and CH4 and tracer surface flux measurements...

  7. In vitro Screening of Essential Oil Active Compounds for Manipulation of Rumen Fermentation and Methane Mitigation.

    Science.gov (United States)

    Joch, M; Cermak, L; Hakl, J; Hucko, B; Duskova, D; Marounek, M

    2016-07-01

    The objective of this study was to investigate the effects of 11 active compounds of essential oils (ACEO) on rumen fermentation characteristics and methane production. Two trials were conducted. In trial 1, ACEO (eugenol, carvacrol, citral, limonene, 1,4-cineole, p-cymene, linalool, bornyl acetate, α-pinene, and β-pinene) at a dose of 1,000 μL/L were incubated for 24 h in diluted rumen fluid with a 70:30 forage:concentrate substrate (16.2% crude protein; 36.6% neutral detergent fiber). Three fistulated Holstein cows were used as donors of rumen fluid. The reduction in methane production was observed with nine ACEO (up to 86% reduction) compared with the control (pproduction, and only bornyl acetate produced less methane per mol of VFA compared with the control (pproduction of two concentrations (500 and 2,000 μL/L) of bornyl acetate, the most promising ACEO from the first trial, were evaluated using the same in vitro incubation method that was used in the first trial. In trial 2, monensin was used as a positive control. Both doses of bornyl acetate decreased (pproduction and did not inhibit VFA production. Positive effects of bornyl acetate on methane and VFA production were more pronounced than the effects of monensin. These results confirm the ability of bornyl acetate to decrease methane production, which may help to improve the efficiency of energy use in the rumen.

  8. Special topics--Mitigation of methane and nitrous oxide emissions from animal operations: II. A review of manure management mitigation options.

    Science.gov (United States)

    Montes, F; Meinen, R; Dell, C; Rotz, A; Hristov, A N; Oh, J; Waghorn, G; Gerber, P J; Henderson, B; Makkar, H P S; Dijkstra, J

    2013-11-01

    This review analyzes published data on manure management practices used to mitigate methane (CH4) and nitrous oxide (N2O) emissions from animal operations. Reducing excreted nitrogen (N) and degradable organic carbon (C) by diet manipulation to improve the balance of nutrient inputs with production is an effective practice to reduce CH4 and N2O emissions. Most CH4 is produced during manure storage; therefore, reducing storage time, lowering manure temperature by storing it outside during colder seasons, and capturing and combusting the CH4 produced during storage are effective practices to reduce CH4 emission. Anaerobic digestion with combustion of the gas produced is effective in reducing CH4 emission and organic C content of manure; this increases readily available C and N for microbial processes creating little CH4 and increased N2O emissions following land application. Nitrous oxide emission occurs following land application as a byproduct of nitrification and dentrification processes in the soil, but these processes may also occur in compost, biofilter materials, and permeable storage covers. These microbial processes depend on temperature, moisture content, availability of easily degradable organic C, and oxidation status of the environment, which make N2O emissions and mitigation results highly variable. Managing the fate of ammoniacal N is essential to the success of N2O and CH4 mitigation because ammonia is an important component in the cycling of N through manure, soil, crops, and animal feeds. Manure application techniques such as subsurface injection reduce ammonia and CH4 emissions but can result in increased N2O emissions. Injection works well when combined with anaerobic digestion and solids separation by improving infiltration. Additives such as urease and nitrification inhibitors that inhibit microbial processes have mixed results but are generally effective in controlling N2O emission from intensive grazing systems. Matching plant nutrient

  9. CO2 mitigation potential in farmland of China by altering current organic matter amendment pattern

    Institute of Scientific and Technical Information of China (English)

    CADISCH; Georg

    2010-01-01

    The estimation of the global warming mitigation potential in terrestrial ecosystems is of great importance for decision makers to adopt measures to increase soil organic carbon (SOC) as well as to reduce greenhouse gas (GHGs) emissions. In this paper, we compiled data published in peer-reviewed journals, and conducted a holistic analysis of the effects of organic matter amendment on soil organic carbon sequestration, methane (CH4) and nitrous oxide (N2O) emissions in paddy and upland systems. Results showed that organic matter amendment increased soil organic carbon content, and apparent conversion rate of organic matter carbon to soil organic carbon in paddies was constant, while that in uplands decreased along with amendment years at 25 years time scale. Organic matter amendment during the rice season led to large CH4-C emissions, e.g on average 99.5 g CH4-C per kg organic carbon input under intermittent flood conditions, and 191.7 g CH4-C per kg organic carbon input under continuous flood conditions, respectively. By alteration of organic matter amendment from rice season to off-rice upland crop season, estimated CH4-C emissions in China could be cut by 3.5 Tg yr-1, accounting for 63% of current CH4-C emissions (5.5 Tg). If organic matter amendment percentage was increased from current 30% to future 50% of organic matter production and by alteration of organic matter amendment from rice season to off-rice upland crop season, the equivalent CO2-C mitigation potential in farmland of China would be 49.2 Tg yr-1 at the 10th year organic matter amendment and 36.0 Tg yr-1 at the 30th year amendment. These findings are important not only for China but also for the other rice production countries to increase farmland global warming mitigation.

  10. Do mitigation strategies reduce global warming potential in the northern U.S. corn belt?

    Science.gov (United States)

    Johnson, Jane M-F; Archer, David W; Weyers, Sharon L; Barbour, Nancy W

    2011-01-01

    Agricultural management practices that enhance C sequestration, reduce greenhouse gas emission (nitrous oxide [N₂O], methane [CH₄], and carbon dioxide [CO₂]), and promote productivity are needed to mitigate global warming without sacrificing food production. The objectives of the study were to compare productivity, greenhouse gas emission, and change in soil C over time and to assess whether global warming potential and global warming potential per unit biomass produced were reduced through combined mitigation strategies when implemented in the northern U.S. Corn Belt. The systems compared were (i) business as usual (BAU); (ii) maximum C sequestration (MAXC); and (iii) optimum greenhouse gas benefit (OGGB). Biomass production, greenhouse gas flux change in total and organic soil C, and global warming potential were compared among the three systems. Soil organic C accumulated only in the surface 0 to 5 cm. Three-year average emission of N₂O and CH was similar among all management systems. When integrated from planting to planting, N₂O emission was similar for MAXC and OGGB systems, although only MAXC was fertilized. Overall, the three systems had similar global warming potential based on 4-yr changes in soil organic C, but average rotation biomass was less in the OGGB systems. Global warming potential per dry crop yield was the least for the MAXC system and the most for OGGB system. This suggests management practices designed to reduce global warming potential can be achieved without a loss of productivity. For example, MAXC systems over time may provide sufficient soil C sequestration to offset associated greenhouse gas emission. by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  11. Persistency of methane mitigation by dietary nitrate supplementation in dairy cows

    NARCIS (Netherlands)

    Zijderveld, van S.M.; Gerrits, W.J.J.; Dijkstra, J.; Newbold, J.R.; Hulshof, R.B.A.; Perdok, H.B.

    2011-01-01

    Feeding nitrate to dairy cows may lower ruminal methane production by competing for reducing equivalents with methanogenesis. Twenty lactating Holstein-Friesian dairy cows (33.2±6.0 kg of milk/d; 104±58 d in milk at the start of the experiment) were fed a total mixed ration (corn silage-based; forag

  12. In vivo and in vitro effects of a blend of essential oils on rumen methane mitigation

    NARCIS (Netherlands)

    Castro-Montoya, J.; Peiren, N.; Cone, J.W.; Zweifel, B.; Fievez, V.; Campeneere, De S.

    2015-01-01

    The effect of Agolin Ruminant, a blend of essential oils, on methane (CH4) emissions were investigated in two in vivo experiments and in four in vitro experiments. In the in vivo experiments, four lactating dairy cows and four beef heifers were supplemented 0.2 g/d of the essential oils (ca. 2–4 ppm

  13. In vivo and in vitro effects of a blend of essential oils on rumen methane mitigation

    NARCIS (Netherlands)

    Castro-Montoya, J.; Peiren, N.; Cone, J.W.; Zweifel, B.; Fievez, V.; Campeneere, De S.

    2015-01-01

    The effect of Agolin Ruminant, a blend of essential oils, on methane (CH4) emissions were investigated in two in vivo experiments and in four in vitro experiments. In the in vivo experiments, four lactating dairy cows and four beef heifers were supplemented 0.2 g/d of the essential oils (ca. 2–4 ppm

  14. Key factors influencing the potential of catch crops for methane production

    DEFF Research Database (Denmark)

    Molinuevo-Salces, Beatriz; Fernandez-Varela, Raquel; Uellendahl, Hinrich

    2014-01-01

    Catch crops are grown in crop rotation primarily for soil stabilization. The excess biomass of catch crops was investigated for its potential as feedstock for biogas production. Ten variables affecting catch crop growth and methane potential were evaluated. Field trials and methane potential were...

  15. Mitigation of methane production from cattle by feeding cashew nut shell liquid.

    Science.gov (United States)

    Shinkai, T; Enishi, O; Mitsumori, M; Higuchi, K; Kobayashi, Y; Takenaka, A; Nagashima, K; Mochizuki, M; Kobayashi, Y

    2012-09-01

    The effects of cashew nut shell liquid (CNSL) feeding on methane production and rumen fermentation were investigated by repeatedly using 3 Holstein nonlactating cows with rumen fistulas. The cows were fed a concentrate and hay diet (6:4 ratio) for 4 wk (control period) followed by the same diet with a CNSL-containing pellet for the next 3 wk (CNSL period). Two trials were conducted using CNSL pellets blended with only silica (trial 1) or with several other ingredients (trial 2). Each pellet type was fed to cows to allow CNSL intake at 4 g/100 kg of body weight per day. Methane production was measured in a respiration chamber system, and energy balance, nutrient digestibility, and rumen microbial changes were monitored. Methane production per unit of dry matter intake decreased by 38.3 and 19.3% in CNSL feeding trials 1 and 2, respectively. Energy loss as methane emission decreased from 9.7 to 6.1% (trial 1) and from 8.4 to 7.0% (trial 2) with CNSL feeding, whereas the loss to feces (trial 1) and heat production (trial 2) increased. Retained energy did not differ between the control and CNSL periods. Digestibility of dry matter and gross energy decreased with CNSL feeding in trial 1, but did not differ in trial 2. Feeding CNSL caused a decrease in acetate and total short-chain fatty acid levels and an increase in propionate proportion in both trials. Relative copy number of methyl coenzyme-M reductase subunit A gene and its expression decreased with CNSL feeding. The relative abundance of fibrolytic or formate-producing species such as Ruminococcus flavefaciens, Butyrivibrio fibrisolvens, and Treponema bryantii decreased, but species related to propionate production, including Prevotella ruminicolla, Selenomonas ruminantium, Anaerovibrio lipolytica, and Succinivibrio dextrinosolvens, increased. If used in a suitable formulation, CNSL acts as a potent methane-inhibiting and propionate-enhancing agent through the alteration of rumen microbiota without adversely

  16. Tropical tanniniferous legumes used as an option to mitigate sheep enteric methane emission.

    Science.gov (United States)

    Moreira, Guilherme Dias; Lima, Paulo de Mello Tavares; Borges, Bárbara Oliveira; Primavesi, Odo; Longo, Cibele; McManus, Concepta; Abdalla, Adibe; Louvandini, Helder

    2013-03-01

    This study presents the first results from Brazil using SF(6) tracer technique adapted from cattle to evaluate the capability of condensed tannin (CT) present in three tropical legume forages, Leucaena leucocephala (LEU), Styzolobium aterrimum (STA), and Mimosa caesalpiniaefolia Benth (MIM) to reduce enteric CH(4) production in Santa Inês sheep. Twelve male lambs [27.88 ± 2.85 kg body weight (BW)] were allocated in individual metabolic cages for 20-day adaptation followed by 6 days for measuring dry matter intake (DMI) and CH(4) emission. All lambs received water, mineral supplement, and Cynodon dactylon v. coast-cross hay ad libitum. The treatments consisted of soybean meal (710 g/kg) and ground corn (290 g/kg) [control (CON)]; soybean meal (150 g/kg), ground corn (30 g/kg), and Leucaena hay (820 g/kg) (LEU); soybean meal (160 g/kg), ground corn (150 g/kg), and Mucuna hay (690 g/kg) (STA); and soybean meal (280 g/kg), ground corn (190 g/kg), and Mimosa hay (530 g/kg) (MIM); all calculated to provide 40 g/kg CT (except for CON). DMI (in grams of DMI per kilogram BW per day) was lower for LEU (22.0) than CON (29.3), STA (31.2), and MIM (31.6). The LEU group showed emission of 7.8 g CH(4)/day, significantly lower than CON (10.5 g CH(4)/day), STA (10.4 g CH(4)/day), and MIM (11.3 g CH(4)/day). However, when the CH(4) emission per DMI was considered, there were no significant differences among treatments (0.37, 0.36, 0.33, and 0.35 g CH(4)/g DMI/kg BW/day, respectively, for CON, LEU, STA, and MIM). The sheep receiving STA had shown a tendency (p = 0.15) to reduce methane emission when compared to the CON group. Therefore, it is suggested that tropical tanniniferous legumes may have potential to reduce CH(4) emission in sheep, but more research is warranted to confirm these results.

  17. Genetic parameters for predicted methane production and potential for reducing enteric emissions through genomic selection

    NARCIS (Netherlands)

    Haas, de Y.; Windig, J.J.; Calus, M.P.L.; Dijkstra, J.; Haan, de M.H.A.; Bannink, A.; Veerkamp, R.F.

    2011-01-01

    Mitigation of enteric methane (CH4) emission in ruminants has become an important area of research because accumulation of CH4 is linked to global warming. Nutritional and microbial opportunities to reduce CH4 emissions have been extensively researched, but little is known about using natural

  18. Alaska coal geology, resources, and coalbed methane potential

    Science.gov (United States)

    Flores, Romeo M.; Stricker, Gary D.; Kinney, Scott A.

    2004-01-01

    Estimated Alaska coal resources are largely in Cretaceous and Tertiary rocks distributed in three major provinces. Northern Alaska-Slope, Central Alaska-Nenana, and Southern Alaska-Cook Inlet. Cretaceous resources, predominantly bituminous coal and lignite, are in the Northern Alaska-Slope coal province. Most of the Tertiary resources, mainly lignite to subbituminous coal with minor amounts of bituminous and semianthracite coals, are in the other two provinces. The combined measured, indicated, inferred, and hypothetical coal resources in the three areas are estimated to be 5,526 billion short tons (5,012 billion metric tons), which constitutes about 87 percent of Alaska's coal and surpasses the total coal resources of the conterminous United States by 40 percent. Coal mining has been intermittent in the Central Alaskan-Nenana and Southern Alaska-Cook Inlet coal provinces, with only a small fraction of the identified coal resource having been produced from some dozen underground and strip mines in these two provinces. Alaskan coal resources have a lower sulfur content (averaging 0.3 percent) than most coals in the conterminous United States are within or below the minimum sulfur value mandated by the 1990 Clean Air Act amendments. The identified resources are near existing and planned infrastructure to promote development, transportation, and marketing of this low-sulfur coal. The relatively short distances to countries in the west Pacific Rim make them more exportable to these countries than to the lower 48 States of the United States. Another untapped but potential resource of large magnitude is coalbed methane, which has been estimated to total 1,000 trillion cubic feet (28 trillion cubic meters) by T.N. Smith 1995, Coalbed methane potential for Alaska and drilling results for the upper Cook Inlet Basin: Intergas, May 15 - 19, 1995, Tuscaloosa, University of Alabama, p. 1 - 21.

  19. Potentials and risks of utilizing methane from methane hydrate as an energy support; Potentiale und Risiken der Nutzung von Methan aus Methandhydraten als Energietraeger

    Energy Technology Data Exchange (ETDEWEB)

    Groth, Markus [Lueneburg Univ. (Germany). Lehrstuhl fuer Nachhaltigkeitsoekonomie

    2009-10-15

    Marine and permafrost-based methane hydrates are the largest existing fossil carbon resource, whereby the marine deposits far outweigh the terrestrial ones. Their broad geographic distribution, especially in comparison to oil and conventional gas, make them a promising future source of energy. However, there is a danger of forcing the greenhouse effect in the event of a release of methane into the atmosphere as well as causing the collapse of oceanic slope sediments. Also the technical difficulties in extracting methane from hydrates are not yet fully resolved. Nevertheless, research on methane hydrates has been forced both on political as well as economic considerations in recent years and methane hydrates have several practical advantages, which make them a transitional solution worth looking at on the way to a future renewable-based energy supply, not in the least in playing a role in carbon capture and sequestration. However, the knowledge of the potentials and risks of methane hydrates is still very poor, especially in the German-speaking public, administration and policies. This deficiency hopefully will be eased by this overview dealing with the current state of research and an outlook based on the most important findings. (orig.)

  20. Groundwater methane in a potential coal seam gas extraction region

    Directory of Open Access Journals (Sweden)

    Marnie L. Atkins

    2015-09-01

    New hydrological insights for the region: Methane was found in all geological units ranging between 0.26 and 4427 μg L−1 (median 10.68 μg L−1. Median methane concentrations were highest in chloride-type groundwater (13.26 μg L−1, n = 58 while bicarbonate-type groundwater had lower concentrations (3.71 μg L−1. Groundwater from alluvial sediments had significantly higher median methane concentrations (91.46 μg L−1 than groundwater from both the basalt aquifers (0.7 μg L−1 and bedrock aquifers (4.63 μg L−1; indicating geology was a major driver of methane distribution. Methane carbon stable isotope ratios ranged from –90.9‰ to –29.5‰, suggesting a biogenic origin with some methane oxidation. No significant correlations were observed between methane concentrations and redox indicators (nitrate, manganese, iron and sulphate except between iron and methane in the Lismore Basalt (r2 = 0.66, p < 0.001, implying redox conditions were not the main predictor of methane distribution.

  1. Mitigation of methane emissions in a pilot-scale biocover system at the av miljø landfill, denmark: system design and gas distribution

    DEFF Research Database (Denmark)

    Kjeldsen, Peter; Skov, B.; Cassini, Filippo

    2013-01-01

    Greenhouse gas mitigation at landfills by methane oxidation in engineered biocover systems is believed to be a cost effective technology but so far a full quantitative evaluation of the efficiency of the technology in full scale has only been carried out in a few cases. A third generation semi-pa...

  2. Global warming mitigation potential of biogas plants in India.

    Science.gov (United States)

    Pathak, H; Jain, N; Bhatia, A; Mohanty, S; Gupta, Navindu

    2009-10-01

    Biogas technology, besides supplying energy and manure, provides an excellent opportunity for mitigation of greenhouse gas (GHG) emission and reducing global warming through substituting firewood for cooking, kerosene for lighting and cooking and chemical fertilizers. A study was undertaken to calculate (1) global warming mitigation potential (GMP) and thereby earning carbon credit of a family size biogas plant in India, (2) GMP of the existing and target biogas plants in the country and (3) atmospheric pollution reduction by a family size biogas plant. The GMP of a family size biogas plant was 9.7 t CO(2) equiv. year( - 1) and with the current price of US $10 t( - 1) CO(2) equiv., carbon credit of US $97 year( - 1) could be earned from such reduction in greenhouse gas emission under the clean development mechanism (CDM). A family size biogas plant substitutes 316 L of kerosene, 5,535 kg firewood and 4,400 kg cattle dung cake as fuels which will reduce emissions of NOx, SO(2), CO and volatile organic compounds to the atmosphere by 16.4, 11.3, 987.0 and 69.7 kg year( - 1), respectively. Presently 3.83 million biogas plants are operating in the country, which can mitigate global warming by 37 Mt CO(2) equiv. year( - 1). Government of India has a target of installing 12.34 million biogas plants by 2010. This target has a GMP of 120 Mt CO(2) equiv. year( - 1) and US $1,197 million as carbon credit under the CDM. However, if all the collectible cattle dung (225 Mt) produced in the country is used, 51.2 million family size biogas plants can be supported which will have a GMP of 496 Mt of CO(2) equiv. year( - 1) and can earn US $4,968 million as carbon credit. The reduction in global warming should encourage policy makers to promote biogas technology to combat climate change and integration of carbon revenues will help the farmers to develop biogas as a profitable activity.

  3. Technical options for the mitigation of direct methane and nitrous oxide emissions from livestock: a review

    NARCIS (Netherlands)

    Gerber, P.J.; Hristov, A.N.; Henderson, B.L.; Makkar, H.P.S.; Oh, J.; Lee, C.; Meinen, R.; Montes, F.; Ott, T.; Firkins, J.; Rotz, A.; Dell, C.; Adesogan, A.T.; Yang, W.Z.; Tricarico, J.M.; Kebreab, E.; Waghorn, G.; Dijkstra, J.; Oosting, S.J.

    2013-01-01

    Although livestock production accounts for a sizeable share of global greenhouse gas emissions, numerous technical options have been identified to mitigate these emissions. In this review, a subset of these options, which have proven to be effective, are discussed. These include measures to reduce C

  4. Maize silage for dairy cows: mitigation of methane emissions can be offset bij and use change

    NARCIS (Netherlands)

    Vellinga, Th.V.; Hoving, I.E.

    2011-01-01

    Increasing the digestibility of cattle rations by feeding grains and whole plant silages from maize have been identified as effective options to mitigate greenhouse gas emissions. The effect of ploughing grassland for maize crops have not been taken into account yet. A intensive dairy farm is used

  5. Potential for reduction of methane emissions from dairy cows

    DEFF Research Database (Denmark)

    Johannes, Maike; Hellwing, Anne Louise Frydendahl; Lund, Peter

    2010-01-01

    , while fibre and sugar enhance methane emissions. Fat can be regarded as the most promising feed additive at the moment. At AU, respiration chambers have been installed to enable methane measurements from dairy cows combined with digestibility trials, and at present studies are being conducted concerning...

  6. Effects of different types of biochar on methane and ammonia mitigation during layer manure composting.

    Science.gov (United States)

    Chen, Wei; Liao, Xindi; Wu, Yinbao; Liang, Juan Boo; Mi, Jiandui; Huang, Jinjie; Zhang, Heng; Wu, Yu; Qiao, Zhifen; Li, Xi; Wang, Yan

    2017-03-01

    Biochar, because of its unique physiochemical properties and sorption capacity, may be an ideal amendment in reducing gaseous emissions during composting process but there has been little information on the potential effects of different types of biochar on undesired gaseous emissions. The objective of this study was to examine the ability and mechanism of different types of biochar, as co-substrate, in mitigating gaseous emission from composting of layer hen manure. The study was conducted in small-scale laboratory composters with the addition of 10% of one of the following biochars: cornstalk biochar, bamboo biochar, woody biochar, layer manure biochar and coir biochar. The results showed that the cumulative NH3 production was significantly reduced by 24.8±2.9, 9.2±1.3, 20.1±2.6, 14.2±1.6, 11.8±1.7% (corrected for initial total N) in the cornstalk biochar, bamboo biochar, woody biochar, layer manure biochar and coir biochar treatments, respectively, compared to the control. Total CH4 emissions was significantly reduced by 26.1±2.3, 15.5±2.1, 22.4±3.1, 17.1±2.1% (corrected for the initial total carbon) for cornstalk biochar, bamboo biochar, woody biochar and coir biochar treatments than the control. Moreover, addition of cornstalk biochar increased the temperature and NO3(-)-N concentration and decreased the pH, NH4(+)-N and organic matter content throughout the composting process. The results suggested that total volatilization of NH3 and CH4 in cornstalk biochar treatment was lower than the other treatments; which could be due to (i) decrease of pH and higher nitrification, (ii) high sorption capacity for gases and their precursors, such as ammonium nitrogen from composting mixtures, because of the higher surface area, pore volumes, total acidic functional groups and CEC of cornstalk biochar. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Integrated rice-duck farming mitigates the global warming potential in rice season.

    Science.gov (United States)

    Xu, Guochun; Liu, Xin; Wang, Qiangsheng; Yu, Xichen; Hang, Yuhao

    2017-01-01

    Integrated rice-duck farming (IRDF), as a mode of ecological agriculture, is an important way to realize sustainable development of agriculture. A 2-year split-plot field experiment was performed to evaluate the effects of IRDF on methane (CH4) and nitrous oxide (N2O) emissions and its ecological mechanism in rice season. This experiment was conducted with two rice farming systems (FS) of IRDF and conventional farming (CF) under four paddy-upland rotation systems (PUR): rice-fallow (RF), annual straw incorporating in rice-wheat rotation system (RWS), annual straw-based biogas residues incorporating in rice-wheat rotation system (RWB), and rice-green manure (RGM). During the rice growing seasons, IRDF decreased the CH4 emission by 8.80-16.68%, while increased the N2O emission by 4.23-15.20%, when compared to CF. Given that CH4 emission contributed to 85.83-96.22% of global warming potential (GWP), the strong reduction in CH4 emission led to a significantly lower GWP of IRDF as compared to CF. The reason for this trend was because IRDF has significant effect on dissolved oxygen (DO) and soil redox potential (Eh), which were two pivotal factors for CH4 and N2O emissions in this study. The IRDF not only mitigates the GWP, but also increases the rice yield by 0.76-2.43% compared to CF. Moreover, compared to RWS system, RF, RWB and RGM systems significantly reduced CH4 emission by 50.17%, 44.89% and 39.51%, respectively, while increased N2O emission by 10.58%, 14.60% and 23.90%, respectively. And RWS system had the highest GWP. These findings suggest that mitigating GWP and improving rice yield could be simultaneously achieved by the IRDF, and employing suitable PUR would benefit for relieving greenhouse effect. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Key factors influencing the potential of catch crops for methane production.

    Science.gov (United States)

    Molinuevo-Salces, Beatriz; Fernández-Varela, Raquel; Uellendahl, Hinrich

    2014-08-01

    Catch crops are grown in crop rotation primarily for soil stabilization. The excess biomass of catch crops was investigated for its potential as feedstock for biogas production. Ten variables affecting catch crop growth and methane potential were evaluated. Field trials and methane potential were studied for 14 different catch crops species, with 19 samples harvested in 2010 and 36 harvested in 2011. Principal component analysis was applied to the data to identify the variables characterizing the potential for the different catch crops species for methane production. Two principal components explained up to 84.6% and 71.6% of the total variation for 2010 and 2011 samples, respectively. Specific methane yield, climate conditions (rainfall and temperature) and total nitrogen in the biomass were the variables classifying the different catch crops. Catch crops in the Brassicaceae and Graminaceae botanical families showed the highest methane yield. This study demonstrates the importance of the crop species when choosing a suitable catch crop for biogas production.

  9. Bioassay for estimating the biogenic methane-generating potential of coal samples

    Science.gov (United States)

    Jones, E.J.P.; Voytek, M.A.; Warwick, P.D.; Corum, M.D.; Cohn, A.; Bunnell, J.E.; Clark, A.C.; Orem, W.H.

    2008-01-01

    Generation of secondary biogenic methane in coal beds is likely controlled by a combination of factors such as the bioavailability of coal carbon, the presence of a microbial community to convert coal carbon to methane, and an environment supporting microbial growth and methanogenesis. A set of treatments and controls was developed to bioassay the bioavailability of coal for conversion to methane under defined laboratory conditions. Treatments included adding a well-characterized consortium of bacteria and methanogens (enriched from modern wetland sediments) and providing conditions to support endemic microbial activity. The contribution of desorbed methane in the bioassays was determined in treatments with bromoethane sulfonic acid, an inhibitor of microbial methanogenesis. The bioassay compared 16 subbituminous coal samples collected from beds in Texas (TX), Wyoming (WY), and Alaska (AK), and two bituminous coal samples from Pennsylvania (PA). New biogenic methane was observed in several samples of subbituminous coal with the microbial consortium added, but endemic activity was less commonly observed. The highest methane generation [80????mol methane/g coal (56??scf/ton or 1.75??cm3/g)] was from a south TX coal sample that was collected from a non-gas-producing well. Subbituminous coals from the Powder River Basin, WY and North Slope Borough, AK contained more sorbed (original) methane than the TX coal sample and generated 0-23????mol/g (up to 16??scf/ton or 0.5??cm3/g) new biogenic methane in the bioassay. Standard indicators of thermal maturity such as burial depth, nitrogen content, and calorific value did not explain differences in biogenic methane among subbituminous coal samples. No original methane was observed in two bituminous samples from PA, nor was any new methane generated in bioassays of these samples. The bioassay offers a new tool for assessing the potential of coal for biogenic methane generation, and provides a platform for studying the

  10. Biochemical methane potential (BMP) of solid organic materials

    DEFF Research Database (Denmark)

    Raposo, Francisco; Fernández-Cegrí, V.; De la Rubia, M.A.

    2010-01-01

    and experimental conditions were reported. The study was performed using 4 samples: 3 reference substrates (starch, cellulose and gelatine), and 1 raw material (mung bean). The BMP of mung bean was carried out at two inoculum to substrate ratios (ISR), specifically 2 and 1. The methane yields of reference...... substrates for starch, cellulose and gelatine were 352±33, 353±29 and 382±42 mL/g VSadded, respectively. The percentages of biotransformation of these substrates into methane were 85±8, 85±7 and 88±10%, respectively. On the other hand, the values of methane yields and biodegradability for MB were 373±35 m...

  11. Exploring the potential roles of biochars on land degradation mitigation

    Directory of Open Access Journals (Sweden)

    A.K. Berek

    2014-04-01

    Full Text Available Land degradation was exacerbated and its management was challenged by population growth and global climate change. The impacts of land degradation on food security, ecosystem services and biodiversity become a more serious problem particularly in developing countries. Biochar, based on the current research findings, is capable to amend degraded lands. This paper reviewed relevant biocharproperties and identified the opportunities of its using for recovering deteriorated lands.Biochar was traditionally recognized as a good absorbent, energy source, and its ash was used by farmers to recover soil fertility. Recent findings revealed that application of biochar improved soil water retention, enhanced soil aggregation, decreased soil bulk density and increased soil infiltration. It also increased soil cation exchange capacity, soil pH, mineral nutrients, reduced nutrient leaching, support microbial population and activities, and suppressed the pest. The sorption capacity of biochar to soil and water pollutants such as Pb, Cu, Ni, Cr, Cd,dioxine, atrazine, and concurrently eliminatedthe environmental problems such as hypoxia, eutrophication, and algae bloom, have also been investigated. Investigation on its role to mitigate climate change revealed that biochar is capable in reducing greenhouse gasesemissions such as CO2, N2O, and CH4. All those beneficial effects of biochars were attributed to its high porosity, large surface area and surface charge, high carbon, ash and nutrient content, and its stability to be degraded. Thus, biochar could be potential for ameliorating degraded lands

  12. Potential of lactic acid bacteria in aflatoxin risk mitigation.

    Science.gov (United States)

    Ahlberg, Sara H; Joutsjoki, Vesa; Korhonen, Hannu J

    2015-08-17

    Aflatoxins (AF) are ubiquitous mycotoxins contaminating food and feed. Consumption of contaminated food and feed can cause a severe health risk to humans and animals. A novel biological method could reduce the health risks of aflatoxins through inhibiting mold growth and binding aflatoxins. Lactic acid bacteria (LAB) are commonly used in fermented food production. LAB are known to inhibit mold growth and, to some extent, to bind aflatoxins in different matrices. Reduced mold growth and aflatoxin production may be caused by competition for nutrients between bacterial cells and fungi. Most likely, binding of aflatoxins depends on environmental conditions and is strain-specific. Killed bacteria cells possess consistently better binding abilities for aflatoxin B1 (AFB1) than viable cells. Lactobacilli especially are relatively well studied and provide noticeable possibilities in binding of aflatoxin B1 and M1 in food. It seems that binding is reversible and that bound aflatoxins are released later on (Haskard et al., 2001; Peltonen et al., 2001). This literature review suggests that novel biological methods, such as lactic acid bacteria, show potential in mitigating toxic effects of aflatoxins in food and feed. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Mitigation of methane emission from Fakse landfill using a biowindow system

    DEFF Research Database (Denmark)

    Scheutz, Charlotte; Fredenslund, Anders Michael; Chanton, Jeffrey

    2011-01-01

    Landfills are significant sources of atmospheric methane (CH4) that contributes to climate change, and therefore there is a need to reduce CH4 emissions from landfills. A promising cost efficient technology is to integrate compost into landfill covers (so-called “biocovers”) to enhance biological...... oxidation of CH4. A full scale biocover system to reduce CH4 emissions was installed at Fakse landfill, Denmark using composted yard waste as active material supporting CH4 oxidation. Ten biowindows with a total area of 5000m2 were integrated into the existing cover at the 12ha site. To increase CH4 load...... to the biowindows, leachate wells were capped, and clay was added to slopes at the site. Point measurements using flux chambers suggested in most cases that almost all CH4 was oxidized, but more detailed studies on emissions from the site after installation of the biocover as well as measurements of total CH4...

  14. Methane flux in potential hydrate-bearing sediments offshore southwestern Taiwan

    Science.gov (United States)

    Chen, Nai-Chen; Yang, Tsanyao Frank; Chuang, Pei-Chuan; Hong, Wei-Li; Chen, Hsuan-Wen; Lin, Saulwood; Lin, Li-Hung; Mastumoto, Ryo; Hiruta, Akihiro; Sun, Chih-Hsien; Wang, Pei-Ling; Yang, Tau; Jiang, Shao-yong; Wang, Yun-shuen; Chung, San-Hsiung; Chen, Cheng-Hong

    2016-04-01

    infiltrating from seawater was consumed by AOM. Gas compositions and methane carbon isotopes show microbial gas dominated at passive margin and lower slope of active margin; by contrast, thermogenic gas source was prevalent at upper slope of active margin. In summary, transport of deeply sourced methane in potential hydrate-bearing sediments is strongly controlled by geological structures and microbial processes. For most of sites, anaerobic and aerobic methanotrophy in sediments act as efficient biofiltration for the removal of methane. For sites with strong fluid advection, a great fraction of deeply-sourced methane could escape from anaerobic and aerobic methanotrophy and be discharged into seawater column. The changing mechanisms for gas generation from passive to active margin highlights the interplay between in situ methanogenesis, sediment loading, and connectivity of fluid conduits.

  15. Mitigation of ammonia, nitrous oxide and methane emissions from manure management chains: a meta-analysis and integrated assessment.

    Science.gov (United States)

    Hou, Yong; Velthof, Gerard L; Oenema, Oene

    2015-03-01

    Livestock manure contributes considerably to global emissions of ammonia (NH3 ) and greenhouse gases (GHG), especially methane (CH4 ) and nitrous oxide (N2 O). Various measures have been developed to mitigate these emissions, but most of these focus on one specific gas and/or emission source. Here, we present a meta-analysis and integrated assessment of the effects of mitigation measures on NH3 , CH4 and (direct and indirect) N2 O emissions from the whole manure management chain. We analysed the effects of mitigation technologies on NH3 , CH4 and N2 O emissions from individual sources statistically using results of 126 published studies. Whole-chain effects on NH3 and GHG emissions were assessed through scenario analysis. Significant NH3 reduction efficiencies were observed for (i) housing via lowering the dietary crude protein (CP) content (24-65%, compared to the reference situation), for (ii) external slurry storages via acidification (83%) and covers of straw (78%) or artificial films (98%), for (iii) solid manure storages via compaction and covering (61%, compared to composting), and for (iv) manure application through band spreading (55%, compared to surface application), incorporation (70%) and injection (80%). Acidification decreased CH4 emissions from stored slurry by 87%. Significant increases in N2 O emissions were found for straw-covered slurry storages (by two orders of magnitude) and manure injection (by 26-199%). These side-effects of straw covers and slurry injection on N2 O emission were relatively small when considering the total GHG emissions from the manure chain. Lowering the CP content of feed and acidifying slurry are strategies that consistently reduce NH3 and GHG emissions in the whole chain. Other strategies may reduce emissions of a specific gas or emissions source, by which there is a risk of unwanted trade-offs in the manure management chain. Proper farm-scale combinations of mitigation measures are important to minimize impacts of

  16. Meta-analysis on Methane Mitigating Properties of Saponin-rich Sources in the Rumen: Influence of Addition Levels and Plant Sources

    Directory of Open Access Journals (Sweden)

    Anuraga Jayanegara

    2014-10-01

    Full Text Available Saponins have been considered as promising natural substances for mitigating methane emissions from ruminants. However, studies reported that addition of saponin-rich sources often arrived at contrasting results, i.e. either it decreased methane or it did not. The aim of the present study was to assess ruminal methane emissions through a meta-analytical approach of integrating related studies from published papers which described various levels of different saponin-rich sources being added to ruminant feed. A database was constructed from published literature reporting the addition of saponin-rich sources at various levels and then monitoring ruminal methane emissions in vitro. Accordingly, levels of saponin-rich source additions as well as different saponin sources were specified in the database. Apart from methane, other related rumen fermentation parameters were also included in the database, i.e. organic matter digestibility, gas production, pH, ammonia concentration, short-chain fatty acid profiles and protozoal count. A total of 23 studies comprised of 89 data points met the inclusion criteria. The data obtained were subsequently subjected to a statistical meta-analysis based on mixed model methodology. Accordingly, different studies were treated as random effects whereas levels of saponin-rich source additions or different saponin sources were considered as fixed effects. Model statistics used were p-value and root mean square error. Results showed that an addition of increasing levels of a saponin-rich source decreased methane emission per unit of substrate incubated as well as per unit of total gas produced (ptea>quillaja, statistically they did not differ each other. It can be concluded that methane mitigating properties of saponins in the rumen are level- and source-dependent.

  17. The potential for biomass to mitigate greenhouse gas emissions in the Northeastern US

    Energy Technology Data Exchange (ETDEWEB)

    Bernow, S.S.; Gurney, K.; Prince, G.; Cyr, M.

    1992-04-01

    This study, for the Northeast Regional Biomass Program (NRBP) of the Coalition of Northeast Governors (CONEG), evaluates the potential for local, state and regional biomass policies to contribute to an overall energy/biomass strategy for the reduction of greenhouse gas releases in the Northeastern United States. Biomass is a conditionally renewable resource that can play a dual role: by reducing emissions of greenhouse gases in meeting our energy needs; and by removing carbon from the atmosphere and sequestering it in standing biomass stocks and long-lived products. In this study we examine the contribution of biomass to the energy system in the Northeast and to the region's net releases of carbon dioxide and methane, and project these releases over three decades, given a continuation of current trends and policies. We then compare this Reference Case with three alternative scenarios, assuming successively more aggressive efforts to reduce greenhouse gas emissions through strategic implementation of energy efficiency and biomass resources. Finally, we identify and examine policy options for expanding the role of biomass in the region's energy and greenhouse gas mitigation strategies.

  18. Anaerobic bioassay of methane potential of microalgal biomass

    Science.gov (United States)

    Yen, Hong-Wei

    This study was undertaken to investigate the feasibility of using anaerobic digestion as a technique to recover solar energy embodied in excess algal biomass production harvested from Clemson University's high rate algal based Partitioned Aquaculture System (PAS) as an energy source to support PAS operations. In this study, four different organic substrates were loaded to anaerobic digesters in eight experimental trials, to ascertain the optimal combination of operational variables and effect of algal, or modified algal substrate upon methane production rate. The four substrates used in this study were: (1) a synthetic feedstock consisting of molasses and dog food, (2) a commercially obtained, readily degradable algal biomass (Spirulina ) in dry form, (3) PAS harvested and dewatered algal sludge, and (4) algal biomass blended with shredded waste paper or molasses as a carbon supplement for the adjustment of algal C/N ratio. Eight experimental trials using combinations of the four substrates were conducted in 15 liter digesters to investigate the effects of controlled digester parameters upon digester performance. Digesters operating at 20 days HRT, mesophilic digestion (35°C), and twice per day mixing at maximal loading rates produced maximal methane gas using PAS algal sludge. However, under these conditions overall methane production was less than 1000 ml CH4/l day. This low level of energy recovery from the fermentation of algal biomass (alone) is not energetically or economically favorable. Co-digestion of algal sludge and waste paper was investigated as a way to increase methane production. The data obtained from these trials suggest an optimum C/N ratio for co-digestion of algal sludge and waste paper in the range of 20--25/l. A balanced C/N ratio along with the stimulated increase in cellulase activity is suggested as likely reasons for increased methane production seen in co-digestion of algal sludge and waste paper. Yeast extract addition to anaerobic

  19. Co-inhibition of methanogens for methane mitigation in biodegradable wastes

    Institute of Scientific and Technical Information of China (English)

    ZHAO Tiantao; ZHANG Lijie; CHEN Haoquan; ZHAO Youcai

    2009-01-01

    The inhibition effects and mechanisms of chlorinated methane and acetylene on methanogenesis in the anaerobic digestion process of the biodegradable wastes were investigated.It was found that both chloroform and acetylene could effectively inhibit methanogens while the biodegradability of the wastes was not affected.Acetylene inhibited the activity of methanogens,while chloroform inhibited metabolic process of methanogenesis.A central composite design (CCD) and response surface regression analysis (RSREG) were employed to determine the optimum conditions and interaction effects of chloroform and acetylene in terms of inhibition efficiency,production of volatile fatty acids and molar ratio of propionic acid to acetic acid.Chloroform had significant effect on enhancing the production of VFA (F = 121.3;p0.05).In addition,a maximum molar ratio of propionic acid to acetic acid of 1.208 was estimated under the optimum conditions of chloroform concentration of 9.05 mg/kg and acetylene concentration of 3.6×10-3 (V/V).Hence,methanogens in the wastes can be inhibited while the stabilization process of the biodegradable wastes can still work well,as propionic acid generated during the inhibition process could hardly be utilized by methanogens.

  20. Rainwater harvesting potentials for drought mitigation in Iran.

    Science.gov (United States)

    Tabatabaee, J; Han, M Y

    2010-01-01

    In order to evaluate the potential of rainwater harvesting (RWH) for mitigating water scarcity in a semi-arid zone of the country (Mashhad-Iran), three typical RWH systems were installed and monitored. The first system consists of 5,000 m² natural ground catchment which was leveled and covered with plastic sheets allowing for maximum possible runoff generation. Surface runoff was conducted into a 500 m³ ground reservoir via a series of draining ditches and an end collection channel. The water collected from a plastic covered catchment was used for irrigation of dryland wheat cultivation. According to the result of two years measurements, grain yield was almost doubled in irrigated plots when compared to conventional rainfed cultivation. In the second RWH system, runoff generated from about 2 ha asphaltic road and parking was diverted into a 1,200 m³ ground reservoir. The results of 2 years measurement for reservoir inflow and outflow indicated that runoff generated during rainy season was sufficient to produce necessary water for irrigating 900 planted fruit trees during successive dry seasons. The last experiment reported here is about a 40 m² roof area which was connected to a plastic tank for runoff measurement. The conclusion was that the proposed RWH system can produce enough water for building's toilets' flashes and other sanitary purposes so that the potable water could be saved considerably. In general, the results of three rainwater harvesting experiments showed the importance of using rainwater for compensating the effect of water shortages which is repeatedly occurring due to the effect of current climate change and ever increasing water utilization for drinking and food production.

  1. Global Change Simulations Affect Potential Methane Oxidation in Upland Soils

    Science.gov (United States)

    Blankinship, J. C.; Hungate, B. A.

    2004-12-01

    Atmospheric concentrations of methane (CH4) are higher now than they have ever been during the past 420,000 years. However, concentrations have remained stable since 1999. Emissions associated with livestock husbandry are unlikely to have changed, so some combination of reduced production in wetlands, more efficient capture by landfills, or increased consumption by biological CH4 oxidation in upland soils may be responsible. Methane oxidizing bacteria are ubiquitous in upland soils and little is known about how these bacteria respond to anthropogenic global change, and how they will influence - or already are influencing - the radiative balance of the atmosphere. Might ongoing and future global changes increase biological CH4 oxidation? Soils were sampled from two field experiments to assess changes in rates of CH4 oxidation in response to global change simulations. Potential activities of CH4 oxidizing bacterial communities were measured through laboratory incubations under optimal temperature, soil moisture, and atmospheric CH4 concentrations (~18 ppm, or 10x ambient). The ongoing 6-year multifactorial Jasper Ridge Global Change Experiment (JRGCE) simulates warming, elevated precipitation, elevated atmospheric CO2, elevated atmospheric N deposition, and increased wildfire frequency in an annual grassland in a Mediterranean-type climate in central California. The ongoing 1-year multifactorial Merriam Climate Change Experiment (MCCE) simulates warming, elevated precipitation, and reduced precipitation in four different types of ecosystems along an elevational gradient in a semi-arid climate in northern Arizona. The high desert grassland, pinyon-juniper woodland, ponderosa pine forest, and mixed conifer forest ecosystems range in annual precipitation from 100 to 1000 mm yr-1, and from productivity being strongly water limited to strongly temperature limited. Among JRGCE soils, elevated atmospheric CO2 increased potential CH4 oxidation rates (p=0.052) and wildfire

  2. Mitigation of methane emissions in a pilot-scale biocover system at the AV Miljø Landfill, Denmark: 1. System design and gas distribution

    DEFF Research Database (Denmark)

    Cassini, Filippo; Scheutz, Charlotte; Skov, Bent Henning

    2017-01-01

    Greenhouse gas mitigation at landfills by methane oxidation in engineered biocover systems is believed to be a cost effective technology, but so far a full quantitative evaluation of the efficiency of the technology in full scale has only been carried out in a few cases. A third generation semi......-passive biocover system was constructed at the AV Miljø Landfill, Denmark. The biocover system was fed by landfill gas pumped out of three leachate collection wells. An innovative gas distribution system was used to overcome the commonly observed surface emission hot spot areas resulting from an uGreenhouse gas...... mitigation at landfills by methane oxidation in engineered biocover systems is believed to be a cost effective technology, but so far a full quantitative evaluation of the efficiency of the technology in full scale has only been carried out in a few cases. A third generation semi-passive biocover system...

  3. Molecular Weight, Protein Binding Affinity and Methane Mitigation of Condensed Tannins from Mangosteen-peel (Garcinia mangostana L).

    Science.gov (United States)

    Paengkoum, P; Phonmun, T; Liang, J B; Huang, X D; Tan, H Y; Jahromi, M F

    2015-10-01

    The objectives of this study were to determine the molecular weight of condensed tannins (CT) extracted from mangosteen (Garcinia mangostana L) peel, its protein binding affinity and effects on fermentation parameters including total gas, methane (CH4) and volatile fatty acids (VFA) production. The average molecular weight (Mw) of the purified CT was 2,081 Da with a protein binding affinity of 0.69 (the amount needed to bind half the maximum bovine serum albumin). In vitro gas production declined by 0.409, 0.121, and 0.311, respectively, while CH4 production decreased by 0.211, 0.353, and 0.549, respectively, with addition of 10, 20, and 30 mg CT/500 mg dry matter (DM) compared to the control (pmangosteen-peel on in vitro DM degradability (IVDMD) and in vitro N degradability was negative and linear (pmangosteen-peel is lower than those reported for Leucaena forages, however, the former has stronger negative effect on IVDMD. Therefore, the use of mangosteen-peel as protein source and CH4 mitigating agent in ruminant feed requires further investigations.

  4. Additive methane-mitigating effect between linseed oil and nitrate fed to cattle.

    Science.gov (United States)

    Guyader, J; Eugène, M; Meunier, B; Doreau, M; Morgavi, D P; Silberberg, M; Rochette, Y; Gerard, C; Loncke, C; Martin, C

    2015-07-01

    The objective of this study was to test the effect of linseed oil and nitrate fed alone or in combination on methane (CH4) emissions and diet digestibility in cows. The experiment was conducted as a 2 × 2 factorial design using 4 multiparous nonlactating Holstein cows (initial BW 656 ± 31 kg). Each experimental period lasted 5 wk, with measures performed in the final 3 wk (wk 3 to 5). Diets given on a DM basis were 1) control (CON; 50% natural grassland hay and 50% concentrate), 2) CON with 4% linseed oil (LIN), 3) CON with 3% calcium nitrate (NIT), and 4) CON with 4% linseed oil plus 3% calcium nitrate (LIN+NIT). Diets were offered twice daily and were formulated to deliver similar amounts (DM basis) of CP (12.2%), starch (25.5%), and NDF (39.5%). Feed offer was restricted to 90% of voluntary intake (12.4 kg DMI/d). Total tract digestibility and N balance were determined from total feces and urine collected separately for 6 d during wk 4. Daily CH4 emissions were quantified using open chambers for 4 d during wk 5. Rumen fermentation and microbial parameters were analyzed from samples taken before and 3 h after the morning feeding. Rumen concentrations of dissolved hydrogen (H2) were measured continuously up to 6 h after feeding using a H2 sensor. Compared with the CON diet linseed oil and nitrate decreased (P linseed plus nitrate also increased H2 concentrations in the rumen. Diets had no effect (P > 0.05) on total tract digestibility of nutrients, except linseed oil, which tended to reduce (P linseed oil. This study demonstrates an additive effect between nitrate and linseed oil for reducing methanogenesis in cows without altering diet digestibility.

  5. Assessing the resources and mitigation potential of European forests

    Science.gov (United States)

    Hasenauer, Hubert; Neumann, Mathias; Moreno, Adam; Running, Steve

    2017-04-01

    Today 40 % of the European land area is covered with forests managed for the provision of ecosystem services including timber production. Forests store large amounts of carbon and are the main resource for the growing demand of a bio-based economy. They are also a major source for biodiversity. Thus a consistent pan-European gridded data set on the state of forest resources is essential for researchers, policy makers and conservationists to study and understand the European forests for the global carbon cycle independent of political boundaries. The purpose of this study is to use existing European data to develop a consistent pan-European data set for Net Primary Production (NPP), live tree carbon per hectare, volume per hectare, mean tree height and mean tree age by integrating remotely sensed satellite data and harmonized NFI data from 13 different European countries. We provide new NPP estimates using the MOD17 algorithm by collating a newly down-scaled daily climate dataset across Europe. By consolidating these two independent productivity data sources (top down satellite versus bottom up terrestrial forest NFI data) for assessing forest resources in Europe, we are able to detect and quantify forest management impacts. We produce a pan-European map for each of the five key variables on a 0.133° grid representing the time period 2000-2010. The results show distinct differences in the carbon storage of European forests due to biophysical limits and regional historic drivers in forest management, which directly affect the carbon mitigation option of European forests. We use this data to assess the state of forest resources across Europe showing that mountainous regions have the highest carbon and volume per hectare values, central Europe has the tallest mean tree heights and Austria and Northern Scandinavia have the oldest mean tree ages. Cross-validation of the data indicates that the error varies by forest characteristic but shows negligible biases for all. We

  6. Methane emission from ruminants and solid waste: A critical analysis of baseline and mitigation projections for climate and policy studies

    Science.gov (United States)

    Matthews, E.

    2012-12-01

    Current and projected estimates of methane (CH4) emission from anthropogenic sources are numerous but largely unexamined or compared. Presented here is a critical appraisal of CH4 projections used in climate-chemistry and policy studies. We compare emissions for major CH4 sources from several groups, including our own new data and RCP projections developed for climate-chemistry models for the next IPCC Assessment Report (AR5). We focus on current and projected baseline and mitigation emissions from ruminant animals and solid waste that are both predicted to rise dramatically in coming decades, driven primarily by developing countries. For waste, drivers include increasing urban populations, higher per capita waste generation due to economic growth and increasing landfilling rates. Analysis of a new global data base detailing waste composition, collection and disposal indicates that IPCC-based methodologies and default data overestimate CH4 emission for the current period which cascades into substantial overestimates in future projections. CH4 emission from solid waste is estimated to be ~10-15 Tg CH4/yr currently rather than the ~35 Tg/yr often reported in the literature. Moreover, emissions from developing countries are unlikely to rise rapidly in coming decades because new management approaches, such as sanitary landfills, that would increase emissions are maladapted to infrastructures in these countries and therefore unlikely to be implemented. The low current emission associated with solid waste (~10 Tg), together with future modest growth, implies that mitigation of waste-related CH4 emission is a poor candidate for slowing global warming. In the case of ruminant animals (~90 Tg CH4/yr currently), the dominant assumption driving future trajectories of CH4 emission is a substantial increase in meat and dairy consumption in developing countries to be satisfied by growing animal populations. Unlike solid waste, current ruminant emissions among studies exhibit a

  7. Anycast and its potential for DDoS mitigation

    NARCIS (Netherlands)

    de Vries, Wouter Bastiaan; de Oliveira Schmidt, R.; Pras, Aiko

    IP anycast is widely being used to distribute essential Internet services, such as DNS, across the globe. One of the main reasons for doing so is to increase the redundancy of the service and reduce the impacts of the growing threat of DDoS attacks. IP anycast can be further used to mitigate DDoS

  8. The future of methane

    Energy Technology Data Exchange (ETDEWEB)

    Howell, D.G.

    1995-12-31

    Natural gas, mainly methane, produces lower CO{sub 2}, CO, NO{sub x}, SO{sub 2} and particulate emissions than either oil or coal; thus further substitutions of methane for these fuels could help mitigate air pollution. Methane is, however, a potent greenhouse gas and the domestication of ruminants, cultivation of rice, mining of coal, drilling for oil, and transportation of natural gas have all contributed to a doubling of the amount of atmospheric methane since 1800. Today nearly 300,000 wells yearly produce ca. 21 trillion cubic feet of methane. Known reserves suggest about a 10 year supply at the above rates of recovery; and the potential for undiscovered resources is obscured by uncertainty involving price, new technologies, and environmental restrictions steming from the need to drill an enormous number of wells, many in ecologically sensitive areas. Until all these aspects of methane are better understood, its future role in the world`s energy mix will remain uncertain. The atomic simplicity of methane, composed of one carbon and four hydrogen atoms, may mask the complexity and importance of this, the most basic of organic molecules. Within the Earth, methane is produced through thermochemical alteration of organic materials, and by biochemical reactions mediated by metabolic processes of archaebacteria; some methane may even be primordial, a residue of planetary accretion. Methane also occurs in smaller volumes in landfills, rice paddies, termite complexes, ruminants, and even many humans. As an energy source, its full energy potential is controversial. Methane is touted by some as a viable bridge to future energy systems, fueled by the sun and uranium and carried by electricity and hydrogen.

  9. Biochemical methane potential (BMP) of solid organic materials

    DEFF Research Database (Denmark)

    Raposo, Francisco; Fernández-Cegrí, V.; De la Rubia, M.A.

    2010-01-01

    and experimental conditions were reported. The study was performed using 4 samples: 3 reference substrates (starch, cellulose and gelatine), and 1 raw material (mung bean). The BMP of mung bean was carried out at two inoculum to substrate ratios (ISR), specifically 2 and 1. The methane yields of reference......L CH4/g VSadded and 86±8%, respectively. In addition, the anaerobic digestion of the raw material elected did not show influence on the ISR in the extent of the biotransformation....

  10. Application of Aqueous Ammonia Soaking for enhancement of methane potential of swine manure fibers

    DEFF Research Database (Denmark)

    Jurado, Esperanza; Gavala, Hariklia N.; Skiadas, Ioannis

    2012-01-01

    of the solid fraction is a prerequisite for increasing its digestibility. The purpose of the present study was to evaluate aqueous ammonia soaking (AAS) and subsequent ammonia removal as a pretreatment method for increasing methane potential and biogas productivity of raw and digested manure fibers. Methods......Purpose: Increasing the methane productivity of manure based biogas plants is challenging because the solid fraction of manure contains lignocellulosic fibers, which are difficult to biodegrade and thus make anaerobic digestion process slow and economically unfavourable. Therefore, pretreatment......: Manure fibers were pretreated with AAS for 3 days at 22°C and methane production was evaluated in batch experiments (methane potential tests). Results: It was proven that AAS altered the lignocellulosic structure increasing significantly the concentration of soluble organic material. AAS pretreatment...

  11. GHG emissions and mitigation potential in organic egg production

    Science.gov (United States)

    Vetter, Sylvia; Malin, Daniella; Smith, Pete; Hillier, Jon

    2016-04-01

    Models and tools are used to estimate greenhouse gas (GHG) emissions in agriculture from management processes when measurements are not available. The Cool Farm Tool is widely used by farmers for this purpose. This study focus on the livestock part of the tool. The GHG emissions from livestock include enteric methane emissions from ruminants, nitrous oxide emissions from manure management, land use and land-use change, feed production, processing and transport. A case study is presented of organic egg producers in the USA, who used the tool over three years to calculate their emissions with the Cool Farm Tool. The highest GHG emissions were produced through feed, followed by transport and manure management. The farmers became more aware about the emissions in egg production and started to take action to reduce emissions. The results showed that the averaged GHG emissions decreased over the three years of the study.

  12. Snowmelt runoff modeling: Limitations and potential for mitigating water disputes

    Science.gov (United States)

    Kult, Jonathan; Choi, Woonsup; Keuser, Anke

    2012-04-01

    SummaryConceptual snowmelt runoff models have proven useful for estimating discharge from remote mountain basins including those spanning the various ranges of the Himalaya. Such models can provide water resource managers with fairly accurate predictions of water availability for operational purposes (e.g. irrigation and hydropower). However, these models have limited ability to address characteristic components of water disputes such as diversions, storage and withholding. Contemporary disputes between India and Pakistan surrounding the snowmelt-derived water resources of the Upper Indus Basin highlight the need for improved water balance accounting methods. We present a research agenda focused on providing refined hydrological contributions to water dispute mitigation efforts.

  13. Intermolecular interaction potentials of methane-argon complex calculated using LDA approaches

    Institute of Scientific and Technical Information of China (English)

    Bai Yu-Lin; Chen Xiang-Rong; Zhou Xiao-Lin; Yang Xiang-Dong; Wang Hai-Yan

    2004-01-01

    The intermolecular interaction potential for methane-argon complex is calculated by local density approximation (LDA) approaches. The calculated potential has a minimum when the intermolecular distance of methane-argon complex is 6.75 a.u.; the corresponding depth of the potential is 0.0163eV which has good agreement with experimental data. We also have made a nonlinear fitting of our results for the Lennard-Jones (12-6) potential function and obtain that V(R) = 143794365.332/R12 - 3032.093/R6 (R in a.u. and V(R) in eV).

  14. Methane mitigation in transplanting and direct-wet seeding rice fields treated with fertilizers under condition of alternately flooding and soil aerating

    Directory of Open Access Journals (Sweden)

    Sanwangsi, M.

    2006-05-01

    Full Text Available Rice is main staple crop of the world. Growing rice in flooded water entails methane (CH4 emission. CH4 is one of greenhouse gases contributing to global warming. The experiment aimed to clarify the influence of fertilizer and water management on total methane emission (TME, methane mitigation and rice yields (RY. The experimental design was a split - split plot with 3 replications taking 2 cultivation in main plots, transplanting (TP rice and direct-wet seeding (DWS rice fields; 2 basal fertilizers, 16-16-8, 20 kg/rai and chicken manure pallet (CMP, 105 kg/rai in sub plots; and 3 top dressing fertilizers 1 none, 2 urea (46% N, 15 kg/rai and 3 ammonium sulfate (AS, 21% N, 30 kg/rai in sub-sub plots. It also examined relationship between quantity of paddy-soil water, TME and RY of both cultivations. Methane emission rate (MER occurred during the whole growth period and was characterized by 2 large peaks: one from after transplanting or broadcasting to maximum tillering stage and the other from flowering to yellow ripening stage. Rapid declines of MER were dictated by soil aeration recognized as 3-5 days cracks. In TP rice plot based with CMP, 105 kg/rai, topped with AS, 30 kg/rai, TME decreased to 73.0% and RY increased to 14.7% over that of untreated plots with top dressing fertilizer, while in that topped with urea, 15 kg/rai, TME decreased to 68.9% and RY increased to 16.9%. In all of DWS rice plots which were topped with AS or urea, declines of TME ranged from 27.3 to 56.4% and increase of RY ranged from 31.3 to 47.9% over those without top dressing. In both TP and DWS plots, TMEs were closely correlated with the quantity of paddy-soil water (r = 0.83 and 0.86, respectively and with submergence days (r = 0.94 and 0.89, respectively. Hence, saturated condition in paddy soil is a primary factor for methanogenesis. Moreover, for TP rice, the relationship between TME and RY was weakly positive (r = 0.16, whereas that for DWS rice was obviously

  15. The potential contribution to climate change mitigation from temporary carbon storage in biomaterials

    DEFF Research Database (Denmark)

    Jørgensen, Susanne Vedel; Hauschild, Michael Zwicky; Nielsen, Per H.

