WorldWideScience

Sample records for cell landfill methane

  1. Bio-tarp alternative daily cover prototypes for methane oxidation atop open landfill cells.

    Science.gov (United States)

    Adams, Bryn L; Besnard, Fabien; Bogner, Jean; Hilger, Helene

    2011-05-01

    Final landfill covers are highly engineered to prevent methane release into the atmosphere. However, methane production begins soon after waste placement and is an unaddressed source of emissions. The methane oxidation capacity of methanotrophs embedded in a "bio-tarp" was investigated as a means to mitigate methane release from open landfill cells. The bio-tarp would also serve as an alternative daily cover during routine landfill operation. Evaluations of nine synthetic geotextiles identified two that would likely be suitable bio-tarp components. Pilot tarp prototypes were tested in continuous flow systems simulating landfill gas conditions. Multilayered bio-tarp prototypes consisting of alternating layers of the two geotextiles were found to remove 16% of the methane flowing through the bio-tarp. The addition of landfill cover soil, compost, or shale amendments to the bio-tarp increased the methane removal up to 32%. With evidence of methane removal in a laboratory bioreactor, prototypes were evaluated at a local landfill using flux chambers installed atop intermediate cover at a landfill. The multilayered bio-tarp and amended bio-tarp configurations were all found to decrease landfill methane flux; however, the performance efficacy of bio-tarps was not significantly different from controls without methanotrophs. Because highly variable methane fluxes at the field site likely confounded the test results, repeat field testing is recommended under more controlled flux conditions.

  2. 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

  3. Quantification of methane emissions from danish landfills

    DEFF Research Database (Denmark)

    Scheutz, Charlotte; Mønster, Jacob; Kjeldsen, Peter

    2013-01-01

    Whole-landfill methane emission was quantified using a tracer technique that combines controlled tracer gas release from the landfill with time-resolved concentration measurements downwind of the landfill using a mobile high-resolution analytical instrument. Methane emissions from 13 Danish...... landfills varied between 2.6 and 60.8 kg CH4 h–1. The highest methane emission was measured at the largest (in terms of disposed waste amounts) of the 13 landfills, whereas the lowest methane emissions (2.6-6.1 kgCH4 h–1) were measured at the older and smaller landfills. At two of the sites, which had gas...... collection, emission measurements showed that the gas collection systems only collected between 30-50% of the methane produced (assuming that the produced methane equalled the sum of the emitted methane and the collected methane). Significant methane emissions were observed from disposed shredder waste...

  4. LANDFILL OPERATION FOR CARBON SEQUESTRATION AND MAXIMUM METHANE EMISSION CONTROL

    Energy Technology Data Exchange (ETDEWEB)

    Don Augenstein; Ramin Yazdani; Rick Moore; Michelle Byars; Jeff Kieffer; Professor Morton Barlaz; Rinav Mehta

    2000-02-26

    Controlled landfilling is an approach to manage solid waste landfills, so as to rapidly complete methane generation, while maximizing gas capture and minimizing the usual emissions of methane to the atmosphere. With controlled landfilling, methane generation is accelerated to more rapid and earlier completion to full potential by improving conditions (principally moisture, but also temperature) to optimize biological processes occurring within the landfill. Gas is contained through use of surface membrane cover. Gas is captured via porous layers, under the cover, operated at slight vacuum. A field demonstration project has been ongoing under NETL sponsorship for the past several years near Davis, CA. Results have been extremely encouraging. Two major benefits of the technology are reduction of landfill methane emissions to minuscule levels, and the recovery of greater amounts of landfill methane energy in much shorter times, more predictably, than with conventional landfill practice. With the large amount of US landfill methane generated, and greenhouse potency of methane, better landfill methane control can play a substantial role both in reduction of US greenhouse gas emissions and in US renewable energy. The work described in this report, to demonstrate and advance this technology, has used two demonstration-scale cells of size (8000 metric tons [tonnes]), sufficient to replicate many heat and compaction characteristics of larger ''full-scale'' landfills. An enhanced demonstration cell has received moisture supplementation to field capacity. This is the maximum moisture waste can hold while still limiting liquid drainage rate to minimal and safely manageable levels. The enhanced landfill module was compared to a parallel control landfill module receiving no moisture additions. Gas recovery has continued for a period of over 4 years. It is quite encouraging that the enhanced cell methane recovery has been close to 10-fold that experienced with

  5. Assessment of methane generation, oxidation, and emission in a subtropical landfill test cell.

    Science.gov (United States)

    Moreira, João M L; Candiani, Giovano

    2016-08-01

    This paper presents results of a methane balance assessment in a test cell built in a region with a subtropical climate near São Paulo, Brazil. Measurements and calculations were carried out to obtain the total methane emission to the atmosphere, the methane oxidation rate in the cover, and the total methane generation rate in the test cell. The oxidation rate was obtained through a calculation scheme based on a vertical one-dimensional methane transport in the cover region. The measured maximum and mean methane fluxes to the atmosphere were 124.4 and 15.87 g m(-2) d(-1), respectively. The total methane generation rate obtained for the test cell was 0.0380 ± 0.0075 mol s(-1). The results yielded that 69 % of the emitted methane occurred through the central well and 31 % through the cover interface with the atmosphere. The evaluations of the methane oxidation fraction for localized conditions in the lateral embankment of the test cell yielded 0.36 ± 0.11, while for the whole test cell yielded 0.15 ± 0.10. These results conciliate localized and overall evaluations reported in the literature. The specific methane generation rate obtained for the municipal solid waste with an age of 410 days was 317 ± 62 mol year(-1) ton(-1). This result from the subtropical São Paulo region is lower than reported figures for tropical climates and higher than reported figures for temperate climates.

  6. Methane elimination methods on landfills

    OpenAIRE

    Ponikvar, Martin

    2008-01-01

    Increase in substance and energy exploitation from waste which reduces the greenhouse gas emissions are one of the main goals of environmental protection. Slovenian legislation defines that in case captured landfill gas cannot be used for energy acquisition, incineration on the landfill itself or some other equivalent procedure must be used to prevent gas emissions into the air. The graduation thesis is based on existing municipal landfill Volče where suitable gas elimination is yet to be arr...

  7. LANDFILL GAS PRETREATMENT FOR FUEL CELL APPLICATIONS

    Science.gov (United States)

    The paper discusses the U.S. EPA's program, underway at International Fuel Cells Corporation, to demonstrate landfill methane control and the fuel cell energy recovery concept. In this program, two critical issues are being addressed: (1) a landfill gas cleanup method that would ...

  8. Methane production in simulated hybrid bioreactor landfill.

    Science.gov (United States)

    Xu, Qiyong; Jin, Xiao; Ma, Zeyu; Tao, Huchun; Ko, Jae Hac

    2014-09-01

    The aim of this work was to study a hybrid bioreactor landfill technology for landfill methane production from municipal solid waste. Two laboratory-scale columns were operated for about ten months to simulate an anaerobic and a hybrid landfill bioreactor, respectively. Leachate was recirculated into each column but aeration was conducted in the hybrid bioreactor during the first stage. Results showed that leachate pH in the anaerobic bioreactor maintained below 6.5, while in the hybrid bioreactor quickly increased from 5.6 to 7.0 due to the aeration. The temporary aeration resulted in lowering COD and BOD5 in the leachate. The volume of methane collected from the hybrid bioreactor was 400 times greater than that of the anaerobic bioreactor. Also, the methane production rate of the hybrid bioreactor was improved within a short period of time. After about 10 months' operation, the total methane production in the hybrid bioreactor was 212 L (16 L/kgwaste).

  9. LANDFILL OPERATION FOR CARBON SEQUESTRATION AND MAXIMUM METHANE EMISSION CONTROL

    Energy Technology Data Exchange (ETDEWEB)

    Don Augenstein

    2001-02-01

    The work described in this report, to demonstrate and advance this technology, has used two demonstration-scale cells of size (8000 metric tons [tonnes]), sufficient to replicate many heat and compaction characteristics of larger ''full-scale'' landfills. An enhanced demonstration cell has received moisture supplementation to field capacity. This is the maximum moisture waste can hold while still limiting liquid drainage rate to minimal and safely manageable levels. The enhanced landfill module was compared to a parallel control landfill module receiving no moisture additions. Gas recovery has continued for a period of over 4 years. It is quite encouraging that the enhanced cell methane recovery has been close to 10-fold that experienced with conventional landfills. This is the highest methane recovery rate per unit waste, and thus progress toward stabilization, documented anywhere for such a large waste mass. This high recovery rate is attributed to moisture, and elevated temperature attained inexpensively during startup. Economic analyses performed under Phase I of this NETL contract indicate ''greenhouse cost effectiveness'' to be excellent. Other benefits include substantial waste volume loss (over 30%) which translates to extended landfill life. Other environmental benefits include rapidly improved quality and stabilization (lowered pollutant levels) in liquid leachate which drains from the waste.

  10. Methane recovery from landfill in China

    Energy Technology Data Exchange (ETDEWEB)

    Gaolai, L.

    1996-12-31

    GEF has approved a special project for a demonstration project for Methane Recovery from the Urban Refuse Land Fill. This paper will introduce the possibility of GHG reduction from the landfill in China, describe the activities of the GEF project, and the priorities for international cooperation in this field. The Global Environment Facility (GEF) approved the project, China Promoting Methane Recovery and Unlization from Mixed Municipal Refuse, at its Council meeting in last April. This project is the first one supported by international organization in this field.

  11. Detection and quantification of methane leakage from landfills

    Energy Technology Data Exchange (ETDEWEB)

    Ljungberg, Sven-Aake; Maartensson, Stig-Goeran (Univ. of Gaevle, Gaevle (Sweden)); Meijer, Jan-Erik; Rosqvist, Haakan (NSR AB, Helsingborg (Sweden))

    2009-03-15

    The purpose of this project was to detect gas leakage and to measure and quantify methane emission from landfills using modern remote sensing techniques. In this project, a handheld laser instrument and an IR camera were used. The overall objective was to develop cost-effective methods for detecting and quantifying methane emissions from landfills. There are many methods available for measuring the methane concentration in air, both from close-up and from long distances. Combined with the use of a tracer gas, the methane emission from entire landfills can be measured relatively accurately. A number of methods are used to detect leakage from parts of landfill surfaces, but there are few methods for quantifying leakage from sub-zones. Field measurements with the laser instrument and the IR camera were carried out at seven Swedish landfills and two landfills in France. The investigated surfaces at the Swedish landfills were divided into different zones, such as top surface, slope, crest and toe of slope. The field measurements in France were taken over entire landfills. The methane emission varied between the different landfills in the project, and also between the different landfill zones. The results from repeated field measurements indicated that a landfill with a final cap and a successful gas recovery system produces barely measurable emissions. The weak points at a landfill are generally slopes, including crests and toes of slopes. Where the covering of the waste is inadequate, leakage often occurs at lift joints and in areas where waste protrudes through the cover. Other weak points are deficiencies in the gas recovery system. Leachate systems can lead landfill gas and thereby cause methane leakage. Along with wind velocity and variations in atmospheric pressure, moisture content in the ground is an important factor that affects methane emissions from landfill surfaces. Results from field measurements of the same feature/surface at different points in time and

  12. Estimation of future methane production from Hellenic landfills

    Energy Technology Data Exchange (ETDEWEB)

    Tsatsarelis, T.; Karagiannidis, A. [Aristotle Univ., Thessaloniki (Greece). Lab. of Heat Transfer and Environmental Engineering

    2009-07-15

    Organic waste decomposition leads to the production of Landfill Gas (LFG). LFG mainly consists of methane (CH{sub 4}) and carbon dioxide (CO{sub 2}). It is common understanding now that LFG should be considered either as a significant source of pollution and risk (if migrating uncontrollably to the air and ground), or as a significant source of renewable energy (if extracted and processed accordingly). There are two possible solutions for dealing with LFG emissions. In the case of low methane ratios, LFG should be extracted and flared or oxidized in biofilters. On the other hand, in the case of high methane content, LFG becomes an evidently valuable energy resource, as it is then able to sustain the fuelling of engines producing electricity and thermal energy. More specifically, it can be used as a supplementary or primary fuel to increase the production of electric power, as a pipeline quality gas and vehicle fuel, or even as a supply of heat and carbon dioxide for greenhouses and various industrial processes. Technologies that utilize LFG include internal combustion engines, gas turbines, fuel cells and boiler systems. The main objective of this research was to predict expected methane generation in Hellenic sanitary landfills, in order to evaluate its potential for energy production and to ensure health and safety in and around these sites on the long term. The study was performed for the period 2008--2028 with the use of a multi-phase model and included a sensitivity analysis in order to determine the impact of certain waste parameters. In this context, two 'extreme' reference scenarios were formulated and assessed, one anticipating fulfillment of the EU landfill directive (which sets limits to the amount of biodegradable and packaging materials to be deposited in sanitary landfills) whereas a second (do-nothing scenario) assuming no such timely compliance. The model used here for methane estimation is a multi-phase model developed by the Norwegian

  13. Anaerobic methane oxidation in a landfill-leachate plume.

    Science.gov (United States)

    Grossman, Ethan L; Cifuentes, Luis A; Cozzarelli, Isabelle M

    2002-06-01

    The alluvial aquifer adjacent to Norman Landfill, OK, provides an excellent natural laboratory for the study of anaerobic processes impacting landfill-leachate contaminated aquifers. We collected groundwaters from a transect of seven multilevel wells ranging in depth from 1.3 to 11 m that were oriented parallel to the flow path. The center of the leachate plume was characterized by (1) high alkalinity and elevated concentrations of total dissolved organic carbon, reduced iron, and methane, and (2) negligible oxygen, nitrate, and sulfate concentrations. Methane concentrations and stable carbon isotope (delta13C) values suggest anaerobic methane oxidation was occurring within the plume and at its margins. Methane delta13C values increased from about -54 per thousand near the source to > -10 per thousand downgradient and at the plume margins. The isotopic fractionation associated with this methane oxidation was -13.6+/-1.0 per thousand. Methane 13C enrichment indicated that 80-90% of the original landfill methane was oxidized over the 210-m transect. First-order rate constants ranged from 0.06 to 0.23 per year, and oxidation rates ranged from 18 to 230 microM/y. Overall, hydrochemical data suggest that a sulfate reducer-methanogen consortium may mediate this methane oxidation. These results demonstrate that natural attenuation through anaerobic methane oxidation can be an important sink for landfill methane in aquifer systems.

  14. Detection and quantification of methane leakage from landfills

    Energy Technology Data Exchange (ETDEWEB)

    Ljungberg, Sven-Aake; Maartensson, Stig-Goeran (Univ. of Gaevle, Gaevle (Sweden)); Meijer, Jan-Erik; Rosqvist, Haakan (NSR AB, Helsingborg (Sweden))

    2009-03-15

    The purpose of this project was to detect gas leakage and to measure and quantify methane emission from landfills using modern remote sensing techniques. In this project, a handheld laser instrument and an IR camera were used. The overall objective was to develop cost-effective methods for detecting and quantifying methane emissions from landfills. There are many methods available for measuring the methane concentration in air, both from close-up and from long distances. Combined with the use of a tracer gas, the methane emission from entire landfills can be measured relatively accurately. A number of methods are used to detect leakage from parts of landfill surfaces, but there are few methods for quantifying leakage from sub-zones. Field measurements with the laser instrument and the IR camera were carried out at seven Swedish landfills and two landfills in France. The investigated surfaces at the Swedish landfills were divided into different zones, such as top surface, slope, crest and toe of slope. The field measurements in France were taken over entire landfills. The methane emission varied between the different landfills in the project, and also between the different landfill zones. The results from repeated field measurements indicated that a landfill with a final cap and a successful gas recovery system produces barely measurable emissions. The weak points at a landfill are generally slopes, including crests and toes of slopes. Where the covering of the waste is inadequate, leakage often occurs at lift joints and in areas where waste protrudes through the cover. Other weak points are deficiencies in the gas recovery system. Leachate systems can lead landfill gas and thereby cause methane leakage. Along with wind velocity and variations in atmospheric pressure, moisture content in the ground is an important factor that affects methane emissions from landfill surfaces. Results from field measurements of the same feature/surface at different points in time and

  15. 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

  16. Quantification of methane emissions from 15 Danish landfills using the mobile tracer dispersion method

    DEFF Research Database (Denmark)

    Mønster, Jacob; Samuelsson, Jerker; Kjeldsen, Peter

    2015-01-01

    biocover installed. Landfills with gas collection and recovery systems had a recovery efficiency of 41-81%. Landfills where shredder waste was deposited showed significant methane emissions, with the largest emission from newly deposited shredder waste. The average methane emission from the landfills...

  17. Quantification of methane emissions from 15 Danish landfills using the mobile tracer dispersion method

    Energy Technology Data Exchange (ETDEWEB)

    Mønster, Jacob [Department of Environmental Engineering, Technical University of Denmark, Miljøvej – Building 113, DK-2800 Lyngby (Denmark); Samuelsson, Jerker, E-mail: jerker.samuelsson@fluxsense.se [Chalmers University of Technology/FluxSense AB, SE-41296 Göteborg (Sweden); Kjeldsen, Peter [Department of Environmental Engineering, Technical University of Denmark, Miljøvej – Building 113, DK-2800 Lyngby (Denmark); Scheutz, Charlotte, E-mail: chas@env.dtu.dk [Department of Environmental Engineering, Technical University of Denmark, Miljøvej – Building 113, DK-2800 Lyngby (Denmark)

    2015-01-15

    Highlights: • Quantification of whole landfill site methane emission at 15 landfills. • Multiple on-site source identification and quantification. • Quantified methane emission from shredder waste and composting. • Large difference between measured and reported methane emissions. - Abstract: Whole-site methane emissions from 15 Danish landfills were assessed using a mobile tracer dispersion method with either Fourier transform infrared spectroscopy (FTIR), using nitrous oxide as a tracer gas, or cavity ring-down spectrometry (CRDS), using acetylene as a tracer gas. The landfills were chosen to represent the different stages of the lifetime of a landfill, including open, active, and closed covered landfills, as well as those with and without gas extraction for utilisation or flaring. Measurements also included landfills with biocover for oxidizing any fugitive methane. Methane emission rates ranged from 2.6 to 60.8 kg h{sup −1}, corresponding to 0.7–13.2 g m{sup −2} d{sup −1}, with the largest emission rates per area coming from landfills with malfunctioning gas extraction systems installed, and the smallest emission rates from landfills closed decades ago and landfills with an engineered biocover installed. Landfills with gas collection and recovery systems had a recovery efficiency of 41–81%. Landfills where shredder waste was deposited showed significant methane emissions, with the largest emission from newly deposited shredder waste. The average methane emission from the landfills was 154 tons y{sup −1}. This average was obtained from a few measurement campaigns conducted at each of the 15 landfills and extrapolating to annual emissions requires more measurements. Assuming that these landfills are representative of the average Danish landfill, the total emission from Danish landfills were calculated at 20,600 tons y{sup −1}, which is significantly lower than the 33,300 tons y{sup −1} estimated for the national greenhouse gas inventory for

  18. 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...

  19. 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.

  20. 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......‐cost‐effective, bio‐mitigation systems may be implemented. Bio‐mitigation systems are defined here as systems based on microbial removal processes implemented at landfills to reduce emission of methane (or other harmful substances). In respect to CH4, experiments have documented that a very high methane oxidation...... 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...

  1. 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.

  2. Integrating landfill bioreactors, partial nitritation and anammox process for methane recovery and nitrogen removal from leachate

    Science.gov (United States)

    Sun, Faqian; Su, Xiaomei; Kang, Tingting; Wu, Songwei; Yuan, Mengdong; Zhu, Jing; Zhang, Xiayun; Xu, Fang; Wu, Weixiang

    2016-06-01

    A new process consisting of a landfill bioreactor, partial-nitritation (PN) and the anammox process has been developed for landfill leachate treatment. In this study, the landfill bioreactor exhibited excellent performance in methane-rich biogas recovery, with a specific biogas yield of 0.47 L gas g-1 COD and methane percentages of 53-76%. PN was achieved in the aerobic reactor by high free ammonia (101 ± 83 mg NH3 L-1) inhibition for nitrite-oxidizing bacteria, and the desired PN effluent composition (effluent nitrite: ammonium ratio of 1.1 ± 0.3) was controlled by adjusting the alkalinity concentration per unit of ammonium oxidized to approximately 14.3 mg CaCO3 mg-1 N in the influent. The startup of anammox process was successfully achieved with a membrane bioreactor in 160 d, and a maximum nitrogen removal rate of 216 mg N L-1 d-1 was attained for real landfill leachate treatment. The quantitative polymerase chain reaction results confirmed that the cell-specific anammox activity was approximately 68-95 fmol N cell-1 d-1, which finally led to the stable operation of the system.

  3. The prediction of the methane production in landfill affected by the temperature

    Directory of Open Access Journals (Sweden)

    Zhou Lianying

    2015-01-01

    Full Text Available The functional relationship between the generation rate coefficient and temperature was developed for quantitative prediction of the temperature effect in this paper. The methane production of the landfill was predicted under the condition of the seasonal variation. The results showed that considering the temperature effect, the methane production is higher than the methane production without temperature effect of the 0.14×106 m3~0.28×106m3.With the depth increasing, the effect of the atmospheric temperature fluctuation on the temperature change of the landfill was weakened. The temperature has a significant effect on the methane production in the landfill. The temperature effect should be considered when simulate the long time effect of the landfill methane production.

  4. The estimation of methane emissions from landfills with different cover systems

    Science.gov (United States)

    Park, S.; Lee, K.; Sung, K.

    2006-12-01

    Methane is a very potent greenhouse gas, second only to CO2 as an anthropogenic contributor to global warming. Landfills are important anthropogenic source in the CH4 emissions. Microbially mediated CH4 oxidation in landfills with conventional soil covers can serve as an efficient biological sink. Methane from modern sanitary landfills equipped with composite covers and gas collection system is vented directly to the atmosphere, except for some of the largest landfills at which it is collected and burned. However, previous laboratory research has shown that biofilters have the potential to reduce CH4 emissions from landfills with modern composite covers. In this study a CH4 emission model was developed. The model used the calculated CH4 oxidation rates to estimate CH4 emissions from landfills constructed with conventional soil covers, modern composite covers, and modern composite covers plus biofilters. According to the CH4 emission rates predicted by CH4 emission model, it was estimated that 90% of the generated CH4 was emitted to the atmosphere for landfills with modern composite cover. For landfills with modern composite cover plus biofilters, an average of only 9% of the generated CH4 was estimated to be emitted. For landfills with conventional covers, an average of 83% of the generated CH4 was estimated to be emitted. By comparing the CH4 emission rates from three different landfill types, the use of a properly managed biofilter should be an effective technique to reduce CH4 emissions from landfills.

  5. 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 pilo...

  6. Temperatures In Compost Landfill Covers As Result Of Methane Oxidation And Compost Respiration

    DEFF Research Database (Denmark)

    Scheutz, Charlotte; Merono, A. R.; Pedersen, Rasmus Broen;

    2011-01-01

    This study investigated the influence of the temperature on methane (CH4) oxidation and respiration in compost sampled at a full scale biocover implemented at Klintholm landfill exhibiting high temperatures. Compost material was collected at Klintholm landfill and incubated with and without CH4...

  7. Estimating methane emissions from landfills based on rainfall, ambient temperature, and waste composition: The CLEEN model.

    Science.gov (United States)

    Karanjekar, Richa V; Bhatt, Arpita; Altouqui, Said; Jangikhatoonabad, Neda; Durai, Vennila; Sattler, Melanie L; Hossain, M D Sahadat; Chen, Victoria

    2015-12-01

    Accurately estimating landfill methane emissions is important for quantifying a landfill's greenhouse gas emissions and power generation potential. Current models, including LandGEM and IPCC, often greatly simplify treatment of factors like rainfall and ambient temperature, which can substantially impact gas production. The newly developed Capturing Landfill Emissions for Energy Needs (CLEEN) model aims to improve landfill methane generation estimates, but still require inputs that are fairly easy to obtain: waste composition, annual rainfall, and ambient temperature. To develop the model, methane generation was measured from 27 laboratory scale landfill reactors, with varying waste compositions (ranging from 0% to 100%); average rainfall rates of 2, 6, and 12 mm/day; and temperatures of 20, 30, and 37°C, according to a statistical experimental design. Refuse components considered were the major biodegradable wastes, food, paper, yard/wood, and textile, as well as inert inorganic waste. Based on the data collected, a multiple linear regression equation (R(2)=0.75) was developed to predict first-order methane generation rate constant values k as functions of waste composition, annual rainfall, and temperature. Because, laboratory methane generation rates exceed field rates, a second scale-up regression equation for k was developed using actual gas-recovery data from 11 landfills in high-income countries with conventional operation. The Capturing Landfill Emissions for Energy Needs (CLEEN) model was developed by incorporating both regression equations into the first-order decay based model for estimating methane generation rates from landfills. CLEEN model values were compared to actual field data from 6 US landfills, and to estimates from LandGEM and IPCC. For 4 of the 6 cases, CLEEN model estimates were the closest to actual.

  8. Methane oxidation and degradation of organic compounds in landfill soil covers

    DEFF Research Database (Denmark)

    Scheutz, Charlotte; Kjeldsen, Peter

    2002-01-01

    High rates of methane oxidation and degradation of the lowed halogenated methanes (TCM and DCM) and HCFCs (HCFC-21 and HCFC-22) were found in an investigation of the oxidation of methane and halogenated organic compunds (HOCs) in landfill gas affected soil. The degradation followed zero-order kin......High rates of methane oxidation and degradation of the lowed halogenated methanes (TCM and DCM) and HCFCs (HCFC-21 and HCFC-22) were found in an investigation of the oxidation of methane and halogenated organic compunds (HOCs) in landfill gas affected soil. The degradation followed zero......-order kinetics and occurred in parallel with the oxidation of methane. TeCM, CFC-11, and CFC-12 were not degradable in presence of oxygen and degradation of these compounds in the oxidative zone in landfill top covers is therefore expected to be limited. However these compounds were found degradable...... in the anaerobic zone in the lower part of soil columns permeated with artificial landfill gas. The lesser-chlorinated compounds were degraded in the upper oxic zone with overlapping gradients of methane and oxygen. Methane oxidation and degradation of HOCs in the top-soils may play a very important role...

  9. Use of stable isotopes to determine methane oxidation in landfill cover soils

    Science.gov (United States)

    Liptay, K.; Chanton, J.; Czepiel, P.; Mosher, B.

    1998-04-01

    The mean isotopic composition of CH4 emitted from six New England (United States) landfills was 13C and D enriched (-48.1 to -50.4‰ and -273 to -281‰) relative to anoxic zone landfill CH4 (mean values of -55.9 to -56.2‰ and -296 to -300‰) owing to the oxidation of methane as it was transported from the landfill to the atmosphere through the soil cap. The fraction of methane oxidized f0 during its passage through the soil cap was calculated from the degree of 13C enrichment in emitted CH4 relative to anoxic zone CH4 in conjunction with values determined for the preference of soil methane oxidizing bacteria for 12CH4 over 13CH4 (α = 1.022 ± 0.008). Mean values for methane oxidation in six landfills were from 24 to 35% of the total flux through the soil during the warm season, depending upon how the data were grouped. Our results bracket recent estimates of methane oxidation of about 30% in the warm summer period produced using a model with the input terms of soil temperature, moisture, depth, and oxygen concentration. Because of variations in the response of methane oxidation to temperature at these New England sites, our study is consistent with the modeling results of Czepiel et al. [1996b] that the best estimate for the annual value for methane oxidation in the landfills considered is about 10%.

  10. 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...

  11. Quantification of parameters influencing methane generation due to biodegradation of municipal solid waste in landfills and laboratory experiments.

    Science.gov (United States)

    Fei, Xunchang; Zekkos, Dimitrios; Raskin, Lutgarde

    2016-09-01

    The energy conversion potential of municipal solid waste (MSW) disposed of in landfills remains largely untapped because of the slow and variable rate of biogas generation, delayed and inefficient biogas collection, leakage of biogas, and landfill practices and infrastructure that are not geared toward energy recovery. A database consisting of methane (CH4) generation data, the major constituent of biogas, from 49 laboratory experiments and field monitoring data from 57 landfills was developed. Three CH4 generation parameters, i.e., waste decay rate (k), CH4 generation potential (L0), and time until maximum CH4 generation rate (tmax), were calculated for each dataset using U.S. EPA's Landfill Gas Emission Model (LandGEM). Factors influencing the derived parameters in laboratory experiments and landfills were investigated using multi-linear regression analysis. Total weight of waste (W) was correlated with biodegradation conditions through a ranked classification scheme. k increased with increasing percentage of readily biodegradable waste (Br0 (%)) and waste temperature, and reduced with increasing W, an indicator of less favorable biodegradation conditions. The values of k obtained in the laboratory were commonly significantly higher than those in landfills and those recommended by LandGEM. The mean value of L0 was 98 and 88L CH4/kg waste for laboratory and field studies, respectively, but was significantly affected by waste composition with ranges from 10 to 300L CH4/kg. tmax increased with increasing percentage of biodegradable waste (B0) and W. The values of tmax in landfills were higher than those in laboratory experiments or those based on LandGEM's recommended parameters. Enhancing biodegradation conditions in landfill cells has a greater impact on improving k and tmax than increasing B0. Optimizing the B0 and Br0 values of landfilled waste increases L0 and reduces tmax.

  12. Methane Gas Utilization Project from Landfill at Ellery (NY)

    Energy Technology Data Exchange (ETDEWEB)

    Pantelis K. Panteli

    2012-01-10

    Landfill Gas to Electric Energy Generation and Transmission at Chautauqua County Landfill, Town of Ellery, New York. The goal of this project was to create a practical method with which the energy, of the landfill gas produced by the decomposing waste at the Chautauqua County Landfill, could be utilized. This goal was accomplished with the construction of a landfill gas to electric energy plant (originally 6.4MW and now 9.6MW) and the construction of an inter-connection power-line, from the power-plant to the nearest (5.5 miles) power-grid point.

  13. Turning a Liability into an Asset: Landfill Methane Recovery in India

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    Solid waste disposal sites are not often seen as opportunities for energy solutions. The waste that is disposed in open dumps and landfills generates methane and other gases as it decomposes, causing concerns about explosions, odours, and, increasingly, about the contribution of methane to global climate change. However, the liability of landfill gas (LFG) can be turned into an asset. Many countries regularly capture LFG as a strategy to improve landfill safety, generate electricity, reduce greenhouse gas emissions, and to earn carbon emission reduction credits (e.g. 40% for the United States, 25% for Australia). Many projects in developing countries are taking advantage of the United Nations Framework Convention on Climate Change (UNFCCC) Clean Development Mechanism (CDM) to earn carbon credits by capturing and combusting methane (e.g., the Sudokwon Landfill in Republic of South Korea, the Bandeirantes Landfill in Brazil and the Nanjing Tianjingwa Landfill in China). These Landfill Gas to Energy (LFGE) projects provide a valuable service to the environment and a potentially profitable business venture, providing benefits to local and regional communities.

  14. Estimation of Methane Emissions from Municipal Solid Waste Landfills in China Based on Point Emission Sources

    Institute of Scientific and Technical Information of China (English)

    CAI Bo-Feng; LIU Jian-Guo; GAO Qing-Xian; NIE Xiao-Qin; CAO Dong; LIU Lan-Cui; ZHOU Ying; ZHANG Zhan-Sheng

    2014-01-01

    The methane (CH4) emissions from municipal solid waste (MSW) landfills in China in 2007 were estimated based on database of the three-dimensional emission factors matrix and point sources, by an IPCC recommended FOD (first-order decay) model. The location, capacity and age of landfills constitute the three dimensions of the emission factors matrix, which were obtained by laboratory analysis and in situ investigation. Key parameters such as waste composition, degradable organic carbon ratio, CH4 correction factor, oxidation factor and recovery rate, were carefully analyzed in terms of these three dimensions. The point sources database consists of 2,107 MSW landfills in cities and towns of China in 2007. The results show that the CH4 emissions from MSW landfills were 1.186 Mt in 2007. Compared with the CH4 emissions of 2.20 Mt in 2005, the significant discrepancy mainly comes from statistical data of landfills, e.g., number of landfills and amount of waste disposed in landfills. CH4 emissions were lower than 700 t for most of the landfills, whereas there were 279 landfills with emissions larger than 1,000 t, and only 10 landfills with emissions larger than 10,000 t. Jiangsu province ranks the largest emitter with 98,700 t while Tibet is the smallest emitter with 2,100 t. In general, the emissions from eastern provinces, such as Jiangsu, Guangdong and Zhejiang, were larger than those from western provinces, such as Ningxia, Tibet and Qinghai.

  15. Site specific diel methane emission mechanisms in landfills: A field validated process based on vegetation and climate factors.

    Science.gov (United States)

    Xin, Danhui; Hao, Yongxia; Shimaoka, Takayuki; Nakayama, Hirofumi; Chai, Xiaoli

    2016-11-01

    Diel methane emission fluxes from a landfill that was covered by vegetation were investigated to reveal the methane emission mechanisms based on the interaction of vegetation characteristics and climate factors. The methane emissions showed large variation between daytime and nighttime, and the trend of methane emissions exhibited clear bimodal patterns from both Setaria viridis- and Neyraudia reynaudiana-covered areas. Plants play an important role in methane transportation as well as methane oxidation. The notable decrease in methane emissions after plants were cut suggests that methane transportation via plants is the primary way of methane emissions in the vegetated areas of landfill. Within plants, the methane emission fluxes were enhanced due to a convection mechanism. Given that the methane emission flux is highly correlated with the solar radiation during daytime, the convection mechanism could be attributed to the increase in solar radiation. Whereas the methane emission flux is affected by a combined impact of the wind speed and pedosphere characteristics during nighttime. An improved understanding of the methane emission mechanisms in vegetated landfills is expected to develop a reliable model for landfill methane emissions and to attenuate greenhouse gas emissions from landfills.

  16. Operating a fuel cell using landfill gas

    Energy Technology Data Exchange (ETDEWEB)

    Trippel, C.E.; Preston, J.L. Jr.; Trocciola, J.; Spiegel, R.

    1996-12-31

    An ONSI PC25{trademark}, 200 kW (nominal capacity) phosphoric acid fuel cell operating on landfill gas is installed at the Town of Groton Flanders Road landfill in Groton, Connecticut. This joint project by the Connecticut Light & Power Company (CL&P) which is an operating company of Northeast Utilities, the Town of Groton, International Fuel Cells (IFC), and the US EPA is intended to demonstrate the viability of installing, operating and maintaining a fuel cell operating on landfill gas at a landfill site. The goals of the project are to evaluate the fuel cell and gas pretreatment unit operation, test modifications to simplify the GPU design and demonstrate reliability of the entire system.

  17. USING LANDFILL GAS IN FUEL CELLS - A STEP CLOSER TO COMMERICAL REALITY

    Science.gov (United States)

    The article discusses Phase II and Phase III results of a U.S. EPA program underway at International Fuel Cells Corporation. The program involves controlling methane emissions from landfills using a fuel cell. The fuel cell would reduce air emissions affecting global warming, aci...

  18. Neural Network Modeling and Prediction of Methane Fraction in Biogas from Landfill Bioreactors

    Directory of Open Access Journals (Sweden)

    A Ghavidel

    2009-09-01

    Full Text Available "n "nBackgrounds and Objectives:A number of different technologies have recently been studied todetermine the best use of biogas, however, to choose optimize technologies of using biogas for energy recovery it is necessary to monitor and predict the methane percentage of biogas. In this study, a method is proposed for predicting the methane fraction in landfill gas originating from Labscalelandfill bioreactors, based on neural network."nMaterials and Methods: In this study, two different systems were applied, to predict the methane fraction in landfill gas as a final product of anaerobic digestion, we used the leachate specifications as input parameters. In system I (C1, the leachate generated from a fresh-waste reactor was drained to recirculation tank, and recycled. In System II (C2, the leachate generated from a fresh waste landfill reactor was fed through a well-decomposed refuse landfill reactor, and at the same time, the leachate generated from a well-decomposed refuse landfill reactor recycled to a fresh waste landfill reactor."nResults: There is very good agreement in the trends between forecasted and measured data. R valuesare 0.999 and 0.997, and the obtained Root mean square error values are 1.098 and 2.387 for training and test data, respectively"nConclusion: The proposed method can significantly predict the methane fraction in landfill gasoriginating and, consequently, neural network can be use to optimize the dimensions of a plant using biogas for energy (i.e. heat and/or electricity recovery and monitoring system.

  19. Effects of methane on the microbial populations and oxidation rates in different landfill cover soil columns.

    Science.gov (United States)

    He, Ruo; Ruan, Aidong; Shen, Dong-Sheng

    2007-05-01

    A considerable fraction of methane produced in landfills is oxidized by landfill cover soils. In this work, microbial populations and oxidation rates developed in response to the presence of methane were studied in three soil columns simulated landfill cover soil environments. The population of aerobic heterotrophic bacteria was highest in the waste soil, middle in the clay soil, and lowest in the red soil. After exposure to methane-rich environments, the populations of methanotrophic bacteria showed increases in the waste and clay soils. The population of methanotrophic bacteria increased from 30.77x10(4) to 141.77x10(4) cfu g d.w.-1 in the middle layer of the waste soil column as a function of exposure to methane for 120 days. The populations of methanotrophic bacteria were correlated with the potential methane oxidation rates in the waste and clay soils, respectively. The topsoil was observed to be dried in the three soil columns. Most of methane oxidation occurred at the depth of between 10 and 20 cm in the waste soil column, while it took place mainly at the depth of between 20 and 30 cm in the clay soil column.

  20. Lateral gas transport in soil adjacent to an old landfill: factors governing emissions and methane oxidation

    DEFF Research Database (Denmark)

    Christophersen, Mette; Kjeldsen, Peter; Holst, Helle;

    2001-01-01

    influence on the fluxes, as did the distance from the landfill border, temperature, barometric pressure and the pressure gradient. Statistical analyses proved that soil moisture described the largest part of the variation. No methane at all emitted during the summer. Calculations and isotope analyses showed...

  1. Estimation of Methane Emissions from Municipal Solid Waste Landfills in China Based on Point Emission Sources

    Directory of Open Access Journals (Sweden)

    Cai Bo-Feng

    2014-01-01

    Citation: Cai, B.-F., Liu, J.-G., Gao, Q.-X., et al., 2014. Estimation of methane emissions from municipal solid waste landfills in China based on point emission sources. Adv. Clim. Change Res. 5(2, doi: 10.3724/SP.J.1248.2014.081.

  2. Assessing methods to estimate emissions of non-methane organic compounds from landfills

    DEFF Research Database (Denmark)

    Saquing, Jovita M.; Chanton, Jeffrey P.; Yazdani, Ramin;

    2014-01-01

    The non-methane organic compound (NMOC) emission rate is used to assess compliance with landfill gas emission regulations by the United States Environmental Protection Agency (USEPA). A recent USEPA Report (EPA/600/R-11/033) employed a ratio method to estimate speciated NMOC emissions (i...

  3. Methane emissions measured at two California landfills by OTM-10 and an acetylene tracer method

    Science.gov (United States)

    Methane emissions were measured at two municipal solid waste landfills in California using static flux chambers, an optical remote sensing approach known as vertical radial plume mapping (VRPM) using a tunable diode laser (TDL) and a novel acetylene tracer method. The tracer meth...

  4. The effects of leachate recirculation with supplemental water addition on methane production and waste decomposition in a simulated tropical landfill.

    Science.gov (United States)

    Sanphoti, N; Towprayoon, S; Chaiprasert, P; Nopharatana, A

    2006-10-01

    In order to increase methane production efficiency, leachate recirculation is applied in landfills to increase moisture content and circulate organic matter back into the landfill cell. In the case of tropical landfills, where high temperature and evaporation occurs, leachate recirculation may not be enough to maintain the moisture content, therefore supplemental water addition into the cell is an option that could help stabilize moisture levels as well as stimulate biological activity. The objectives of this study were to determine the effects of leachate recirculation and supplemental water addition on municipal solid waste decomposition and methane production in three anaerobic digestion reactors. Anaerobic digestion with leachate recirculation and supplemental water addition showed the highest performance in terms of cumulative methane production and the stabilization period time required. It produced an accumulated methane production of 54.87 l/kg dry weight of MSW at an average rate of 0.58 l/kg dry weight/d and reached the stabilization phase on day 180. The leachate recirculation reactor provided 17.04 l/kg dry weight at a rate of 0.14l/kg dry weight/d and reached the stabilization phase on day 290. The control reactor provided 9.02 l/kg dry weight at a rate of 0.10 l/kg dry weight/d, and reached the stabilization phase on day 270. Increasing the organic loading rate (OLR) after the waste had reached the stabilization phase made it possible to increase the methane content of the gas, the methane production rate, and the COD removal. Comparison of the reactors' efficiencies at maximum OLR (5 kgCOD/m(3)/d) in terms of the methane production rate showed that the reactor using leachate recirculation with supplemental water addition still gave the highest performance (1.56 l/kg dry weight/d), whereas the leachate recirculation reactor and the control reactor provided 0.69 l/kg dry weight/d and 0.43 l/kg dry weight/d, respectively. However, when considering

  5. Evaluation of respiration in compost landfill biocovers intended for methane oxidation

    DEFF Research Database (Denmark)

    Scheutz, Charlotte; Pedicone, Alessio; Pedersen, Gitte Bukh;

    2011-01-01

    A low-cost alternative approach to reduce landfill gas (LFG) emissions is to integrate compost into the landfill cover design in order to establish a biocover that is optimized for biological oxidation of methane (CH4). A laboratory and field investigation was performed to quantify respiration...... in an experimental compost biocover in terms of oxygen (O2) consumption and carbon dioxide (CO2) production and emission rates. O2 consumption and CO2 production rates were measured in batch and column experiments containing compost sampled from a landfill biowindow at Fakse landfill in Denmark. Column gas...... concentration profiles were compared to field measurements. Column studies simulating compost respiration in the biowindow showed average CO2 production and O2 consumption rates of 107±14gm−2d−1 and 63±12gm−2d−1, respectively. Gas profiles from the columns showed elevated CO2 concentrations throughout...

  6. 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...

  7. FUEL CELL ENERGY RECOVERY FROM LANDFILL GAS

    Science.gov (United States)

    International Fuel Cells Corporation is conducting a US Environmental Protection Agency (EPA) sponsored program to demonstrate energy recovery from landfill gas using a commercial phosphoric acid fuel cell power plant. The US EPA is interested in fuel cells for this application b...

  8. Application of portable gas detector in point and scanning method to estimate spatial distribution of methane emission in landfill.

    Science.gov (United States)

    Lando, Asiyanthi Tabran; Nakayama, Hirofumi; Shimaoka, Takayuki

    2017-01-01

    Methane from landfills contributes to global warming and can pose an explosion hazard. To minimize these effects emissions must be monitored. This study proposed application of portable gas detector (PGD) in point and scanning measurements to estimate spatial distribution of methane emissions in landfills. The aims of this study were to discover the advantages and disadvantages of point and scanning methods in measuring methane concentrations, discover spatial distribution of methane emissions, cognize the correlation between ambient methane concentration and methane flux, and estimate methane flux and emissions in landfills. This study was carried out in Tamangapa landfill, Makassar city-Indonesia. Measurement areas were divided into basic and expanded area. In the point method, PGD was held one meter above the landfill surface, whereas scanning method used a PGD with a data logger mounted on a wire drawn between two poles. Point method was efficient in time, only needed one person and eight minutes in measuring 400m(2) areas, whereas scanning method could capture a lot of hot spots location and needed 20min. The results from basic area showed that ambient methane concentration and flux had a significant (pmethane emissions in the expanded area by using Kriging method. The average of estimated flux from scanning method was 71.2gm(-2)d(-1) higher than 38.3gm(-2)d(-1) from point method. Further, scanning method could capture the lower and higher value, which could be useful to evaluate and estimate the possible effects of the uncontrolled emissions in landfill.

  9. 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

    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...

  10. Effect of enzyme additions on methane production and lignin degradation of landfilled sample of municipal solid waste.

    Science.gov (United States)

    Jayasinghe, P A; Hettiaratchi, J P A; Mehrotra, A K; Kumar, Sunil

    2011-04-01

    Operation of waste cells as landfill bioreactors with leachate recirculation is known to accelerate waste degradation and landfill gas generation. However, waste degradation rates in landfill bioreactors decrease with time, with the accumulation of difficult to degrade materials, such as lignin-rich waste. Although, potential exists to modify the leachate quality to promote further degradation of such waste, very little information is available in literature. The objective of this study was to determine the viability of augmenting leachate with enzymes to increase the rate of degradation of lignin-rich waste materials. Among the enzymes evaluated MnP enzyme showed the best performance in terms of methane yield and substrate (lignin) utilization. Methane production of 200 mL CH(4)/g VS was observed for the MnP amended reactor as compared to 5.7 mL CH(4)/g VS for the control reactor. The lignin reduction in the MnP amended reactor and control reactor was 68.4% and 6.2%, respectively.

  11. Evaluation of methane emissions from Palermo municipal landfill: Comparison between field measurements and models.

    Science.gov (United States)

    Di Bella, Gaetano; Di Trapani, Daniele; Viviani, Gaspare

    2011-08-01

    Methane (CH(4)) diffuse emissions from Municipal Solid Waste (MSW) landfills represent one of the most important anthropogenic sources of greenhouse gas. CH(4) is produced by anaerobic biodegradation of organic matter in landfilled MSW and constitutes a major component of landfill gas (LFG). Gas recovery is a suitable method to effectively control CH(4) emissions from landfill sites and the quantification of CH(4) emissions represents a good tool to evaluate the effectiveness of a gas recovery system in reducing LFG emissions. In particular, LFG emissions can indirectly be evaluated from mass balance equations between LFG production, recovery and oxidation in the landfill, as well as by a direct approach based on LFG emission measurements from the landfill surface. However, up to now few direct measurements of landfill CH(4) diffuse emissions have been reported in the technical literature. In the present study, both modeling and direct emission measuring methodologies have been applied to the case study of Bellolampo landfill located in Palermo, Italy. The main aim of the present study was to evaluate CH(4) diffuse emissions, based on direct measurements carried out with the flux accumulation chamber (static, non-stationary) method, as well as to obtain the CH(4) contoured flux map of the landfill. Such emissions were compared with the estimate achieved by means of CH(4) mass balance equations. The results showed that the emissions obtained by applying the flux chamber method are in good agreement with the ones derived by the application of the mass balance equation, and that the evaluated contoured flux maps represent a reliable tool to locate areas with abnormal emissions in order to optimize the gas recovery system efficiency.

  12. Livingston Parish Landfill Methane Recovery Project (Feasibility Study)

    Energy Technology Data Exchange (ETDEWEB)

    White, Steven

    2012-11-15

    The Woodside Landfill is owned by Livingston Parish, Louisiana and is operated under contract by Waste Management of Louisiana LLC. This public owner/private operator partnership is commonplace in the solid waste industry today. The landfill has been in operation since approximately 1988 and has a permitted capacity of approximately 41 million cubic yards. Based on an assumed in-place waste density of 0.94 ton per cubic yard, the landfill could have an expected design capacity of 39.3 million tons. The landfill does have an active landfill gas collection and control system (LFGCCS) in place because it meets the minimum thresholds for the New Source Performance Standards (NSPS). The initial LFGCS was installed prior to 2006 and subsequent phases were installed in 2007 and 2010. The Parish received a grant from the United States Department of Energy in 2009 to evaluate the potential for landfill gas recovery and utilization at the Woodside Landfill. This includes a technical and economic feasibility study of a project to install a landfill gas to energy (LFGTE) plant and to compare alternative technologies. The LFGTE plant can take the form of on-site electrical generation, a direct use/medium Btu option, or a high-Btu upgrade technology. The technical evaluation in Section 2 of this report concludes that landfill gas from the Woodside landfill is suitable for recovery and utilization. The financial evaluations in sections 3, 4, and 5 of this report provide financial estimates of the returns for various utilization technologies. The report concludes that the most economically viable project is the Electricity Generation option, subject to the Parish’s ability and willingness to allocate adequate cash for initial capital and/or to obtain debt financing. However, even this option does not present a solid return: by our estimates, there is a 19 year simple payback on the electricity generation option. All of the energy recovery options discussed in this report

  13. 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

  14. Measurements of methane emissions from landfills using mobile plume method with trace gas and cavity ring-down spectroscopy

    Science.gov (United States)

    Mønster, J.; Kjeldsen, P.; Scheutz, C.

    2012-04-01

    Methane is emitted to the atmosphere from both anthropogenic and natural sources. One of the major anthropogenic sources is methane produced by bacteria in anaerobic environments such as rice pads and landfills. Land filling has for many years been the preferred waste disposal method, resulting in a large methane production with a large contribution to the global increase in atmospheric green house gas concentration. Several steps have been taken to reduce the emission of methane from landfills. In order to validate the effect of these steps, a measurement method is needed to quantify methane emissions with a large spatial variation. One method is to use a highly sensitive and fast analytical method, capable of measuring the atmospheric concentration methane downwind from emission areas. Combined with down-wind measurements of a trace gas, emitted at a controlled mass flow rate, the methane emission can be calculated. This method is called the mobile plume method, as the whole plume is measured by doing several transects. In the current study a methane/acetylene analyzer with cavity ring-down spectroscopy detection (Picarro, G2203) was used to estimate methane from a number of Danish landfills. We measured at both active and closed landfills and investigated the difference in methane emission. At landfills where the emissions could have more than one origin, the source strength of the different emission areas was determined by accurate trace gas positioning and choosing appropriate wind speed and measurement distance. To choose these factors, we addressed the uncertainties and limitations of the method with respect to the configuration of the trace gas bottles and the distance between the emission area and the measurement points. Composting of organic material in large piles was done at several of the investigated landfills and where possible, the methane emission from this partly anaerobic digestion was measured as a separate emission.

  15. Landfills

    Data.gov (United States)

    Vermont Center for Geographic Information — This data set defines both current and historic landfills/waste disposal storage sites for the State of Vermont. Historic landfills were identified with the...

  16. Field-scale treatment of landfill gas with a passive methane oxidizing biofilter

    Energy Technology Data Exchange (ETDEWEB)

    Philopoulos, A. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil and Environmental Engineering; Felske, C. [Alberta Research Council, Edmonton, AB (Canada); McCartney, D. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil and Environmental Engineering, Natural Resources Engineering Facility

    2008-09-15

    Municipal solid waste (MSW) landfills produce methane (CH{sub 4}) and carbon dioxide (CO{sub 2}) as a result of the anaerobic biodegradation of organic fractions of waste. This paper provided details of field tests conducted to test 2 approaches that addressed the issue of gases produced at a landfill in Alberta. A CH{sub 4} oxidation layer was applied to replace intermediate and final landfill covers. Landfill gas (LFG) was then trapped using 3 biogenic CH{sub 4} oxidizing biofilters. Mature yard waste was used as a biofilter medium. The LFG was trapped by the liner, accumulated in a collection system, and then passed through the biofilter medium. The study was conducted over a period of 10 months. Results of the study showed that the integration of the biofilter into the landfill cover showed promising results. Low surface emissions were observed in 6 out of 8 monitoring events at 2 of the sites. Low influent LFG fluxes at the third site did not allow for full air sampling analyses to be conducted. 22 refs., 4 tabs., 8 figs.

  17. Modeling of methane oxidation in landfill cover soil using an artificial neural network.

    Science.gov (United States)

    Abushammala, Mohammed F M; Basri, Noor Ezlin Ahmad; Elfithri, Rahmah; Younes, Mohammad K; Irwan, Dani

    2014-02-01

    Knowing the fraction of methane (CH4) oxidized in landfill cover soils is an important step in estimating the total CH4 emissions from any landfill. Predicting CH4 oxidation in landfill cover soils is a difficult task because it is controlled by a number of biological and environmental factors. This study proposes an artificial neural network (ANN) approach using feedforward backpropagation to predict CH4 oxidation in landfill cover soil in relation to air temperature, soil moisture content, oxygen (O2) concentration at a depth of 10 cm in cover soil, and CH4 concentration at the bottom of cover soil. The optimum ANN model giving the lowest mean square error (MSE) was configured from three layers, with 12 and 9 neurons at the first and the second hidden layers, respectively, log-sigmoid (logsig) transfer function at the hidden and output layers, and the Levenberg-Marquardt training algorithm. This study revealed that the ANN oxidation model can predict CH4 oxidation with a MSE of 0.0082, a coefficient of determination (R2) between the measured and predicted outputs of up to 0.937, and a model efficiency (E) of 0.8978. To conclude, further developments of the proposed ANN model are required to generalize and apply the model to other landfills with different cover soil properties.

  18. High Frequency Measurements of Methane Concentrations and Carbon Isotopes at a Marsh and Landfill

    Science.gov (United States)

    Mortazavi, B.; Wilson, B.; Chanton, J.; Eller, K.; Dong, F.; Baer, D. S.; Gupta, M.; Dzwonkowski, B.