    2015-01-01

    contributes with negative CTP values, which means mitigation. The longer the duration of the storage, the larger the mitigation potential.Temporary carbon storage in biomaterials has a potential for contributing to avoid or postpone the crossing of a climatic target level of 450 ppm CO2e, depending on GHG...... concentration development scenario. The potential mitigation value depends on the timing of sequestration and re-emission of CO2. The suggested CTP approach enables inclusion of the potential benefit from temporary carbon storage in the environmental profile of biomaterials. This should be seen as supplement...... value of temporary carbon storage in terms of climate change mitigation has been widely discussed, this has not yet been directly coupled to avoiding climatic target levels representing predicted climatic tipping points. This paper provides recommendations on how to model temporary carbon storage...

  16. phMRI: methodological considerations for mitigating potential confounding factors

    Directory of Open Access Journals (Sweden)

    Julius H Bourke

    2015-05-01

    Full Text Available Pharmacological Magnetic Resonance Imaging (phMRI is a variant of conventional MRI that adds pharmacological manipulations in order to study the effects of drugs, or uses pharmacological probes to investigate basic or applied (e.g. clinical neuroscience questions. Issues that may confound the interpretation of results from various types of phMRI studies are briefly discussed, and a set of methodological strategies that can mitigate these problems are described. These include strategies that can be employed at every stage of investigation, from study design to interpretation of resulting data, and additional techniques suited for use with clinical populations are also featured. Pharmacological MRI is a challenging area of research that has both significant advantages and formidable difficulties, however with due consideration and use of these strategies many of the key obstacles can be overcome.

  17. Functional traits of urban trees: Air pollution mitigation potential

    DEFF Research Database (Denmark)

    Grote, Rüdiger; Samson, Roeland; Alonso, Rocío

    2016-01-01

    In an increasingly urbanized world, air pollution mitigation is considered one of most important issues in city planning. Urban trees help to improve air quality by facilitating widespread deposition of various gases and particles through the provision of large surface areas as well as through...... are manifested depends on species-specific tree properties: that is, their "traits". We summarize and discuss the current knowledge on how such traits affect urban air pollution. We also present aggregated traits of some of the most common tree species in Europe, which can be used as a decision-support tool...... their influence on microclimate and air turbulence. However, many of these trees produce wind-dispersed pollen (a known allergen) and emit a range of gaseous substances that take part in photochemical reactions - all of which can negatively affect air quality. The degree to which these air-quality impacts...

  18. Incentives for Methane Mitigation and Energy-Efficiency Improvements in Case of Ukraine’s Natural Gas Transmission System

    Energy Technology Data Exchange (ETDEWEB)

    Roshchanka, Volha; Evans, Meredydd

    2014-06-01

    Reducing methane losses is a concern for climate change policy and energy policy. The energy sector is the major source of methane emissions into the atmosphere. Reducing methane emissions and avoiding combustion can be very cost-effective, but various barriers prevent such energy-efficiency measures from taking place. To date, few examples of industry-wide improvements exist. One example of substantial investments into upgrading natural gas transmission system comes from Ukraine. The Ukrainian transmission company, Ukrtransgaz, reduced its own system’s natural gas consumption by 68 percent in 2011 compared to the level in 2005. Evaluating reductions in methane emissions is challenging because of lack of accurate data and gaps in accounting methodologies. At the same time, Ukraine’s transmission system has undergone improvements that, at the very least, have contained methane emissions, if not substantially reduced them. In this paper, we describe recent developments in Ukraine’s natural gas transmission system and analyze the incentives that forced the sector to pay close attention to its methane losses. Ukraine is one of most energy-intensive countries, among the largest natural gas consumers in the world, and a significant emitter of methane. The country is also dependent on imports of natural gas. A combination of steep increases in the price of imported natural gas, and comprehensive domestic environmental and energy policies, regional integration policy, and international environmental agreements has created conditions for successful methane emission and combustion reductions. Learning about such case studies can help us design better policies elsewhere.

  19. Biochemical methane potential (BMP) of agro-food wastes from the Cider Region (Spain).

    Science.gov (United States)

    Nieto, P P; Hidalgo, D; Irusta, R; Kraut, D

    2012-01-01

    An inventory of agro-food industry organic waste streams with a high potential for biogas transformation was studied in a logistically viable area (Cider Region, Asturias, Spain). Three industries were selected as the most viable ones: livestock, dairy and beverage. The potential for methane production from six wastes (beverage waste, BW; milled apple waste, MA; milk waste, MK; yogurt waste, YG; fats and oils from dairy wastewater treatment, F&O and cattle manure, CM) at five different substrate:inoculum ratios (0.25, 0.50, 0.75, 1.00 and 1.50) was evaluated in laboratory batch assays. Obtained methane yields ranged from 202-549 mL STP CH(4)·g VS waste(-1), and the methane content in biogas ranged from 58-76%. The ultimate practical biochemical methane potentials were slightly affected by the substrate:inoculum ratio. The estimation of the regional fluxes of waste and methane potentials suggests anaerobic digestion as a sustainable solution for the valorization of the organic wastes generated in this Region.

  20. Comparison of methane production potential, biodegradability, and kinetics of different organic substrates.

    Science.gov (United States)

    Li, Yeqing; Zhang, Ruihong; Liu, Guangqing; Chen, Chang; He, Yanfeng; Liu, Xiaoying

    2013-12-01

    The methane production potential, biodegradability, and kinetics of a wide range of organic substrates were determined using a unified and simple method. Results showed that feedstocks that contained high energy density and easily degradable substrates exhibited high methane production potential and biodegradability. Lignocellulosic biomass with high content of fibrous compositions had low methane yield and biodegradability. Feedstocks with high lignin content (≥ 15%, on a TS basis) had low first-order rate constant (0.05-0.06 1/d) compared to others. A negative linear correlation between lignin content and experimental methane yield (or biodegradability) was found for lignocellulosic and manure wastes. This could be used as a fast method to predict the methane production potential and biodegradability of fiber-rich substrates. The findings of this study provided a database for the conversion efficiency of different organic substrates and might be useful for applications of biomethane potential assay and anaerobic digestion in the future. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Reactive nitrogen requirements to feed the world in 2050 and potential to mitigate nitrogen pollution

    Science.gov (United States)

    Bodirsky, Benjamin Leon; Popp, Alexander; Lotze-Campen, Hermann; Dietrich, Jan Philipp; Rolinski, Susanne; Weindl, Isabelle; Schmitz, Christoph; Müller, Christoph; Bonsch, Markus; Humpenöder, Florian; Biewald, Anne; Stevanovic, Miodrag

    2014-05-01

    Reactive nitrogen (Nr) is an indispensable nutrient for agricultural production and human alimentation. Simultaneously, agriculture is the largest contributor to Nr pollution, causing severe damages to human health and ecosystem services. The trade-off between food availability and Nr pollution can be attenuated by several key mitigation options, including Nr efficiency improvements in crop and animal production systems, food waste reduction in households and lower consumption of Nr-intensive animal products. However, their quantitative mitigation potential remains unclear, especially under the added pressure of population growth and changes in food consumption. Here we show by model simulations, that under baseline conditions, Nr pollution in 2050 can be expected to rise to 102-156% of the 2010 value. Only under ambitious mitigation, does pollution possibly decrease to 36-76% of the 2010 value. Air, water and atmospheric Nr pollution go far beyond critical environmental thresholds without mitigation actions. Even under ambitious mitigation, the risk remains that thresholds are exceeded.

  2. Potential for methane production from typical Mediterranean agro-industrial by-products

    Energy Technology Data Exchange (ETDEWEB)

    Fountoulakis, M.S.; Drakopoulou, S.; Terzakis, S.; Georgaki, E.; Manios, T. [Laboratory of Solid Waste and Wastewater Management, School of Agricultural Technology, Technological Educational Institute of Crete, GR-71004 Iraklio, Crete (Greece)

    2008-02-15

    This work examines the potential for methane production from anaerobic co-digestion of olive mill wastewater and wine-grape residues with slaughterhouse wastewater. Continuous (mesophilic) and batch (mesophilic and thermophilic) experiments were studied, both with the separate types of by-products and with mixtures. Methane yields from olive oil wastewater, winery residues and slaughterhouse wastewater were 108, 147 and 297 L CH{sub 4} kg{sup -1} COD fed respectively. Co-digestion with 50% olive oil wastewater and 50% slaughterhouse wastewater or 50% winery residues gave a methane yield of 184 and 214 L CH{sub 4} kg{sup -1} COD, respectively. Furthermore, the methane yield was 188 L CH{sub 4} kg{sup -1} COD added, co-digesting a mixture of 50% winery residues and slaughterhouse wastewater. Finally, the same mixtures under thermophilic conditions gave methane yields of 282, 301 and 219 L CH{sub 4} kg{sup -1} COD, respectively. These results suggest that methane can be produced very efficiently by co-digesting olive oil wastewater, wine-grape residues and slaughterhouse wastewater. (author)

  3. Methane production potentials, pathways, and communities of methanogens in vertical sediment profiles of river Sitka.

    Science.gov (United States)

    Mach, Václav; Blaser, Martin B; Claus, Peter; Chaudhary, Prem P; Rulík, Martin

    2015-01-01

    Biological methanogenesis is linked to permanent water logged systems, e.g., rice field soils or lake sediments. In these systems the methanogenic community as well as the pathway of methane formation are well-described. By contrast, the methanogenic potential of river sediments is so far not well-investigated. Therefore, we analyzed (a) the methanogenic potential (incubation experiments), (b) the pathway of methane production (stable carbon isotopes and inhibitor studies), and (c) the methanogenic community composition (terminal restriction length polymorphism of mcrA) in depth profiles of sediment cores of River Sitka, Czech Republic. We found two depth-related distinct maxima for the methanogenic potentials (a) The pathway of methane production was dominated by hydrogenotrophic methanogenesis (b) The methanogenic community composition was similar in all depth layers (c) The main TRFs were representative for Methanosarcina, Methanosaeta, Methanobacterium, and Methanomicrobium species. The isotopic signals of acetate indicated a relative high contribution of chemolithotrophic acetogenesis to the acetate pool.

  4. Incentives for methane mitigation and energy-efficiency improvements in the case of Ukraine's natural gas transmission system

    Science.gov (United States)

    Roshchanka, Volha; Evans, Meredydd

    2014-06-01

    Reducing methane losses is a concern for climate change policy and energy policy. The energy sector is the major source of anthropogenic methane emissions into the atmosphere in Ukraine. Reducing methane emissions and avoiding combustion can be very cost-effective, but various barriers prevent such energy-efficiency measures from taking place. To date, few examples of industry-wide improvements exist. One example of substantial investments into upgrading natural gas transmission system comes from Ukraine's natural gas transmission company, Ukrtransgaz. The company's investments into system upgrades, along with a 34% fall in throughput, resulted in reduction of Ukrtransgaz system's own consumption of natural gas by 68% in 2011 compared to the level in 2005. Evaluating reductions in methane emissions is challenging because of lack of accurate data and gaps in accounting methodologies. At the same time, Ukraine's transmission system has undergone improvements that, at the very least, have contained methane emissions, if not substantially reduced them. In this paper, we describe recent developments in Ukraine's natural gas transmission system and analyze the incentives that forced the sector to pay close attention to its methane losses. Ukraine is one of the most energy-intensive countries, among the largest natural gas consumers in the world, and a significant emitter of methane. The country is also dependent on imports of natural gas. A combination of several factors has created conditions for successful reductions in methane emissions and combustion. These factors include: an eightfold increase in the price of imported natural gas; comprehensive domestic environmental and energy policies, such as the Laws of Ukraine on Protecting the Natural Environment and on Air Protection; policies aimed at integration with European Union's energy market and accession to the Energy Community Treaty; and the country's participation in international cooperation on environment, such

  5. [Experimental study on methane potentials of source-separated BMW and individual waste materials].

    Science.gov (United States)

    Feng, Lei; Li, Run-dong; Li, Yan-ji; Ke, Xin; Wei, Li-hong; Luo, Xiao-song

    2008-08-01

    A laboratory procedure is described for measuring methane potentials of source-separated bio-organic municipal waste (BMW). Triplicate reactors with about 20 grams fresh material were incubated at 37 degrees C with 300 mL inoculum from Shenyang wastewater treatment plant and the methane production was followed over a 50 d period by regular measurement of methane on a gas chromatograph. At 37 degrees C, the methane production efficiency of source-separated BMW and individual waste materials was: starch > BMW > protein > food oil > fat > paper. For the source-separated BMW,starch,protein,food oil,fat and paper, the methane potential (CH4/VS) of 218.15, 209.11, 194.20, 238.86, 257.82 and 131.41 mL/g were found,and ultimate biodegradability of 6 difference materials were 67.73%, 72.88%, 65.84%, 78.38%, 74.11% and 47.98%, respectively.

  6. Did state renewable portfolio standards induce technical change in methane mitigation in the U.S. landfill sector?

    Science.gov (United States)

    Delhotal, Katherine Casey

    Landfill gas (LFG) projects use the gas created from decomposing waste, which is approximately 49% methane, and substitute it for natural gas in engines, boilers, turbines, and other technologies to produce energy or heat. The projects are beneficial in terms of increased safety at the landfill, production of a cost-effective source of energy or heat, reduced odor, reduced air pollution emissions, and reduced greenhouse gas emissions. However, landfills sometimes face conflicting policy incentives. The theory of technical change shows that the diffusion of a technology or groups of technologies increases slowly in the beginning and then picks up speed as knowledge and better understanding of using the technology diffuses among potential users. Using duration analysis, data on energy prices, State and Federal policies related to landfill gas, renewable energy, and air pollution, as well as control data on landfill characteristics, I estimate the influence and direction of influence of renewable portfolio standards (RPS). The analysis found that RPS positively influences the diffusion of landfill gas technologies, encouraging landfills to consider electricity generation projects over direct sales of LFG to another facility. Energy price increases or increased revenues for a project are also critical. Barriers to diffusion include air emission permits in non-attainment areas and policies, such as net metering, which promote other renewables over LFG projects. Using the estimates from the diffusion equations, I analyze the potential influence of a Federal RPS as well as the potential interaction with a Federal, market based climate change policy, which will increase the revenue of a project through higher energy sale prices. My analysis shows that a market based climate change policy such as a cap-and-trade or carbon tax scheme would increase the number of landfill gas projects significantly more than a Federal RPS.

  7. Modelled isotopic fractionation and transient diffusive release of methane from potential subsurface sources on Mars

    Science.gov (United States)

    Stevens, Adam H.; Patel, Manish R.; Lewis, Stephen R.

    2017-01-01

    We calculate transport timescales of martian methane and investigate the effect of potential release mechanisms into the atmosphere using a numerical model that includes both Fickian and Knudsen diffusion. The incorporation of Knudsen diffusion, which improves on a Fickian description of transport given the low permeability of the martian regolith, means that transport timescales from sources collocated with a putative martian water table are very long, up to several million martian years. Transport timescales also mean that any temporally varying source process, even in the shallow subsurface, would not result in a significant, observable variation in atmospheric methane concentration since changes resulting from small variations in flux would be rapidly obscured by atmospheric transport. This means that a short-lived 'plume' of methane, as detected by Mumma et al. (2009) and Webster et al. (2014), cannot be reconciled with diffusive transport from any reasonable depth and instead must invoke alternative processes such as fracturing or convective plumes. It is shown that transport through the martian regolith will cause a significant change in the isotopic composition of the gas, meaning that methane release from depth will produce an isotopic signature in the atmosphere that could be significantly different than the source composition. The deeper the source, the greater the change, and the change in methane composition in both δ13C and δD approaches -1000 ‰ for sources at a depth greater than around 1 km. This means that signatures of specific sources, in particular the methane produced by biogenesis that is generally depleted in 13CH4 and CH3D, could be obscured. We find that an abiogenic source of methane could therefore display an isotopic fractionation consistent with that expected for biogenic source processes if the source was at sufficient depth. The only unambiguous inference that can be made from measurements of methane isotopes alone is a measured

  8. Analysis of methane potentials of steam-exploded wheat straw and estimation of energy yields of combined ethanol and methane production.

    Science.gov (United States)

    Bauer, Alexander; Bösch, Peter; Friedl, Anton; Amon, Thomas

    2009-06-01

    Agrarian biomass as a renewable energy source can contribute to a considerable CO(2) reduction. The overriding goal of the European Union is to cut energy consumption related greenhouse gas emission in the EU by 20% until the year 2020. This publication aims at optimising the methane production from steam-exploded wheat straw and presents a theoretical estimation of the ethanol and methane potential of straw. For this purpose, wheat straw was pretreated by steam explosion using different time/temperature combinations. Specific methane yields were analyzed according to VDI 4630. Pretreatment of wheat straw by steam explosion significantly increased the methane yield from anaerobic digestion by up to 20% or a maximum of 331 l(N)kg(-1) VS compared to untreated wheat straw. Furthermore, the residual anaerobic digestion potential of methane after ethanol fermentation was determined by enzymatic hydrolysis of pretreated wheat straw using cellulase. Based on the resulting glucose concentration the ethanol yield and the residual sugar available for methane production were calculated. The theoretical maximum ethanol yield of wheat straw was estimated to be 0.249 kg kg(-1) dry matter. The achievable maximum ethanol yield per kg wheat straw dry matter pretreated by steam explosion and enzymatic hydrolysis was estimated to be 0.200 kg under pretreatment conditions of 200 degrees C and 10 min corresponding to 80% of the theoretical maximum. The residual methane yield from straw stillage was estimated to be 183 l(N)kg(-1) wheat straw dry matter. Based on the presented experimental data, a concept is proposed that processes wheat straw for ethanol and methane production. The concept of an energy supply system that provides more than two forms of energy is met by (1) upgrading obtained ethanol to fuel-grade quality and providing methane to CHP plants for the production of (2) electric energy and (3) utility steam that in turn can be used to operate distillation columns in the

  9. Quantifying the biophysical climate change mitigation potential of Canada's forest sector

    Directory of Open Access Journals (Sweden)

    C. E. Smyth

    2014-01-01

    Full Text Available The potential of forests and the forest sector to mitigate greenhouse gas (GHG emissions is widely recognized, but challenging to quantify at a national scale. Forests and their carbon (C sequestration potential are affected by management practices, where wood harvesting transfers C out of the forest into products, and subsequent regrowth allows further C sequestration. Here we determine the mitigation potential of the 2.3 × 106 km2 of Canada's managed forests from 2015 to 2050 using the Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3, a harvested wood products model that estimates emissions based on product half-life decay times, and an account of emission substitution benefits from the use of wood products and bioenergy. We examine several mitigation scenarios with different assumptions about forest management activity levels relative to a base-case scenario, including improved growth from silvicultural activities, increased harvest and residue management for bioenergy, and reduced harvest for conservation. We combine forest management options with two mitigation scenarios for harvested wood product use involving an increase in either long-lived products or bioenergy uses. Results demonstrate large differences among alternative scenarios, and we identify potential mitigation scenarios with increasing benefits to the atmosphere for many decades into the future, as well as scenarios with no net benefit over many decades. The greatest mitigation impact was achieved through a mix of strategies that varied across the country and had cumulative mitigation of 254 Tg CO2e in 2030, and 1180 Tg CO2e in 2050. We conclude that (i national-scale forest sector mitigation options need to be assessed rigorously from a systems perspective to avoid the development of policies that deliver no net benefits to the atmosphere, (ii a mix of strategies implemented across the country achieves the greatest mitigation impact, and (iii because of the time

  10. Potential of biogas and methane production from anaerobic digestion of poultry slaughterhouse effluent

    Directory of Open Access Journals (Sweden)

    Natália da Silva Sunada

    2012-11-01

    Full Text Available The objective of this study was to evaluate the efficiency of anaerobic digestion on the treatment of effluent from poultry slaughterhouse. The experiment was conducted at the Laboratory of Waste Recycling from Animal Production/FCA/UFGD. During four weeks, eight experimental digesters, semi-continuous models, were loaded and set according to the hydraulic retention time (HRT of 7, 14, 21 and 28 days, and according to the solid fraction treatment, separated with 1 mm sieve or without separation. The average weekly production of biogas and methane as well as the methane concentrations, the potential production per amount of chemical oxygen demand (COD added and reduced, the concentrations of N, P and K at the beginning and end of process, and the most likely numbers of total and thermotolerant coliforms were evaluated. For data analysis, a completely randomized design was performed in a 4 × 2 factorial arrangement (4 HRT: 7, 14, 21 and 28 days and separation with 1 mm sieve or without separation, with repetition over time. The highest production of biogas and methane was statistically significant for the HRT of 7 and 14 days (5.29 and 2.38 L of biogas and 4.28 and 1.73 L of methane, respectively. There was an interaction between HRT and the separation of the solid with sieve and the highest production was obtained in the treatment without separation. Similar behavior was observed for the potential production with a maximum of 0.41 m³ methane.kg-1 COD added with an HRT of 7 days without separation of the solid fraction. The separation of the solid fraction is not recommended in the pretreatment of liquid effluent from poultry slaughterhouse, once the potential for production and production of methane and biogas were reduced with this treatment.

  11. Ozonation and Thermal Pre-Treatment of Municipal Sewage Sludge-Implications for Toxicity and Methane Potential

    DEFF Research Database (Denmark)

    Davidsson, A.; Eriksson, Eva; Fick, J.

    2013-01-01

    The aim of this study was to determine effects on methane potential and overall sludge quality from two different sludge pre-treatment technologies (ozonation high/low dosage and thermal treatment 55/70 degrees C). In general both treatments produced increased methane potential. Thermal treatment...

  12. Ozonation and thermal pre-treatment of municipal sewage sludge – Implications for toxicity and methane potential

    DEFF Research Database (Denmark)

    Davidsson, A.; Eriksson, Eva; Fick, J.

    The aim of this study was to determine the effects on the methane potential and the overall sludge quality from two different sludge pre-treatment technologies (ozonation high/low dosage and thermal treatment 55/70 °C). In general both treatments gave an increased methane potential. The thermal...

  13. Biochemical methane potential and anaerobic biodegradability of non-herbaceous and herbaceous phytomass in biogas production

    DEFF Research Database (Denmark)

    Triolo, Jin Mi; Pedersen, Lene; Qu, Haiyan

    2012-01-01

    The suitability of municipal plant waste for anaerobic digestion was examined using 57 different herbaceous and non-herbaceous samples. Biochemical methane potential (BMP) and anaerobic biodegradability were related to the degree of lignification and crystallinity of cellulose. The BMP of herbace...

  14. An OxiTop (R) protocol for screening plant material for its biochemical methane potential (BMP)

    NARCIS (Netherlands)

    Pabon Pereira, C.P.; Castanares, G.; Lier, van J.B.

    2012-01-01

    A protocol was developed for determining the biochemical methane potential (BMP) of plant material using the OxiTop (R) system. NaOH pellets for CO2 absorption and different pretreatment methods were tested for their influence in the BMP test. The use of NaOH pellets in the headspace of the bottle n

  15. Bioenergy potential of Ulva lactuca: Biomass yield, methane production and combustion

    DEFF Research Database (Denmark)

    Bruhn, Annette; Dahl, Jonas; Bangsø Nielsen, Henrik

    2011-01-01

    The biomass production potential at temperate latitudes (56°N), and the quality of the biomass for energy production (anaerobic digestion to methane and direct combustion) were investigated for the green macroalgae, Ulva lactuca. The algae were cultivated in a land based facility demonstrating a ...... of bioenergy....

  16. Anaerobic co-digestion of perennials: Methane potential and digestate nitrogen fertilizer value

    DEFF Research Database (Denmark)

    Muller-Stover, Dorette Sophie; Sun, Guotao; Kroff, Pablo

    2016-01-01

    Co-digestion of crop biomass improves the traditional manure-based biogas yield due to an increased content of easily degradable carbon compounds. In this study, the methane potential of three perennials (grass, legumes, and grass+legume) was determined using various amounts together with animal...

  17. Biochemical methane potential tests of different autoclaved and microwaved lignocellulosic organic fractions of municipal solid waste.

    Science.gov (United States)

    Pecorini, Isabella; Baldi, Francesco; Carnevale, Ennio Antonio; Corti, Andrea

    2016-10-01

    The aim of this research was to enhance the anaerobic biodegradability and methane production of two synthetic Organic Fractions of Municipal Solid Waste with different lignocellulosic contents by assessing microwave and autoclave pre-treatments. Biochemical Methane Potential assays were performed for 21days. Changes in the soluble fractions of the organic matter (measured by soluble chemical oxygen demand, carbohydrates and proteins), the first order hydrolysis constant kh and the cumulated methane production at 21days were used to evaluate the efficiency of microwaving and autoclaving pretreatments on substrates solubilization and anaerobic digestion. Microwave treatment led to a methane production increase of 8.5% for both the tested organic fractions while autoclave treatment had an increase ranging from 1.0% to 4.4%. Results showed an increase of the soluble fraction after pre-treatments for both the synthetic organic fractions. Soluble chemical oxygen demand observed significant increases for pretreated substrates (up to 219.8%). In this regard, the mediocre results of methane's production led to the conclusion that autoclaving and microwaving resulted in the hydrolysis of a significant fraction of non-biodegradable organic substances recalcitrant to anaerobic digestion.

  18. Methane production potential (B0) of swine and cattle manures--a Canadian perspective.

    Science.gov (United States)

    Godbout, S; Verma, M; Larouche, J P; Potvin, L; Chapman, A M; Lemay, S P; Pelletier, F; Brar, S K

    2010-11-01

    Canada's agricultural emissions accounted for 60 Mt or 8% of national greenhouse gas (GHG) emissions in 2007. The estimation of CH4 emission factor (B0) from manure management systems in Canada is prone to uncertainty owing to lack of B0 values for Canadian conditions. Therefore, in this study, manure samples from six Canadian animal farms, two each of swine, beef and dairy cattle, were investigated in order to estimate their methane production potential (B0). The ultimate anaerobic biodegradability was measured with ISO standard batch fermentation. The extent of biodegradation of the manure samples with or without sodium benzoate was always greater than 60% and hence showed no inhibitory effect on methane production by the manure. The impact of use of antibiotics in the animal feed on methane production was also considered; however, no inhibitory effect on methane production could be observed. The plateau of methane production in all cases was achieved by 63 d of anaerobic digestion process and the final pH was within 6-8. The calculated B0 were in the range of 0.47-0.42, 0.21-0.19 and 0.35-0.30 for swine, beef cattle and dairy cattle, respectively. The uncertainties associated with B0 values were +/- 9% for swine, +/- 3% for beef cattle and, +/- 6 and +/- 2% for dairy cows.

  19. Methane and its Stable Isotope Signature Across Pennsylvania: Assessing the Potential Impacts of Natural Gas Development and Agriculture

    Science.gov (United States)

    Ramos-Garcés, F.; Fuentes, J. D.; Grannas, A. M.; Martins, D. K.

    2012-12-01

    Methane is an important greenhouse gas with a global warming potential 72 times that of carbon dioxide (20 year time horizon). Many recent efforts have been focused on improving our understanding of methane sources to the atmosphere and better quantifying the atmospheric methane budget. Increased natural gas exploration, particularly associated with shale gas drilling, has been hypothesized to be a potential source of atmospheric methane during well development and also due to fugitive emissions from operational well sites and pipelines. For a six-day period in June 2012, measurements of methane and its stable isotope signature were obtained from a mobile measurement platform using cavity ringdown spectroscopy. Transects from southwestern to northeastern Pennsylvania were studied, with samples obtained in rural, forested, urban, farm-impacted and well-impacted sites. Particular emphasis was placed on performing air sampling in the vicinity of natural gas wells under development, just completed, and in full operation. In the rural atmosphere, away from cattle farms and natural gas systems, the ambient levels of methane were around 1.75 ppm. Near and around gas wells under development, ambient methane levels resembled those found in the rural atmosphere. In some cases, the atmosphere was enriched with methane (up to 2.2 ppm) in areas near old wells and existing pipelines. Ambient methane levels around cattle farms were significantly enhanced, with mixing ratios reaching about 4 ppm. We will discuss here the impact of both gas well development and agricultural activities on observed methane concentrations and stable isotope signatures.

  20. Review: Assessing the climate mitigation potential of biomass

    Directory of Open Access Journals (Sweden)

    Patrick Moriarty

    2016-12-01

    Full Text Available For many millennia, humans have used biomass for three broad purposes: food for humans and fodder for farm animals; energy; and materials. Food has always been exclusively produced from biomass, and in the year 1800, biomass still accounted for about 95% of all energy. Biomass has also been a major source of materials for construction, implements, clothing, bedding and other uses, but some researchers think that total human uses of biomass will soon reach limits of sustainability. It is thus important to select those biomass uses that will maximise global climate change benefits. With a ‘food first’ policy, it is increasingly recognised that projections of food needs are important for estimating future global bioenergy potential, and that non-food uses of biomass can be increased by both food crop yield improvements and dietary changes. However, few researchers have explicitly included future biomaterials production as a factor in bioenergy potential. Although biomaterials’ share of the materials market has roughly halved over the past quarter-century, we show that per tonne of biomass, biomaterials will usually allow greater greenhouse gas reductions than directly using biomass for bioenergy. particularly since in many cases, biomaterials can be later burnt for energy after their useful life.

  1. French Brittany macroalgae screening: composition and methane potential for potential alternative sources of energy and products.

    Science.gov (United States)

    Jard, G; Marfaing, H; Carrère, H; Delgenes, J P; Steyer, J P; Dumas, C

    2013-09-01

    Macroalgae are biomass resources that represent a valuable feedstock to be used entirely for human consumption or for food additives after some extractions (mainly colloids) and/or for energy production. In order to better develop the algal sector, it is important to determine the capacity of macroalgae to produce these added-values molecules for food and/or for energy industries on the basis of their biochemical characteristics. In this study, ten macroalgae obtained from French Brittany coasts (France) were selected. The global biochemical composition (proteins, lipids, carbohydrates, fibers), the presence and characteristics of added-values molecules (alginates, polyphenols) and the biochemical methane potential of these algae were determined. Regarding its biochemical composition, Palmaria palmata is interesting for food (rich in nutrients) and for anaerobic digestion (0.279 LCH4/gVS). Saccharina latissima could be used for alginate extraction (242 g/kgTS, ratio between mannuronic and guluronic acid M/G=1.4) and Sargassum muticum for polyphenol extraction (19.8 g/kgTS).

  2. Improvement of direct-wet-seeding rice yield and methane mitigation under water and fertilizer managements and comparison of its economic returns

    Directory of Open Access Journals (Sweden)

    Saisompan, C.

    2004-11-01

    Full Text Available In order to increase rice yields (RY while reducing methane gas emissions (ME, several strategies for methane mitigation were compared in a trial during the second rice growing season of 2003. A split plot design was used, consisting of 2 water management (WM treatments in main plots: 1 continuous flooding and 2 intermittent drainage (by letting water evapotranspirate or drain away so as to maintain the soil moisture content approximately at field capacity during a part of the maximum tillering and flowering stages; and five introgen (N fertilizer treatments in sub plots: 1 no top- dressing of ferlilizers, 2 top-dressing of ammonium fulfate (AS, 21% N at 15 kg per rai, 3 AS at 30 kg per rai, 4 urea (46%N at 7 kg per rai and 5 urea at 14 kg per rai. All plots received 16-16-8 at the rate of 20 kg per rai as a basal application. Results indicate that WM had no significant effect on RY, but that intermittent flooding resulted in significantly less methane emission than continuous flooding. Top-dressing of N fertilizers had significant effect on both RY and ME. Top-dressing of urea at the rate of 14 kg per rai resulted in the highest RY, 912 kg per rai,followed by top-dressing of AS at 30 kg per rai, which produced a yield of 874 kg per rai. Application of 30 kg per rai of AS was more effective in decreasing in both total methane emission (TME and methane emission per unit grain yield (MPG than the application of 14 kg per rai of urea. However, the highest benefit of 1,920 baht per rai and the highest income-cost ratio (I/C of 2.11 were obtained by top-dressing of 14 kg per rai of urea. The next best treatment was the application of AS at the rate of 30 kg per rai which resulted in a benefit of 1,727 baht per rai, and I/C of 1.98. It was concluded that a basal application of 16-16-8 at the rate of 20 kg per rai, followed by to-dressing with eith AS at 30 kg per rai or urea at 14 kg per rai (both equivalent to approximately 6 kg N per rai and

  3. Evaluation and modeling of biochemical methane potential (BMP) of landfilled solid waste: a pilot scale study

    DEFF Research Database (Denmark)

    Bilgili, M Sinan; Demir, Ahmet; Varank, Gamze

    2009-01-01

    The main goal of this study was to present a comparison of landfill performance with respect to solids decomposition. Biochemical methane potential (BMP) test was used to determine the initial and the remaining CH(4) potentials of solid wastes during 27 months of landfilling operation in two pilot...... and R2 reactors were 0.01571 and 0.01195 1/d, respectively. The correlation between the model and the experimental parameters was more than 95%, showing the good fit of the model....

  4. Enhancing anaerobic digestion of food waste through biochemical methane potential assays at different substrate: inoculum ratios.

    Science.gov (United States)

    Hobbs, Shakira R; Landis, Amy E; Rittmann, Bruce E; Young, Michelle N; Parameswaran, Prathap

    2017-06-28

    Food waste has a high energy potential that can be converted into useful energy in the form of methane via anaerobic digestion. Biochemical Methane Potential assays (BMPs) were conducted to quantify the impacts on methane production of different ratios of food waste. Anaerobic digester sludge (ADS) was used as the inoculum, and BMPs were performed at food waste:inoculum ratios of 0.42, 1.42, and 3.0g chemical oxygen demand/g volatile solids (VS). The 1.42 ratio had the highest CH4-COD recovery: 90% of the initial total chemical oxygen demand (TCOD) was from food waste, followed by ratios 0.42 and 3.0 at 69% and 57%, respectively. Addition of food waste above 0.42 caused a lag time for CH4 production that increased with higher ratios, which highlighted the negative impacts of overloading with food waste. The Gompertz equation was able to represent the results well, and it gave lag times of 0, 3.6 and 30days and maximum methane productions of 370, 910, and 1950mL for ratios 0.42, 1.42 and 3.0, respectively. While ratio 3.0 endured a long lag phase and low VSS destruction, ratio 1.42 achieved satisfactory results for all performance criteria. These results provide practical guidance on food-waste-to-inoculum ratios that can lead to optimizing methanogenic yield. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Enhanced-efficiency nitrogen fertilizers: potential role in nitrous oxide emission mitigation

    Science.gov (United States)

    Enhanced-efficiency N fertilizers (EENF) have potential for mitigating N2O emissions from N fertilized cropping systems. A synopsis of EENF characteristics is presented. Stabilized EENFs contain nitrification and/or urease inhibitors. Slow-release EENFs contain N components that are slowly releas...

  6. Challenging the claims on the potential of biochar to mitigate climate change

    NARCIS (Netherlands)

    Francischinelli Rittl, T.

    2015-01-01

    Summary In this PhD thesis I studied the influence of biochar discourses on the political practices in Brazil and the impact of biochar on soil organic carbon (SOC) stocks, thus contributing to the current debate on the potential of biochar to mitigate climate change. Biochar is the solid material o

  7. 76 FR 14413 - Risk Mitigation Strategies To Address Potential Procoagulant Activity in Immune Globulin...

    Science.gov (United States)

    2011-03-16

    ...) pathophysiology of arterial and venous thrombosis in this context; (3) research to identify specific procoagulant...) the role of activated Coagulation Factor XIa in IGIV-associated thrombosis; (6) test methods for... HUMAN SERVICES Food and Drug Administration Risk Mitigation Strategies To Address Potential...

  8. Challenging the claims on the potential of biochar to mitigate climate change

    NARCIS (Netherlands)

    Francischinelli Rittl, T.

    2015-01-01

    Summary In this PhD thesis I studied the influence of biochar discourses on the political practices in Brazil and the impact of biochar on soil organic carbon (SOC) stocks, thus contributing to the current debate on the potential of biochar to mitigate climate change. Biochar is the solid material

  9. An Alternative View of the Climate Warming Mitigation Potential of U.S. Temperate Forests

    Science.gov (United States)

    Many U.S. federal and non-governmental agencies promote forestation as a means to mitigate climate warming because of the carbon sequestration potential of forests. This biogeochemical-oriented carbon sequestration policy is somewhat inconsistent with a decade or more of researc...

  10. The potential for biologically catalyzed anaerobic methane oxidation on ancient Mars.

    Science.gov (United States)

    Marlow, Jeffrey J; Larowe, Douglas E; Ehlmann, Bethany L; Amend, Jan P; Orphan, Victoria J

    2014-04-01

    This study examines the potential for the biologically mediated anaerobic oxidation of methane (AOM) coupled to sulfate reduction on ancient Mars. Seven distinct fluids representative of putative martian groundwater were used to calculate Gibbs energy values in the presence of dissolved methane under a range of atmospheric CO2 partial pressures. In all scenarios, AOM is exergonic, ranging from -31 to -135 kJ/mol CH4. A reaction transport model was constructed to examine how environmentally relevant parameters such as advection velocity, reactant concentrations, and biomass production rate affect the spatial and temporal dependences of AOM reaction rates. Two geologically supported models for ancient martian AOM are presented: a sulfate-rich groundwater with methane produced from serpentinization by-products, and acid-sulfate fluids with methane from basalt alteration. The simulations presented in this study indicate that AOM could have been a feasible metabolism on ancient Mars, and fossil or isotopic evidence of this metabolic pathway may persist beneath the surface and in surface exposures of eroded ancient terrains.

  11. Methane Potential and Enzymatic Saccharification of Steam-exploded Bagasse

    Directory of Open Access Journals (Sweden)

    Vivekanand Vivekanand

    2014-01-01

    Full Text Available To evaluate the biofuel potential of bagasse, an abundant co-product in sugarcane-based industries, the effect of steam explosion on the efficiency of enzymatic saccharification and anaerobic digestion was studied. Bagasse was steam exploded at four different severity levels, and the impact of pretreatment was evaluated by analyzing the release of glucose after enzymatic saccharification with Cellic CTec2 and by analyzing methane production during anaerobic batch digestions. Increasing the severity of pretreatment led to degradation of xylan and the formation of pseudo-lignin. The severity of pretreatment was correlated with the enzymatic release of glucose; at optimal conditions, > 90% of the glucan was released. The highest methane yield (216 mL/gVS was 1.3 times higher than the yield from untreated bagasse. More importantly, the pretreatment dramatically increased the rate of methane production; after 10 days, methane production from pretreated material was approximately twice that of the untreated material. To assess the possibility of developing combined processes, steam-exploded bagasse was enzymatically pre-hydrolyzed and, after the removal of released sugars, the remaining solid was subjected to anaerobic digestion. The results indicated that, in terms of total heating value, combined ethanol and biogas production is as beneficial as producing only biogas.

  12. Impacts of inoculum pre-treatments on enzyme activity and biochemical methane potential.

    Science.gov (United States)

    Wang, Bing; Strömberg, Sten; Nges, Ivo Achu; Nistor, Mihaela; Liu, Jing

    2016-05-01

    Biochemical methane potential (BMP) tests were carried out to investigate the influence of inoculum pre-treatments (filtration and pre-incubation) on methane production from cellulose and wheat straw. First-order model and Monod model were used to evaluate the kinetic constants of the BMP assays. The results demonstrated that fresh inoculum was the best option to perform BMP tests. This was evidenced by highest enzyme activity (0.11 U/mL) and highest methane yields for cellulose (356 NmL CH4/gVS) as well as wheat straw (261 NmL CH4/gVS). Besides, high biodegradability (85.8% for cellulose and 61.3% for wheat straw) was also obtained when the fresh inoculum was used. Moreover, a kinetic evaluation showed that inoculum pre-incubation at 37°C or storage at 4°C introduced a lag-time whereas the effects on hydrolysis rate were less consequent. In summary, pre-treatments affected the enzyme activity of the inoculum, and further on, significantly influenced the methane production and the degradation kinetics of the investigated substrates. It is recommended that filtration of inoculum should be avoided unless in case too large particles therein.

  13. Why can water cages adsorb aqueous methane? A potential of mean force calculation on hydrate nucleation mechanisms.

    Science.gov (United States)

    Guo, Guang-Jun; Li, Meng; Zhang, Yi-Gang; Wu, Chang-Hua

    2009-11-28

    By performing constrained molecular dynamics simulations in the methane-water system, we successfully calculated the potential of mean force (PMF) between a dodecahedral water cage (DWC) and dissolved methane for the first time. As a function of the distance between DWC and methane, this is characterized by a deep well at approximately 6.2 A and a shallow well at approximately 10.2 A, separated by a potential barrier at approximately 8.8 A. We investigated how the guest molecule, cage rigidity and the cage orientation affected the PMF. The most important finding is that the DWC itself strongly adsorbs methane and the adsorption interaction is independent of the guests. Moreover, the activation energy of the DWC adsorbing methane is comparable to that of hydrogen bonds, despite differing by a factor of approximately 10% when considering different water-methane interaction potentials. We explain that the cage-methane adsorption interaction is a special case of the hydrophobic interaction between methane molecules. The strong net attraction in the DWC shell with radii between 6.2 and 8.8 A may act as the inherent driving force that controls hydrate formation. A cage adsorption hypothesis for hydrate nucleation is thus proposed and discussed.

  14. Global emissions of fluorinated greenhouse gases until 2050: technical mitigation potentials and costs

    Science.gov (United States)

    Purohit, Pallav; Hoglund-Isaksson, Lena

    2016-04-01

    The anthropogenic fluorinated (F-gases) greenhouse gas emissions have increased significantly in recent years and are estimated to rise further in response to increased demand for cooling services and the phase out of ozone-depleting substances (ODS) under the Montreal Protocol. F-gases (HFCs, PFCs and SF6) are potent greenhouse gases, with a global warming effect up to 22,800 times greater than carbon dioxide (CO2). This study presents estimates of current and future global emissions of F-gases, their technical mitigation potential and associated costs for the period 2005 to 2050. The analysis uses the GAINS model framework to estimate emissions, mitigation potentials and costs for all major sources of anthropogenic F-gases for 162 countries/regions, which are aggregated to produce global estimates. For each region, 18 emission source sectors with mitigation potentials and costs were identified. Global F-gas emissions are estimated at 0.7 Gt CO2eq in 2005 with an expected increase to about 3.6 Gt CO2eq in 2050. There are extensive opportunities to reduce emissions by over 95 percent primarily through replacement with existing low GWP substances. The initial results indicate that at least half of the mitigation potential is attainable at a cost of less than 20€ per t CO2eq, while almost 90 percent reduction is attainable at less than 100€ per t CO2eq. Currently, several policy proposals have been presented to amend the Montreal Protocol to substantially curb global HFC use. We analyze the technical potentials and costs associated with the HFC mitigation required under the different proposed Montreal Protocol amendments.

  15. Mitigating greenhouse gas emissions with agricultural land management changes: What practices hold the best potential?

    Science.gov (United States)

    Eagle, A. J.; Olander, L.; Rice, C. W.; Haugen-Kozyra, K.; Henry, L. R.; Baker, J. S.; Jackson, R. B.

    2010-12-01

    Agricultural land management practices within the United States have significant potential to mitigate greenhouse gases (GHGs) in voluntary market or regulatory contexts - by sequestering soil carbon or reducing N2O or CH4 emissions. Before these practices can be utilized in active protocols or within a regulatory or farm bill framework, we need confidence in our ability to determine their impact on GHG emissions. We develop a side-by-side comparison of mitigation potential and implementation readiness for agricultural GHG mitigation practices, with an extensive literature review. We also consider scientific certainty, environmental and social co-effects, economic factors, regional specificity, and possible implementation barriers. Biophysical GHG mitigation potential from agricultural land management activities could reach more than 500 Mt CO2e/yr in the U.S. (7.1% of annual emissions). Up to 75% of the total potential comes from soil C sequestration. Economic potential is lower, given necessary resources to incentivize on-farm adaptations, but lower cost activities such as no-till, fertilizer N management, and cover crops show promise for near-term implementation in certain regions. Scientific uncertainty or the need for more research limit no-till and rice water management in some areas; and technical or other barriers need to be addressed before biochar, advanced crop breeding, and agroforestry can be widely embraced for GHG mitigation. Significant gaps in the current research and knowledge base exist with respect to interactions between tillage and N2O emissions, and with fertilizer application timing impacts on N2O emissions.

  16. Composition, texture and methane potential of cellulosic residues from Lewis acids organosolv pulping of wheat straw.

    Science.gov (United States)

    Constant, Sandra; Barakat, Abdellatif; Robitzer, Mike; Di Renzo, Francesco; Dumas, Claire; Quignard, Françoise

    2016-09-01

    Cellulosic pulps have been successfully isolated from wheat straw through a Lewis acids organosolv treatment. The use of Lewis acids with different hardness produced pulps with different delignification degrees. The cellulosic residue was characterised by chemical composition, X-ray diffraction, FT-IR spectroscopy, N2 physisorption, scanning electron microscopy and potential for anaerobic digestibility. Surface area and pore volume increased with the hardness of the Lewis acid, in correspondence with the decrease of the amount of lignin and hemicellulose in the pulp. The non linearity of the correlation between porosity and composition suggests that an agglomeration of cellulose fibrils occurs in the early stages of pulping. All organosolv pulps presented a significantly higher methane potential than the parent straw. A methane evolution of 295Ncm(3)/g OM was reached by a moderate improvement of the accessibility of the native straw.

  17. The potential contribution to climate change mitigation from temporary carbon storage in biomaterials

    DEFF Research Database (Denmark)

    Jørgensen, Susanne Vedel; Hauschild, Michael Zwicky; Nielsen, Per H.

    2015-01-01

    of biomaterials.The recently developed approach for quantifying the climate tipping potential (CTP) of emissions is used, with some adaption, to account for the value of temporary carbon storage. CTP values for short-, medium- and long-term carbon storage in chosen biomaterials are calculated for two possible...... future atmospheric greenhouse gas (GHG) concentration development scenarios. The potential magnitude of the temporary carbon storage in biomaterials is estimated by considering the global polymer production being biobased in the future.Both sets of CTP values show the same trend; storage which releases...... contributes with negative CTP values, which means mitigation. The longer the duration of the storage, the larger the mitigation potential.Temporary carbon storage in biomaterials has a potential for contributing to avoid or postpone the crossing of a climatic target level of 450 ppm CO2e, depending on GHG...

  18. The potential for biomass to mitigate greenhouse gas emissions in the Northeastern US. Northeast Regional Biomass Program

    Energy Technology Data Exchange (ETDEWEB)

    Bernow, S.S.; Gurney, K.; Prince, G.; Cyr, M.

    1992-04-01

    This study, for the Northeast Regional Biomass Program (NRBP) of the Coalition of Northeast Governors (CONEG), evaluates the potential for local, state and regional biomass policies to contribute to an overall energy/biomass strategy for the reduction of greenhouse gas releases in the Northeastern United States. Biomass is a conditionally renewable resource that can play a dual role: by reducing emissions of greenhouse gases in meeting our energy needs; and by removing carbon from the atmosphere and sequestering it in standing biomass stocks and long-lived products. In this study we examine the contribution of biomass to the energy system in the Northeast and to the region`s net releases of carbon dioxide and methane, and project these releases over three decades, given a continuation of current trends and policies. We then compare this Reference Case with three alternative scenarios, assuming successively more aggressive efforts to reduce greenhouse gas emissions through strategic implementation of energy efficiency and biomass resources. Finally, we identify and examine policy options for expanding the role of biomass in the region`s energy and greenhouse gas mitigation strategies.

  19. Temperature response of methane oxidation and production potentials in peatland ecosystems across Finland

    Science.gov (United States)

    Welti, Nina; Korrensalo, Aino; Kerttula, Johanna; Maljanen, Marja; Uljas, Salli; Lohila, Annalea; Laine, Anna; Vesala, Timo; Elliott, David; Tuittila, Eeva-Stiina

    2016-04-01

    It has been suggested that the ecosystems located in the high latitudes are especially sensitive to warming. Therefore, we compared 14 peatland systems throughout Finland along a latitudinal gradient from 69°N to 61°N to examine the response of methane production and methane oxidation with warming climate. Peat samples were taken at the height of the growing season in 2015 from 0 - 10cm below the water table depth. The plant communities in sampling locations were described by estimating cover of each plant species and pH of water was measured. Upon return to the lab, we made two parallel treatments, under anoxic and oxic conditions in order to calculate the CH4 production and consumption potentials of the peat and used three temperatures, 4°C, 17.5°C, and 30°C to examine the temperature effect on the potentials. We hypothesized that there will be an observable response curve in CH4 production and oxidation relative to temperature with a greater response with increasing latitude. In general, increasing temperature increased the potential for CH4 production and oxidation, at some sites, the potential was highest at 17.5°C, indicating that there is an optimum temperature threshold for the in situ methane producing and oxidizing microbial communities. Above this threshold, the peat microbial communities are not able to cope with increasing temperature. This is especially noticeable for methane oxidation at sites above 62°N. As countries are being expected to adequately account for their greenhouse gas budgets with increasing temperature models, knowing where the temperature threshold exists is of critical importance.

  20. Evaluation of the Effects of Mitigation on Methane and Ammonia Production by Using Origanum vulgare L. and Rosmarinus officinalis L. Essential Oils on in Vitro Rumen Fermentation Systems

    Directory of Open Access Journals (Sweden)

    Gabriella Cobellis

    2015-09-01

    Full Text Available The effects of increasing concentrations of oregano (Origanum vulgare L. and rosemary (Rosmarinus officinalis L. essentials oil (EO on ruminal gas emissions were tested in vitro using 50 mL serum bottles. Each bottle contained a 200 mg substrate (alfalfa hay and corn meal 1:1 and a 20 mL solution composed of a buffered medium and rumen fluid (1:2. The percentage of ruminal fermentation products was quantified by an infrared analyzer. The reduction of total gas production was 6% and 9% respectively when using the 1.5 and 2.0 g/L oregano EO measurements. The reduction of methane production was 55%, 72% and 71% respectively with regard to the 1.0, 1.5 and 2.0 g/L oregano EO doses, while rosemary EO (2.0 g/L reduced the methane production by 9%. The production of ammonia was significantly reduced (59%–78% by all treatments with the exception of rosemary EO at the lowest dose. Dry matter and neutral detergent fiber degradability was reduced by most of the treatments (respectively 4%–9% and 8%–24%. The total volatile fatty acids (VFA concentration was markedly decreased by oregano EO and was not affected by rosemary EO. Both EOs mitigated rumen fermentations, but oregano EO gave rise to the highest reduction in methane and ammonia production. However, further research is needed to evaluate the use of these essential oils as dietary supplements by taking into account the negative effects on feed degradability.

  1. Air Force is Developing Risk-Mitigation Strategies to Manage Potential Loss of the RD-180 Engine (REDACTED)

    Science.gov (United States)

    2015-03-05

    Mitigation Study; however, they developed risk -mitigation strategies to manage the potential loss of the RD-180 engine. Therefore, we are not making...Force is Developing Risk -Mitigation Strategies to Manage Potential Loss of the RD-180 Engine (Report No. DODIG-2015-086) We are providing the enclosed...for liquid oxygenihydrocarbon-fueled rocket engine technology risk reduction. Partially ~) SAF/AQ slated il was premature to choose aspecific engine

  2. Dynamics and climate change mitigation potential of soil organic carbon sequestration.

    Science.gov (United States)

    Sommer, Rolf; Bossio, Deborah

    2014-11-01

    When assessing soil organic carbon (SOC) sequestration and its climate change (CC) mitigation potential at global scale, the dynamic nature of soil carbon storage and interventions to foster it should be taken into account. Firstly, adoption of SOC-sequestration measures will take time, and reasonably such schemes could only be implemented gradually at large-scale. Secondly, if soils are managed as carbon sinks, then SOC will increase only over a limited time, up to the point when a new SOC equilibrium is reached. This paper combines these two processes and predicts potential SOC sequestration dynamics in agricultural land at global scale and the corresponding CC mitigation potential. Assuming that global governments would agree on a worldwide effort to gradually change land use practices towards turning agricultural soils into carbon sinks starting 2014, the projected 87-year (2014-2100) global SOC sequestration potential of agricultural land ranged between 31 and 64 Gt. This is equal to 1.9-3.9% of the SRES-A2 projected 87-year anthropogenic emissions. SOC sequestration would peak 2032-33, at that time reaching 4.3-8.9% of the projected annual SRES-A2 emission. About 30 years later the sequestration rate would have reduced by half. Thus, SOC sequestration is not a C wedge that could contribute increasingly to mitigating CC. Rather, the mitigation potential is limited, contributing very little to solving the climate problem of the coming decades. However, we deliberately did not elaborate on the importance of maintaining or increasing SOC for sustaining soil health, agro-ecosystem functioning and productivity; an issue of global significance that deserves proper consideration irrespectively of any potential additional sequestration of SOC.

  3. Effects of three methane mitigation agents on parameters of kinetics of total and hydrogen gas production, ruminal fermentation and hydrogen balance using in vitro technique.

    Science.gov (United States)

    Wang, Min; Wang, Rong; Yang, Shan; Deng, Jin Ping; Tang, Shao Xun; Tan, Zhi Liang

    2016-02-01

    Methane (CH4 ) can be mitigated through directly inhibiting methanogen activity and starving methanogens by hydrogen (H2 ) sink. Three types of mechanism (i.e. bromoethanesulphonate (BES), nitrate and emodin) and doses of CH4 mitigation agents were employed to investigate their pathways of CH4 inhibition. Results indicated that both BES and emodin inhibited CH4 production and altered H2 balance, which could be accompanied by decreased dry matter disappearance (DMD), fractional rate of gH2 formation, volatile fatty acid (VFA) production, ability to produce and use reducing equivalences and molecular H2 , and increased final asymptotic gH2 production, time to the peak of gH2 , discrete lag time of gH2 production and fermentation efficiency. However, emodin decreased gas volume produced by rapidly fermentable components of substrate and the rate of fermentation at early stage of incubation, while BES supplementation inhibited gas volume produced by both rapidly and slowly fermentable components of substrate and the rate of fermentation at middle or late stage of incubation. The nitrate supplementation inhibited CH4 production without affecting VFA profile, because of its dual role as H2 sink and being toxic to methanogens. Nitrate supplementation had more complicated pattern of fermentation, VFA production and profile and H2 balance in comparison to BES and emodin supplementation.

  4. Biochemical methane potential (BMP) of solid organic substrates: evaluation of anaerobic biodegradability using data from an international interlaboratory study

    NARCIS (Netherlands)

    Raposo, F.; Fernandez-Cegri, V.; Rubia, de la M.A.; Borja, R.; Beline, F.; Cavinato, C.; Demirer, G.; Fernandez, B.; Fernandez-Polanco, M.; Frigon, J.C.; Ganesh, R.; Kaparaju, P.; Koubova, J.; Mendez, R.; Menin, G.; Peene, A.; Scherer, P.; Torrijos, M.; Uellendahl, H.; Wierinck, I.; Wilde, de V.

    2011-01-01

    BACKGROUND: This paper describes results obtained for different participating research groups in an interlaboratory study related to biochemical methane potential (BMP). In this research work, all experimental conditions influencing the test such as inoculum, substrate characteristics and

  5. Biochemical methane potential (BMP) of solid organic substrates: evaluation of anaerobic biodegradability using data from an international interlaboratory study

    NARCIS (Netherlands)

    Raposo, F.; Fernandez-Cegri, V.; Rubia, de la M.A.; Borja, R.; Beline, F.; Cavinato, C.; Demirer, G.; Fernandez, B.; Fernandez-Polanco, M.; Frigon, J.C.; Ganesh, R.; Kaparaju, P.; Koubova, J.; Mendez, R.; Menin, G.; Peene, A.; Scherer, P.; Torrijos, M.; Uellendahl, H.; Wierinck, I.; Wilde, de V.

    2011-01-01

    BACKGROUND: This paper describes results obtained for different participating research groups in an interlaboratory study related to biochemical methane potential (BMP). In this research work, all experimental conditions influencing the test such as inoculum, substrate characteristics and experiment

  6. Study of Monte Carlo Simulation Method for Methane Phase Diagram Prediction using Two Different Potential Models

    KAUST Repository

    Kadoura, Ahmad

    2011-06-06

    Lennard‐Jones (L‐J) and Buckingham exponential‐6 (exp‐6) potential models were used to produce isotherms for methane at temperatures below and above critical one. Molecular simulation approach, particularly Monte Carlo simulations, were employed to create these isotherms working with both canonical and Gibbs ensembles. Experiments in canonical ensemble with each model were conducted to estimate pressures at a range of temperatures above methane critical temperature. Results were collected and compared to experimental data existing in literature; both models showed an elegant agreement with the experimental data. In parallel, experiments below critical temperature were run in Gibbs ensemble using L‐J model only. Upon comparing results with experimental ones, a good fit was obtained with small deviations. The work was further developed by adding some statistical studies in order to achieve better understanding and interpretation to the estimated quantities by the simulation. Methane phase diagrams were successfully reproduced by an efficient molecular simulation technique with different potential models. This relatively simple demonstration shows how powerful molecular simulation methods could be, hence further applications on more complicated systems are considered. Prediction of phase behavior of elemental sulfur in sour natural gases has been an interesting and challenging field in oil and gas industry. Determination of elemental sulfur solubility conditions helps avoiding all kinds of problems caused by its dissolution in gas production and transportation processes. For this purpose, further enhancement to the methods used is to be considered in order to successfully simulate elemental sulfur phase behavior in sour natural gases mixtures.

  7. Anaerobic Biodegradability and Methane Potential of Crop Residue Co-Digested with Buffalo Dung

    Directory of Open Access Journals (Sweden)

    Abdul Razaque Sahito

    2013-07-01

    Full Text Available ABD (Anaerobic Biodegradability and BMP (Biochemical Methane Potential of banana plant waste, canola straw, cotton stalks, rice straw, sugarcane trash and wheat straw co-digested with buffalo dung was evaluated through AMPTS (Automatic Methane Potential Test System. The substrates were analyzed for moisture, TS (Total Solids and VS (Volatile Solids, ultimate analysis (CHONS, pH and TA (Total Alkalinity. The BMPobserved during incubation of 30 days at the temperature of 37±0.2°C was 322 Nml CH4/g VSadd for wheat straw followed by 260, 170, 149, 142 and 138 Nml CH4/gVSadd for canola straw, rice straw, cotton stalks, banana plant waste and sugarcane trash respectively, whereas the maximum theoretical BMP was 481 Nml CH4/gVSadd for cotton stalks, followed by 473, 473, 446, 432 and 385 Nml CH4/gVSadd for wheat straw, banana plant waste, canola straw, rice straw and sugarcane trash respectively. The percentage ABD values were in the range of 68-30%. In addition to this, the effect of lignin content in the crop residue was evaluated on the ABD. The results of this study indicate that, the co-digestion of the crop residues with buffalo dung is feasible for production of renewable methane

  8. Evaluating the biochemical methane potential (BMP) of low-organic waste at Danish landfills

    DEFF Research Database (Denmark)

    Mou, Zishen; Scheutz, Charlotte; Kjeldsen, Peter

    2014-01-01

    The biochemical methane potential (BMP) is an essential parameter when using first order decay (FOD) landfill gas (LFG) generation models to estimate methane (CH4) generation from landfills. Different categories of waste (mixed, shredder and sludge waste) with a low-organic content and temporarily...... stored combustible waste were sampled from four Danish landfills. The waste was characterized in terms of physical characteristics (TS, VS, TC and TOC) and the BMP was analyzed in batch tests. The experiment was set up in triplicate, including blank and control tests. Waste samples were incubated at 55 C...... for more than 60 days, with continuous monitoring of the cumulative CH4 generation. Results showed that samples of mixed waste and shredder waste had similar BMP results, which was in the range of 5.4–9.1 kg CH4/ton waste (wet weight) on average. As a calculated consequence, their degradable organic carbon...

  9. Quantification of the Potential Gross Economic Impacts of Five Methane Reduction Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Keyser, David [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Warner, Ethan [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Curley, Christina [Colorado State Univ., Fort Collins, CO (United States)

    2015-04-23

    Methane (CH4) is a potent greenhouse gas that is released from the natural gas supply chain into the atmosphere as a result of fugitive emissions1 and venting2 . We assess five potential CH4 reduction scenarios from transmission, storage, and distribution (TS&D) using published literature on the costs and the estimated quantity of CH4 reduced. We utilize cost and methane inventory data from ICF (2014) and Warner et al. (forthcoming) as well as data from Barrett and McCulloch (2014) and the American Gas Association (AGA) (2013) to estimate that the implementation of these measures could support approximately 85,000 jobs annually from 2015 to 2019 and reduce CH4 emissions from natural gas TS&D by over 40%. Based on standard input/output analysis methodology, measures are estimated to support over $8 billion in GDP annually over the same time period and allow producers to recover approximately $912 million annually in captured gas.