    2012-12-01

    High frequency measurements of methane concentrations and carbon isotopes can help constrain the source strengths of methane emitted to the atmosphere. We report here methane concentrations and 13C values measured at 0.5 Hz with cavity enhanced laser absorption spectrometers (Los Gatos Research) deployed at a saltmarsh in Alabama and a landfill in Florida. Methane concentrations and 13C at the saltmarsh were monitored over a 2.5 day time period at 2 m, 0.5 m above the ground as well as from the outflow of a flow-through (2 L) chamber placed on the Spartina alterniflora dominated marsh. A typical measurement cycle included regular samples from two tanks of known methane concentrations and isotopic values and from ambient air samples. Over the 2.5-day measurement period methane concentrations and isotopic ratios at 2 m averaged 1.85 ppm and -43.57‰ (±0.34, 1 SE), respectively. The concentration and isotopic values from the chamber outflow varied from 1.92 to 5.81 ppm and -38.5 to -59.3‰, respectively. Methane flux from the marsh ranged from undetectable to 3.6 mgC m-2hr-1, with high fluxes measured during low tide. The 13δCH4 of the emitted CH4 from the marsh, determined from a mass balance equation using the chamber inflow and outflow concentration and isotopic values ranged from -62.1 to -93.9‰ and averaged -77‰ (±1.25, 1SE). At the landfill ambient methane concentrations and 13C ratios measured over multiple days varied from 4.25 to 11.91 ppm and from -58.81 to -45.12‰, respectively. At higher methane concentrations the δ13C of CH4 was more depleted consistent with previously observed relationship at this site made by more traditional techniques. Over a 30-minute measurement period CH4 concentrations at the landfill could vary by as much as 15 ppm. The high frequency continuous optical measurements with field-deployed instruments provide us with an unprecedented temporal resolution of CH4 concentrations and isotopic ratios. These measurements will

  19. Comparison of first-order-decay modeled and actual field measured municipal solid waste landfill methane data.

    Science.gov (United States)

    Amini, Hamid R; Reinhart, Debra R; Niskanen, Antti

    2013-12-01

    The first-order decay (FOD) model is widely used to estimate landfill gas generation for emissions inventories, life cycle assessments, and regulation. The FOD model has inherent uncertainty due to underlying uncertainty in model parameters and a lack of opportunities to validate it with complete field-scale landfill data sets. The objectives of this paper were to estimate methane generation, fugitive methane emissions, and aggregated collection efficiency for landfills through a mass balance approach using the FOD model for gas generation coupled with literature values for cover-specific collection efficiency and methane oxidation. This study is unique and valuable because actual field data were used in comparison with modeled data. The magnitude and variation of emissions were estimated for three landfills using site-specific model parameters and gas collection data, and compared to vertical radial plume mapping emissions measurements. For the three landfills, the modeling approach slightly under-predicted measured emissions and over-estimated aggregated collection efficiency, but the two approaches yielded statistically equivalent uncertainties expressed as coefficients of variation. Sources of uncertainty include challenges in large-scale field measurement of emissions and spatial and temporal fluctuations in methane flow balance components (generated, collected, oxidized, and emitted methane). Additional publication of sets of field-scale measurement data and methane flow balance components will reduce the uncertainty in future estimates of fugitive emissions.

  20. 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...... 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...... values of 51.8–69.6 and 106.6–117.3 kg CH4/ton waste on average, respectively, and DOCC values of 3.84–5.12% and 7.96–8.74% of total weight. The same category of waste from different Danish landfills did not show significant variation. This research studied the BMP of Danish low-organic waste...

  1. Methane oxidation in a landfill cover soil reactor: Changing of kinetic parameters and microorganism community structure.

    Science.gov (United States)

    Xing, Zhi L; Zhao, Tian T; Gao, Yan H; Yang, Xu; Liu, Shuai; Peng, Xu Y

    2017-02-23

    Changing of CH4 oxidation potential and biological characteristics with CH4 concentration was studied in a landfill cover soil reactor (LCSR). The maximum rate of CH4 oxidation reached 32.40 mol d(-1) m(-2) by providing sufficient O2 in the LCSR. The kinetic parameters of methane oxidation in landfill cover soil were obtained by fitting substrate diffusion and consumption model based on the concentration profile of CH4 and O2. The values of [Formula: see text] (0.93-2.29%) and [Formula: see text] (140-524 nmol kgsoil-DW(-1)·s(-1)) increased with CH4 concentration (9.25-20.30%), while the values of [Formula: see text] (312.9-2.6%) and [Formula: see text] (1.3 × 10(-5) to 9.0 × 10(-3) nmol mL(-1) h(-1)) were just the opposite. MiSeq pyrosequencing data revealed that Methylobacter (the relative abundance was decreased with height of LCSR) and Methylococcales_unclassified (the relative abundance was increased expect in H 80) became the key players after incubation with increasing CH4 concentration. These findings provide information for assessing CH4 oxidation potential and changing of biological characteristics in landfill cover soil.

  2. Adsorption and transport of methane in landfill cover soil amended with waste-wood biochars.

    Science.gov (United States)

    Sadasivam, Bala Yamini; Reddy, Krishna R

    2015-08-01

    The natural presence of methane oxidizing bacteria (MOB) in landfill soils can stimulate the bio-chemical oxidation of CH4 to CO2 and H2O under suitable environmental conditions. This mechanism can be enhanced by amending the landfill cover soil with organic materials such as biochars that are recalcitrant to biological degradation and are capable of adsorbing CH4 while facilitating the growth and activity of MOB within their porous structure. Several series of batch and small-scale column tests were conducted to quantify the CH4 sorption and transport properties of landfill cover soil amended with four types of waste hardwood biochars under different levels of amendment percentages (2, 5 and 10% by weight), exposed CH4 concentrations (0-1 kPa), moisture content (dry, 25% and 75% water holding capacity), and temperature (25, 35 and 45 °C). The linear forms of the pseudo second-order kinetic model and the Langmuir isotherm model were used to determine the kinetics and the maximum CH4 adsorption capacity of cover materials. The maximum CH4 sorption capacity of dry biochar-amended soils ranged from 1.03 × 10(-2) to 7.97 × 10(-2) mol kg(-1) and exhibited a ten-fold increase compared to that of soil with 1.9 × 10(-3) mol kg(-1). The isosteric heat of adsorption for soil was negative and ranged from -30 to -118 kJ/mol, while that of the biochar-amended soils was positive and ranged from 24 to 440 kJ/mol. The CH4 dispersion coefficients for biochar-amended soils obtained through predictive transport modeling indicated that amending the soil with biochar enhanced the methane transport rates by two orders of magnitude, thereby increasing their potential for enhanced exchange of gases within the cover system. Overall, the use of hardwood biochars as a cover soil amendment to reduce methane emissions from landfills appears to be a promising alternative to conventional soil covers.

  3. Variation of Coenzyme F420 Activity and Methane Yield in Landfill Simulation of Organic Waste

    Institute of Scientific and Technical Information of China (English)

    CHENG Yun-huan; SANG Shu-xun; HUANG Hua-zhou; LIU Xiao-juan; OUYANG Jin-bao

    2007-01-01

    A simulated landfill anaerobic bioreactor was used to characterize the anaerobic biodegradation and biogas generation of organic waste which was mainly composed of residuals of vegetables and foods. We investigated the dynamics of the coenzyme F420 activity and determined correlations between biogas yields, methane yields, methane concentration and coenzyme F420 activity. The experiment was carried out under different conditions from control without any treatment, addition of Fe3+, microorganism inoculation to a combination of Fe3+ addition and inoculation at a temperature of 36±2 ℃. The experiment was lasted 120 d and coenzyme F420 activity was analyzed using ultraviolet spectrophotometry. Experimental results indicated that activity of the coenzyme F420 treated by Fe3+ and microorganism inoculation increased substantially. The waste treated by inoculation had the greatest increase. When the waste was treated by Fe3+, inoculation and the combination of Fe3+ and inoculation, biogas yields increased by 46.9%, 132.6% and 153.1%, respectively; while the methane yields increased 4, 97 and 98 times. Methane concentration varied between 0 and 6% in the control reactor, from 0 to 14% for waste treated by the addition of Fe3+, from 0 to 59% for waste treated by inoculation and from 0 to 63% for waste treated by Fe3+ addition and inoculation. Correlations between coenzyme F420 activity and biogas production, methane production and methane concentration proved to be positively significant (p<0.05), except for the control. Consequently, coenzyme F420 activity could be used as an index for monitoring the ac-tivity of methanogens during anaerobic biodegradation of the organic fraction of municipal solid waste.

  4. Children living near a sanitary landfill have increased breath methane and Methanobrevibacter smithii in their intestinal microbiota.

    Science.gov (United States)

    de Araujo Filho, Humberto Bezerra; Carmo-Rodrigues, Mirian Silva; Mello, Carolina Santos; Melli, Lígia Cristina Fonseca Lahoz; Tahan, Soraia; Pignatari, Antonio Carlos Campos; de Morais, Mauro Batista

    2014-01-01

    This study evaluated the breath CH4 excretion and concentration of M. smithii in intestinal microbiota of schoolchildren from 2 slums. One hundred and eleven children from a slum near a sanitary landfill, 35 children of a slum located away from the sanitary landfill, and 32 children from a high socioeconomic level school were included in the study. Real-time PCR was performed to quantify the M. smithii nifH gene and it was present in the microbiota of all the participating children, with higher (P landfill (3.16 × 10(7) CFU/g of feces), comparing with the children from the slum away from the landfill (2.05 × 10(6) CFU/g of feces) and those from the high socioeconomic level group (3.93 × 10(5) CFU/g of feces). The prevalence of children who present breath methane was 53% in the slum near the landfill, 31% in the slum further away from the landfill and, 22% in the high socioeconomic level group. To live near a landfill is associated with higher concentrations of M. smithii in intestinal microbiota, comparing with those who live away from the landfill, regardless of their socioeconomics conditions.

  5. Ammonium-dependent regulation of aerobic methane-consuming bacteria in landfill cover soil by leachate irrigation.

    Science.gov (United States)

    Lü, Fan; He, Pinjing; Guo, Min; Yang, Na; Shao, Liming

    2012-01-01

    The impacts of landfill leachate irrigation on methane oxidation activities and methane-consuming bacteria populations were studied by incubation of landfill cover soils with leachate and (NH4)2SO4 solution at different ammonium concentrations. The community structures and abundances of methane-oxidizing bacteria (MOB) and ammonia-oxidizing bacteria (AOB) were examined by PCR-DGGE and real-time PCR. Compared with the pure (NH4)2SO4 solution, leachate addition was found to have a positive effect on methane oxidation activity. In terms of the irrigation amount, ammonium in leachate was responsible for the actual inhibition of leachate. The extent of inhibitory effect mainly depended on its ammonium concentration. The suppression of the predominant methane-consuming bacteria, type I MOB, was responsible for the decreased methane oxidation activity by ammonium inhibition. Methane-consuming bacteria responded diversely in abundance to ammonium. The abundance of type I MOB decreased by fivefold; type II MOB showed stimulation response of fivefold magnification upon the first addition but lessened to be lower than the original level after the second addition; the amount of AOB was stimulated to increase for 20-30 times gradually. Accumulated nitrate from nitrification strengthened the ammonium inhibition on type I and type II MOB, as a result, repetitive irrigation was unfavorable for methane oxidation.

  6. 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

    by several environmental factors such as soil texture, temperature, soil moisture content, methane and oxygen supply, and nutrients, and both soils and compost materials have been shown to exhibit high methane oxidation rates. For compost materials high methane oxidation is observed even during cold periods...... 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...

  7. Quantification of landfill methane using modified Intergovernmental Panel on Climate Change's waste model and error function analysis.

    Science.gov (United States)

    Govindan, Siva Shangari; Agamuthu, P

    2014-10-01

    Waste management can be regarded as a cross-cutting environmental 'mega-issue'. Sound waste management practices support the provision of basic needs for general health, such as clean air, clean water and safe supply of food. In addition, climate change mitigation efforts can be achieved through reduction of greenhouse gas emissions from waste management operations, such as landfills. Landfills generate landfill gas, especially methane, as a result of anaerobic degradation of the degradable components of municipal solid waste. Evaluating the mode of generation and collection of landfill gas has posted a challenge over time. Scientifically, landfill gas generation rates are presently estimated using numerical models. In this study the Intergovernmental Panel on Climate Change's Waste Model is used to estimate the methane generated from a Malaysian sanitary landfill. Key parameters of the model, which are the decay rate and degradable organic carbon, are analysed in two different approaches; the bulk waste approach and waste composition approach. The model is later validated using error function analysis and optimum decay rate, and degradable organic carbon for both approaches were also obtained. The best fitting values for the bulk waste approach are a decay rate of 0.08 y(-1) and degradable organic carbon value of 0.12; and for the waste composition approach the decay rate was found to be 0.09 y(-1) and degradable organic carbon value of 0.08. From this validation exercise, the estimated error was reduced by 81% and 69% for the bulk waste and waste composition approach, respectively. In conclusion, this type of modelling could constitute a sensible starting point for landfills to introduce careful planning for efficient gas recovery in individual landfills.

  8. Ammonium-dependent regulation of aerobic methane-consuming bacteria in landfill cover soil by leachate irrigation

    Institute of Scientific and Technical Information of China (English)

    Fan Lü; Pinjing He; Min Guo; Na Yang; Liming Shao

    2012-01-01

    The impacts of landfill leachate irrigation on methane oxidation activities and methane-consuming bacteria populations were studied by incubation of landfill cover soils with leachate and (NH4)2SO4 solution at different ammonium concentrations.The community structures and abundances of methane-oxidizing bacteria (MOB) and ammonia-oxidizing bacteria (AOB) were examined by PCRDGGE and real-time PCR.Compared with the pure (NH4)2SO4 solution,leachate addition was found to have a positive effect on methane oxidation activity.In terms of the irrigation amount,ammonium in leachate was responsible for the actual inhibition of leachate.The extent of inhibitory effect mainly depended on its ammonium concentration.The suppression of the predominant methaneconsuming bacteria,type Ⅰ MOB,was responsible for the decreased methane oxidation activity by ammonium inhibition.Methaneconsuming bacteria responded diversely in abundance to ammonium.The abundance of type Ⅰ MOB decreased by fivefold; type Ⅱ MOB showed stimulation response of fivefold magnification upon the first addition but lessened to be lower than the original level after the second addition; the amount of AOB was stimulated to increase for 20-30 times gradually.Accumulated nitrate from nitrification strengthened the ammonium inhibition on type Ⅰ and type Ⅱ MOB,as a result,repetitive irrigation was unfavorable for methane oxidation.

  9. 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

    -passive biocover system was constructed at the AV Miljø landfill. The biocover is fed by landfill gas pumped out of three leachate wells. An innovative gas distribution system was used to overcome the often observed overloaded hot spot areas resulting from uneven gas distribution to the active methane oxidation...

  10. Greenhouse gas reduction by recovery and utilization of landfill methane and CO{sub 2} technical and market feasibility study, Boului Landfill, Bucharest, Romania. Final report, September 30, 1997--September 19, 1998

    Energy Technology Data Exchange (ETDEWEB)

    Cook, W.J.; Brown, W.R.; Siwajek, L. [Acrion Technologies, Inc., Cleveland, OH (United States); Sanders, W.I. [Power Management Corp., Bellevue, WA (United States); Botgros, I. [Petrodesign, SA, Bucharest (Romania)

    1998-09-01

    The project is a landfill gas to energy project rated at about 4 megawatts (electric) at startup, increasing to 8 megawatts over time. The project site is Boului Landfill, near Bucharest, Romania. The project improves regional air quality, reduces emission of greenhouse gases, controls and utilizes landfill methane, and supplies electric power to the local grid. The technical and economic feasibility of pre-treating Boului landfill gas with Acrion`s new landfill gas cleanup technology prior to combustion for power production us attractive. Acrion`s gas treatment provides several benefits to the currently structured electric generation project: (1) increase energy density of landfill gas from about 500 Btu/ft{sup 3} to about 750 Btu/ft{sup 3}; (2) remove contaminants from landfill gas to prolong engine life and reduce maintenance;; (3) recover carbon dioxide from landfill gas for Romanian markets; and (4) reduce emission of greenhouse gases methane and carbon dioxide. Greenhouse gas emissions reduction attributable to successful implementation of the landfill gas to electric project, with commercial liquid CO{sub 2} recovery, is estimated to be 53 million metric tons of CO{sub 2} equivalent of its 15 year life.

  11. Use of gas push-pull tests for the measurement of methane oxidation in different landfill cover soils.

    Science.gov (United States)

    Streese-Kleeberg, Jan; Rachor, Ingke; Gebert, Julia; Stegmann, Rainer

    2011-05-01

    In order to optimise methane oxidation in landfill cover soils, it is important to be able to accurately quantify the amount of methane oxidised. This research considers the gas push-pull test (GPPT) as a possible method to quantify oxidation rates in situ. During a GPPT, a gas mixture consisting of one or more reactive gases (e.g., CH(4), O(2)) and one or more conservative tracers (e.g., argon), is injected into the soil. Following this, the mixture of injected gas and soil air is extracted from the same location and periodically sampled. The kinetic parameters for the biological oxidation taking place in the soil can be derived from the differences in the breakthrough curves. The original method of Urmann et al. (2005) was optimised for application in landfill cover soils and modified to reduce the analytical effort required. Optimised parameters included the flow rate during the injection phase and the duration of the experiment. 50 GPPTs have been conducted at different landfills in Germany during different seasons. Generally, methane oxidation rates ranged between 0 and 150 g m(soil air)(-3)h(-1). At one location, rates up to 440 g m(soil air)(-3)h(-1) were measured under particularly favourable conditions. The method is simple in operation and does not require expensive equipment besides standard laboratory gas chromatographs.

  12. Field-scale tracking of active methane-oxidizing communities in a landfill-cover soil reveals spatial and seasonal variability

    NARCIS (Netherlands)

    Henneberger, R.; Chiri, E.; Bodelier, P.L.E.; Frenzel, P.; Luke, C.; Schroth, M.H.

    2015-01-01

    Aerobic methane-oxidizing bacteria (MOB) in soils mitigate methane (CH4) emissions. We assessed spatial and seasonal differences in active MOB communities in a landfill cover soil characterized by highly variable environmental conditions. Field-based measurements of CH4 oxidation activity and stable

  13. Modeling the effects of vegetation on methane oxidation and emissions through soil landfill final covers across different climates.

    Science.gov (United States)

    Abichou, Tarek; Kormi, Tarek; Yuan, Lei; Johnson, Terry; Francisco, Escobar

    2015-02-01

    Plant roots are reported to enhance the aeration of soil by creating secondary macropores which improve the diffusion of oxygen into soil as well as the supply of methane to bacteria. Therefore, methane oxidation can be improved considerably by the soil structuring processes of vegetation, along with the increase of organic biomass in the soil associated with plant roots. This study consisted of using a numerical model that combines flow of water and heat with gas transport and oxidation in soils, to simulate methane emission and oxidation through simulated vegetated and non-vegetated landfill covers under different climatic conditions. Different simulations were performed using different methane loading flux (5-200 g m(-2) d(-1)) as the bottom boundary. The lowest modeled surface emissions were always obtained with vegetated soil covers for all simulated climates. The largest differences in simulated surface emissions between the vegetated and non-vegetated scenarios occur during the growing season. Higher average yearly percent oxidation was obtained in simulations with vegetated soil covers as compared to non-vegetated scenario. The modeled effects of vegetation on methane surface emissions and percent oxidation were attributed to two separate mechanisms: (1) increase in methane oxidation associated with the change of the physical properties of the upper vegetative layer and (2) increase in organic matter associated with vegetated soil layers. Finally, correlations between percent oxidation and methane loading into simulated vegetated and non-vegetated covers were proposed to allow decision makers to compare vegetated versus non-vegetated soil landfill covers. These results were obtained using a modeling study with several simplifying assumptions that do not capture the complexities of vegetated soils under field conditions.

  14. Evaluation of simultaneous biodegradation of methane and toluene in landfill covers.

    Science.gov (United States)

    Su, Yao; Zhang, Xuan; Wei, Xiao-Meng; Kong, Jiao-Yan; Xia, Fang-Fang; Li, Wei; He, Ruo

    2014-06-15

    The biodegradation of CH4 and toluene in landfill cover soil (LCS) and waste biocover soil (WBS) was investigated with a serial toluene concentration in the headspace of landfill cover microcosms in this study. Compared with the LCS sample, the higher CH4 oxidation activity and toluene-degrading capacity occurred in the WBS sample. The co-existence of toluene in landfill gas would positively or negatively affect CH4 oxidation, mainly depending on the toluene concentrations and exposure time. The nearly complete inhibition of toluene on CH4 oxidation was observed in the WBS sample at the toluene concentration of ∼ 80,000 mg m(-3), which was about 10 times higher than that in the LCS sample. The toluene degradation rates in both landfill covers fitted well with the Michaelis-Menten model. These findings showed that WBS was a good alternative landfill cover material to simultaneously mitigate emissions of CH4 and toluene from landfills to the atmosphere.

  15. FUEL CELL OPERATION ON LANDFILL GAS AT PENROSE POWER STATION

    Science.gov (United States)

    This demonstration test successfully demonstrated operation of a commercial phosphoric acid fuel cell (FC) on landfill gas (LG) at the Penrose Power Station in Sun Valley, CA. Demonstration output included operation up to 137 kW; 37.1% efficiency at 120 kW; exceptionally low sec...

  16. Microbial methane oxidation as a means of treating residual emissions during passive landfill venting; Mikrobielle Methanoxidation zur Behandlung von Rest-Emissionen bei der passiven Deponieentgasung

    Energy Technology Data Exchange (ETDEWEB)

    Gebert, J.; Groengroeft, A. [Hamburg Univ. (Germany). Inst. fuer Bodenkunde

    2005-07-01

    Microbial oxidation of methane in biofilters provides a way of treating residual or lean gas emissions from landfills whose methane content and quantities no longer meet the minimum requirements for gas utilisation or flaring. In this process methane is oxidised by methanotropic bacteria in the presence of atmospheric oxygen. This yields carbon dioxide, which is less hazardous on account of its nonflammability and lower global warming potential. This contribution describes the methane degradation performance and performance governing factors of a biofilter which was exposed to a passive gas flow and observed over a period of two years.

  17. Pretreated Landfill Gas Conversion Process via a Catalytic Membrane Reactor for Renewable Combined Fuel Cell-Power Generation

    Directory of Open Access Journals (Sweden)

    Zoe Ziaka

    2013-01-01

    Full Text Available A new landfill gas-based reforming catalytic processing system for the conversion of gaseous hydrocarbons, such as incoming methane to hydrogen and carbon oxide mixtures, is described and analyzed. The exit synthesis gas (syn-gas is fed to power effectively high-temperature fuel cells such as SOFC types for combined efficient electricity generation. The current research work is also referred on the description and design aspects of permreactors (permeable reformers carrying the same type of landfill gas-reforming reactions. Membrane reactors is a new technology that can be applied efficiently in such systems. Membrane reactors seem to perform better than the nonmembrane traditional reactors. The aim of this research includes turnkey system and process development for the landfill-based power generation and fuel cell industries. Also, a discussion of the efficient utilization of landfill and waste type resources for combined green-type/renewable power generation with increased processing capacity and efficiency via fuel cell systems is taking place. Moreover, pollution reduction is an additional design consideration in the current catalytic processors fuel cell cycles.

  18. 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.

  19. Estimating national landfill methane emissions: an application of the 2006 Intergovernmental Panel on Climate Change Waste Model in Panama.

    Science.gov (United States)

    Weitz, Melissa; Coburn, Jeffrey B; Salinas, Edgar

    2008-05-01

    This paper estimates national methane emissions from solid waste disposal sites in Panama over the time period 1990-2020 using both the 2006 Intergovernmental Panel on Climate Change (IPCC) Waste Model spreadsheet and the default emissions estimate approach presented in the 1996 IPCC Good Practice Guidelines. The IPCC Waste Model has the ability to calculate emissions from a variety of solid waste disposal site types, taking into account country- or region-specific waste composition and climate information, and can be used with a limited amount of data. Countries with detailed data can also run the model with country-specific values. The paper discusses methane emissions from solid waste disposal; explains the differences between the two methodologies in terms of data needs, assumptions, and results; describes solid waste disposal circumstances in Panama; and presents the results of this analysis. It also demonstrates the Waste Model's ability to incorporate landfill gas recovery data and to make projections. The former default method methane emissions estimates are 25 Gg in 1994, and range from 23.1 Gg in 1990 to a projected 37.5 Gg in 2020. The Waste Model estimates are 26.7 Gg in 1994, ranging from 24.6 Gg in 1990 to 41.6 Gg in 2020. Emissions estimates for Panama produced by the new model were, on average, 8% higher than estimates produced by the former default methodology. The increased estimate can be attributed to the inclusion of all solid waste disposal in Panama (as opposed to only disposal in managed landfills), but the increase was offset somewhat by the different default factors and regional waste values between the 1996 and 2006 IPCC guidelines, and the use of the first-order decay model with a time delay for waste degradation in the IPCC Waste Model.

  20. [Uncertainty analysis for evaluating methane emissions from municipal solid waste landfill in Beijing].

    Science.gov (United States)

    Chen, Cao-Cao; Liu, Chun-Lan; Li, Zheng; Wang, Hai-Hua; Zhang, Yan; Wang, Lu

    2012-01-01

    In order to improve the accurate evaluation of CH4 emissions from municipal solid waste landfill in Beijing, FOD-model and Monte Carlo method were conducted. Based on local data, national data and experts' experience, the uncertainty of FOD-model and parameters' sensitivity analysis were identified. And we quantified effect of various parameters on model output. The results showed that 95% probability distribution range of CH4 emission from landfill was (11.8-19.76) x 10(4) t x a(-1) in Beijing. The mean value was 15.58 x 10(4)t x a(-1) with uncertainty range of -24.26% - 26.83%. Among all the parameters MCF (after 2000) showed the greatest impact on landfill CH4 emission in 2008, and its contribution to the uncertainty of emission result was 41.4%. This research can improve the assessment accuracy and quality on CH4 emission from municipal solid waste landfill in Beijing, as providing scientific basis to improve the landfill greenhouse gas inventory and data collection.

  1. A logistic model for the prediction of the influence of water on the solid waste methanization in landfills.

    Science.gov (United States)

    Pommier, S; Chenu, D; Quintard, M; Lefebvre, X

    2007-06-15

    This article deals with the impact of water content of solid waste on biogas production kinetics in landfills. This impact has been proved in the laboratory thanks to anaerobic biodegradation experiments on paper/cardboard waste samples. A strong dependence with the moisture level was observed for both kinetic rates and maximum methane production. In this article, a logistic model is proposed to simulate the biogas production rate. It is chosen as simple as possible in order to allow for a correct identification of the model parameters given the experimental data available. The moisture dependency is introduced through a linear weighing of the biomass specific growth rate and of the amount of accessible organic substrate. It is directly linked to physical properties of the waste: the holding capacity and the minimal moisture level allowing the presence of free water.

  2. Field-scale tracking of active methane-oxidizing communities in a landfill cover soil reveals spatial and seasonal variability.

    Science.gov (United States)

    Henneberger, Ruth; Chiri, Eleonora; Bodelier, Paul E L; Frenzel, Peter; Lüke, Claudia; Schroth, Martin H

    2015-05-01

    Aerobic methane-oxidizing bacteria (MOB) in soils mitigate methane (CH4 ) emissions. We assessed spatial and seasonal differences in active MOB communities in a landfill cover soil characterized by highly variable environmental conditions. Field-based measurements of CH4 oxidation activity and stable-isotope probing of polar lipid-derived fatty acids (PLFA-SIP) were complemented by microarray analysis of pmoA genes and transcripts, linking diversity and function at the field scale. In situ CH4 oxidation rates varied between sites and were generally one order of magnitude lower in winter compared with summer. Results from PLFA-SIP and pmoA transcripts were largely congruent, revealing distinct spatial and seasonal clustering. Overall, active MOB communities were highly diverse. Type Ia MOB, specifically Methylomonas and Methylobacter, were key drivers for CH4 oxidation, particularly at a high-activity site. Type II MOB were mainly active at a site showing substantial fluctuations in CH4 loading and soil moisture content. Notably, Upland Soil Cluster-gamma-related pmoA transcripts were also detected, indicating concurrent oxidation of atmospheric CH4 . Spatial separation was less distinct in winter, with Methylobacter and uncultured MOB mediating CH4 oxidation. We propose that high diversity of active MOB communities in this soil is promoted by high variability in environmental conditions, facilitating substantial removal of CH4 generated in the waste body.

  3. Spatial patterns of methane oxidation and methanotrophic diversity in landfill cover soils of southern China.

    Science.gov (United States)

    Chi, Zi-Fang; Lu, Wen-Jing; Wang, Hong-Tao

    2015-04-01

    Aerobic CH4 oxidation is an important CH4 sink in landfills. To investigate the distribution and community diversity of methanotrophs and link with soil characteristics and operational parameters (e.g., concentrations of O2, CH4), cover soil samples were collected at different locations and depths from the Mengzi semi-aerobic landfill (SAL) in Yunnan Province of southern China. Specific PCR followed by denaturing gradient gel electrophoresis and realtime PCR were used to examine methanotrophs in the landfill cover soils. The results showed that different locations did harbor distinct methanotroph communities. Methanotrophs were more abundant in areas near the venting pipes because of the higher O2 concentrations. The depth of 20-25 cm, where the ratio of the CH4 to O2 was within the range from 1.3 to 8.6, was more conducive to the growth of CH4-oxidizing bacteria. Type II methanotrophs dominated in all samples compared with Type I methanotrophs, as evidenced by the high ratio of Type II to Type I methanotrophic copy numbers (from 1.76 to 11.60). The total copy numbers of methanotrophs detected were similar to other ecosystems, although the CH4 concentration was much higher in SAL cover soil. Methylobacter and Methylocystis were the most abundant Type I and Type II methanotrophs genera, respectively, in the Mengzi SAL. The results suggested that SALs could provide a special environment with both high concentrations of CH4 and O2 for methanotrophs, especially around the vertical venting pipes.

  4. Assessment of methane production from shredder waste in landfills: The influence of temperature, moisture and metals

    DEFF Research Database (Denmark)

    Fathi Aghdam, Ehsan; Scheutz, Charlotte; Kjeldsen, Peter

    2017-01-01

    In this study, methane (CH4) production rates from shredder waste (SW) were determined by incubation of waste samples over a period of 230days under different operating conditions, and first-order decay kinetic constants (k-values) were calculated. SW and sterilized SW were incubated under...

  5. Biodegradation of Methane and Halocarbons in Simulated Landfill Biocover Systems Containing Compost Materials

    DEFF Research Database (Denmark)

    Scheutz, Charlotte; Pedersen, Gitte Bukh; Costa, G.

    2009-01-01

    The attenuation potential of methane (CH4) and of selected volatile organic Compounds (VOCs) was compared in four types of compost materials using dynamic flow column experiments over a period of 255 d. Garden waste compost mixed with wood chips showed the highest steady-state CH4 oxidation rate ...

  6. Evaluation of aerated biofilter systems for microbial methane oxidation of poor landfill gas.

    Science.gov (United States)

    Haubrichs, R; Widmann, R

    2006-01-01

    In the long-term, landfills are producing landfill gas (LFG) with low calorific values. Therefore, the utilization of LFG in combined heat and power plants (CHP) is limited to a certain period of time. A feasible method for LFG treatment is microbial CH(4) oxidation. Different materials were tested in actively aerated lab-scale bio-filter systems with a volume of 0.167 m(3). The required oxygen for the microbial CH(4) oxidation was provided through perforated probes, which distributed ambient air into the filter material. Three air input levels were installed along the height of the filter, each of them adjusted to a particular flow rate. During the tests, stable degradation rates of around 28 g/(m(3) h) in a fine-grained compost material were observed at a CH(4) inlet concentration of 30% over a period of 148 days. Compared with passive (not aerated) tests, the CH(4) oxidation rate increased by a factor of 5.5. Therefore, the enhancement of active aeration on the microbial CH(4) oxidation was confirmed. At a O(2)/CH(4) ratio of 2.5, nearly 100% of the CH(4) load was decomposed. By lowering the ratio from 2.5 to 2, the efficiency fell to values from 88% to 92%. By varying the distribution to the three air input levels, the CH(4) oxidation process was spread more evenly over the filter volume.

  7. 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.

  8. Assessment of methane emission and oxidation at Air Hitam Landfill site cover soil in wet tropical climate.

    Science.gov (United States)

    Abushammala, Mohammed F M; Basri, Noor Ezlin Ahmad; Elfithri, Rahmah

    2013-12-01

    Methane (CH₄) emissions and oxidation were measured at the Air Hitam sanitary landfill in Malaysia and were modeled using the Intergovernmental Panel on Climate Change waste model to estimate the CH₄ generation rate constant, k. The emissions were measured at several locations using a fabricated static flux chamber. A combination of gas concentrations in soil profiles and surface CH₄ and carbon dioxide (CO₂) emissions at four monitoring locations were used to estimate the CH₄ oxidation capacity. The temporal variations in CH₄ and CO₂ emissions were also investigated in this study. Geospatial means using point kriging and inverse distance weight (IDW), as well as arithmetic and geometric means, were used to estimate total CH₄ emissions. The point kriging, IDW, and arithmetic means were almost identical and were two times higher than the geometric mean. The CH₄ emission geospatial means estimated using the kriging and IDW methods were 30.81 and 30.49 gm(−2) day(−1), respectively. The total CH₄ emissions from the studied area were 53.8 kg day(−1). The mean of the CH₄ oxidation capacity was 27.5 %. The estimated value of k is 0.138 year(−1). Special consideration must be given to the CH₄ oxidation in the wet tropical climate for enhancing CH₄ emission reduction.

  9. Initial results of detected methane emissions from landfills in the Los Angeles Basin during the COMEX campaign by the Methane Airborne MAPper (MAMAP) instrument and a greenhouse gas in-situ analyser

    Science.gov (United States)

    Krautwurst, Sven; Gerilowski, Konstantin; Kolyer, Richard; Jonsson, Haflidi; Krings, Thomas; Horstjann, Markus; Leifer, Ira; Vigil, Sam; Buchwitz, Michael; Schüttemeyer, Dirk; Fladeland, Matthew M.; Burrows, John P.; Bovensmann, Heinrich

    2015-04-01

    Methane (CH4) is the second most important anthropogenic greenhouse gas beside carbon dioxide (CO2). Significant contributors to the global methane budget are fugitive emissions from landfills. Due to the growing world population, it is expected that the amount of waste and, therefore, waste disposal sites will increase in number and size in parts of the world, often adjacent growing megacities. Besides bottom-up modelling, a variety of ground based methods (e.g., flux chambers, trace gases, radial plume mapping, etc.) have been used to estimate (top-down) these fugitive emissions. Because landfills usually are large, sometimes with significant topographic relief, vary temporally, and leak/emit heterogeneously across their surface area, assessing total emission strength by ground-based techniques is often difficult. In this work, we show how airborne based remote sensing measurements of the column-averaged dry air mole fraction of CH4 can be utilized to estimate fugitive emissions from landfills in an urban environment by a mass balance approach. Subsequently, these emission rates are compared to airborne in-situ horizontal cross section measurements of CH4 taken within the planetary boundary layer (PBL) upwind and downwind of the landfill at different altitudes immediately after the remote sensing measurements were finished. Additional necessary parameters (e.g., wind direction, wind speed, aerosols, dew point temperature, etc.) for the data inversion are provided by a standard instrumentation suite for atmospheric measurements aboard the aircraft, and nearby ground-based weather stations. These measurements were part of the CO2 and Methane EXperiment (COMEX), which was executed during the summer 2014 in California and was co-funded by the European Space Agency (ESA) and the National Aeronautics and Space Administration (NASA). The remote sensing measurements were taken by the Methane Airborne MAPper (MAMAP) developed and operated by the University of Bremen and

  10. TESTING OF FUEL CELLS TO RECOVER ENERGY FROM LANDFILL GAS: GROTON LANDFILL

    Science.gov (United States)

    The report summarizes the results of follow-on tests following a four-phase EPA program. The environmental impact of widespread use of this concept would be a significant reduction of global warming gas emissions (methane and carbon dioxide). The follow-on testing, conducted by N...

  11. Observations from using models to fit the gas production of varying volume test cells and landfills.

    Science.gov (United States)

    Lamborn, Julia

    2012-12-01

    Landfill operators are looking for more accurate models to predict waste degradation and landfill gas production. The simple microbial growth and decay models, whilst being easy to use, have been shown to be inaccurate. Many of the newer and more complex (component) models are highly parameter hungry and many of the required parameters have not been collected or measured at full-scale landfills. This paper compares the results of using different models (LANDGEM, HBM, and two Monod models developed by the author) to fit the gas production of laboratory scale, field test cell and full-scale landfills and discusses some observations that can be made regarding the scalability of gas generation rates. The comparison of these results show that the fast degradation rate that occurs at laboratory scale is not replicated at field-test cell and full-scale landfills. At small scale, all the models predict a slower rate of gas generation than actually occurs. At field test cell and full-scale a number of models predict a faster gas generation than actually occurs. Areas for future work have been identified, which include investigations into the capture efficiency of gas extraction systems and into the parameter sensitivity and identification of the critical parameters for field-test cell and full-scale landfill predication.

  12. Microbial reduction of methane emissions. Subproject 1: Development of a biofilter system for the degradation of methane, odours and trace gases for actively vented landfills. Subproject 2: Development of a biofilter system for the degradation of methane, odours and trace gases for passively vented landfills. Subproject 3: Planning, development and realisation of medium and large scale biofilter plants at active and passive gas drainage systems. Final report; Mikrobielle Verminderung von Methanemissionen. Teilvorhaben 1: Entwicklung eines Biofilterverfahrens zum Abbau von Methan, Geruechen und Spurengasen bei der aktiven Deponieentgasung. Teilvorhaben 2: Entwicklung eines Biofilterverfahrens zum Abbau von Methan, Geruechen und Spurengasen bei der passiven Deponieentgasung. Teilvorhaben 3: Planung, Entwicklung und Realisation halb- und grosstechnischer Biofilteranlagen an aktiven und passiven Entgasungssystemen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Stegmann, R.; Streese, J.; Dammann, Bernd; Gebert, J.; Groengroeft, A.; Miehlich, G.; Schulze, H.; Berndt, M.

    2003-07-01

    Old landfills may emit considerable amounts of methane, carbon dioxide and trace gases. However, gas flow rate and methane content are usually too low for energetic utilization or flaring of the landfill gas. Microbial degradation is considered an alternative treatment for the reduction of methane emissions from those sites. The project aimed in the investigation of the suitability of actively vented biofilters for this purpose and the collection of operational experience and dimensioning data for large scale applications of the process. Different experimental plants were operated in laboratory scale (filter volume: 60 L) and container scale (filter volume: 4 m{sup 3}). The laboratory scale plant was operated with synthetic methane, whereas the container scale plant was set up at an old landfill and operated with real landfill gas. For each plant, the gas was diluted with ambient air prior to feeding into the closed biofilters, thus sufficient oxygen for methane oxidation was present throughout the filter material. At first, fine-grained compost as biofilter material was investigated. A biofilter unit of 15 m{sup 3} size containing porous clay pellets as filter material was integrated into the recultivation layer of a Hamburg harbour sludge landfill. The parameters of landfill gas emission as well as the abiotic parameters of biofilter operation were monitored by a high-resolution automatic data collection system and gas distribution and gas emissions via the biofilter surface measured regularly. In addition, microbiological laboratory studies and studies concerning physical questions of biofilter operations were conducted. (orig.)

  13. Superficial methane emissions from a landfill in Merida, Yucatan, Mexico; Emisiones superficiales de metano en un relleno sanitario en Merida, Yucatan, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Sauri-Riancho, Maria Rosa [Universidad Autonoma de Yucatan, Yucatan (Mexico)]. E-mail: sriancho@uady.mx; Stentiford, Edward I. [University of Leeds (UK)]. E-mail: e.i.stentiford@leeds.ac.uk; Gamboa-Marrufo, Mauricio; Reza-Bacelis, Gabriela; Cahuich-Poot, Nayla; Mendez-Novelo, Roger [Universidad Autonoma de Yucatan, Yucatan (Mexico)]. E-mails: gmarrufo@uady.mx; gabriela.reza@proactiva.com.mx; nayre63@hotmail.com; mnovelo@uady.mx

    2013-07-15

    On worldwide scale, one of the most important anthropogenic methane sources is landfill disposal for solid wastes. The main goal of this work was to quantify methane emissions at one landfill built in Merida, Mexico. This site had venting wells by which a passive control for biogas movement was exerted. At the venting wells, methane concentrations were measured monthly during a 6 months period. Methane surface emission rate was estimated with the close chamber technique. Obtained results indicated that there are both spatial and seasonal variations in biogas composition. The average methane value during the monitoring period was 21.9% (12.7 to 32.5 V/V) and the surface flow rate was in the range of 0 to 6,004 g CH{sub 4} m-2 d-1, with an average value of 1,480 g CH{sub 4} m-2 d-1, which is a high value in respect to these reported in publications. [Spanish] Entre las fuentes antropogenicas mas importantes de metano a escala mundial se encuentra la disposicion final de los residuos solidos. El objetivo de este trabajo fue cuantificar las emisiones de metano provenientes de un relleno sanitario en Merida, Mexico, en el que el movimiento del biogas se controlaba pasivamente utilizando pozos de venteo. Las concentraciones de metano se midieron mensualmente en los pozos de venteo del sitio a lo largo de un periodo de 6 meses. La tasa de emision superficial de metano se determino utilizando la tecnica de camara cerrada. Los resultados indicaron que existen variaciones considerables tanto espaciales como estacionales de la composicion del biogas proveniente de los pozos de venteo con un promedio de concentracion de metano en el sitio, durante todo el periodo de monitoreo, de 21.9% (12.7 a 32.5 V/V). Los flujos superficiales de gas medidos en diversos puntos a lo largo de la superficie del relleno sanitario tuvieron un promedio de 1,480 g CH{sub 4} m-2 d-1, lo que se considero un valor muy alto cuando se comparo con la informacion hallada en la literatura. El intervalo

  14. DEMONSTRATION OF FUEL CELLS TO RECOVER ENERGY FROM LANDFILL GAS - PHASE I FINAL REPORT: CONCEPTUAL STUDY

    Science.gov (United States)

    The report discusses results of a conceptual design, cost, and evaluation study of energy recovery from landfill gas using a commercial phosphoric acid fuel cell power plant. The conceptual design of the fuel cell energy recovery system is described, and its economic and environm...

  15. Landfill leachate treatment in assisted landfill bioreactor

    Institute of Scientific and Technical Information of China (English)

    HE Pin-jing; QU Xian; SHAO Li-ming; LEE Duu-jong

    2006-01-01

    Landfill is the major disposal route of municipal solid waste(MSW) in most Asian countries. Leachate from landfill presents a strong wastewater that needs intensive treatment before discharge. Direct recycling was proposed as an effective alternative for leachate treatment by taking the landfill as a bioreactor. This process was proved not only considerably reducing the pollution potential of leachate, but also enhancing organic degradation in the landfill. However, as this paper shows, although direct leachate recycling was effective in landfilled MSW with low food waste fraction (3.5%, w/w), it failed in MSW containing 54% food waste, as normally noted in Asian countries. The initial acid stuck would inhibit methanogenesis to build up, hence strong leachate was yielded from landfill to threaten the quality of receiving water body. We demonstrated the feasibility to use an assisted bioreactor landfill, with a well-decomposed refuse layer as ex-situ anaerobic digester to reducing COD loading in leachate. By doing so, the refuse in simulated landfill column (2.3 m high) could be stabilized in 30 weeks while the COD in leachate reduced by 95%(61000 mg/L to 3000 mg/L). Meanwhile, the biogas production was considerably enhanced, signaling by the much greater amount and much higher methane content in the biogas.

  16. Research Progress on Methanotrophic Bacteria in Landfills and the Reduction of Methane Emission%垃圾填埋场甲烷氧化菌及甲烷减排的研究进展

    Institute of Scientific and Technical Information of China (English)

    王晓琳; 曹爱新; 周传斌; 赵恺凝; 赵国柱

    2016-01-01

    As the main source of anthropogenic methane emission,landfills globally produce 35-69 Tg methane per year. The technology of reducing the methane emission in landfills has become a hot topic at present. Methanotrophic bacteria decomposing methane are the important biological collection to reduce atmospheric methane emissions,which is of significance in keeping the balance of the methane concentration in the atmosphere. Starting from the taxonomy and characteristics of methanotrophic bacteria,and the mechanism of its oxidizing methane, we summarized the latest research progress on the methods of studying diversity,factors affecting the activities of methanotrophic bacteria in landfills,and applications of them in the biological reduction of methane emission. Based on the prior researches,the issues in current studies of methanotrophic bacteria are also discussed. We propose comprehensive measures of utilizing the complex microbial agents of methanotrophic bacteria in landfills,providing a new thought in the research and application of reducing methane emission in landfills.%垃圾填埋场是全球最重要的人为甲烷排放源之一,其全球年甲烷释放量为35-69 Tg,垃圾填埋场甲烷减排是目前全球温室气体研究的热点。甲烷氧化菌能够氧化分解甲烷,作为减少大气甲烷排放的重要生物汇,对保持大气中甲烷浓度的平衡具有重要意义。从甲烷氧化菌的类型及其特征、甲烷氧化机理着手,介绍了多样性研究方法、填埋场中甲烷氧化菌的活性影响因素及甲烷生物减排应用等最新研究进展。在综述前人研究的基础上,探讨了目前研究的不足,提出了利用甲烷氧化菌复合微生物菌剂等综合处理措施,旨为垃圾填埋场甲烷减排的研究和应用提供新的思路。

  17. Methane emissions from sanitary landfills in Italy. Evaluation and forecasting; Le emissioni di metano dalle discariche di rifiuti in Italia: stima e scenari futuri

    Energy Technology Data Exchange (ETDEWEB)

    Colombari, F.; De Lauretis, R.; De Stefanis, P.; Gaudioso, D. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Ambiente

    1998-07-01

    The report estimates the methane emissions from landfills by three different methodologies derived from IPCC experiences. A detailed evaluation of solid waste production (MSW) composition is shown in order to update results obtained from old researches. Finally it shows a prediction of MSW production from 1996 to 2011 in different scenarios related to MSW management strategies. [Italian] Il rapporto analizza la stima della quantita' di metano generato dalle discariche di rifiuti utilizzando tre differenti metodologie di calcolo, derivanti dalle conoscenze scientifiche dell'IPCC, dopo aver approfondito la composizione dei rifiuti. Riporta infine per il periodo 1996-2011, la stima della produzione e dello smaltimento dei rifiuti e la predisposizione di diversi scenari futuri di emissione del metano, relativi a differenti scelte all'interno del sistema di gestione dei rifiuti.

  18. ELECTRIC POWER GENERATION USING A PHOSPHORIC ACID FUEL CELL ON A MUNICIPAL SOLID WASTE LANDFILL GAS STREAM

    Science.gov (United States)

    The report gives results of tests to verify the performance of a landfill gas pretreatment unit (GPU) and a phorsphoric acid fuel cell system. The complete system removes contaminants from landfill gas and produces electricity for on-site use or connection to an electric grid. Th...

  19. DEMONSTRATION OF FUEL CELLS TO RECOVER ENERGY FROM LANDFILL GAS: PHASE II. PRETREATMENT SYSTEM PERFORMANCE MEASUREMENT

    Science.gov (United States)

    The report describes Phase II of a demonstration of the utilization of commercial phosphoric acid fuel cells to recover energy from landfill gas. This phase consisted primarily of the construction and testing of a Gas Pretreatment Unit (GPU) whose function is to remove those impu...

  20. PRACTICE REVIEW OF FIVE BIOREACTOR/RECIRCULATION LANDFILLS

    Science.gov (United States)

    Six bioreactor landfills were analyzed to provide a perspective of current practice and technical issues that differentiate bioreactor landfills from conventional landfills. Five of the bioreactor landfills were anaerobic and one was aerated. In one case, nearly identical cells e...

  1. Seasonal greenhouse gas emissions (methane, carbon dioxide, nitrous oxide) from engineered landfills: daily, intermediate, and final California cover soils.

    Science.gov (United States)

    Bogner, Jean E; Spokas, Kurt A; Chanton, Jeffrey P

    2011-01-01

    Compared with natural ecosystems and managed agricultural systems, engineered landfills represent a highly managed soil system for which there has been no systematic quantification of emissions from coexisting daily, intermediate, and final cover materials. We quantified the seasonal variability of CH, CO, and NO emissions from fresh refuse (no cover) and daily, intermediate, and final cover materials at northern and southern California landfill sites with engineered gas extraction systems. Fresh refuse fluxes (g m d [± SD]) averaged CH 0.053 (± 0.03), CO 135 (± 117), and NO 0.063 (± 0.059). Average CH emissions across all cover types and wet/dry seasons ranged over more than four orders of magnitude (types, including both final covers, averaging 200 cm) cover materials, below which methanogenesis was well established, the variability in gaseous fluxes was attributable to cover thickness, texture, density, and seasonally variable soil moisture and temperature at suboptimal conditions for CH oxidation. Thin daily covers (30 cm local soil) and fresh refuse generally had the highest CO and NO fluxes, indicating rapid onset of aerobic and semi-aerobic processes in recently buried refuse, with rates similar to soil ecosystems and windrow composting of organic waste. This study has emphasized the need for more systematic field quantification of seasonal emissions from multiple types of engineered covers.

  2. Methane production in anaerobic digestion of organic waste from Recife (Brazil landfill: evaluation in refuse of diferent ages

    Directory of Open Access Journals (Sweden)

    W. N. Schirmer

    2014-06-01

    Full Text Available This work focuses on monitoring the generation of biogas by biochemical methane potential (BMP assays, commonly used to assess anaerobic biodegradability of solid and liquid wastes under controlled conditions. The experiment employed 5 g of substrate of both refuses (fresh and one-year-old wastes, digested with 250 mL of inoculum in 1 L flasks as bioreactors (all of them in triplicate, operating under batch conditions at ± 35 ºC. Despite the difference of age of both refuses evaluated, there was no significant differences in volume (near 1800 mL and composition (55% methane of biogas generated in 80 days of incubation under mesophilic conditions. The important parameters of both refuses (such as moisture content, volatile solids and chemical oxygen demand also showed very similar initial values.

  3. Landfill gas management facilities design guidelines

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-03-15

    In British Columbia, municipal solid waste landfills generate over 1000 tonnes of methane per year; landfill gas management facilities are required to improve the environmental performance of solid waste landfills. The aim of this document, developed by the British Columbia Ministry of the Environment, is to provide guidance for the design, installation, and operation of landfill gas management facilities to address odor and pollutant emissions issues and also address health and safety issues. A review of technical experience and best practices in landfill gas management facilities was carried out, as was as a review of existing regulations related to landfill gas management all over the world. This paper provides useful information to landfill owners, operators, and other professionals for the design of landfill gas management facilities which meet the requirements of landfill gas management regulations.

  4. Liquid balance monitoring inside conventional, Retrofit, and bio-reactor landfill cells

    Energy Technology Data Exchange (ETDEWEB)

    Abichou, Tarek, E-mail: abichou@eng.fsu.edu [Department of Civil and Environmental Engineering, Florida State University, 2525 Pottsdamer Street, Tallahassee, FL 32311 (United States); Barlaz, Morton A. [Department of Civil, Construction, and Environmental Engineering, North Carolina State University, Raleigh, NC 27695 (United States); Green, Roger; Hater, Gary [Waste Management Inc., Cincinnati, OH 45211 (United States)

    2013-10-15

    Highlights: • The Retrofit, Control, and As-Built cells received 48, 14, and 213 L Mg{sup −1} (liters of liquids per metric ton of waste). • The leachate collection system yielded 60, 57 and 198 L Mg{sup −1} from the Retrofit, Control, and As-Built cells. • The head on liner in all cells was below regulatory limits. • Measured moisture content of the waste samples was consistent with that calculated from accumulated liquid by balance. • The in-place saturated hydraulic conductivity of the MSW was calculated to be in the range of 10{sup −8} to 10{sup −7} m s{sup −1}. - Abstract: The Outer Loop landfill bioreactor (OLLB) in Louisville, KY, USA has been the site of a study to evaluate long-term bioreactor performance at a full-scale operational landfill. Three types of landfill units were studied including a conventional landfill (Control cell), a new landfill area that had an air addition and recirculation piping network installed as waste was being placed (As-Built cell), and a conventional landfill that was modified to allow for liquids recirculation (Retrofit cell). During the monitoring period, the Retrofit, Control, and As-Built cells received 48, 14, and 213 L Mg{sup −1} (liters of liquids per metric ton of waste), respectively. The leachate collection system yielded 60, 57 and 198 L Mg{sup −1} from the Retrofit, Control, and As-Built cells, respectively. The head on liner in all cells was below regulatory limits. In the Control and As-Built cells, leachate head on liner decreased once waste placement stopped. The measured moisture content of the waste samples was consistent with that calculated from the estimate of accumulated liquid by the liquid balance. Additionally, measurements on excavated solid waste samples revealed large spatial variability in waste moisture content. The degree of saturation in the Control cells decreased from 85% to 75%. The degree of saturation increased from 82% to 83% due to liquids addition in the Retrofit

  5. Modelling of landfill gas adsorption with bottom ash for utilization of renewable energy

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Chen

    2011-10-06

    Energy crisis, environment pollution and climate change are the serious challenges to people worldwide. In the 21st century, human being is trend to research new technology of renewable energy, so as to slow down global warming and develop society in an environmentally sustainable method. Landfill gas, produced by biodegradable municipal solid waste in landfill, is a renewable energy source. In this work, landfill gas utilization for energy generation is introduced. Landfill gas is able to produce hydrogen by steam reforming reactions. There is a steam reformer equipment in the fuel cells system. A sewage plant of Cologne in Germany has run the Phosphoric Acid Fuel Cells power station with biogas for more than 50,000 hours successfully. Landfill gas thus may be used as fuel for electricity generation via fuel cells system. For the purpose of explaining the possibility of landfill gas utilization via fuel cells, the thermodynamics of landfill gas steam reforming are discussed by simulations. In practice, the methane-riched gas can be obtained by landfill gas purification and upgrading. This work investigate a new method for upgrading-landfill gas adsorption with bottom ash experimentally. Bottom ash is a by-product of municipal solid waste incineration, some of its physical and chemical properties are analysed in this work. The landfill gas adsorption experimental data show bottom ash can be used as a potential adsorbent for landfill gas adsorption to remove CO{sub 2}. In addition, the alkalinity of bottom ash eluate can be reduced in these adsorption processes. Therefore, the interactions between landfill gas and bottom ash can be explained by series reactions accordingly. Furthermore, a conceptual model involving landfill gas adsorption with bottom ash is developed. In this thesis, the parameters of landfill gas adsorption equilibrium equations can be obtained by fitting experimental data. On the other hand, these functions can be deduced with theoretical approach

  6. Simulation model for oxygen consumption flux and prediction of methane oxidation in landfill cover soil%覆盖层氧气消耗通量模型及甲烷氧化能力预测

    Institute of Scientific and Technical Information of China (English)

    邢志林; 赵天涛; 陈新安; 车轮; 张丽杰; 全学军

    2015-01-01

    填埋场覆盖层生物气扩散规律和甲烷氧化能力的评估是甲烷减排研究的重要组成部分。以数值模拟方法分析了氧气在覆盖层中的扩散规律,得到了指数方程形式的氧气扩散模型(R2范围0.8941~0.9975);通过检测有机碳和甲烷浓度变化进一步考察了模拟覆盖层不同深度的甲烷氧化能力,证实了在0.05~0.25 m范围内甲烷氧化活性最高;以Fick定律和轴向扩散模型推导了模拟覆盖层中氧气消耗通量模型,该模型计算得到的氧气消耗通量与覆盖层中微生物甲烷氧化经验方程相比无显著差异;结合以上模型推演出覆盖层甲烷消耗通量模型,与实际检测值相比,预测结果理想(R2=0.9983)。该成果可为揭示填埋场覆盖层生物气扩散规律、强化甲烷氧化能力以及预测甲烷排放提供新的思路和理论依据。%Diffusion process of biogas and evaluation of methane oxidation in landfill cover soil are important parts of research on methane emission. Diffusion process of oxygen in landfill cover soil was analyzed by simulation, and an oxygen diffusion model fitted by exponential equation (0.8941methane oxidation in different landfill cover depths was also investigated by analyzing organic carbon and monitoring methane concentration. The most intensive methane oxidation occurred at the layer of 0.05—0.25 m. An oxygen consumption flux model in landfill cover was derived on the basis of Fick’s law and axial dispersion model. There was no significant difference between fitted values by oxygen consumption flux model and derived values by empirical equation of biological methane oxidation. Based on the above model, a methane consumption flux model was derived finally, and the prediction was consistent with detection. These results provided new ideas and theoretical basis for revealing biogas diffusion process in landfill cover soil

  7. Trends for Methane Oxidation at Solid Oxide Fuel Cell Conditions

    DEFF Research Database (Denmark)

    Kleis, Jesper; Jones, Glenn; Abild-Pedersen, Frank;

    2009-01-01

    the Ni surfaces to other metals of interest. This allows the reactivity over the different metals to be understood in terms of two reactivity descriptors, namely, the carbon and oxygen adsorption energies. By combining a simple free-energy analysis with microkinetic modeling, activity landscapes of anode......First-principles calculations are used to predict a plausible reaction pathway for the methane oxidation reaction. In turn, this pathway is used to obtain trends in methane oxidation activity at solid oxide fuel cell (SOFC) anode materials. Reaction energetics and barriers for the elementary...