  10. An OxiTop(®) protocol for screening plant material for its biochemical methane potential (BMP).

    Science.gov (United States)

    Pabón Pereira, C P; Castañares, G; van Lier, J B

    2012-01-01

    A protocol was developed for determining the biochemical methane potential (BMP) of plant material using the OxiTop(®) system. NaOH pellets for CO(2) absorption and different pretreatment methods were tested for their influence in the BMP test. The use of NaOH pellets in the headspace of the bottle negatively affected the stability of the test increasing the pH and inhibiting methanization. Sample comminution increased the biodegradability of plant samples. Our results clearly indicate the importance of test conditions during the assessment of anaerobic biodegradability of plant material, considering BMP differences as high as 44% were found. Guidelines and recommendations are given for screening plant material suitable for anaerobic digestion using the OxiTop(®) system.

  11. Effects of Substrate to Inoculum Ratio on the Biochemical Methane Potential of Piggery Slaughterhouse Wastes

    Science.gov (United States)

    Yoon, Young-Man; Kim, Seung-Hwan; Shin, Kook-Sik; Kim, Chang-Hyun

    2014-01-01

    The aim of this study was to assess the effect of substrate to inoculum ratio (S/I ratio) on the biochemical methane potential (BMP) and anaerobic biodegradability (Ddeg) of different piggery slaughterhouse wastes, such as piggery blood, intestine residue, and digestive tract content. These wastes were sampled from a piggery slaughterhouse located in Kimje, South Korea. Cumulative methane production curves for the wastes were obtained from the anaerobic batch fermentation having different S/I ratios of 0.1, 0.5, 1.0, and 1.5. BMP and anaerobic biodegradabilities (Ddeg) of the wastes were calculated from cumulative methane production data for the tested conditions. At the lowest S/I ration of 0.1, BMPs of piggery blood, intestine residue, and digestive tract content were determined to be 0.799, 0.848, and 1.076 Nm3 kg−1-VSadded, respectively, which were above the theoretical methane potentials of 0.539, 0.644, and 0.517 Nm3 kg−1-VSadded for blood, intestine residue, and digestive tract content, respectively. However, BMPs obtained from the higher S/I ratios of 0.5, 1.0, and 1.5 were within the theoretical range for all three types of waste and were not significantly different for the different S/I ratios tested. Anaerobic biodegradabilities calculated from BMP data showed a similar tendency. These results imply that, for BMP assay in an anaerobic reactor, the S/I ratio of anaerobic reactor should be above 0.1 and the inoculum should be sufficiently stabilized to avoid further degradation during the assay. PMID:25049994

  12. Mitigation potential and cost in tropical forestry - relative role for agroforestry

    Energy Technology Data Exchange (ETDEWEB)

    Makundi, Willy R.; Sathaye, Jayant A.

    2004-01-01

    This paper summarizes studies of carbon mitigation potential (MP) and costs of forestry options in seven developing countries with a focus on the role of agroforestry. A common methodological approach known as comprehensive mitigation assessment process (COMAP) was used in each study to estimate the potential and costs between 2000 and 2030. The approach requires the projection of baseline and mitigation land-use scenarios derived from the demand for forest products and forestland for other uses such as agriculture and pasture. By using data on estimated carbon sequestration, emission avoidance, costs and benefits, the model enables one to estimate cost effectiveness indicators based on monetary benefit per t C, as well as estimates of total mitigation costs and potential when the activities are implemented at equilibrium level. The results show that about half the MP of 6.9 Gt C (an average of 223 Mt C per year) between 2000 and 2030 in the seven countries could be achieved at a negative cost, and the other half at costs not exceeding $100 per t C. Negative cost indicates that non-carbon revenue is sufficient to offset direct costs of about half of the options. The agroforestry options analyzed bear a significant proportion of the potential at medium to low cost per t C when compared to other options. The role of agroforestry in these countries varied between 6% and 21% of the MP, though the options are much more cost effective than most due to the low wage or opportunity cost of rural labor. Agroforestry options are attractive due to the large number of people and potential area currently engaged in agriculture, but they pose unique challenges for carbon and cost accounting due to the dispersed nature of agricultural activities in the tropics, as well as specific difficulties arising from requirements for monitoring, verification, leakage assessment and the establishment of credible baselines.

  13. The Good, the Bad, and the Ugly: Comparing the Climate Mitigation Potential of Advanced Biofuels

    Science.gov (United States)

    Cassidy, E. S.

    2014-12-01

    The federal policy known as the Renewable Fuel Standard mandates that by 2022, 21 billion gallons of advanced biofuels will be used in the U.S. fuel supply. So far this policy has resulted in drastically increased production of corn ethanol and only a small amount of advanced fuels. While most corn ethanol plants are not required to achieve a reduction in greenhouse gas emissions (when compared to gasoline), advanced biofuels are required to reduce emissions by 50 or 60 percent. But not all fuels that qualify for advanced status according to the Environmental Protection Agency have the same climate mitigation potential. This study ranks advanced fuel pathways approved by the EPA from good, to bad…to worse. Climate mitigation potential of these fuels is compared to previous research and examined using the EPA's modeling framework.

  14. Assessment of process control parameters in the biochemical methane potential of sunflower oil cake

    Energy Technology Data Exchange (ETDEWEB)

    Raposo, F.; Borja, R.; Rincon, B. [Instituto de la Grasa (CSIC), Avda. Padre Garcia Tejero 4, 41012 Seville (Spain); Jimenez, A.M. [Departamento de Ciencias Ambientales, Universidad Pablo de Olavide, Ctra. De Utrera, km 1, 41013 Sevilla (Spain)

    2008-12-15

    A laboratory-scale study was conducted on the batch anaerobic digestion of sunflower oil cake (SuOC), solid waste derived from the extraction process of sunflower oil. A multi-reactor system was used to compare methane production from this waste at inoculum to substrate ratios (ISRs) of 3.0, 2.0, 1.5, 1.0, 0.8 and 0.5 (expressed as volatile solids (VS) basis). The tests were carried out at mesophilic temperature (35 C) and run against a control of inoculum without substrate. The results obtained in the biochemical methane potential (BMP) tests showed that the ultimate methane yield (Y{sub M,ult}) decreased considerably from 227{+-}23 to 107{+-}11 ml CH{sub 4} at standard temperature and pressure (STP) conditions g{sup -1} VS{sub added} when the ISR decreased from 3.0 to 0.5, showing a clear influence of the ISR on the methane yield coefficient. The biodegradability (BD) of the waste also decreased from 86% to 41% when the ISR varied from 3.0 to 0.5. A net total ammonia nitrogen (TAN) yield of 39.2 mg N g{sup -1} VS{sub added} was obtained, and this value was not influenced by the ISRs assayed, which demonstrated the appropriate operation of the hydrolytic-acidogenic stage of the overall digestion process. A clear imbalance of the methanogenic process was observed at the lowest ISRs studied (0.5 and 0.8) due to a considerable increase in CODs and TVFA in the digestates. The profile of VFA was also influenced by the ISR, typical of the proteinaceous substrates. (author)

  15. Conserving intertidal habitats: What is the potential of ecological engineering to mitigate impacts of coastal structures?

    Science.gov (United States)

    Perkins, Matthew J.; Ng, Terence P. T.; Dudgeon, David; Bonebrake, Timothy C.; Leung, Kenneth M. Y.

    2015-12-01

    and services, prohibits quantification of absolute and relative magnitudes of ecological impacts due to coastal structures or effectiveness of mitigation interventions. This knowledge deficit restricts evaluation of the potential of ecological engineering to contribute to conservation policies for intertidal habitats. To improve mitigation design and effectiveness, a greater focus on in-situ research is needed, requiring stronger and timely collaboration between government agencies, construction partners and research scientists.

  16. Research and development progresses in the mitigation and utilization of coal bed methane%煤层气治理与利用技术研究开发进展

    Institute of Scientific and Technical Information of China (English)

    李志凯; 秦张峰; 吴志伟; 赵建涛; 李树娜; 董梅; 樊卫斌; 王建国

    2013-01-01

    煤层气作为一种非常规天然气,既是宝贵的清洁能源,其主要成分甲烷同时也是一种主要的温室气体;煤层气的直接排放不仅加剧了大气温室效应和环境污染,同时也是能源资源的极大浪费.近年来,煤层气的治理和利用受到了广泛关注,有关技术研究和开发取得了很大进展.本文对近年来煤层气的治理和利用技术研发进展进行了总结和评估,侧重于介绍煤层气分离系统中关键的中、高浓度煤层气催化燃烧脱氧技术以及乏风瓦斯逆向流催化燃烧减排及余热利用技术.最后对煤层气综合利用技术进行了展望.%Coal bed methane (CBM) as an unconventional natural gas is a valuable energy resources;meanwhile the main content of CBM,methane,is also one of the most important gases that contribute towards inducing the greenhouse effect.The mitigation and utilization of coal bed methane,by reducing methane emissions and producing energy from recovered methane,can offer both opportunities to mitigate global climate change and to generate new sources of clean energy,which is therefore of great significance in both economic and environmental aspects and has received extensive attentions in recent years.In this paper,we attempt to make a review on the recent progresses of research and development in the mitigation and utilization of CBM.We focused mainly on the application of catalytic combustion in CBM mitigation and utilization,especially the deoxygenation of oxygen-bearing CBM,which is the key issue for methane concentration through pressure swing adsorption,as well as the mitigation and heat recovery of ventilation air methane (VAM) by using catalytic flow reversal reactor.Lastly,we would have an outlook on the possible technologies for the integrated utilization of CBM.

  17. Methane production potential of leachate generated from Korean food waste recycling facilities: a lab-scale study.

    Science.gov (United States)

    Lee, Dae Hee; Behera, Shishir Kumar; Kim, Ji Won; Park, Hung-Suck

    2009-02-01

    This paper examines the applicability of food waste leachate (FWL) in bioreactor landfills or anaerobic digesters to produce methane as a sustainable solution to the persisting leachate management problem in Korea. Taking into account the climatic conditions in Korea and FWL characteristics, the effect of key parameters, viz., temperature, alkalinity and salinity on methane yield was investigated. The monthly average moisture content and the ratio of volatile solids to total solids of the FWL were found to be 84% and 91%, respectively. The biochemical methane potential experiment under standard digestion conditions showed the methane yield of FWL to be 358 and 478 ml/g VS after 10 and 28 days of digestion, respectively, with an average methane content of 70%. Elemental analysis showed the chemical composition of FWL to be C(13.02)H(23.01)O(5.93)N(1). The highest methane yield of 403 ml/g VS was obtained at 35 degrees C due to the adaptation of seed microorganisms to mesophilic atmosphere, while methane yields at 25, 45 and 55 degrees C were 370, 351 and 275 ml/g VS, respectively, at the end of 20 days. Addition of alkalinity had a favorable effect on the methane yield. Dilution of FWL with salinity of 2g/l NaCl resulted in 561 ml CH(4)/g VS at the end of 30 days. Considering its high biodegradability (82.6%) and methane production potential, anaerobic digestion of FWL in bioreactor landfills or anaerobic digesters with a preferred control of alkalinity and salinity can be considered as a sustainable solution to the present emergent problem.

  18. Demand-side mitigation options of the agricultural sector: potential, barriers and ways forward

    Directory of Open Access Journals (Sweden)

    Brunelle Thierry

    2017-01-01

    Full Text Available This paper reviews the potential and barriers of demand-side mitigation options in the agricultural sector based on the recent academic literature and on a survey conducted on a sample of 788 respondents living in France. The mitigation potential of such measures as reducing losses in the food supply chain and shifting diets toward less animal products is estimated to be particularly high, higher, in particular, than supply-side mitigation options. However, to ensure that these measures do not entail a reduction in protein intake, these estimations should consider both caloric and protein units, and take into account the digestibility differentials between protein sources. Our survey shows that people are relatively reluctant to eat more sustainably, preferring to reduce their emissions in other areas such as housing or equipment. This relative reluctance is mainly due to individual perceptions linked to health concerns, taste or habits. Some obstacles could easily be overcome through well-designed policies aiming to, for example, advertise a lower consumption of red meat for health benefits. National governments are, however, rather inactive on this topic, leaving the initiative to the civil society.

  19. Assessing the Potential of Climate Change Mitigation Actions in Three Different City Types in Finland

    Directory of Open Access Journals (Sweden)

    Seppo Junnila

    2012-07-01

    Full Text Available As the effects of global warming have become more evident, ambitious short-term greenhouse gas emission reduction targets have been set in recent years. Many cities worldwide have adopted an active approach to climate change mitigation, but policy makers are not always knowledgeable of the true effects of their planned mitigation action. The purpose of this paper is to evaluate the effectiveness of different mitigation strategies in achieving low-carbon urban communities. The assessment is conducted via means of consumption based hybrid life-cycle assessment, which allows the reduction potential to be analyzed from the perspective of an individual resident of the urban community. The assessed actions represent strategies that are both adopted by the case cities and possible to implement with current best practices in Finland. The four assessed actions comprise: (1 dense urban structure with less private driving; (2 the use of energy production based on renewable sources; (3 new low-energy residential construction; and (4 improving the energy efficiency of existing buildings. The findings show that the effectiveness depends greatly on the type of city, although in absolute terms the most significant reduction potential lies with lowering the fossil fuel dependence of the local energy production.

  20. Compositional changes in swine manure fibers treated with aqueous ammonia soaking (AAS) resulting in increased methane potential

    DEFF Research Database (Denmark)

    Jurado, Esperanza; Hansen, Mads A.T.; Gavala, Hariklia N.;

    2013-01-01

    AAS treatment is a very efficient method to increase the methane potential of manure fibers. The chemical composition and supramolecular structures of swine manure fibers before and after AAS treatment was investigated in this study. Composition analyses, atomic force microscopy (AFM), scanning...... and accessible during subsequent anaerobic digestion. This finding has confirmed earlier experimental results, showing that delignification was not necessarily the limiting factor during conversion of manure fibers into methane while cellulose accessibility during digestion seemed more crucial....

  1. Forestry for mitigating the greenhouse effect : an ecological and economic assessment of the potential of land use to mitigate CO2 emissions in the Highlands of Chiapas, Mexico

    NARCIS (Netherlands)

    Jong, de B.H.J.

    2000-01-01

    The present study intends to answer some of the important questions that arise when translating projects that have an ecological potential to mitigate carbon excesses, into actual implementation of these projects in a farmer-dominated landscape. Farm and community forestry projects for greenhouse ga

  2. Forestry for mitigating the greenhouse effect : an ecological and economic assessment of the potential of land use to mitigate CO2 emissions in the Highlands of Chiapas, Mexico

    NARCIS (Netherlands)

    Jong, de B.H.J.

    2000-01-01

    The present study intends to answer some of the important questions that arise when translating projects that have an ecological potential to mitigate carbon excesses, into actual implementation of these projects in a farmer-dominated landscape. Farm and community forestry projects for

  3. Influence of lignin on biochemical methane potential of biomass for biogas production

    DEFF Research Database (Denmark)

    Triolo, J M; Sommer, S G; Møller, H B

    2011-01-01

    Biochemical methane potential (BMP) of biomass is of great importance in assessing biodegradability as well as predicting biogas yield for biogas production. Since the current BMP determination methods are costly and time-consuming, innovative techniques for predicting BMP are needed. The objective...... of this study was to examine the influence of fibrous fractions of biomass on BMP to develop an economical and easy-to-use predicting model of BMP, and hence the biodegradability of organic materials for biogas production. The model was developed either for energy crops or for animal manures, or as a combined...

  4. Anaerobic digestion of macroalgae: methane potentials, pre-treatment, inhibition and co-digestion

    DEFF Research Database (Denmark)

    Bangsø Nielsen, Henrik; Heiske, Stefan

    2011-01-01

    for Chaetomorpha linum and 340 ml g VS1 for Saccharina latissima following 34 days of incubation. With an organic content of 21.1% (1.5–2.8 times higher than the other algae) S. latissima seems very suitable for anaerobic digestion. However, the methane yields of U. lactuca, G. vermiculophylla and C. linum could...... be increased with 68%, 11% and 17%, respectively, by pretreatment with maceration. U. lactuca is often observed during ‘green tides’ in Europe and has a high cultivation potential at Nordic conditions. Therefore, U. lactuca was selected for further investigation and co-digested with cattle manure in a lab...

  5. Effect of pre-treatments on methane production potential of energy crops and crop residues

    Energy Technology Data Exchange (ETDEWEB)

    Lehtomaki, A.; Ronkainen; Rintala, J.A. [Jyvaskla Univ. (Finland). Dept. of Biological and Environmental Sciences; Viinikainen, T.A. [Jyvaskla Univ. (Finland). Dept. of Chemistry

    2004-07-01

    Energy crops, that is, crops grown specifically for energy purposes are an alternative to food production in areas with sufficient agricultural land. Crop residues are also a potential source of energy. The anaerobic digestion of solid materials is limited by hydrolysis of complex polymeric substances such as lignocellulose. The methane producing potential of ligno cellulosic material is to pretreat the substrate in order to break up the polymer chains to more easily accessible soluble compounds. In this study, three different substrates were used: sugar beet tops, grass hay, and straw of oats. Biological pretreatments were the following: enzyme treatment, composting, white-rot fungi treatment. Also, pretreatment in water was tried. Chemical pretreatments included peracetic acid treatment, and treatment with two different alkalis. Alkaline pretreatments of hay and sugar beet tops have the potential to improve the methane yield. For instance, the yield of grass hay was increased 15 per cent by one particular alkaline treatment. Straw did not respond to any of the treatments tried. 18 refs., 1 tab., 2 figs.

  6. Evaluation of feeds from tropical origin for in vitro methane production potential and rumen fermentation in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Pal, K.; Patra, A. K.; Sahoo, K.

    2015-07-01

    Enteric methane arising due to fermentation of feeds in the rumen contributes substantially to the greenhouse gas emissions. Thus, like evaluation of chemical composition and nutritive values of feeds, methane production potential of each feed should be determined. This experiment was conducted to evaluate several feeds for methane production potential and rumen fermentation using in vitro gas production technique so that low methane producing feeds could be utilized to feed ruminants. Protein- and energy-rich concentrates (n=11), cereal and grass forages (n=11), and different straws and shrubs (n=12), which are commonly fed to ruminants in India, were collected from a number of locations. Gas production kinetics, methane production, degradability and rumen fermentation greatly varied (p<0.01) among feeds depending upon the chemical composition. Methane production (mL/g of degraded organic matter) was lower (p<0.01) for concentrate than forages, and straws and shrubs. Among shrubs and straws, methane production was lower (p<0.01) for shrubs than straws. Methane production was correlated (p<0.05) with concentrations of crude protein (CP), ether extract and non-fibrous carbohydrate (NFC) negatively, and with neutral detergent (NDF) and acid detergent fiber (ADF) positively. Potential gas production was negatively correlated (p=0.04) with ADF, but positively (p<0.01) with NFC content. Rate of gas production and ammonia concentration were influenced by CP content positively (p<0.05), but by NDF and ADF negatively (p<0.05). Total volatile fatty acid concentration and organic matter degradability were correlated (p<0.05) positively with CP and NFC content, but negatively with NDF and ADF content. The results suggest that incorporation of concentrates and shrubs replacing straws and forages in the diets of ruminants may decrease. (Author)

  7. Potential for Application of Retroreflective Materials instead of Highly Reflective Materials for Urban Heat Island Mitigation

    Directory of Open Access Journals (Sweden)

    Jihui Yuan

    2016-01-01

    Full Text Available Research on urban heat island (UHI mitigation has been carried out globally. Several strategies have been proposed or developed to mitigate UHI, including highly reflective (HR envelopes of buildings, green roofs, urban vegetation, shading, heat sinks, and air-conditioning efficiency. Among these techniques, HR envelopes have been extensively studied as an effective method to mitigate the UHI effect by reducing energy consumption. However, because most of HR materials are diffusive, HR envelopes applied to vertical surfaces can reflect both onto roads and nearby buildings. Additionally, HR roofs cannot reflect all incoming solar radiation to the sky if there are high buildings around it. Thus, HR materials applied as building envelopes have a limited effect against the solar contribution to the UHI. In order to solve this problem, retroreflective (RR materials, which reflect the solar radiation back towards the source, have been studied and developed to be applied as building envelopes instead of HR materials. This paper summarizes several previous researches on HR envelopes and cool roofs and summarizes several current researches on RR materials. The potential for application of RR envelopes in cities is proposed with consideration of economic and environmental factors.

  8. Potential of condensed tannins for the reduction of emissions of enteric methane and their effect on ruminant productivity

    Directory of Open Access Journals (Sweden)

    AT Piñeiro-Vázquez

    2015-01-01

    Full Text Available Methane (CH4 gas is a by-product of anaerobic fermentation of carbohydrates in the rumen of ruminant species. Agriculture contributes with 47% of anthropogenic emissions of CH4, being the ruminants responsible for 39% of enteric emissions of CH4. This greenhouse gas (GHG has twenty-five times higher global warming potential than CO2 and represents a loss of up to 12% of the gross energy consumed by ruminants. The aim of this review is to describe the mechanisms of action of condensed tannins contained in foliage of trees and shrubs, and their effect on rumen microbes, as well as their potential for mitigation of CH4 emissions. The findings suggest that condensed tannins reduce protozoa population up to 79% and along with this, rumen methanogens are decreased by up to 33%. Condensed tannins bounded to proteins and polysaccharides of the ration form complexes which reduce digestibility of dry and organic matter and production of metabolic used by methanogens to reduce CO2 to CH4 In vitro studies suggest that condensed tannins may reduce rumen CH4 up to 63% in vitro and up to 58% in vivo. Additionally, incorporation of condensed tannins in the ration of ruminants might increase weight gain by 26%, maybe due to the increase in the flow of protein of low rumen degradability to the small intestine or to the reduction of energy losses as CH4 in the rumen. It is concluded that incorporation of condensed tannins in the ration of ruminants at 3-6% of dry matter concentrations can reduce CH4 emissions as well as to improve weight gain and milk yield of productive animals.

  9. Submarine methane hydrates - Potential fuel resource of the 21st century

    Digital Repository Service at National Institute of Oceanography (India)

    Desa, E.

    initiated to date, some interesting ideas have been conceived for the production of methane from hydrates and its transportation to shore. Apart from being an abundant fuel resource, methane hydrates are also a matter of concern, as destabilization of sub...

  10. Numerical model investigation for potential methane explosion and benzene vapor intrusion associated with high-ethanol blend releases.

    Science.gov (United States)

    Ma, Jie; Luo, Hong; Devaull, George E; Rixey, William G; Alvarez, Pedro J J

    2014-01-01

    Ethanol-blended fuel releases usually stimulate methanogenesis in the subsurface, which could pose an explosion risk if methane accumulates in a confined space above the ground where ignitable conditions exist. Ethanol-derived methane may also increase the vapor intrusion potential of toxic fuel hydrocarbons by stimulating the depletion of oxygen by methanotrophs, and thus inhibiting aerobic biodegradation of hydrocarbon vapors. To assess these processes, a three-dimensional numerical vapor intrusion model was used to simulate the degradation, migration, and intrusion pathway of methane and benzene under different site conditions. Simulations show that methane is unlikely to build up to pose an explosion hazard (5% v/v) if diffusion is the only mass transport mechanism through the deeper vadose zone. However, if methanogenic activity near the source zone is sufficiently high to cause advective gas transport, then the methane indoor concentration may exceed the flammable threshold under simulated conditions. During subsurface migration, methane biodegradation could consume soil oxygen that would otherwise be available to support hydrocarbon degradation, and increase the vapor intrusion potential for benzene. Vapor intrusion would also be exacerbated if methanogenic activity results in sufficiently high pressure to cause advective gas transport in the unsaturated zone. Overall, our simulations show that current approaches to manage the vapor intrusion risk for conventional fuel released might need to be modified when dealing with some high ethanol blend fuel (i.e., E20 up to E95) releases.

  11. Stimulation of methane oxidation potential and effects on vegetation growth by bottom ash addition in a landfill final evapotranspiration cover.

    Science.gov (United States)

    Kim, Gil Won; Ho, Adrian; Kim, Pil Joo; Kim, Sang Yoon

    2016-09-01

    The landfilling of municipal solid waste is a significant source of atmospheric methane (CH4), contributing up to 20% of total anthropogenic CH4 emissions. The evapotranspiration (ET) cover system, an alternative final cover system in waste landfills, has been considered to be a promising way to mitigate CH4 emissions, as well as to prevent water infiltration using vegetation on landfill cover soils. In our previous studies, bottom ash from coal-fired power plants was selected among several industrial residues (blast furnace slag, bottom ash, construction waste, steel manufacture slag, stone powder sludge, and waste gypsum) as the best additive for ET cover systems, with the highest mechanical performance achieved for a 35% (wtwt(-1)) bottom ash content in soil. In this study, to evaluate the field applicability of bottom ash mixed soil as ET cover, four sets of lysimeters (height 1.2m×width 2m×length 6m) were constructed in 2007, and four different treatments were installed: (i) soil+bottom ash (35% wtwt(-1)) (SB); (ii) soil+compost (2% wtwt(-1), approximately corresponding to 40Mgha(-1) in arable field scale) (SC); (iii) soil+bottom ash+compost (SBC); and (iv) soil only as the control (S). The effects of bottom ash mixing in ET cover soil on CH4 oxidation potential and vegetation growth were evaluated in a pilot ET cover system in the 5th year after installation by pilot experiments using the treatments. Our results showed that soil properties were significantly improved by bottom ash mixing, resulting in higher plant growth. Bottom ash addition significantly increased the CH4 oxidation potential of the ET cover soil, mainly due to improved organic matter and available copper concentration, enhancing methanotrophic abundances in soil amended with bottom ash. Conclusively, bottom ash could be a good alternative as a soil additive in the ET cover system to improve vegetation growth and mitigate CH4 emission impact in the waste landfill system. Copyright © 2016

  12. Concentration of field and skim latex by microfiltration - membrane fouling and biochemical methane potential of serum.

    Science.gov (United States)

    Thongmak, Narumol; Sridang, Porntip; Puetpaiboon, Udomphon; Grasmick, Alain

    2015-01-01

    Cross-flow microfiltration was used to concentrate field and skim latex suspensions and recover the smallest compounds (proteins, sugars, etc.) in permeate (serum solutions). The experiments were performed in a lab-scale microfiltration unit equipped with ceramic membranes. In continuous mode, the operations were performed at constant trans-membrane pressure (0.5 bars), constant cross-flow velocity (3 m/s) and constant temperature (28 ± 2°C). In retentate, the volumetric concentration factor was only close to 2 (about 54% of total solid content, TSC) when concentrating the field latex suspensions, and it reached 10 (close to 40% TSC) when concentrating skim latex suspensions. The quality of retentate suspensions let envisage a significant potential of industrial valorization. The membrane fouling rates appeared as an increasing function of dry rubber content suspension, and the main fouling origin (94%) was linked to a reversible accumulation of suspended compounds on the membrane surface. Permeate appeared as a clear yellow solution containing the smallest soluble organic fractions that show a high degree of biodegradability when using biochemical methane potential tests. The chemical oxygen demand (COD) removal was then higher than 92% and the methane production yield was close to 0.29 NLCH4/gCODremoved. The association of a membrane separation step and anaerobic digestion appeared, then, as a relevant solution to recover rubber content from skim latex suspensions and energy from the anaerobic digestion of serum.

  13. Anaerobic biodegradability of Category 2 animal by-products: methane potential and inoculum source.

    Science.gov (United States)

    Pozdniakova, Tatiana A; Costa, José C; Santos, Ricardo J; Alves, M M; Boaventura, Rui A R

    2012-11-01

    Category 2 animal by-products that need to be sterilized with steam pressure according Regulation (EC) 1774/2002 are studied. In this work, 2 sets of experiments were performed in mesophilic conditions: (i) biomethane potential determination testing 0.5%, 2.0% and 5.0% total solids (TS), using sludge from the anaerobic digester of a wastewater treatment plant as inoculum; (ii) biodegradability tests at a constant TS concentration of 2.0% and different inoculum sources (digested sludge from a wastewater treatment plant; granular sludge from an upflow anaerobic sludge blanket reactor; leachate from a municipal solid waste landfill; and sludge from the slaughterhouse wastewater treatment anaerobic lagoon) to select the more adapted inoculum to the substrate in study. The higher specific methane production was of 317 mL CH(4)g(-1) VS(substrate) for 2.0% TS. The digested sludge from the wastewater treatment plant led to the lowest lag-phase period and higher methane potential rate. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Methylotrophic methanogenic Thermoplasmata implicated in reduced methane emissions from bovine rumen

    DEFF Research Database (Denmark)

    Poulsen, Morten; Schwab, Clarissa; Jensen, Bent Borg

    2013-01-01

    Rumen methanogens are major sources of anthropogenic methane emissions, and these archaea are targets in strategies aimed at reducing methane emissions. Here we show that the poorly characterised Thermoplasmata archaea in bovine rumen are methylotrophic methanogens and that they are reduced upon...... potential as target in future strategies to mitigate methane emissions from ruminant livestock. Our findings and the findings of others also indicate a wider distribution of methanogens than previously anticipated....

  15. Estimating European soil organic carbon mitigation potential in a global integrated land use model

    Science.gov (United States)

    Frank, Stefan; Böttcher, Hannes; Schneider, Uwe; Schmid, Erwin; Havlík, Petr

    2013-04-01

    Several studies have shown the dynamic interaction between soil organic carbon (SOC) sequestration rates, soil management decisions and SOC levels. Management practices such as reduced and no-tillage, improved residue management and crop rotations as well as the conversion of marginal cropland to native vegetation or conversion of cultivated land to permanent grassland offer the potential to increase SOC content. Even though dynamic interactions are widely acknowledged in literature, they have not been implemented in most existing land use decision models. A major obstacle is the high data and computing requirements for an explicit representation of alternative land use sequences since a model has to be able to track all different management decision paths. To our knowledge no study accounted so far for SOC dynamics explicitly in a global integrated land use model. To overcome these conceptual difficulties described above we apply an approach capable of accounting for SOC dynamics in GLOBIOM (Global Biosphere Management Model), a global recursive dynamic partial equilibrium bottom-up model integrating the agricultural, bioenergy and forestry sectors. GLOBIOM represents all major land based sectors and therefore is able to account for direct and indirect effects of land use change as well as leakage effects (e.g. through trade) implicitly. Together with the detailed representation of technologies (e.g. tillage and fertilizer management systems), these characteristics make the model a highly valuable tool for assessing European SOC emissions and mitigation potential. Demand and international trade are represented in this version of the model at the level of 27 EU member states and 23 aggregated world regions outside Europe. Changes in the demand on the one side, and profitability of the different land based activities on the other side, are the major determinants of land use change in GLOBIOM. In this paper we estimate SOC emissions from cropland for the EU until

  16. Prospective use of bacteriocinogenic Pediococcus pentosaceus as direct-fed microbial having methane reducing potential

    Institute of Scientific and Technical Information of China (English)

    Sanjay Kumar; Sumit S Dagar; Seyed H Ebrahimi; Ravinder K Malik; Ramesh C Upadhyay; Anil K Puniya

    2015-01-01

    Direct-fed microbials (DFM), general y regarded as safe status, are successful y used in improving rumen ecology, gastro-in-testinal health, feed efifciency, milk production and growth rate in ruminants. On the other hand, methanogenesis in rumen, which accounts for a signiifcant loss of ruminant energy and increased greenhouse gas in environment, is of great concern, therefore, use of DFM for improving productivity without compromising the animal health and ecological sustainability is encouraged. The present study was conducted to investigate the methane reducing potential of bacteriocinogenic strain Pediococcus pentosaceus-34. Since, the culture showed no hemolysis on blood agar and DNase activity, hence, it was considered to be avirulent in nature, a prerequisite for any DFM. The culture also showed tolerance to pH 5.0 for 24 h with 0.5%organic acid mixture, whereas when given a shock for 2 h at different pH and organic acids concentrations, it showed growth at pH 3.0 and 4.0 with 0.1 and 1.0%organic acids, respectively, as having good animal probiotics attributes. The total gas production was signiifcantly (P<0.05) higher in live pedicoccal culture (LPC) and dead pedicoccal culture (DPC) both with wheat straw, when compared to the control. In sugarcane bagasse, gas production was signiifcantly lower (P<0.05) with LPC compared to the control and DPC both. Methane was reduced by the inclusion of LPC in sugarcane bagasse (0.07 mL CH4 mg–1 dry matter digestibility) with no effect on other rumen fermentation parameters. However, with wheat straw and LPC total gas, in vitro dry matter digestibility, total volatile fatty acids increased signiifcantly but no reduction in methane production was observed in comparison to the control. Therefore, further research is warranted in this direction, if the bacteriocinogenic strains can be used as DFM for ruminants to improve the ruminant productivity.

  17. The effect of coal bed dewatering and partial oxidation on biogenic methane potential

    Science.gov (United States)

    Jones, Elizabeth J.P.; Harris, Steve H.; Barnhart, Elliott P.; Orem, William H.; Clark, Arthur C.; Corum, Margo D.; Kirshtein, Julie D.; Varonka, Matthew S.; Voytek, Mary A.

    2013-01-01

    Coal formation dewatering at a site in the Powder River Basin was associated with enhanced potential for secondary biogenic methane determined by using a bioassay. We hypothesized that dewatering can stimulate microbial activity and increase the bioavailability of coal. We analyzed one dewatered and two water-saturated coals to examine possible ways in which dewatering influences coal bed natural gas biogenesis by looking at differences with respect to the native coal microbial community, coal-methane organic intermediates, and residual coal oxidation potential. Microbial biomass did not increase in response to dewatering. Small Subunit rRNA sequences retrieved from all coals sampled represented members from genera known to be aerobic, anaerobic and facultatively anaerobic. A Bray Curtis similarity analysis indicated that the microbial communities in water-saturated coals were more similar to each other than to the dewatered coal, suggesting an effect of dewatering. There was a higher incidence of long chain and volatile fatty acid intermediates in incubations of the dewatered coal compared to the water-saturated coals, and this could either be due to differences in microbial enzymatic activities or to chemical oxidation of the coal associated with O2 exposure. Dilute H2O2 treatment of two fractions of structural coal (kerogen and bitumen + kerogen) was used as a proxy for chemical oxidation by O2. The dewatered coal had a low residual oxidation potential compared to the water-saturated coals. Oxidation with 5% H2O2 did increase the bioavailability of structural coal, and the increase in residual oxidation potential in the water saturated coals was approximately equivalent to the higher methanogenic potential measured in the dewatered coal. Evidence from this study supports the idea that coal bed dewatering could stimulate biogenic methanogenesis through partial oxidation of the structural organics in coal once anaerobic conditions are restored.

  18. Potential methane production in thawing permafrost is constrained by methanogenic population size, carbon density, and substrate

    Science.gov (United States)

    Liebner, S.; Lehr, C.; Wagner, D.; Obu, J.; Lantuit, H.; Fritz, M.

    2016-12-01

    The release of carbon from newly thawed permafrost is estimated to add between 0.05 and 0.39 °C to the simulated global mean surface air temperature by the year 2300. The release of the potent greenhouse gas CH4 following permafrost thaw is thereby of particular concern. Models simulated a contribution of CH4 to the radiative forcing from thawing permafrost of up to 40% for the maximum extent of thermokarst (1). Batch experiments on thawed permafrost samples, however, have rendered the contribution of anaerobically produced carbon and in particular of CH4 to be surprisingly weak (2) and CH4 production which is realized through methanogenic archaea was reported to be low and associated with long lag phases . This leads to the hypotheses that initial methanogenic population sizes and/or substrates are limiting factors in permafrost. The objective of this study is to identify constraints for CH4 production in thawing permafrost. We analyzed several low Arctic permafrost cores of up to 3 m depth of different land cover types, sediment properties, age and stratigraphy for methanogenic abundance, potential methane production and predictors of both. We found that methanogenic population size and substrate pool are constraints on methane production but unlike expected, they do not fully explain low CH4 production rates in thawing permafrost. Even when both, population size and substrate concentrations, were large, the potential production of CH4 was still comparably low. Furthermore we show that the potential production of CH4 in thawing permafrost is a function of the methanogenic population size if substrate is not the limiting factor and that the methanogenic population size in turn is a function of the carbon density. Based on our study we propose that on the long term after permafrost has thawed, growth and community shifts within the methanogenic population will occur which potentially will increase methane production by orders of magnitude. 1. Schneider von

  19. The coalbed methane production potential method for optimization of wells location selection

    Institute of Scientific and Technical Information of China (English)

    Feng-Ke DOU; Yong-Shang KANG; Shao-Feng QIN; De-Lei MAO; Jun HAN

    2013-01-01

    A gas production potential method for optimization of gas wellsite locations selection is proposed in terms of the coalbed gas resources volume and the recoverability.The method uses the actual data about reservoirs in a coalbed gas field in central China to optimize wellsite locations in the studied area in combination with the dynamic data about actual production in the coalbed gas field,selects a favorable subarea for gas wells deployment.The method is established based on the basic properties of coal reservoirs,in combination with the coalbed thickness and the gas content to make an analysis of the gas storage potential of a coal reservoir,as well as resources volume and the permeability of a coal reservoir.This method can be popularized for optimization of wellsite locations in other methane gas development areas or blocks.

  20. Potential impact on climate of the exploitation of methane hydrate deposits offshore

    Digital Repository Service at National Institute of Oceanography (India)

    Glasby, G.P.

    –175 www.elsevier.com/locate/marpetgeo * Current address: 42 Warminster Cresent, Sheffield S8 9NW. E-mail address: g.p.glasby@talk21.com (G.P. Glasby). 2. Stability and occurrence of methane hydrates Methane hydrate has a clathrate structure in which..., it was concluded that the magnitude of the methane increases was insufficient to account for the extent of atmospheric warming and that about 50 Tg of methane per year (37 Mt of methane carbon) would have needed to be introduced into the atmosphere to account...

  1. Renewable energy technologies for the Indian power sector: mitigation potential and operational strategies

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, D. [Centre de Sciences Humaines, New Delhi (India); Shukla, P.R. [Indian Inst. of Management, Vastrapur, Ahmedabad (India); Garg, A. [Winrock International India, New Delhi (India); Ramana, P.V. [Winrock International, Arlington, VA (United States)

    2002-12-01

    The future economic development trajectory for India is likely to result in rapid and accelerated growth in energy demand, with attendant shortages and problems. Due to the predominance of fossil fuels in the generation mix, there are large negative environmental externalities caused by electricity generation. The power sector alone has a 40 percent contribution to the total carbon emissions. In this context, it is imperative to develop and promote alternative energy sources that can lead to sustainability of the energy-environment system. There are opportunities for renewable energy technologies under the new climate change regime as they meet the two basic conditions to be eligible for assistance under UNFCCC mechanisms: they contribute to global sustainability through GHG mitigation; and, they conform to national priorities by leading to the development of local capacities and infrastructure. This increases the importance of electricity generation from renewables. Considerable experience and capabilities exist in the country on renewable electricity technologies. But a number of techno-economic, market-related, and institutional barriers impede technology development and penetration. Although at present the contribution of renewable electricity is small, the capabilities promise the flexibility for responding to emerging economic, socio-environmental and sustainable development needs. This paper discusses the renewable and carbon market linkages and assesses mitigation potential of power sector renewable energy technologies under global environmental intervention scenarios for GHG emissions reduction. An overall energy system framework is used for assessing the future role of renewable energy in the power sector under baseline and different mitigation scenarios over a time frame of 35 years, between 2000 to 2035. The methodology uses an integrated bottom-up modelling framework. Looking into past performance trends and likely future developments, analysis results

  2. Assessment of potential greenhouse gas mitigation of available household solid waste treatment technologies

    Directory of Open Access Journals (Sweden)

    Hoang Minh Giang

    2013-11-01

    Full Text Available Current household solid waste treatment practices in most cities in Vietnam caused a great amount of direct greenhouse gas (GHG emissions. Available solid waste treatment technologies should be seriously taken  into consideration as a wedge of GHG mitigation in waste sector base on presently Vietnamese economic conditions. This study aim to evaluate the potential amount of GHG mitigation from current domestic solid waste treatment technologies in Vietnam including landfills and composting from various management scenarios. In oder to use Tier 2 model of IPCC 2006 for GHG estimation from landfills, an analysis on current household solid waste management system of the city was obtained by using material flow analysis approach. A case study in Hanoi, the capital city of Vietnam was carried out in this research. As a result, there was a reduced of over 70% of the amount of CH4 emissions and  up to 53% of total GHG saving (CO2-eq from avoiding organic waste to landfill. In addition, applying an energy recovery from LFG system to available landfills would lead to aproximately 75% of GHG saved compare to current emission of waste sector.Doi: http://dx.doi.org/10.12777/wastech.1.1.10-16Citation: Giang, H.M.,Luong, N.D., and Huong, L.T.M.2013. Assessment of potential greenhouse gas mitigation of available household solid waste treatment technologies. . Waste Technology 1(1:6-9. Doi: http://dx.doi.org/10.12777/wastech.1.1.10-16

  3. Potentials and costs of carbon dioxide mitigation in the world's buildings

    Energy Technology Data Exchange (ETDEWEB)

    Urge-Vorsatz, Diana [Department of Environmental Sciences and Policy, Central European University, Nador utca 9, H-1051 Budapest (Hungary)], E-mail: vorsatzd@ceu.hu; Novikova, Aleksandra [Department of Environmental Sciences and Policy, Central European University, Nador utca 9, H-1051 Budapest (Hungary)], E-mail: novikovaa@ceu.hu

    2008-02-15

    Buildings are responsible for over a third of global energy-related carbon dioxide (CO{sub 2}) emissions. A significant share of these emissions can be avoided cost effectively through improved energy efficiency, while providing the same or higher level of energy services. How large is this emission reduction potential globally and how much will it cost for society to unlock it? This paper provides answers to these questions, presenting the results of bottom-up research conducted for the Intergovernmental Panel on Climate Change (IPCC), based on the assessment of 80 country- or regional-level mitigation studies throughout the world. First, the paper analyses the findings of these studies in a common framework. Then, it aggregates their results into a global estimate of CO{sub 2} mitigation potential. The paper concludes that by 2020 it is possible to cut cost effectively approximately 29% of buildings-related global CO{sub 2} emissions, the largest among all sectors reported by the IPCC, representing a 3.2 GtCO{sub 2}eq. reduction. Developing countries house the largest cost-effective potential with up to 52% of building-level emissions, whereas transition economies and industrialised countries have cost-effective potentials of up to 37% and 25%, respectively. Energy-efficient lighting was identified as the most attractive measure worldwide, in terms of both reduction potential and cost effectiveness. If this potential is realised, the building-related CO{sub 2} emissions would stay constant over 2004-2030. These stabilisation levels (if achieved by all other sectors) would cancel about 3{sup o}C temperature increase over the projected period of time.

  4. Potentials and costs of carbon dioxide mitigation in the world's buildings

    Energy Technology Data Exchange (ETDEWEB)

    Uerge-Vorsatz, Diana; Novikova, Aleksandra [Department of Environmental Sciences and Policy, Central European University, Nador utca 9, H-1051 Budapest (Hungary)

    2008-02-15

    Buildings are responsible for over a third of global energy-related carbon dioxide (CO{sub 2}) emissions. A significant share of these emissions can be avoided cost effectively through improved energy efficiency, while providing the same or higher level of energy services. How large is this emission reduction potential globally and how much will it cost for society to unlock it? This paper provides answers to these questions, presenting the results of bottom-up research conducted for the Intergovernmental Panel on Climate Change (IPCC), based on the assessment of 80 country- or regional-level mitigation studies throughout the world. First, the paper analyses the findings of these studies in a common framework. Then, it aggregates their results into a global estimate of CO{sub 2} mitigation potential. The paper concludes that by 2020 it is possible to cut cost effectively approximately 29% of buildings-related global CO{sub 2} emissions, the largest among all sectors reported by the IPCC, representing a 3.2 GtCO{sub 2}eq. reduction. Developing countries house the largest cost-effective potential with up to 52% of building-level emissions, whereas transition economies and industrialised countries have cost-effective potentials of up to 37% and 25%, respectively. Energy-efficient lighting was identified as the most attractive measure worldwide, in terms of both reduction potential and cost effectiveness. If this potential is realised, the building-related CO{sub 2} emissions would stay constant over 2004-2030. These stabilisation levels (if achieved by all other sectors) would cancel about 3 C temperature increase over the projected period of time. (author)

  5. First fully ab initio potential energy surface of methane with a spectroscopic accuracy

    Science.gov (United States)

    Nikitin, A. V.; Rey, M.; Tyuterev, Vl. G.

    2016-09-01

    Full 9-dimensional ab initio potential energy surfaces for the methane molecule are constructed using extended electronic structure coupled-cluster calculations with various series of basis sets following increasing X cardinal numbers: cc-pVXZ (X = 3, 4, 5, 6), aug-cc-ACVXZ (X = 3, 4, 5), and cc-pCVXZ-F12 (X = 3, 4). High-order dynamic electron correlations including triple and quadrupole excitations as well as relativistic and diagonal Born-Oppenheimer breakdown corrections were accounted for. Analytical potential functions are parametrized as non-polynomial expansions in internal coordinates in irreducible tensor representation. Vibrational energy levels are reported using global variational nuclear motion calculations with exact kinetic energy operator and a full account of the tetrahedral symmetry of CH4. Our best ab initio surface including above-mentioned contributions provides the rms (obs.-calc.) errors of less than 0.11 cm-1 for vibrational band centers below 4700 cm-1, and ˜0.3 cm-1 for all 229 assigned experimentally determined vibrational levels up to the Icosad range <7900 cm-1 without empirically adjusted parameters. These results improve the accuracy of ab initio methane vibrational predictions by more than an order of magnitude with respect to previous works. This is an unprecedented accuracy of first-principles calculations of a five-atomic molecule for such a large data set. New ab initio potential results in significantly better band center predictions even in comparison with best available empirically corrected potential energy surfaces. The issues related to the basis set extrapolation and an additivity of various corrections at this level of accuracy are discussed.

  6. Determination of coalbed methane potential and gas adsorption capacity in Western Kentucky coals

    Science.gov (United States)

    Mardon, S.M.; Takacs, K.G.; Hower, J.C.; Eble, C.F.; Mastalerz, Maria

    2006-01-01

    The Illinois Basin has not been developed for Coalbed Methane (CBM) production. It is imperative to determine both gas content and other parameters for the Kentucky portion of the Illinois Basin if exploration is to progress and production is to occur in this area. This research is part of a larger project being conducted by the Kentucky Geological Survey to evaluate the CBM production of Pennsylvanian-age western Kentucky coals in Ohio, Webster, and Union counties using methane adsorption isotherms, direct gas desorption measurements, and chemical analyses of coal and gas. This research will investigate relationships between CBM potential and petrographic, surface area, pore size, and gas adsorption isotherm analyses of the coals. Maceral and reflectance analyses are being conducted at the Center for Applied Energy Research. At the Indiana Geological Survey, the surface area and pore size of the coals will be analyzed using a Micrometrics ASAP 2020, and the CO2 isotherm analyses will be conducted using a volumetric adsorption apparatus in a water temperature bath. The aforementioned analyses will be used to determine site specific correlations for the Kentucky part of the Illinois Basin. The data collected will be compared with previous work in the Illinois Basin and will be correlated with data and structural features in the basin. Gas composition and carbon and hydrogen isotopic data suggest mostly thermogenic origin of coalbed gas in coals from Webster and Union Counties, Kentucky, in contrast to the dominantly biogenic character of coalbed gas in Ohio County, Kentucky.

  7. Effect of dilution and ash supplement on the bio-methane potential of palm oil mill effluent (POME)

    Science.gov (United States)

    Jijai, Sunwanee; Muleng, Saina; Siripatana, Chairat

    2017-08-01

    This study aimed to evaluate the bio-methane potential of POME at different dilutions (100, 80, 60, 40, and 20 percent of initial POME) and different pH dues to different levels of ash supplement. Five different amounts of ash were added to digesters (0, 2, 4, 6, and 8 grams of ash were added to 170 ml of POME respectively). The digesters were operated in batch anaerobic digestion systems at room temperature (28-30 °C) and the experiments were performed in duplicate manner. The results showed that POME without dilution gave highest cumulative biogas (950 ml). However, 80% dilution from original POME gave the highest methane yield (45.83 mL CH4/ gCODadded or 103.13 mL CH4/ gCODremoved). Finally, the results of experiment 2, this adding ash into POME increased pH as well as enhanced the biogas production. It was found that adding ash at the ash:POME ratio of 2 g: 170 ml gave the highest both the cumulative biogas and methane yield (1,520 mL and 218.79 mL CH4/ gCODremoved respectively). The addition of ash in the raw waste of POME gave the pH in the range of criteria and highest bio-methane potential. The modified Gompertz equation, Schnute as well as Monod kinetic models were used to compare the data from the experiments. It was found that the factors that affected included, the bio-methane production and the kinetic parameters (the maximum specific methane production rates (Rm ml/day) and the methane production potential (P, mL)), initial COD, nutrients, levels of dilution, and initial pH (by adding different level of ash). However, λ (lag phase period) was not affected by initial COD and other factors. While Monod kinetics provides valuable insight in explaining what could happen behind the systematic trends.

  8. In vitro evaluation of different varieties of maize fodder for their methane generation potential and digestibility with goat rumen liquor

    Directory of Open Access Journals (Sweden)

    Shalini Vaswani

    2016-11-01

    Full Text Available Aim: To evaluate the methane generation potential and digestibility of different (normal and three high-quality protein maize [HQPM] varieties of maize fodder with goat rumen liquor in vitro. Materials and Methods: Methane production potential and digestibility of different varieties of maize fodder were tested in in vitro gas production test. Seven varieties of maize, four normal (HTHM 5101, DHM 117, HM 5, and Shaktiman/900 M Gold, and three high-quality protein (HQPM 5, HQPM 7, and HQPM 9/Vivek were grown in different plots under the same environmental and agro-climatic conditions. Fodders were harvested at 45-50 days of sowing, and the representative samples of fodder from different varieties of maize were collected for analysis. Dried and grinded form of these maize fodder varieties was tested for gas, methane, and digestibility using goat rumen microflora in in vitro gas syringes. Results: Gas production (ml/g dry matter [DM] was highest for HM5 variety (97.66, whereas lowest for HQPM 9 variety (64.22. Gas production (ml/g degraded DM [DDM] and methane (% were statistically similar in different varieties of maize fodder. The methane production expressed as ml/g DM and ml/g DDM was significantly (p<0.05 highest for HM 5 (14.22 and 26.62 and lowest for DHM 117 variety (7.47 and 14.13. The in vitro DM digestibility (% and in vitro organic matter digestibility (% varied from 47.48 (HQPM 5 to 52.05 (HQPM 9 and 50.03 (HQPM 7 to 54.22 (HM 5, respectively. Conclusion: The present study concluded that DHM 117 maize variety fodder has lowest methane generation potential and incorporating it in the dietary regime of ruminants may contribute to lower methane production.

  9. Global typology of urban energy use and potentials for an urbanization mitigation wedge

    Science.gov (United States)

    Creutzig, Felix; Baiocchi, Giovanni; Bierkandt, Robert; Pichler, Peter-Paul; Seto, Karen C.

    2015-01-01

    The aggregate potential for urban mitigation of global climate change is insufficiently understood. Our analysis, using a dataset of 274 cities representing all city sizes and regions worldwide, demonstrates that economic activity, transport costs, geographic factors, and urban form explain 37% of urban direct energy use and 88% of urban transport energy use. If current trends in urban expansion continue, urban energy use will increase more than threefold, from 240 EJ in 2005 to 730 EJ in 2050. Our model shows that urban planning and transport policies can limit the future increase in urban energy use to 540 EJ in 2050 and contribute to mitigating climate change. However, effective policies for reducing urban greenhouse gas emissions differ with city type. The results show that, for affluent and mature cities, higher gasoline prices combined with compact urban form can result in savings in both residential and transport energy use. In contrast, for developing-country cities with emerging or nascent infrastructures, compact urban form, and transport planning can encourage higher population densities and subsequently avoid lock-in of high carbon emission patterns for travel. The results underscore a significant potential urbanization wedge for reducing energy use in rapidly urbanizing Asia, Africa, and the Middle East. PMID:25583508

  10. Climate change mitigation: the potential of agriculture as a renewable energy source in Nigeria.

    Science.gov (United States)

    Elum, Z A; Modise, D M; Nhamo, G

    2017-02-01

    Energy is pivotal to the economic development of every nation. However, its production and utilization leads to undesirable carbon emissions that aggravate global warming which results in climate change. The agriculture sector is a significant user of energy. However, it has the potential to be a major contributor to Nigeria's energy supply mix in meeting its energy deficit. More so, in the light of current and impending adverse effects of climate change, there is a need to contain GHG's emissions. This paper focuses on bioenergy utilization as a climate change mitigation strategy and one that can, through effective waste management, enhance sustainable economic development in Nigeria. The paper employed a critical discourse analysis to examine the potential of the agricultural sector to provide biofuels from energy crops and other biomass sources. We conclude that Nigeria can reduce its GHG emissions and greatly contribute to global climate change mitigation while also alleviating its energy supply deficit if the agricultural and municipal wastes readily available in its towns and cities are converted to bioenergy. Such engagements will not only promote a clean and healthy environment but also create jobs for economic empowerment and a better standard of living for the people.

  11. Ozonation and Thermal Pre-Treatment of Municipal Sewage Sludge-Implications for Toxicity and Methane Potential

    DEFF Research Database (Denmark)

    Davidsson, A.; Eriksson, Eva; Fick, J.

    2013-01-01

    The aim of this study was to determine effects on methane potential and overall sludge quality from two different sludge pre-treatment technologies (ozonation high/low dosage and thermal treatment 55/70 degrees C). In general both treatments produced increased methane potential. Thermal treatment...... resulted in higher chemical oxygen demand (COD)-solubilisation, while the highest volatile fatty acids (VFA) increase was obtained with ozonation. Sludges had inhibiting effects in a barley seed germination assay and a yeast oestrogen screen both before and after pre-treatment, but inhibition was reduced...... by ozone treatment and digestion. No statistical significant reduction in concentrations of included pharmaceuticals could be observed....

  12. Effectiveness of Space Debris Mitigation Guidelines: Economic Potential of LEO and Traffic Management Issues

    Science.gov (United States)

    Belviso, Luciano

    Space debris probably represent one of the major issues for the future development and exploitation of space by all spacefaring nations. Considering the large range of possible mitigation techniques, some general criteria to evaluate them shall be taken into account: cost, effectiveness, technical and legal applicability in order to assess their effectiveness. Even though the Inter Agency Space Debris Coordination Committee (IADC) guidelines are considered as the basis for a new regulatory regime of mitigation, the problem concerning the legal instrument by which the international community would accept these guidelines remains still unsolved. In this paper, we will focus on the following issues: Economic potential of orbital regions. Since the international community lacks consensus to conclude a legally binding instrument, a voluntary adherence regime seems a possible way to apply mitigation measures. However, with mitigation efforts having only small effects into the future, expenditures are not easy to be justified today even if they could reduce the economic consequences of debris in the long period[1]. Some orbital regions, such as the Geostationary Orbit, are already the subject of international agreements, however, the properties of other regions of near-earth space are also distinct as far as their potential economic value is concerned[2]. Therefore, the applicability of mitigation techniques on the basis of cost-benefit analysis will be considered in this paper. Applicability of satellites traffic control. For satellites in Low Earth Orbit, the main hazard is posed by other object located in narrow sets of altitudes and inclinations[4]. Satellites control systems usually allow only a limited number of operation mostly related to small trajectory corrections and they can result not sufficient to avoid collisions with debris. That is why a complementary approach is required although this could represent an additional cost. In this paper we will consider the

  13. Potential problems with environmental sound barriers when used in mitigating surface transportation noise.

    Science.gov (United States)

    Arenas, Jorge P

    2008-11-01

    The public, increasingly well-informed about the problem of excessive noise, is taking actions for the development of new transport infrastructure projects and improvement of existing infrastructure. In addition, many countries have implemented mandatory Environmental Impact Assessment procedures. As a result, the construction of sound barriers has become a common measure, which can be used by an agency to mitigate potentially significant noise impacts. A sound barrier, eventually, will become part of the surrounding landscape and could be a cause of impact for ecosystems, the road users and those who live alongside the road. Basically, this article discusses these potential effects in the context of environmental assessment procedures. In addition, results of a pilot survey conducted at a residential area affected by the construction of a barrier are presented. Although most residents felt that sleeping conditions improved after the barrier was built, most important negative reactions are the loss of sunlight and visual impact.

  14. Methanotrophy potential versus methane supply by pore water diffusion in peatlands

    Science.gov (United States)

    Hornibrook, E. R. C.; Bowes, H. L.; Culbert, A.; Gallego-Sala, A. V.

    2009-08-01

    Low affinity methanotrophic bacteria consume a significant quantity of methane in wetland soils in the vicinity of plant roots and at the oxic-anoxic interface. Estimates of the efficiency of methanotrophy in peat soils vary widely in part because of differences in approaches employed to quantify methane cycling. High resolution profiles of dissolved methane abundance measured during the summer of 2003 were used to quantity rates of upward methane flux in four peatlands situated in Wales, UK. Aerobic incubations of peat from a minerotrophic and an ombrotrophic mire were used to determine depth distributions of kinetic parameters associated with methane oxidation. The capacity for methanotrophy in a 3 cm thick zone immediately beneath the depth of nil methane abundance in pore water was significantly greater than the rate of upward diffusion of methane in all four peatlands. Rates of methane diffusion in pore water at the minerotrophic peatlands were small (consume entirely methane transported by pore water diffusion in the four peatlands with the exception of 4 of the 33 gas profiles sampled. Flux rates to the atmosphere regardless are high because of gas transport through vascular plants, in particular, at the minerotrophic sites. Cumulative rainfall amount 3-days prior to sampling correlated well with the distance between the water table level and the depth of 0 μmol l-1 methane, indicating that precipitation events can impact methane distributions in pore water. Further work is needed to characterise the kinetics of methane oxidation spatially and temporally in different wetland types in order to determine generalized relationships for methanotrophy in peatlands that can be incorporated into process-based models of methane cycling in peat soils.

  15. Marine and Hydrokinetic Renewable Energy Technologies: Potential Navigational Impacts and Mitigation Measures

    Energy Technology Data Exchange (ETDEWEB)

    Cool, Richard, M.; Hudon, Thomas, J.; Basco, David, R.; Rondorf, Neil, E.

    2009-12-10

    On April 15, 2008, the Department of Energy (DOE) issued a Funding Opportunity Announcement for Advanced Water Power Projects which included a Topic Area for Marine and Hydrokinetic Renewable Energy Market Acceleration Projects. Within this Topic Area, DOE identified potential navigational impacts of marine and hydrokinetic renewable energy technologies and measures to prevent adverse impacts on navigation as a sub-topic area. DOE defines marine and hydrokinetic technologies as those capable of utilizing one or more of the following resource categories for energy generation: ocean waves; tides or ocean currents; free flowing water in rivers or streams; and energy generation from the differentials in ocean temperature. PCCI was awarded Cooperative Agreement DE-FC36-08GO18177 from the DOE to identify the potential navigational impacts and mitigation measures for marine hydrokinetic technologies, as summarized herein. The contract also required cooperation with the U.S. Coast Guard (USCG) and two recipients of awards (Pacific Energy Ventures and reVision) in a sub-topic area to develop a protocol to identify streamlined, best-siting practices. Over the period of this contract, PCCI and our sub-consultants, David Basco, Ph.D., and Neil Rondorf of Science Applications International Corporation, met with USCG headquarters personnel, with U.S. Army Corps of Engineers headquarters and regional personnel, with U.S. Navy regional personnel and other ocean users in order to develop an understanding of existing practices for the identification of navigational impacts that might occur during construction, operation, maintenance, and decommissioning. At these same meetings, “standard” and potential mitigation measures were discussed so that guidance could be prepared for project developers. Concurrently, PCCI reviewed navigation guidance published by the USCG and international community. This report summarizes the results of this effort, provides guidance in the form of a

  16. A highly accurate {\\it ab initio} potential energy surface for methane

    CERN Document Server

    Owens, Alec; Yachmenev, Andrey; Tennyson, Jonathan; Thiel, Walter

    2016-01-01

    A new nine-dimensional potential energy surface (PES) for methane has been generated using state-of-the-art \\textit{ab initio} theory. The PES is based on explicitly correlated coupled cluster calculations with extrapolation to the complete basis set limit and incorporates a range of higher-level additive energy corrections. These include: core-valence electron correlation, higher-order coupled cluster terms beyond perturbative triples, scalar relativistic effects and the diagonal Born-Oppenheimer correction. Sub-wavenumber accuracy is achieved for the majority of experimentally known vibrational energy levels with the four fundamentals of $^{12}$CH$_4$ reproduced with a root-mean-square error of $0.70{\\,}$cm$^{-1}$. The computed \\textit{ab initio} equilibrium C{--}H bond length is in excellent agreement with previous values despite pure rotational energies displaying minor systematic errors as $J$ (rotational excitation) increases. It is shown that these errors can be significantly reduced by adjusting the e...