  8. Landfill Mining of Shredder Residues

    DEFF Research Database (Denmark)

    Hansen, Jette Bjerre; Hyks, Jiri; Shabeer Ahmed, Nassera

    In Denmark, shredder residues (SR) are classified as hazardous waste and until January 2012 the all SR were landfilled. It is estimated that more than 1.8 million tons of SR have been landfilled in mono cells. This paper describes investigations conducted at two Danish landfills. SR were excavated...

  9. Landfilling: Hydrology

    DEFF Research Database (Denmark)

    Kjeldsen, Peter; Beaven, R.

    2011-01-01

    Landfill hydrology deals with the presence and movement of water through a landfill. The main objective in landfill hydrology is usually to predict leachate generation, but the presence and movement of water in a landfill also affect the degradation of the waste, the leaching of pollutants...... and the geotechnical stability of the fill. Understanding landfill hydrology is thus important for many aspects of landfill, in particular siting, design and operation. The objective of this chapter is to give a basic understanding of the hydrology of landfills, and to present ways to estimate leachate quantities......-circuiting. In the final section different existing hydrological models for landfills are presented with a special focus on the HELP model. This model is the most widely used tool for the prediction of leachate quantities in landfills, and for the sizing of leachate control and management infrastructure....

  10. The implementation of artificial neural networks to model methane oxidation in landfill soil covers[Includes the CSCE forum on professional practice and career development : 1. international engineering mechanics and materials specialty conference : 1. international/3. coastal, estuarine and offshore engineering specialty conference : 2. international/8. construction specialty conference

    Energy Technology Data Exchange (ETDEWEB)

    Szeto, A.; Albanna, M.; Warith, M. [Ottawa Univ., ON (Canada). Faculty of Civil and Environmental Engineering

    2009-07-01

    The disposal of solid waste significantly contributes to the total anthropogenic emissions of methane (CH{sub 4}), a greenhouse gas that negatively affects climate change. The oxidation of methane in landfill bio-covers takes place through the use of methanotrophic bacteria which provides a sink for methane. The rate at which methane is biologically oxidized depends on several parameters. This study provided a better understanding of the oxidation of methane in landfill soil covers through modeling methane oxidation with artificial neural networks (ANNs). An ANN was trained and tested to model methane oxidation in various batch scale systems for 3 types of soils. Input data consisted of temperature, moisture content, soil composition and the nutrient content added to the system. Model results were in good agreement with experimental results reported by other researchers. It was concluded that the use of ANNs to model methane oxidation in batch scale bio-covers can address the large number of complicated physical and biochemical processes that occur within the landfill bio-cover. 10 refs., 7 tabs., 5 figs.

  11. Comparison between controlled landfill reactor and conditioned landfill bioreactor

    Institute of Scientific and Technical Information of China (English)

    LUO Feng; CHEN Wan-zhi; SONG Fu-zhong; LI Xiao-peng; ZHANG Guo-qing

    2004-01-01

    Bioreactor landfills allow a more active landfill management that recognizes the biological, chemical and physical processes involved in a landfill environment. The results of laboratory-scale simulators of landfill reactors treating municipal solid wastes were studied, the effect of solid waste size, leachate recirculation, nutrient balance, pH value, moisture content and temperature on the rate of municipal solid waste(MSW) biodegradation were determined, and it indicated the optimum pH value, moisture content and temperature can used to decompose MSW. The results of waste biodegradation were compared with that of the simulators of the leachate-recirculated landfill and conservative sanitary landfill. In the control experiment the antitheses of a decreasing trend of the organic load, measured as biological oxygen demand and chemical oxygen demand, was shown, and heavy metals concentration was observed. An obvious enhancement of effective disposal from simulator of conservative sanitary landfill(CSL), to that of leachate-recirculated landfill(LRL) and to that of conditioned bioreactor landfill(CBL) would be noted, through displaying the compared results of solid waste settlement, heavy metal concentration in leachate, methane production rate, biogas composition, BOD and COD as well as their ratio.

  12. Results of coalbed-methane drilling, Meadowfill Landfill, Harrison County, West Virginia: Chapter G.4 in Coal and petroleum resources in the Appalachian basin: distribution, geologic framework, and geochemical character

    Science.gov (United States)

    Ruppert, Leslie F.; Trippi, Michael H.; Fedorko, Nick; Grady, William C.; Eble, Cortland F.; Schuller, William A.; Ruppert, Leslie F.; Ryder, Robert T.

    2014-01-01

    The U.S. Environmental Protection Agency funded drilling of a borehole (39.33889°N., 80.26542°W.) to evaluate the potential of enhanced coalbed-methane production from unminable Pennsylvanian coal beds at the Meadowfill Landfill near Bridgeport, Harrison County, W. Va. The drilling commenced on June 17, 2004, and was completed on July 1, 2004. The total depth of the borehole was 1,081 feet (ft) and contained 1,053.95 ft of Pennsylvanian coal-bearing strata, and 27.05 ft of Mississippian strata.

  13. Microbial electrolysis cells for production of methane from CO2: long-term performance and perspectives

    NARCIS (Netherlands)

    Eerten-Jansen, van M.C.A.A.; Heijne, ter A.; Buisman, C.J.N.; Hamelers, H.V.M.

    2012-01-01

    A methane-producing microbial electrolysis cell (MEC) is a technology to convert CO2 into methane, using electricity as an energy source and microorganisms as the catalyst. A methane-producing MEC provides the possibility to increase the fuel yield per hectare of land area, when the CO2 produced in

  14. Fermentation pre-treatment of landfill leachate for enhanced electron recovery in a microbial electrolysis cell.

    Science.gov (United States)

    Mahmoud, Mohamed; Parameswaran, Prathap; Torres, César I; Rittmann, Bruce E

    2014-01-01

    Pre-fermentation of poorly biodegradable landfill leachate (BOD5/COD ratio of 0.32) was evaluated for enhanced current density (j), Coulombic efficiency (CE), Coulombic recovery (CR), and removal of organics (BOD5 and COD) in a microbial electrolysis cell (MEC). During fermentation, the complex organic matter in the leachate was transformed to simple volatile fatty acids, particularly succinate and acetate in batch tests, but mostly acetate in semi-continuous fermentation. Carbohydrate had the highest degree of fermentation, followed by protein and lipids. j, CE, CR, and BOD5 removal were much greater for an MEC fed with fermented leachate (23 A/m(3) or 16 mA/m(2), 68%, 17.3%, and 83%, respectively) compared to raw leachate (2.5 A/m(3) or 1.7 mA/m(2), 56%, 2.1%, and 5.6%, respectively). All differences support the value of pre-fermentation before an MEC for stabilization of BOD5 and enhanced electron recovery as current when treating a recalcitrant wastewater like landfill leachate.

  15. The co-oxidation of methane and dichloromethane in landfill bio-cover[Includes the CSCE forum on professional practice and career development : 1. international engineering mechanics and materials specialty conference : 1. international/3. coastal, estuarine and offshore engineering specialty conference : 2. international/8. construction specialty conference

    Energy Technology Data Exchange (ETDEWEB)

    Dagher, E.; Albanna, M.; Fernandes, L.; Warith, M. [Ottawa Univ., ON (Canada). Faculty of Engineering

    2009-07-01

    Solid waste landfills are responsible for 13 per cent of the annual global anthropogenic methane (CH{sub 4}) emissions. Landfill bio-cover systems using methanotrophic bacteria to oxidize CH{sub 4} to carbon dioxide (CO{sub 2}) and water (H{sub 2}O) is a cost effective solution for the attenuation of these fugitive greenhouse gases (GHGs). This study analyzed the affect of dichloromethane (DCM), a volatile organic compound (VOC), on the rate of methane oxidation at several environmental conditions. Compost from Trail Road, a municipal landfill in Ottawa, was used in batch experiments. Gas chromatography was used to measure the concentrations of CH{sub 4} in the absence of DCM, and under varying DCM concentrations and atmospheric temperatures. The oxidation of DCM by the methanotrophs in the presence as well as absence of CH{sub 4} was also observed, and their oxidation rates determined. The study showed that the presence of DCM plays a very significant role on the oxidative capacity of CH{sub 4} under closed conditions on a laboratory scale. The study also showed that it will be important to restrict the type of waste that can be dumped in landfills. Controlling the industrial waste of non-methane organic carbon (NMOC) dumped into municipal landfills is crucial if CH{sub 4} is to be oxidized by a bio-cover. 15 refs., 4 figs.

  16. Bioreactor landfill

    Institute of Scientific and Technical Information of China (English)

    WANG Hao; XING Kai; Anthony Adzomani

    2004-01-01

    Following the population expansion, there is a growing threat brought by municipal solid waste (MSW) against environment and human health. Sanitary landfill is the most important method of MSW disposal in China. In contrast to the conventional landfill, this paper introduces a new technique named bioreactor landfill (BL). Mechanisms, operation conditions as well as the advantages and disadvantages of BL are also discussed in this paper.

  17. Comparison Of Four Landfill Gas Models Using Data From Four Danish Landfills

    DEFF Research Database (Denmark)

    Mønster, Jacob G.; Mou, Zishen; Kjeldsen, Peter

    2011-01-01

    , and to compare the four Danish landfill sites. The results show that three of the models generally give similar methane generation output. Only the LandGem model seems to give a much higher methane generation for Danish waste data, most likely due to a low organic fraction. Interpretation of the waste data......Data about type and quantity of waste disposed in four Danish landfills was collected and used on four different landfill gas generation models. This was done to compare the output data in order to evaluate the performance of the four landfill gas models when used on Danish waste types...... and the categorization of the waste play an important role in the methane prediction and combining the model predictions with whole site methane measurements would therefore be advised....

  18. 联合型生物反应器填埋场厌氧单元产甲烷规律研究%Study on Methane Generation Regulation in Anaerobic-semiaerobic Bioreactor Anaerobic Landfill

    Institute of Scientific and Technical Information of China (English)

    宋豪娟; 刘丹; 韩智勇; 王宁

    2013-01-01

    基于模拟实验,研究新型厌氧型生物反应器(ANBL)-准好氧矿化垃圾联合型生物反应器(SAABR)厌氧单元产气速率、产气CH4含量以及累计产CH4量的变化规律.实验证明,由于回灌复氧后的渗滤液甲烷菌的活性受到抑制,AN-SABL中的厌氧填埋单元的产气受到了抑制,但较高的回灌频率使得渗滤液与微生物的接触机会增多,利于垃圾产气;综合分析产气CH4含量、渗滤液COD和渗滤液pH值,在此判断3个ANBL CH4发酵阶段分别为705~820,690~ 800和660~740 d,该阶段产气φ(CH4)最大值分别为78.6%,74.1%和71.5%.建立了ANBL累计产CH4量的指数增长模型,对生物反应器CH.的收集和利用有重要意义.%Alstract:Based on the experimental simulation device,the regulation of the gas production,content of methane and cumulative methane production in the anaerobic-semiaerobic bioreactor landfill were studied.It was proved that,methane germ of the activity was repressed because of leachate recirculation to infuse to reply oxygen,and gas production in the ANSABL was repressed,but higher leachate recirculation frequency improved the contact opportunity of leachate and microorganism,then benefit gas production; comprehensively analyzed the gas methane content,leachate COD and leachate pH,this research judged three ANBL methane ferments stage were 705 ~ 820 d,690 ~ 800 d and 660 ~ 740 d,that stage the biggest content of methane is 78.6%,74.1% and 71.5%.The index number growth model of the ANBL cumulative methane was built up,which was important to collections and exploitation of bioreactor methane.

  19. Methane oxidation kinetics of bio-cover sewage sludge modified by coal ash for landfill%垃圾填埋场覆盖材料改性污泥的甲烷氧化动力学

    Institute of Scientific and Technical Information of China (English)

    王丹; 赵玲; 尹平河; 肖娟宜; 黄思明

    2012-01-01

    在实验室模拟条件下,以粉煤灰改性污泥为垃圾填埋场生物覆盖材料,分析了初始甲烷浓度、初始氧气浓度对甲烷氧化效率的影响,并测定了甲烷氧化动力学方程及动力学参数,旨在为材料实际工程应用提供理论依据.结果表明:初始CH4、O2浓度制约生物覆盖材料的甲烷氧化效率,初始CH4、O2浓度越高,材料甲烷氧化能力越强;甲烷氧化过程符合2级动力学方程-dV(CH4)/dt=kV(CH4)V(O2);利用Michaelis-Menten模型得出覆盖层材料的最大氧化速率Vmax为2.54 μmol g-1h-1,半速常数Km为0.49 μmol.%In this study, laboratory-scale experiments were carried out to examine the effects of initial methane and oxygen contents on methane oxidation efficiency in landfill bio-cover sewage sludge, and the kinetic equation and corresponding parameters were also determined, aiming to provide scientific basis for the practical engineering application. The results showed that the methane and oxygen contents strongly affected the methane oxidation efficiency. The higher methane and oxygen contents resulted in stronger methane oxidation efficiency. The kinetics of methane oxidation was - dV( CH4)/di = kV{ CH4 ) V( 02) , which fit the second-order reaction. As calculated from Michaelis-Menten equation, the largest methane oxidation rate ( Kmax ) was 2. 54 μmol g ‐ 1h‐ 1, and the half saturation constant ( Km ) was found at 0. 49 μmol.

  20. Yolo County's Accelerated Anaerobic and Aerobic Composting (Full-Scale Controlled Landfill Bioreactor) Project

    Science.gov (United States)

    Yazdani, R.; Kieffer, J.; Akau, H.; Augenstein, D.

    2002-12-01

    elimination of methane production and acceleration of waste decomposition. In the first phase of this project a 12-acre module that contains a 9.5-acre anaerobic cell and a 2.5-acre aerobic cell has been constructed and filled with over 220,000 tons of municipal solid waste. Water and leachate addition began in April 2002 and to date less than 200,000 gallons of liquid has been added to the 3.5-acre anaerobic cell. The waste filling phase of the aerobic cell was completed in June of 2002 and a 12-inches soil cover and 12-inches of greenwaste compost cover was placed on top of the cell. A vacuum will be applied to the piping within the waste to draw air through the landfill. Instrumentations have been installed to monitor the following parameters: waste temperature, moisture, leachate volumes, leachate hydraulic head over the primary liner, leachate composition, gas volumes and composition. A supervisory Control and Data Acquisition (SCADA) system has been installed to monitor and control the operation of the bioreactor cells. Waste samples were taken from each cell for laboratory testing in early June 2002.

  1. Project identification for methane reduction options

    Energy Technology Data Exchange (ETDEWEB)

    Kerr, T.

    1996-12-31

    This paper discusses efforts directed at reduction in emission of methane to the atmosphere. Methane is a potent greenhouse gas, which on a 20 year timeframe may present a similar problem to carbon dioxide. In addition, methane causes additional problems in the form of smog and its longer atmospheric lifetime. The author discusses strategies for reducing methane emission from several major sources. This includes landfill methane recovery, coalbed methane recovery, livestock methane reduction - in the form of ruminant methane reduction and manure methane recovery. The author presents examples of projects which have implemented these ideas, the economics of the projects, and additional gains which come from the projects.

  2. Landfills as a biorefinery to produce biomass and capture biogas.

    Science.gov (United States)

    Bolan, N S; Thangarajan, R; Seshadri, B; Jena, U; Das, K C; Wang, H; Naidu, R

    2013-05-01

    While landfilling provides a simple and economic means of waste disposal, it causes environmental impacts including leachate generation and greenhouse gas (GHG) emissions. With the introduction of gas recovery systems, landfills provide a potential source of methane (CH4) as a fuel source. Increasingly revegetation is practiced on traditionally managed landfill sites to mitigate environmental degradation, which also provides a source of biomass for energy production. Combustion of landfill gas for energy production contributes to GHG emission reduction mainly by preventing the release of CH4 into the atmosphere. Biomass from landfill sites can be converted to bioenergy through various processes including pyrolysis, liquefaction and gasification. This review provides a comprehensive overview on the role of landfills as a biorefinery site by focusing on the potential volumes of CH4 and biomass produced from landfills, the various methods of biomass energy conversion, and the opportunities and limitations of energy capture from landfills.

  3. Feasibility of atmospheric methane removal using methanotrophic biotrickling filters

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Sukhwan; Carey, Jeffrey N.; Semrau, Jeremy D. [Michigan Univ., Ann Arbor, MI (United States). Dept. of Civil and Environmental Engineering

    2009-07-15

    Methane is a potent greenhouse gas with a global warming potential {proportional_to}23 times that of carbon dioxide. Here, we describe the modeling of a biotrickling filtration system composed of methane-consuming bacteria, i.e., methanotrophs, to assess the utility of these systems in removing methane from the atmosphere. Model results indicate that assuming the global average atmospheric concentration of methane, 1.7 ppmv, methane removal is ineffective using these methanotrophic biofilters as the methane concentration is too low to enable cell survival. If the concentration is increased to 500-6,000 ppmv, however, similar to that found above landfills and in concentrated animal feeding operations (factory farms), 4.98-35.7 tons of methane can be removed per biofilter per year assuming biotrickling filters of typical size (3.66 m in diameter and 11.5 m in height). Using reported ranges of capital, operational, and maintenance costs, the cost of the equivalent ton of CO{sub 2} removal using these systems is $90-$910 ($2,070-$20,900 per ton of methane), depending on the influent concentration of methane and if heating is required. The use of methanotrophic biofilters for controlling methane emissions is technically feasible and, provided that either the costs of biofilter construction and operation are reduced or the value of CO{sub 2} credits is increased, can also be economically attractive. (orig.)

  4. Evolution on qualities of leachate and landfill gas in the semi-aerobic landfill

    Institute of Scientific and Technical Information of China (English)

    HUANG Qifei; YANG Yufei; PANG Xiangrui; WANG Qi

    2008-01-01

    To study the characteristics of stabilization in semi-aerobic landfill, large-scale simulated landfill was constructed based on the semi-aerobic landfill theory. Consequently, the concentrations of chemical oxygen demand (COD), ammonia nitrogen, and nitrite nitrogen, and the pH value in leachate, as well as the component contents of landfill gas composition (methane, carbon dioxide, and oxygen) in landfill were regularly monitored for 52 weeks. The results showed that COD and ammonia concentrations declined rapidly and did not show the accumulating rule like anaerobic landfill, and remained at about 300 and 100 mg/L, respectively, after 48 weeks. Meanwhile, the descending rate reached 98.9% and 96.9%, respectively. Nitrate concentration increased rapidly after 24 weeks and fluctuated between 220-280 mg/L after 43 weeks. The pH values were below 7 during the first 8 weeks and after that leachates appeared to be alkaline. Carbon dioxide was the main composition in landfill gas and its concentration remained at a high level through the whole stabilization process. The average contents of carbon dioxide, oxygen, and methane varied between 19 vol.%-28 vol.%, 2 vol.%-8 vol.%, and 5 vol.%-13 vol.%, respectively. A relative equilibrium was reached after 48 weeks. The highest temperature in the landfill chamber could amount to 75.8 degrees centigrade.

  5. Steam Methane Reformation Testing for Air-Independent Solid Oxide Fuel Cell Systems

    Science.gov (United States)

    Mwara, Kamwana N.

    2015-01-01

    Recently, NASA has been looking into utilizing landers that can be propelled by LOX-CH (sub 4), to be used for long duration missions. Using landers that utilize such propellants, also provides the opportunity to use solid oxide fuel cells as a power option, especially since they are able to process methane into a reactant through fuel reformation. One type of reformation, called steam methane reformation, is a process to reform methane into a hydrogen-rich product by reacting methane and steam (fuel cell exhaust) over a catalyst. A steam methane reformation system could potentially use the fuel cell's own exhaust to create a reactant stream that is hydrogen-rich, and requires less internal reforming of the incoming methane. Also, steam reformation may hold some advantages over other types of reforming, such as partial oxidation (PROX) reformation. Steam reformation does not require oxygen, while up to 25 percent can be lost in PROX reformation due to unusable CO (sub 2) reformation. NASA's Johnson Space Center has conducted various phases of steam methane reformation testing, as a viable solution for in-space reformation. This has included using two different types of catalysts, developing a custom reformer, and optimizing the test system to find the optimal performance parameters and operating conditions.

  6. Study on Production of Hydrogen from Methane for Proton Exchange Membrane Fuel Cell

    Institute of Scientific and Technical Information of China (English)

    宋正昶; 李传统

    2001-01-01

    The hydrogen production from methane for proton exchange membrane fuel cell (PEMFC) was studied experimentally. The conversion rate of methane under different steam-carbon ratios, the effect of the different excess air ratios on the constituents of the gas produced, the permeability of hydrogen under different pressure differences, and the effect of different system pressure on the reaction enthalpy of hydrogen were obtained. The results lay the basis for the production of hydrogen applicable to PEMFC, moreover, provide a new way for the comprehensive utilization of the coal bed methane.

  7. 垃圾渗滤液发酵产氢和产甲烷特性研究%Bio-production of hydrogen and methane from landfill leachate by anaerobic fermentation

    Institute of Scientific and Technical Information of China (English)

    徐乔根; 傅木星; 苏泱洲; 汪敏; 潘建国

    2012-01-01

    The characteristics of hydrogen and methane production from landfill leachate by anaerobic fermentation at 37 ℃ and pH 7. 0 was studied. The experimental results suggested that during the process of leachate anaerobic fermentation,the maximum cumulative production of hydrogen and methane was 24. 33,91. 95 mL (counted by per gram of COD) respectively; there was a lag phase a in the process of hydrogen production,while the methane production process appear no lag phase. Large amount of volatile organic acids and ethanol were found in the ultimate liquid product in hydrogen production process with the concentration of ethanol,acetate and butyrate was 487. 23,1 175. 21, 1 225. 78 mg/L respectively. Compared with hydrogen production process,ethanol,acetate and butyrate production of methane production process was relatively low,the concentration of was 256. 38,106. 73,107. 42 mg/L respectively. The ultimate mixture of hydrogen production process was strong acidic, the pH value was 4. 21. While, in methane production process,the ultimate mixture was close to neutral, the pH value was 6. 32. The removal rate of COD in methane production process was 41. 78% , which was higher than that of hydrogen production process (32. 14%). This might be the acetate in ultimate mixture of hydrogen production process could be utilized by methanogenesis and further be biodegrade.%以实际垃圾渗滤液作为厌氧发酵基质,研究了初始pH为7.0、中温(37℃)条件下的发酵产氢、产甲烷特性.结果表明,利用垃圾渗滤液作为基质发酵产氢或甲烷时,氢气的最大累积产量为24.33 mL(以每克COD计,下同),甲烷的最大累积产量为91.59 mL,产氢发酵在初期存在明显的迟滞期,但是产甲烷发酵不存在明显迟滞期;产氢发酵的液相末端产物中含有大量的挥发性有机酸和乙醇,乙醇、乙酸、丁酸质量浓度分别为487.23、1175.21、1225.78 mg/L,相比产氢发酵,产甲烷发酵的液相末端产物中乙

  8. Measurement of representative landfill gas migration samples at landfill perimeters: a case study

    OpenAIRE

    Kiernan, Breda M.; Beirne, Stephen; Fay, Cormac; Diamond, Dermot

    2009-01-01

    This paper describes the development of a fully integrated autonomous system based on existing infrared sensing technology capable of monitoring landfill gas migration (specifically carbon dioxide and methane) at landfill sites. Sampling using the described system was validated against the industry standard, GA2000 Plus hand held device, manufactured by Geotechnical Instruments Inc. As a consequence of repeated sampling during validation experiments, fluctuations in the gas mixtures became ap...

  9. Landfill leachate sludge use as soil additive prior and after electrocoagulation treatment: A cytological assessment using CHO-k1 cells.

    Science.gov (United States)

    Morozesk, M; Bonomo, M M; Rocha, L D; Duarte, I D; Zanezi, E R L; Jesus, H C; Fernandes, M N; Matsumoto, S T

    2016-09-01

    Electrocoagulation has recently attracted attention as a potential technique for treating toxic effluents due to its versatility and environmental compatibility, generating a residue chemically suitable to be used as a soil additive. In the present study, landfill leachate sludge hazardous effects were investigated prior and after electrocoagulation process using in vitro assays with the mammalian cells CHO-k1. An integrated strategy for risk assessment was used to correctly estimate the possible adverse landfill leachate sludge effects on human health and ecosystem. Electrocoagulation process proved to be an effective treatment due to possibility to improve effluent adverse characteristics and produce sludge with potential to be used as soil additive. Despite low cytoxicity, the residue presented genotoxic and mutagenic effects, indicating a capacity to induce genetic damages, probably due to induction of polyploidization process in cells. The observed effects demand an improvement of waste management methods for reduce negative risks of landfill leachate sludge application.

  10. Feasibility study: utilization of landfill gas for a vehicle fuel system, Rossman's landfill, Clackamas County, Oregon

    Energy Technology Data Exchange (ETDEWEB)

    None

    1981-01-01

    In 1978, a landfill operator in Oregon became interested in the technical and economic feasibility of recovering the methane generated in the landfill for the refueling of vehicles. DOE awarded a grant for a site-specific feasibility study of this concept. This study investigated the expected methane yield and the development of a conceptual gas-gathering system; gas processing, compressing, and storage systems; and methane-fueled vehicle systems. Cost estimates were made for each area of study. The results of the study are presented. Reasoning that gasoline prices will continue to rise and that approximately 18,000 vehicles in the US have been converted to operate on methane, a project is proposed to use this landfill as a demonstration site to produce and process methane and to fuel a fleet (50 to 400) vehicles with the gas produced in order to obtain performance and economic data on the systems used from gas collection through vehicle operation. (LCL)

  11. Catalytic reduction of NO by methane using a Pt/C/polybenzimidazole/Pt/C fuel cell

    DEFF Research Database (Denmark)

    Petrushina, Irina; Cleemann, Lars Nilausen; Refshauge, Rasmus;

    2007-01-01

    The catalytic NO reduction by methane was studied using a (NO,CH4,Ar),Pt|polybenzimidazole(PBI)–H3PO4|Pt,(H2,Ar) fuel cell at 135 and 165°C. It has been found that, without any reducing agent (like CH4), NO can be electrochemically reduced in the (NO, Ar), Pt/C|PBI–H3PO4|Pt/C, (H2,Ar) fuel cell...... with participation of H+ or electrochemically produced hydrogen. When added, methane partially suppresses the electrochemical reduction of NO. Methane outlet concentration monitoring has shown the CH4 participation in the chemical catalytic reduction, i.e., methane co-adsorption with NO inhibited the electrochemical...... NO reduction and introduced a dominant chemical path of the NO reduction. The products of the NO reduction with methane were N2, C2H4, and water. The catalytic NO reduction by methane was promoted when the catalyst was negatively polarized (−0.2 V). Repeated negative polarization of the catalyst increased...

  12. Methane Steam Reforming over an Ni-YSZ Solid Oxide Fuel Cell Anode in Stack Configuration

    DEFF Research Database (Denmark)

    Mogensen, David; Grunwaldt, Jan-Dierk; Hendriksen, Peter Vang;

    2014-01-01

    The kinetics of catalytic steam reforming of methane over an Ni-YSZ anode of a solid oxide fuel cell (SOFC) have been investigated with the cell placed in a stack configuration. In order to decrease the degree of conversion, a single cell stack with reduced area was used. Measurements were...... performed in the temperature range 600-800 degrees C and the partial pressures of all reactants and products were varied. The obtained rates could be well fitted with a power law expression (r proportional to P-CH4(0.7)). A simple model is presented which is capable of predicting the methane conversion...

  13. Landfills, Landfills, Published in 2003, Taylor County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Landfills dataset, was produced all or in part from Published Reports/Deeds information as of 2003. It is described as 'Landfills'. Data by this publisher are...

  14. Landfilling: Environmental Issues

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Manfredi, Simone; Kjeldsen, Peter

    2011-01-01

    , the extent and quality of the technical environmental protection measures introduced, the daily operation and the timescale. This chapter describes the main potential environmental impacts from landfills. The modern landfill is able to avoid most of these impacts. However, in the planning and design...... of landfills it is important to understand the potential environmental impacts, which must be avoided. The emissions of landfill gas and leachate causing most of the environmental risks are described in detail in the chapters addressing specific landfill types: Chapter 10.5 (mineral waste landfill), Chapter 10...... to air, soil and water caused by the processes stabilizing the waste in the landfill. The main factors controlling the actual environmental impacts from the landfilling are: the nature and amount of the waste landfilled, the geological and hydrological setting of the landfill, the landfill technology...

  15. Landfilling of waste: accounting of greenhouse gases and global warming contributions

    DEFF Research Database (Denmark)

    Manfredi, Simone; Tonini, Davide; Christensen, Thomas Højlund

    2009-01-01

    Accounting of greenhouse gas (GHG) emissions from waste landfilling is summarized with the focus on processes and technical data for a number of different landfilling technologies: open dump (which was included as the worst-case-scenario), conventional landfills with flares and with energy recovery......, and landfills receiving low-organic-carbon waste. The results showed that direct emissions of GHG from the landfill systems (primarily dispersive release of methane) are the major contributions to the GHG accounting, up to about 1000 kg CO2-eq. tonne —1 for the open dump, 300 kg CO2-eq. tonne —1...... for conventional landfilling of mixed waste and 70 kg CO2-eq. tonne—1 for low-organic-carbon waste landfills. The load caused by indirect, upstream emissions from provision of energy and materials to the landfill was low, here estimated to be up to 16 kg CO2-eq. tonne—1. On the other hand, utilization of landfill...

  16. Biogas generation in landfills. Equilibria, rates and yields

    Energy Technology Data Exchange (ETDEWEB)

    Aakesson, M.

    1997-05-01

    Landfilling in `cells` has become more common in recent years. Different waste streams are guided to different cells, among which the biocell is a landfill designed for biogas production. In this thesis, the dependence of biogas generation on waste composition was investigated. Six 8,000 m{sup 3} test cells, with contents ranging from mainly commercial waste to pure domestic waste and equipped with gas extraction systems and bottom plastic liners, were monitored for seven years. Great emphasis was given to the characterization of conversion processes and governing mechanism in the topics of bio-energetics, kinetics and capacities. A thermodynamic model, in which the oxidations of volatile fatty acids (VFA) (2methane production rates and internal conditions observed during a two year period, demonstrated that high biogas rates corresponded with low VFA levels. To explain the discrepancies between theoretical methane potentials and quantified yields (in this study found to be 150-200 and 40-70 Nm{sup 3}/dry tonne, respectively), the possible nutritional limitation was investigated. Pools and emissions of chemical oxygen demand, N, P and K were quantified. Biomass pools were estimated from methane yields, growth yield coefficients, and bacterial mineral contents. However, results from commercial waste test cells showed that the assimilation of P exceeded the refuse content, which suggests the turnover of microbial biomass and questions the notion of nutritional limitation. In sum, the results showed that the advantages of a reduced content of readily biodegradable material, achieved by guidance or pretreatment, encompass several aspects of the performance. 84 refs, 6 figs, 1 tab

  17. 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...

  18. Gaseous methyl- and inorganic mercury in landfill gas from landfills in Florida, Minnesota, Delaware, and California

    Science.gov (United States)

    Lindberg, S. E.; Southworth, G.; Prestbo, E. M.; Wallschläger, D.; Bogle, M. A.; Price, J.

    2005-01-01

    Municipal waste landfills contain numerous sources of mercury which could be emitted to the atmosphere. Their generation of methane by anaerobic bacteria suggests that landfills may act as bioreactors for methylated mercury compounds. Since our previous study at a single Florida landfill, gaseous inorganic and methylated mercury species have now been identified and quantified in landfill gas at nine additional municipal landfills in several regions of the US. Total gaseous mercury occurs at concentrations in the μg m-3 range, while methylated compounds occur at concentrations in the ng m-3 range at all but one of the landfill sites. Dimethylmercury is the predominant methylated species, at concentrations up to 100 ng m-3, while monomethyl mercury was generally lower. Limited measurements near sites where waste is exposed for processing (e.g. working face, transfer areas) suggest that dimethylmercury is released during these activities as well. Although increasing amounts of landfill gas generated in the US are flared (which should thermally decompose the organic mercury to inorganic mercury), unflared landfill gas is a potentially important anthropogenic source of methylated mercury emissions to the atmosphere.

  19. Ceramic anode catalyst for dry methane type molten carbonate fuel cell

    Science.gov (United States)

    Tagawa, T.; Yanase, A.; Goto, S.; Yamaguchi, M.; Kondo, M.

    Oxide catalyst materials for methane oxidation were examined in order to develop the anode electrode for molten carbonate type fuel cell (MCFC). As a primary selection, oxides such as lanthanum (La 2O 3) and samarium (Sm 2O 3) were selected from screening experiments of TPD, TG and tubular reactor. Composite materials of these oxides with titanium fine powder were assembled into a cell unit for MCFC as the anode electrode. Steady-state activities were observed with these anode electrode materials when hydrogen was used as a fuel. When methane was directly charged to anode as a fuel (dry methane operation), a power generation with steady state was observed on both lanthanum and samarium composites after gradual decrease of open circuit electromotive force (OCV) and closed circuit current (CCI). The steady-state activity held as long as 144 h of continuous operation.

  20. Mobile measurement of methane: plumes, isotopes and inventory verification

    Science.gov (United States)

    Lowry, D.; Zazzeri, G.; Fisher, R. E.; France, J.; Al-Shalaan, A.; Lanoisellé, M.; Nisbet, E. G.

    2015-12-01

    Since 2013 the RHUL group has been identifying methane plumes from major UK sources using a Picarro 2301 coupled to the A0941 mobile module. Once identified the plumes have been sampled by filling Tedlar or Flexfoil bags for later carbon isotopic analysis by high-precision IRMS. This method has ben successfully deployed to isotopically characterize the main anthropogenic methane emitters in the UK (natural gas, coal, landfill, wastewater treatment, cattle; Zazzeri et al., 2015) and during overseas campaigns in eastern Australia (coal, cattle, legacy gas wells) and Kuwait (landfill, wastewater treatment, oil refineries, cattle, camels). This has identified strong similarities of isotopic signature for some sources (landfill, cattle), but large variations for others (natural gas, coal), which must be isotopically resolved at regional scale. Both landfill and natural gas emissions in SE England have tightly-constrained δ13C signatures, averaging -58 ± 3‰ and -36 ± 2‰, respectively, the latter being characteristic of homogenised North Sea gas supply. In contrast, signatures for coal mines in England and Wales fall in a range of 51.2 ± 0.3‰ to 30.9 ± 1.4‰, but can be tightly constrained by region. On a local scale in west London, repeat surveys in the boroughs of Hounslow and Runnymede have been made for comparison with the latest 1x1 km grid UK inventories for 2009 and 2012, which are subdivided by UNECE categories. An excess methane map can be derived for comparison with inventory emissions maps by identifying daily background and binning the excess values from mobile measurements by grid-square. This shows that the spatial distribution of emissions in the UK 2012 inventory is a big improvement on that of 2009. It also suggests that there is an overestimation of emissions from old landfills (closed before 2000 and reliant on a topsoil cap for oxidation), and an underestimation on emissions from currently active landfill cells. Zazzeri, G. et al. (2015

  1. Decoupling of DAMO archaea from DAMO bacteria in a methane-driven microbial fuel cell.

    Science.gov (United States)

    Ding, Jing; Lu, Yong-Ze; Fu, Liang; Ding, Zhao-Wei; Mu, Yang; Cheng, Shuk H; Zeng, Raymond J

    2017-03-01

    Anaerobic oxidation of methane (AOM) contributes significantly to the global methane sink. Previously, studies of anaerobic methanotrophic (ANME) archaea have been limited as they have not been separable from their bacterial partners during the AOM process because of their dependence on the bacteria. A microbial fuel cell (MFC) is a device capable of directly transforming chemical energy to electrical energy via electrochemical reactions involving biochemical pathways. In this study, decoupling of denitrifying anaerobic methane oxidation (DAMO) archaea and DAMO bacteria was investigated in an microbial fuel cell (MFC) using methane as the fuel. The DAMO fuel cell worked successfully but demonstrated weak electrogenic capability with around 25 mV production. After 45 days' enrichment, the sequencing and fluorescence in situ hybridization results showed the DAMO archaea percentage had increased from 26.96% (inoculum) to 65.77% (electrode biofilm), while the DAMO bacteria percentage decreased from 24.39% to 2.07%. Moreover, the amount of ANME-2d had doubled in the electrode biofilm compared with the inoculum. The sequencing results also showed substantial enrichment of the Ignavibacterium and Geobacter genera. The roles of Ignavibacterium and Geobacter in the MFC system need to be further investigated. Nevertheless, these results illustrate that an MFC device may provide a possible approach to separate DAMO archaea from DAMO bacteria.

  2. Artificial sweeteners as potential tracers of municipal landfill leachate.

    Science.gov (United States)

    Roy, James W; Van Stempvoort, Dale R; Bickerton, Greg

    2014-01-01

    Artificial sweeteners are gaining acceptance as tracers of human wastewater in the environment. The 3 artificial sweeteners analyzed in this study were detected in leachate or leachate-impacted groundwater at levels comparable to those of untreated wastewater at 14 of 15 municipal landfill sites tested, including several closed for >50 years. Saccharin was the dominant sweetener in old (pre-1990) landfills, while newer landfills were dominated by saccharin and acesulfame (introduced 2 decades ago; dominant in wastewater). Cyclamate was also detected, but less frequently. A case study at one site illustrates the use of artificial sweeteners to identify a landfill-impacted groundwater plume discharging to a stream. The study results suggest that artificial sweeteners can be useful tracers for current and legacy landfill contamination, with relative abundances of the sweeteners potentially providing diagnostic ability to distinguish different landfills or landfill cells, including crude age-dating, and to distinguish landfill and wastewater sources.

  3. Methane Production in Microbial Reverse-Electrodialysis Methanogenesis Cells (MRMCs) Using Thermolytic Solutions

    KAUST Repository

    Luo, Xi

    2014-08-05

    The utilization of bioelectrochemical systems for methane production has attracted increasing attention, but producing methane in these systems requires additional voltage to overcome large cathode overpotentials. To eliminate the need for electrical grid energy, we constructed a microbial reverse- electrodialysis methanogenesis cell (MRMC) by placing a reverse electrodialysis (RED) stack between an anode with exoelectrogenic microorganisms and a methanogenic biocathode. In the MRMC, renewable salinity gradient energy was converted to electrical energy, thus providing the added potential needed for methane evolution from the cathode. The feasibility of the MRMC was examined using three different cathode materials (stainless steel mesh coated with platinum, SS/Pt; carbon cloth coated with carbon black, CC/CB; or a plain graphite fiber brush, GFB) and a thermolytic solution (ammonium bicarbonate) in the RED stack. A maximum methane yield of 0.60 ± 0.01 mol-CH 4/mol-acetate was obtained using the SS/Pt biocathode, with a Coulombic recovery of 75 ± 2% and energy efficiency of 7.0 ± 0.3%. The CC/CB biocathode MRMC had a lower methane yield of 0.55 ± 0.02 mol-CH4/mol-acetate, which was twice that of the GFB biocathode MRMC. COD removals (89-91%) and Coulombic efficiencies (74-81%) were similar for all cathode materials. Linear sweep voltammetry and electrochemical impedance spectroscopy tests demonstrated that cathodic microorganisms enhanced electron transfer from the cathode compared to abiotic controls. These results show that the MRMC has significant potential for production of nearly pure methane using low-grade waste heat and a source of waste organic matter at the anode. © 2014 American Chemical Society.

  4. Methane production in microbial reverse-electrodialysis methanogenesis cells (MRMCs) using thermolytic solutions.

    Science.gov (United States)

    Luo, Xi; Zhang, Fang; Liu, Jia; Zhang, Xiaoyuan; Huang, Xia; Logan, Bruce E

    2014-01-01

    The utilization of bioelectrochemical systems for methane production has attracted increasing attention, but producing methane in these systems requires additional voltage to overcome large cathode overpotentials. To eliminate the need for electrical grid energy, we constructed a microbial reverse-electrodialysis methanogenesis cell (MRMC) by placing a reverse electrodialysis (RED) stack between an anode with exoelectrogenic microorganisms and a methanogenic biocathode. In the MRMC, renewable salinity gradient energy was converted to electrical energy, thus providing the added potential needed for methane evolution from the cathode. The feasibility of the MRMC was examined using three different cathode materials (stainless steel mesh coated with platinum, SS/Pt; carbon cloth coated with carbon black, CC/CB; or a plain graphite fiber brush, GFB) and a thermolytic solution (ammonium bicarbonate) in the RED stack. A maximum methane yield of 0.60 ± 0.01 mol-CH4/mol-acetate was obtained using the SS/Pt biocathode, with a Coulombic recovery of 75 ± 2% and energy efficiency of 7.0 ± 0.3%. The CC/CB biocathode MRMC had a lower methane yield of 0.55 ± 0.02 mol-CH4/mol-acetate, which was twice that of the GFB biocathode MRMC. COD removals (89-91%) and Coulombic efficiencies (74-81%) were similar for all cathode materials. Linear sweep voltammetry and electrochemical impedance spectroscopy tests demonstrated that cathodic microorganisms enhanced electron transfer from the cathode compared to abiotic controls. These results show that the MRMC has significant potential for production of nearly pure methane using low-grade waste heat and a source of waste organic matter at the anode.

  5. Methane Steam Reforming over an Ni-YSZ Solid Oxide Fuel Cell Anode in Stack Configuration

    Directory of Open Access Journals (Sweden)

    D. Mogensen

    2014-01-01

    Full Text Available The kinetics of catalytic steam reforming of methane over an Ni-YSZ anode of a solid oxide fuel cell (SOFC have been investigated with the cell placed in a stack configuration. In order to decrease the degree of conversion, a single cell stack with reduced area was used. Measurements were performed in the temperature range 600–800°C and the partial pressures of all reactants and products were varied. The obtained rates could be well fitted with a power law expression (r ∝PCH40.7. A simple model is presented which is capable of predicting the methane conversion in a stack configuration from intrinsic kinetics of the anode support material. The predictions are compared with the stack measurements presented here, and good agreement is observed.

  6. Hydrophobic organic chemicals (HOCs) removal from biologically treated landfill leachate by powder-activated carbon (PAC), granular-activated carbon (GAC) and biomimetic fat cell (BFC).

    Science.gov (United States)

    Liyan, Song; Youcai, Zhao; Weimin, Sun; Ziyang, Lou

    2009-04-30

    Biological pretreatment efficiently remove organic matter from landfill leachate, but further removal of refractory hydrophobic organic chemicals (HOCs) is hard even with advanced treatment. In this work, three-stage-aged refuse bioreactor (ARB) efficiently removed chemical oxygen demand (COD) and biochemical oxygen demand (BOD) of fresh leachate produced in Shanghai laogang landfill, from 8603 to 451 mg L(-1) and 1368 to 30 mg L(-1), respectively. In downstream treatment, 3 g L(-1) powder-activated carbon (PAC), granular-activated carbon (GAC) and biomimetic fat cell (BFC) removed 89.2, 73.4 and 81.1% HOCs, but only 24.6, 19.1 and 8.9% COD, respectively. Through the specific HOCs accumulation characteristics of BFC, about 11.2% HOCs with low molecular weight (effluent exhibited a wide molecular weight distribution (34-514,646 Da). These constitutes are derived from both autochthonous and allochthonous matters as well as biological activities.

  7. Recovery of nitrogen and water from landfill leachate by a microbial electrolysis cell-forward osmosis system.

    Science.gov (United States)

    Qin, Mohan; Molitor, Hannah; Brazil, Brian; Novak, John T; He, Zhen

    2016-01-01

    A microbial electrolysis cell (MEC)-forward osmosis (FO) system was previously reported for recovering ammonium and water from synthetic solutions, and here it has been advanced with treating landfill leachate. In the MEC, 65.7±9.1% of ammonium could be recovered in the presence of cathode aeration. Without aeration, the MEC could remove 54.1±10.9% of ammonium from the leachate, but little ammonia was recovered. With 2M NH4HCO3 as the draw solution, the FO process achieved 51% water recovery from the MEC anode effluent in 3.5-h operation, higher than that from the raw leachate. The recovered ammonia was used as a draw solute in the FO for successful water recovery from the treated leachate. Despite the challenges with treating returning solution from the FO, this MEC-FO system has demonstrated the potential for resource recovery from wastes, and provide a new solution for sustainable leachate management.

  8. [Performance of microbial fuel cells with Fe/C catalyst carbon felt air-cathode for treating landfill leachate].

    Science.gov (United States)

    Tang, Yu-Lan; Peng, Man; Yu, Yan; He, Ya-Ting; Fu, Jin-Xiang; Zhao, Yu-Hua

    2012-06-01

    Ferric nitrate/activated carbon powder catalyst was obtained through impregnation and Fe/C catalyst was adsorbed on carbon felt as air cathode electrodes. Effects of activated carbon powder dosage and ferric nitrate concentration on electricity generation of MFC with landfill leachate as fuel were measured. Performances of cathodes obtained at different ferric nitrate concentrations were evaluated by cyclic voltammetry tests. The results showed that with the increase of activated carbon powder dosage or the iron nitrate concentration, MFC produce electrical properties showed a decreasing trend after the first rise. When the activated carbon powder dosage was 1 g and the iron nitrate concentration was 0.25 mol x L(-1), it was proved to be an optimum cell performance for 4199.8 mW x m(-3) output power and 465 omega apparent resistance. Under the optimal ratio rang between ferric nitrate and activated carbon powder, MFC apparent resistance decreased and the power density increased respectively with the increase of catalyst total dosage. The best produce electrical properties of MFC with Fe/C catalyst for 0.25 mol x L(-1) iron nitrate and 1 g activated carbon powder dosage was observed by cyclic voltammetry tests. The output power of MFC and the removal quantity increased with the concentration of inlet and the maximum values were respectively 5478.92 mW x m(-3) and 1505.2 mg x L(-1). the maximum removal rates of COD achieved at 89.1%.

  9. Transport and reaction processes affecting the attenuation of landfill gas in cover soils

    DEFF Research Database (Denmark)

    Molins, S.; Mayer, K.U.; Scheutz, Charlotte

    2008-01-01

    to exopolymeric substance production, may result in reduced methane attenuation due to limited O2-ingress. Copyright © 2008 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.......Methane and trace organic gases produced in landfill waste are partly oxidized in the top 40 cm of landfill cover soils under aerobic conditions. The balance between the oxidation of landfill gases and the ingress of atmospheric oxygen into the soil cover determines the attenuation of emissions...... of methane, chlorofluorocarbons, and hydrochlorofluorocarbons to the atmosphere. This study was conducted to investigate the effect of oxidation reactions on the overall gas transport regime and to evaluate, the contributions of various gas transport processes on methane attenuation in landfill cover soils...

  10. Proposed Expansion of Acme Landfill Operations.

    Science.gov (United States)

    1982-08-01

    decays, it produces bacteria that release gases. Methane develops in phases. Initially, during a phase which can last several days to months, a...90 and 95°F. Another factor which affects landfill gas production is pH. Methanogenic bacteria need a pH near 7.0 to produce optimal amounts of...Los Osos-Millsholm-Los Gatos soil association while the other four sites were located in the Altamont-Diablo-Fontana association. A standard slope

  11. The presence of hydrogenotrophic methanogens in the inoculum improves methane gas production in microbial electrolysis cells.

    KAUST Repository

    Siegert, Michael

    2014-01-01

    High current densities in microbial electrolysis cells (MECs) result from the predominance of various Geobacter species on the anode, but it is not known if archaeal communities similarly converge to one specific genus. MECs were examined here on the basis of maximum methane production and current density relative to the inoculum community structure. We used anaerobic digester (AD) sludge dominated by acetoclastic Methanosaeta, and an anaerobic bog sediment where hydrogenotrophic methanogens were detected. Inoculation using solids to medium ratio of 25% (w/v) resulted in the highest methane production rates (0.27 mL mL(-1) cm(-2), gas volume normalized by liquid volume and cathode projected area) and highest peak current densities (0.5 mA cm(-2)) for the bog sample. Methane production was independent of solid to medium ratio when AD sludge was used as the inoculum. 16S rRNA gene community analysis using pyrosequencing and quantitative PCR confirmed the convergence of Archaea to Methanobacterium and Methanobrevibacter, and of Bacteria to Geobacter, despite their absence in AD sludge. Combined with other studies, these findings suggest that Archaea of the hydrogenotrophic genera Methanobacterium and Methanobrevibacter are the most important microorganisms for methane production in MECs and that their presence in the inoculum improves the performance.

  12. Stabilisation of composite LSFCO-CGO based anodes for methane oxidation in solid oxide fuel cells

    Science.gov (United States)

    Sin, A.; Kopnin, E.; Dubitsky, Y.; Zaopo, A.; Aricò, A. S.; Gullo, L. R.; Rosa, D. La; Antonucci, V.

    A La 0.6Sr 0.4Fe 0.8Co 0.2O 3-Ce 0.8Gd 0.2O 1.9 (LSFCO-CGO) composite anode material was investigated for the direct electrochemical oxidation of methane in intermediate temperature solid oxide fuel cells (IT-SOFCs). A maximum power density of 0.17 W cm -2 at 800 °C was obtained with a methane-fed ceria electrolyte-supported SOFC. A progressive increase of performance was recorded during 140 h operation with dry methane. The anode did not show any structure degradation after the electrochemical testing. Furthermore, no formation of carbon deposits was detected by electron microscopy and elemental analysis. Alternatively, this perovskite material showed significant chemical and structural modifications after high temperature treatment in a dry methane stream in a packed-bed reactor. It is derived that the continuous supply of mobile oxygen anions from the electrolyte to the LSFCO anode, promoted by the mixed conductivity of CGO electrolyte at 800 °C, stabilises the perovskite structure near the surface under SOFC operation and open circuit conditions.

  13. THE "CHEMICAL OXYGEN DEMAND / TOTAL VOLATILE ACIDS" RATIO AS AN ANAEROBIC TREATABILITY INDICATOR FOR LANDFILL LEACHATES

    OpenAIRE

    Contrera,R. C.; K. C. da Cruz Silva; G. H. Ribeiro Silva; D. M. Morita; Zaiat,M.; V. Schalch

    2015-01-01

    Abstract In some operational circumstances a fast evaluation of landfill leachate anaerobic treatability is necessary, and neither Biochemical Methane Potential nor BOD/COD ratio are fast enough. Looking for a fast indicator, this work evaluated the anaerobic treatability of landfill leachate from São Carlos-SP (Brazil) in a pilot scale Anaerobic Sequence Batch Biofilm Reactor (AnSBBR). The experiment was conducted at ambient temperature in the landfill area. After the acclimation, at a ...

  14. Methane on the greenhouse agenda

    Science.gov (United States)

    Hogan, Kathleen B.; Hoffman, John S.; Thompson, Anne M.

    1991-01-01

    Options for reducing methane emissions, which could have a significant effect on global warming, are addressed. Emissions from landfills, coal mining, oil and natural gas systems, ruminants, animal wastes and wastewater, rice cultivation, and biomass burning are considered. Methods for implementing these emission reductions are discussed.

  15. Coal Mine Methane in Russia

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    This paper discusses coal mine methane emissions (CMM) in the Russian Federation and the potential for their productive utilisation. It highlights specific opportunities for cost-effective reductions of CMM from oil and natural gas facilities, coal mines and landfills, with the aim of improving knowledge about effective policy approaches.