  17. Estimation of Coal Bed Methane Potential of Coal Seams of Margherita Coal Field, Assam, India

    Directory of Open Access Journals (Sweden)

    Prasenjit Talukdar

    2015-06-01

    Full Text Available The rapid industrialization and growing energy needs have put a great stress on the conventional energy resources. This is even more concerning for a country like India which is a net importer of oil. To meet the ever increasing need for energy, it is essential that the search for unconventional energy is intensified. This paper deals with the estimation of coal bed methane potential of the Margherita Coal Field of Assam, India. For this purpose, eight coal samples were collected from Tirap O.C.P., Ledo UG Incline and Tikak O.C.P collieries of the Margherita coal field. Proximate analysis, megascopic study and finally qualitative analysis of these eight samples was undertaken. After analysis, the inferred reserves of CBM at Margherita Coalfield, was found to be in the range of 42.5-49.04 Billion Cubic Meter.

  18. Bio-energy retains its mitigation potential under elevated CO2.

    Directory of Open Access Journals (Sweden)

    Marion Liberloo

    Full Text Available BACKGROUND: If biofuels are to be a viable substitute for fossil fuels, it is essential that they retain their potential to mitigate climate change under future atmospheric conditions. Elevated atmospheric CO2 concentration [CO2] stimulates plant biomass production; however, the beneficial effects of increased production may be offset by higher energy costs in crop management. METHODOLOGY/MAIN FINDINGS: We maintained full size poplar short rotation coppice (SRC systems under both current ambient and future elevated [CO2] (550 ppm and estimated their net energy and greenhouse gas balance. We show that a poplar SRC system is energy efficient and produces more energy than required for coppice management. Even more, elevated [CO2] will increase the net energy production and greenhouse gas balance of a SRC system with 18%. Managing the trees in shorter rotation cycles (i.e., 2 year cycles instead of 3 year cycles will further enhance the benefits from elevated [CO2] on both the net energy and greenhouse gas balance. CONCLUSIONS/SIGNIFICANCE: Adapting coppice management to the future atmospheric [CO2] is necessary to fully benefit from the climate mitigation potential of bio-energy systems. Further, a future increase in potential biomass production due to elevated [CO2] outweighs the increased production costs resulting in a northward extension of the area where SRC is greenhouse gas neutral. Currently, the main part of the European terrestrial carbon sink is found in forest biomass and attributed to harvesting less than the annual growth in wood. Because SRC is intensively managed, with a higher turnover in wood production than conventional forest, northward expansion of SRC is likely to erode the European terrestrial carbon sink.

  19. Bio-energy retains its mitigation potential under elevated CO2.

    Science.gov (United States)

    Liberloo, Marion; Luyssaert, Sebastiaan; Bellassen, Valentin; Njakou Djomo, Sylvestre; Lukac, Martin; Calfapietra, Carlo; Janssens, Ivan A; Hoosbeek, Marcel R; Viovy, Nicolas; Churkina, Galina; Scarascia-Mugnozza, Giuseppe; Ceulemans, Reinhart

    2010-07-19

    If biofuels are to be a viable substitute for fossil fuels, it is essential that they retain their potential to mitigate climate change under future atmospheric conditions. Elevated atmospheric CO2 concentration [CO2] stimulates plant biomass production; however, the beneficial effects of increased production may be offset by higher energy costs in crop management. We maintained full size poplar short rotation coppice (SRC) systems under both current ambient and future elevated [CO2] (550 ppm) and estimated their net energy and greenhouse gas balance. We show that a poplar SRC system is energy efficient and produces more energy than required for coppice management. Even more, elevated [CO2] will increase the net energy production and greenhouse gas balance of a SRC system with 18%. Managing the trees in shorter rotation cycles (i.e., 2 year cycles instead of 3 year cycles) will further enhance the benefits from elevated [CO2] on both the net energy and greenhouse gas balance. Adapting coppice management to the future atmospheric [CO2] is necessary to fully benefit from the climate mitigation potential of bio-energy systems. Further, a future increase in potential biomass production due to elevated [CO2] outweighs the increased production costs resulting in a northward extension of the area where SRC is greenhouse gas neutral. Currently, the main part of the European terrestrial carbon sink is found in forest biomass and attributed to harvesting less than the annual growth in wood. Because SRC is intensively managed, with a higher turnover in wood production than conventional forest, northward expansion of SRC is likely to erode the European terrestrial carbon sink.

  20. Tidal wetland conservation and restoration for flood mitigation in estuaries and deltas: examples and global potential

    Science.gov (United States)

    Temmerman, Stijn; Smolders, Sven; Stark, Jeroen; meire, patrick

    2014-05-01

    Low-lying and densely populated deltas and estuaries are world widely exposed to flood risks caused by storm surges. On the one hand, global change is increasing these flood risks through accelerating sea level rise and increasing storm intensity, but on the other hand, local-scale human impacts on deltas and estuaries are in many cases even more increasing the vulnerability to floods. Here we address the degradation and reclamation of tidal wetlands (i.e. salt marshes in the temperate zone and mangroves in the tropical zone) as a major source for increasing vulnerability to flooding of estuaries and deltas. Firstly, we present examples of flood mitigation by tidal wetland conservation and restoration, and secondly we explore the potentials and limitations for global application of this approach of ecosystem-based flood defense (see Temmerman et al. 2013). First, we use the Scheldt estuary (SW Netherlands and Belgium) as an example where historic wetland reclamation has importantly contributed to increasing flood risks, and where tidal marsh restoration on the previously reclaimed land is nowadays brought into large-scale practice as an essential part of the flood defense system. Based on data and hydrodynamic modelling, we show that large-scale historic marsh reclamation has largely reduced the water storage capacity of the estuary and has reduced the friction to propagating flood waves, resulting in an important landward increase of tidal and storm surge levels. Hydrodynamic model scenarios demonstrate how tidal and storm surge propagation through the estuary are affected by tidal marsh properties, including the surface area, elevation, vegetation and position of marshes along the estuary. We show that nowadays tidal wetland creation on previously reclaimed land is applied as an essential part of the flood defense system along the Scheldt estuary. Secondly, a global analysis is presented of the potential application of tidal wetlands in flood mitigation in

  1. [Preliminary assessment of the potential of biochar technology in mitigating the greenhouse effect in China].

    Science.gov (United States)

    Jiang, Zhi-Xiang; Zheng, Hao; Li, Feng-Min; Wang, Zhen-Yu

    2013-06-01

    The production of biochar by pyrolysis and its application to soil can sequester the CO2 which was absorbed by plants from atmosphere into soil, in addition it can also bring multiple benefits for agriculture production. On the basis of the available potential survey of the biomass residues from agriculture and forestry section, life cycle assessment was employed to quantify the potential of biochar technology in mitigation of greenhouse gases in our country. The results showed: In China, the amount of available biomass resource was 6.04 x 10(8) t every year and its net greenhouse effect potential was 5.32 x 10(8) t CO(2e) (CO(2e): CO2 equivalent), which was equivalent to 0.88 t CO(2e) for every ton biomass. The greatest of contributor to the total potential was plant carbon sequestration in soil as the form of biochar which accounts for 73.94%, followed by production of renewable energy and its percentage was 23.85%. In summary, production of biochar from agriculture and forestry biomass residues had a significant potential for our country to struggle with the pressure of greenhouse gas emission.

  2. Potential methane emission from north-temperate lakes following ice melt

    Science.gov (United States)

    Michmerhuizen, C.M.; Striegl, R.G.; McDonald, M.E.

    1996-01-01

    Methane, a radiatively active 'greenhouse' gas, is emitted from lakes to the atmosphere throughout the open-water season. However, annual lake CH4 emissions calculated solely from open-water measurements that exclude the time of spring ice melt may substantially underestimate the lake CH4 source strength. We estimated potential spring CH4 emission at the time of ice melt for 19 lakes in northern Minnesota and Wisconsin. Lakes ranged in area from 2.7 to 57,300 ha and varied in littoral zone sediment type. Regression analyses indicated that lake area explained 38% of the variance in potential CH4 emission for relatively undisturbed lakes; as lake area increases potential CH4 emission per unit area decreases. Inclusion of a second term accounting for the presence or absence of soft organic-rich littoral-zone sediments explained 83% of the variance in potential spring CH4 emission. Total estimated spring CH4 emission for 1993 for all Minnesota lakes north of 45?? with areas ???4 ha was 1.5 x 108 mol CH4 assuming a 1 : 1 ratio of soft littoral sediment to hard littoral sediment lakes. Emission estimates ranged from 5.3 x 107 tool assuming no lakes have soft organic-rich littoral sediments to 4.5 x 108 mol assuming all lakes have soft organic-rich littoral sediments. This spring CH4 pulse may make up as much as 40% of the CH4 annually emitted to the atmosphere by small lakes.

  3. Reduced greenhouse gas mitigation potential of no-tillage soils through earthworm activity.

    Science.gov (United States)

    Lubbers, Ingrid M; van Groenigen, Kees Jan; Brussaard, Lijbert; van Groenigen, Jan Willem

    2015-09-04

    Concerns about rising greenhouse gas (GHG) concentrations have spurred the promotion of no-tillage practices as a means to stimulate carbon storage and reduce CO2 emissions in agro-ecosystems. Recent research has ignited debate about the effect of earthworms on the GHG balance of soil. It is unclear how earthworms interact with soil management practices, making long-term predictions on their effect in agro-ecosystems problematic. Here we show, in a unique two-year experiment, that earthworm presence increases the combined cumulative emissions of CO2 and N2O from a simulated no-tillage (NT) system to the same level as a simulated conventional tillage (CT) system. We found no evidence for increased soil C storage in the presence of earthworms. Because NT agriculture stimulates earthworm presence, our results identify a possible biological pathway for the limited potential of no-tillage soils with respect to GHG mitigation.

  4. Environmental potentials of policy instruments to mitigate nutrient emissions in Chinese livestock production.

    Science.gov (United States)

    Zheng, Chaohui; Liu, Yi; Bluemling, Bettina; Mol, Arthur P J; Chen, Jining

    2015-01-01

    To minimize negative environmental impact of livestock production, policy-makers face a challenge to design and implement more effective policy instruments for livestock farmers at different scales. This research builds an assessment framework on the basis of an agent-based model, named ANEM, to explore nutrient mitigation potentials of five policy instruments, using pig production in Zhongjiang county, southwest China, as the empirical filling. The effects of different policy scenarios are simulated and compared using four indicators and differentiating between small, medium and large scale pig farms. Technology standards, biogas subsidies and information provisioning prove to be the most effective policies, while pollution fees and manure markets fail to environmentally improve manure management in pig livestock farming. Medium-scale farms are the more relevant scale category for a more environmentally sound development of Chinese livestock production. A number of policy recommendations are formulated as conclusion, as well as some limitations and prospects of the simulations are discussed.

  5. Exploiting the full potential of photometric quasar surveys: Optimal power spectra through blind mitigation of systematics

    CERN Document Server

    Leistedt, Boris

    2014-01-01

    We present optimal measurements of the angular power spectrum of the XDQSOz catalogue of photometric quasars from the Sloan Digital Sky Survey. These measurements rely on a quadratic maximum likelihood estimator that simultaneously measures the auto- and cross-power spectra of four redshift samples, and provides minimum-variance, unbiased estimates even at the largest angular scales. Since photometric quasars are known to be strongly affected by systematics such as spatially-varying depth and stellar contamination, we introduce a new framework of extended mode projection to robustly mitigate the impact of systematics on the power spectrum measurements. This technique involves constructing template maps of potential systematics, decorrelating them on the sky, and projecting out modes which are significantly correlated with the data. Our method is able to simultaneously process several thousands of nonlinearly-correlated systematics, and mode projection is performed in a blind fashion. Using our final power spe...

  6. Quantifying climate change mitigation potential in Great Plains wetlands for three greenhouse gas emission scenarios

    Science.gov (United States)

    Byrd, Kristin B.; Ratliff, Jamie L.; Wein, Anne; Bliss, Norman B.; Sleeter, Benjamin M.; Sohl, Terry L.; Li, Zhengpeng

    2015-01-01

    We examined opportunities for avoided loss of wetland carbon stocks in the Great Plains of the United States in the context of future agricultural expansion through analysis of land-use land-cover (LULC) change scenarios, baseline carbon datasets and biogeochemical model outputs. A wetland map that classifies wetlands according to carbon pools was created to describe future patterns of carbon loss and potential carbon savings. Wetland avoided loss scenarios, superimposed upon LULC change scenarios, quantified carbon stocks preserved under criteria of carbon densities or land value plus cropland suitability. Up to 3420 km2 of wetlands may be lost in the region by 2050, mainly due to conversion of herbaceous wetlands in the Temperate Prairies where soil organic carbon (SOC) is highest. SOC loss would be approximately 0.20 ± 0.15 megagrams of carbon per hectare per year (MgC ha−1 yr−1), depending upon tillage practices on converted wetlands, and total ecosystem carbon loss in woody wetlands would be approximately 0.81 ± 0.41 MgC ha−1 yr−1, based on biogeochemical model results. Among wetlands vulnerable to conversion, wetlands in the Northern Glaciated Plains and Lake Agassiz Plains ecoregions exhibit very high mean SOC and on average, relatively low land values, potentially creating economically competitive opportunities for avoided carbon loss. This mitigation scenarios approach may be adapted by managers using their own preferred criteria to select sites that best meet their objectives. Results can help prioritize field-based assessments, where site-level investigations of carbon stocks, land value, and consideration of local priorities for climate change mitigation programs are needed.

  7. Potential of tannin-rich plants, Leucaena leucocephala, Glyricidia sepium and Manihot esculenta, to reduce enteric methane emissions in sheep.

    Science.gov (United States)

    Archimède, H; Rira, M; Barde, D J; Labirin, F; Marie-Magdeleine, C; Calif, B; Periacarpin, F; Fleury, J; Rochette, Y; Morgavi, D P; Doreau, M

    2016-12-01

    An in vivo trial was conducted in sheep to investigate the effect of three tropical tannin-rich plants (TRP) on methane emission, intake and digestibility. The TRP used were leaves of Glyricidia sepium, Leucaena leucocephala and Manihot esculenta that contained, respectively, 39, 75 and 92 g condensed tannins/kg DM. Methane was determined with the sulphur hexafluoride tracer technique. Eight rumen-cannulated sheep of two breeds (four Texel, four Blackbelly) were used in two 4 × 4 Latin square designs. Four experimental diets were tested. They consisted in a tropical natural grassland hay based on Dichanthium spp. fed alone (C) or in association with G. sepium (G), L. leucocephala (L) or M. esculenta (M) given as pellets at 44% of the daily ration. Daily organic matter intake was higher in TRP diets (686, 984, 1054 and 1186 g/day for C, G, L and M respectively; p  0.05). Methane emission was 47.1, 44.9, 33.3 and 33.5 g/kg digestible organic matter intake for C, G, L and M, respectively, and was significantly lower (p < 0.05) for L and M than for G and C. Our results confirm the potential of some TRP to reduce methane production. The strong decrease in methane and the increase in intake with TRPs may be due to their presentation as pellets.

  8. Evaluation of coal bed methane potential of coal seams of Sawang Colliery, Jharkhand, India

    Indian Academy of Sciences (India)

    Anil M Pophare; Vinod A Mendhe; A Varade

    2008-04-01

    The coal seams of Sawang Colliery, East Bokaro Coalfields are bituminous to sub-bituminous in nature and categorized as high gaseous seams (degree II to degree III level). These seams have the potential for coal bed methane (CBM) and their maturity increases with increasing depth, as a result of enhanced pressure-temperature conditions in the underground. The vitrinite maceral group composition of the investigated coal seams ranges from 62.50-83.15%, whereas the inertinite content varies from 14.93-36.81%. The liptinite content varies from 0.66% to 3.09%. The maximum micro-pores are confined within the vitrinite group of macerals. The coal seams exhibit vitrinite reflectance values (Ro% calculated) from 0.94% (sample CG-97) to 1.21% (sample CG-119). Proximate analyses of the investigated coal samples reveal that the moisture content (M%) ranges from 1.28% to 2.98%, whereas, volatile matter (VM%) content is placed in the range of 27.01% to 33.86%. The ash content (A%) ranges from 10.92% to 30.01%. Fixed carbon (FC%) content varies from 41.53% to 55.93%. Fuel ratio variation shows a restricted range from 1.53 to 1.97. All the coal samples were found to be strongly caking and forming coke buttons. The present study is based on the adsorption isotherm experiments carried out under controlled P-T conditions for determination of actual gas adsorption capacity of the coal seams. This analysis shows that the maximum methane gas adsorbed in the coal sample CG-81 is 17m3/t (Std. daf), at maximum pressure of 5.92MPa and experimental temperature of 30°C. The calculated Langmuir regression parameters PL and VL range from 2.49 to 3.75MPa and 22.94 to 26.88m3/t (Std. daf), respectively.

  9. Mitigating impact of thermal and rectified radio-frequency sheath potentials on edge localized modes

    Energy Technology Data Exchange (ETDEWEB)

    Gui, B. [Institute of Plasma Physics Chinese Academy of Sciences, Hefei (China); Lawerence Livermore National Lab, Livermore, California 94550 (United States); Xu, X. Q. [Lawerence Livermore National Lab, Livermore, California 94550 (United States); Myra, J. R.; D' Ippolito, D. A. [Lodestar Research Corporation, Boulder, Colorado 80301 (United States)

    2014-11-15

    The mitigating impact of thermal and rectified radio frequency (RF) sheath potentials on the peeling-ballooning modes is studied non-linearly by employing a two-fluid three-field simulation model based on the BOUT++ framework. Additional shear flow and the Kelvin-Helmholtz effect due to the thermal and rectified RF sheath potential are induced. It is found that the shear flow increases the growth rate while the K-H effect decreases the growth rate slightly when there is a density gradient, but the energy loss of these cases is suppressed in the nonlinear phase. The stronger external electrostatic field due to the sheaths has a more significant effect on the energy loss suppression. From this study, it is found the growth rate in the linear phase mainly determines the onset of edge-localized modes, while the mode spectrum width in the nonlinear phase has an important impact on the turbulent transport. The wider mode spectrum leads to weaker turbulent transport and results in a smaller energy loss. Due to the thermal sheath and rectified RF sheath potential in the scrape-off-layer, the modified shear flow tears apart the peeling-ballooning filament and makes the mode spectrum wider, resulting in less energy loss. The perturbed electric potential and the parallel current near the sheath region is also suppressed locally due to the sheath boundary condition.

  10. Mitigation of Intergranular Stress Corrosion Cracking in Al-Mg by Electrochemical Potential Control

    Science.gov (United States)

    McMahon, M. E.; Scully, J. R.; Burns, J. T.

    2017-08-01

    Intergranular stress corrosion cracking in the Al-Mg alloy AA5456-H116 is suppressed via cathodic polarization in 0.6 M NaCl, saturated (5.45 M) NaCl, 2 M MgCl2, and saturated (5 M) MgCl2. Three zones of intergranular stress corrosion cracking (IG-SCC) susceptibility correlate with pitting potentials of unsensitized AA5456-H116 and pure β phase (Al3Mg2) in each solution. These critical potentials reasonably describe the influence of α Al matrix and β phase dissolution rates on IG-SCC severity. Complete inhibition occurred at applied potentials of -1.0 V and -1.1 V versus saturated calomel electrode ( V SCE) in 0.6 M NaCl. Whereas only partial mitigation of IG-SCC was achieved at -0.9 V SCE in 0.6 M NaCl and at -0.9, -1.0, and -1.1 V SCE in the more aggressive environments. Correlation of pitting potentials in bulk environments with IG-SCC behavior suggests an effect of bulk environment [Cl-] and pH on the stabilized crack tip chemistry.

  11. GEOLOGIC SCREENING CRITERIA FOR SEQUESTRATION OF CO2 IN COAL: QUANTIFYING POTENTIAL OF THE BLACK WARRIOR COALBED METHANE FAIRWAY, ALABAMA

    Energy Technology Data Exchange (ETDEWEB)

    Jack C. Pashin; Richard E. Carroll; Richard H. Groshong Jr.; Dorothy E. Raymond; Marcella McIntyre; J. Wayne Payton

    2004-01-01

    Sequestration of CO{sub 2} in coal has potential benefits for reducing greenhouse gas emissions from the highly industrialized Carboniferous coal basins of North America and Europe and for enhancing coalbed methane recovery. Hence, enhanced coalbed methane recovery operations provide a basis for a market-based environmental solution in which the cost of sequestration is offset by the production and sale of natural gas. The Black Warrior foreland basin of west-central Alabama contains the only mature coalbed methane production fairway in eastern North America, and data from this basin provide an excellent basis for quantifying the carbon sequestration potential of coal and for identifying the geologic screening criteria required to select sites for the demonstration and commercialization of carbon sequestration technology. Coalbed methane reservoirs in the upper Pottsville Formation of the Black Warrior basin are extremely heterogeneous, and this heterogeneity must be considered to screen areas for the application of CO{sub 2} sequestration and enhanced coalbed methane recovery technology. Major screening factors include stratigraphy, geologic structure, geothermics, hydrogeology, coal quality, sorption capacity, technology, and infrastructure. Applying the screening model to the Black Warrior basin indicates that geologic structure, water chemistry, and the distribution of coal mines and reserves are the principal determinants of where CO{sub 2} can be sequestered. By comparison, coal thickness, temperature-pressure conditions, and coal quality are the key determinants of sequestration capacity and unswept coalbed methane resources. Results of this investigation indicate that the potential for CO{sub 2} sequestration and enhanced coalbed methane recovery in the Black Warrior basin is substantial and can result in significant reduction of greenhouse gas emissions while increasing natural gas reserves. Coal-fired power plants serving the Black Warrior basin in

  12. Potential for CO2 sequestration and enhanced coalbed methane production in the Netherlands

    NARCIS (Netherlands)

    Hamelinck, C.N.; Schreurs, H.; Faaij, A.P.C.; Ruijg, G.J.; Jansen, Daan; Pagnier, H.; Bergen, F. van; Wolf, K.-H.; Barzandji, O.; Bruining, H.

    2006-01-01

    This study investigated the technical and economic feasibility of using CO2 for the enhanced production of coal bed methane (ECBM) in the Netherlands. This concept could lead to both CO2 storage by adsorbing CO2 in deep coal layers that are not suitable for mining, as well as production of methane.

  13. Potential for CO2 sequestration and enhanced coalbed methane production in the Netherlands

    NARCIS (Netherlands)

    Hamelinck, C.N.; Schreurs, H.; Faaij, A.P.C.; Ruijg, G.J.; Jansen, Daan; Pagnier, H.; Bergen, F. van; Wolf, K.-H.; Barzandji, O.; Bruining, H.

    2006-01-01

    This study investigated the technical and economic feasibility of using CO2 for the enhanced production of coal bed methane (ECBM) in the Netherlands. This concept could lead to both CO2 storage by adsorbing CO2 in deep coal layers that are not suitable for mining, as well as production of methane.

  14. Mitigation potential and global health impacts from emissions pricing of food commodities

    Science.gov (United States)

    Springmann, Marco; Mason-D'Croz, Daniel; Robinson, Sherman; Wiebe, Keith; Godfray, H. Charles J.; Rayner, Mike; Scarborough, Peter

    2017-01-01

    The projected rise in food-related greenhouse gas emissions could seriously impede efforts to limit global warming to acceptable levels. Despite that, food production and consumption have long been excluded from climate policies, in part due to concerns about the potential impact on food security. Using a coupled agriculture and health modelling framework, we show that the global climate change mitigation potential of emissions pricing of food commodities could be substantial, and that levying greenhouse gas taxes on food commodities could, if appropriately designed, be a health-promoting climate policy in high-income countries, as well as in most low- and middle-income countries. Sparing food groups known to be beneficial for health from taxation, selectively compensating for income losses associated with tax-related price increases, and using a portion of tax revenues for health promotion are potential policy options that could help avert most of the negative health impacts experienced by vulnerable groups, whilst still promoting changes towards diets which are more environmentally sustainable.

  15. Identifying potential ground movement as a landslide mitigation approach using resistivity method

    Science.gov (United States)

    Izzati, F. N.; Laksmana, Z. S.; Marcelina, B.; Hutabarat, S. S.; Widodo

    2017-07-01

    Landslide is defined as a form of ground movement in which land mass suddenly fails downward on a slope as aresult of gravitational pull. One of the mitigative approaches into investigating landslide is to identify a potential slip zone usingresistivity method. In this study, the array chosen to acquire the resistivity data was Wenner array as it provides a robust resolution in mapping lateral resistivity variations. This method will generate a contour map portraying thedistribution of resistivity values of the subsurface. Beforehand, a 2-dimensional forward modeling was conducted to acquire anexpected ideal result of possible potential slip zone. Landslides itself are affiliated with a low resistivity zone that is locatedbetween two high resistivity zones. This study is conducted in a ground slump in Jalan Citra Green, Northern Bandung which is comprised of mostly unconsolidated soil. By applying a least-square inversion to the resistivity data obtained, resistivity values of 10-200 Ωm is attained. Based on the inversion result, a low resistivity zone of 10-20 Ωm is identified spanning from the surface to approximately 10 meters deep. In conclusion, furtherinvestigations are needed to determine whether the low resistivity zone is associated with potential slip zone as our datais limited to a single line

  16. Acting Globally: Potential Carbon Emissions Mitigation Impacts from an International Standards and Labelling Program

    Energy Technology Data Exchange (ETDEWEB)

    McNeil, Michael A; Letschert, Virginie E.; de la Rue du Can, Stephane; Egan, Christine

    2009-05-29

    This paper presents an analysis of the potential impacts of an international initiative designed to support and promote the development and implementation of appliances standards and labelling programs throughout the world. As part of previous research efforts, LBNL developed the Bottom Up Energy Analysis System (BUENAS), an analysis framework that estimates impact potentials of energy efficiency policies on a global scale. In this paper, we apply this framework to an initiative that would result in the successful implementation of programs focused on high priority regions and product types, thus evaluating the potential impacts of such an initiative in terms of electricity savings and carbon mitigation in 2030. In order to model the likely parameters of such a program, we limit impacts to a five year period starting in 2009, but assume that the first 5 years of a program will result in implementation of 'best practice' minimum efficiency performance standards by 2014. The 'high priority' regions considered are: Brazil, China, the European Union,India, Mexico and the United States. The products considered are: refrigerators, air conditioners, lighting (both fluorescent and incandescent), standby power (for consumer electronics) and televisions in the residential sector, and air conditioning and lighting in commercial buildings. In 2020, these regions and enduses account for about 37percent of global residential electricity and 29percent of electricity in commercial buildings. We find that 850Mt of CO2 could be saved in buildings by 2030 compared to the baseline forecast.

  17. Potential for Climate Change Mitigation in Degraded Forests: A Study from La Primavera, México

    Directory of Open Access Journals (Sweden)

    Arturo Balderas Torres

    2013-11-01

    Full Text Available Forests contribute to climate change mitigation by removing atmospheric carbon dioxide and storing it in biomass and other carbon pools. Additionally, since appropriate forest management can reduce emissions from deforestation and forest degradation, it is important to estimate the magnitude of these services to include them into climate policy. We used a forest inventory stratified by canopy cover in the oak-pine forest of La Primavera Biosphere Reserve in México (30,500 ha, to assess the potential provision of forest carbon services. Inventory results were used in combination with a Landsat image to estimate carbon stocks in arboreal biomass. Potential carbon removals were calculated from published allometric equations and models estimating tree growth rates, for enhancements in forested areas and for reforestation/afforestation. Carbon stocks estimated in arboreal biomass at the time of the inventory were 4.16 MtCO2eq (3.42–4.89. The potential for further carbon sequestration and enhancement could take the level of stocks up to 9.77 MtCO2eq (7.66–11.89, 95% confidence interval; previous fires have degraded carbon stocks below their natural potential. The results present a gradient of carbon stocks for different degradation levels and are consistent with national and international estimates and previous local research. The baseline for the estimation of reduced emissions is critical for assessing the overall contribution of forests to mitigate climate change. The local baseline of emissions might be around 1% according to historical data; however, when enhancements and reduced emissions are valuated together, a baseline of 3.7% is required to prevent the creation of perverse incentives favouring previously degraded areas; considering these figures for reduced emissions, the yearly carbon services provided by La Primavera, including enhancements, sequestration and reduced emissions, could be between 169.4 ktCO2eq/year (134.8–204.5 and

  18. Microbiology and potential applications of aerobic methane oxidation coupled to denitrification (AME-D) process: A review.

    Science.gov (United States)

    Zhu, Jing; Wang, Qian; Yuan, Mengdong; Tan, Giin-Yu Amy; Sun, Faqian; Wang, Cheng; Wu, Weixiang; Lee, Po-Heng

    2016-03-01

    Aerobic methane oxidation coupled to denitrification (AME-D) is an important link between the global methane and nitrogen cycles. This mini-review updates discoveries regarding aerobic methanotrophs and denitrifiers, as a prelude to spotlight the microbial mechanism and the potential applications of AME-D. Until recently, AME-D was thought to be accomplished by a microbial consortium where denitrifying bacteria utilize carbon intermediates, which are excreted by aerobic methanotrophs, as energy and carbon sources. Potential carbon intermediates include methanol, citrate and acetate. This mini-review presents microbial thermodynamic estimations and postulates that methanol is the ideal electron donor for denitrification, and may serve as a trophic link between methanotrophic bacteria and denitrifiers. More excitingly, new discoveries have revealed that AME-D is not only confined to the conventional synergism between methanotrophic bacteria and denitrifiers. Specifically, an obligate aerobic methanotrophic bacterium, Methylomonas denitrificans FJG1, has been demonstrated to couple partial denitrification with methane oxidation, under hypoxia conditions, releasing nitrous oxide as a terminal product. This finding not only substantially advances the understanding of AME-D mechanism, but also implies an important but unknown role of aerobic methanotrophs in global climate change through their influence on both the methane and nitrogen cycles in ecosystems. Hence, further investigation on AME-D microbiology and mechanism is essential to better understand global climate issues and to develop niche biotechnological solutions. This mini-review also presents traditional microbial techniques, such as pure cultivation and stable isotope probing, and powerful microbial techniques, such as (meta-) genomics and (meta-) transcriptomics, for deciphering linked methane oxidation and denitrification. Although AME-D has immense potential for nitrogen removal from wastewater, drinking

  19. Toxic Compounds in Our Food: Arsenic Uptake By Rice and Potential Mitigation By Silicon

    Science.gov (United States)

    Seyfferth, A.; Gill, R.; Penido, E.

    2014-12-01

    Arsenic is a ubiquitous element in soils worldwide and has the potential to negatively impact human and ecosystem health under certain biogeochemical conditions. While arsenic is relatively immobile in most oxidized soils due to a high affinity for soil solids, arsenic becomes mobilized under reduced soil conditions due to the reductive dissolution of iron(III) oxides thereby releasing soil-bound arsenic. Since arsenic is a well-known carcinogen, this plant-soil process has the potential to negatively impact the lives of billions of rice consumers worldwide upon plant uptake and grain storage of released arsenic. Moreover, arsenic uptake by rice is excacerbated by the use of As-laden groundwater for rice irrigation. One proposed strategy to decrease arsenic uptake by rice plants is via an increase in dissolved silicon in paddy soil solution (pore-water), since silicic acid and arsenous acid share an uptake pathway. However, several soil processes that influence arsenic cycling may be affected by silicon including desorption from bulk soil, formation and mineralogy of iron(III) oxide plaque, and adsorption/desorption onto/from iron plaque; the effect of silicon on these soil processes will ultimately dictate the effectiveness of altered dissolved silicon in decreasing arsenic uptake at the root, which in turn dictates the concentration of arsenic found in grains. Furthermore, the source of silicon may impact carbon cycling and, in particular, methane emissions. Here, impacts of altered dissolved silicon on processes that affect rhizospheric biogeochemical cycling of arsenic and subsequent plant-uptake, and how it influences other biogeochemical cycles such as carbon and iron are investigated. We show that silicon can decrease arsenic uptake and grain storage under certain conditions, and that altered silicon affects the type of iron (III) oxide that comprises iron plaque.

  20. Greenhouse gas mitigation in agriculture.

    Science.gov (United States)

    Smith, Pete; Martino, Daniel; Cai, Zucong; Gwary, Daniel; Janzen, Henry; Kumar, Pushpam; McCarl, Bruce; Ogle, Stephen; O'Mara, Frank; Rice, Charles; Scholes, Bob; Sirotenko, Oleg; Howden, Mark; McAllister, Tim; Pan, Genxing; Romanenkov, Vladimir; Schneider, Uwe; Towprayoon, Sirintornthep; Wattenbach, Martin; Smith, Jo

    2008-02-27

    Agricultural lands occupy 37% of the earth's land surface. Agriculture accounts for 52 and 84% of global anthropogenic methane and nitrous oxide emissions. Agricultural soils may also act as a sink or source for CO2, but the net flux is small. Many agricultural practices can potentially mitigate greenhouse gas (GHG) emissions, the most prominent of which are improved cropland and grazing land management and restoration of degraded lands and cultivated organic soils. Lower, but still significant mitigation potential is provided by water and rice management, set-aside, land use change and agroforestry, livestock management and manure management. The global technical mitigation potential from agriculture (excluding fossil fuel offsets from biomass) by 2030, considering all gases, is estimated to be approximately 5500-6000Mt CO2-eq.yr-1, with economic potentials of approximately 1500-1600, 2500-2700 and 4000-4300Mt CO2-eq.yr-1 at carbon prices of up to 20, up to 50 and up to 100 US$ t CO2-eq.-1, respectively. In addition, GHG emissions could be reduced by substitution of fossil fuels for energy production by agricultural feedstocks (e.g. crop residues, dung and dedicated energy crops). The economic mitigation potential of biomass energy from agriculture is estimated to be 640, 2240 and 16 000Mt CO2-eq.yr-1 at 0-20, 0-50 and 0-100 US$ t CO2-eq.-1, respectively.

  1. Soils as a Solution: The Potential of Rangelands to Contribute to Climate Change Mitigation

    Science.gov (United States)

    Silver, W. L.; Ryals, R.; DeLonge, M. S.; Owen, J. J.

    2015-12-01

    The majority of soil-related climate change research has focused on describing the problem - estimating rates of carbon (C) losses and greenhouse gas (GHG) emissions from natural and managed ecosystems. More research is needed to explore potential solutions to climate change through mitigation and adaptation. Here we report on an integrated set of studies aimed at critically evaluating the biogeochemical potential of rangeland soils to help mitigate climate change, while improving the sustainability and productivity of food production systems. We explored direct effects through enhanced net primary production (NPP) and soil C sequestration, and indirect effects through diversion of high emitting sources to lower emitting organic matter dynamics. We used a combination of long- and short-term field experiments, modeling, laboratory assays, life cycle assessment (LCA), and meta-analyses in consultation with a diverse group of stakeholders from both the private and public sectors. We found that organic matter amendments held particularly strong potential. Compost amendments increased soil C storage by 0.5-1.0 Mg C ha-1 y-1 in surface soils over 5 y, and increased NPP and water holding capacity. We measured 1.0 Mg of new C ha-1 y-1 over 3 y. Long-term amendment of cattle manure increased surface soil C by 19.0±7.3 Mg C ha-1 relative to unmanured fields. However, field and modeling experiments suggested that manure amendments lead to large nitrous oxide emissions that eventually eliminated CO2e benefits, whereas compost amendments continued to benefit climate for decades longer. An LCA identified a broader range of climate impacts. When scaled to an area of 25% of California's rangelands, new C sequestered following compost amendments (21 million Mg CO2e) exceeded emissions from cattle (15 million Mg CO2e); diverting organics from waste streams to amendments led to additional GHG savings. In collaboration with our partners, our research contributed to the development of

  2. The potential role for management of U.S. public lands in greenhouse gas mitigation and climate policy.

    Science.gov (United States)

    Olander, Lydia P; Cooley, David M; Galik, Christopher S

    2012-03-01

    Management of forests, rangelands, and wetlands on public lands, including the restoration of degraded lands, has the potential to increase carbon sequestration or reduce greenhouse gas (GHG) emissions beyond what is occurring today. In this paper we discuss several policy options for increasing GHG mitigation on public lands. These range from an extension of current policy by generating supplemental mitigation on public lands in an effort to meet national emissions reduction goals, to full participation in an offsets market by allowing GHG mitigation on public lands to be sold as offsets either by the overseeing agency or by private contractors. To help place these policy options in context, we briefly review the literature on GHG mitigation and public lands to examine the potential for enhanced mitigation on federal and state public lands in the United States. This potential will be tempered by consideration of the tradeoffs with other uses of public lands, the needs for climate change adaptation, and the effects on other ecosystem services.

  3. Geology and coal bed methane resource potential of the Gondwana Barapukuria Coal Basin, Dinajpur, Bangladesh

    Energy Technology Data Exchange (ETDEWEB)

    Islam, Md. Rafiqul; Hayashi, Daigoro [Department of Physics and Earth Sciences Faculty of Science, University of the Ryukyus, Okinawa, 903-0213 (Japan)

    2008-08-05

    constrained by adverse seam gradients and the presence of the overlying water-bearing Tertiary Dupi Tila sediments. The potential of coal bed methane extraction has been investigated as an alternative to underground mining. The study considers the Barapukuria deposit in terms of its geological structure, geothermal gradient, and the rank, porosity and permeability of the coal seams as determined by several phases of exploration of the area. The methane content of the bituminous coal at Barapukuria varies within the range 6.51-12.68 m{sup 3}/t, representing a potential resource of more than 5 Gm{sup 3} of gas. (author)

  4. GEOLOGIC SCREENING CRITERIA FOR SEQUESTRATION OF CO2 IN COAL: QUANTIFYING POTENTIAL OF THE BLACK WARRIOR COALBED METHANE FAIRWAY, ALABAMA

    Energy Technology Data Exchange (ETDEWEB)

    Jack C. Pashin; Richard E. Carroll; Richard H. Groshong, Jr.; Dorothy E. Raymond; Marcella McIntyre; J. Wayne Payton

    2003-01-01

    Sequestration of CO{sub 2} in coal has potential to reduce greenhouse gas emissions from coal-fired power plants while enhancing coalbed methane recovery. Data from more than 4,000 coalbed methane wells in the Black Warrior basin of Alabama provide an opportunity to quantify the carbon sequestration potential of coal and to develop a geologic screening model for the application of carbon sequestration technology. This report summarizes stratigraphy and sedimentation, structural geology, geothermics, hydrology, coal quality, gas capacity, and production characteristics of coal in the Black Warrior coalbed methane fairway and the implications of geology for carbon sequestration and enhanced coalbed methane recovery. Coal in the Black Warrior basin is distributed among several fluvial-deltaic coal zones in the Lower Pennsylvanian Pottsville Formation. Most coal zones contain one to three coal beds that are significant targets for coalbed methane production and carbon sequestration, and net coal thickness generally increases southeastward. Pottsville strata have effectively no matrix permeability to water, so virtually all flow is through natural fractures. Faults and folds influence the abundance and openness of fractures and, hence, the performance of coalbed methane wells. Water chemistry in the Pottsville Formation ranges from fresh to saline, and zones with TDS content lower than 10,000 mg/L can be classified as USDW. An aquifer exemption facilitating enhanced recovery in USDW can be obtained where TDS content is higher than 3,000 mg/L. Carbon dioxide becomes a supercritical fluid above a temperature of 88 F and a pressure of 1,074 psi. Reservoir temperature exceeds 88 F in much of the study area. Hydrostatic pressure gradients range from normal to extremely underpressured. A large area of underpressure is developed around closely spaced longwall coal mines, and areas of natural underpressure are distributed among the coalbed methane fields. The mobility and

  5. Energy strategy and mitigation potential in energy sector of the Russian federation

    Energy Technology Data Exchange (ETDEWEB)

    Yakovlev, A.F.; Petrov, V.N.; Chupyatov, V.P.

    1996-12-31

    This paper describes the mitigation potential in the Russian energy sector and presents CO{sub 2} - emission scenarios. Based on the Russian energy strategy, energy conservation potential has been estimated and three groups of energy conservation measures have been pointed out. Taking into account the economic development scenarios and the scenarios of energy consumption and energy conservation, future CO{sub 2} emission scenarios for 2000 and 2010 have been prepared. Some important characteristics of these scenarios have been presented and discussed. For the period 2000-2010 annual growth rates for CO{sub 2} emission in the Russian energy sector will not exceed 0.9-1.3 %, and emission levels in 2000 make up - 75-78 %, and in 2010 - 81-88 % of the 1990 level. For the probable scenario the CO{sub 2} emission reducing will make up about 6% and 25% (for the optimistic scenario about 16% and 31%) of CO{sub 2} emission for reference scenario in 2000 and 2010 respectively. Additional CO{sub 2} emission reducing (3-5% of domestic CO{sub 2} emission) will result from increasing share of natural gas consumption.

  6. Ontario Hydro experience in the identification and mitigation of potential failures in safety critical software systems

    Energy Technology Data Exchange (ETDEWEB)

    Huget, R.G.; Viola, M.; Froebel, P.A. [Ontario Hydro, Toronto, Ontario (Canada)

    1995-08-01

    Ontario Hydro has had experience in designing and qualifying safety critical software used in the reactor shutdown systems of its nuclear generating stations. During software design, an analysis of system level hazards and potential hardware failure effects provide input to determining what safeguards will be needed. One form of safeguard, called software self checks, continually monitor the health of the computer on line. The design of self checks usually is a trade off between the amount of computing resources required, the software complexity, and the level of safeguarding provided. As part of the software verification activity, a software hazards analysis is performed, which identifiers any failure modes that could lead to the software causing an unsafe state, and which recommends changes to mitigate that potential. These recommendations may involve a re-structuring of the software to be more resistant to failure, or the introduction of other safeguarding measures. This paper discusses how Ontario Hydro has implemented these aspects of software design and verification into safety critical software used in reactor shutdown systems.

  7. Sound management may sequester methane in grazed rangeland ecosystems

    Science.gov (United States)

    Considering their contribution to global warming, the sources and sinks of methane (CH4) should be accounted when undertaking a greenhouse gas inventory for grazed rangeland ecosystems. The aim of this study was to evaluate the mitigation potential of current ecological management programs implement...

  8. Carbon mitigation potential and costs of forestry options in Brazil, China, India, Indonesia, Mexico, the Philippines and Tanzania

    Energy Technology Data Exchange (ETDEWEB)

    Sathaye, J.; Makundi, W.; Andrasko, K.; Boer, R.; Ravindranath, N.; Sudha, P.; Rao, S.; Lasco, R.; Pulhin, F.; Masera, O.; Ceron, A.; Ordonez, J.; Deying, X.; Zhang, X.; Zuomin, S.

    2001-01-01

    This paper summarizes studies of carbon (C) mitigation potential and costs of about 40 forestry options in seven developing countries. Each study uses the same methodological approach - Comprehensive Mitigation Assessment Process (COMAP) - to estimate the above parameters between 2000 and 2030. The approach requires the projection of baseline and mitigation land-use scenarios. Coupled with data on a per ha basis on C sequestration or avoidance, and costs and benefits, it allows the estimation of monetary benefit per Mg C, and the total costs and carbon potential. The results show that about half (3.0 Pg C) the cumulative mitigation potential of 6.2 Petagram (Pg) C between 2000 and 2030 in the seven countries (about 200 x 106 Mg C yr-1) could be achieved at a negative cost and the remainder at costs ranging up to $100 Mg C-1. About 5 Pg C could be achieved, at a cost less than $20 per Mg C. Negative cost potential indicates that non-carbon revenue is sufficient to offset direct costs of these options. The achievable potential is likely to be smaller, however, due to market, institutional, and sociocultural barriers that can delay or prevent the implementation of the analyzed options.

  9. Effect of different steam explosion conditions on methane potential and enzymatic saccharification of birch.

    Science.gov (United States)

    Vivekanand, Vivekanand; Olsen, Elisabeth F; Eijsink, Vincent G H; Horn, Svein J

    2013-01-01

    Birch (Betula pubescens) was steam exploded at 13 different conditions with temperatures ranging from 170 to 230 °C and residence times ranging from 5 to 15 min. Increasing severity in the pretreatment led to degradation of xylan and formation of pseudo-lignin. The effect of the pretreatments was evaluated by running enzymatic saccharification and anaerobic digestion followed by analysis of sugar and methane yields, respectively. Enzymatically released glucose increased with pretreatment severity up to 220 °C for 10 min and levels of solubilized glucose reached 97% of the theoretical maximum. The highest methane yield (369 mL gVS(-1)) was obtained at a severity factor of 4.5 and this yield was 1.8 times higher than the yield from untreated birch. Enzymatic glucose yields and methane yields were generally correlated. The results indicate that steam-exploded birch can be effectively converted to either glucose or methane.

  10. Exploring the potential of fungi for methane abatement: Performance evaluation of a fungal-bacterial biofilter.

    Science.gov (United States)

    Lebrero, Raquel; López, Juan Carlos; Lehtinen, Iiro; Pérez, Rebeca; Quijano, Guillermo; Muñoz, Raúl

    2016-02-01

    Despite several fungal strains have been retrieved from methane-containing environments, the actual capacity and role of fungi on methane abatement is still unclear. The batch biodegradation tests here performed demonstrated the capacity of Graphium sp. to co-metabolically biodegrade methane and methanol. Moreover, the performance and microbiology of a fungal-bacterial compost biofilter treating methane at concentrations of ∼2% was evaluated at empty bed residence times of 40 and 20 min under different irrigation rates. The daily addition of 200 mL of mineral medium resulted in elimination capacities of 36.6 ± 0.7 g m(-3) h(-1) and removal efficiencies of ≈90% at the lowest residence time. The indigenous fungal community of the compost was predominant in the final microbial population and outcompeted the inoculated Graphium sp. during biofilter operation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Upward revision of global fossil fuel methane emissions based on isotope database.

    Science.gov (United States)

    Schwietzke, Stefan; Sherwood, Owen A; Bruhwiler, Lori M P; Miller, John B; Etiope, Giuseppe; Dlugokencky, Edward J; Michel, Sylvia Englund; Arling, Victoria A; Vaughn, Bruce H; White, James W C; Tans, Pieter P

    2016-10-06

    Methane has the second-largest global radiative forcing impact of anthropogenic greenhouse gases after carbon dioxide, but our understanding of the global atmospheric methane budget is incomplete. The global fossil fuel industry (production and usage of natural gas, oil and coal) is thought to contribute 15 to 22 per cent of methane emissions to the total atmospheric methane budget. However, questions remain regarding methane emission trends as a result of fossil fuel industrial activity and the contribution to total methane emissions of sources from the fossil fuel industry and from natural geological seepage, which are often co-located. Here we re-evaluate the global methane budget and the contribution of the fossil fuel industry to methane emissions based on long-term global methane and methane carbon isotope records. We compile the largest isotopic methane source signature database so far, including fossil fuel, microbial and biomass-burning methane emission sources. We find that total fossil fuel methane emissions (fossil fuel industry plus natural geological seepage) are not increasing over time, but are 60 to 110 per cent greater than current estimates owing to large revisions in isotope source signatures. We show that this is consistent with the observed global latitudinal methane gradient. After accounting for natural geological methane seepage, we find that methane emissions from natural gas, oil and coal production and their usage are 20 to 60 per cent greater than inventories. Our findings imply a greater potential for the fossil fuel industry to mitigate anthropogenic climate forcing, but we also find that methane emissions from natural gas as a fraction of production have declined from approximately 8 per cent to approximately 2 per cent over the past three decades.

  12. Upward revision of global fossil fuel methane emissions based on isotope database

    Science.gov (United States)

    Schwietzke, Stefan; Sherwood, Owen A.; Bruhwiler, Lori M. P.; Miller, John B.; Etiope, Giuseppe; Dlugokencky, Edward J.; Michel, Sylvia Englund; Arling, Victoria A.; Vaughn, Bruce H.; White, James W. C.; Tans, Pieter P.

    2016-10-01

    Methane has the second-largest global radiative forcing impact of anthropogenic greenhouse gases after carbon dioxide, but our understanding of the global atmospheric methane budget is incomplete. The global fossil fuel industry (production and usage of natural gas, oil and coal) is thought to contribute 15 to 22 per cent of methane emissions to the total atmospheric methane budget. However, questions remain regarding methane emission trends as a result of fossil fuel industrial activity and the contribution to total methane emissions of sources from the fossil fuel industry and from natural geological seepage, which are often co-located. Here we re-evaluate the global methane budget and the contribution of the fossil fuel industry to methane emissions based on long-term global methane and methane carbon isotope records. We compile the largest isotopic methane source signature database so far, including fossil fuel, microbial and biomass-burning methane emission sources. We find that total fossil fuel methane emissions (fossil fuel industry plus natural geological seepage) are not increasing over time, but are 60 to 110 per cent greater than current estimates owing to large revisions in isotope source signatures. We show that this is consistent with the observed global latitudinal methane gradient. After accounting for natural geological methane seepage, we find that methane emissions from natural gas, oil and coal production and their usage are 20 to 60 per cent greater than inventories. Our findings imply a greater potential for the fossil fuel industry to mitigate anthropogenic climate forcing, but we also find that methane emissions from natural gas as a fraction of production have declined from approximately 8 per cent to approximately 2 per cent over the past three decades.

  13. [Comparative study on biological methane potential and methanogen biodiversity in the anaerobic digestion of excess sludge].

    Science.gov (United States)

    Dong, Hui-Yu; Ji, Min

    2014-04-01

    AP and DH excess sludge, sampled from AP and DH wastewater treatment plants respectively, were inoculated with their anaerobic sludge respectively and tested with biological methane potential (BMP) method. After the regression analysis with modified Gompertz and Michaelis-Menten model, it was found that although the maximum specific CH4 production rates of AP and DH anaerobic sludge were similar [74.21 and 51.99 mL x (g x d)(-1)], the half-saturation constants K(m) differed obviously (54098 and 19005 mg x L(-)), indicating DH anaerobic sludge exhibited a higher affinity for its excess sludge. At the end of both BMP tests, the concentrations of TSS and COD(T) decreased while the concentration of NH4(+)-N increased obviously, which were more significant at higher ratios of F/M. The T-RFLP analysis results were in accordance with BMP tests. After both BMP tests, the relative amount of diverse bacteria decreased while the relative amounts of Methanosaeta spp. (280 bps), Methanomicrobiaceae (80 bps) and RC-I (389 bps) increased obviously, which were more significant in DH-BMP test compared with AP-BMP.

  14. Two-liquid phase partitioning biotrickling filters for methane abatement: exploring the potential of hydrophobic methanotrophs.

    Science.gov (United States)

    Lebrero, Raquel; Hernández, Laura; Pérez, Rebeca; Estrada, José M; Muñoz, Raúl

    2015-03-15

    The potential of two-liquid phase biotrickling filters (BTFs) to overcome mass transfer limitations derived from the poor aqueous solubility of CH4 has been scarcely investigated to date. In this context, the abatement of diluted methane emissions in two-liquid phase BTFs was evaluated using two different inocula: a type II methanotrophs culture in BTF 1 and a hydrophobic microbial consortium capable of growing inside silicone oil in BTF 2. Both BTFs supported stable elimination capacities above 45 g m(-3) h(-1) regardless of the inoculum, whereas no improvement derived from the presence of hydrophobic microorganisms compared to the type II metanotrophs culture was observed. Interestingly, the addition of silicone oil mediated a reduced metabolites concentration in the recycling aqueous phase, thus decreasing the needs for mineral medium renewal. Moreover, a 78% similarity was recorded between the microbial communities enriched in both BTFs at the end of the experimental period in spite of the differences in the initial inoculum structure. The results obtained confirmed the superior performance of two-liquid phase BTFs for CH4 abatement compared with conventional biotrickling filters.

  15. Determination of a potential set of factors which influence the situation of methane emission into roadways being driven

    Energy Technology Data Exchange (ETDEWEB)

    Marian Turek [Central Mining Institute, Katowice (Poland)

    2009-12-15

    The currently applied methodology of absolute gassiness forecasting in roadways being driven in Polish hard coal mines is based on the results of investigations over twenty years. The application of 'old' methods of forecasting of methane emission during driving of roadways often brings about great discrepancies between the results of the forecasts and actual situation. It is firstly necessary to determine a potential set of factors which exert an influence on situation regarding methane emission into roadways being driven in order to prepare a verified mathematical model of absolute gassiness forecasting. On the basis of available literature and the investigations conducted by the Central Mining Institute an initial list of factors has been prepared which can have an impact upon methane emission into roadways being driven. A prepared initial set has been scrutinized to be verified on the basis of a conducted expert survey among seventy specialists in this field. After collecting of the results of the survey their statistical elaboration was prepared. The co-efficient of agreement of multiple ordering, the so called concordance co-efficient has been taken advantage of in order to check the competency of experts. The investigations prove that the experts are in agreement in their opinions. The estimation of a collective assessment of all participants of the survey was conducted with the use of the rank sum's test by J. Gren. The results of the conducted analysis allowed determining a potential set of factors which influence the situation of methane emission into roadways being driven. This set, after conductance of further detailed investigations, can constitute a base for elaboration of a function describing methane emission into roadways being driven in hard coal mines. 11 refs., 3 tabs.

  16. Magnesium carbide synthesis from methane and magnesium oxide - a potential methodology for natural gas conversion to premium fuels and chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Diaz, A.F.; Modestino, A.J.; Howard, J.B. [Massachusetts Institute of Technology, Cambridge, MA (United States)] [and others

    1995-12-31

    Diversification of the raw materials base for manufacturing premium fuels and chemicals offers U.S. and international consumers economic and strategic benefits. Extensive reserves of natural gas in the world provide a valuable source of clean gaseous fuel and chemical feedstock. Assuming the availability of suitable conversion processes, natural gas offers the prospect of improving flexibility in liquid fuels and chemicals manufacture, and thus, the opportunity to complement, supplement, or displace petroleum-based production as economic and strategic considerations require. The composition of natural gas varies from reservoir to reservoir but the principal hydrocarbon constituent is always methane (CH{sub 4}). With its high hydrogen-to-carbon ratio, methane has the potential to produce hydrogen or hydrogen-rich products. However, methane is a very chemically stable molecule and, thus, is not readily transformed to other molecules or easily reformed to its elements (H{sub 2} and carbon). In many cases, further research is needed to augment selectivity to desired product(s), increase single-pass conversions, or improve economics (e.g. there have been estimates of $50/bbl or more for liquid products) before the full potential of these methodologies can be realized on a commercial scale. With the trade-off between gas conversion and product selectivity, a major challenge common to many of these technologies is to simultaneously achieve high methane single-pass conversions and high selectivity to desired products. Based on the results of the scoping runs, there appears to be strong indications that a breakthrough has finally been achieved in that synthesis of magnesium carbides from MgO and methane in the arc discharge reactor has been demonstrated.

  17. Review on dry reforming of methane, a potentially more environmentally-friendly approach to the increasing natural gas exploitation

    Directory of Open Access Journals (Sweden)

    Jean-Michel eLavoie

    2014-11-01

    Full Text Available With the actual growth of the natural gas industry in the US as well as the potential and availability of this non-renewable carbon source worldwide, reforming of methane gas is getting increasing attention. Methane can be used for the production of heat or electricity, as well, it can be converted to syngas, a building block that could lead to the production of liquid fuels and chemical, a very promising pathway in light of the increasing price of oil. Amongst the different reforming techniques, dry reforming could represent a very interesting approach both to valorize a cheap source or carbon (CO2 as well as to reduce the overall carbon footprint of the increasing worldwide fossil-based methane consumption. In this short review, attention will be given on the thermodynamics of dry reforming followed by an investigation on dry reforming using heterogeneous catalyst by focusing on the mots popular elements used in literature for dry reforming. Attention will as well be given to different other emerging techniques that may allow countering at one point the high thermodynamic penalties that accompanies conversion of methane using carbon dioxide.

  18. Assessment of potential greenhouse gas mitigation from changes to crop root mass and architecture

    Energy Technology Data Exchange (ETDEWEB)

    Paustian, Keith [Booz Allen Hamiltion Inc., McLean, VA (United States); Campbell, Nell [Booz Allen Hamiltion Inc., McLean, VA (United States); Dorich, Chris [Booz Allen Hamiltion Inc., McLean, VA (United States); Marx, Ernest [Booz Allen Hamiltion Inc., McLean, VA (United States); Swan, Amy [Booz Allen Hamiltion Inc., McLean, VA (United States)

    2016-01-29

    Reducing (and eventually reversing) the increase in greenhouse gases (GHGs) in the atmosphere due to human activities, and thus reducing the extent and severity of anthropogenic climate change, is one of the great challenges facing humanity. While most of the man-caused increase in GHGs has been due to fossil fuel use, land use (including agriculture) currently accounts for about 25% of total GHG emissions and thus there is a need to include emission reductions from the land use sector as part of an effective climate change mitigation strategy. In addition, analyses included in the recent IPCC 5th Climate Change Assessment report suggests that it may not be possible to achieve large enough emissions reductions in the energy, transport and industrial sectors alone to stabilize GHG concentrations at a level commensurate with a less than 2°C global average temperature increase, without the help of a substantial CO2 sink (i.e., atmospheric CO2 removal) from the land use sector. One of the potential carbon sinks that could contribute to this goal is increasing C storage in soil organic matter on managed lands. This report details a preliminary scoping analysis, to assess the potential agricultural area in the US – where appropriate soil, climate and land use conditions exist – to determine the land area on which ‘improved root phenotype’ crops could be deployed and to evaluate the potential long-term soil C storage, given a set of ‘bounding scenarios’ of increased crop root input and/or rooting depth for major crop species (e.g., row crops (corn, sorghum, soybeans), small grains (wheat, barley, oats), and hay and pasture perennial forages). The enhanced root phenotype scenarios assumed 25, 50 and 100% increase in total root C inputs, in combination with five levels of modifying crop root distributions (i.e., no change and four scenarios with increasing downward shift in root distributions). We also analyzed impacts of greater root

  19. Potential impacts from tephra fall to electric power systems: a review and mitigation strategies

    Science.gov (United States)

    Wardman, J. B.; Wilson, T. M.; Bodger, P. S.; Cole, J. W.; Stewart, C.

    2012-12-01

    Modern society is highly dependent on a reliable electricity supply. During explosive volcanic eruptions, tephra contamination of power networks (systems) can compromise the reliability of supply. Outages can have significant cascading impacts for other critical infrastructure sectors and for society as a whole. This paper summarises known impacts to power systems following tephra falls since 1980. The main impacts are (1) supply outages from insulator flashover caused by tephra contamination, (2) disruption of generation facilities, (3) controlled outages during tephra cleaning, (4) abrasion and corrosion of exposed equipment and (5) line (conductor) breakage due to tephra loading. Of these impacts, insulator flashover is the most common disruption. The review highlights multiple instances of electric power systems exhibiting tolerance to tephra falls, suggesting that failure thresholds exist and should be identified to avoid future unplanned interruptions. To address this need, we have produced a fragility function that quantifies the likelihood of insulator flashover at different thicknesses of tephra. Finally, based on our review of case studies, potential mitigation strategies are summarised. Specifically, avoiding tephra-induced insulator flashover by cleaning key facilities such as generation sites and transmission and distribution substations is of critical importance in maintaining the integrity of an electric power system.