  16. Methane Dynamics in Flooded Lands

    Science.gov (United States)

    Methane (CH4) is the second most important anthropogenic greenhouse gas with a heat trapping capacity 34 times greater than that of carbon dioxide on a100 year time scale. Known anthropogenic CH4 sources include livestock production, rice agriculture, landfills, and natural gas m...

  17. Landfill gas as vehicle fuel; Deponigas som fordonsbraensle

    Energy Technology Data Exchange (ETDEWEB)

    Benjaminsson, Johan; Johansson, Nina; Karlsvaerd, Johan (Grontmij AB, Stockholm (Sweden))

    2010-03-15

    The landfill gas extraction in Sweden 2008 was 370 GWh. Mainly because of lack of available technologies for landfill gas upgrading and high assessed upgrading costs, landfill gas has so far only been used for heating and cogenerations plants (CHP). In recent years, interest has been brought to upgrade landfill gas and this study highlights the possibility of using landfill gas as fuel for vehicles. A decision in investment in an upgrading installation requires a forecast of future gas production and landfill gas extraction. From 2005, dispose of organic waste is prohibited, reducing the number of active landfills and the landfill gas production will go down. Factors such as moisture content, design of the final coverage and landfill gas collection system have a major impact on the extraction. It is therefore difficult to make appropriate predictions of the future gas production. Today's landfill gas extraction is approximately 35% of the landfill gas production and in the light of this, extraction can be in a level comparable to today's at least ten years ahead, provided that the extraction system is being expanded and that measurements are taken to so that landfills should not dry out. In comparison with biogas from anaerobic digestion in a dedicated digester, landfill gas has a high percentage of nitrogen and a content of many contaminants such as organic silicon compounds (siloxanes) and halogenated hydrocarbons (hydrocarbons containing the halogens chlorine, fluorine and bromine). This often requires more treatment and a further separation step. A common method for purification of landfill gas is regenerative adsorption on a dedicated adsorption material. Carbon dioxide is separated by conventional techniques like PSA, water scrubber and membranes. The main barrier to use landfill gas as vehicle fuel is a cost-effective separation of nitrogen that does not generate high methane losses. Nitrogen is separated by PSA or distillation technique (cryogenic

  18. The presence of hydrogenotrophic methanogens in the inoculum improves methane gas production in microbial electrolysis cells

    Directory of Open Access Journals (Sweden)

    Michael eSiegert

    2015-01-01

    Full Text Available High current densities in microbial electrolysis cells (MECs result from the predominance of various Geobacter species on the anode. MECs inoculated from different sources often converge in terms of current production and predominance of Geobacter species despite variability in the inoculum community. Relatively less is known about the effects of inoculum source on methane gas production in MECs, and specifically whether archaeal communities similarly converge to one specific genus. MECs were examined here on the basis of maximum methane production and current density relative to the inoculum community structure. We used anaerobic digester (AD sludge dominated by acetoclastic Methanosaeta species, and an anaerobic bog sediment where hydrogenotrophic methanogens were detected. Inoculation using solids to medium ratio of 25% w/v resulted in the highest methane production rates (0.27 mL mL–1 cm–2, gas volume normalized by liquid volume and cathode projected area and highest peak current densities (0.5 mA cm–2 for the bog sample. Methane production was independent of solid to medium ratio when AD sludge was used as the inoculum. 16S rRNA gene community analysis using pyrosequencing and qPCR confirmed the convergence of Archaea to Methanobacterium and Methanobrevibacter, and of Bacteria to Geobacter, despite their absence in AD sludge. Combined with other studies, these findings suggest that Archaea of the hydrogenotrophic genera Methanobacterium and Methanobrevibacter are the most important microorganisms for methane production in MECs and that their presence in the inoculum improves the performance.

  19. Landfilling: Concepts and Challenges

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Scharff, H.; Hjelmar, O.

    2011-01-01

    Landfilling of waste historically has been the main management route for waste, and in many parts of the world it still is. Landfills have developed from open polluting dumps to modern highly engineered facilities with sophisticated control measures and monitoring routines. However, in spite of all...... new approaches and technological advancement the landfill still is a long lasting accumulation of waste in the environment. Much of current landfill design and technology has been introduced as a reaction to problems encountered at actual landfills. The solution was in many cases sought in isolation...... to understand the concepts, the processes and the long-term aspects of landfilling. This chapter describes the main conceptual aspects of landfilling. The historical development is presented and key issues of time frames, mass balances and technical approaches are discussed. The environmental issues...

  20. Methane-free biogas for direct feeding of solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Leone, P.; Lanzini, A.; Santarelli, M.; Cali, M. [Dipartimento di Energetica, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin (Italy); Sagnelli, F.; Boulanger, A.; Scaletta, A.; Zitella, P. [BioEnergy Lab, Environment Park S.p.A., Via Livorno 60, 10144 Turin (Italy)

    2010-01-01

    This paper deals with the experimental analysis of the performance and degradation issues of a Ni-based anode-supported solid oxide fuel cell fed by a methane-free biogas from dark-anaerobic digestion of wastes by pastry and fruit shops. The biogas is produced by means of an innovative process where the biomass is fermented with a pre-treated bacteria inoculum (Clostridia) able to completely inhibit the methanization step during the fermentation process and to produce a H{sub 2}/CO{sub 2} mixture instead of conventional CH{sub 4}/CO{sub 2} anaerobic digested gas (bio-methane). The proposed biogas production route leads to a biogas composition which avoids the need of introducing a reformer agent into or before the SOFC anode in order to reformate it. In order to analyse the complete behaviour of a SOFC with the bio-hydrogen fuel, an experimental session with several H{sub 2}/CO{sub 2} synthetic mixtures was performed on an anode-supported solid oxide fuel cell with a Ni-based anode. It was found that side reactions occur with such mixtures in the typical thermodynamic conditions of SOFCs (650-800 C), which have an effect especially at high currents, due to the shift to a mixture consisting of hydrogen, carbon monoxide, carbon dioxide and water. However, cells operated with acceptable performance and carbon deposits (typical of a traditional hydrocarbon-containing biogas) were avoided after 50 h of cell operation even at 650 C. Experiments were also performed with traditional bio-methane from anaerobic digestion with 60/40 vol% of composition. It was found that the cell performance dropped after few hours of operation due to the formation of carbon deposits. A short-term test with the real as-produced biogas was also successfully performed. The cell showed an acceptable power output (at 800 C, 0.35 W cm{sup -2} with biogas, versus 0.55 W cm{sup -2} with H{sub 2}) although a huge quantity of sulphur was present in the feeding fuel (hydrogen sulphide at 103 ppm and

  1. Methane-free biogas for direct feeding of solid oxide fuel cells

    Science.gov (United States)

    Leone, P.; Lanzini, A.; Santarelli, M.; Calì, M.; Sagnelli, F.; Boulanger, A.; Scaletta, A.; Zitella, P.

    This paper deals with the experimental analysis of the performance and degradation issues of a Ni-based anode-supported solid oxide fuel cell fed by a methane-free biogas from dark-anaerobic digestion of wastes by pastry and fruit shops. The biogas is produced by means of an innovative process where the biomass is fermented with a pre-treated bacteria inoculum (Clostridia) able to completely inhibit the methanization step during the fermentation process and to produce a H 2/CO 2 mixture instead of conventional CH 4/CO 2 anaerobic digested gas (bio-methane). The proposed biogas production route leads to a biogas composition which avoids the need of introducing a reformer agent into or before the SOFC anode in order to reformate it. In order to analyse the complete behaviour of a SOFC with the bio-hydrogen fuel, an experimental session with several H 2/CO 2 synthetic mixtures was performed on an anode-supported solid oxide fuel cell with a Ni-based anode. It was found that side reactions occur with such mixtures in the typical thermodynamic conditions of SOFCs (650-800 °C), which have an effect especially at high currents, due to the shift to a mixture consisting of hydrogen, carbon monoxide, carbon dioxide and water. However, cells operated with acceptable performance and carbon deposits (typical of a traditional hydrocarbon-containing biogas) were avoided after 50 h of cell operation even at 650 °C. Experiments were also performed with traditional bio-methane from anaerobic digestion with 60/40 vol% of composition. It was found that the cell performance dropped after few hours of operation due to the formation of carbon deposits. A short-term test with the real as-produced biogas was also successfully performed. The cell showed an acceptable power output (at 800 °C, 0.35 W cm -2 with biogas, versus 0.55 W cm -2 with H 2) although a huge quantity of sulphur was present in the feeding fuel (hydrogen sulphide at 103 ppm and mercaptans up to 10 ppm). Therefore, it

  2. 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

  3. Ultrasound assisted biogas production from landfill leachate

    Energy Technology Data Exchange (ETDEWEB)

    Oz, Nilgün Ayman, E-mail: nilgunayman@comu.edu.tr; Yarimtepe, Canan Can

    2014-07-15

    Highlights: • Effect of low frequency ultrasound pretreatment on leachate was investigated. • Three different ultrasound energy inputs (200, 400 and 600 W/l) was applied. • Low-frequency ultrasound treatment increased soluble COD in landfill leachate. • Application of ultrasound to leachate increased biogas production about 40%. • Application of ultrasound to leachate increased total methane production rate about 20%. - Abstract: The aim of this study is to increase biogas production and methane yield from landfill leachate in anaerobic batch reactors by using low frequency ultrasound as a pretreatment step. In the first part of the study, optimum conditions for solubilization of organic matter in leachate samples were investigated using various sonication durations at an ultrasound frequency of 20 kHz. The level of organic matter solubilization during ultrasonic pretreatment experiments was determined by calculating the ratio of soluble chemical oxygen demand (sCOD) to total chemical oxygen demand (tCOD). The sCOD/tCOD ratio was increased from 47% in raw leachate to 63% after 45 min sonication at 600 W/l. Non-parametric Friedman’s test indicated that ultrasonic pretreatment has a significant effect on sCOD parameter for leachate (p < 0.05). In the second part of the study, anaerobic batch reactors were operated for both ultrasonically pretreated and untreated landfill leachate samples in order to assess the effect of sonication on biogas and methane production rate. In anaerobic batch reactor feed with ultrasonically pretreated leachate, 40% more biogas was obtained compared to the control reactor. For statistical analysis, Mann–Whitney U test was performed to compare biogas and methane production rates for raw and pretreated leachate samples and it has been found that ultrasonic pretreatment significantly enhanced biogas and methane production rates from leachate (p < 0.05) in anaerobic batch reactors. The overall results showed that low frequency

  4. High Efficiency Direct Methane Solid Oxide Fuel Cell System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA has a defined need for energy dense and highly efficient energy storage and power delivery systems for future space missions. Compared to other fuel cell...

  5. Kinetics of (reversible) internal reforming of methane in solid oxide fuel cells under stationary and APU conditions

    Science.gov (United States)

    Timmermann, H.; Sawady, W.; Reimert, R.; Ivers-Tiffée, E.

    The internal reforming of methane in a solid oxide fuel cell (SOFC) is investigated and modeled for flow conditions relevant to operation. To this end, measurements are performed on anode-supported cells (ASC), thereby varying gas composition (y CO = 4-15%, yH2 = 5 - 17 % , yCO2 = 6 - 18 % , yH2O = 2 - 30 % , yCH4 = 0.1 - 20 %) and temperature (600-850 °C). In this way, operating conditions for both stationary applications (methane-rich pre-reformate) as well as for auxiliary power unit (APU) applications (diesel-POX reformate) are represented. The reforming reaction is monitored in five different positions alongside the anodic gas channel by means of gas chromatography. It is shown that methane is converted in the flow field for methane-rich gas compositions, whereas under operation with diesel reformate the direction of the reaction is reversed for temperatures below 675 °C, i.e. (exothermic) methanation occurs along the anode. Using a reaction model, a rate equation for reforming could be derived which is also valid in the case of methanation. By introducing this equation into the reaction model the methane conversion along a catalytically active Ni-YSZ cermet SOFC anode can be simulated for the operating conditions specified above.

  6. [Research on fiber methane sensing system based on prism gas cell].

    Science.gov (United States)

    Wu, Xi-Jun; Wang, Yu-Tian; Liu, Xue-Cai; Li, Shu-Jun

    2010-05-01

    A novel fiber methane detection system was constructed based on integration of prism gas cell and harmonic detection technique. The system can be applied to broad-range concentration detection. Grounded on the Beer-Lambert approximation, the detection of various concentration (0-20%) of methane was completed using subtraction of background and ratio processing method, as the atmosphere surroundings was treated as background. The direct absorption spectra for various concentration were measured using GRIN gas cell, combined with available DFB-LD, and the R5 line of the 2v3 band of methane was selected as absorption peak. The system was tested online during gas mixing process and the linear relation between system indication and concentration variation was validated, while the stability and dynamic response characteristics was confirmed by experiments. The system sensitivity can be adjusted according to the concentration level of various field environments by changing the prism distance using step motor. So that, the system can be applied to various application fields and can be adopted as a monitoring instrument for coalmine tunnel and natural gas pipeline.

  7. Carbon and nitrogen removal and enhanced methane production in a microbial electrolysis cell.

    Science.gov (United States)

    Villano, Marianna; Scardala, Stefano; Aulenta, Federico; Majone, Mauro

    2013-02-01

    The anode of a two-chamber methane-producing microbial electrolysis cell (MEC) was poised at +0.200V vs. the standard hydrogen electrode (SHE) and continuously fed (1.08gCOD/Ld) with acetate in anaerobic mineral medium. A gas mixture (carbon dioxide 30vol.% in N(2)) was continuously added to the cathode for both pH control and carbonate supply. At the anode, 94% of the influent acetate was removed, mostly through anaerobic oxidation (91% coulombic efficiency); the resulting electric current was mainly recovered as methane (79% cathode capture efficiency). Low biomass growth was observed at the anode and ammonium was transferred through the cationic membrane and concentrated at the cathode. These findings suggest that the MEC can be used for the treatment of low-strength wastewater, with good energy efficiency and low sludge production.

  8. Optimization of dry reforming of methane over Ni/YSZ anodes for solid oxide fuel cells

    Science.gov (United States)

    Guerra, Cosimo; Lanzini, Andrea; Leone, Pierluigi; Santarelli, Massimo; Brandon, Nigel P.

    2014-01-01

    This work investigates the catalytic properties of Ni/YSZ anodes as electrodes of Solid Oxide Fuel Cells (SOFCs) to be operated under direct dry reforming of methane. The experimental test rig consists of a micro-reactor, where anode samples are characterized. The gas composition at the reactor outlet is monitored using a mass spectrometer. The kinetics of the reactions occurring over the anode is investigated by means of Isotherm reactions and Temperature-programmed reactions. The effect of the variation of temperature, gas residence time and inlet carbon dioxide-methane volumetric ratio is analyzed. At 800 °C, the best catalytic performance (in the carbon safe region) is obtained for 1.5 dry reforming and cracking reactions, respectively. In other ranges, dry reforming and reverse water gas shift are the dominant reactions and the inlet feed reaches almost the equilibrium condition provided that a sufficient gas residence time is obtained.

  9. Effect of earthworms on the community structure of active methanotrophic bacteria in a landfill cover soil.

    Science.gov (United States)

    Héry, Marina; Singer, Andrew C; Kumaresan, Deepak; Bodrossy, Levente; Stralis-Pavese, Nancy; Prosser, Jim I; Thompson, Ian P; Murrell, J Colin

    2008-01-01

    In the United Kingdom, landfills are the primary anthropogenic source of methane emissions. Methanotrophic bacteria present in landfill biocovers can significantly reduce methane emissions via their capacity to oxidize up to 100% of the methane produced. Several biotic and abiotic parameters regulate methane oxidation in soil, such as oxygen, moisture, methane concentration and temperature. Earthworm-mediated bioturbation has been linked to an increase in methanotrophy in a landfill biocover soil (AC Singer et al., unpublished), but the mechanism of this trophic interaction remains unclear. The aims of this study were to determine the composition of the active methanotroph community and to investigate the interactions between earthworms and bacteria in this landfill biocover soil where the methane oxidation activity was significantly increased by the earthworms. Soil microcosms were incubated with 13C-CH4 and with or without earthworms. DNA and RNA were extracted to characterize the soil bacterial communities, with a particular emphasis on methanotroph populations, using phylogenetic (16S ribosomal RNA) and functional methane monooxygenase (pmoA and mmoX) gene probes, coupled with denaturing gradient-gel electrophoresis, clone libraries and pmoA microarray analyses. Stable isotope probing (SIP) using 13C-CH4 substrate allowed us to link microbial function with identity of bacteria via selective recovery of 'heavy' 13C-labelled DNA or RNA and to assess the effect of earthworms on the active methanotroph populations. Both types I and II methanotrophs actively oxidized methane in the landfill soil studied. Results suggested that the earthworm-mediated increase in methane oxidation rate in the landfill soil was more likely to be due to the stimulation of bacterial growth or activity than to substantial shifts in the methanotroph community structure. A Bacteroidetes-related bacterium was identified only in the active bacterial community of earthworm-incubated soil but

  10. 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%A new way of natural mitigation of methane in a refuse landfill: Anaerobic and aerobic co-oxidation

    Institute of Scientific and Technical Information of China (English)

    韩丹; 石峰; 柴晓利; 陈浩泉; 赵由才

    2011-01-01

    The surface soil at 30 ~60 cm, refuse at 1.5 m depth and the aged refuse at the bottom of the refuse landfill were selected for experiments on sulfate-reducing bacteria (SRB). It was found that SRB existed in nearly all layers of the solid waste landfill, with aged refuse at the bottom containing the most and the surface soil the least SRB. Garbage samples with a 50%: 50% coarse:fine particle size proportion showed the best aerobic and anaerobic methane oxidation effect, and anaerobic oxidation accounted for above 20%. Microbial activity in aged refuse and co-oxidation rate of methane reached a maximum value with a 25% moisture content. Anaerobic oxidation rate could reach more than 30% as the moisture content approached 70%. Supplementation of exogenous methane could shorten the time of aerobic oxidation by 50%. However, both aerobic and anaerobic oxidation were weakened if the amount of exogenous methane was beyond 2 mL for the 20 g aged refuse. Therefore, a new way for natural mitigation of methane in a refuse landfill is put forward based on anaerobic and aerobic co-oxidation of methane.%采用暴雨过后垃圾填埋表层30~60 cm的覆土、表层1.5 m以下的垃圾,以及刚刚开挖出来的9年矿化垃圾进行硫酸盐还原菌阳性反应试验,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%;而初始甲烷一次通人量超过2 mL(20g矿化垃圾)后,甲烷好氧与厌氧氧化

  11. Saccharomyces cerevisiae Live Cells Decreased In vitro Methane Production in Intestinal Content of Pigs.

    Science.gov (United States)

    Gong, Y L; Liao, X D; Liang, J B; Jahromi, M F; Wang, H; Cao, Z; Wu, Y B

    2013-06-01

    An in vitro gas production technique was used in this study to elucidate the effect of two strains of active live yeast on methane (CH4) production in the large intestinal content of pigs to provide an insight to whether active live yeast could suppress CH4 production in the hindgut of pigs. Treatments used in this study include blank (no substrate and no live yeast cells), control (no live yeast cells) and yeast (YST) supplementation groups (supplemented with live yeast cells, YST1 or YST2). The yeast cultures contained 1.8×10(10) cells per g, which were added at the rates of 0.2 mg and 0.4 mg per ml of the fermented inoculum. Large intestinal contents were collected from 2 Duroc×Landrace×Yorkshire pigs, mixed with a phosphate buffer (1:2), and incubated anaerobically at 39°C for 24 h using 500 mg substrate (dry matter (DM) basis). Total gas and CH4 production decreased (pyeast. The methane production reduction potential (MRP) was calculated by assuming net methane concentration for the control as 100%. The MRP of yeast 2 was more than 25%. Compared with the control group, in vitro DM digestibility (IVDMD) and total volatile fatty acids (VFA) concentration increased (pyeast supplementation. Quantity of methanogenic archaea per milliliter of inoculum decreased (pyeast supplementation after 24 h of incubation. Our results suggest that live yeast cells suppressed in vitro CH4 production when inoculated into the large intestinal contents of pigs and shifted the fermentation pattern to favor propionate production together with an increased population of acetogenic bacteria, both of which serve as a competitive pathway for the available H2 resulting in the reduction of methanogenic archaea.

  12. Lateral gas transport in soil adjacent to an old landfill: factors governing gas migration

    DEFF Research Database (Denmark)

    Christophersen, Mette; Kjeldsen, Peter

    2001-01-01

    Field experiments investigating lateral gas transport in soil adjacent to an old landfill in Denmark during a one-year period were conducted. A significant seasonal variation, with low concentrations of methane and high concentrations of carbon dioxide in the summer, caused by methane oxidation...... migration of landfill gas was a very dynamic system and the concentrations of LFG at a specific place and depth changed dramatically within a very short time. The experiments showed that change in barometric pressure was an important factor affecting gas migration at the Skellingsted landfill in Denmark....

  13. Landfill Top Covers

    DEFF Research Database (Denmark)

    Scheutz, Charlotte; Kjeldsen, Peter

    2011-01-01

    is landscaped in order to fit into the surrounding area/environment or meet specific plans for the final use of the landfill. To fulfill the above listed requirements landfill covers are often multicomponent systems which are placed directly on top of the waste. The top cover may be placed immediately after...... the landfill section has been filled or several years later depending on the settlement patterns. Significant differential settlements may disturb the functioning of the top cover. The specific design of the cover system depends on the type of waste landfilled (municipal, hazardous, or inert waste...... however, top covers may be the only environmental protection measure. In some landfill regulations (for instance the Subtitle D landfills receiving municipal solid waste in the USA) it is required to minimize infiltration into the waste layers. Therefore top covers containing liner components...

  14. Diamond dissolution and the production of methane and other carbon-bearing species in hydrothermal diamond-anvil cells

    Science.gov (United States)

    Chou, I.-Ming; Anderson, Alan J.

    2009-01-01

    Raman analysis of the vapor phase formed after heating pure water to near critical (355-374 ??C) temperatures in a hydrothermal diamond-anvil cell (HDAC) reveals the synthesis of abiogenic methane. This unexpected result demonstrates the chemical reactivity of diamond at relatively low temperatures. The rate of methane production from the reaction between water and diamond increases with increasing temperature and is enhanced by the presence of a metal gasket (Re, Ir, or Inconel) which is compressed between the diamond anvils to seal the aqueous sample. The minimum detection limit for methane using Raman spectroscopy was determined to be ca. 0.047 MPa, indicating that more than 1.4 nanograms (or 8.6 ?? 10-11 mol) of methane were produced in the HDAC at 355 ??C and 30 MPa over a period of ten minutes. At temperatures of 650 ??C and greater, hydrogen and carbon dioxide were detected in addition to methane. The production of abiogenic methane, observed in all HDAC experiments where a gasket was used, necessitates a reexamination of the assumed chemical systems and intensive parameters reported in previous hydrothermal investigations employing diamonds. The results also demonstrate the need to minimize or eliminate the production of methane and other carbonic species in experiments by containing the sample within a HDAC without using a metal gasket.

  15. [Influence of substrate COD on methane production in single-chambered microbial electrolysis cell].

    Science.gov (United States)

    Teng, Wen-Kai; Liu, Guang-Li; Luo, Hai-Ping; Zhang, Ren-Duo; Fu, Shi-Yu

    2015-03-01

    The chemical oxygen demand (COD) of substrate can affect the microbial activity of both anode and cathode biofilm in the single-chamber methanogenic microbial electrolysis cell (MEC). In order to investigate the effect of COD on the performance of MEC, a single chamber MEC was constructed with biocathode. With the change of initial concentration of COD (700, 1 000 and 1 350 mg x L(-1)), the methane production rate, COD removal and energy efficiency in the MEC were examined under different applied voltages. The results showed that the methane production rate and COD removal increased with the increasing COD. With the applied voltage changing from 0.3 to 0.7 V, the methane production rate increased at the COD of 700 mg x L(-1), while it increased at first and then decreased at the COD of 1000 mg x L(-1) and 1350 mg x L(-1). A similar trend was observed for the COD removal. The cathode potential reached the minimum (- 0.694 ± 0.001) V as the applied voltage was 0.5 V, which therefore facilitated the growth of methanogenic bacteria and improved the methane production rate and energy efficiency of the MEC. The maximum energy income was 0.44 kJ ± 0.09 kJ (1450 kJ x m(-3)) in the MEC, which was obtained at the initial COD of 1000 mg x L(-1) and the applied voltage of 0.5 V. Methanogenic MECs could be used for the treatment of wastewaters containing low organic concentrations to achieve positive energy production, which might provide a new method to recover energy from low-strength domestic wastewater.

  16. Sanitary Landfill Leachate Recycle and Environmental Problems at Selected Army Landfills: Lessons Learned

    Science.gov (United States)

    1986-09-01

    Benson, M. J. Staub , and M. A. Kamlys, Characteristics, Control and Treatment of Leachate at Military Irnstallations, !nterim Report N- 97/ADA097035...D. Smith, R. Pileccia, J. Handy, G. Gerdes, S. Kloster, G. Schanche, _. .1. fJanson, M. J. Staub , and M. A. Kamiya, Characteri.tic.i Control, and...Learned N 1. Do not construct buildings on top of or close to a closed landfill until methane gas production has stopped.... - 2. Note that explosive

  17. Aerobic landfill bioreactor

    Science.gov (United States)

    Hudgins, Mark P; Bessette, Bernard J; March, John; McComb, Scott T.

    2000-01-01

    The present invention includes a method of decomposing municipal solid waste (MSW) within a landfill by converting the landfill to aerobic degradation in the following manner: (1) injecting air via the landfill leachate collection system (2) injecting air via vertical air injection wells installed within the waste mass; (3) applying leachate to the waste mass using a pressurized drip irrigation system; (4) allowing landfill gases to vent; and (5) adjusting air injection and recirculated leachate to achieve a 40% to 60% moisture level and a temperature between 120.degree. F. and 140.degree. F. in steady state.

  18. Optimizing gas extraction at landfills in Denmark; Optimering af gasindvinding pae deponeringsanlaeg i Danmark

    Energy Technology Data Exchange (ETDEWEB)

    Willumsen, H.C. [LFG Consult (Denmark)

    2005-07-01

    In landfills which contain organic material and anaerobic decomposition takes place, and landfill gas (LFG) is produced. The LFG contains approximately 50% methane, which contributes to the greenhouse effect when emitting from the landfill. Approximately 19% of the greenhouse gases in the atmosphere are methane, and around 8% of this is emission from landfills. This means that roughly 1.5% of the global warming is related to emission from landfills. Extraction of LFG for energy purposes was started 30 years ago in USA. In Denmark 26 LFG plants have been established since 1985. The gas is utilized for CHP or pure power production in gas engine/generator units. In some cases the LFG is used in gas burners in connection with boilers for district heating systems. 24 million m{sup 3} was recovered in 2004, which is equivalent to a reduction of CO{sub 2} of 160.000 tons CO{sub 2}/year. (BA)

  19. LIQUID NATURAL GAS (LNG): AN ALTERNATIVE FUEL FROM LANDFILL GAS (LFG) AND WASTEWATER DIGESTER GAS

    Energy Technology Data Exchange (ETDEWEB)

    VANDOR,D.