  20. Mitigating thermal mechanical damage potential during two-photon dermal imaging.

    Science.gov (United States)

    Masters, Barry R; So, Peter T C; Buehler, Christof; Barry, Nicholas; Sutin, Jason D; Mantulin, William W; Gratton, Enrico

    2004-01-01

    Two-photon excitation fluorescence microscopy allows in vivo high-resolution imaging of human skin structure and biochemistry with a penetration depth over 100 microm. The major damage mechanism during two-photon skin imaging is associated with the formation of cavitation at the epidermal-dermal junction, which results in thermal mechanical damage of the tissue. In this report, we verify that this damage mechanism is of thermal origin and is associated with one-photon absorption of infrared excitation light by melanin granules present in the epidermal-dermal junction. The thermal mechanical damage threshold for selected Caucasian skin specimens from a skin bank as a function of laser pulse energy and repetition rate has been determined. The experimentally established thermal mechanical damage threshold is consistent with a simple heat diffusion model for skin under femtosecond pulse laser illumination. Minimizing thermal mechanical damage is vital for the potential use of two-photon imaging in noninvasive optical biopsy of human skin in vivo. We describe a technique to mitigate specimen thermal mechanical damage based on the use of a laser pulse picker that reduces the laser repetition rate by selecting a fraction of pulses from a laser pulse train. Since the laser pulse picker decreases laser average power while maintaining laser pulse peak power, thermal mechanical damage can be minimized while two-photon fluorescence excitation efficiency is maximized.

  1. GHG Mitigation Potential, Costs and Benefits in Global Forests: ADynamic Partial Equilibrium Approach

    Energy Technology Data Exchange (ETDEWEB)

    Sathaye, Jayant; Makundi, Willy; Dale, Larry; Chan, Peter; Andrasko, Kenneth

    2005-03-22

    This paper reports on the global potential for carbonsequestration in forest plantations, and the reduction of carbonemissions from deforestation, in response to six carbon price scenariosfrom 2000 to 2100. These carbon price scenarios cover a range typicallyseen in global integrated assessment models. The world forest sector wasdisaggregated into tenregions, four largely temperate, developedregions: the European Union, Oceania, Russia, and the United States; andsix developing, mostly tropical, regions: Africa, Central America, China,India, Rest of Asia, and South America. Three mitigation options -- long-and short-rotation forestry, and the reduction of deforestation -- wereanalyzed using a global dynamic partial equilibrium model (GCOMAP). Keyfindings of this work are that cumulative carbon gain ranges from 50.9 to113.2 Gt C by 2100, higher carbon prices early lead to earlier carbongain and vice versa, and avoided deforestation accounts for 51 to 78percent of modeled carbon gains by 2100. The estimated present value ofcumulative welfare change in the sector ranges from a decline of $158billion to a gain of $81 billion by 2100. The decline is associated witha decrease in deforestation.

  2. Beyond Failure: Potentially Mitigating Failed Author Searches in the Online Library Catalog through the Use of Linked Data

    Science.gov (United States)

    Moulaison, Heather Lea; Stanley, Susan Nicole

    2013-01-01

    Linked data stores house vetted content that can supplement the information available through online library catalogs, potentially mitigating failed author searches if information about the author exists in linked data formats. In this case study, a total of 689 failed author index queries from a large Midwestern academic library's online library…

  3. Importance of biophysical effects on climate warming mitigation potential of biofuel crops over the conterminous United Sta

    Science.gov (United States)

    Current quantification of Climate Warming Mitigation Potential (CWMP) of biomass-derived energy has focused primarily on its biogeochemical effects. This study used site-level observations of carbon, water, and energy fluxes of biofuel crops to parameterize and evaluate the Community Land Model (CLM...

  4. Relation between methanogenic archaea and methane production potential in selected natural wetland ecosystems across China

    Science.gov (United States)

    Liu, D. Y.; Ding, W. X.; Jia, Z. J.; Cai, Z. C.

    2011-02-01

    Methane (CH4) emissions from natural wetland ecosystems exhibit large spatial variability at regional, national, and global levels related to temperature, water table, plant type and methanogenic archaea etc. To understand the underlying factors that induce spatial differences in CH4 emissions, and the relationship between the population of methanogenic archaea and CH4 production potential in natural wetlands around China, we measured the CH4 production potential and the abundance of methanogenic archaea in vertical soil profiles sampled from the Poyang wetland in the subtropical zone, the Hongze wetland in the warm temperate zone, the Sanjiang marsh in the cold temperate zone, and the Ruoergai peatland in the Qinghai-Tibetan Plateau in the alpine climate zone. The top soil layer had the highest population of methanogens (1.07-8.29 × 109 cells g-1 soil) in all wetlands except the Ruoergai peatland and exhibited the maximum CH4 production potential measured at the mean in situ summer temperature. There is a significant logarithmic correlation between the abundance of methanogenic archaea and the soil organic carbon (R2 = 0.72, P nitrogen concentrations (R2 = 0.76, P affect the population of methanogens in wetland ecosystems. While the CH4 production potential is not significantly related to methanogen population (R2 = 0.01, P > 0.05, n = 13), it is related to the dissolved organic carbon concentration (R2 = 0.31, P = 0.05, n = 13). This suggests that the methanogen population might be not an effective index for predicting the CH4 production in wetland ecosystems. The CH4 production rate of the top soil layer increases with increasing latitude, from 273.64 μg CH4 kg-1 soil d-1 in the Poyang wetland to 664.59 μg CH4 kg-1 soil d-1 in the Carex lasiocarpa marsh of the Sanjiang Plain. We conclude that CH4 production potential in the freshwater wetlands of Eastern China is mainly affected by the supply of methanogenic substrates rather than temperature; in contrast

  5. Mitigation of methane and nitrous oxide emissions from flood-irrigated rice by no incorporation of winter crop residues into the soil

    Directory of Open Access Journals (Sweden)

    Tiago Zschornack

    2011-04-01

    Full Text Available Winter cover crops are sources of C and N in flooded rice production systems, but very little is known about the effect of crop residue management and quality on soil methane (CH4 and nitrous oxide (N2O emissions. This study was conducted in pots in a greenhouse to evaluate the influence of crop residue management (incorporated into the soil or left on the soil surface and the type of cover-crop residues (ryegrass and serradella on CH4 and N2O emissions from a flooded Albaqualf soil cultivated with rice (Oryza sativa L.. The closed chamber technique was used for air sampling and the CH4 and N2O concentrations were analyzed by gas chromatography. Soil solution was sampled at two soil depths (2 and 20 cm, simultaneously to air sampling, and the contents of dissolved organic C (DOC, NO3-, NH4+, Mn2+, and Fe2+ were analyzed. Methane and N2O emissions from the soil where crop residues had been left on the surface were lower than from soil with incorporated residues. The type of crop residue had no effect on the CH4 emissions, while higher N2O emissions were observed from serradella (leguminous than from ryegrass, but only when the residues were left on the soil surface. The more intense soil reduction verified in the deeper soil layer (20 cm, as evidenced by higher contents of reduced metal species (Mn2+ and Fe2+, and the close relationship between CH4 emission and the DOC contents in the deeper layer indicated that the sub-surface layer was the main CH4 source of the flooded soil with incorporated crop residues. The adoption of management strategies in which crop residues are left on the soil surface is crucial to minimize soil CH4 and N2O emissions from irrigated rice fields. In these production systems, CH4 accounts for more than 90 % of the partial global warming potential (CH4+N2O and, thus, should be the main focus of research.

  6. Ozonation and thermal pre-treatment of municipal sewage sludge – Implications for toxicity and methane potential

    DEFF Research Database (Denmark)

    Davidsson, A.; Eriksson, Eva; Fick, J.

    The aim of this study was to determine the effects on the methane potential and the overall sludge quality from two different sludge pre-treatment technologies (ozonation high/low dosage and thermal treatment 55/70 °C). In general both treatments gave an increased methane potential. The thermal...... treatment resulted in higher chemical oxygen demand (COD)-solubilisation, while the highest volatile fatty acids (VFA) increase was obtained with ozonation. The sludges had inhibiting effects in a barley seed germination assay and a yeast oestrogen screen both before and after pre-treatment......, but the inhibition was reduced by ozone treatment and digestion. No statistical significant reduction in concentrations of the included pharmaceuticals could be seen....

  7. Potential methane production rates and its carbon isotopic composition from ornithogenic tundra soils in coastal Antarctic

    Institute of Scientific and Technical Information of China (English)

    BAO Tao; ZHU Renbin; BAI Bo; XU Hua

    2016-01-01

    Methane (CH4) is one of important greenhouse gases with chemical activity. The determination of isotopic compositions for CH4 emitted from the soils helps us to understand its production mechanisms. CH4 isotope measurements have been conducted for different types of global terrestrial ecosystems. However, no isotopic data of CH4 have been reported from Antarctic tundra soils. In this paper, ornithogenic soil profiles were collected from four penguin colonies, and potential CH4 production rates and its13C ratio (δ13C) were investigated based upon laboratory incubation experiments. The mean CH4 production rates are highly variable in these soil proifles, ranging from 0.7 to 20.3 μg CH4−C kg−1∙h−1. These ornithogenic soils had high potential production rates of CH4 under ambient air incubation or under N2 incubation, indicating the importance of potential CH4 emissions from penguin colonies. Most of the soil samples had higher δ13C-CH4 under N2 incubation (−39.28%~−43.53%) than under the ambient air incubation (−42.81%~−57.19%). Highly anaerobic conditions were conducive to the production of CH4 enriched in13C, and acetic acid reduction under N2 incubation might be a predominant source for soil CH4production. Overall theδ13C-CH4 showed a signiifcant negative correlation with CH4 production rates in ornithogenic tundra soils under N2 incubation (R2=0.41,p<0.01) or under the ambient air incubation (R2=0.50,p<0.01). Potential CH4 production from ornithogenic soils showed a signiifcant positive correlation with total phosphorus (TP) and NH4+−N contents, pH and soil moisture (Mc), but the δ13C-CH4 showed a signiifcant negative correlation with TP and NH4+−N contents, pH and Mc, indicating that the deposition amount of penguin guano increased potential CH4 production rates from tundra soils, but decreased the δ13C-CH4. The CH4 emissions from the ornithogenic soils affect carbon isotopic compositions of atmospheric CH4in coastal Antarctica.

  8. In-vitro fermentation characteristics and methane reduction potential of mustard cake (Brassica juncea L.

    Directory of Open Access Journals (Sweden)

    S. M. Durge

    2016-10-01

    Full Text Available Aim: To assess the effect of mustard cake (Brassica juncea L. levels in concentrate mixtures and in composite feed mixtures (CFMs on in-vitro fermentation characteristics and methane production. Materials and Methods: Five concentrate mixtures were prepared with containing 30% oil cake, where linseed cake was replaced by mustard cake at the rate of 0%, 7.5%, 15.0%, 22.5%, and 30% in concentrate mixture. Mustard cake contained glucosinolate 72.58 μmol/g oil free dry matter (DM and contents in diet were 0, 5.4, 10.9, 16.3, and 21.8 μmol/g of concentrate mixture, respectively. Concentrate mixture containing 15.0% mustard cake was found to produced minimum methane which was then used for the preparation of CFM containing 0%, 25%, 50%, and 75% levels with gram straw. Result: Increased levels of mustard cake in concentrate mixtures had a linear decrease (p<0.05 in the total gas production, and the 15% inclusion showed lowest methane concentration (quadratic, p<0.01. The degradability of DM and organic matter (OM of concentrate mixtures did not change, however, pH and NH3-N concentrations of the fermentation medium showed linear (p<0.05 reductions with increased mustard cake levels. Increased levels of 15% mustard cake containing concentrate mixture in CFMs exhibited a trend (p=0.052 of increased gas production, whereas methane concentration in total gas, methane produced and degradability of DM and OM were also displayed a linear increase (p<0.05. However, the pH, NH3-N, and total volatile fatty acid levels decreased linearly (p<0.05 with increased levels of concentrate in CFMs. Conclusion: Reduction in methane production was evidenced with the inclusion of mustard cake in concentrate mixture at 15% level, and the CFMs with 25% concentrate, which contained 15% mustard cake, exhibited an improved fermentation and reduced methane production.

  9. Pig feeding strategy coupled with effluent management - fresh or stored slurry, solid phase separation - on methane potential and methane conversion factors during storage

    Science.gov (United States)

    Jarret, Guillaume; Martinez, José; Dourmad, Jean-Yves

    2011-11-01

    In the guideline for the determination of methane (CH 4) emission from animal manure (IPCC) the amount of CH 4 emitted is generally calculated according to an equation combining the amount of organic matter (OM) or volatile solids excreted, the ultimate CH 4 potential ( B0) of excreta and a system-specific methane conversion factor (MCF, %) that reflects the portion of B0 that is really converted into CH 4. The objective of the present study was to investigate the effect of the modification of dietary crude protein and fibre levels on B0 of pig slurry and on subsequent MCF according to different strategies of slurry management. Five experimental diets differing mainly in their crude protein and fibre content were compared. Two types of measurement of CH 4 emission were performed. The first was the measurement of B0 of slurry using biomethanogene potential (BMP) test. The second consisted in a storage simulation, which was performed on different kinds of effluents: fresh slurry (FSl), stored slurry (SSl), and faeces mixed with water (FaW). The type of diet and the type of effluent affected ( P dietary treatments whereas it differed for storage simulation studies with significant effects of dietary CP and fibre contents. The results from this study indicate that the type of diet has a significant but rather limited effect on B0 value of effluent. The effect of diet is much more marked on MCF, with lower values for high protein diets, and higher values for high fibre diets. MCF is also affected by manure management, the values measured on separated faeces from urine being much higher than for slurry.

  10. Biomass production and biochemical methane potential of seasonally flooded inter-generic and inter-specific Saccharum hybrids

    Energy Technology Data Exchange (ETDEWEB)

    Deren, C.W.; Snyder, G.H. (Florida Univ., Belle Glade, FL (United States). Agricultural Research and Education Center); Tai, P.Y.P. (Department of Agriculture, Canal Point, FL (US). Sugarcane Field Station); Turick, C.E.; Chynoweth, D.P. (Florida Univ., Gainesville, FL (United States). Dept. of Agricultural Engineering)

    1991-01-01

    Production of biomass crops for energy can compete with food crop production for quality, arable land. Certain biomass crops may be well suited to marginal sites which do not favor food crop production. This study was conducted to evaluate biomass production on a wetland site which, without extensive and costly conversion, would be unsuitable for conventional agricultural production. Nine clones of the Saccharum taxonomic complex were evaluated for biomass production and methane conversion after being flooded for six months in each of two crop years. Erianthus arundinaceus clones were intolerant of flood and subsequently were low in biomass production. Inter-specific and inter-generic hybrids of commercial sugarcane with E. arundinaceus and S. spontaneum produced well under flood. All clones were more productive in ratoon (regrowth crop). Rates of methane conversion under mesophilic conditions (35{sup o}C) ranged from 0.060 to 0.095 day{sup -1} and methane yield was from 0.266 to 0.314 liter g{sup -1} volatile solids (VS). Biomass dry matter yield varied widely from 0.47 to 20.28 Mg ha{sup -1} in the plant-crop and 4.57 to 60.1 Mg ha{sup -1} in ratoon. Using the mean sample value observed for methane yield, this corresponds to upper methane yields of 5.89 and 17.4 x 10{sup 6} liter ha{sup -1} for the plant and ratoon crops, respectively. The wide crosses appear to have good potential for biomass production in areas prone to periodic flooding. (author).

  11. C-H bond activation of methane in aqueous solution: a hybrid quantum mechanical/effective fragment potential study.

    Science.gov (United States)

    Da Silva, Júlio C S; Rocha, Willian R

    2011-12-01

    In this study, we investigated the C-H bond activation of methane catalyzed by the complex [PtCl(4)](2-), using the hybrid quantum mechanical/effective fragment potential (EFP) approach. We analyzed the structures, energetic properties, and reaction mechanism involved in the elementary steps that compose the catalytic cycle of the Shilov reaction. Our B3LYP/SBKJC/cc-pVDZ/EFP results show that the methane activation may proceed through two pathways: (i) electrophilic addition or (ii) direct oxidative addition of the C-H bond of the alkane. The electrophilic addition pathway proceeds in two steps with formation of a σ-methane complex, with a Gibbs free energy barrier of 24.6 kcal mol(-1), followed by the cleavage of the C-H bond, with an energy barrier of 4.3 kcal mol(-1) . The activation Gibbs free energy, calculated for the methane uptake step was 24.6 kcal mol(-1), which is in good agreement with experimental value of 23.1 kcal mol(-1) obtained for a related system. The results shows that the activation of the C-H bond promoted by the [PtCl(4)](2-) catalyst in aqueous solution occurs through a direct oxidative addition of the C-H bond, in a single step, with an activation free energy of 25.2 kcal mol(-1), as the electrophilic addition pathway leads to the formation of a σ-methane intermediate that rapidly undergoes decomposition. The inclusion of long-range solvent effects with polarizable continuum model does not change the activation energies computed at the B3LYP/SBKJC/cc-pVDZ/EFP level of theory significantly, indicating that the large EFP water cluster used, obtained from Monte Carlo simulations and analysis of the center-of-mass radial pair distribution function, captures the most important solvent effects.

  12. Biochemical methane potential, biodegradability, alkali treatment and influence of chemical composition on methane yield of yard wastes.

    Science.gov (United States)

    Gunaseelan, Victor Nallathambi

    2016-03-01

    In this study, the biochemical CH4 potential, rate, biodegradability, NaOH treatment and the influence of chemical composition on CH4 yield of yard wastes generated from seven trees were examined. All the plant parts were sampled for their chemical composition and subjected to the biochemical CH4 potential assay. The component parts exhibited significant variation in biochemical CH4 potential, which was reflected in their ultimate CH4 yields that ranged from 109 to 382 ml g(-1) volatile solids added and their rate constants that ranged from 0.042 to 0.173 d(-1). The biodegradability of the yard wastes ranged from 0.26 to 0.86. Variation in the biochemical CH4 potential of the yard wastes could be attributed to variation in the chemical composition of the different fractions. In the Thespesia yellow withered leaf, Tamarindus fruit pericarp and Albizia pod husk, NaOH treatment enhanced the ultimate CH4 yields by 17%, 77% and 63%, respectively, and biodegradability by 15%, 77% and 61%, respectively, compared with the untreated samples. The effectiveness of NaOH treatment varied for different yard wastes, depending on the amounts of acid detergent fibre content. Gliricidia petals, Prosopis leaf, inflorescence and immature pod, Tamarindus seeds, Albizia seeds, Cassia seeds and Delonix seeds exhibited CH4 yields higher than 300 ml g(-1) volatile solids added. Multiple linear regression models for predicting the ultimate CH4 yield and biodegradability of yard wastes were designed from the results of this work.

  13. Geology, reservoir engineering and methane hydrate potential of the Walakpa Gas Field, North Slope, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Glenn, R.K.; Allen, W.W.

    1992-12-01

    The Walakpa Gas Field, located near the city of Barrow on Alaska's North Slope, has been proven to be methane-bearing at depths of 2000--2550 feet below sea level. The producing formation is a laterally continuous, south-dipping, Lower Cretaceous shelf sandstone. The updip extent of the reservoir has not been determined by drilling, but probably extends to at least 1900 feet below sea level. Reservoir temperatures in the updip portion of the reservoir may be low enough to allow the presence of in situ methane hydrates. Reservoir net pay however, decreases to the north. Depths to the base of permafrost in the area average 940 feet. Drilling techniques and production configuration in the Walakpa field were designed to minimize formation damage to the reservoir sandstone and to eliminate methane hydrates formed during production. Drilling development of the Walakpa field was a sequential updip and lateral stepout from a previously drilled, structurally lower confirmation well. Reservoir temperature, pressure, and gas chemistry data from the development wells confirm that they have been drilled in the free-methane portion of the reservoir. Future studies in the Walakpa field are planned to determine whether or not a component of the methane production is due to the dissociation of updip in situ hydrates.

  14. Full Dimensional Vibrational Calculations for Methane Using AN Accurate New AB Initio Based Potential Energy Surface

    Science.gov (United States)

    Majumder, Moumita; Dawes, Richard; Wang, Xiao-Gang; Carrington, Tucker; Li, Jun; Guo, Hua; Manzhos, Sergei

    2014-06-01

    New potential energy surfaces for methane were constructed, represented as analytic fits to about 100,000 individual high-level ab initio data. Explicitly-correlated multireference data (MRCI-F12(AE)/CVQZ-F12) were computed using Molpro [1] and fit using multiple strategies. Fits with small to negligible errors were obtained using adaptations of the permutation-invariant-polynomials (PIP) approach [2,3] based on neural-networks (PIP-NN) [4,5] and the interpolative moving least squares (IMLS) fitting method [6] (PIP-IMLS). The PESs were used in full-dimensional vibrational calculations with an exact kinetic energy operator by representing the Hamiltonian in a basis of products of contracted bend and stretch functions and using a symmetry adapted Lanczos method to obtain eigenvalues and eigenvectors. Very close agreement with experiment was produced from the purely ab initio PESs. References 1- H.-J. Werner, P. J. Knowles, G. Knizia, 2012.1 ed. 2012, MOLPRO, a package of ab initio programs. see http://www.molpro.net. 2- Z. Xie and J. M. Bowman, J. Chem. Theory Comput 6, 26, 2010. 3- B. J. Braams and J. M. Bowman, Int. Rev. Phys. Chem. 28, 577, 2009. 4- J. Li, B. Jiang and Hua Guo, J. Chem. Phys. 139, 204103 (2013). 5- S Manzhos, X Wang, R Dawes and T Carrington, JPC A 110, 5295 (2006). 6- R. Dawes, X-G Wang, A.W. Jasper and T. Carrington Jr., J. Chem. Phys. 133, 134304 (2010).

  15. Oregon Trust Agreement Planning Project : Potential Mitigations to the Impacts on Oregon Wildlife Resources Associated with Relevant Mainstem Columbia River and Willamette River Hydroelectric Projects.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1993-10-01

    A coalition of the Oregon wildlife agencies and tribes (the Oregon Wildlife Mitigation Coalition) have forged a cooperative effort to promote wildlife mitigation from losses to Oregon wildlife resources associated with the four mainstream Columbia River and the eight Willamette River Basin hydroelectric projects. This coalition formed a Joint Advisory Committee, made up of technical representatives from all of the tribes and agencies, to develop this report. The goal was to create a list of potential mitigation opportunities by priority, and to attempt to determine the costs of mitigating the wildlife losses. The information and analysis was completed for all projects in Oregon, but was gathered separately for the Lower Columbia and Willamette Basin projects. The coalition developed a procedure to gather information on potential mitigation projects and opportunities. All tribes, agencies and interested parties were contacted in an attempt to evaluate all proposed or potential mitigation. A database was developed and minimum criteria were established for opportunities to be considered. These criteria included the location of the mitigation site within a defined area, as well as other criteria established by the Northwest Power Planning Council. Costs were established for general habitats within the mitigation area, based on estimates from certified appraisers. An analysis of the cost effectiveness of various types of mitigation projects was completed. Estimates of operation and maintenance costs were also developed. The report outlines strategies for gathering mitigation potentials, evaluating them, determining their costs, and attempting to move towards their implementation.

  16. Determination of a potential set of factors which influence the situation of methane emission into roadways being driven

    Institute of Scientific and Technical Information of China (English)

    Marian Turek

    2009-01-01

    The currently applied methodology of absolute gassiness forecasting in roadways being driven in Polish hard coal mines is based on the results of investigations from before more than twenty years. At present the roadways are being driven in majority of cases in quite different conditions than those which had been the subject of the said investigations. The application of "old" methods of forecasting of methane emission during driving of roadways often brings about great discrepancies between the results of the forecasts and actual situation. It is firstly necessary to determine a potential set of factors which exert an influence on situation regarding methane emission into roadways being driven in order to prepare a verified mathematical model of absolute gassiness forecasting. On the basis of available literature and the investigations conducted by the Central Mining Institute an initial list of factors has been prepared which can have an impact upon methane emission into roadways being driven. The assumptions of heuristic method have been taken advantage of for selection of parameters and indices describing the phenomenon of methane emission. It has been dictated by the fact that the available literature is lacking a pretty unambiguous viewpoint on the subject under consideration and at the same time it is necessary to perform an a priori assessment of the information contained in a given feature (factor). A prepared initial set has been scrutinized to be verified on the basis of a conducted expert survey among seventy specialists in this field. After collecting of the results of the survey their statistical elaboration was prepared. The co-efficient of agreement of multiple ordering, the so called concordance co-efficient has been taken advantage of in order to check the competency of experts. The investigations prove that the experts are in agreement in their opinions. The estimation of a collective assessment of all participants of the survey was conducted

  17. Geochemical investigation of the potential for mobilizing non-methane hydrocarbons during carbon dioxide storage in deep coal beds

    Science.gov (United States)

    Kolak, J.J.; Burruss, R.C.

    2006-01-01

    Coal samples of different rank (lignite to anthracite) were extracted in the laboratory with supercritical CO2 (40 ??C; 10 MPa) to evaluate the potential for mobilizing non-methane hydrocarbons during CO2 storage (sequestration) or enhanced coal bed methane recovery from deep (???1-km depth) coal beds. The total measured alkane concentrations mobilized from the coal samples ranged from 3.0 to 64 g tonne-1 of dry coal. The highest alkane concentration was measured in the lignite sample extract; the lowest was measured in the anthracite sample extract. Substantial concentrations of polycyclic aromatic hydrocarbons (PAHs) were also mobilized from these samples: 3.1 - 91 g tonne-1 of dry coal. The greatest amounts of PAHs were mobilized from the high-volatile bituminous coal samples. The distributions of aliphatic and aromatic hydrocarbons mobilized from the coal samples also varied with rank. In general, these variations mimicked the chemical changes that occur with increasing degrees of coalification and thermal maturation. For example, the amount of PAHs mobilized from coal samples paralleled the general trend of bitumen formation with increasing coal rank. The coal samples yielded hydrocarbons during consecutive extractions with supercritical CO2, although the amount of hydrocarbons mobilized declined with each successive extraction. These results demonstrate that the potential for supercritical CO2 to mobilize non-methane hydrocarbons from coal beds, and the effect of coal rank on this process, are important to consider when evaluating deep coal beds for CO2 storage.

  18. Relation between methanogenic archaea and methane production potential in selected natural wetland ecosystems across China

    Directory of Open Access Journals (Sweden)

    D. Y. Liu

    2011-02-01

    Full Text Available Methane (CH4 emissions from natural wetland ecosystems exhibit large spatial variability at regional, national, and global levels related to temperature, water table, plant type and methanogenic archaea etc. To understand the underlying factors that induce spatial differences in CH4 emissions, and the relationship between the population of methanogenic archaea and CH4 production potential in natural wetlands around China, we measured the CH4 production potential and the abundance of methanogenic archaea in vertical soil profiles sampled from the Poyang wetland in the subtropical zone, the Hongze wetland in the warm temperate zone, the Sanjiang marsh in the cold temperate zone, and the Ruoergai peatland in the Qinghai-Tibetan Plateau in the alpine climate zone. The top soil layer had the highest population of methanogens (1.07–8.29 × 109 cells g−1 soil in all wetlands except the Ruoergai peatland and exhibited the maximum CH4 production potential measured at the mean in situ summer temperature. There is a significant logarithmic correlation between the abundance of methanogenic archaea and the soil organic carbon (R2 = 0.72, P < 0.001, n = 13 and between the abundance of methanogenic archaea and the total nitrogen concentrations (R2 = 0.76, P < 0.001, n = 13 in wetland soils. This indicates that the amount of soil organic carbon may affect the population of methanogens in wetland ecosystems. While the CH4 production potential is not significantly related to methanogen population (R2 = 0.01, P > 0.05, n = 13, it is related to the dissolved organic carbon concentration (R2 = 0.31, P = 0.05, n = 13. This suggests that the methanogen population might be not an effective index for predicting the CH4 production in wetland

  19. Relation between soil matrix potential changes and water conversion ratios during methane hydrate formation processes in loess

    Institute of Scientific and Technical Information of China (English)

    Peng Zhang; Qingbai Wu; Guanli Jiang; Yibin Pu

    2011-01-01

    With a new apparatus designed and assembled by ourselves,the matrix potential of non-saturated loess was firstly measured and studied during methane hydrate formation processes.The experimental results showed that during two formation processes,the matrix potential changes of the loess all presented a good linear relationship with water conversion ratios.In addition,although it was well known that the secondary gas hydrate formation was easier than the initial,our experimental results showed that the initial hydrate formation efficiency in non-saturated loess was higher than that of the secondary.

  20. Simple Fabrication Process for 2D ZnO Nanowalls and Their Potential Application as a Methane Sensor

    Directory of Open Access Journals (Sweden)

    Zhan-Shuo Hu

    2013-03-01

    Full Text Available Two-dimensional (2D ZnO nanowalls were prepared on a glass substrate by a low-temperature thermal evaporation method, in which the fabrication process did not use a metal catalyst or the pre-deposition of a ZnO seed layer on the substrate. The nanowalls were characterized for their surface morphology, and the structural and optical properties were investigated using scanning electron microscopy (SEM, X-ray diffraction (XRD, transmission electron microscopy (TEM, and photoluminescence (PL. The fabricated ZnO nanowalls have many advantages, such as low growth temperature and good crystal quality, while being fast, low cost, and easy to fabricate. Methane sensor measurements of the ZnO nanowalls show a high sensitivity to methane gas, and rapid response and recovery times. These unique characteristics are attributed to the high surface-to-volume ratio of the ZnO nanowalls. Thus, the ZnO nanowall methane sensor is a potential gas sensor candidate owing to its good performance.

  1. Simple fabrication process for 2D ZnO nanowalls and their potential application as a methane sensor.

    Science.gov (United States)

    Chen, Tse-Pu; Chang, Sheng-Po; Hung, Fei-Yi; Chang, Shoou-Jinn; Hu, Zhan-Shuo; Chen, Kuan-Jen

    2013-03-20

    Two-dimensional (2D) ZnO nanowalls were prepared on a glass substrate by a low-temperature thermal evaporation method, in which the fabrication process did not use a metal catalyst or the pre-deposition of a ZnO seed layer on the substrate. The nanowalls were characterized for their surface morphology, and the structural and optical properties were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), and photoluminescence (PL). The fabricated ZnO nanowalls have many advantages, such as low growth temperature and good crystal quality, while being fast, low cost, and easy to fabricate. Methane sensor measurements of the ZnO nanowalls show a high sensitivity to methane gas, and rapid response and recovery times. These unique characteristics are attributed to the high surface-to-volume ratio of the ZnO nanowalls. Thus, the ZnO nanowall methane sensor is a potential gas sensor candidate owing to its good performance.

  2. Methane Potential and Microbial Community Dynamics in Anaerobic Digestion of Silage and Dry Cornstalks: a Substrate Exchange Study.

    Science.gov (United States)

    Zhao, Ye; Yuan, Xufeng; Wen, Boting; Wang, Xiaofen; Zhu, Wanbin; Cui, Zongjun

    2017-01-01

    Silage and dry are the two typical cornstalk forms. Either form could be used as substrate in biogas plants and might be replaced by another when shortage occurred. This study focused on the feeding sequence of these two kinds of feedstocks, aiming to discuss their specific methane potential (SMP). A 15-day hydraulic retention time was chosen for semi-continuous experiments based on the batch test results. In semi-continuous experiments, before and after feedstocks were exchanged, the significantly decreased and comparable SMPs of silage and dry cornstalks indicated that a basis of unstable digestion would result in incomplete methane release from the subsequent digestion. A higher similarity of bacterial community structure and greater quantity of bacteria were shown in acidified silage cornstalk digestion through band similarity analysis. Methanosaetaceae and methanomicrobiales were the predominant methanogens, and aceticlastic methanogenesis was the main route for methane production. The different feeding sequences affected the hydrolysis course and further influenced the methanogenic proliferation. Our work suggests that silage cornstalk digestion should be conducted before dry cornstalk digestion.

  3. Do Agricultural Soils of California have the Potential to Sequester Carbon and Mitigate Greenhouse Gases?

    Science.gov (United States)

    Suddick, E. C.; Scow, K. M.; Six, J. W.

    2008-12-01

    Agricultural ecosystems play a major role in the global carbon cycle and can be both sources of carbon emissions to the atmosphere and also carbon sinks which may be used to offset any future greenhouse gas (GHG) emissions. In California, climate change predictions indicate major impacts and substantial alterations of agricultural systems over the next decades. In 2006, California passed the California Global Warming Solutions Act of 2006 (AB 32) that requires reduction of the three major GHG's (CO2, N2O and CH4) to 1990 levels by 2020. We surveyed and synthesized available data from recent studies describing the potential to sequester carbon and reduce other GHG emissions in California agricultural soils. The studies evaluated various management practices in both annual row and perennial cropping systems, with other studies focusing upon biogeochemical model predictions for carbon sequestration and GHG mitigation calibrated towards California agriculture. Management practices considered included minimum or no tillage, cover cropping, organic residue (low and high inputs) and nitrogen fertilizer management. Though practices involving inputs of carbon, such as cover cropping and organic amendments, were often associated with increases in soil organic carbon (SOC) in the top soil layer (0-20 cm), results were not consistent across farming systems. Several studies indicated that conservation tillage, alone, increased above-ground biomass, especially when used with a cover crop. However, the reduced soil disturbance from conservation tillage merely resulted in a redistribution of the soil carbon rather than an overall accumulation, when compared with standard tillage and cover cropping practices together. Predictions from biogeochemical models indicated that increased inputs of manure and increased organic residues led to substantial carbon sequestration but did not consistently reduce non-CO2 related GHG emissions. The most effective way to reduce non-CO2 GHG

  4. Efficient production of ethanol from waste paper and the biochemical methane potential of stillage eluted from ethanol fermentation.

    Science.gov (United States)

    Nishimura, Hiroto; Tan, Li; Sun, Zhao-Yong; Tang, Yue-Qin; Kida, Kenji; Morimura, Shigeru

    2016-02-01

    Waste paper can serve as a feedstock for ethanol production due to being rich in cellulose and not requiring energy-intensive thermophysical pretreatment. In this study, an efficient process was developed to convert waste paper to ethanol. To accelerate enzymatic saccharification, pH of waste paper slurry was adjusted to 4.5-5.0 with H2SO4. Presaccharification and simultaneous saccharification and fermentation (PSSF) with enzyme loading of 40 FPU/g waste paper achieved an ethanol yield of 91.8% and productivity of 0.53g/(Lh) with an ethanol concentration of 32g/L. Fed-batch PSSF was used to decrease enzyme loading to 13 FPU/g waste paper by feeding two separate batches of waste paper slurry. Feeding with 20% w/w waste paper slurry increased ethanol concentration to 41.8g/L while ethanol yield decreased to 83.8%. To improve the ethanol yield, presaccharification was done prior to feeding and resulted in a higher ethanol concentration of 45.3g/L, a yield of 90.8%, and productivity of 0.54g/(Lh). Ethanol fermentation recovered 33.2% of the energy in waste paper as ethanol. The biochemical methane potential of the stillage eluted from ethanol fermentation was 270.5mL/g VTS and 73.0% of the energy in the stillage was recovered as methane. Integrating ethanol fermentation with methane fermentation, recovered a total of 80.4% of the energy in waste paper as ethanol and methane.

  5. Biochemical methane potential of fractions of organic matter extracted from a municipal solid waste leachate: Impact of their hydrophobic character.

    Science.gov (United States)

    Baccot, Camille; Pallier, Virginie; Feuillade-Cathalifaud, Geneviève

    2016-12-05

    Many data on anaerobic digestion (AD) and co-digestion of municipal solid waste leachate (MSWL) are already available in literature. They mainly deal with its performances to decrease the chemical oxygen demand (COD) of MSWL and no information is given on the impact of the specific characteristics of the dissolved organic matter (DOM) in leachate on these performances. DOM in leachate evolves towards more aromatic and hydrophobic compounds during landfilling with increasing specific ultra-violet absorbance index (SUVA) and hydrophobic character. However, according to the humification stages, this DOM would not present the same aptitude for AD. This research thus focused on (i) optimizing a biochemical methane potential (BMP) test applied to MSWL by using the Taguchi method and (ii) evaluating the impact of the hydrophobic character of the DOM in leachate on the BMP of MSWL to finally define the humification degree more suitable for AD. Hydrophobic-like (HPO(∗)) and transphilic-like (TPH(∗)) compounds extracted from leachate by a fractionation protocol were tested because of their high content in MSWL during acetogenesis and methanogenesis steps. After 275days of AD, the content in hydrophobic compounds and the SUVA indexes increased in the digestates. Moreover, even if the biogas and methane productions were not significantly different during the whole tests (4072±350mLgDOC(-1) and 2370±95mLgDOC(-1) respectively), the volume of biogas produced directly correlated with the TPH(∗) fraction content in the initial digestates. On the contrary, the methane percentage in biogas was anti-correlated with the hydrophilic-like compounds content. The hydrophobic-like molecules seem thus not to be directly involved in the methanogenic step, however they promote the increase of the methane percent in the biogas.

  6. Methane oxidation potential of boreal landfill cover materials: The governing factors and enhancement by nutrient manipulation.

    Science.gov (United States)

    Maanoja, Susanna T; Rintala, Jukka A

    2015-12-01

    Methanotrophs inhabiting landfill covers are in a crucial role in mitigating CH4 emissions, but the characteristics of the cover material or ambient temperature do not always enable the maximal CH4 oxidation potential (MOP). This study aimed at identifying the factors governing MOPs of different materials used for constructing biocovers and other cover structures. We also tested whether the activity of methanotrophs could be enhanced at cold temperature (4 and 12°C) by improving the nutrient content (NO3(-), PO4(3-), trace elements) of the cover material. Compost samples from biocovers designed to support CH4 oxidation were exhibiting the highest MOPs (4.16 μmol CH4 g dw(-1) h(-1)), but also the soil samples collected from other cover structures were oxidising CH4 (0.41 μmol CH4 g dw(-1) h(-1)). The best predictors for the MOPs were the NO3(-) content and activity of heterotrophic bacteria at 72.8%, which were higher in the compost samples than in the soil samples. The depletion of NO3(-) from the landfill cover material limiting the activity of methanotrophs could not be confirmed by the nutrient manipulation assay at 4°C as the addition of nitrogen decreased the MOPs from 0.090 μmol CH4 g dw(-1) h(-1) to 0.096 μmol CH4 g dw(-1)h(-1)) suggesting that this was attributable to stimulation of the enzymatic activity of the psychrotolerant methanotrophs.

  7. Climate Change and Air Pollution: Exploring the Synergies and Potential for Mitigation in Industrializing Countries

    Directory of Open Access Journals (Sweden)

    Frances C. Moore

    2009-03-01

    Full Text Available Air pollutants such as tropospheric ozone and black carbon (soot also contribute to the greenhouse effect. Black carbon is thought to be the second or third most important anthropogenic contributor to global warming, while troposheric ozone is the fourth most important. Both are also major components of indoor and outdoor air pollution. This paper reviews the existing literature of the health, economic, and climatic impacts of tropospheric ozone and black carbon emissions, together with mitigation options. The local nature of many of the impacts, combined with their short atmospheric lifetime and the existence of cost-effective abatement technologies that are already widely deployed in developed countries means reducing these emissions provides a highly climatically-effective mitigation option that is also appropriate to the development strategy of industrializing countries.

  8. Ultralow frequency acoustic resonances and its potential for mitigating tsunami wave formation

    CERN Document Server

    Estrada, Hector

    2012-01-01

    Bubbles display astonishing acoustical properties since they are able to absorb and scatter large amounts of energy coming from waves whose wavelengths are two orders of magnitude larger than the bubble size. Thus, as the interaction distance between bubbles is much larger than the bubble size, clouds of bubbles exhibit collective oscillations which can scatter acoustic waves three orders magnitude larger than the bubble size. Here we propose bubble based systems which resonate at frequencies that match the time scale relevant for seismogenic tsunami wave generation and may mitigate the devastating effects of tsunami waves. Based on a linear approximation, our na\\"ive proposal may open new research paths towards the mitigation of tsunami waves generation.

  9. Potential Roles of Swedish Forestry in the Context of Climate Change Mitigation

    Directory of Open Access Journals (Sweden)

    Tomas Lundmark

    2014-03-01

    Full Text Available In Sweden, where forests cover more than 60% of the land area, silviculture and the use of forest products by industry and society play crucial roles in the national carbon balance. A scientific challenge is to understand how different forest management and wood use strategies can best contribute to climate change mitigation benefits. This study uses a set of models to analyze the effects of different forest management and wood use strategies in Sweden on carbon dioxide emissions and removals through 2105. If the present Swedish forest use strategy is continued, the long-term climate change mitigation benefit will correspond to more than 60 million tons of avoided or reduced emissions of carbon dioxide annually, compared to a scenario with similar consumption patterns in society but where non-renewable products are used instead of forest-based products. On average about 470 kg of carbon dioxide emissions are avoided for each cubic meter of biomass harvested, after accounting for carbon stock changes, substitution effects and all emissions related to forest management and industrial processes. Due to Sweden’s large export share of forest-based products, the climate change mitigation effect of Swedish forestry is larger abroad than within the country. The study also shows that silvicultural methods to increase forest biomass production can further reduce net carbon dioxide emissions by an additional 40 million tons of per year. Forestry’s contribution to climate change mitigation could be significantly increased if management of the boreal forest were oriented towards increased biomass production and if more wood were used to substitute fossil fuels and energy-intensive materials.

  10. Greenhouse gas energy scenarios for Mexico in year 2020, and mitigation potential of renewable technologies

    Energy Technology Data Exchange (ETDEWEB)

    Sheinbaum, Claudia; Robles, Guillermo; Rodriguez V, Luis [Instituto de Ingenieria de la UNAM, Mexico, D.F. (Mexico); Massera, Omar [UNAM, Michoacan (Mexico)

    2000-07-01

    This paper presents the structure of the Mexican Energy-Emission Scenario Model (MEESM). In explains the importance of developing a bottom-up model for GHG mitigation assessment in Mexico. Also, the paper presents results of CO{sub 2} mitigation scenarios for year 2020 for five renewable energy technologies: solar water heaters, geothermal, biomass, mini/micro hydro and wind power generation. The paper concludes by discussing the importance of simulation accounting bottom-up models as tools for GHG mitigation policies. [Spanish] Este articulo presenta la estructura del Modelo de Escenario de Emision de Energia Mexicano (MEESM). En el se explica la importancia de desarrollar un modelo organizacional de abajo hacia arriba para la evaluacion de la mitigacion del efecto invernadero en Mexico. El articulo presenta tambien los resultados de los escenarios de mitigacion de CO{sub 2} para el ano 2020 utilizando cinco tecnologias de energia renovable: calentadores solares de agua, geotermia, biomasa, y mini/micro generacion de energia por agua y viento. El articulo concluye con el analisis de la importancia de la simulacion tomando en cuenta modelos organizacionales de abajo hacia arriba como herramientas para las politicas de mitigacion del efecto invernadero.

  11. Mitigating nitrous oxide emissions from corn cropping systems in the Midwestern U.S.: potential and data gaps.

    Science.gov (United States)

    Decock, Charlotte

    2014-04-15

    One of the unintended nitrogen (N)-loss pathways from cropland is the emission of nitrous oxide (N2O), a potent greenhouse gas and ozone depleting substance. This study explores the potential of alternative agronomic management practices to mitigate N2O emissions from corn cropping systems in major corn producing regions in the U.S. and Canada, using meta-analysis. The use of the urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT) in combination with the nitrification inhibitor Dicyandiamide (DCD) was the only management strategy that consistently reduced N2O emissions, but the number of observations underlying this effect was relatively low. Manure application caused higher N2O emissions compared to the use of synthetic fertilizer N. This warrants further investigation in appropriate manure N-management, particularly in the Lake States where manure application is common. The N2O response to increasing N-rate varied by region, indicating the importance of region-specific approaches for quantifying N2O emissions and mitigation potential. In general, more data collection on side-by-side comparisons of common and alternative management practices, especially those pertaining to N-placement, N-timing, and N-source, in combination with biogeochemical model simulations, will be needed to further develop and improve N2O mitigation strategies for corn cropping systems in the major corn producing regions in the U.S.

  12. Gas hydrates: entrance to a methane age or climate threat?

    Energy Technology Data Exchange (ETDEWEB)

    Krey, Volker; Nakicenovic, Nebojsa; Grubler, Arnulf; O' Neill, Brian; Riahi, Keywan [International Institute for Applied Systems Analysis (IIASA), Schlossplatz 1, 2361 Laxenburg (Austria); Canadell, Josep G [Global Carbon Project, CSIRO Marine and Atmospheric Research, GPO Box 3023, Canberra, ACT 2601 (Australia); Abe, Yuichi [Social Science Consulting Unit, Japan Nus Co. Ltd, Loop-X Building 7F, 9-15 Kaigan 3-Chome, Minato-ku, Tokyo 108-0022 (Japan); Andruleit, Harald [Bundesanstalt fuer Geowissenschaften und Rohstoffe (BGR), Stilleweg 2, 30655 Hannover (Germany); Archer, David [Department of the Geophysical Sciences at the University of Chicago, 5734 South Ellis Avenue, Chicago, IL 60637 (United States); Hamilton, Neil T M [WWF International Arctic Programme, Kristian Augusts gate 7a, 0130 Oslo (Norway); Johnson, Arthur [Hydrate Energy International, 612 Petit Berdot Drive, Kenner, LA 70065 (United States); Kostov, Veselin [Department of Physics and Astronomy, Johns Hopkins University, 3400 N Charles Street Baltimore, MD 21218 (United States); Lamarque, Jean-Francois [Atmospheric Chemistry Division, National Center for Atmospheric Research (NCAR), PO Box 3000, Boulder, CO 80307 (United States); Langhorne, Nicholas [US Office of Naval Research Global, Edison House, 223 Old Marylebone Road, London (United Kingdom); Nisbet, Euan G [Department of Geology, Royal Holloway, University of London, Egham, Surrey TW20 0EX (United Kingdom); Riedel, Michael [Earth and Planetary Sciences, McGill University, 3450 University Street, Montreal, QC, H3A 2A7 (Canada); Wang Weihua [Computer Network Information Center, Chinese Academy of Sciences, No. 4, 4th South Street, ZhongGuanCun, PO Box 349, Haidian District, Beijing 100080 (China); Yakushev, Vladimir, E-mail: krey@iiasa.ac.a [Gazprom VNIIGAZ LLC, Razvilka, Leninsky District, Moscow Region, 142717 (Russian Federation)

    2009-09-15

    Methane hydrates, ice-like compounds in which methane is held in crystalline cages formed by water molecules, are widespread in areas of permafrost such as the Arctic and in sediments on the continental margins. They are a potentially vast fossil fuel energy source but, at the same time, could be destabilized by changing pressure-temperature conditions due to climate change, potentially leading to strong positive carbon-climate feedbacks. To enhance our understanding of both the vulnerability of and the opportunity provided by methane hydrates, it is necessary (i) to conduct basic research that improves the highly uncertain estimates of hydrate occurrences and their response to changing environmental conditions, and (ii) to integrate the agendas of energy security and climate change which can provide an opportunity for methane hydrates-in particular if combined with carbon capture and storage-to be used as a 'bridge fuel' between carbon-intensive fossil energies and zero-emission energies. Taken one step further, exploitation of dissociating methane hydrates could even mitigate against escape of methane to the atmosphere. Despite these opportunities, so far, methane hydrates have been largely absent from energy and climate discussions, including global hydrocarbon assessments and the Fourth Assessment Report of the Intergovernmental Panel on Climate Change.

  13. Mitigation potential of horizontal ground coupled heat pumps for current and future climatic conditions: UK environmental modelling and monitoring studies

    Science.gov (United States)

    García González, Raquel; Verhoef, Anne; Vidale, Pier Luigi; Gan, Guohui; Wu, Yupeng; Hughes, Andrew; Mansour, Majdi; Blyth, Eleanor; Finch, Jon; Main, Bruce

    2010-05-01

    An increased uptake of alternative low or non-CO2 emitting energy sources is one of the key priorities for policy makers to mitigate the effects of environmental change. Relatively little work has been undertaken on the mitigation potential of Ground Coupled Heat Pumps (GCHPs) despite the fact that a GCHP could significantly reduce CO2 emissions from heating systems. It is predicted that under climate change the most probable scenario is for UK temperatures to increase and for winter rainfall to become more abundant; the latter is likely to cause a general rise in groundwater levels. Summer rainfall may reduce considerably, while vegetation type and density may change. Furthermore, recent studies underline the likelihood of an increase in the number of heat waves. Under such a scenario, GCHPs will increasingly be used for cooling as well as heating. These factors will affect long-term performance of horizontal GCHP systems and hence their economic viability and mitigation potential during their life span ( 50 years). The seasonal temperature differences encountered in soil are harnessed by GCHPs to provide heating in the winter and cooling in the summer. The performance of a GCHP system will depend on technical factors (heat exchanger (HE) type, length, depth, and spacing of pipes), but also it will be determined to a large extent by interactions between the below-ground parts of the system and the environment (atmospheric conditions, vegetation and soil characteristics). Depending on the balance between extraction and rejection of heat from and to the ground, the soil temperature in the neighbourhood of the HE may fall or rise. The GROMIT project (GROund coupled heat pumps MITigation potential), funded by the Natural Environment Research Council (UK), is a multi-disciplinary research project, in collaboration with EarthEnergy Ltd., which aims to quantify the CO2 mitigation potential of horizontal GCHPs. It considers changing environmental conditions and combines

  14. Comparing Top-down and Bottom-up Estimates of Methane Emissions across Multiple U.S. Basins Provides Insights into National Oil and Gas Emissions and Mitigation Strategies

    Science.gov (United States)

    Hamburg, S.; Alvarez, R.; Lyon, D. R.; Zavala-Araiza, D.

    2016-12-01

    Several recent studies quantified regional methane emissions in U.S. oil and gas (O&G) basins using top-down approaches such as airborne mass balance measurements. These studies apportioned total methane emissions to O&G based on hydrocarbon ratios or subtracting bottom-up estimates of other sources. In most studies, top-down estimates of O&G methane emissions exceeded bottom-up emission inventories. An exception is the Barnett Shale Coordinated Campaign, which found agreement between aircraft mass balance estimates and a custom emission inventory. Reconciliation of Barnett Shale O&G emissions depended on two key features: 1) matching the spatial domains of top-down and bottom-up estimates, and 2) accounting for fat-tail sources in site-level emission factors. We construct spatially explicit custom emission inventories for domains with top-down O&G emission estimates in eight major U.S. oil and gas production basins using a variety of data sources including a spatially-allocated U.S. EPA Greenhouse Gas Inventory, the EPA Greenhouse Gas Reporting Program, state emission inventories, and recently published measurement studies. A comparison of top-down and our bottom-up estimates of O&G emissions constrains the gap between these approaches and elucidates regional variability in production-normalized loss rates. A comparison of component-level and site-level emission estimates of production sites in the Barnett Shale region - where comprehensive activity data and emissions estimates are available - indicates that abnormal process conditions contribute about 20% of regional O&G emissions. Combining these two analyses provides insights into the relative importance of different equipment, processes, and malfunctions to emissions in each basin. These data allow us to estimate the U.S. O&G supply chain loss rate, recommend mitigation strategies to reduce emissions from existing infrastructure, and discuss how a similar approach can be applied internationally.

  15. Comprehensive radiative forcing assesment highlights trade-offs in climate mitigation potential of managed boreal forests

    Science.gov (United States)

    Kalliokoski, Tuomo; Berninger, Frank; Bäck, Jaana; Boy, Michael; Kuusinen, Nea; Mäkelä, Annikki; Matthies, Brent; Minkkinen, Kari; Mogensen, Ditte; Peltoniemi, Mikko; Sievänen, Risto; Zhou, Luxi; Vanhatalo, Anni; Valsta, Lauri; Nikinmaa, Eero

    2016-04-01

    Boreal forests have an important role in the mitigation of climate change. In this study we evaluated four key climate impacts of forest management: (1) carbon sequestration (in forest ecosystems and wood products), (2) surface albedo of forest area, (3) forest originating Secondary Organic Aerosols (SOA) and (4) avoided CO2-emissions from wood energy and product substitution. We calculated their net effect at both a single stand and regional level using Finland as a case study. We made analyses both in current climate up to a year 2050 and in the projected climate of year 2050. At the stand level, the carbon sequestration effect and avoided CO2 emissions due to substituted materials dominated in net RF in current climate. The warming effect of surface albedo of forest cover was lower or of same magnitude than cooling effect of SOAs. Together, the rarely considered SOAs and product substitution corresponded over 70% of the total cooling effect of forest cover. The cooling effect of net radiative forcing increased along the increasing site fertility. Although the carbon stocks of broadleaved trees were smaller than that of conifers their total radiative cooling effect was larger due to the integrated albedo and aerosol effects. In the projected climate of 2050, the radiative cooling of aerosols approached the level of forest carbon fixation. These results emphasize the need for holistic evaluation of climate impacts over simple carbon sequestration analysis to understand the role of forest management in climate change mitigation. Landscape level analyses emphasized the broad range of options to reach the cooling effect. The lowest harvest regime, 50% of current annual increment (CAI), yielded the largest cooling effect. Yet, harvests up to CAI produced only slightly less cooling RF if avoided emissions were considered. This result was highly sensitive to used substitution factors. Our result highlights that the combination of intensive harvests and the use of wood

  16. Influence of wastewater characteristics on methane potential in food-processing industry wastewaters

    DEFF Research Database (Denmark)

    Maya Altamira, Larisa; Baun, Anders; Angelidaki, Irini;

    2008-01-01

    ) were compared to the theoretical methane yields (Bo,th) in order to evaluate the biodegradability of the tested wastewaters and the influence of their physico-chemical characteristics. The analytical method applied to quantify the wastewaters’ organic content proved to influence the estimation...... yields; on the other hand, it was found that they were affected positively by concentrations of total inorganic carbon when wastewaters were 25% and 50% diluted and affected negatively by concentrations of total acetate when wastewaters were undiluted. Carbohydrate and protein concentrations affected...

  17. Implications of climate change predictions for UK cropping and prospects for possible mitigation: a review of challenges and potential responses.

    Science.gov (United States)

    Rial-Lovera, Karen; Davies, W Paul; Cannon, Nicola D

    2017-01-01

    The UK, like the rest of the world, is confronting the impacts of climate change. Further changes are expected and they will have a profound effect on agriculture. Future crop production will take place against increasing CO2 levels and temperatures, decreasing water availability, and increasing frequency of extreme weather events. This review contributes to research on agricultural practices for climate change, but with a more regional perspective. The present study explores climate change impacts on UK agriculture, particularly food crop production, and how to mitigate and build resilience to climate change by adopting and/or changing soil management practices, including fertilisation and tillage systems, new crop adoption and variety choice. Some mitigation can be adopted in the shorter term, such as changes in crop type and reduction in fertiliser use, but in other cases the options will need greater investment and longer adaptation period. This is the case for new crop variety development and deployment, and possible changes to soil cultivations. Uncertainty of future weather conditions, particularly extreme weather, also affect decision-making for adoption of practices by farmers to ensure more stable and sustainable production. Even when there is real potential for climate change mitigation, it can sometimes be more difficult to accomplish with certainty on-farm. Better future climate projections and long-term investments will be required to create more resilient agricultural systems in the UK in the face of climate change challenges. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  18. Potential for energy recovery and greenhouse gas mitigation from municipal solid waste using a waste-to-material approach.

    Science.gov (United States)

    Chen, Ying-Chu

    2016-12-01

    Energy recovery and greenhouse gas (GHG) emissions from wastes are getting noticed in recent years. This study evaluated the potential for energy recovery and GHG mitigation from municipal solid waste (MSW) with a waste-to-material (WTM) approach. Waste generated in Taiwan contains a large amount of paper, food waste, and plastics, which previously were mostly sent to waste-to-energy (WTE) plants for incineration. However, the mitigation of GHGs by the WTM approach has been especially successful in the recycling of metals (averaging 1.83×10(6)kgCO2-eq/year) and paper (averaging 7.38×10(5)kgCO2-eq/year). In addition, the recycling of paper (1.33×10(10)kWh) and plastics (1.26×10(10)kWh) has contributed greatly to energy saving. Both metal and glass are not suitable for incineration due to their low energy content. The volumes of paper and food waste contained in the MSW are positively related to the carbon concentration, which may contribute to increased GHGs during incineration. Therefore, the recycling of paper, metals, and food waste is beneficial for GHG mitigation. Measures to reduce GHGs were also suggested in this study. The development of the WTM approach may be helpful for the proper management of MSW with regards to GHG mitigation. The results of this study can be a successful example for other nations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Limited potential of no-till agriculture for climate change mitigation

    Science.gov (United States)

    Powlson, David S.; Stirling, Clare M.; Jat, M. L.; Gerard, Bruno G.; Palm, Cheryl A.; Sanchez, Pedro A.; Cassman, Kenneth G.

    2014-08-01

    The Emissions Gap Report 2013 from the United Nations Environment Programme restates the claim that changing to no-till practices in agriculture, as an alternative to conventional tillage, causes an accumulation of organic carbon in soil, thus mitigating climate change through carbon sequestration. But these claims ignore a large body of experimental evidence showing that the quantity of additional organic carbon in soil under no-till is relatively small: in large part apparent increases result from an altered depth distribution. The larger concentration near the surface in no-till is generally beneficial for soil properties that often, though not always, translate into improved crop growth. In many regions where no-till is practised it is common for soil to be cultivated conventionally every few years for a range of agronomic reasons, so any soil carbon benefit is then lost. We argue that no-till is beneficial for soil quality and adaptation of agriculture to climate change, but its role in mitigation is widely overstated.

  20. The potential of Indonesian mangrove forests for global climate change mitigation

    Science.gov (United States)

    Murdiyarso, Daniel; Purbopuspito, Joko; Kauffman, J. Boone; Warren, Matthew W.; Sasmito, Sigit D.; Donato, Daniel C.; Manuri, Solichin; Krisnawati, Haruni; Taberima, Sartji; Kurnianto, Sofyan

    2015-12-01

    Mangroves provide a wide range of ecosystem services, including nutrient cycling, soil formation, wood production, fish spawning grounds, ecotourism and carbon (C) storage. High rates of tree and plant growth, coupled with anaerobic, water-logged soils that slow decomposition, result in large long-term C storage. Given their global significance as large sinks of C, preventing mangrove loss would be an effective climate change adaptation and mitigation strategy. It has been reported that C stocks in the Indo-Pacific region contain on average 1,023 MgC ha-1 (ref. ). Here, we estimate that Indonesian mangrove C stocks are 1,083 +/- 378 MgC ha-1. Scaled up to the country-level mangrove extent of 2.9 Mha (ref. ), Indonesia’s mangroves contained on average 3.14 PgC. In three decades Indonesia has lost 40% of its mangroves, mainly as a result of aquaculture development. This has resulted in annual emissions of 0.07-0.21 Pg CO2e. Annual mangrove deforestation in Indonesia is only 6% of its total forest loss; however, if this were halted, total emissions would be reduced by an amount equal to 10-31% of estimated annual emissions from land-use sectors at present. Conservation of carbon-rich mangroves in the Indonesian archipelago should be a high-priority component of strategies to mitigate climate change.

  1. Japan's long-term energy outlook to 2050: Estimation for the potential of massive CO2 mitigation

    Energy Technology Data Exchange (ETDEWEB)

    Komiyama, Ryoichi

    2010-09-15

    This paper analyzes Japan's energy outlook and CO2 emissions to 2050. Scenario analysis reveals that Japan's CO2 emissions in 2050 could be potentially reduced by 58% from the emissions in 2005. For achieving this massive mitigation, it is required to reduce primary energy supply per GDP by 60% in 2050 from the 2005 level and to expand the share of non-fossil fuel in total supply to 50% by 2050. Concerning power generation mix, nuclear will account for 60%, renewable for 30% in 2050. For massive CO2 abatement, Japan should tackle technological and economic challenges for large-scale deployment of advanced technologies.

  2. Extensive management of field margins enhances their potential for off-site soil erosion mitigation.

    Science.gov (United States)

    Ali, Hamada E; Reineking, Björn

    2016-03-15

    Soil erosion is a widespread problem in agricultural landscapes, particularly in regions with strong rainfall events. Vegetated field margins can mitigate negative impacts of soil erosion off-site by trapping eroded material. Here we analyse how local management affects the trapping capacity of field margins in a monsoon region of South Korea, contrasting intensively and extensively managed field margins on both steep and shallow slopes. Prior to the beginning of monsoon season, we equipped a total of 12 sites representing three replicates for each of four different types of field margins ("intensive managed flat", "intensive managed steep", "extensive managed flat" and "extensive managed steep") with Astroturf mats. The mats (n = 15/site) were placed before, within and after the field margin. Sediment was collected after each rain event until the end of the monsoon season. The effect of management and slope on sediment trapping was analysed using linear mixed effects models, using as response variable either the sediment collected within the field margin or the difference in sediment collected after and before the field margin. There was no difference in the amount of sediment reaching the different field margin types. In contrast, extensively managed field margins showed a large reduction in collected sediment before and after the field margins. This effect was pronounced in steep field margins, and increased with the size of rainfall events. We conclude that a field margin management promoting a dense vegetation cover is a key to mitigating negative off-site effects of soil erosion in monsoon regions, particularly in field margins with steep slopes.

  3. Disease dynamics and potential mitigation among restored and wild staghorn coral, Acropora cervicornis

    Directory of Open Access Journals (Sweden)

    Margaret W. Miller

    2014-08-01

    Full Text Available The threatened status (both ecologically and legally of Caribbean staghorn coral, Acropora cervicornis, has prompted rapidly expanding efforts in culture and restocking, although tissue loss diseases continue to affect populations. In this study, disease surveillance and histopathological characterization were used to compare disease dynamics and conditions in both restored and extant wild populations. Disease had devastating effects on both wild and restored populations, but dynamics were highly variable and appeared to be site-specific with no significant differences in disease prevalence between wild versus restored sites. A subset of 20 haphazardly selected colonies at each site observed over a four-month period revealed widely varying disease incidence, although not between restored and wild sites, and a case fatality rate of 8%. A tropical storm was the only discernable environmental trigger associated with a consistent spike in incidence across all sites. Lastly, two field mitigation techniques, (1 excision of apparently healthy branch tips from a diseased colony, and (2 placement of a band of epoxy fully enclosing the diseased margin, gave equivocal results with no significant benefit detected for either treatment compared to controls. Tissue condition of associated samples was fair to very poor; unsuccessful mitigation treatment samples had severe degeneration of mesenterial filament cnidoglandular bands. Polyp mucocytes in all samples were infected with suspect rickettsia-like organisms; however, no bacterial aggregates were found. No histological differences were found between disease lesions with gross signs fitting literature descriptions of white-band disease (WBD and rapid tissue loss (RTL. Overall, our results do not support differing disease quality, quantity, dynamics, nor health management strategies between restored and wild colonies of A. cervicornis in the Florida Keys.

  4. Disease dynamics and potential mitigation among restored and wild staghorn coral, Acropora cervicornis.

    Science.gov (United States)

    Miller, Margaret W; Lohr, Kathryn E; Cameron, Caitlin M; Williams, Dana E; Peters, Esther C

    2014-01-01

    The threatened status (both ecologically and legally) of Caribbean staghorn coral, Acropora cervicornis, has prompted rapidly expanding efforts in culture and restocking, although tissue loss diseases continue to affect populations. In this study, disease surveillance and histopathological characterization were used to compare disease dynamics and conditions in both restored and extant wild populations. Disease had devastating effects on both wild and restored populations, but dynamics were highly variable and appeared to be site-specific with no significant differences in disease prevalence between wild versus restored sites. A subset of 20 haphazardly selected colonies at each site observed over a four-month period revealed widely varying disease incidence, although not between restored and wild sites, and a case fatality rate of 8%. A tropical storm was the only discernable environmental trigger associated with a consistent spike in incidence across all sites. Lastly, two field mitigation techniques, (1) excision of apparently healthy branch tips from a diseased colony, and (2) placement of a band of epoxy fully enclosing the diseased margin, gave equivocal results with no significant benefit detected for either treatment compared to controls. Tissue condition of associated samples was fair to very poor; unsuccessful mitigation treatment samples had severe degeneration of mesenterial filament cnidoglandular bands. Polyp mucocytes in all samples were infected with suspect rickettsia-like organisms; however, no bacterial aggregates were found. No histological differences were found between disease lesions with gross signs fitting literature descriptions of white-band disease (WBD) and rapid tissue loss (RTL). Overall, our results do not support differing disease quality, quantity, dynamics, nor health management strategies between restored and wild colonies of A. cervicornis in the Florida Keys.

  5. Atmospheric methane removal by methane-oxidizing bacteria immobilized on porous building materials

    NARCIS (Netherlands)

    Ganendra, G; De Muynck, W; Ho, A.; Hoefman, S.; De Vos, P.; Boeckx, P.; Boon, N.

    2014-01-01

    Biological treatment using methane-oxidizing bacteria (MOB) immobilized on six porous carrier materials have been used to mitigate methane emission. Experiments were performed with different MOB inoculated in building materials at high (similar to 20 % (v/v)) and low (similar to 100 ppmv) methane

  6. Coalbed methane : Canadian potential : is it analogous to the U.S.

    Energy Technology Data Exchange (ETDEWEB)

    Gatens, M. [MGV Energy Inc., Calgary, AB (Canada)

    2003-07-01

    A historical review of coalbed methane (CBM) evolution in North America was presented with reference to development in Canada and recent advances in technology. The Canadian CBM resource is estimated at several hundred Tcf. It was noted that the characteristics of CBM development in Canada are unique. The issues faced in Canadian CBM basins are different from those in the United States. Non-technical issues, such as CBM ownership and environmental concerns in the United States are having a growing impact on the pace of Canadian CBM development. For example, the problem of handling produced water in the Powder River Basin is inhibiting Canadian CBM development. However, the author pointed out that there is no produced water in Canadian CBM development. The author emphasized that stakeholders should be educated in Canadian CBM facts to ensure that CBM development in Canada proceeds responsibly, without confusion of U.S. issues that are non-issues in Canada.

  7. Potential of Ni supported on clinoptilolite catalysts for carbon dioxide reforming of methane

    Energy Technology Data Exchange (ETDEWEB)

    Nimwattanakul, Weetima; Luengnaruemitchai, Apanee; Jitkarnka, Sirirat [The Petroleum and Petrochemical College, Chulalongkorn University, Bangkok 10330 (Thailand)

    2006-01-15

    Carbon dioxide reforming of methane to synthesis gas has been investigated with Ni-supported clinoptilolite catalysts. The catalysts were prepared by using the incipient wetness impregnation method. The catalytic activity of Ni supported on clinoptilolite with varying Ni loadings was determined and the results showed that at 700{sup o}C, 8wt% Ni/clinoptilolite gave the highest activity. It exhibited not only the highest activity and selectivity but also remarkable stability. Moreover, both the activity and stability of this catalyst were observed to vary with the Zr content, exhibiting a maximum at a composition of 2% Zr. The amount of carbonaceous deposits on the spent catalysts was further investigated by temperature-programmed oxidation (TPO) and thermogravimetric analyzer (TGA) studies. (author)

  8. Methane emission from rice fields in relation to management of irrigation water.

    Science.gov (United States)

    Khosa, Maninder Kaur; Sidhu, B S; Benbi, D K

    2011-03-01

    A field experiment was conducted for two years to find out best water management practice to mitigate methane emission from the rice-fields. Continuously flooded conditions yielded two major flushes of methane emission and on an average resulted in relatively higher rate of methane emission (2.20 and 1.30 mg m(-2) hr(-1), respectively in 2005 and 2006) during the kharif season. The methane flux was reduced to half (1.02 and 0.47 mg m(-2) hr(-1), respectively in 2005 and 2006) when rice fields were irrigated 2-3 days after infiltration of flood water into the soil. Irrigating the field at 0.15 bar matric potential reduced seasonal methane flux by 60% (0.99 and 0.41 mg m(-2) hr(-1), respectively in 2005 and 2006) as compared to completely flooded conditions, without any decline in grain yield (60 q ha(-1)).

  9. Fortification of dried distillers grains plus solubles with grape seed meal in the diet modulates methane mitigation and rumen microbiota in Rusitec.

    Science.gov (United States)

    Khiaosa-Ard, R; Metzler-Zebeli, B U; Ahmed, S; Muro-Reyes, A; Deckardt, K; Chizzola, R; Böhm, J; Zebeli, Q

    2015-04-01

    The role of dried distillers grains plus solubles (DDGS) and associative effects of different levels of grape seed meal (GSM) fortified in DDGS, used as both protein and energy sources in the diet, on ruminal fermentation and microbiota were investigated using rumen-simulation technique. All diets consisted of hay and concentrate mixture with a ratio of 48:52 [dry matter (DM) basis], but were different in the concentrate composition. The control diet contained soybean meal (13.5% of diet DM) and barley grain (37%), whereas DDGS treatments, unfortified DDGS (19.5% of diet DM), or DDGS fortified with GSM, either at 1, 5, 10, or 20% were used entirely in place of soybean meal and part of barley grain at a 19.5 to 25% inclusion level. All diets had similar DM, organic matter, and crude protein contents, but consisted of increasing neutral detergent fiber and decreasing nonfiber carbohydrates levels with DDGS-GSM inclusion. Compared with the soy-based control diet, the unfortified DDGS treatment elevated ammonia concentration (19.1%) of rumen fluid associated with greater crude protein degradation (~19.5%). Methane formation decreased with increasing GSM fortification levels (≥ 5%) in DDGS by which the methane concentration significantly decreased by 18.9 to 23.4 and 12.8 to 17.6% compared with control and unfortified DDGS, respectively. Compared with control, unfortified DDGS decreased butyrate proportion, and GSM fortification in the diet further decreased this variable. The proportions of genus Prevotella and Clostridium cluster XIVa were enhanced by the presence of DDGS without any associative effect of GSM fortification. The abundance of methanogenic archaea was similar, but their composition differed among treatments; whereas Methanosphaera spp. remained unchanged, proportion of Methanobrevibacter spp. decreased in DDGS-based diets, being the lowest with 20% GSM inclusion. The abundance of Ruminococcus flavefaciens, anaerobic fungi, and protozoa were decreased

  10. Sulfide oxidation and nitrate reduction for potential mitigation of H2S in landfills.

    Science.gov (United States)

    Fang, Yuan; Du, Yao; Feng, Huan; Hu, Li-Fang; Shen, Dong-Sheng; Long, Yu-Yang

    2015-04-01

    Because H2S emitted by landfill sites has seriously endangered human health, its removal is urgent. H2S removal by use of an autotrophic denitrification landfill biocover has been reported. In this process, nitrate-reducing and sulfide-oxidizing bacteria use a reduced sulfur source as electron donor when reducing nitrate to nitrogen gas and oxidizing sulfur compounds to sulfate. The research presented here was performed to investigate the possibility of endogenous mitigation of H2S by autotrophic denitrification of landfill waste. The sulfide oxidation bioprocess accompanied by nitrate reduction was observed in batch tests inoculated with mineralized refuse from a landfill site. Repeated supply of nitrate resulted in rapid oxidation of the sulfide, indicating that, to a substantial extent, the bioprocess may be driven by functional microbes. This bioprocess can be realized under conditions suitable for the autotrophic metabolic process, because the process occurred without addition of acetate. H2S emissions from landfill sites would be substantially reduced if this bioprocess was introduced.

  11. Fossil energy savings and GHG mitigation potentials of ethanol as a gasoline substitute in Thailand

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Thu Lan T. [The Joint Graduate School of Energy and Environment, King Mongkut' s University of Technology Thonburi, Bangkok (Thailand); Gheewala, Shabbir H. [The Joint Graduate School of Energy and Environment, King Mongkut' s University of Technology Thonburi, Bangkok (Thailand)]. E-mail: shabbir_g@jgsee.kmutt.ac.th; Garivait, Savitri [The Joint Graduate School of Energy and Environment, King Mongkut' s University of Technology Thonburi, Bangkok (Thailand)

    2007-10-15

    One of the Thai government's measures to promote ethanol use is excise tax exemption, making gasohol cheaper than gasoline. The policy in favour of biofuels is being supported by their contribution to fossil energy savings and greenhouse gas (GHG) mitigation. An analysis of energy balance (EnB), GHG balance and GHG abatement cost has been done to evaluate molasses-based ethanol (MoE) in Thailand. A positive EnB of 19.2 MJ/L implies that MoE is a good substitute for gasoline, effective in fossil energy savings. GHG balance assessment based on the baseline scenario shows that emissions are most likely to increase with the substitution. Scenarios using biogas captured from spent wash treatment and rice husk to substitute coal used in ethanol conversion give encouraging results in improving the GHG balance. However, the higher price of MoE over gasoline currently has resulted in high GHG abatement costs, even under the best-case scenario. Compared to the many other climate strategies relevant to Thailand, MoE is much less cost effective. Governed by the rule of supply and demand, a strong fluctuation in molasses price is considered the main cause of volatile MoE price. Once supplies are stable, the trend of price drops would make MoE a reasonable option for national climate policy.

  12. Potencial de emissão de metano em lavouras de arroz irrigado Methane emission potential in flooded rice fields

    Directory of Open Access Journals (Sweden)

    Dirceu Agostinetto

    2002-12-01

    responsible for such phenomenon. The main gases that cause the greenhouse effect are carbon dioxide (CO2, methane (CH4, nitrous oxide (N2O, and chlorofluorocarbons (CFCs. Methane stands out amongst them by the amount produced and by its activity in the absorbing atmospheric heat. The main methane producing sources are soils naturally flooded or cultivated under flooding conditions, which represent approximately 40% of the total methane emitted; from this amount, 37% is emitted by rice cultivated under flooding conditions. In this context, the present review has as main purposes to describe processes responsible for methane production and emission, as well as to discuss management practices and rice plant characteristics which affect emission of this gas. From the total methane originated in rice fields during its growth cycle, between 60 to 90% comes from rice plants. Although methane is not the main gas responsible for the greenhouse effect and rice crop does not represent the main methane source, the reduction in the emission could be accomplished through changes in rice cultural practices. Amongst alternatives that can be worked out are management of irrigation water and fertilizer applied, and cropping of rice cultivars that present lower number of aerenchyma and lower biomass production, whereas maintaining rice grain yields potential.

  13. Synergies between mitigation of, and adaptation to, climate change in agriculture

    DEFF Research Database (Denmark)

    Smith, P; Olesen, Jørgen E

    2010-01-01

    year is equivalent to 420 000, 130 000 and 32 000 million US$/yr for C prices of 100, 50 and 20 US$/t CO2 equiv, respectively. From both the mitigation and economic perspectives, we cannot afford to miss out on this mitigation potential. The challenge of agriculture within the climate change context...... is two-fold, both to reduce emissions and to adapt to a changing and more variable climate. The primary aim of the mitigation options is to reduce emissions of methane or nitrous oxide or to increase soil carbon storage. All the mitigation options, therefore, affect the carbon and/or nitrogen cycle...... through adding crop residues and manure to arable soils or by adding diversity to the crop rotations. Though some mitigation measures may have negative impacts on the adaptive capacity of farming systems, most categories of adaptation options for climate change have positive impacts on mitigation...

  14. Estimating urban trees and carbon stock potentials for mitigating climate change in Lagos: Case of Ikeja Government Reserved Area (GRA)

    Science.gov (United States)

    Elias, P. O.; Faderin, A.

    2014-12-01

    Urban trees are a component of the urban infrastructure which offers diverse services including environmental, aesthetic and economic. The accumulation of carbon in the atmosphere resulting from the indiscriminate distribution of human populations and urban activities with the unsustainable consumption of natural resources contributes to global environmental change especially in coastal cities like Lagos. Carbon stocks and sequestration by urban trees are increasingly recognized to play significant roles for mitigating climate change. This paper focuses on the estimation of carbon stock and sequestration through biomass estimation and quantification in Ikeja GRA, Lagos. Ikeja possesses a characteristic feature as a microcosm of Lagos due to the wide range of land uses. A canopy assessment of tree population was carried out using itree canopy software. A GPS survey was used to collect an inventory of all trees showing their location, spatial distribution and other attributes. The analysis of the carbon storage and sequestration potential of both actual and potential tree planting sites involved biomass estimations from tree allometry equations. Trees were identified at species level and measurements of their dendrometric values were recorded and integrated into the GIS database to estimate biomass of trees and carbon storage. The trees in the study area were estimated to have a biomass of 441.9 mg and carbon storage of 221.395 kg/tree. By considering the potential tree planting sites the estimated carbon stored increased to 11,352.73 kg. Carbon sequestration value in the study area was found to be 1.6790 tonnes for the existing trees and 40.707 tonnes for the potential tree planting sites (PTPS). The estimation of carbon storage and sequestration values of trees are important incentives for carbon accounting/footprints and monitoring of climate change mitigation which has implications for evaluation and monitoring of urban ecosystem.

  15. Characterisation of the biochemical methane potential (BMP) of individual material fractions in Danish source-separated organic household waste

    DEFF Research Database (Denmark)

    Naroznova, Irina; Møller, Jacob; Scheutz, Charlotte

    2016-01-01

    This study is dedicated to characterising the chemical composition and biochemical methane potential (BMP) of individual material fractions in untreated Danish source-separated organic household waste (SSOHW). First, data on SSOHW in different countries, available in the literature, were evaluated...... and then, secondly, laboratory analyses for eight organic material fractions comprising Danish SSOHW were conducted. No data were found in the literature that fully covered the objectives of the present study. Based on laboratory analyses, all fractions were assigned according to their specific properties...... in Denmark (untreated) was calculated, and the BMP contribution of the individual material fractions was then evaluated. Material fractions of the two general waste types, defined as "food waste" and "fibre-rich waste," were found to be anaerobically degradable with considerable BMP. Material degradability...

  16. The Pepcon Disaster-Causative Factors and potential Preventive and Mitigative Measures

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, H E; Alvares, N J

    2003-07-25

    On May 4, 1988, the PEPCON plant experienced three major and several smaller explosions that caused over $70 million in property damage and caused two deaths. The PEPCON plant produced Ammonium Perchlorate (AP), a major ingredient for rocket fuel. The PEPCON plant and the nearby Kidd Marshmallow plant were totally destroyed by the detonations. The initiating event for the explosions was a fire that originated in the Batch Dryer Building and spread to adjacent storage. Several factors combined to cause the AP in the major storage fields to detonate, the most important being lack of adequate separation between storage units. Welding and flame cutting procedure with poor fire watch protocol was the prime candidate for fire ignition. There were no automatic fire suppression systems at the plant. Buildings including the Batch Dryer Building were made of combustible building material (fiberglass). There was poor housekeeping and no control of AP dust generation. AP was stored in combustible polyethylene drums, aluminum tote bins, 30-gallon steel storage drums and fiber reinforced tote bags. There were high-density storage practices. In addition, a contributing factor to the rapid fire-spread was that the wind that day was blowing directly from the batch dryer building to the storage areas. This paper claims that if codes, standards, and well-known hazard identification safety techniques were implemented at PEPCON, then the disaster would have been averted. A limited scope probabilistic risk assessment was conducted to establish the effectiveness of various preventive and mitigative features that could have been deployed to avert the disaster. The major hazard at the PEPCON site was fire and explosion involving the processing, production and storage of AP, which was then and is currently stored as a class 4 oxidizer. Since minute quantities of contamination can cause AP to be detonable by shock, there has been an ongoing debate concerning its reclassification to a class

  17. Potential and economic efficiency of using reduced tillage to mitigate climate effects in Danish agriculture

    DEFF Research Database (Denmark)

    Zandersen, Marianne; Jørgensen, Sisse Liv; Nainggolan, Doan

    2016-01-01

    and land owners’ objectives and preferences in terms of participating in initiatives to increase SOC. We map the carbon sequestration potential under different scenarios, value the potential sequestered carbon in terms of marginal costs of using voluntary agreements with agricultural land managers...

  18. Retrieval of Methane Source Strengths in Europe Using a Simple Modeling Approach to Assess the Potential of Spaceborne Lidar Observations

    Science.gov (United States)

    Weaver, C.; Kiemle, C.; Kawa, S. R.; Aalto, T.; Necki, J.; Steinbacher, M.; Arduini, J.; Apadula, F.; Berkhout, H.; Hatakka, J.

    2014-01-01

    We investigate the sensitivity of future spaceborne lidar measurements to changes in surface methane emissions. We use surface methane observations from nine European ground stations and a Lagrangian transport model to infer surface methane emissions for 2010. Our inversion shows the strongest emissions from the Netherlands, the coal mines in Upper Silesia, Poland, and wetlands in southern Finland. The simulated methane surface concentrations capture at least half of the daily variability in the observations, suggesting that the transport model is correctly simulating the regional transport pathways over Europe. With this tool we can test whether proposed methane lidar instruments will be sensitive to changes in surface emissions. We show that future lidar instruments should be able to detect a 50% reduction in methane emissions from the Netherlands and Germany, at least during summer.

  19. Statistical characterization of trapped bubbles in subarctic lake ice: Potential implications for methane emissions

    Science.gov (United States)

    Wik, M.; Crill, P. M.; Bastviken, D.; Danielsson; Norbäck, E.

    2010-12-01

    Methane (CH4) emissions from northern lakes to the atmosphere are highly uncertain but estimated to increase due to arctic climate change and subsequent permafrost thaw and sediment warming. A large amount of CH4, if not the most, is thought to be released through ebullition (bubbling), a pathway with extreme spatial patchiness that challenges the accuracy of measurements and budget extrapolations. The spatial variability of ebullition can be assessed on northern lakes because bubbles are trapped in the ice during winter. This study statistically characterized trapped bubbles over various depths across two ice covered subarctic lakes in a changing discontinuous permafrost landscape in northern Sweden. Observations were made through a 0.64 m2 quadrat that was placed every third meter along a large number of randomly distributed transects. This stratified random sampling design combined with a digital image processing technique determined that bubble patterns on average covered up to 7.7% of the lake area and were dominated by ebullition from frequently occurring but highly spatially dispersed point sources with variabilities of up to 1056%. Bubble frequency differed significantly between early and late season lake ice, between the two lakes and among different zones within each lake (ptransects to examine the patchiness of bubbles with high precision. Thus, the number and variability of bubbles observed along a small number of transects will most likely be unsuitable variables in large scale estimates and extrapolations aiming to reduce uncertainties in the budget of atmospheric CH4.

  20. Intensive Ammonia and Methane Oxidation in Organic Liquid Manure Crusts

    DEFF Research Database (Denmark)

    Nielsen, Daniel Aagren; Nielsen, Lars Peter; Schramm, Andreas;

    of the crusts. PCR targeting the unique methane and ammonia monooxygenases were applied together with FISH to detect the presence of the two bacterial groups. Potential activity was assessed by short term slurry incubations of crust samples while monitoring NO2- production or CH4 consumption. Crusts were...... also CH4 emission mitigation, an organic surface crust can be effective if populations of MOB and AOB are allowed to build up....

  1. Monitoring and mitigating measures to reduce potential impacts of oil and gas exploration and development on bears in the Inuvik region

    Energy Technology Data Exchange (ETDEWEB)

    Branigan, M. [Government of the Northwest Territories, Inuvik, NT (Canada). Dept. of Environment and Natural Resources

    2007-07-01

    The Inuvik Region consists of the Northwest Territories portion of the Inuvialuit Settlement Region and the Gwich'in Settlement Area. The range of grizzly bears, polar bears and black bears extends to different parts of the region. The potential impact of development depends on the season of the development and the species of bear found in the footprint. As such, monitoring and mitigation measures should take this into consideration. This presentation focused on the potential impacts and current practices to monitor and mitigate the impacts in the region. Mitigation measures currently used include: communication with stakeholders; waste management guidelines; use of wildlife monitors to identify key habitat and den sites and to deter bears; minimum flight altitudes; and safety training. Suggestions for additional mitigation measures were also presented. figs.

  2. Methane Emissions from Upland Forests

    Science.gov (United States)

    Megonigal, Patrick; Pitz, Scott; Wang, Zhi-Ping

    2016-04-01

    Global budgets ascribe 4-10% of atmospheric methane sinks to upland soils and assume that soils are the sole surface for methane exchange between upland forests and the atmosphere. The dogma that upland forests are uniformly atmospheric methane sinks was challenged a decade ago by the discovery of abiotic methane production from plant tissue. Subsequently a variety of relatively cryptic microbial and non-microbial methane sources have been proposed that have the potential to emit methane in upland forests. Despite the accumulating evidence of potential methane sources, there are few data demonstrating actual emissions of methane from a plant surface in an upland forest. We report direct observations of methane emissions from upland tree stems in two temperate forests. Stem methane emissions were observed from several tree species that dominate a forest located on the mid-Atlantic coast of North America (Maryland, USA). Stem emissions occurred throughout the growing season while soils adjacent to the trees simultaneously consumed methane. Scaling fluxes by stem surface area suggested the forest was a net methane source during a wet period in June, and that stem emissions offset 5% of the soil methane sink on an annual basis. High frequency measurements revealed diurnal cycles in stem methane emission rates, pointing to soils as the methane source and transpiration as the most likely pathway for gas transport. Similar observations were made in an upland forest in Beijing, China. However, in this case the evidence suggested the methane was not produced in soils, but in the heartwood by microbial or non-microbial processes. These data challenge the concept that forests are uniform sinks of methane, and suggest that upland forests are smaller methane sinks than previously estimated due to stem emissions. Tree emissions may be particularly important in upland tropical forests characterized by high rainfall and transpiration.

  3. Density-Functional Theory with Dispersion-Correcting Potentials for Methane: Bridging the Efficiency and Accuracy Gap between High-Level Wave Function and Classical Molecular Mechanics Methods.

    Science.gov (United States)

    Torres, Edmanuel; DiLabio, Gino A

    2013-08-13

    Large clusters of noncovalently bonded molecules can only be efficiently modeled by classical mechanics simulations. One prominent challenge associated with this approach is obtaining force-field parameters that accurately describe noncovalent interactions. High-level correlated wave function methods, such as CCSD(T), are capable of correctly predicting noncovalent interactions, and are widely used to produce reference data. However, high-level correlated methods are generally too computationally costly to generate the critical reference data required for good force-field parameter development. In this work we present an approach to generate Lennard-Jones force-field parameters to accurately account for noncovalent interactions. We propose the use of a computational step that is intermediate to CCSD(T) and classical molecular mechanics, that can bridge the accuracy and computational efficiency gap between them, and demonstrate the efficacy of our approach with methane clusters. On the basis of CCSD(T)-level binding energy data for a small set of methane clusters, we develop methane-specific, atom-centered, dispersion-correcting potentials (DCPs) for use with the PBE0 density-functional and 6-31+G(d,p) basis sets. We then use the PBE0-DCP approach to compute a detailed map of the interaction forces associated with the removal of a single methane molecule from a cluster of eight methane molecules and use this map to optimize the Lennard-Jones parameters for methane. The quality of the binding energies obtained by the Lennard-Jones parameters we obtained is assessed on a set of methane clusters containing from 2 to 40 molecules. Our Lennard-Jones parameters, used in combination with the intramolecular parameters of the CHARMM force field, are found to closely reproduce the results of our dispersion-corrected density-functional calculations. The approach outlined can be used to develop Lennard-Jones parameters for any kind of molecular system.

  4. Energy Saving Potentials and Air Quality Benefits of Urban Heat Island Mitigation

    Energy Technology Data Exchange (ETDEWEB)

    Akbari, Hashem

    2005-08-23

    Urban areas tend to have higher air temperatures than their rural surroundings as a result of gradual surface modifications that include replacing the natural vegetation with buildings and roads. The term ''Urban Heat Island'' describes this phenomenon. The surfaces of buildings and pavements absorb solar radiation and become extremely hot, which in turn warm the surrounding air. Cities that have been ''paved over'' do not receive the benefit of the natural cooling effect of vegetation. As the air temperature rises, so does the demand for air-conditioning (a/c). This leads to higher emissions from power plants, as well as increased smog formation as a result of warmer temperatures. In the United States, we have found that this increase in air temperature is responsible for 5-10% of urban peak electric demand for a/c use, and as much as 20% of population-weighted smog concentrations in urban areas. Simple ways to cool the cities are the use of reflective surfaces (rooftops and pavements) and planting of urban vegetation. On a large scale, the evapotranspiration from vegetation and increased reflection of incoming solar radiation by reflective surfaces will cool a community a few degrees in the summer. As an example, computer simulations for Los Angeles, CA show that resurfacing about two-third of the pavements and rooftops with reflective surfaces and planting three trees per house can cool down LA by an average of 2-3K. This reduction in air temperature will reduce urban smog exposure in the LA basin by roughly the same amount as removing the basin entire onroad vehicle exhaust. Heat island mitigation is an effective air pollution control strategy, more than paying for itself in cooling energy cost savings. We estimate that the cooling energy savings in U.S. from cool surfaces and shade trees, when fully implemented, is about $5 billion per year (about $100 per air-conditioned house).

  5. Methane emissions from ruminants

    African Journals Online (AJOL)

    user

    2011-02-21

    Feb 21, 2011 ... Review. Livestock-environment interactions: Methane emissions from ruminants. Aluwong, T.1* ... perception of air quality by human neighbours.The three ... on the climate; the global warming potential of methane is. 21-times that of ... has serious impact on high atmosphere ozone formation. It is important ...

  6. Geothermal source potential and utilization for methane generation and alcohol production

    Energy Technology Data Exchange (ETDEWEB)

    Austin, J.C.

    1981-11-01

    A study was conducted to assess the technical and economic feasibility of integrating a geothermally heated anaerobic digester with a fuel alcohol plant and cattle feedlot. Thin stillage produced from the alcohol production process and manure collected from the cattle feedlot would be digested in anaerobic digesters to produce biogas, a mixture of methane and carbon dioxide, and residue. The energy requirements to maintain proper digester temperatures would be provided by geothermal water. The biogas produced in the digesters would be burned in a boiler to produce low-pressure steam which would be used in the alcohol production process. The alcohol plant would be sized so that the distiller's grains byproduct resulting from the alcohol production would be adequate to supply the daily cattle feed requirements. A portion of the digester residue would substitute for alfalfa hay in the cattle feedlot ration. The major design criterion for the integrated facilty was the production of adequate distiller's grain to supply the daily requirements of 1700 head of cattle. It was determined that, for a ration of 7 pounds of distiller's grain per head per day, a 1 million gpy alcohol facility would be required. An order-of-magnitude cost estimate was prepared for the proposed project, operating costs were calculated for a facility based on a corn feedstock, the economic feasibility of the proposed project was examined by calculating its simple payback, and an analysis was performed to examine the sensitivity of the project's economic viability to variations in feedstock costs and alcohol and distiller's grain prices.

  7. How to mitigate impacts of wind farms on bats? A review of potential conservation measures in the European context

    Energy Technology Data Exchange (ETDEWEB)

    Peste, Filipa, E-mail: filipapeste@gmail.com [Centre for Environmental and Marine Studies (CESAM) (Portugal); Department of Biology, University of Aveiro (Portugal); Paula, Anabela [Bioinsight - Ambiente e Biodiversidade, Lda. Lisboa (Portugal); Silva, Luís P. da [Centre for Environmental and Marine Studies (CESAM) (Portugal); Department of Biology, University of Aveiro (Portugal); MARE and CEF, Department of Life Sciences, University of Coimbra (Portugal); Bernardino, Joana; Pereira, Pedro [Bio3 - Estudos e Projectos em Biologia e Recursos Naturais, Lda. Almada (Portugal); Mascarenhas, Miguel [Bioinsight - Ambiente e Biodiversidade, Lda. Lisboa (Portugal); Costa, Hugo [Bio3 - Estudos e Projectos em Biologia e Recursos Naturais, Lda. Almada (Portugal); Vieira, José; Bastos, Carlos [Department of Electronics, Telecommunications and Informatics / IEETA, University of Aveiro (Portugal); Fonseca, Carlos [Centre for Environmental and Marine Studies (CESAM) (Portugal); Department of Biology, University of Aveiro (Portugal); Pereira, Maria João Ramos [Centre for Environmental and Marine Studies (CESAM) (Portugal); PPGBAN, Department of Zoology, Institute of Biosciences, Federal University of Rio Grande do Sul (Brazil); PPGEC, Federal University of Mato Grosso do Sul (Brazil)

    2015-02-15

    Wind energy is growing worldwide as a source of power generation. Bat assemblages may be negatively affected by wind farms due to the fatality of a significant number of individuals after colliding with the moving turbines or experiencing barotrauma. The implementation of wind farms should follow standard procedures to prevent such negative impacts: avoid, reduce and offset, in what is known as the mitigation hierarchy. According to this approach avoiding impacts is the priority, followed by the minimisation of the identified impacts, and finally, when residual negative impacts still remain, those must be offset or at least compensated. This paper presents a review on conservation measures for bats and presents some guidelines within the compensation scenario, focusing on negative impacts that remain after avoidance and minimisation measures. The conservation strategies presented aim at the improvement of the ecological conditions for the bat assemblage as a whole. While developed under the European context, the proposed measures are potentially applicable elsewhere, taking into consideration the specificity of each region in terms of bat assemblages present, landscape features and policy context regarding nature and biodiversity conservation and management. An analysis of potential opportunities and constraints arising from the implementation of offset/compensation programmes and gaps in the current knowledge is also considered. - Highlights: • Wind energy impacts bat populations in ways not yet fully understood. • As the use of windfarms is growing worldwide greater impacts on bat populations are also expected. • Mitigation hierarchy provides a way to reduce impacts from new wind farm facilities. • Compensation measures may be used to reduce the residual effects on bat populations. • Identify bats ecological needs and compensate according to the existing surroundings.

  8. Climate change mitigation: potential benefits and pitfalls of enhanced rock weathering in tropical agriculture.

    Science.gov (United States)

    Edwards, David P; Lim, Felix; James, Rachael H; Pearce, Christopher R; Scholes, Julie; Freckleton, Robert P; Beerling, David J

    2017-04-01

    Restricting future global temperature increase to 2°C or less requires the adoption of negative emissions technologies for carbon capture and storage. We review the potential for deployment of enhanced weathering (EW), via the application of crushed reactive silicate rocks (such as basalt), on over 680 million hectares of tropical agricultural and tree plantations to offset fossil fuel CO2 emissions. Warm tropical climates and productive crops will substantially enhance weathering rates, with potential co-benefits including decreased soil acidification and increased phosphorus supply promoting higher crop yields sparing forest for conservation, and reduced cultural eutrophication. Potential pitfalls include the impacts of mining operations on deforestation, producing the energy to crush and transport silicates and the erosion of silicates into rivers and coral reefs that increases inorganic turbidity, sedimentation and pH, with unknown impacts for biodiversity. We identify nine priority research areas for untapping the potential of EW in the tropics, including effectiveness of tropical agriculture at EW for major crops in relation to particle sizes and soil types, impacts on human health, and effects on farmland, adjacent forest and stream-water biodiversity. © 2017 The Author(s).

  9. Controls on coalbed methane potential and gas sorption characteristics of high-volatile bituminous coals in Indiana

    Science.gov (United States)

    Solano-Acosta, Wilfrido

    The increasing demand for energy and a growing concern for global warming, owing in part to the steep rise in anthropogenic greenhouse gas emissions, have sparked worldwide interest in clean coal technologies. Although the energy potential of coal is large, there are many environmental concerns associated with its large-scale utilization. An alternative solution to increasing demand for energy is the recovery of coalbed methane (CBM), an efficient and clean fossil fuel associated with extensive coal deposits. CBM today represents nearly 10 percent of the energy consumed in the United States. From an environmental perspective, coal beds that are too deep or that contain low-quality coal are being investigated as potential sites for permanently sequestering carbon dioxide emissions (CO2 sequestration). Methane has been documented in coals of various ranks. The occurrence and distribution of economically recoverable quantities of CBM result from the interplay between stratigraphy, tectonics, and hydrology. This study evaluates geologic factors that control the occurrence of CBM in Indiana coals, ranging from large-scale processes (i.e., burial and fracturing) to molecular interactions between CBM and the physical structure of coal (i.e., gas adsorption). This study investigates the role of tectonics and burial in the formation of coal fracture sets (cleats) that are critical for CBM extraction. Based on field data, I investigate the role of fracturing with regard to gas occurrence and CBM producibility. The timing of cleat formation is evaluated via carbon and oxygen isotopic signatures of cleat-filling minerals. In addition to field-scale observations, this study includes an experimental component that, based on a multitude of laboratory data, constrains optimum conditions for coal-sample preservation prior to laboratory analyses for exploration. Chemical analyses, petrography, grain-size distributions, Fourier transform infra-red (FTIR) spectroscopy, pore

  10. Manure management for greenhouse gas mitigation

    DEFF Research Database (Denmark)

    Petersen, Søren O; Blanchard, M.; Chadwick, D.

    2013-01-01

    are then presented, and potentials for positive and negative interactions between pollutants, and between management practices, are discussed. The diversity of manure properties and environmental conditions necessitate a modelling approach for improving estimates of GHG emissions, and for predicting effects...... of management changes for GHG mitigation, and requirements for such a model are discussed. Finally, we briefly discuss drivers for, and barriers against, introduction of GHG mitigation measures for livestock production. There is no conflict between efforts to improve food and feed production, and efforts......Ongoing intensification and specialisation of livestock production lead to increasing volumes of manure to be managed, which are a source of the greenhouse gases (GHGs) methane (CH4) and nitrous oxide (N2O). Net emissions of CH4 and N2O result from a multitude of microbial activities in the manure...

  11. THE POTENTIAL OF RECLAIMED LANDS TO SEQUESTER CARBON AND MITIGATE THE GREENHOUSE EFFECT

    Energy Technology Data Exchange (ETDEWEB)

    Terry Brown; Song Jin

    2006-05-01

    Reclaimed mine lands have the potential to sequester carbon. The use of amendments to increase fertility and overall soil quality is encouraging. Waste amendments such as sewage sludge and clarifier sludge, as well as commercial compost were tested to determine their effects on carbon sequestration and humic acid formation in reclaimed mine lands. Sewage sludge and clarifier sludge have the potential to work as reclaimed mine lands amendments. C:N ratios need to be understood to determine probability of nutrient leaching and water contamination. Microbial activity on the humic acid fraction of sludge is directed toward the readily degradable constituents containing single chain functional groups. This finding indicate that amendments with lower molecular constituents such as aliphatic compounds are more amenable to microbial degradation, therefore serves as better nutrient sources to enhance the formation of vegetation in mine lands and leads to more efficient carbon sequestration.

  12. Cleats and their relation to geologic lineaments and coalbed methane potential in Pennsylvanian coals in Indiana

    Energy Technology Data Exchange (ETDEWEB)

    Solano-Acosta, Wilfrido [Indiana Geological Survey, Indiana University, Bloomington, Indiana (United States); Department of Geological Sciences, Indiana University, Bloomington, Indiana (United States); Mastalerz, Maria [Indiana Geological Survey, Indiana University, Bloomington, Indiana (United States); Schimmelmann, Arndt [Department of Geological Sciences, Indiana University, Bloomington, Indiana (United States)

    2007-11-22

    Cleats and fractures in Pennsylvanian coals in southwestern Indiana were described, statistically analyzed, and subsequently interpreted in terms of their origin, relation to geologic lineaments, and significance for coal permeability and coalbed gas generation and storage. These cleats can be interpreted as the result of superimposed endogenic and exogenic processes. Endogenic processes are associated with coalification (i.e., matrix dehydration and shrinkage), while exogenic processes are mainly associated with larger-scale phenomena, such as tectonic stress. At least two distinct generations of cleats were identified on the basis of field reconnaissance and microscopic study: a first generation of cleats that developed early on during coalification and a second generation that cuts through the previous one at an angle that mimics the orientation of the present-day stress field. The observed parallelism between early-formed cleats and mapped lineaments suggests a well-established tectonic control during early cleat formation. Authigenic minerals filling early cleats represent the vestiges of once open hydrologic regimes. The second generation of cleats is characterized by less prominent features (i.e., smaller apertures) with a much less pronounced occurrence of authigenic mineralization. Our findings suggest a multistage development of cleats that resulted from tectonic stress regimes that changed orientation during coalification and basin evolution. The coals studied are characterized by a macrocleat distribution similar to that of well-developed coalbed methane basins (e.g., Black Warrior Basin, Alabama). Scatter plots and regression analyses of meso- and microcleats reveal a power-law distribution between spacing and cleat aperture. The same distribution was observed for fractures at microscopic scale. Our observations suggest that microcleats enhance permeability by providing additional paths for migration of gas out of the coal matrix, in addition to

  13. Drilling and Production Testing the Methane Hydrate Resource Potential Associated with the Barrow Gas Fields

    Energy Technology Data Exchange (ETDEWEB)

    Steve McRae; Thomas Walsh; Michael Dunn; Michael Cook

    2010-02-22

    In November of 2008, the Department of Energy (DOE) and the North Slope Borough (NSB) committed funding to develop a drilling plan to test the presence of hydrates in the producing formation of at least one of the Barrow Gas Fields, and to develop a production surveillance plan to monitor the behavior of hydrates as dissociation occurs. This drilling and surveillance plan was supported by earlier studies in Phase 1 of the project, including hydrate stability zone modeling, material balance modeling, and full-field history-matched reservoir simulation, all of which support the presence of methane hydrate in association with the Barrow Gas Fields. This Phase 2 of the project, conducted over the past twelve months focused on selecting an optimal location for a hydrate test well; design of a logistics, drilling, completion and testing plan; and estimating costs for the activities. As originally proposed, the project was anticipated to benefit from industry activity in northwest Alaska, with opportunities to share equipment, personnel, services and mobilization and demobilization costs with one of the then-active exploration operators. The activity level dropped off, and this benefit evaporated, although plans for drilling of development wells in the BGF's matured, offering significant synergies and cost savings over a remote stand-alone drilling project. An optimal well location was chosen at the East Barrow No.18 well pad, and a vertical pilot/monitoring well and horizontal production test/surveillance well were engineered for drilling from this location. Both wells were designed with Distributed Temperature Survey (DTS) apparatus for monitoring of the hydrate-free gas interface. Once project scope was developed, a procurement process was implemented to engage the necessary service and equipment providers, and finalize project cost estimates. Based on cost proposals from vendors, total project estimated cost is $17.88 million dollars, inclusive of design work

  14. Whole-farm models to quantify greenhouse gas emissions and their potential use for linking climate change mitigation and adaptation in temperate grassland ruminant-based farming systems.

    Science.gov (United States)

    Del Prado, A; Crosson, P; Olesen, J E; Rotz, C A

    2013-06-01

    The farm level is the most appropriate scale for evaluating options for mitigating greenhouse gas (GHG) emissions, because the farm represents the unit at which management decisions in livestock production are made. To date, a number of whole farm modelling approaches have been developed to quantify GHG emissions and explore climate change mitigation strategies for livestock systems. This paper analyses the limitations and strengths of the different existing approaches for modelling GHG mitigation by considering basic model structures, approaches for simulating GHG emissions from various farm components and the sensitivity of GHG outputs and mitigation measures to different approaches. Potential challenges for linking existing models with the simulation of impacts and adaptation measures under climate change are explored along with a brief discussion of the effects on other ecosystem services.

  15. Evaluating the potential of 'on-line' constructed wetlands for mitigating pesticide transfers from agricultural land to surface waters

    Science.gov (United States)

    Whelan, Michael; Ramos, Andre; Guymer, Ian; Villa, Raffaella; Jefferson, Bruce

    2016-04-01

    Pesticides make important contributions to modern agriculture but losses from land to water can present problems for environmental management, particularly in catchments where surface waters are abstracted for drinking water. Where artificial field drains represent a dominant pathway for pesticide transfers, buffer zones provide little mitigation potential. Instead, "on-line" constructed wetlands have been proposed as a potential means of reducing pesticide fluxes in drainage ditches and headwater streams. Here, we evaluate the potential of small free-surface wetlands to reduce pesticide concentrations in surface waters using a combination of field monitoring and numerical modelling. Two small constructed wetland systems in a first order catchment in Cambridgeshire, UK, were monitored over the 2014-2015 winter season. Discharge was measured at several flow control structures and samples were collected every eight hours and analysed for metaldehyde, a commonly-used molluscicide. Metaldehyde is moderately mobile and, like many other compounds, it has been regularly detected at high concentrations in surface water samples in a number of drinking water supply catchments in the UK over the past few years. However, it is unusually difficult to remove via conventional drinking water treatment which makes it particularly problematical for water companies. Metaldehyde losses from the upstream catchment were significant with peak concentrations occurring in the first storm events in early autumn, soon after application. Concentrations and loads appeared to be unaffected by transit through the wetland over a range of flow conditions - probably due to short solute residence times (quantified via several tracing experiments employing rhodamine WT - a fluorescent dye). A dynamic model, based on fugacity concepts, was constructed to describe chemical fate in the wetland system. The model was used to evaluate mitigation potential and management options under field conditions and

  16. Biofuel production and climate mitigation potential from marginal lands in US North Central region

    Science.gov (United States)

    Gelfand, I.; Sahajpal, R.; Zhang, X.; Izaurralde, R. C.; Robertson, G. P.

    2010-12-01

    An ever-increasing demand for liquid fuels, amidst concerns of anthropogenic impacts on the environment and fossil fuels availability, has spurred a strong interest in the development of agriculturally-based renewable energy sources. However, increasing demand for food as well as direct and indirect effects on land use, have raised concerns about reliance on grain-based ethanol and shifted research towards the direction of cellulosic feedstocks. In order to understand the future possibility for using agricultural systems for bio-fuel production, we present here a full greenhouse gas (GHG) balance of six potential sources of cellulosic feedstocks production. From 1991 to 2008, we measured GHGs sinks and sources in cropped and nearby unmanaged ecosystems in SW Michigan. The measurements included soil fluxes of GHGs (N2O and CH4), soil organic carbon concentration change, agronomic practices data, and biomass yields. We analyzed two types of intensively managed annual cropping systems under corn-soybean-wheat rotation (conventional tillage and no till), two perennial systems (alfalfa and poplar plantation), and one successional system. The use of agricultural residues for biofuel feedstock from conventionally-tilled crops had the lowest climate stabilization potential (-9 ±13 gCO2e m-2 y-1). In contrast, biomass collected from a successional system fertilized with N at123 kg ha-1y-1 showed the highest climate stabilization potential (-749 ±30 gCO2e m-2 y-1). We used our results to parameterize the EPIC model, which, together with GIS analysis was used to scale up the biomass productivity of the best environmentally performing systems to the marginal lands of the 10-state U.S. North Central region. Assuming 80 km as the maximum distance for road haulage to the biorefinery from the field, we identified 32 potential biorefinery placements each capable of supplying sufficient feedstock to produce at least 133 × 106 L y-1. In total, ethanol production from marginal

  17. Opportunities to reduce methane emissions in the natural gas industry

    Energy Technology Data Exchange (ETDEWEB)

    Cowgill, R.M. [Radian Corporation, Austin, TX (United States)

    1995-12-31

    The U.S. Environmental Protection Agency (EPA) and the Gas Research Institute (GRI) cofunded a project to quantify methane (CH{sub 4}) emissions from the U.S. natural gas industry. Methane, the major constituent of natural gas, is a potent greenhouse gas that is believed to increase the effect of global warming when released to the atmosphere. Reducing emissions from natural gas systems would lessen the greenhouse gas effect attributable to atmospheric CH{sub 4}. Further, mitigation methods to reduce emissions of natural gas, a marketable resource, could save money and increase energy efficiency. This presentation summarizes the major sources and quantity of methane being emitted to the atmosphere for all segments of the U.S. gas industry: production; processing; storage; transmission; and distribution. A description of how those emissions were determined is included here, as well as a discussion of which sources are potential candidates for reducing emissions. (author)

  18. Solar energy development and aquatic ecosystems in the southwestern United States: potential impacts, mitigation, and research needs.

    Science.gov (United States)

    Grippo, Mark; Hayse, John W; O'Connor, Ben L

    2015-01-01

    The cumulative impacts of utility-scale solar energy facilities on aquatic ecosystems in the Southwestern United States are of concern, considering the many existing regional anthropogenic stressors. We review the potential impacts of solar energy development on aquatic habitat and biota. The greatest potential for impacts is related to the loss, fragmentation, or prolonged drying of ephemeral water bodies and drainage networks resulting from the loss of desert washes within the construction footprint of the facility. Groundwater-dependent aquatic habitat may also be affected by operational groundwater withdrawal in the case of water-intensive solar technologies. Solar panels have also been found to attract aquatic insects and waterbirds, potentially resulting in mortality. Avoiding construction activity near perennial and intermittent surface waters is the primary means of reducing impacts on aquatic habitats, followed by measures to minimize erosion, sedimentation, and contaminant inputs into waterways. Currently, significant data gaps make solar facility impact assessment and mitigation more difficult. Examples include the need for more regional and site-specific studies of surface-groundwater connectivity, more detailed maps of regional stream networks and riparian vegetation corridors, as well as surveys of the aquatic communities inhabiting ephemeral streams. In addition, because they often lack regulatory protection, there is also a need to develop valuation criteria for ephemeral waters based on their ecological and hydrologic function within the landscape. By addressing these research needs, we can achieve the goal of greater reliance on solar energy, while at the same time minimizing impacts on desert ecosystems.

  19. Solar Energy Development and Aquatic Ecosystems in the Southwestern United States: Potential Impacts, Mitigation, and Research Needs

    Energy Technology Data Exchange (ETDEWEB)

    Grippo, Mark A.; Hayse, John; O' Connor, Ben L.

    2015-01-01

    The cumulative impacts of utility-scale solar energy facilities on aquatic ecosystems in the Southwestern United States are of concern, considering the many existing regional anthropogenic stressors. We review the potential impacts of solar energy development on aquatic habitat and biota. The greatest potential for impacts is related to the loss, fragmentation, or prolonged drying of ephemeral water bodies and drainage networks resulting from the loss of desert washes within the construction footprint of the facility. Groundwater-dependent aquatic habitat may also be affected by operational groundwater withdrawal in the case of water-intensive solar technologies. Solar panels have also been found to attract aquatic insects and waterbirds, potentially resulting in mortality. Avoiding construction activity near perennial and intermittent surface waters is the primary means of reducing impacts on aquatic habitats, followed by measures to minimize erosion, sedimentation, and contaminant inputs into waterways. Currently, significant data gaps make solar facility impact assessment and mitigation more difficult. Examples include the need for more regional and site-specific studies of surface–groundwater connectivity, more detailed maps of regional stream networks and riparian vegetation corridors, as well as surveys of the aquatic communities inhabiting ephemeral streams. In addition, because they often lack regulatory protection, there is also a need to develop valuation criteria for ephemeral waters based on their ecological and hydrologic function within the landscape. By addressing these research needs, we can achieve the goal of greater reliance on solar energy, while at the same time minimizing impacts on desert ecosystems.

  20. Evaluation of anaerobic co-digestion of dairy manure with food wastes via bio-methane potential assay and CSTR reactor.

    Science.gov (United States)

    Ye, Yulin; Zamalloa, Carlos; Lin, Hongjian; Yan, Mi; Schmidt, David; Hu, Bo

    2015-01-01

    The introduction of food wastes into anaerobic digestion (AD) brings a promising scenario of increasing feedstock availability and overall energy production from AD. This study evaluated the biodegradability and methane potential from co-digestion of two typical food wastes, kitchen waste and chicken fat, with dairy manure. For single substrate, the bio-methane potential assays showed that kitchen waste had the highest methane yield of 352 L-CH4 kg(-1)-VS added, 92% more than dairy manure alone. Chicken fat at the same Volatile Solid (VS) level (2 g L(-1)) inhibited bio-methane production. Addition of kitchen waste and chicken fat to a VS percentage of up to 40% improved overall methane yield by 44% and 34%, respectively. Synergistic effect was observed when either combining two or three substrates as AD feedstock, possibly as a result of increased biodegradability of organic materials in chicken fat and kitchen waste compared with dairy manure. Addition of chicken fat improved methane yield more than kitchen waste. However, addition of chicken fat VS over 0.8 g L(-1) should be cautiously done because it may cause reactor failure due to decrease in pH. The maximum methane yield was 425 L-CH4 kg(-1)-VS, achieved at a VS ratio of 2:2:1 for kitchen waste, chicken fat, and dairy manure. Results from batch AD experiment demonstrated that supplementing dairy manure to chicken fat and/or kitchen waste improved alkalinity of substrate due to the inclusion of more titratable bases in dairy manure, and therefore stabilized the methanogenesis and substantially improved biogas yield. A mixture of substrates of kitchen waste, chicken fat, and dairy manure at a ratio of 1:1:3 was fed to a continuously stirred tank reactor operated at organic loading rates of 3.28, 6.55, and 2.18 g-COD L(-1)-day (hydraulic retention time of 20, 10, and 30 days, respectively) under mesophilic condition, and methane production rate reached 0.65, 0.95, and 0.34 L-CH4 L(-1)-reactor-day.

  1. Potential of Svalbard reindeer winter droppings for emission/absorption of methane and nitrous oxide during summer

    Science.gov (United States)

    Hayashi, Kentaro; Cooper, Elisabeth J.; Loonen, Maarten J. J. E.; Kishimoto-Mo, Ayaka W.; Motohka, Takeshi; Uchida, Masaki; Nakatsubo, Takayuki

    2014-06-01

    Droppings of Svalbard reindeer (Rangifer tarandus platyrhynchus) could affect the carbon and nitrogen cycles in tundra ecosystems. The aim of this study was to evaluate the potential of reindeer droppings originating from the winter diet for emission and/or absorption of methane (CH4) and nitrous oxide (N2O) in summer. An incubation experiment was conducted over 14 days using reindeer droppings and mineral subsoil collected from a mound near Ny-Ålesund, Svalbard, to determine the potential exchanges of CH4 and N2O for combinations of two factors, reindeer droppings (presence or absence) and soil moisture (dry, moderate, or wet). A line transect survey was conducted to determine the distribution density of winter droppings at the study site. The incubation experiment showed a weak absorption of CH4 and a weak emission of N2O. Reindeer droppings originating from the winter diet had a negligible effect on the exchange fluxes of both CH4 and N2O. Although the presence of droppings resulted in a short-lasting increase in N2O emissions on day 1 (24 h from the start) for moderate and wet conditions, the emission rates were still very small, up to 3 μg N2O m-2 h-1.

  2. Cryoinsulation Material Development to Mitigate Obsolescence Risk for Global Warming Potential Foams

    Science.gov (United States)

    Protz, Alison; Bruyns, Roland; Nettles, Mindy

    2015-01-01

    Cryoinsulation foams currently being qualified for the Space Launch System (SLS) core stage are nonozone- depleting substances (ODP) and are compliant with current environmental regulations. However, these materials contain the blowing agent HFC-245fa, a hydrofluorocarbon (HFC), which is a Global Warming Potential (GWP) substance. In August 2014, the Environmental Protection Agency (EPA) proposed a policy change to reduce or eliminate certain HFCs, including HFC-245fa, in end-use categories including foam blowing agents beginning in 2017. The policy proposes a limited exception to allow continued use of HFC and HFC-blend foam blowing agents for military or space- and aeronautics-related applications, including rigid polyurethane spray foams, but only until 2022.

  3. Electrical potential-assisted DNA hybridization. How to mitigate electrostatics for surface DNA hybridization.

    Science.gov (United States)

    Tymoczko, Jakub; Schuhmann, Wolfgang; Gebala, Magdalena

    2014-12-24

    Surface-confined DNA hybridization reactions are sensitive to the number and identity of DNA capture probes and experimental conditions such as the nature and the ionic strength of the electrolyte solution. When the surface probe density is high or the concentration of bulk ions is much lower than the concentration of ions within the DNA layer, hybridization is significantly slowed down or does not proceed at all. However, high-density DNA monolayers are attractive for designing high-sensitivity DNA sensors. Thus, circumventing sluggish DNA hybridization on such interfaces allows a high surface concentration of target DNA and improved signal/noise ratio. We present potential-assisted hybridization as a strategy in which an external voltage is applied to the ssDNA-modified interface during the hybridization process. Results show that a significant enhancement of hybridization can be achieved using this approach.

  4. Phyto-remediation potential of Ipomoea aquatica for Cr(VI) mitigation.

    Science.gov (United States)

    Weerasinghe, Aruni; Ariyawnasa, Sanduni; Weerasooriya, Rohan

    2008-01-01

    Phyto-remedial efficiency of Ipomoea aquatica was examined at different experimental conditions for a period of 3 months. This plant was selected due to its easy establishment, tolerance and growing easiness. In all trials, the I. aquatica was grown in coir dust to ensure an inert medium. Essential growth nutrients were supplied externally using Albert solution. Once plant growth conditions were fixed, the model system was spiked with Cr(VI) solution in the range of 7-90 ppm. Up to 28 ppm Cr(VI), I. aquatica exhibits uniform absorption characteristics showing over 75% removal of added Cr(VI). At this stage I. aquatica was not affected and it showed no toxicity symptoms. Therefore, it is suited as a potential phyto-remediant. Further I. aquatica is a vegetable particularly in Asian region; therefore caution has to be taken when selecting it for human consumption due to its high chromium accumulation capacity.

  5. Biochemical methane potential of kraft bleaching effluent and codigestion with other in-mill streams

    DEFF Research Database (Denmark)

    Fitamo, Temesgen Mathewos; Dahl, Olli; Master, Emma;

    2016-01-01

    and in combination: total bleaching effluent, alkaline bleaching effluent, kraft evaporator condensate, and chemithermomechanical pulping effluent. The total bleaching effluent, consisting of the chlorine dioxide bleaching and alkaline bleaching effluents, exhibited the highest potential for organic matter...

  6. Biochemical methane potential of kraft bleaching effluent and codigestion with other in-mill streams

    DEFF Research Database (Denmark)

    Fitamo, Temesgen Mathewos; Dahl, Olli; Master, Emma

    2016-01-01

    and in combination: total bleaching effluent, alkaline bleaching effluent, kraft evaporator condensate, and chemithermomechanical pulping effluent. The total bleaching effluent, consisting of the chlorine dioxide bleaching and alkaline bleaching effluents, exhibited the highest potential for organic matter...

  7. Methane Potential and Enzymatic Saccharification of Steam-exploded Bagasse

    National Research Council Canada - National Science Library

    Vivekanand Vivekanand; Elisabeth F. Olsen; Vincent G.H. Eijsink; Svein Jarle Horn

    2014-01-01

    To evaluate the biofuel potential of bagasse, an abundant co-product in sugarcane-based industries, the effect of steam explosion on the efficiency of enzymatic saccharification and anaerobic digestion was studied...

  8. 控制灌溉稻田的甲烷减排效果%Mitigation of methane emissions from paddy fields under controlled irrigation

    Institute of Scientific and Technical Information of China (English)

    彭世彰; 和玉璞; 杨士红; 徐俊增; 侯会静

    2013-01-01

    In order to explore the influence of soil moisture regulation on methane (CH4) emissions under water-saving irrigation and look for an irrigation mode for rice that would save water while simultaneously limiting CH4 emissions, the regularity of CH4 emissions from paddy fields under controlled irrigation was analyzed based on 5 years’of field experiment data. Two different irrigation managements were conducted as follows with the same rice variety, cultivation practices and plant protection measures:controlled irrigation (CI) and irrigated intermittently flooded single aeration irrigation (FI). Rice was cultivated in a 150 m2 (20 m×7.5 m) plot between 2006 and 2007, each plot was separated by brick concrete with a height of 30 cm and width of 30 cm. Plastic anti-seepage films were inserted into soil plough layer to a depth of 50cm to isolate water exchange between the plots. For exploring the influence of rainfall on CH4 emissions from irrigated paddy fields and controlling soil moisture accurately, experiments were conducted in lysimeter with mobile canopy between 2009 and 2011, and each plot area was 5 m2(2.5 m×2 m). Gas samples were collected using manual static chamber and were analyzed by a gas chromatograph (ShimadzuGC-14B) with a flame ionization detector (FID) for CH4 concentration. The results showed that the total CH4 emissions from CI paddy fields were 1.07±0.17g/m2, which was significantly reduced by 83.5%compared with FI paddy fields (6.49±0.17 g/m2). Total seasonal and annual CH4 emissions from CI and FI paddy fields located in Southeast China were lower than the reported values. Meanwhile, the total annual CH4 emissions from controlled irrigation paddy fields was lower than that of paddy filed in most parts of the World. When compared to irrigated intermittently flooded multiple aeration, irrigated intermittently flooded single aeration and irrigated continuously flooded paddy fields, seasonal CH4 emissions from CI paddy fields decreased 94

  9. Enhanced CO2 uptake at a shallow Arctic Ocean seep field overwhelms the positive warming potential of emitted methane

    Science.gov (United States)

    Pohlman, John W.; Greinert, Jens; Ruppel, Carolyn; Silyakova, Anna; Vielstädte, Lisa; Casso, Michael; Mienert, Jürgen; Bünz, Stefan

    2017-05-01

    Continued warming of the Arctic Ocean in coming decades is projected to trigger the release of teragrams (1 Tg = 106 tons) of methane from thawing subsea permafrost on shallow continental shelves and dissociation of methane hydrate on upper continental slopes. On the shallow shelves (seep field on the Svalbard margin reveal atmospheric CO2 uptake rates (-33,300 ± 7,900 μmol m-2ṡd-1) twice that of surrounding waters and ˜1,900 times greater than the diffusive sea-air methane efflux (17.3 ± 4.8 μmol m-2ṡd-1). The negative radiative forcing expected from this CO2 uptake is up to 231 times greater than the positive radiative forcing from the methane emissions. Surface water characteristics (e.g., high dissolved oxygen, high pH, and enrichment of 13C in CO2) indicate that upwelling of cold, nutrient-rich water from near the seafloor accompanies methane emissions and stimulates CO2 consumption by photosynthesizing phytoplankton. These findings challenge the widely held perception that areas characterized by shallow-water methane seeps and/or strongly elevated sea-air methane flux always increase the global atmospheric greenhouse gas burden.

  10. Different methanotrophic potentials in stratified polar fjord waters (Storfjorden, Spitsbergen identified by using a combination of methane oxidation techniques

    Directory of Open Access Journals (Sweden)

    S. Mau

    2013-04-01

    Full Text Available The bacterially mediated aerobic methane oxidation (MOx is a key mechanism in controlling methane (CH4 emissions from the world's oceans to the atmosphere. In this study, we investigated MOx in the Arctic fjord Storfjorden (Spitsbergen by applying a combination of radio-tracer based incubation assays (3H-CH4 and 14H-CH4, stable C-CH4 isotope measurements, and molecular tools (16S rRNA DGGE-fingerprinting, pmoA- and mxaF gene analyses. Strofjorden is stratified in the summertime with melt water (MW in the upper 60 m of the water column, Arctic water (ArW between 60–100 m and brine-enriched shelf water (BSW down to 140 m. CH4 concentrations were supersaturated with respect to the atmospheric equilibrium (∼3 nM throughout the water column, increasing from ∼20 nM at the surface to a maximum of 72 nM at 60 m and decreasing below. MOx rate measurements at near in situ CH4 concentrations (here measured with 3H-CH4 raising the ambient CH4 pool by −1 at 60 m followed by a decrease in the deeper ArW/BSW. In contrast, rate measurements with 14H-CH4 at elevated CH4 concentrations (incubations were spiked with ∼450 nM of 14H-CH4, providing an estimate of the CH4 oxidation potential showed comparably low turnover rates (−1 at 60 m, but peaked in ArW/BSW at ∼100 m water depth, concomitant with increasing 14C-values in the residual CH4 pool. Our results indicate that the MOx community in the surface MW is adapted to relatively low CH4 concentrations. In contrast, the activity of the deep water MOx community is relatively low at the ambient, summertime CH4 concentrations but has the potential to increase rapidly in response to CH4 availability. A similar distinction between surface and deep water MOx is also suggested by our molecular analyses. Although, we found pmoA and maxF gene sequences throughout the water column attesting the ubiquitous presence of MOx communities in Storfjorden, deep water amplicons of pmoA and maxF were unusually long

  11. Nitrification Inhibitors: A Perspective Tool to Mitigate Greenhouse Gas Emissions from Rice Soils

    Directory of Open Access Journals (Sweden)

    Sandeep K. Malyan

    2016-08-01

    Full Text Available Rice fields are significant contributors of greenhouse gases mainly methane and nitrous oxide to the atmosphere. Increasing concentrations of these greenhouse gases play significant role in changing atmospheric chemistry such as mean air temperature, rainfall pattern, drought, and flood frequency. Mitigation of greenhouse gases for achieving sustainable agriculture without affecting economical production is one the biggest challenge of twenty first century at national and global scale. On the basis of published scientific studies, we hereby assess the use of nitrification inhibitors for greenhouse gas mitigation from rice soil. Biologically oxidation of ammonium to nitrate is termed as nitrification and materials which suppress this process are known as nitrification inhibitors. Soil amendment by addition of certain nitrification inhibitors such as neem oil coated urea, nimin-coated urea; dicyandiamide, encapsulated calcium carbide, and hydroquinone reduce cumulative methane and nitrous oxide emission from rice. Firstly, these inhibitors reduce nitrous oxide emissions both directly by nitrification (by reducing NH4+ to NO3- as well as indirectly by de-nitrification (by reducing NO3- availability in soil. Secondly, methane emission from rice soil can be reduced by enhancing methane oxidation and suppressing methane production and further by reducing the aerenchymal transportation through rice plant. Application of some of the nitrification inhibitors such as calcium carbide and encapsulated calcium carbide reduce methane production by releasing acetylene gas which helps in reducing the population of methanogenic microbes in the soil. Application of nitrification inhibitors also helps to maintain soil redox potential at higher level subsequently reducing cumulative methane emission from soil. Plant derived organic nitrification inhibitors (neem oil, neem cake, karanja seed extract are eco-friendly and possess substantial greenhouse gas mitigation

  12. Potential of barrage fish ponds for the mitigation of pesticide pollution in streams.

    Science.gov (United States)

    Gaillard, Juliette; Thomas, Marielle; Lazartigues, Angélique; Bonnefille, Bénilde; Pallez, Christelle; Dauchy, Xavier; Feidt, Cyril; Banas, Damien

    2016-01-01

    Barrage fishponds may represent a significant surface water area in some French regions. Knowledge on their effect on water resources is therefore necessary for the development of appropriate water quality management plans at the regional scale. Although there is much information on the nutrient removal capacity of these water bodies, little attention has been paid to other agricultural contaminants such as pesticides. The present paper reports the results of a 1-year field monitoring of pesticide concentrations and water flows measured upstream and downstream from a fishpond in North East France to evaluate its capacity in reducing pesticide loads. Among the 42 active substances that had been applied on the fishpond's catchment, seven pesticides (five herbicides, two fungicides) were studied. The highest concentration in the inflow to the pond was 26.5 μg/L (MCPA), while the highest concentration in pond outflow was 0.54 μg/L (prosulfocarb). Removal rates of dissolved pesticides in the fishpond ranged from 0-8% (prosulfocarb) to 100% (clopyralid). Although not primarily designed for the treatment of diffuse sources of pesticides, the studied fishpond had the potential to do so.

  13. Renewable energy development in China: Resource assessment, technology status, and greenhouse gas mitigation potential

    Energy Technology Data Exchange (ETDEWEB)

    Wan, Y.; Renne, O.D. [National Renewable Energy Lab., Golden, CO (United States); Junfeng, Li [Energy Research Institute, Beijing (China)

    1996-12-31

    China, which has pursued aggressive policies to encourage economic development, could experience the world`s fastest growth in energy consumption over the next two decades. China has become the third largest energy user in the world since 1990 when primary energy consumption reached 960 million tons of coal equivalent (tce). Energy use is increasing at an annual rate of 6-7% despite severe infrastructure and capital constraints on energy sector development. Energy consumption in China is heavily dominated by coal, and fossil fuels provide up to 95% of all commercial energy use. Coal currently accounts for 77% of total primary energy use; oil, 16%; hydropower, 5%; and natural gas, 2%. Coal is expected to continue providing close to three-quarters of all energy consumed, and the amount of coal used is expected to triple by year 2020. Currently, renewable energy resources (except for hydropower) account for only a fraction of total energy consumption. However, the estimated growth in greenhouse gas emissions, as well as serious local and regional environmental pollution problems caused by combustion of fossil fuels, provides strong arguments for the development of renewable energy resources. Renewable energy potential in China is significantly greater than that indicated by the current level of use. With a clear policy goal and consistent efforts from the Government of China, renewables can play a far larger role in its future energy supply.

  14. Peaking China’s CO2 Emissions: Trends to 2030 and Mitigation Potential

    Directory of Open Access Journals (Sweden)

    Qiang Liu

    2017-02-01

    Full Text Available China has submitted its nationally determined contribution to peak its energy-related emissions around 2030. To understand how China might develop its economy while controlling CO2 emissions, this study surveys a number of recent modeling scenarios that project the country’s economic growth, energy mix, and associated emissions until 2050. Our analysis suggests that China’s CO2 emissions will continue to grow until 2040 or 2050 and will approximately double their 2010 level without additional policy intervention. The alternative scenario, however, suggests that peaking CO2 emissions around 2030 requires the emission growth rate to be reduced by 2% below the reference level. This step would result in a plateau in China’s emissions from 2020 to 2030. This paper also proposed a deep de-carbonization pathway for China that is consistent with China’s goal of peaking emissions by around 2030, which can best be achieved through a combination of improvements in energy and carbon intensities. Our analysis also indicated that the potential for energy intensity decline will be limited over time. Thus, the peaking will be largely dependent on the share of non-fossil fuel energy in primary energy consumption.

  15. Influence of the set anode potential on the performance and internal energy losses of a methane-producing microbial electrolysis cell.

    Science.gov (United States)

    Villano, Marianna; Ralo, Cláudia; Zeppilli, Marco; Aulenta, Federico; Majone, Mauro

    2016-02-01

    The effect of the set anode potential (between + 200 mV and - 200 mV vs. SHE, standard hydrogen electrode) on the performance and distribution of internal potential losses has been analyzed in a continuous-flow methane-producing microbial electrolysis cell (MEC).Both acetate removal rate (at the anode) and methane generation rate (at the cathode) were higher (1 gCOD/L day and 0.30 m(3)/m(3) day, respectively) when the anode potential was controlled at + 200 mV. However, both the yields of acetate conversion into current and current conversion into methane were very high (72-90%) under all the tested conditions. Moreover, the sum of internal potential losses decreased from 1.46 V to 0.69 V as the anode potential was decreased from + 200 mV to - 200 mV, with cathode overpotentials always representing the main potential losses. This was likely to be due to the high energy barrier which has to be overcome in order to activate the cathode reaction. Finally, the energy efficiency correspondingly increased reaching 120% when the anode was controlled at - 200 mV.

  16. Reforestation in a high-CO2 world -- Higher mitigation potential than expected, lower adaptation potential than hoped for

    Science.gov (United States)

    Sonntag, Sebastian; Pongratz, Julia; Reick, Christian H.; Schmidt, Hauke

    2016-06-01

    We assess the potential and possible consequences for the global climate of a strong reforestation scenario for this century. We perform model experiments using the Max Planck Institute Earth System Model (MPI-ESM), forced by fossil-fuel CO2 emissions according to the high-emission scenario Representative Concentration Pathway (RCP) 8.5, but using land use transitions according to RCP4.5, which assumes strong reforestation. Thereby, we isolate the land use change effects of the RCPs from those of other anthropogenic forcings. We find that by 2100 atmospheric CO2 is reduced by 85 ppm in the reforestation model experiment compared to the reference RCP8.5 model experiment. This reduction is higher than previous estimates and is due to increased forest cover in combination with climate and CO2 feedbacks. We find that reforestation leads to global annual mean temperatures being lower by 0.27 K in 2100. We find large annual mean warming reductions in sparsely populated areas, whereas reductions in temperature extremes are also large in densely populated areas.

  17. Impact of non-petroleum vehicle fuel economy on GHG mitigation potential

    Science.gov (United States)

    Luk, Jason M.; Saville, Bradley A.; MacLean, Heather L.

    2016-04-01

    The fuel economy of gasoline vehicles will increase to meet 2025 corporate average fuel economy standards (CAFE). However, dedicated compressed natural gas (CNG) and battery electric vehicles (BEV) already exceed future CAFE fuel economy targets because only 15% of non-petroleum energy use is accounted for when determining compliance. This study aims to inform stakeholders about the potential impact of CAFE on life cycle greenhouse gas (GHG) emissions, should non-petroleum fuel vehicles displace increasingly fuel efficient petroleum vehicles. The well-to-wheel GHG emissions of a set of hypothetical model year 2025 light-duty vehicles are estimated. A reference gasoline vehicle is designed to meet the 2025 fuel economy target within CAFE, and is compared to a set of dedicated CNG vehicles and BEVs with different fuel economy ratings, but all vehicles meet or exceed the fuel economy target due to the policy’s dedicated non-petroleum fuel vehicle incentives. Ownership costs and BEV driving ranges are estimated to provide context, as these can influence automaker and consumer decisions. The results show that CNG vehicles that have lower ownership costs than gasoline vehicles and BEVs with long distance driving ranges can exceed the 2025 CAFE fuel economy target. However, this could lead to lower efficiency CNG vehicles and heavier BEVs that have higher well-to-wheel GHG emissions than gasoline vehicles on a per km basis, even if the non-petroleum energy source is less carbon intensive on an energy equivalent basis. These changes could influence the effectiveness of low carbon fuel standards and are not precluded by the light-duty vehicle GHG emissions standards, which regulate tailpipe but not fuel production emissions.

  18. Greenhouse gases mitigation potential and costs for Brazil's energy system from 2010 to 2030

    Energy Technology Data Exchange (ETDEWEB)

    Borba, Bruno S.M.C.; Lucena, Andre F.P. de; Rathmann, Regis; Costa, Isabella V.L. da; Nogueira, Larissa P.P.; Rochedo, Pedro R.R.; H. Junior, Mauricio F.; Szklo, Alexandre; Schaeffer, Roberto [Coordenacao dos Programas de Pos-Graduacao de Engenharia (PPE/COPPE/UFRJ), RJ (Brazil). Programa de Planejamento Energetico

    2012-07-01

    This paper analyses the potential for energy-related greenhouse gas (GHG) emission reductions and their abatement costs in the energy system of Brazil. The analysis of mitigation options and their costs focuses on the following sectors: industry, transportation and energy supply (electricity generation and oil refining), given their large contribution to the Brazil's GHGs emissions. For the industrial and oil refining sectors, the paper estimated abatement costs based on the investments along with the energy and operational costs of the measures considered. Two discount rates were used: 15% a year (private discount rate) and 8% a year (social discount rate). Compared to a business-as-usual reference scenario, results show a potential to reduce future energy-related GHG emissions by 27% in 2030. This study shows, however, that in relation to a reference year (2007), the examined abatement measures, along with the socioeconomic dynamics of an emerging country such as Brazil, would not be enough to attain absolute reductions in GHG emissions by 2030. This result is valid both each sector individually and for the sum of the emissions from all the sectors analyzed. (author)

  19. Melatonin mitigates cadmium phytotoxicity through modulation of phytochelatins biosynthesis, vacuolar sequestration and antioxidant potential in Solanum lycopersicum L.

    Directory of Open Access Journals (Sweden)

    Jie eZhou

    2015-08-01

    Full Text Available Melatonin is a ubiquitous signal molecule, playing crucial roles in plant growth and stress tolerance. Recently, toxic metal cadmium (Cd has been reported to regulate melatonin content in rice; however, the function of melatonin under Cd stress, particularly in higher plants, still remains elusive. Here, we show that optimal dose of melatonin could effectively ameliorate Cd-induced phytotoxicity in tomato. The contents of Cd and melatonin were gradually increased over time under Cd stress. However, such increase in endogenous melatonin was incapable to reverse detrimental effects of Cd. Meanwhile, supplementation with melatonin conferred Cd tolerance as evident by plant biomass and photosynthesis. In addition to notable increase in antioxidant enzymes activity, melatonin-induced Cd stress mitigation was closely associated with enhanced H+-ATPase activity and the contents of glutathione and phytochelatins. Although exogenous melatonin had no effect on root Cd content, it significantly reduced leaf Cd content, indicating its role in Cd transport. Analysis of Cd in different subcellular compartments revealed that melatonin increased cell wall and vacuolar fractions of Cd. Our results suggest that melatonin-induced enhancements in antioxidant potential, phytochelatins biosynthesis and subsequent Cd sequestration might play a critical role in plant tolerance to Cd. Such a mechanism may have potential implication in safe food production.

  20. Melatonin mitigates cadmium phytotoxicity through modulation of phytochelatins biosynthesis, vacuolar sequestration, and antioxidant potential in Solanum lycopersicum L.

    Science.gov (United States)

    Hasan, Md Kamrul; Ahammed, Golam Jalal; Yin, Lingling; Shi, Kai; Xia, Xiaojian; Zhou, Yanhong; Yu, Jingquan; Zhou, Jie

    2015-01-01

    Melatonin is a ubiquitous signal molecule, playing crucial roles in plant growth and stress tolerance. Recently, toxic metal cadmium (Cd) has been reported to regulate melatonin content in rice; however, the function of melatonin under Cd stress, particularly in higher plants, still remains elusive. Here, we show that optimal dose of melatonin could effectively ameliorate Cd-induced phytotoxicity in tomato. The contents of Cd and melatonin were gradually increased over time under Cd stress. However, such increase in endogenous melatonin was incapable to reverse detrimental effects of Cd. Meanwhile, supplementation with melatonin conferred Cd tolerance as evident by plant biomass and photosynthesis. In addition to notable increase in antioxidant enzymes activity, melatonin-induced Cd stress mitigation was closely associated with enhanced H(+)-ATPase activity and the contents of glutathione and phytochelatins. Although exogenous melatonin had no effect on root Cd content, it significantly reduced leaf Cd content, indicating its role in Cd transport. Analysis of Cd in different subcellular compartments revealed that melatonin increased cell wall and vacuolar fractions of Cd. Our results suggest that melatonin-induced enhancements in antioxidant potential, phytochelatins biosynthesis and subsequent Cd sequestration might play a critical role in plant tolerance to Cd. Such a mechanism may have potential implication in safe food production.

  1. Methane Flux

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Methane (CH4) flux is the net rate of methane exchange between an ecosystem and the atmosphere. Data of this variable were generated by the USGS LandCarbon project...

  2. Contribution of anaerobic digesters to emissions mitigation and electricity generation under U.S. climate policy.

    Science.gov (United States)

    Zaks, David P M; Winchester, Niven; Kucharik, Christopher J; Barford, Carol C; Paltsev, Sergey; Reilly, John M

    2011-08-15

    Livestock husbandry in the U.S. significantly contributes to many environmental problems, including the release of methane, a potent greenhouse gas (GHG). Anaerobic digesters (ADs) break down organic wastes using bacteria that produce methane, which can be collected and combusted to generate electricity. ADs also reduce odors and pathogens that are common with manure storage and the digested manure can be used as a fertilizer. There are relatively few ADs in the U.S., mainly due to their high capital costs. We use the MIT Emissions Prediction and Policy Analysis (EPPA) model to test the effects of a representative U.S. climate stabilization policy on the adoption of ADs which sell electricity and generate methane mitigation credits. Under such policy, ADs become competitive at producing electricity in 2025, when they receive methane reduction credits and electricity from fossil fuels becomes more expensive. We find that ADs have the potential to generate 5.5% of U.S. electricity.

  3. The influence of redox potential on the degradation of halogenated methanes

    NARCIS (Netherlands)

    Olivas, Y.; Dolfing, J.; Smith, G.B.

    2002-01-01

    To determine the influence of redox potential on the reaction mechanism and to quantify kinetics of the dechlorination by digester sludge, the test compounds trichlorofluoromethane (CFCl3), carbon tetrachloride (CCl4), and chloroform (CHCl3) were incubated in the presence of sludge and variable conc

  4. Utilization of coalbed methane

    Energy Technology Data Exchange (ETDEWEB)

    Gustavson, J.B. [Gustavson Associates Inc., Boulder, CO (United States)

    1996-02-01

    Substantial progress has been made in capturing coalbed methane (CBM gas), which constitutes a valuable source of clean burning energy. It is of importance to study the various potential uses of coalbed methane and to understand the various technologies required, as well as their economics and any institutional constraints. In industrialised countries, the uses of coalbed methane are almost solely dependent on microeconomics; coalbed methane must compete for a market against natural gas and other energy sources - and frequently, coalbed methane is not competitive against other energy sources. In developing countries, on the other hand, particularly where other sources of energy are in short supply, coalbed methane economics yield positive results. Here, constraints to development of CBM utilization are mainly lack of technology and investment capital. Sociological aspects such as attitude and cultural habits, may also have a strong negative influence. This paper outlines the economics of coalbed methane utilization, particularly its competition with natural gas, and touches upon the many different uses to which coalbed methane may be applied. 24 refs., 4 figs.

  5. Methane, carbon dioxide and nitrous oxide fluxes from a temperate salt marsh: Grazing management does not alter Global Warming Potential

    Science.gov (United States)

    Ford, Hilary; Garbutt, Angus; Jones, Laurence; Jones, Davey L.

    2012-11-01

    Soil greenhouse gas emissions from cattle grazed and un-grazed temperate upper salt marsh were measured using dark static chambers, monthly for one year. Below-ground gas sampling tubes were also used to measure soil methane (CH4) concentrations. CH4 efflux from grazed and un-grazed salt marsh did not differ significantly although grazing did lead to 'hotspots' of underground CH4 (up to 6% of total air volume) and CH4 efflux (peak of 9 mg m-2 h-1) significantly linked to high soil moisture content, low soil temperatures and the presence of Juncus gerardii. Carbon dioxide (CO2) efflux was greater from the un-grazed marsh (mean of 420 mg m-2 h-1) than the grazed marsh (mean of 333 mg m-2 h-1) throughout most of the year and was positively correlated with the deeper water table and greater soil temperatures. Grazing was not a significant predictor of nitrous oxide (N2O) soil emissions. Global Warming Potential (GWP; over 100 years), calculated from mean yearly chamber fluxes for CH4 and CO2, did not differ significantly with grazing treatment. Seasonal variation in the key drivers of soil greenhouse gas efflux; soil temperature, moisture and water table, plus the presence or absence of aerenchymatous plants such as J. gerardii were more important to the magnitude of greenhouse gas emissions than grazing management per se.

  6. Influence of rumen protozoa on methane emission in ruminants: a meta-analysis approach.

    Science.gov (United States)

    Guyader, J; Eugène, M; Nozière, P; Morgavi, D P; Doreau, M; Martin, C

    2014-11-01

    A meta-analysis was conducted to evaluate the effects of protozoa concentration on methane emission from ruminants. A database was built from 59 publications reporting data from 76 in vivo experiments. The experiments included in the database recorded methane production and rumen protozoa concentration measured on the same groups of animals. Quantitative data such as diet chemical composition, rumen fermentation and microbial parameters, and qualitative information such as methane mitigation strategies were also collected. In the database, 31% of the experiments reported a concomitant reduction of both protozoa concentration and methane emission (g/kg dry matter intake). Nearly all of these experiments tested lipids as methane mitigation strategies. By contrast, 21% of the experiments reported a variation in methane emission without changes in protozoa numbers, indicating that methanogenesis is also regulated by other mechanisms not involving protozoa. Experiments that used chemical compounds as an antimethanogenic treatment belonged to this group. The relationship between methane emission and protozoa concentration was studied with a variance-covariance model, with experiment as a fixed effect. The experiments included in the analysis had a within-experiment variation of protozoa concentration higher than 5.3 log10 cells/ml corresponding to the average s.e.m. of the database for this variable. To detect potential interfering factors for the relationship, the influence of several qualitative and quantitative secondary factors was tested. This meta-analysis showed a significant linear relationship between methane emission and protozoa concentration: methane (g/kg dry matter intake)=-30.7+8.14×protozoa (log10 cells/ml) with 28 experiments (91 treatments), residual mean square error=1.94 and adjusted R 2=0.90. The proportion of butyrate in the rumen positively influenced the least square means of this relationship.

  7. Mitigation of Humic Acid Inhibition in Anaerobic Digestion of Cellulose by Addition of Various Salts

    Directory of Open Access Journals (Sweden)

    Samet Azman

    2015-03-01

    Full Text Available Humic compounds are inhibitory to the anaerobic hydrolysis of cellulosic biomass. In this study, the impact of salt addition to mitigate the inhibitory effects of humic compounds was investigated. The experiment was conducted using batch tests to monitor the anaerobic hydrolysis of cellulose in the presence of humic acid. Sodium, potassium, calcium, magnesium and iron salts were tested separately for their efficiency to mitigate humic acid inhibition. All experiments were done under mesophilic conditions (30 °C and at pH 7. Methane production was monitored online, using the Automatic Methane Potential Test System. Methane production, soluble chemical oxygen demand and volatile fatty acid content of the samples were measured to calculate the hydrolysis efficiencies. Addition of magnesium, calcium and iron salts clearly mitigated the inhibitory effects of humic acid and hydrolysis efficiencies reached up to 75%, 65% and 72%, respectively, which were similar to control experiments. Conversely, potassium and sodium salts addition did not mitigate the inhibition and hydrolysis efficiencies were found to be less than 40%. Mitigation of humic acid inhibition via salt addition was also validated by inductively coupled plasma atomic emission spectroscopy analyses, which showed the binding capacity of different cations to humic acid.

  8. Optimization of co-digestion of various industrial sludges for biogas production and sludge treatment: methane production potential experiments and modeling.

    Science.gov (United States)

    Mahanty, Biswanath; Zafar, Mohd; Han, Man Jae; Park, Hung-Suck

    2014-06-01

    Optimal biogas production and sludge treatment were studied by co-digestion experiments and modeling using five different wastewater sludges generated from paper, chemical, petrochemical, automobile, and food processing industries situated in Ulsan Industrial Complex, Ulsan, South Korea. The biomethane production potential test was conducted in simplex-centroid mixture design, fitted to regression equation, and some optimal co-digestion scenarios were given by combined desirability function based multi-objective optimization technique for both methane yield and the quantity of sludge digested. The co-digestion model incorporating main and interaction effects among sludges were utilized to predict the maximum possible methane yield. The optimization routine for methane production with different industrial sludges in batches were repeated with the left-over sludge of earlier cycle, till all sludges have been completely treated. Among the possible scenarios, a maximum methane yield of 1161.53 m(3) is anticipated in three batches followed by 1130.33 m(3) and 1045.65 m(3) in five and two batches, respectively. This study shows a scientific approach to find a practical solution to utilize diverse industrial sludges in both treatment and biogas production perspectives.

  9. The growing role of methane in anthropogenic climate change

    Science.gov (United States)

    Saunois, M.; Jackson, R. B.; Bousquet, P.; Poulter, B.; Canadell, J. G.

    2016-12-01

    Unlike CO2, atmospheric methane concentrations are rising faster than at any time in the past two decades and, since 2014, are now approaching the most greenhouse-gas-intensive scenarios. The reasons for this renewed growth are still unclear, primarily because of uncertainties in the global methane budget. New analysis suggests that the recent rapid rise in global methane concentrations is predominantly biogenic-most likely from agriculture-with smaller contributions from fossil fuel use and possibly wetlands. Additional attention is urgently needed to quantify and reduce methane emissions. Methane mitigation offers rapid climate benefits and economic, health and agricultural co-benefits that are highly complementary to CO2 mitigation.

  10. Quantifying Fugitive Methane Emissions at an Underground Coal Fire Using Cavity Ring-Down Spectroscopy Technology

    Science.gov (United States)

    Fleck, D.; Gannon, L.; Kim-Hak, D.; Ide, T.

    2016-12-01

    Understanding methane emissions is of utmost importance due to its greenhouse warming potential. Methane emissions can occur from a variety of natural and anthropogenic sources which include wetlands, landfills, oil/gas/coal extraction activities, underground coal fires, and natural gas distribution systems. Locating and containing these emissions are critical to minimizing their environmental impacts and economically beneficial when retrieving large fugitive amounts. In order to design a way to mitigate these methane emissions, they must first be accurately quantified. One such quantification method is to measure methane fluxes, which is a measurement technique that is calculated based on rate of gas accumulation in a known chamber volume over methane seepages. This allows for quantification of greenhouse gas emissions at a localized level (sub one meter) that can complement remote sensing and other largescale modeling techniques to further paint the picture of emission points. High performance analyzers are required to provide both sufficient temporal resolution and precise concentration measurements in order to make these measurements over only minutes. A method of measuring methane fluxes was developed using the latest portable, battery-powered Cavity Ring-Down Spectroscopy analyzer from Picarro (G4301). In combination with a mobile accumulation chamber, the instrument allows for rapid measurement of methane and carbon dioxide fluxes over wide areas. For this study, methane fluxes that were measured at an underground coal fire near the Four Corners region using the Picarro analyzer are presented. The flux rates collected demonstrate the ability for the analyzer to detect methane fluxes across many orders of magnitude. Measurements were accompanied by simultaneously geotagging the measurements with GPS to georeferenced the data. Methane flux data were instrumental in our ability to characterize the extent and the migration of the underground fire. In the future

  11. Endophytes from medicinal plants and their potential for producing indole acetic acid, improving seed germination and mitigating oxidative stress* #

    Science.gov (United States)

    Khan, Abdul Latif; Gilani, Syed Abdullah; Waqas, Muhammad; Al-Hosni, Khadija; Al-Khiziri, Salima; Kim, Yoon-Ha; Ali, Liaqat; Kang, Sang-Mo; Asaf, Sajjad; Shahzad, Raheem; Hussain, Javid; Lee, In-Jung; Al-Harrasi, Ahmed

    2017-01-01

    Medicinal plants have been used by marginal communities to treat various ailments. However, the potential of endophytes within these bio-prospective medicinal plants remains unknown. The present study elucidates the endophytic diversity of medicinal plants (Caralluma acutangula, Rhazya stricta, and Moringa peregrina) and the endophyte role in seed growth and oxidative stress. Various organs of medicinal plants yielded ten endophytes, which were identified as Phoma sp. (6 isolates), Alternaria sp. (2), Bipolaris sp. (1), and Cladosporium sp. (1) based on 18S rDNA sequencing and phylogenetic analysis. The culture filtrates (CFs; 25%, 50%, and 100% concentrations) from these endophytes were tested against the growth of normal and dwarf mutant rice lines. Endophytic CF exhibited dose-dependent growth stimulation and suppression effects. CF (100%) of Phoma sp. significantly increased rice seed germination and growth compared to controls and other endophytes. This growth-promoting effect was due to the presence of indole acetic acid in endophytic CF. The gas chromatography/mass spectrometry (GC/MS) analysis showed the highest indole acetic acid content ((54.31±0.21) µmol/L) in Bipolaris sp. In addition, the isolate of Bipolaris sp. exhibited significantly higher radical scavenging and anti-lipid peroxidation activity than the other isolates. Bipolaris sp. and Phoma sp. also exhibited significantly higher flavonoid and phenolic contents. The medicinal plants exhibited the presence of bio-prospective endophytic strains, which could be used for the improvement of crop growth and the mitigation of oxidative stresses. PMID:28124841

  12. An Analysis of the Climate Change Mitigation Potential through Soil Organic Carbon Sequestration in a Corn Belt Watershed.

    Science.gov (United States)

    Bhattarai, Mukesh Dev; Secchi, Silvia; Schoof, Justin

    2017-01-01

    Land-based carbon sequestration constitutes a major low cost and immediately viable option in climate change mitigation. Using downscaled data from eight atmosphere-ocean general circulation models for a simulation period between 2015 and 2099, we examine the carbon sequestration potential of alternative agricultural land uses in an intensively farmed Corn Belt watershed and the impact of climate change on crop yields. Our results show that switching from conventional tillage continuous corn to no-till corn-soybean can sequester the equivalent of 192.1 MtCO2 eq of soil organic carbon per hectare with a sequestration rate of 2.26 MtCO2 eq ha(-1) yr(-1). Our results also indicate that switchgrass can sequester the equivalent of 310.7 MtCO2 eq of soil organic carbon per hectare with a sequestration rate of 3.65 MtCO2 eq ha(-1) yr(-1). Our findings suggest that, unlike for corn and soybean yields, climate change does not have a significant effect on switchgrass yields, possibly due to the carbon fertilization effect.

  13. An Analysis of the Climate Change Mitigation Potential through Soil Organic Carbon Sequestration in a Corn Belt Watershed

    Science.gov (United States)

    Bhattarai, Mukesh Dev; Secchi, Silvia; Schoof, Justin

    2017-01-01

    Land-based carbon sequestration constitutes a major low cost and immediately viable option in climate change mitigation. Using downscaled data from eight atmosphere-ocean general circulation models for a simulation period between 2015 and 2099, we examine the carbon sequestration potential of alternative agricultural land uses in an intensively farmed Corn Belt watershed and the impact of climate change on crop yields. Our results show that switching from conventional tillage continuous corn to no-till corn-soybean can sequester the equivalent of 192.1 MtCO2 eq of soil organic carbon per hectare with a sequestration rate of 2.26 MtCO2 eq ha-1 yr-1. Our results also indicate that switchgrass can sequester the equivalent of 310.7 MtCO2 eq of soil organic carbon per hectare with a sequestration rate of 3.65 MtCO2 eq ha-1 yr-1. Our findings suggest that, unlike for corn and soybean yields, climate change does not have a significant effect on switchgrass yields, possibly due to the carbon fertilization effect.

  14. Identifying and Mitigating Potential Nutrient and Sediment Hot Spots under a Future Scenario in the Missouri River Basin

    Energy Technology Data Exchange (ETDEWEB)

    Wu, May [Argonne National Lab. (ANL), Argonne, IL (United States); Zhang, Zhonglong [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-09-01

    Using the Soil and Water Assessment Tool (SWAT) for large-scale watershed modeling could be useful for evaluating the quality of the water in regions that are dominated by nonpoint sources in order to identify potential “hot spots” for which mitigating strategies could be further developed. An analysis of water quality under future scenarios in which changes in land use would be made to accommodate increased biofuel production was developed for the Missouri River Basin (MoRB) based on a SWAT model application. The analysis covered major agricultural crops and biofuel feedstock in the MoRB, including pasture land, hay, corn, soybeans, wheat, and switchgrass. The analysis examined, at multiple temporal and spatial scales, how nitrate, organic nitrogen, and total nitrogen; phosphorus, organic phosphorus, inorganic phosphorus, and total phosphorus; suspended sediments; and water flow (water yield) would respond to the shifts in land use that would occur under proposed future scenarios. The analysis was conducted at three geospatial scales: (1) large tributary basin scale (two: Upper MoRB and Lower MoRB); (2) regional watershed scale (seven: Upper Missouri River, Middle Missouri River, Middle Lower Missouri River, Lower Missouri River, Yellowstone River, Platte River, and Kansas River); and (3) eight-digit hydrologic unit (HUC-8) subbasin scale (307 subbasins). Results showed that subbasin-level variations were substantial. Nitrogen loadings decreased across the entire Upper MoRB, and they increased in several subbasins in the Lower MoRB. Most nitrate reductions occurred in lateral flow. Also at the subbasin level, phosphorus in organic, sediment, and soluble forms was reduced by 35%, 45%, and 65%, respectively. Suspended sediments increased in 68% of the subbasins. The water yield decreased in 62% of the subbasins. In the Kansas River watershed, the water quality improved significantly with regard to every nitrogen and phosphorus compound. The improvement was

  15. Methane dissociation on Ni(111): A fifteen-dimensional potential energy surface using neural network method

    Science.gov (United States)

    Shen, Xiangjian; Chen, Jun; Zhang, Zhaojun; Shao, Kejie; Zhang, Dong H.

    2015-10-01

    In the present work, we develop a highly accurate, fifteen-dimensional potential energy surface (PES) of CH4 interacting on a rigid flat Ni(111) surface with the methodology of neural network (NN) fit to a database consisted of about 194 208 ab initio density functional theory (DFT) energy points. Some careful tests of the accuracy of the fitting PES are given through the descriptions of the fitting quality, vibrational spectrum of CH4 in vacuum, transition state (TS) geometries as well as the activation barriers. Using a 25-60-60-1 NN structure, we obtain one of the best PESs with the least root mean square errors: 10.11 meV for the entrance region and 17.00 meV for the interaction and product regions. Our PES can reproduce the DFT results very well in particular for the important TS structures. Furthermore, we present the sticking probability S0 of ground state CH4 at the experimental surface temperature using some sudden approximations by Jackson's group. An in-depth explanation is given for the underestimated sticking probability.

  16. Characterization of Methane Degradation and Methane-Degrading Microbes in Alaska Coastal Water

    Energy Technology Data Exchange (ETDEWEB)

    Kirchman, David L. [Univ. of Delaware, Lewes, DE (United States)

    2012-03-29

    The net flux of methane from methane hydrates and other sources to the atmosphere depends on methane degradation as well as methane production and release from geological sources. The goal of this project was to examine methane-degrading archaea and organic carbon oxidizing bacteria in methane-rich and methane-poor sediments of the Beaufort Sea, Alaska. The Beaufort Sea system was sampled as part of a multi-disciplinary expedition (Methane in the Arctic Shelf or MIDAS) in September 2009. Microbial communities were examined by quantitative PCR analyses of 16S rRNA genes and key methane degradation genes (pmoA and mcrA involved in aerobic and anaerobic methane degradation, respectively), tag pyrosequencing of 16S rRNA genes to determine the taxonomic make up of microbes in these sediments, and sequencing of all microbial genes (metagenomes ). The taxonomic and functional make-up of the microbial communities varied with methane concentrations, with some data suggesting higher abundances of potential methane-oxidizing archaea in methane-rich sediments. Sequence analysis of PCR amplicons revealed that most of the mcrA genes were from the ANME-2 group of methane oxidizers. According to metagenomic data, genes involved in methane degradation and other degradation pathways changed with sediment depth along with sulfate and methane concentrations. Most importantly, sulfate reduction genes decreased with depth while the anaerobic methane degradation gene (mcrA) increased along with methane concentrations. The number of potential methane degradation genes (mcrA) was low and inconsistent with other data indicating the large impact of methane on these sediments. The data can be reconciled if a small number of potential methane-oxidizing archaea mediates a large flux of carbon in these sediments. Our study is the first to report metagenomic data from sediments dominated by ANME-2 archaea and is one of the few to examine the entire microbial assemblage potentially involved in

  17. Geology, reservoir engineering and methane hydrate potential of the Walakpa Gas Field, North Slope, Alaska. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Glenn, R.K.; Allen, W.W.

    1992-12-01

    The Walakpa Gas Field, located near the city of Barrow on Alaska`s North Slope, has been proven to be methane-bearing at depths of 2000--2550 feet below sea level. The producing formation is a laterally continuous, south-dipping, Lower Cretaceous shelf sandstone. The updip extent of the reservoir has not been determined by drilling, but probably extends to at least 1900 feet below sea level. Reservoir temperatures in the updip portion of the reservoir may be low enough to allow the presence of in situ methane hydrates. Reservoir net pay however, decreases to the north. Depths to the base of permafrost in the area average 940 feet. Drilling techniques and production configuration in the Walakpa field were designed to minimize formation damage to the reservoir sandstone and to eliminate methane hydrates formed during production. Drilling development of the Walakpa field was a sequential updip and lateral stepout from a previously drilled, structurally lower confirmation well. Reservoir temperature, pressure, and gas chemistry data from the development wells confirm that they have been drilled in the free-methane portion of the reservoir. Future studies in the Walakpa field are planned to determine whether or not a component of the methane production is due to the dissociation of updip in situ hydrates.

  18. An assessment of theoretical methods for nonbonded interactions: comparison to complete basis set limit coupled-cluster potential energy curves for the benzene dimer, the methane dimer, benzene-methane, and benzene-H2S.

    Science.gov (United States)

    Sherrill, C David; Takatani, Tait; Hohenstein, Edward G

    2009-09-24

    Large, correlation-consistent basis sets have been used to very closely approximate the coupled-cluster singles, doubles, and perturbative triples [CCSD(T)] complete basis set potential energy curves of several prototype nonbonded complexes, the sandwich, T-shaped, and parallel-displaced benzene dimers, the methane-benzene complex, the H2S-benzene complex, and the methane dimer. These benchmark potential energy curves are used to assess the performance of several methods for nonbonded interactions, including various spin-component-scaled second-order perturbation theory (SCS-MP2) methods, the spin-component-scaled coupled-cluster singles and doubles method (SCS-CCSD), density functional theory empirically corrected for dispersion (DFT-D), and the meta-generalized-gradient approximation functionals M05-2X and M06-2X. These approaches generally provide good results for the test set, with the SCS methods being somewhat more robust. M05-2X underbinds for the test cases considered, while the performances of DFT-D and M06-2X are similar. Density fitting, dual basis, and local correlation approximations all introduce only small errors in the interaction energies but can speed up the computations significantly, particulary when used in combination.

  19. Characterisation of the biochemical methane potential (BMP) of individual material fractions in Danish source-separated organic household waste.

    Science.gov (United States)

    Naroznova, Irina; Møller, Jacob; Scheutz, Charlotte

    2016-04-01

    This study is dedicated to characterising the chemical composition and biochemical methane potential (BMP) of individual material fractions in untreated Danish source-separated organic household waste (SSOHW). First, data on SSOHW in different countries, available in the literature, were evaluated and then, secondly, laboratory analyses for eight organic material fractions comprising Danish SSOHW were conducted. No data were found in the literature that fully covered the objectives of the present study. Based on laboratory analyses, all fractions were assigned according to their specific properties in relation to BMP, protein content, lipids, lignocellulose biofibres and easily degradable carbohydrates (carbohydrates other than lignocellulose biofibres). The three components in lignocellulose biofibres, i.e. lignin, cellulose and hemicellulose, were differentiated, and theoretical BMP (TBMP) and material degradability (BMP from laboratory incubation tests divided by TBMP) were expressed. Moreover, the degradability of lignocellulose biofibres (the share of volatile lignocellulose biofibre solids degraded in laboratory incubation tests) was calculated. Finally, BMP for average SSOHW composition in Denmark (untreated) was calculated, and the BMP contribution of the individual material fractions was then evaluated. Material fractions of the two general waste types, defined as "food waste" and "fibre-rich waste," were found to be anaerobically degradable with considerable BMP. Material degradability of material fractions such as vegetation waste, moulded fibres, animal straw, dirty paper and dirty cardboard, however, was constrained by lignin content. BMP for overall SSOHW (untreated) was 404 mL CH4 per g VS, which might increase if the relative content of material fractions, such as animal and vegetable food waste, kitchen tissue and dirty paper in the waste, becomes larger.

  20. Water storage equity and safety assurance policy to mitigate potential 'dual-extreme cumulative threats' in agricultural catchments

    Science.gov (United States)

    Pisaniello, John D.; Tingey-Holyoak, Joanne L.

    2017-02-01

    Farm dams that are not managed properly at the individual level can create water storage equity and safety threats to downstream communities and the environment that aggregate at the catchment level: a potential 'dual-extreme cumulative' problem. The paper provides indicative evidence and develops understanding of this novel phenomenon and associated policy needs within the Australian setting comprising dual hydrologic extremes of floods and droughts, further exacerbated by climate change. This is achieved through comparative case studies involving surveys of both dam owner perceptions and dam management practices in four States representing a complete range of integrated policy approaches from weak to strong. Survey results find most farmers do not believe dam maintenance is important, will undertake spillway blocking and do not plan for emergencies. These results are supported by physical on-site findings of farmers neglecting dams and blocking or under-designing spillways, in turn storing more water than they are entitled and creating unsafe dams at both the individual and cumulative levels. From detailed cross-case comparative assessment against policy context, it emerges that on-farm perceptions and practices form a range of 'acceptability' of dam management that directly reflects policy strength and integration in each setting. The paper advances the international small dams policy, agricultural water management and hydrology literatures, evidencing the need for effective integrated policy to mitigate dual extreme cumulative threats. Importantly, guidance is provided to jurisdictions internationally with high inter-annual rainfall variation on how best to design integrated policy that can achieve both water storage equity and safety in agricultural catchments.

  1. Valuing the Ozone-Related Health Benefits of Methane Emission Controls

    Energy Technology Data Exchange (ETDEWEB)

    Sarofim, Marcus C.; Waldhoff, Stephanie T.; Anenberg, Susan C.

    2015-06-29

    Methane is a greenhouse gas that oxidizes to form ground-level ozone, itself a greenhouse gas and a health-harmful air pollutant. Reducing methane emissions will both slow anthropogenic climate change and reduce ozone-related mortality. We estimate the benefits of reducing methane emissions anywhere in the world for ozone-related premature mortality globally and for eight geographic regions. Our methods are consistent with those used by the U.S. Government to estimate the Social Cost of Carbon (SCC). We find that the global short- and long-term premature mortality benefits due to reduced ozone production from methane mitigation are (2011)$790 and $1775 per tonne methane, respectively. These correspond to approximately 70% and 150% of the valuation of methane’s global climate impacts using the SCC after extrapolating from carbon dioxide to methane using Global Warming Potential (GWP) estimates. Results are most sensitive to the choice of VSL and increase for emission years further in the future. Regionally, most of the global mortality benefits accrue in Asia, but 10% accrue in the United States. This methodology can be used to assess the benefits of methane emission reductions anywhere in the world, including those achieved by national and multinational policies.

  2. Estimating methane gas generation from Devil's swamp landfill using greenhouse gas emission models

    Science.gov (United States)

    Adeyemi, Ayodeji Thompson

    Greenhouse gas (GHG) has been a key issue in the study, design, and management of landfills. Landfill gas (LFG) is considered either as a significant source of renewable energy (if extracted and processed accordingly) or significant source of pollution and risk (if not mitigated or processed). A municipal solid waste (MSW) landfill emits a significant amount of methane, a potent GHG. Thus, quantification and mitigation of GHG emissions is an important area of study in engineering and other sciences related to landfill technology and management. The present study will focus on estimating methane generation from Devils swamp landfill (DSLF), a closed landfill in Baton Rouge, LA. The landfill operated for 53 years (1940-1993) and contains both industrial and municipal waste products. Since the Clean Air Act of 1963, landfills are now classified as New Source Performance Standard (NSPS) waste (i.e., waste that will decompose to generate LFG). Currently, the DSLF is being used as source of renewable energy through the "Waste to Energy" program. For this study, to estimate the methane potential in the DSLF, it is important to determine the characteristics and classification of the landfill's wastes. The study uses and compares different GHG modeling tools---LandGEM, a multiphase model, and a simple first-order model---to estimate methane gas emission and compare results with the actual emissions from the DSLF. The sensitivity of the methane generation rate was analyzed by the methane generation models to assess the effects of variables such as initial conditions, specific growth rate, and reaction rate constants. The study concludes that methane (L0) and initial organic concentration in waste (k) are the most important parameters when estimating methane generation using the models.

  3. Suppressing methane emission and global warming potential from rice fields through intermittent drainage and green biomass amendment

    NARCIS (Netherlands)

    Haque, Md. M.; Biswas, J. C.; Kim, S. Y.; Kim, P. J.

    2016-01-01

    Winter cover crops are recommended to improve soil quality and carbon sequestration, although their use as green manure can significantly increase methane (CH4) emission from paddy soils. Soil management practices can be used to reduce CH4 emission from paddy soils, but intermittent drainage is rega

  4. Stimulation of methane oxidation potential and effects on vegetation growth by bottom ash addition in a landfill final evapotranspiration cover

    NARCIS (Netherlands)

    Kim, G.W.; Ho, A.; Kim, P.J.; Kim, Sang Yun

    2016-01-01

    The landfilling of municipal solid waste is a significant source of atmospheric methane (CH4), contributing up to 20% of total anthropogenic CH4 emissions. The evapotranspiration (ET) cover system, an alternative final cover system in waste landfills, has been considered to be a promising way to mit

  5. Stimulation of methane oxidation potential and effects on vegetation growth by bottom ash addition in a landfill final evapotranspiration cover

    NARCIS (Netherlands)

    Kim, G.W.; Ho, A.; Kim, P.J.; Kim, Sang Yun

    2016-01-01

    The landfilling of municipal solid waste is a significant source of atmospheric methane (CH4), contributing up to 20% of total anthropogenic CH4 emissions. The evapotranspiration (ET) cover system, an alternative final cover system in waste landfills, has been considered to be a promising way to

  6. Stimulation of methane oxidation potential and effects on vegetation growth by bottom ash addition in a landfill final evapotranspiration cover

    NARCIS (Netherlands)

    Kim, G.W.; Ho, A.; Kim, P.J.; Kim, Sang Yun

    2016-01-01

    The landfilling of municipal solid waste is a significant source of atmospheric methane (CH4), contributing up to 20% of total anthropogenic CH4 emissions. The evapotranspiration (ET) cover system, an alternative final cover system in waste landfills, has been considered to be a promising way to mit

  7. Assessment and mitigation of the environmental burdens to air from land applied food-based digestate.

    Science.gov (United States)

    Tiwary, A; Williams, I D; Pant, D C; Kishore, V V N

    2015-08-01

    Anaerobic digestion (AD) of putrescible urban waste for energy recovery has seen rapid growth over recent years. In order to ascertain its systems scale sustainability, however, determination of the environmental fate of the large volume of digestate generated during the process is indispensable. This paper evaluates the environmental burdens to air associated with land applied food-based digestate in terms of primary pollutants (ammonia, nitrogen dioxide) and greenhouse gases (methane and nitrous oxide). The assessments have been made in two stages - first, the emissions from surface application of food-based digestate are quantified for the business as usual (BAU). In the next step, environmental burden minimisation potentials for the following three mitigation measures are estimated - mixed waste digestate (MWD), soil-incorporated digestate (SID), and post-methanated digestate (PMD). Overall, the mitigation scenarios demonstrated considerable NH3, CH4 and N2O burden minimisation potentials, with positive implications for both climate change and urban pollution.

  8. Evaluating potential chlorinated methanes degradation mechanisms and treatments in interception trenches filled with concrete-based construction wastes

    Science.gov (United States)

    Rodríguez-Fernandez, Diana; Torrentó, Clara; Rosell, Mònica; Audí-Miró, Carme; Soler, Albert

    2014-05-01

    conditions in the trenches with in situ chemical oxidation (ISCO), which would be able to remove the rest of the accompanying pollutants, is proposed and merits evaluation. Preliminary batch experiments were performed to evaluate the feasibility of different chemical oxidation reactions (permanganate, persulphate, hydrogen peroxide and Fenton) on the complex contaminated recharge water which were, in general, more effective for degrading the chlorinated ethenes than for the chlorinated methanes (Torrentó et al. EGU 2012). Therefore, this study seeks to improve the understanding of CF and CT degradation mechanisms/processes that are going on in the interception trenches as well as to select between the two most effective chemical oxidation remediation treatments (persulphate and permanganate) taking into account their efficiency respect the chlorinated methanes removal, the generated acute toxicity and the applicability of the carbon isotopic fractionation as an indicator of the effectiveness of the future in situ remediation. Additionally, ongoing batch experiments are expected to elucidate if CT is undergoing abiotic reductive dechlorination by Fe-bearing minerals such as hydrophobic green rust (Ayala-Luis et al., 2012) which transform CT into non-chlorinated substances such as formic acid and carbon monoxide. This unstable iron compound might be formed in the interception trenches during chloride induced corrosion of iron mineral phases present in the concrete-based construction wastes (Sagoe-Crentsil and Glasser, 1993). The role of other minerals like iron oxy-hydroxides, carbonates or sulphides cannot be discarded at all. The potential of δ13C values to assess the efficiency of this abiotic CT degradation reaction will be also evaluated. References Ayala-Luis, K.; Cooper, N.; Bender C. and Hansen. H. (2012) Efficient dechlorination of carbon tetrachloride by hydrophobic green rust intercaled with dodecanoate anions. Environmental Science & Technology 46, 3390

  9. Systems level insights into alternate methane cycling modes in a freshwater lake via community transcriptomics, metabolomics and nano-SIMS analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lidstrom, Mary E. [Univ. of Washington, Seattle, WA (United States); Chistoserdova, Ludmila [Univ. of Washington, Seattle, WA (United States); Kalyuzhnaya, Marina G. [Univ. of Washington, Seattle, WA (United States); Orphan, Victoria J. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Beck, David A. [Univ. of Washington, Seattle, WA (United States)

    2014-08-07

    The research conducted as part of this project contributes significantly to the understanding of the microbes and their activities involved in methane metabolism in freshwater lake sediments and in the environment in a more global sense. Significant new insights have been gained into the identity of the species that are most active in methane oxidation. New concepts have been developed based on the new data on how these organisms metabolize methane, impacting not only environmental microbiology but also biotechnology, including biotechnology of next generation biofuels. Novel approaches have been developed for studying functional microbial communities, via holistic approaches, such as metagenomics, metatrancriptomics and metabolite analysis. As a result, a novel outlook has been obtained at how such communities operate in nature. Understanding methane-oxidizing communities in lakes and other environments is of significant benefit to the public, in terms of methane emission mitigation and in terms of potential biotechnological applications.

  10. Influence of niche differentiation on the abundance of methanogenic archaea and methane production potential in natural wetland ecosystems across China

    Directory of Open Access Journals (Sweden)

    D. Liu

    2010-10-01

    Full Text Available Methane (CH4 emissions from natural wetland ecosystems exhibit large spatial variability. To understand the underlying factors that induce differences in CH4 emissions from natural wetlands around China, we measured the CH4 production potential and the abundance of methanogenic archaea in vertical profile soils sampled from the Poyang wetland in the subtropical zone, the Hongze wetland in the warm temperate zone, the Sanjiang marsh in the cold temperate zone, and the Ruoergai peatland in the Qinghai-Tibetan Plateau. The top soil layer had the highest population of methanogens (1.07−8.29×109 cells g−1 soil in all wetlands except the Ruoergai peatland and exhibited the maximum CH4 production potential measured at the mean in situ summer temperature. There is a significant logarithmic correlation between the abundance of methanogenic archaea and the soil organic carbon (R2=0.718, P<0.001, n=13 and between the abundance of methanogenic archaea and the total nitrogen concentrations (R2=0.758, P<0.001, n=13 in wetland soils. This indicates that the amount of soil organic carbon may affect the population of methanogens in wetland ecosystems. While the CH4 production potential is not significantly related to methanogen population (R2=0.011, P>0.05, n=13, it is related to the dissolved organic carbon concentration (R2=0.305, P=0.05, n=13. This suggests that the methanogen population is not an effective index for predicting the CH4 production in wetland ecosystems. The CH4 production rate of the top soil layer increases with increasing latitude, from 274 μg CH4 kg−1 soil d−1 in the Poyang wetland to 665 μg CH4 kg−1 soil d−1 in the Carex lasiocarpa

  11. The potential of bacteria isolated from ruminal contents of seaweed-eating North Ronaldsay sheep to hydrolyse seaweed components and produce methane by anaerobic digestion in vitro.

    Science.gov (United States)

    Williams, Allan G; Withers, Susan; Sutherland, Alastair D

    2013-01-01

    The production of methane biofuel from seaweeds is limited by the hydrolysis of polysaccharides. The rumen microbiota of seaweed-eating North Ronaldsay sheep was studied for polysaccharidic bacterial isolates degrading brown-seaweed polysaccharides. Only nine isolates out of 65 utilized >90% of the polysaccharide they were isolated on. The nine isolates (eight Prevotella spp. and one Clostridium butyricum) utilized whole Laminaria hyperborea extract and a range of seaweed polysaccharides, including alginate (seven out of nine isolates), laminarin and carboxymethylcellulose (eight out of nine isolates); while two out of nine isolates additionally hydrolysed fucoidan to some extent. Crude enzyme extracts from three of the isolates studied further had diverse glycosidases and polysaccharidase activities; particularly against laminarin and alginate (two isolates were shown to have alginate lyase activity) and notably fucoidan and carageenan (one isolate). In serial culture rumen microbiota hydrolysed a range of seaweed polysaccharides (fucoidan to a notably lesser degree) and homogenates of L. hyperborea, mixed Fucus spp. and Ascophyllum nodosum to produce methane and acetate. The rumen microbiota and isolates represent potential adjunct organisms or enzymes which may improve hydrolysis of seaweed components and thus improve the efficiency of seaweed anaerobic digestion for methane biofuel production.

  12. Non-methane hydrocarbons (NMHCs) and their contribution to ozone formation potential in a petrochemical industrialized city, Northwest China

    Science.gov (United States)

    Jia, Chenhui; Mao, Xiaoxuan; Huang, Tao; Liang, Xiaoxue; Wang, Yanan; Shen, Yanjie; Jiang, Wanyanhan; Wang, Huiqin; Bai, Zhilin; Ma, Minquan; Yu, Zhousuo; Ma, Jianmin; Gao, Hong

    2016-03-01

    Hourly air concentrations of fifty-three non-methane hydrocarbons (NMHCs) were measured at downtown and suburb of Lanzhou, a petrochemical industrialized city, Northwest China in 2013. The measured data were used to investigate the seasonal characteristics of NMHCs air pollution and their contributions to the ozone formation in Lanzhou. Annually averaged NMHCs concentration was 38.29 ppbv in downtown Lanzhou. Among 53 NMHCs, alkanes, alkenes, and aromatics accounted for 57%, 23% and 20% of the total NMHCs air concentration, respectively. The atmospheric levels of toluene and propane with mean values of 4.62 and 4.56 ppbv were higher than other NMHCs, respectively. The ambient levels of NMHCs in downtown Lanzhou were compared with measured NMHCs data collected at a suburban site of Lanzhou, located near a large-scale petrochemical industry. Results show that the levels of alkanes, alkenes, and aromatics in downtown Lanzhou were lower by factors of 3-11 than that in west suburb of the city. O3-isopleth plots show that ozone was formed in VOCs control area in downtown Lanzhou and NOx control area at the west suburban site during the summertime. Propylene-equivalent (Prop-Equiv) concentration and the maximum incremental reactivity (MIR) in downtown Lanzhou indicate that cis-2-butene, propylene, and m/p-xylene were the first three compounds contributing to ozone formation potentials whereas in the petrochemical industrialized west suburb, ethane, propene, and trans-2-Butene played more important role in the summertime ozone formation. Principal component analysis (PCA) and multiple linear regression (MLR) were further applied to identify the dominant emission sources and examine their fractions in total NMHCs. Results suggest that vehicle emission, solvent usage, and industrial activities were major sources of NMHCs in the city, accounting for 58.34%, 22.19%, and 19.47% of the total monitored NMHCs in downtown Lanzhou, respectively. In the west suburb of the city

  13. Screening of plants from diversified natural grasslands for their potential to combine high digestibility, and low methane and ammonia production.

    Science.gov (United States)

    Macheboeuf, D; Coudert, L; Bergeault, R; Lalière, G; Niderkorn, V

    2014-11-01

    A total of 156 plant species from 35 botanical families collected from diversified grasslands in the French Massif Central were screened in vitro for their potential to combine high nutritive value for ruminants and a reduced impact on the environment. The vegetative part of plants were analyzed for their chemical composition and incubated in a batch system containing buffered rumen fluid at 39°C for 24 h. The gas production and composition were recorded, and the fermentation end-product concentrations in the incubation medium and the in vitro true organic matter digestibility (IVTOMD) were determined. The results were expressed relative to perennial ryegrass (PRG) values used as a reference. We observed that no relationship between methane (CH4) and volatile fatty acids (VFA) was evidenced for 12 plants, the fermentation of these plants producing significantly less CH4 for a similar level of VFA production. In all, 13 plants showed 50% less CH4 production per unit of organic matter truly digested (OMTD) than PRG. Among these plants, two reduced CH4 by more than 80% and four species had an IVTOMD higher than 80%. The underlying modes of action seem to be different among plants: some result in an accumulation of H2 in the fermentation gas, but others do not. In terms of nitrogen (N) use efficiency, the fermentation of 37 plants halved the ratio between ammonia (N-NH3) and plant N content compared with PRG, of which six showed a complete absence of N-NH3 in the medium. Among these plants, four maintained the IVTDMO at values not significantly different from PRG (P>0.05). Considering the multi-criteria selection, 16 plants showed simultaneously a reduction of more than 80% in N-NH3 production and 30% in CH4 emission per unit of OMTD compared with PRG, including three with an IVTOMD higher than 80%. Overall, the botanical families that reduced simultaneously CH4 and N-NH3 most efficiently were the Rosaceae, Onagraceae, Polygonaceae and Dipsacaceae. The Onagraceae also

  14. Arctic methane

    NARCIS (Netherlands)

    Dyupina, E.; Amstel, van A.R.

    2013-01-01

    What are the risks of a runaway greenhouse effect from methane release from hydrates in the Arctic? In January 2013, a dramatic increase of methane concentration up to 2000 ppb has been measured over the Arctic north of Norway in the Barents Sea. The global average being 1750 ppb. It has been

  15. Arctic methane

    NARCIS (Netherlands)

    Dyupina, E.; Amstel, van A.R.

    2013-01-01

    What are the risks of a runaway greenhouse effect from methane release from hydrates in the Arctic? In January 2013, a dramatic increase of methane concentration up to 2000 ppb has been measured over the Arctic north of Norway in the Barents Sea. The global average being 1750 ppb. It has been sugges

  16. A reactive transport model for the geochemical response, detection and potential mitigation of CO2 leakage into a confined aquifer

    Science.gov (United States)

    Maher, K.; Druhan, J. L.; Vialle, S.; Benson, S. M.; Agarwal, A.

    2013-12-01

    Long-term storage of anthropogenic CO2 in the subsurface generally assumes that caprock formations will serve as physical barriers to upward migration of CO2. Stability and coherence of the caprocks are thus important criteria for site selection, but caprock integritycannot be guaranteed with total certainty over the lifetime of the project. As a result, carbon capture and storage projects require reliable techniques to monitor geologic storage sites for newly formed leaks, and the ability to rapidly deploy mitigation measures should leakage occur. Here, we present two-dimensional reactive transport simulations to evaluate the hydrogeochemical characteristics of a newly formed CO2 leak into an overlying reservoir. Simulations use the ToughReact multi-component reactive transport code and hypothetical reservoir characteristics. We focus on the comparatively short time period of days to months following formation of the leak to consider (1) geochemical shifts in formation water indicative of the leak, (2) hydrodynamics of pumping wells in the vicinity of the leak, and (3) delivery of a sealant to the leak through an adjacent well bore. Our results suggest that characteristic shifts in pH and dissolved inorganic carbon might be detected in down-gradient mentoring wells prior to the breakthrough of CO2, and could offer a potential means of identifying small and newly formed leaks. Injecting water into the aquifer through pumping wells in the vicinity of the leak provides a hydrodynamic control that can prevent CO2 from reaching the top of the reservoir, but this action will likely have only minor influence on the rate of leakage through the caprock defect. Injection of a hypothetical sealant through an adjacent pumping well is considered using an aqueous solute with pH-dependent equilibrium constraints such that the species is soluble in the basic pH range but forms a precipitate at neutral to acidic pH conditions associated with CO2-rich water. Injection of this

  17. Bio methane in the cogeneration market and heating market. Status quo, potentials and recommendations for an accelerated market penetration; Biomethan im KWK- und Waermemarkt. Status Quo, Potenziale und Handlungsempfehlungen fuer eine beschleunigte Marktdurchdringung

    Energy Technology Data Exchange (ETDEWEB)

    Herr, Michael; Rostek, Sandra (comps.)

    2010-07-15

    The current contribution of the German Energy Agency (Berlin, Federal Republic of Germany) reports on the present sale situation of bio methane on the coupled and uncoupled heating market. The contribution clarifies, why the existing support measures do not stimulate the demand for bio methane in the necessary order of magnitude. Without adjustment of the legal framework neither the considerable sales potentials can be established, nor the targets for the development of the biogas feeding can be achieved approximately. The low demand on bio methane led to a planning stop on the producer side. Direct need for action is required.

  18. Energy sector methane recovery and use: the importance of policy

    Energy Technology Data Exchange (ETDEWEB)

    Tom Kerr; Michelle Hershman

    2009-08-15

    To raise awareness about appropriate policy options to advance methane recovery and use in the energy sector, the IEA has conducted a series of analyses and studies over the past few years. This report continues IEA efforts by providing policy makers with examples and best practices in methane mitigation policy design and implementation. This report offers an overview of four types of methane mitigation projects that have the strongest links to the energy sector: oil and gas methane recovery and reduction of leaks and losses; coal mine methane; landfill methane; and manure methane recovery and use. It identifies successful policies that have been used to advance these important projects. This information is intended to guide policy makers as they search for low-cost, near-term solutions to climate change. 38 refs., 10 figs., 1 app.

  19. A Low Temperature Eutectic Methane-Ethane Liquid: A Potential Geologic Fluid in the Outermost Solar System

    Science.gov (United States)

    Thompson, Garrett Leland; Hanley, Jennifer; Grundy, Will; Tegler, Stephen C.; Roe, Henry G.; Lindberg, Gerrick Eugene; Trilling, David E.

    2016-10-01

    Many icy bodies and moons in the solar system contain methane and ethane, including Titan, Triton, Pluto, Eris, Makemake, and likely others. The material properties of these species and their interactions with one another are still inadequately characterized. To provide insight into the behaviors of these species we conducted a series of laboratory experiments to map the liquidus line as a function of temperature and composition. The interaction of ethane and methane yields a eutectic mixture and depresses the freezing point to ~72 K, almost 20 K colder than the normal freezing points of either pure species. The eutectic composition is 64% CH4 and 36% C2H6. This phenomenon may enable geological processes involving liquids in the near surface environments of bodies once thought too cold and/or that have surface pressures too low to support liquid phases. The addition of other cosmochemically abundant species may suppress freezing points even further (see Hanley et al., this conference).

  20. Does cryptic microbiota mitigate pine resistance to an invasive beetle-fungus complex? Implications for invasion potential.

    Science.gov (United States)

    Cheng, Chihang; Xu, Letian; Xu, Dandan; Lou, Qiaozhe; Lu, Min; Sun, Jianghua

    2016-09-13

    Microbial symbionts are known to assist exotic pests in their colonization of new host plants. However, there has been little evidence linking symbiotic invasion success to mechanisms for mitigation of native plant resistance. The red turpentine beetle (RTB) was introduced with a fungus, Leptographium procerum, to China from the United States and became a destructively invasive symbiotic complex in natural Pinus tabuliformis forests. Here, we report that three Chinese-resident fungi, newly acquired by RTB in China, induce high levels of a phenolic defensive chemical, naringenin, in pines. This invasive beetle-fungus complex is suppressed by elevated levels of naringenin. However, cryptic microbiotas in RTB galleries strongly degrade naringenin, and pinitol, the main soluble carbohydrate of P. tabuliformis, is retained in L. procerum-infected phloem and facilitate naringenin biodegradation by the microbiotas. These results demonstrate that cryptic microbiota mitigates native host plant phenolic resistance to an invasive symbiotic complex, suggesting a putative mechanism for reduced biotic resistance to symbiotic invasion.

  1. The potential of carbon sequestration to mitigate against climate change in forests and agro ecosystems of Zimbabwe

    OpenAIRE

    2014-01-01

    Climate change adversely affects human livelihoods and the environment through alteration of temperatures, rainfall patterns, sea level rise and ecosystem productivity. Developing countries are more vulnerable to climate change because they directly depend on agriculture and natural ecosystem products for their livelihoods. Mitigation of climate change impacts includes practices that can store carbon (C) in soil and biomass thus, reducing concentrations of atmospheric carbon dioxide (CO2) and...

  2. Modeling of methane bubbles released from large sea-floor area: Condition required for methane emission to the atmosphere

    OpenAIRE

    Yamamoto, A.; Yamanaka, Y.; Tajika, E.

    2009-01-01

    Massive methane release from sea-floor sediments due to decomposition of methane hydrate, and thermal decomposition of organic matter by volcanic outgassing, is a potential contributor to global warming. However, the degree of global warming has not been estimated due to uncertainty over the proportion of methane flux from the sea-floor to reach the atmosphere. Massive methane release from a large sea-floor area would result in methane-saturated seawater, thus some methane would reach the atm...

  3. Methane adsorption on activated carbon

    NARCIS (Netherlands)

    Perl, Andras; Koopman, Folkert; Jansen, Peter; Rooij, Marietta de; Gemert, Wim van

    2014-01-01

    Methane storage in adsorbed form is a promising way to effectively and safely store fuel for vehicular transportation or for any other potential application. In a solid adsorbent, nanometer wide pores can trap methane by van der Waals forces as high density fluid at low pressure and room temperature

  4. Methane content and potential of biogas' production by manure of pigs fed with corn or sorghum-based diets in different phases

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, Adelia Pereira; Lucas Junior, Jorge de; Thomaz, Maria Cristina; Fukayama, Ellen Hatsumi [Universidade Estadual Paulista (UNESP), Jaboticabal, SP (Brazil)

    2008-07-01

    The aim of this trial was to value the methane content and potential of biogas' production by manure of pigs fed with corn or sorghum-based diets (energy's source) in different phases. The manures were daily collected, diluted in water and homogeneous. Were used 267 mL of influent with 6% total solids concentration for supply of continuous-flow laboratory anaerobic digesters, with 30 days of detention time (DT) and temperature of 35 deg C. The experiment was completely randomized design with 2 treatments (corn or sorghum) and 3 phases of growth (initial x growing x finishing) in 10 replications (anaerobic digesters). The methane contents by manure of pigs fed with corn were greater (p<0.01) than pigs fed with sorghum (65.19 and 67.32%) on the phases of growing and finishing, respectively. The most potential of biogas' production (0.181, 0.138 and 0.162 m{sup 3}/kg of manure) was with manure of pigs fed with corn on the phases of initial, growing and finishing, respectively (p<0.01). Considering all the phases, the most potential of biogas' production (p<0.01) was observed in the initial phase, in both treatments. (author)

  5. Methyl-coenzyme M reductase A as an indicator to estimate methane production from dairy cows.

    Science.gov (United States)

    Aguinaga Casañas, M A; Rangkasenee, N; Krattenmacher, N; Thaller, G; Metges, C C; Kuhla, B

    2015-06-01

    The evaluation of greenhouse gas mitigation strategies requires the quantitative assessment of individual methane production. Because methane measurement in respiration chambers is highly accurate, but also comprises various disadvantages such as limited capacity and high costs, the establishment of an indicator for estimating methane production of individual ruminants would provide an alternative to direct methane measurement. Methyl-coenzyme M reductase is involved in methanogenesis and the subunit α of methyl-coenzyme M reductase is encoded by the mcrA gene of rumen archaea. We therefore examined the relationship between methane emissions of Holstein dairy cows measured in respiration chambers with 2 different diets (high- and medium-concentrate diet) and the mcrA DNA and mcrA cDNA abundance determined from corresponding rumen fluid samples. Whole-body methane production per kilogram of dry matter intake and mcrA DNA normalized to the abundance of the rrs gene coding for 16S rRNA correlated significantly when using qmcrA primers. Use of qmcrA primers also revealed linear correlation between mcrA DNA copy number and methane yield. Regression analyses based on normalized mcrA cDNA abundances revealed no significant linear correlation with methane production per kilogram of dry matter intake. Furthermore, the correlations between normalized mcrA DNA abundance and the rumen fluid concentration of acetic and isobutyric acid were positive, whereas the correlations with propionic and lactic acid were negative. These data suggest that the mcrA DNA approach based on qmcrA primers could potentially be a molecular proxy for methane yield after further refinement.

  6. [Copper in methane oxidation: a review].

    Science.gov (United States)

    Su, Yao; Kong, Jiao-Yan; Zhang, Xuan; Xia, Fang-Fang; He, Ruo

    2014-04-01

    Methane bio-oxidation plays an important role in the global methane balance and warming mitigation, while copper has a crucial function in methane bio-oxidation. On one side, copper is known to be a key factor in regulating the expression of the genes encoding the two forms of methane monooxygenases (MMOs) and is the essential metal element of the particulate methane monooxygenase (pMMO). On the other side, the content and fractionation of copper in the environment have great effects on the distribution of methanotrophs and their metabolic capability of methane and non-methane organic compounds, as well as on the copper-specific uptake systems in methanotrophs. Thus, it is meaningful to know the role of copper in methane bio-oxidation for comprehensive understanding of this process and is valuable for guiding the application of methanotrophs in greenhouse gas removal and pollution remediation. In this paper, the roles of copper in methane oxidation were reviewed, including the effect of copper on methanotrophic community structure and activity, the expression and activity of MMOs as well as the copper uptake systems in methanotrophs. The future studies of copper and methane oxidation were also discussed.

  7. Effect of ultrasound, low-temperature thermal and alkali pre-treatments on waste activated sludge rheology, hygienization and methane potential.

    Science.gov (United States)

    Ruiz-Hernando, M; Martín-Díaz, J; Labanda, J; Mata-Alvarez, J; Llorens, J; Lucena, F; Astals, S

    2014-09-15

    Waste activated sludge is slower to biodegrade under anaerobic conditions than is primary sludge due to the glycan strands present in microbial cell walls. The use of pre-treatments may help to disrupt cell membranes and improve waste activated sludge biodegradability. In the present study, the effect of ultrasound, low-temperature thermal and alkali pre-treatments on the rheology, hygienization and biodegradability of waste activated sludge was evaluated. The optimum condition of each pre-treatment was selected based on rheological criteria (reduction of steady state viscosity) and hygienization levels (reduction of Escherichia coli, somatic coliphages and spores of sulfite-reducing clostridia). The three pre-treatments were able to reduce the viscosity of the sludge, and this reduction was greater with increasing treatment intensity. However, only the alkali and thermal conditioning allowed the hygienization of the sludge, whereas the ultrasonication did not exhibit any notorious effect on microbial indicators populations. The selected optimum conditions were as follows: 27,000 kJ/kg TS for the ultrasound, 80 °C during 15 min for the thermal and 157 g NaOH/kg TS for the alkali. Afterward, the specific methane production was evaluated through biomethane potential tests at the specified optimum conditions. The alkali pre-treatment exhibited the greatest methane production increase (34%) followed by the ultrasonication (13%), whereas the thermal pre-treatment presented a methane potential similar to the untreated sludge. Finally, an assessment of the different treatment scenarios was conducted considering the results together with an energy balance, which revealed that the ultrasound and alkali treatments entailed higher costs. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Mitigation of global greenhouse gas emissions from waste: conclusions and strategies from the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report

    DEFF Research Database (Denmark)

    Bogner, J.P.; Pipatti, R.; Hashimoto, S.

    2008-01-01

    (CO2), methane (CH4), nitrous oxide (N2O), and F-gases normalized according to their 100-year global warming potentials (GWP)). The CH4 from landfills and wastewater collectively accounted for about 90% of waste sector emissions, or about 18% of global anthropogenic methane emissions (which were about...... protection, and sustainable development co-benefits, existing waste management practices can provide effective mitigation of GHG emissions from this sector. Current mitigation technologies include landfill gas recovery, improved landfill practices, and engineered wastewater management. In addition...... quantity and characteristics, cost and financing issues, infrastructure requirements including available land area, collection and transport considerations, and regulatory constraints. Existing studies on mitigation potentials and costs for the waste sector tend to focus on landfill CH4 as the baseline...

  9. RENEWABLE ENERGY SOURCES AND THEIR POTENTIAL ROLE IN MITIGATION OF CLIMATE CHANGES AND AS A SUSTAINABLE DEVELOPMENT DRIVER IN BOSNIA AND HERZEGOVINA

    Directory of Open Access Journals (Sweden)

    Petar M Gvero

    2010-01-01

    Full Text Available Bosnia and Herzegovina have significant physical potential regarding to renewable energy sources. Hydro, biomass, geothermal, wind, and solar potential can play important role in the whole state economy. Bosnia and Herzegovina is Non-Annex I country according to UNFCCC and according to that it is obligated to participate in the global efforts in order to reduce green house gases emission. This paper gives some analysis of the physical, technological, economic, and market potential of renewable energy sources in Bosnia and Herzegovina and their potential role in mitigation of climate changes. Paper also gives the analysis of the potential connections between renewable energy sources and sustainable development of the economy, taking in to consideration specific political structure of the state. Bosnia and Herzegovina is consisting from two entities: Republic of Srpska and Federation of Bosnia and Herzegovina, and Brcko District; energy sector and climate changes mitigation measures are under their jurisdiction. According to that some of this paper results can be useful for the improvement of entity and state strategies with the final aim to place renewable energy sources on the right position, as some of the major economy drivers, not only in Bosnia and Herzegovina, but in whole region.

  10. Methane production and methane consumption: a review of processes underlying wetland methane fluxes.

    NARCIS (Netherlands)

    Segers, R.

    1998-01-01

    Potential rates of both methane production and methane consumption vary over three orders of magnitude and their distribution is skew. These rates are weakly correlated with ecosystem type, incubation temperature, in situ aeration, latitude, depth and distance to oxic/anoxic interface. Anaerobic

  11. Methane production and methane consumption: a review of processes underlying wetland methane fluxes.

    NARCIS (Netherlands)

    Segers, R.

    1998-01-01

    Potential rates of both methane production and methane consumption vary over three orders of magnitude and their distribution is skew. These rates are weakly correlated with ecosystem type, incubation temperature, in situ aeration, latitude, depth and distance to oxic/anoxic interface. Anaerobic car

  12. The global methane budget 2000-2012

    Science.gov (United States)

    Saunois, Marielle; Bousquet, Philippe; Poulter, Ben; Peregon, Anna; Ciais, Philippe; Canadell, Josep G.; Dlugokencky, Edward J.; Etiope, Giuseppe; Bastviken, David; Houweling, Sander; Janssens-Maenhout, Greet; Tubiello, Francesco N.; Castaldi, Simona; Jackson, Robert B.; Alexe, Mihai; Arora, Vivek K.; Beerling, David J.; Bergamaschi, Peter; Blake, Donald R.; Brailsford, Gordon; Brovkin, Victor; Bruhwiler, Lori; Crevoisier, Cyril; Crill, Patrick; Covey, Kristofer; Curry, Charles; Frankenberg, Christian; Gedney, Nicola; Höglund-Isaksson, Lena; Ishizawa, Misa; Ito, Akihiko; Joos, Fortunat; Kim, Heon-Sook; Kleinen, Thomas; Krummel, Paul; Lamarque, Jean-François; Langenfelds, Ray; Locatelli, Robin; Machida, Toshinobu; Maksyutov, Shamil; McDonald, Kyle C.; Marshall, Julia; Melton, Joe R.; Morino, Isamu; Naik, Vaishali; O'Doherty, Simon; Parmentier, Frans-Jan W.; Patra, Prabir K.; Peng, Changhui; Peng, Shushi; Peters, Glen P.; Pison, Isabelle; Prigent, Catherine; Prinn, Ronald; Ramonet, Michel; Riley, William J.; Saito, Makoto; Santini, Monia; Schroeder, Ronny; Simpson, Isobel J.; Spahni, Renato; Steele, Paul; Takizawa, Atsushi; Thornton, Brett F.; Tian, Hanqin; Tohjima, Yasunori; Viovy, Nicolas; Voulgarakis, Apostolos; van Weele, Michiel; van der Werf, Guido R.; Weiss, Ray; Wiedinmyer, Christine; Wilton, David J.; Wiltshire, Andy; Worthy, Doug; Wunch, Debra; Xu, Xiyan; Yoshida, Yukio; Zhang, Bowen; Zhang, Zhen; Zhu, Qiuan

    2016-12-01

    The global methane (CH4) budget is becoming an increasingly important component for managing realistic pathways to mitigate climate change. This relevance, due to a shorter atmospheric lifetime and a stronger warming potential than carbon dioxide, is challenged by the still unexplained changes of atmospheric CH4 over the past decade. Emissions and concentrations of CH4 are continuing to increase, making CH4 the second most important human-induced greenhouse gas after carbon dioxide. Two major difficulties in reducing uncertainties come from the large variety of diffusive CH4 sources that overlap geographically, and from the destruction of CH4 by the very short-lived hydroxyl radical (OH). To address these difficulties, we have established a consortium of multi-disciplinary scientists under the umbrella of the Global Carbon Project to synthesize and stimulate research on the methane cycle, and producing regular (˜ biennial) updates of the global methane budget. This consortium includes atmospheric physicists and chemists, biogeochemists of surface and marine emissions, and socio-economists who study anthropogenic emissions. Following Kirschke et al. (2013), we propose here the first version of a living review paper that integrates results of top-down studies (exploiting atmospheric observations within an atmospheric inverse-modelling framework) and bottom-up models, inventories and data-driven approaches (including process-based models for estimating land surface emissions and atmospheric chemistry, and inventories for anthropogenic emissions, data-driven extrapolations). For the 2003-2012 decade, global methane emissions are estimated by top-down inversions at 558 Tg CH4 yr-1, range 540-568. About 60 % of global emissions are anthropogenic (range 50-65 %). Since 2010, the bottom-up global emission inventories have been closer to methane emissions in the most carbon-intensive Representative Concentrations Pathway (RCP8.5) and higher than all other RCP scenarios

  13. Potential synergic effect between MOR and BEA zeolites in NOx SCR with methane: A dual bed design approach

    OpenAIRE

    Mendes, Acácio Nobre; Matynia, Alexis; Toullec, Alain; Capela, Sandra; Ribeiro, M.Filipa; Henriques, Carlos; Costa, Patrick Da

    2015-01-01

    International audience; The selective catalytic reduction of NOx with methane (NOx CH4-SCR) under lean conditions was investigated with catalysts based on two different zeolite structures (MOR and BEA) containing Pd and Ce. The catalytic performance for NO oxidation to NO2 reaction, considered an important first key step in the NOx CH4-SCR mechanism, was also assessed.Pd(0.3)Ce(2)-HBEA was found to be very active for NO oxidation but exhibits poor activity for NOx CH4-SCR. Conversely, Pd(0.3)...

  14. Understanding the contribution of non-carbon dioxide gases in deep mitigation scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Gernaat, David; Calvin, Katherine V.; Lucas, Paul; Luderer, Gunnar; Otto, Sander; Rao, Shilpa; Strefler, Jessica; Van Vuuren, Detlef

    2015-07-01

    The combined 2010 emissions of methane (CH4), nitrous oxide (N2O) and the fluorinated gasses (F-gas) account for about 20-30% of total emissions and about 30% of radiative forcing. At the moment, most studies looking at reaching ambitious climate targets project the emission of carbon dioxide (CO2) to be reduced to zero (or less) by the end of the century. As for non-CO2 gases, the mitigation potential seem to be more constrained, we find that by the end of the century in the current deep mitigation scenarios non-CO2 emissions could form the lion’s share of remaining greenhouse gas emissions. In order to support effective climate policy strategies, in this paper we provide a more in-depth look at the role of non-CO2¬ emission sources (CH4, N2O and F-gases) in achieving deep mitigation targets (radiative forcing target of 2.8 W/m2 in 2100). Specifically, we look at the sectorial mitigation potential and the remaining non-CO2 emissions. By including a set of different models, we provide some insights into the associated uncertainty. Most of the remaining methane emissions in 2100 in the climate mitigation scenario come from the livestock sector. Strong reductions are seen in the energy supply sector across all models. For N2O, less reduction potential is seen compared to methane and the sectoral differences are larger between the models. The paper shows that the assumptions on remaining non-CO2 emissions are critical for the feasibility of reaching ambitious climate targets and the associated costs.

  15. Mobile monitoring of fugitive methane emissions from natural gas consumer industries

    Science.gov (United States)

    Zhou, X.; Albertson, J. D.; Gaylord, A.; von Fischer, J.; Rudek, J.; Thoma, E. D.

    2015-12-01

    Natural gas is used as a feedstock for major industrial processes, such as ammonia and fertilizer production. However, fugitive methane emissions from many major end-use sectors of the natural gas supply chain have not been quantified yet. This presentation introduces new tools for estimating emission rates from mobile methane measurements, and examines results from recent field measurements conducted downwind of several industrial plants using a specialized vehicle equipped with fast response methane sensor. Using these data along with local meteorological data measured by a 3-D sonic anemometer, a Bayesian approach is applied to probabilistically infer methane emission rates based on a modified Gaussian dispersion model. Source rates are updated recursively with repeated traversals of the downwind methane plume when the vehicle was circling around the targeted facilities. Data from controlled tracer release experiments are presented and used to validate the approach. With access via public roads, this mobile monitoring method is able to quickly assess the emission strength of facilities along the sensor path. This work is developing the capacity for efficient regional coverage of potential methane emission rates in support of leak detection and mitigation efforts.

  16. Characterizations of purple non-sulfur bacteria isolated from paddy fields, and identification of strains with potential for plant growth-promotion, greenhouse gas mitigation and heavy metal bioremediation.

    Science.gov (United States)

    Sakpirom, Jakkapan; Kantachote, Duangporn; Nunkaew, Tomorn; Khan, Eakalak

    2017-04-01

    This study was aimed at selecting purple non-sulfur bacteria (PNSB) isolated from various paddy fields, including Cd- and Zn-contaminated paddy fields, based on their biofertilizer properties. Among 235 PNSB isolates, strain TN110 was most effective in plant growth-promoting substance (PGPS) production, releasing 3.2 mg/L of [Formula: see text] , 4.11 mg/L of 5-aminolevulinic acid (ALA) and 3.62 mg/L of indole-3-acetic acid (IAA), and reducing methane emission up to 80%. This strain had nifH, vnfG and anfG, which are the Mo, V and Fe nitrogenase genes encoded for key enzymes in nitrogen fixation under different conditions. This strain provided 84% and 55% removal of Cd and Zn, respectively. Another isolate, TN414, not only produced PGPS (1.30 mg/L of [Formula: see text] , 0.94 mg/L of ALA and 0.65 mg/L of IAA), but was also efficient in removing both Cd and Zn at 72% and 74%, respectively. Based on 16S rDNA sequencing, strain TN110 was identified as Rhodopseudomonas palustris, while strain TN414 was Rubrivivax gelatinosus. A combination of TN110 and TN414 could potentially provide a biofertilizer, which is a greener alternative to commercial/chemical fertilizers and an agent for bioremediation of heavy metals and greenhouse gas mitigation in paddy fields. Copyright © 2016 Institut Pasteur. All rights reserved.

  17. Reducing Open Cell Landfill Methane Emissions with a Bioactive Alternative Daily

    Energy Technology Data Exchange (ETDEWEB)

    Helene Hilger; James Oliver; Jean Bogner; David Jones

    2009-03-31

    Methane and carbon dioxide are formed in landfills as wastes degrade. Molecule-for-molecule, methane is about 20 times more potent than carbon dioxide at trapping heat in the earth's atmosphere, and thus, it is the methane emissions from landfills that are scrutinized. For example, if emissions composed of 60% methane and 40% carbon dioxide were changed to a mix that was 40% methane and 60% carbon dioxide, a 30% reduction in the landfill's global warming potential would result. A 10% methane, 90% carbon dioxide ratio will result in a 75% reduction in global warming potential compared to the baseline. Gas collection from a closed landfill can reduce emissions, and it is sometimes combined with a biocover, an engineered system where methane oxidizing bacteria living in a medium such as compost, convert landfill methane to carbon dioxide and water. Although methane oxidizing bacteria merely convert one greenhouse gas (methane) to another (carbon dioxide), this conversion can offer significant reductions in the overall greenhouse gas contribution, or global warming potential, associated with the landfill. What has not been addressed to date is the fact that methane can also escape from a landfill when the active cell is being filled with waste. Federal regulations require that newly deposited solid waste to be covered daily with a 6 in layer of soil or an alternative daily cover (ADC), such as a canvas tarp. The aim of this study was to assess the feasibility of immobilizing methane oxidizing bacteria into a tarp-like matrix that could be used for alternative daily cover at open landfill cells to prevent methane emissions. A unique method of isolating methanotrophs from landfill cover soil was used to create a liquid culture of mixed methanotrophs. A variety of prospective immobilization techniques were used to affix the bacteria in a tarp-like matrix. Both gel encapsulation of methanotrophs and gels with liquid cores containing methanotrophs were readily

  18. Potential Impacts of Paleohydrological Changes on Holocene Methane Fluxes in Boreal and Subarctic Peatlands, James Bay, Quebec, Canada

    Science.gov (United States)

    Garneau, M.; Ali, A.; Tremblay, L.; Pelletier, L.; Asnong, H.

    2008-12-01

    In boreal and subarctic region of the La Grande river watershed, James Bay, Quebec, Canada, peatlands cover closed to 15 % of the terrestrial surface. Multi proxy analysis results (plant macrofossils and Testate amoebae) from minerotrophic peatland have demonstrated important variations on the regional water table position since peat started to accumulate in the region ca 7400 cal BP. Macrofossil assemblages indicate that sites were first colonized by black spruce (Picea mariana Ait Muhl.) and Sphagnum spp which paludified with a regional rise of moisture at approx. 4500 BP. Drier conditions registered around 3900 cal BP induced a shift in vegetation and Testate amoeba assemblages for a relatively short period which was followed at approximately 3000 cal BP by an important increase in moisture. This shift in hydrological conditions involved drastic changes in the vegetation cover from Picea mariana and Sphagnum fuscum assemblages to sedges (Carex spp.) and wet Sphagnum species such as S. majus, S. subsecundum, S. pulchrum. This rise in the water table position could have induced enhance methane release to the atmosphere when considering the present-day methane fluxes/water table depth/vegetation cover relationship.

  19. Potential development of compressed bio-methane gas production from pig farms and elephant grass silage for transportation in Thailand.

    Science.gov (United States)

    Dussadee, Natthawud; Reansuwan, Kamoldara; Ramaraj, Rameshprabu

    2014-03-01

    This research project evaluated biogas production using anaerobic co-digestion of pig manure and elephant grass silage in large scale to delivered transportation directly for cars. Anaerobic co-digestion was estimated in three full-scale continuously stirred tank reactors (CSTRs) at 40°C. In the form of compressed bio-methane gas (CBG) production was 14,400m(3)/day (CH4 60-70%) amount of CBG was 9600m(3)/day. The procedure was enhanced by using molecular sieve, activated carbon for removal of moisture and CO2 membrane H2S and CO2 respectively. The results were demonstrated the amount of CO2, H2S gas was reduced along with CH4 was improved up to 90% by volume and compressed to 250bar tank pressure gauge to the fuel for cars. The CBG production, methane gas improvement and performance were evaluated before entering the delivered systems according to the energy standards. The production of CBG is advantageous to strengthen the Thailand biogas market.

  20. Sustainable biochar to mitigate global climate change

    Science.gov (United States)

    Woolf, Dominic; Amonette, James E.; Street-Perrott, F. Alayne; Lehmann, Johannes; Joseph, Stephen

    2010-01-01

    Production of biochar (the carbon (C)-rich solid formed by pyrolysis of biomass) and its storage in soils have been suggested as a means of abating climate change by sequestering carbon, while simultaneously providing energy and increasing crop yields. Substantial uncertainties exist, however, regarding the impact, capacity and sustainability of biochar at the global level. In this paper we estimate the maximum sustainable technical potential of biochar to mitigate climate change. Annual net emissions of carbon dioxide (CO2), methane and nitrous oxide could be reduced by a maximum of 1.8 Pg CO2-C equivalent (CO2-Ce) per year (12% of current anthropogenic CO2-Ce emissions; 1 Pg=1 Gt), and total net emissions over the course of a century by 130 Pg CO2-Ce, without endangering food security, habitat or soil conservation. Biochar has a larger climate-change mitigation potential than combustion of the same sustainably procured biomass for bioenergy, except when fertile soils are amended while coal is the fuel being offset. PMID:20975722

  1. Short-term variations of methane concentrations and methanotrophic activity in a coastal inlet (Eckernförde Bay, Germany)

    Science.gov (United States)

    Richner, Dominik; Niemann, Helge; Steinle, Lea; Schneider von Deimling, Jens; Urban, Peter; Hoffmann, Jasper; Schmidt, Mark; Treude, Tina; Lehmann, Moritz

    2016-04-01

    Large quantities of methane are produced in anoxic sediments of continental margins and may be liberated into the overlying water column and, potentially, into the atmosphere. However, a sequence of microbially mediated methane oxidation pathways in sediments and the water column mitigate the contribution of oceans to the atmospheric methane budget. Of particular importance are methanotrophic bacteria in the water column that mediate the aerobic oxidation of methane (MOx), and represent the final sink for methane before its release to the atmosphere where it acts as a potent greenhouse gas. However methane cycling in (aerobic) marine waters is not well constrained. Particularly little is known about spatiotemporal aspects of MOx activity and the underlying key physical, chemical and biological factors. Here we show results from our investigations on methane dynamics on very short time scales of hours to days in the Eckernförde Bay (E-Bay), a costal inlet of the Baltic Sea in northern Germany featuring seasonal bottom water hypoxia/anoxia. In autumn 2014, we observed highly spatiotemporal variations in water column methane contents and MOx activity: Anoxic bottom waters in a trough in the northern part of the bay contained extremely high methane concentrations of up to 800 nM, which sharply declined at the midwater redox interface (methane remained supersaturated with respect to the atmospheric equilibrium throughout the water column at all times). The methane decrease at the redox interface was related to highly active MOx communities consuming methane under microoxic conditions at rates of up 40 nM/d. About 12 hours later, the methane content and the extend of bottom water anoxia was much lower and MOx activity was highly reduced in the northern part but strongly elevated in the southern part of the bay. A few days later, bottom water anoxia, methane loading and MOx activity was partially re-established. In this contribution, we will discuss potential forcing

  2. Isotopic Evidence of a Sedimentary Carbon Source at the Endeavour Hydrothermal System, a Potential Site of Microbial Methane Oxidation

    Science.gov (United States)

    Proskurowski, G. K.; Lilley, M. D.; Brown, T. A.

    2002-12-01

    The hydrothermal systems on the Endeavour Segment of the Juan de Fuca Ridge have long been characterized as "bare rock hosted", as there is no sediment cover at Endeavour. However, chemical evidence in the form of anomalously high methane, ammonia and various trace metal concentrations reported in the last 10 years are consistent with a sediment source at Endeavour. Here we present a unique data set of stable and radiocarbon isotopic measurements made on CO2 from Endeavour hydrothermal vent fluids. When plotted against each other, a linear relationship between δ13CO2 and CO2 fraction modern values, suggests mixing of two CO2 sources. The data supports a mixing model between a -5.4\\permil, radiocarbon dead magmatic endmember, and a -17.8\\permil, 18,500 year old carbon source. The second endmember corresponds extremely well with stable isotopic measurements made on carbonate nodules from sediments at ODP drill sites on Middle Valley, a sedimented hydrothermal site 40km North of the Endeavour Segment. These sediments were emplaced during turbidite flows in the late Pleistocene, nominally 20,000 years ago. The mixing model suggests that about 20% of the CO2 found in Endeavour hydrothermal vent fluids is from this sedimentary endmember. We propose that the observed sedimentary signal is incorporated as heated hydrothermal fluids migrate upwards beneath the ridge axis through a zone of buried sediments. An alternative explanation is that there is a hydrologic link between Middle Valley and Endeavour, and that the sedimentary signal is imported from observed sediments at Middle Valley. Sediments provide labile sources of carbon that may be incorporated into microbial metabolic pathways. Sediments at Middle Valley exhibit strongly depleted δ13CO2 values (between -27 and -44\\permil) suggesting microbial fractionation, most likely anaerobic methane oxidation. While microbial methane oxidation is likely an active process in sediments at Middle Valley, isotopic evidence

  3. The social cost of methane: theory and applications.

    Science.gov (United States)

    Shindell, D T; Fuglestvedt, J S; Collins, W J

    2017-08-24

    Methane emissions contribute to global warming, damage public health and reduce the yield of agricultural and forest ecosystems. Quantifying these damages to the planetary commons by calculating the social cost of methane (SCM) facilitates more comprehensive cost-benefit analyses of methane emissions control measures and is the first step to potentially incorporating them into the marketplace. Use of a broad measure of social welfare is also an attractive alternative or supplement to emission metrics focused on a temperature target in a given year as it incentivizes action to provide benefits over a broader range of impacts and timescales. Calculating the SCM using consistent temporal treatment of physical and economic processes and incorporating climate- and air quality-related impacts, we find large SCM values, e.g. ∼$2400 per ton and ∼$3600 per ton with 5% and 3% discount rates respectively. These values are ∼100 and 50 times greater than corresponding social costs for carbon dioxide. Our results suggest that ∼110 of 140 Mt of identified methane abatement via scaling up existing technology and policy options provide societal benefits that outweigh implementation costs. Within the energy sector, renewables compare far better against use of natural gas in electricity generation when incorporating these social costs for methane. In the agricultural sector, changes in livestock management practices, promoting healthy diets including reduced beef and dairy consumption, and reductions in food waste have been promoted as ways to mitigate emissions, and these are shown here to indeed have the potential to provide large societal benefits (∼$50-150 billion per year). Examining recent trends in methane and carbon dioxide, we find that increases in methane emissions may have offset much of the societal benefits from a slowdown in the growth rate of carbon dioxide emissions. The results indicate that efforts to reduce methane emissions via policies spanning a wide

  4. Coal Bed Methane Primer

    Energy Technology Data Exchange (ETDEWEB)

    Dan Arthur; Bruce Langhus; Jon Seekins

    2005-05-25

    During the second half of the 1990's Coal Bed Methane (CBM) production increased dramatically nationwide to represent a significant new source of income and natural gas for many independent and established producers. Matching these soaring production rates during this period was a heightened public awareness of environmental concerns. These concerns left unexplained and under-addressed have created a significant growth in public involvement generating literally thousands of unfocused project comments for various regional NEPA efforts resulting in the delayed development of public and fee lands. The accelerating interest in CBM development coupled to the growth in public involvement has prompted the conceptualization of this project for the development of a CBM Primer. The Primer is designed to serve as a summary document, which introduces and encapsulates information pertinent to the development of Coal Bed Methane (CBM), including focused discussions of coal deposits, methane as a natural formed gas, split mineral estates, development techniques, operational issues, producing methods, applicable regulatory frameworks, land and resource management, mitigation measures, preparation of project plans, data availability, Indian Trust issues and relevant environmental technologies. An important aspect of gaining access to federal, state, tribal, or fee lands involves education of a broad array of stakeholders, including land and mineral owners, regulators, conservationists, tribal governments, special interest groups, and numerous others that could be impacted by the development of coal bed methane. Perhaps the most crucial aspect of successfully developing CBM resources is stakeholder education. Currently, an inconsistent picture of CBM exists. There is a significant lack of understanding on the parts of nearly all stakeholders, including industry, government, special interest groups, and land owners. It is envisioned the Primer would being used by a variety of

  5. Ab initio calculation of the interaction potentials of helium, neon, and methane as well as theoretical studies on their thermophysical properties and those of water vapor; Ab initio-Berechnung der Wechselwirkungspotentiale von Helium, Neon und Methan sowie theoretische Untersuchungen zu ihren thermophysikalischen Eigenschaften und denen von Wasserdampf

    Energy Technology Data Exchange (ETDEWEB)

    Hellmann, Robert

    2009-06-16

    Thermophysical properties of the pure gases helium, neon, methane and water vapor were calculated for low densities over wide temperature ranges. Statistical thermodynamics was used for the determination of the pressure virial coefficients. The kinetic theory of gases was utilized for the calculation of the transport and relaxation properties. So far kinetic theory was limited to linear molecules and has now been extended to molecules of arbitrary geometry to enable calculations on methane and water vapor. The interaction potentials, which are needed for all computations, were determined for helium, neon and methane from the supermolecular approach using quantum chemical ab initio methods. For water the interaction potentials were taken from the literature. The calculated values of the thermophysical properties for the four gases show very good agreement with the best experimental data. At very low and very high temperatures the theoretical values are more accurate than experimental data. (orig.)

  6. Ocean-Based Alkalinity Enhancement: Mitigation Potential, Side Effects and the Fate of Added Alkalinity Assessed in an Earth System Model

    Science.gov (United States)

    Gonzalez, M. F.; Ilyina, T.

    2014-12-01

    Artificial ocean alkalinization (AOA) has been proposed as a mean to mitigate climate change and ocean acidification. Whilst the mitigation potential of this geo-engineering technology may sound promising, it poses environmental risks. Within the Priority Program "Climate Engineering" of the German Science Foundation (DFG), we investigate the mitigation potential of AOA to reduce atmospheric CO2 and counteract the consequences of ocean acidification. We are particularly interested in the residence time of the added alkalinity at the ocean surface because it must stay in the upper ocean in order to increase the oceanic CO2 uptake. The mitigation potential, risks and the unintended consequences of this geo-engineering method are also exhaustively studied. These questions are tackled through the analysis of different alkalinity enhancement scenarios in the state-of-the-art Earth system model of the Max Planck Institute for Meteorology (MPI-ESM) in a configuration based on the fifth phase of the Coupled Model Intercomparison Project (CMIP5). Model scenarios are designed so that AOA is performed to keep the atmospheric CO2 concentrations similar to values of the stabilization scenario RCP4.5, while fossil fuel CO2 emissions follow the pathway of the high-CO2 scenario RCP8.5. Alkalinity is added globally into the upper 12 meters of the ocean in different seasons and years. We found that on the time scale of relevance (i.e. from years to decades), season and location are key aspects to take into account in the implementation of AOA. This is because of inhomogeneous vertical mixing of added alkalinity due to the mixed layer depth which is established by the season. We also show that the rate of addition greatly determines impact and outcome of this geo-engineering method. Changes driven by the implementation of this method in the ocean biogeochemistry are also discussed. For instance, the associated changes in the carbon cycle, marine oxygen levels, saturation state of

  7. Design and test of an artificial reference cow to simulate methane release through exhalation

    NARCIS (Netherlands)

    Wu, Liansun; Groot Koerkamp, P.W.G.; Ogink, N.W.M.

    2015-01-01

    To mitigate methane emission from dairy cows, a technique is needed to evaluate individual methane emission from a large number of cows under practical conditions in barns. For developing such a measurement technique, a known reference source that can simulate cow exhalation of methane would be a

  8. Design and test of an artificial reference cow to simulate methane release through exhalation

    NARCIS (Netherlands)

    Wu, Liansun; Groot Koerkamp, P.W.G.; Ogink, N.W.M.

    2015-01-01

    To mitigate methane emission from dairy cows, a technique is needed to evaluate individual methane emission from a large number of cows under practical conditions in barns. For developing such a measurement technique, a known reference source that can simulate cow exhalation of methane would be a

  9. Fluorescence analysis of NOM degradation by photocatalytic oxidation and its potential to mitigate membrane fouling in drinking water treatment.

    Science.gov (United States)

    Nerger, Bryan A; Peiris, Ramila H; Moresoli, Christine

    2015-10-01

    This study examined the photocatalytic oxidation of natural organic matter (NOM) as a method to mitigate membrane fouling in drinking water treatment. ZnO and TiO2 photocatalysts were tested in concentrations ranging from 0.05 g L(-1) to 0.5 g L(-1). Fluorescence peaks were used as the primary method to characterize the degradation of three specific NOM components - fulvic acid-like humic substances, humic acid-like humic substances, and protein-like substances during photocatalytic oxidation. Fluorescence peaks and Liquid Chromatography-Organic Carbon Detection (LC-OCD) analysis indicated that higher NOM degradation was obtained by photocatalytic oxidation with ZnO than with TiO2. Treatment of the feed water by ZnO photocatalytic oxidation was successful in reducing considerably the extent of hydraulically reversible and irreversible membrane fouling during ultrafiltration (UF) compared to feed water treatment with TiO2. Fouling during UF of water subjected to photocatalytic oxidation appeared to be caused by low molecular weight constituents of NOM generated during photocatalytic oxidation.

  10. Spatial variability of diploptene δ13C values in thermokarst lakes: the potential to analyse the complexity of lacustrine methane cycling

    Directory of Open Access Journals (Sweden)

    K. L. Davies

    2015-08-01

    Full Text Available Cryospheric changes in northern high latitudes are linked to significant greenhouse gas flux to the atmosphere, including methane release that originates from organic matter decomposition in thermokarst lakes. The connections between methane production in sediments, transport pathways and oxidation are not well understood and this has implications for any attempts to reconstruct methane production from sedimentary archives. We assessed methane oxidation as represented by methane oxidising bacteria across the surface sediments of two interior Alaska thermokarst lakes in relation to methane emissions via ebullition (bubbling. The bacterial biomarker diploptene was present and had low δ13C values (lower than −38 ‰ in all sediments analysed, suggesting methane oxidation was widespread. The most δ13C-depleted diploptene was found in the area of highest methane ebullition emissions in Ace Lake (δ13C diplotene values between −68.2 and −50.1 ‰, suggesting a positive link between methane production, oxidation, and emission in this area. In contrast, significantly less depleted diploptene δ13C values (between −42.9 and −38.8 ‰ were found in the area of highest methane ebullition emissions in Smith Lake. Lower δ13C values of diploptene were found in the central area of Smith Lake (between −56.8 and −46.9 ‰, where methane ebullition rates are low but methane diffusion appears high. Using δ13C-diplotene as a proxy for methane oxidation activity, we suggest the observed differences in methane oxidation levels among sites within the two lakes could be linked to differences in source area of methane production (e.g. age and type of organic carbon and bathymetry as it relates to varying oxycline depths and changing pressure gradients. As a result, methane oxidation is highly lake-dependent. The diploptene δ13C values also highlight strong within-lake variability, implying that single-value, down-core records of hopanoid isotopic

  11. Retrieval of methane source strengths in Europe using a simple modeling approach to assess the potential of space-borne lidar observations

    Directory of Open Access Journals (Sweden)

    C. Weaver

    2013-07-01

    Full Text Available We investigate the sensitivity of future space-borne lidar measurements to changes in surface methane emissions. We use surface methane observations from nine European ground stations, and a Lagrangian transport model to obtain surface methane emissions for 2010. Our inversion shows the strongest emissions from the Netherlands, the coalmines in Upper Silesia Poland, and wetlands in southern Finland. Our simulated methane surface concentration captures at least half of the daily variability in the observations, suggesting that the transport model is correctly simulating the regional transport pathways over Europe. With this tool we can perturb the surface fluxes and see the resulting changes in the simulated column methane measurements. For example, we show that future lidar instruments can detect a 50% reduction in methane emissions from the Netherlands and Germany, but only after averaging measurements on a monthly time scale.

  12. The potential of coordinated reservoir operation for flood mitigation in large basins - A case study on the Bavarian Danube using coupled hydrological-hydrodynamic models

    Science.gov (United States)

    Seibert, S. P.; Skublics, D.; Ehret, U.

    2014-09-01

    The coordinated operation of reservoirs in large-scale river basins has great potential to improve flood mitigation. However, this requires large scale hydrological models to translate the effect of reservoir operation to downstream points of interest, in a quality sufficient for the iterative development of optimized operation strategies. And, of course, it requires reservoirs large enough to make a noticeable impact. In this paper, we present and discuss several methods dealing with these prerequisites for reservoir operation using the example of three major floods in the Bavarian Danube basin (45,000 km2) and nine reservoirs therein: We start by presenting an approach for multi-criteria evaluation of model performance during floods, including aspects of local sensitivity to simulation quality. Then we investigate the potential of joint hydrologic-2d-hydrodynamic modeling to improve model performance. Based on this, we evaluate upper limits of reservoir impact under idealized conditions (perfect knowledge of future rainfall) with two methods: Detailed simulations and statistical analysis of the reservoirs' specific retention volume. Finally, we investigate to what degree reservoir operation strategies optimized for local (downstream vicinity to the reservoir) and regional (at the Danube) points of interest are compatible. With respect to model evaluation, we found that the consideration of local sensitivities to simulation quality added valuable information not included in the other evaluation criteria (Nash-Sutcliffe efficiency and Peak timing). With respect to the second question, adding hydrodynamic models to the model chain did, contrary to our expectations, not improve simulations, despite the fact that under idealized conditions (using observed instead of simulated lateral inflow) the hydrodynamic models clearly outperformed the routing schemes of the hydrological models. Apparently, the advantages of hydrodynamic models could not be fully exploited when

  13. The use of reflective and permeable pavements as a potential practice for heat island mitigation and stormwater management

    Science.gov (United States)

    Li, H.; Harvey, J. T.; Holland, T. J.; Kayhanian, M.

    2013-03-01

    To help address the built environmental issues of both heat island and stormwater runoff, strategies that make pavements cooler and permeable have been investigated through measurements and modeling of a set of pavement test sections. The investigation included the hydraulic and thermal performance of the pavements. The permeability results showed that permeable interlocking concrete pavers have the highest permeability (or infiltration rate, ˜0.5 cm s-1). The two permeable asphalt pavements showed the lowest permeability, but still had an infiltration rate of ˜0.1 cm s-1, which is adequate to drain rainwater without generating surface runoff during most typical rain events in central California. An increase in albedo can significantly reduce the daytime high surface temperature in summer. Permeable pavements under wet conditions could give lower surface temperatures than impermeable pavements. The cooling effect highly depends on the availability of moisture near the surface layer and the evaporation rate. The peak cooling effect of watering for the test sections was approximately 15-35 °C on the pavement surface temperature in the early afternoon during summer in central California. The evaporative cooling effect on the pavement surface temperature at 4:00 pm on the third day (25 h after watering) was still 2-7 °C lower compared to that on the second day, without considering the higher air temperature on the third day. A separate and related simulation study performed by UCPRC showed that full depth permeable pavements, if designed properly, can carry both light-duty traffic and certain heavy-duty vehicles while retaining the runoff volume captured from an average California storm event. These preliminarily results indicated the technical feasibility of combined reflective and permeable pavements for addressing the built environment issues related to both heat island mitigation and stormwater runoff management.

  14. Methane emission from sub-sea permafrost in the East Siberian Arctic shelf: model-based evaluation of potential impact on global climate

    Science.gov (United States)

    Anisimov, O. A.; Lavrov, S. A.; Borzenkova, I. I.

    2011-12-01

    Several recent publications suggest that the observed high concentration of methane over the East Siberian Shelf (ESS) may be attributed to thawing and increased gas permeability (through taliks) of the sub-sea permafrost. Methane is released from unstable gas hydrates and propagates through newly formed taliks in the bottom sediments to the water and further to the atmosphere. Under sustained warming in the following decades it may have potentially dramatic effect on global climate. In this study we examine this hypothesis using comprehensive modelling approach. Direct observations indicate that since the mid-1980s bottom waters over the ESS warmed by ca. 2.1°C. We used the model to examine whether such changes may have caused substantial degradation of methane bearing sub-sea permafrost and CH4 supersaturation of the ESS sea waters. The model is based on the heat transfer equation and explicitly accounts for the effect of salt diffusion in the bottom sediments by coupling the thermal and mass fluxes. We forced the model by the prescribed seasonal bottom water temperature and salinity to calculate changes in the thermal state of permafrost after the inundation of the ESS, and to predict the changes in the following 1000 years. We used a climate scenario suggesting that at the time of inundation (ca 8 Ky BP) the top sediment layer warmed by ca. 12 °C from -13.5 °C (mean annual air temperature) to -1.5 °C (bottom water temperature). Afterwards temperature remained unchanged until 1985. Since then in accord with modern observations we imposed 0.09°C/year trend until 2100, and prescribed temperature to constant value of 11.5 °C afterwards. The rate of temperature change in the 21st century in this highly schematic scenario by far exceeds all IPCC projections. We did it intentionally to explore the most extreme pathway for potential sub-see permafrost degradation underneath the ESS. Model results indicated ca 1 m deepening of the upper sub-sea permafrost boundary

  15. The Nanchang Communication about the potential for implementation of conservation practices for climate change mitigation and adaptation to achieve food security in the 21st century

    Directory of Open Access Journals (Sweden)

    Jorge A. Delgado

    2016-06-01

    Full Text Available There is a large number of peer-reviewed publications reporting that a changing climate is one of the biggest challenges humanity will have during the 21st century. With population growth and the need to significantly increase agricultural production per unit of area during the 21st century, a changing climate will put additional stress on soil resources. Soil and water conservation will be key for the future of humanity. Professional societies in the area of agriculture and soil and water conservation have recognized the importance that soil resources will have for humanity during this century and have made calls for implementation of worldwide soil and water conservation. For example, in 2010 the Soil and Water Conservation Society (SWCS invited a group of scientists to review the literature about the potential to use conservation practices for climate change adaptation and mitigation. The Delgado et al. (2011 paper was used by the SWCS to develop and adopt a position statement about the importance of using soil and water conservation practices to mitigate and adapt to climate change. The International Soil Conservation Organization (ISCO invited the lead author to present the paper as a keynote presentation at the ISCO 2013 conference. The European Society of Soil Conservation (ESSC published a short communication about this paper in one of their newsletters in 2014. The World Association of Soil and Water Conservation (WASWAC also invited the lead author to present a keynote presentation on this topic at the 2015 WASWAC annual meeting in Nanchang. This paper (the Nanchang Communication is a summary of the Delgado et al. (2011 paper that was used by the SWCS to develop the SWCS position statement related to soil and water conservation and climate change. The Nanchang Communication (this paper was used by WASWAC to develop a position statement about the immediate need for implementation of conservation practices for mitigation of and

  16. Assessment of Emerging Regional Air Quality (AQ) and Greenhouse Gas (GHG) Impacts and Potential Mitigation Strategies in U.S. Energy Sectors

    Science.gov (United States)

    Kinnon, Michael Mac

    The current domestic reliance on high-emitting fossil fuels for energy needs is the key driver of U.S. greenhouse gas (GHG) and pollutant emissions driving both climate change and regional air quality (AQ) concerns. Moving forward, emission sources in U.S. energy sectors will be subjected to changes driven by numerous phenomena, including technology evolution, environmental impacts, sustainability goals, and socioeconomic factors. This evolution will directly affect emissions source-related impacts on regional AQ that effective emissions control strategies must account for, including relative source contributions. Though previous studies have evaluated the emissions and AQ impacts of different sectors, technologies and fuels, most previous studies have assessed emissions impacts only without using advanced atmospheric models to accurately account for both spatial and temporal emissions perturbations and atmospheric chemistry and transport. In addition, few previous studies have considered the integration of multiple technologies and fuels in different U.S. regions.. Finally, most studies do not project emissions several decades into the future to assess what sources should be targeted with priority over time. These aspects are critical for understanding how both emissions sources and potential mitigation strategies impact the formation and fate of primary and secondary pollutants, including ground-level ozone and particulate matter concentrations. Therefore, this work utilizes a set of modeling tools to project and then to spatially and temporally resolve emissions as input into a 3-D Eulerian AQ model to assess how sources of emissions contribute to future atmospheric pollutant burdens. Further, analyses of the potential impacts of alternative energy strategies contained in potential mitigation strategies are conducted for priority targets to develop an understanding of how to maximize AQ benefits and avoid unforeseen deleterious tradeoffs between GHG reduction

  17. Detecting Methane Emission Sources in California: a Case-Study of Scientist/Decision-Maker Interactions

    Science.gov (United States)

    Hopkins, F. M.; Duren, R. M.; Miller, C. E.; Aubrey, A. D.; Falk, M.; Kuwayama, T.; Hinojosa, L.

    2015-12-01

    Reducing anthropogenic methane emissions is a high priority for the state of California as a strategy to meet near-term greenhouse gas emissions targets. However, implementation of an effective, cost-efficient methane mitigation plan requires local-to-regional scale information on methane sources, and cooperation of diverse stakeholders. We hypothesize that methane "super-emitters," large point sources thought to contribute disproportionately to anthropogenic methane emissions, are logical mitigation targets. We outline a tiered observing strategy involving satellite, aircraft, and surface observations to identify these super-emitters and their contribution to regional methane emissions. We demonstrate this approach with field studies of agricultural and oil and gas sources in California's San Joaquin Valley with cooperation a multi-stakeholder team. This partnership between researchers, regulators, and methane emitting industry took advantage of data sharing, site access, and complementary measurement approaches to identify appropriate methane mitigation targets. This experience suggests that collaborative partnerships that leverage multiple observational methods will be required for identifying methane mitigation targets and crafting regionally appropriate methane mitigation policy.

  18. Direct Aromaization of Methane

    Energy Technology Data Exchange (ETDEWEB)

    George Marcelin

    1997-01-15

    The thermal decomposition of methane offers significant potential as a means of producing higher unsaturated and aromatic hydrocarbons when the extent of reaction is limited. Work in the literature previous to this project had shown that cooling the product and reacting gases as the reaction proceeds would significantly reduce or eliminate the formation of solid carbon or heavier (Clo+) materials. This project studied the effect and optimization of the quenching process as a means of increasing the amount of value added products during the pyrolysis of methane. A reactor was designed to rapidly quench the free-radical combustion reaction so as to maximize the yield of aromatics. The use of free-radical generators and catalysts were studied as a means of lowering the reaction temperature. A lower reaction temperature would have the benefits of more rapid quenching as well as a more feasible commercial process due to savings realized in energy and material of construction costs. It was the goal of the project to identify promising routes from methane to higher hydrocarbons based on the pyrolysis of methane.

  19. Microbial mitigation of greenhouse gas emissions from landfill cover soils

    Science.gov (United States)

    Lee, Sung-Woo

    Landfills are one of the major sources of methane (CH4), a potent greenhouse gas with a global warming potential (GWP) ˜23 times higher than that of carbon dioxide (CO2). Although some effective strategies have been formulated to prevent methane emissions from large landfills, many landfills allow methane to be freely emitted to the atmosphere. In such situations, it is often proposed to stimulate methanotrophs, a group of bacteria that consume methane, in the cover soil to prevent fugitive methane emissions. Several factors, however, must be addressed to make such a biogenic removal mechanism effective. First, methanotrophic activity can be inhibited by nonmethane organic compounds (NMOCs) that are commonly found in landfill soil gas. Second, although methanotrophs can be easily stimulated with the addition of nitrogenous fertilizers, biogenic production of nitrous oxide with a GWP ˜296 times higher than that of carbon dioxide, is also stimulated. To consider these issues, two general areas of research were performed. First, a dimensionless number was developed based on Michaelis-Menten kinetics that describes the effects of the presence of multiple NMOCs on methanotrophic growth and survival. This model was validated via experimental measurements of methanotrophic growth in the presence of varying amounts of NMOCs. Second, the effects of nutrient amendments on methane oxidation and nitrous oxide production were examined by constructing soil microcosms using landfill cover soils. Here, it was shown that the addition of ammonium in the presence of phenylacetylene stimulated methane oxidation but inhibited nitrous oxide production. Furthermore, to understand the methanotrophic community structure and activity in response to these amendments, DNA microarray and transcript analyses were performed. The results indicated the predominance of Type II methanotrophs but that Type I methanotrophs responded more significantly to these amendments. Also, substantial activity

  20. 生活垃圾填埋场甲烷自然减排的新途径——厌氧与好氧的共氧化作用%New Way for Natural Mitigation of Methane in Domestic Waste Landfill Sites: Co-oxidation of Anaerobic and Aerobic Oxidation

    Institute of Scientific and Technical Information of China (English)

    周海燕; 韩丹

    2011-01-01

    通过证实生活垃圾填埋场中甲烷厌氧氧化与好氧氧化的共存,提出了甲烷自然减排的新途径.分别选取暴雨过后垃圾填埋表层30~60 cm的覆土、1.5 m以下的垃圾以及底层矿化垃圾做硫酸盐还原菌阳性反应实验,结果表明:生活垃圾填埋体不同填埋层都存在不同数量级的硫酸盐还原菌,且底层矿化垃圾中的硫酸盐还原菌的数量最多,表层覆土中最少.颗粒大小比例为50%:50%的垃圾样品表现出最佳的甲烷好氧与厌氧氧化效果,且厌氧氧化在共氧化作用中的比例达到20%以上.含水率为25%时,矿化垃圾中微生物活性最大,好氧与厌氧氧化甲烷速率均达到最大;当含水率接近70%时,甲烷厌氧氧化的贡献率可达30%以上.外源甲烷的补充可以驯化甲烷氧化微生物,其中甲烷好氧氧化时间最大可缩短50%;而甲烷通入量超过2 mL后,甲烷好氧与厌氧氧化均受到抑制.%A new way for natural mitigation of methane was put forward by authenticating co-oxidation of anaerobic and aerobic oxidation of methane in domestic waste landfill sites. The soil at 30-60 cm, the waste below 1.5 m from the surface, and the aged waste at the bottom, were selected for the experiments of sulfate-reducing bacteria positive reaction. The results showed that sulfate-reducing bacteria nearly existed in all landfill layers of waste landfill bodies, and aged waste at the bottom contained most, the surface soil contained least. Waste samples with 50%: 50% of coarse and fine particle size proportion showed the best methane oxidation effect of aerobic and anaerobic oxidation, and anaerobic oxidation accounted for above 20%. Microbial activity in aged waste and its methane co-oxidation rate both reached the maximum value as moisture content was 25%. Anaerobic oxidation rate could reach more than 30% as moisture content was close to 70%. Supplement of exogenous methane could culture methane-oxidizing bacteria

  1. Methane adsorption on activated carbon

    OpenAIRE

    Perl, Andras; Koopman, Folkert; Jansen, Peter; Rooij, Marietta de; Gemert, Wim van

    2014-01-01

    Methane storage in adsorbed form is a promising way to effectively and safely store fuel for vehicular transportation or for any other potential application. In a solid adsorbent, nanometer wide pores can trap methane by van der Waals forces as high density fluid at low pressure and room temperature. This provides the suitable technology to replace bulky and expensive cylindrical compressed natural gas tanks. Activated carbons with large surface area and high porosity are particularly suitabl...

  2. The oxidative coupling of methane

    Energy Technology Data Exchange (ETDEWEB)

    Helton, T.; Anthony, R.G.; Gadalla, A.M. (Texas A and M Univ., College Park, TX (US))

    1988-01-01

    In this paper the spinel phase of cobalt oxide is evaluated as a potential coupling catalyst for converting methane to C/sub 2/+ hydrocarbons. Thermodynamic calculations indicate that the Gibbs free energies for forming higher hydrocarbons using the spinel form of cobalt oxide are similar to the free energies obtained for manganese (III) oxide. The oxidative coupling of methane was performed in an oxidation-reduction cycle.

  3. The <