    1999-03-01

    This Research and Development Subcontract sought to find economic, technical and policy links between methane recovery at landfill and wastewater treatment sites in New York and Maryland, and ways to use that methane as an alternative fuel--compressed natural gas (CNG) or liquid natural gas (LNG) -- in centrally fueled Alternative Fueled Vehicles (AFVs).

  20. Separation of hydrogen from a hydrogen/methane mixture using PEM fuel cell technology

    Energy Technology Data Exchange (ETDEWEB)

    Ibeh, B.; Gardner, C.; Ternan, M. [Ottawa Univ., ON (Canada). Dept. of Chemical Engineering

    2007-07-01

    This paper presented a newly developed method for transporting hydrogen in natural gas pipelines which involves the use of an electrochemical separation process using proton exchange membrane (PEM) fuel cells. It described an experimental procedure in which a single cell 25 cm{sup 2} PEM fuel cell was used and anode polarization curves were determined. Hydrogen partial pressure was reduced as current density was increased to strengthen the anode potential. Hydrogen separation equations were presented in addition to a comparison of calculated and experimental polarization curves. Separation efficiencies were also described. Results of the experiment showed that hydrogen could be separated from the hydrogen-natural gas mixture through the use of PEM technology. It was also observed that methane behaved as an inert gas at low temperatures. Details of costs and capitalized costs for the separation process were also presented. Last, the presentation discussed issues related to electrode fouling by oxidation products and the efficiency of separation processes. tabs., figs.

  1. Cooling of a Diesel Reformate Fuelled Solid Oxide Fuel Cell by Internal Reforming of Methane: A Modelling Study

    Institute of Scientific and Technical Information of China (English)

    HUANG Xiaowei; Alexander Kromp

    2013-01-01

    In this paper a system combining a diesel reformer using catalytic partial oxidation (CPOX) with the Solid Oxide Fuel Cell (SOFC) for Auxiliary Power Unit (APU) applications is modeled with respect to the cooling effect provided by internal reforming of methane in anode gas channel.A model mixture consisting of 80% n-hexadecane and 20% 1-methylnaphthalin is used to simulate the commercial diesel.The modelling consists of several steps.First,equilibrium gas composition at the exit of CPOX reformer is modelled in terms oxygen to carbon (O/C) ratio,fuel utilization ratio and anode gas recirculation.Second,product composition,especially methane content,is determined for the methanation process at the operating temperatures ranging from 500 ℃ to 520 ℃.Finally,the cooling power provided by internal reforming of methane in SOFC fuel channel is calculated for two concepts to increase the methane content of the diesel reformate.The results show that the first concept,operating the diesel reformer at low O/C ratio and/or recirculation ratio,is not realizable due to high probability of coke formation,whereas the second concept,combining a methanation process with CPOX,can provide a significant cooling effect in addition to the conventional cooling concept which needs higher levels of excess air.

  2. Evaluation and application of site-specific data to revise the first-order decay model for estimating landfill gas generation and emissions at Danish landfills

    DEFF Research Database (Denmark)

    Mou, Zishen; Scheutz, Charlotte; Kjeldsen, Peter

    2015-01-01

    Methane (CH4) generated from low-organic waste degradation at four Danish landfills was estimated by three first-order decay (FOD) landfill gas (LFG) generation models (LandGEM, IPCC, and Afvalzorg). Actual waste data from Danish landfills were applied to fit model (IPCC and Afvalzorg) required...... categories. In general, the single-phase model, LandGEM, significantly overestimated CH4 generation, because it applied too high default values for key parameters to handle low-organic waste scenarios. The key parameters were biochemical CH4 potential (BMP) and CH4 generation rate constant (k.......Implications: Landfill operators use the first-order decay (FOD) models to estimate methane (CH4) generation. A single-phase model (LandGEM) and a traditional model (IPCC) could result in overestimation when handling a low-organic waste scenario. Site-specific data were important and capable of calibrating key parameter...

  3. 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

  4. Methanotrophy in London, UK, Landfill Topsoil: Microbiology, Stable Carbon Isotopes, Seasonal Variation and Laboratory Model Study

    Science.gov (United States)

    Sriskantharajah, S.; Fisher, R.; Lowry, D.; Grassineau, N.; Nisbet, E. G.

    2004-12-01

    Landfill is a major source of methane emissions into the atmosphere. Aerobic soil is also a good sink of methane, as it is inhabited by methane consuming bacteria, methanotrophs. Methanotrophic bacteria were cultured from landfill soil samples. Three genera of methanotrophs were cultured: Methylocaldum, Methylosinus and Methylomonas. Interestingly, the only established members of the Methylocaldum genus are all thermophilic, whilst those isolated in this study are mesophilic. This suggests that those Methylocaldum methanotrophs found in landfills may have migrated from hot spring natural settings. Representatives of each genera were inoculated into a simple topsoil model and subjected to variations in temperature, methane concentration and incubation periods. As expected, temperature greatly affected methane oxidation, but methane concentration affected the rate of oxidation far more than expected. The model study implies that the complete combustion of methane to carbon dioxide is greatly affected by temperature and methane availability, whilst the effect on the uptake of methane is not as great. Seasonal variations in methane concentrations within the topsoil were monitored over a one year period from November 2002 to October 2003 and show that methane flow through the topsoil, and consequently methanotrophy, is strongly controlled by meteorology, mainly air temperature and pressure. Generally, methanotrophy was low during colder months and higher at during warmer months, but changes in air pressure complicate this by controlling the rate of flow of methane through the topsoil. δ 13C analyses of methane and carbon dioxide emitted from landfill topsoil showed that there was a great deal of methanotrophic activity during the warmer months of 2003, with most fractionation of residual methane occurring during August. During the heat wave experienced in the UK in August 2003, the δ 13C from borehole samples of methane in the anaerobic zone shifted from -57‰ to -16

  5. Strategies to Optimize Microbially-Mediated Mitigation of Greenhouse Gas Emissions from Landfill Cover Soils

    Energy Technology Data Exchange (ETDEWEB)

    Jeremy Semrau; Sung-Woo Lee; Jeongdae Im; Sukhwan Yoon; Michael Barcelona

    2010-09-30

    The overall objective of this project, 'Strategies to Optimize Microbially-Mediated Mitigation of Greenhouse Gas Emissions from Landfill Cover Soils' was to develop effective, efficient, and economic methodologies by which microbial production of nitrous oxide can be minimized while also maximizing microbial consumption of methane in landfill cover soils. A combination of laboratory and field site experiments found that the addition of nitrogen and phenylacetylene stimulated in situ methane oxidation while minimizing nitrous oxide production. Molecular analyses also indicated that methane-oxidizing bacteria may play a significant role in not only removing methane, but in nitrous oxide production as well, although the contribution of ammonia-oxidizing archaea to nitrous oxide production can not be excluded at this time. Future efforts to control both methane and nitrous oxide emissions from landfills as well as from other environments (e.g., agricultural soils) should consider these issues. Finally, a methanotrophic biofiltration system was designed and modeled for the promotion of methanotrophic activity in local methane 'hotspots' such as landfills. Model results as well as economic analyses of these biofilters indicate that the use of methanotrophic biofilters for controlling methane emissions is technically feasible, and provided either the costs of biofilter construction and operation are reduced or the value of CO{sub 2} credits is increased, can also be economically attractive.

  6. Modeling and optimization of catalytic partial oxidation methane reforming for fuel cells

    Science.gov (United States)

    Chaniotis, A. K.; Poulikakos, D.

    The objective of this paper is the investigation and optimization of a micro-reformer for a fuel cell unit based on catalytic partial oxidation using a systematic numerical study of chemical composition and inflow conditions. The optimization targets hydrogen production from methane. Additionally, the operating temperature, the amount of carbon formation and the methane conversion efficiency are taking into account. The fundamental investigation is first based on simplified reactor models (surface perfectly stirred reactor (SPRS)). A detailed surface chemistry mechanism is adopted in order to capture all the important features of the reforming process. As a consequence, the residence time of the process is taken into account, which means that the products are not necessary in equilibrium. Subsequently, in order to test the validity of the findings from the simplified reactor model, more detailed simulations (involving the Navier-Stokes equations) were performed for the regions of interest. A region where all the targeted operating conditions are satisfied and the yield of hydrogen is around 80% is identified.

  7. Temperature effect on electrochemical promotion of syngas cogeneration in direct-methane solid oxide fuel cells

    Science.gov (United States)

    Huang, Ta-Jen; Huang, Meng-Chin

    Syngas cogeneration in direct-methane solid oxide fuel cells with Ni-yttria-stabilized zirconia (YSZ) anodes was studied with temperature varying from 700 to 900 °C. A phenomenon of electrochemical promotion of bulk lattice-oxygen extraction from the YSZ electrolyte was observed. With increasing temperature, this promotion effect increases while both the rate enhancement ratios of CO and CO 2 formations decrease. The activation energy of CO and CO 2 formation under close circuit is lower than that under open circuit. The activation energy for the lattice-oxygen extraction from the YSZ bulk is higher than that for the oxygen transport through the YSZ bulk. The process of lattice-oxygen extraction from YSZ is rate determining in direct-methane oxidation under the condition of either close circuit or open circuit. The dependence of CO formation rate on the oxygen supply rate is stronger than that of CO 2 formation rate. Electrochemical promotion of bulk lattice-oxygen extraction enhances syngas cogeneration.

  8. Groundwater geochemistry of a municipal landfill in Araras, SP

    Directory of Open Access Journals (Sweden)

    Carlos Frederico de Castro Alves 1

    2014-03-01

    Full Text Available A contaminated area associated with a residential unlined landfill, located in Araras, was investigated. The aim of this work was to develop a hydrogeological and geochemical conceptual model in order to identify the redox zones related to the landfill and to explain the main processes resulting from the impact of leachates on the local groundwaters and soil. The work consisted of a surface geological mapping, geophysical survey with electric tomography, logging of subsoil boreholes, an installation of monitoring wells and soil, gas, leachate and groundwater samples analyses. The results show that the Araras landfill is in the methanogenic phase and promotes alterations in local groundwater quality. The main parameters of environmental interest identified in the leachate were total dissolved solids, biochemical oxygen demand, ammonium, methane, Na, Cl, Fe, Mn, Ba, B, Co and Cd. According to criteria specifically developed for this landfill, the following redox zones were identified in the groundwater: (i aerobic, located upgradient from the landfill; (ii methanogenic, downgradient from the landfill; (iii iron and/or manganese reduction, located between the methanogenic zone and the Araras river. Bypassing the iron and/or manganese redox zone, the existence of a denitrification zone was inferred. Besides the redox reactions in these zones, other processes that mitigate the impact of leachate into groundwater were also discovered: dilution, degradation by the action of surface microorganisms, dispersion, ionic exchange, formation of organic and inorganic complexes, dissolution and precipitation.

  9. A review on utilization of combustible waste gas (II):Landfill gas,flare gas,associated gas and coalbed methane%可燃废气利用技术研究进展(Ⅱ):填埋气、火炬气、伴生天然气和煤矿瓦斯

    Institute of Scientific and Technical Information of China (English)

    王一坤; 陈国辉; 雷小苗; 王长安; 邓磊; 车得福

    2014-01-01

    The utilization of combustible waste gas is an important way of energy conservation and emission reduction.The progress in utilization technologies of landfill gas,flare gas,associated gas and coalbed methane has been presented.Due to the very low utilization ratio and insufficient resourceful utilization of landfill gas,the waste landfill treatment of which the leachate treatment and efficient LFG extraction and utilization are the key technologies should be widely popularized.Generally,the flare gas is fired to provide heat which is then recycled by waste heat boiler.Sometimes it can be directly burned in gas turbine for power generation.With low yield,the associated gas can be used as the inj ection fluid for oil production,or for field power generation.When the yield is high and stable,the associated gas can be transported by pipe-lines,liquid natural gas (LNG)and compressed natural gas (CNG)ships.The optimal utilization of low concentration coalbed methane is for gas-steam combined cycle power generation,of which the power gen-eration efficiency can reach up to higher than 45%.Usually,the coalbed methane is applied as assistant air in mine-mouth power plants,for the technical requirements and cost of this method are the lowest.%可燃废气利用是实现我国节能减排的重要途径之一。介绍了目前填埋气、火炬气、伴生天然气和煤矿瓦斯几种可燃废气的利用技术和工业应用现状。其中:填埋气的利用率很低,资源化利用技术不足,需大力推广以渗滤液处理、高效LFG抽排及利用为核心的填埋垃圾处理工艺;火炬气通常引入燃油或燃气锅炉加以利用,也可以将火炬气燃烧后利用余热锅炉回收热量,或者作为中等热值的气体,直接引入燃气轮机燃烧发电;伴生天然气的产量不高时,可以将其回注驱油或就地发电,产量高且稳定时,可以采用管道输送、液化天然气(LNG)和压缩天然气(CNG

  10. Co-generation potentials of municipal solid waste landfills in Serbia

    Directory of Open Access Journals (Sweden)

    Bošković Goran B.

    2016-01-01

    Full Text Available Waste management in the Republic of Serbia is based on landfilling. As a result of such year-long practice, a huge number of municipal waste landfills has been created where landfill gas has been generated. Landfill gas, which is essentially methane (50-55% and carbon dioxide (40-45% (both GHGs, has a great environmental impact which can be reduced by using landfill gas in cogeneration plants to produce energy. The aim of this paper is to determine economic and environmental benefits from such energy production. For that purpose, the database of cogeneration potentials (CP of 51 landfills in the Republic of Serbia (RS was created. Amount of landfill gas generated at each municipal landfill was calculated by applying a first order decay equation which requires the data about solid waste production and composition and about some landfill characteristics. For all landfills, which have over 100,000 m3 each, a techno-economic analysis about building a CHP plant was conducted. The results have shown, that the total investment in 14 CHP plants with payback period of less than 7 years amounts € 11,721,288. The total nominal power of these plants is 7 MW of electrical power and 7.9 MW of thermal power, and an average payback period is about 61 months. In addition, using landfill biogas as energy source in proposed plants would reduce methane emission for 161,000 tons of CO2 equivalent per year. [Projekat Ministarstva nauke Republike Srbije, br. III 42013: Research of cogeneration potential of municipal and industrial energy power plant in Republic of Serbia and opportunities for rehabilitation of existing and construction of new cogeneration plants

  11. Landfilling of waste: accounting of greenhouse gases and global warming contributions.

    Science.gov (United States)

    Manfredi, Simone; Tonini, Davide; Christensen, Thomas H; Scharff, Heijo

    2009-11-01

    Accounting of greenhouse gas (GHG) emissions from waste landfilling is summarized with the focus on processes and technical data for a number of different landfilling technologies: open dump (which was included as the worst-case-scenario), conventional landfills with flares and with energy recovery, and landfills receiving low-organic-carbon waste. The results showed that direct emissions of GHG from the landfill systems (primarily dispersive release of methane) are the major contributions to the GHG accounting, up to about 1000 kg CO(2)-eq. tonne( -1) for the open dump, 300 kg CO(2)-eq. tonne( -1) for conventional landfilling of mixed waste and 70 kg CO(2)-eq. tonne(-1) for low-organic-carbon waste landfills. The load caused by indirect, upstream emissions from provision of energy and materials to the landfill was low, here estimated to be up to 16 kg CO(2)-eq. tonne(-1). On the other hand, utilization of landfill gas for electricity generation contributed to major savings, in most cases, corresponding to about half of the load caused by direct GHG emission from the landfill. However, this saving can vary significantly depending on what the generated electricity substitutes for. Significant amounts of biogenic carbon may still be stored within the landfill body after 100 years, which here is counted as a saved GHG emission. With respect to landfilling of mixed waste with energy recovery, the net, average GHG accounting ranged from about -70 to 30 kg CO(2)-eq. tonne(- 1), obtained by summing the direct and indirect (upstream and downstream) emissions and accounting for stored biogenic carbon as a saving. However, if binding of biogenic carbon was not accounted for, the overall GHG load would be in the range of 60 to 300 kg CO(2)-eq. tonne( -1). This paper clearly shows that electricity generation as well as accounting of stored biogenic carbon are crucial to the accounting of GHG of waste landfilling.

  12. Coal Mine Methane in Russia [Russian Version

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    This paper discusses coal mine methane emissions (CMM) in the Russian Federation and the potential for their productive utilisation. It highlights specific opportunities for cost-effective reductions of CMM from oil and natural gas facilities, coal mines and landfills, with the aim of improving knowledge about effective policy approaches.

  13. [Application of cowl in semi-aerobic landfill and its influence in initial stage].

    Science.gov (United States)

    Han, Dan; Zhao, You-cai; Xue, Bin-jie; Gao, Pin

    2009-10-15

    Enhancement of semi-aerobic landfill performance through a cowl installed on the gas ventilation pipeline using a simulated landfill box with 2 m x 1 m x 2 m in size was investigated, aiming at the maximum methane emission reduction. Influence of cowl on semi-aerobic environment formation was explored, and variety of methane and carbon dioxide concentrations at different wind speeds and mechanism of cowl operation were identified to provide information on design and improvement of semi-aerobic landfill. The results show that the cowl speeds up the semi-aerobic environment to shape, from over 50 days down to approximately 40 days, and reduces methane emission by promoting methane transformation to carbon dioxide. When the cowl is taken off suddenly during the normal operation, carbon dioxide concentration falls to 15.88% from the initial 16.67% immediately, and methane concentration increases to 16.12% from 6.14%. However, the carbon dioxide and methane concentration becomes 19.18% and 10.05%, respectively, as the cowl is taken on again. Additionally, methane emissions in the exhaust gas were monitored at different wind speeds of 2.0, 3.5, 5.0, 6.5, 8.0 m/s, and finds that the methane concentration reduces from the initial 15% to below 5% when the wind speed increases from 2 m/s to 8 m/s.

  14. Behavior of engineered nanoparticles in landfill leachate.

    Science.gov (United States)

    Bolyard, Stephanie C; Reinhart, Debra R; Santra, Swadeshmukul

    2013-08-01

    This research sought to understand the behavior of engineered nanoparticles in landfill leachate by examining the interactions between nanoparticles and leachate components. The primary foci of this paper are the effects of ZnO, TiO2, and Ag nanoparticles on biological landfill processes and the form of Zn, Ti, and Ag in leachate following the addition of nanoparticles. Insight into the behavior of nanoparticles in landfill leachate was gained from the observed increase in the aqueous concentrations over background for Zn, Ti, and Ag in some tested leachates attributed to leachate components interacting with the nanoparticle coatings resulting in dispersion, dissolution/dissociation, and/or agglomeration. Coated nanoparticles did not affect biological processes when added to leachate; five-day biochemical oxygen demand and biochemical methane potential results were not statistically different when exposed to nanoparticles, presumably due to the low concentration of dissolved free ionic forms of the associated metals resulting from the interaction with leachate components. Chemical speciation modeling predicted that dissolved Zn in leachate was primarily associated with dissolved organic matter, Ti with hydroxide, and Ag with hydrogen sulfide and ammonia; less than 1% of dissolved Zn and Ag was in the free ionic form, and free ionic Ti and Ag concentrations were negligible.

  15. Ultrasound assisted biogas production from landfill leachate.

    Science.gov (United States)

    Oz, Nilgün Ayman; Yarimtepe, Canan Can

    2014-07-01

    The aim of this study is to increase biogas production and methane yield from landfill leachate in anaerobic batch reactors by using low frequency ultrasound as a pretreatment step. In the first part of the study, optimum conditions for solubilization of organic matter in leachate samples were investigated using various sonication durations at an ultrasound frequency of 20 kHz. The level of organic matter solubilization during ultrasonic pretreatment experiments was determined by calculating the ratio of soluble chemical oxygen demand (sCOD) to total chemical oxygen demand (tCOD). The sCOD/tCOD ratio was increased from 47% in raw leachate to 63% after 45 min sonication at 600 W/l. Non-parametric Friedman's test indicated that ultrasonic pretreatment has a significant effect on sCOD parameter for leachate (pbiogas and methane production rate. In anaerobic batch reactor feed with ultrasonically pretreated leachate, 40% more biogas was obtained compared to the control reactor. For statistical analysis, Mann-Whitney U test was performed to compare biogas and methane production rates for raw and pretreated leachate samples and it has been found that ultrasonic pretreatment significantly enhanced biogas and methane production rates from leachate (p<0.05) in anaerobic batch reactors. The overall results showed that low frequency ultrasound pretreatment can be potentially used for wastewater management especially with integration of anaerobic processes.

  16. Hydrogen and methane production from swine wastewater using microbial electrolysis cells.

    Science.gov (United States)

    Wagner, Rachel C; Regan, John M; Oh, Sang-Eun; Zuo, Yi; Logan, Bruce E

    2009-03-01

    The production of a useful and valuable product during swine wastewater treatment, such as hydrogen gas, could help to lower treatment costs. Hydrogen can theoretically be produced from wastewater by electrohydrogenesis in a microbial electrolysis cell (MEC) or by fermentation. Using a single-chamber MEC with a graphite-fiber brush anode, hydrogen gas was generated at 0.9-1.0 m(3) m(-3) day(-1) H2 using a full-strength or diluted swine wastewater. COD removals ranged from 8 to 29% in 20-h tests, and from 69 to 75% in longer tests (184 h) using full-strength wastewater. The gas produced was up to 77+/-11% hydrogen, with overall recoveries of up to 28+/-6% of the COD in the wastewater as hydrogen gas. Methane was also produced at a maximum of 13+/-4% of total gas volume. The efficiency of hydrogen production, based on the electrical energy needed (but excluding the energy in the wastewater) compared to the energy of the hydrogen gas produced, was as high as 190+/-39% in 42-h batch tests with undiluted wastewater, but was lower in longer batch tests of 184 h (91+/-6%). Hydrogen gas could not be recovered in fermentation tests using wastewater with a heat-treated inoculum. Hydrogen production was shown to be possible by fermentation when the wastewater was sterilized, but this process would not be practical or energy efficient. We therefore conclude from these tests that MECs are an effective method for hydrogen recovery from swine wastewater treatment, although the process needs to be further evaluated for reducing methane production, increasing the efficiency of converting the organic matter into current, and increasing recovery of hydrogen gas produced at the cathode.

  17. Bacterial community composition and abundance in leachate of semi-aerobic and anaerobic landfills

    Institute of Scientific and Technical Information of China (English)

    Wei Zhang; Bo Yue; Qi Wang; Zechun Huang; Qifei Huang; Zengqiang Zhang

    2011-01-01

    The abundance and phylogenetic composition of bacterial community in leachate of semi-aerobic and anaerobic landfill were compared through real-time polymerase chain reaction and denaturing gradient gel electrophoresis.In semi-aerobic landfill scenario,the bacterial 16S rRNA copy numbers in leachate had no significant reduction from initial stage to stable period.In the scenario of anaerobic landfill,the largest bacterial 16S rRNA gene copy number was found in leachate at initial stage,but it reduced significantly at stable period.Moreover,methane-oxidizing bacteria population in stable period was lower than that in initial period in both two landfill processes.However,semi-aerobic landfill leachate had more methanotrophic bacteria populations than that in the anaerobic one.Furthermore,according to the sequences and phylogenetic analysis,obvious difference could be detected in bacterial community composition in different scenarios.Proteobacteria and bacteroidetes took up a dominantly higher proportion in semi-aerobic landfill leachate.To summarize up,different landfill methods and its landfill ages had crucial impacts on bacterial abundance and composition in leachate of semi-aerobic and anaerobic landfills.

  18. N 2O emissions at municipal solid waste landfill sites: Effects of CH 4 emissions and cover soil

    Science.gov (United States)

    Zhang, Houhu; He, Pinjing; Shao, Liming

    Municipal solid waste landfills are the significant anthropogenic sources of N 2O due to the cooxidation of ammonia by methane-oxidizing bacteria in cover soils. Such bacteria could be developed through CH 4 fumigation, as evidenced by both laboratory incubation and field measurement. During a 10-day incubation with leachate addition, the average N 2O fluxes in the soil samples, collected from the three selected landfill covers, were multiplied by 1.75 ( p landfill sites, N 2O fluxes in two landfill sites were significantly correlated with the variations of the CH 4 emissions without landfill gas recovery ( p landfill gas recovery in another landfill site ( p > 0.05). The annual average N 2O flux was 176 ± 566 μg N 2O-N m -2 h -1 ( p landfill site, which was 72% ( p landfill sites, respectively. The magnitude order of N 2O emissions in three landfill sites was also coincident by the results of laboratory incubation, suggesting the sandy soil cover could mitigate landfill N 2O emissions.

  19. Turkey Run Landfill Emissions Dataset

    Data.gov (United States)

    U.S. Environmental Protection Agency — landfill emissions measurements for the Turkey run landfill in Georgia. This dataset is associated with the following publication: De la Cruz, F., R. Green, G....

  20. Compositional and physicochemical changes in waste materials and biogas production across 7 landfill sites in UK.

    Science.gov (United States)

    Frank, R R; Cipullo, S; Garcia, J; Davies, S; Wagland, S T; Villa, R; Trois, C; Coulon, F

    2016-08-28

    The aim of this study was to evaluate the spatial distribution of the paper and fines across seven landfill sites (LFS) and assess the relationship between waste physicochemical properties and biogas production. Physicochemical analysis of the waste samples demonstrated that there were no clear trends in the spatial distribution of total solids (TS), moisture content (MC) and waste organic strength (VS) across all LFS. There was however noticeable difference between samples from the same landfill site. The effect of landfill age on waste physicochemical properties showed no clear relationship, thus, providing evidence that waste remains dormant and non-degraded for long periods of time. Landfill age was however directly correlated with the biochemical methane potential (BMP) of waste; with the highest BMP obtained from the most recent LFS. BMP was also correlated with depth as the average methane production decreased linearly with increasing depth. There was also a high degree of correlation between the Enzymatic Hydrolysis Test (EHT) and BMP test results, which motivates its potential use as an alternative to the BMP test method. Further to this, there were also positive correlations between MC and VS, VS and biogas volume and biogas volume and CH4 content. Outcomes of this work can be used to inform waste degradation and methane enhancement strategies for improving recovery of methane from landfills.

  1. Evaluating Gas Emissions From Landfills – Which Methodologies Can Be Used?

    DEFF Research Database (Denmark)

    Kjeldsen, Peter; Scheutz, Charlotte

    2011-01-01

    Many methodologies exist to measure whole landfill methane emission as alternatives to imprecise estimation of the methane emission using existing landfill gas generation models. An overview of the different measurement methodologies is given, and suggestions to the most promising methodologies...... are presented. Methods based on the tracer dilution approach are most promising. However, still some developments are needed, both in respect to the technical implementation, and in respect to the protocols needed to obtain annual emission estimates based on the limited number of measurement campaigns....

  2. Distribution of Redox-Sensitive Groundwater Quality Parameters Downgradient of a Landfill (Grindsted, Denmark)

    DEFF Research Database (Denmark)

    Bjerg, Poul Løgstrup; Rügge, Kirsten; Pedersen, Jørn K.;

    1995-01-01

    , dinitrogen oxide, nitrite, nitrate, and oxygen in the groundwater samples indicate that methane production, sulfate reduction, iron reduction, manganese reduction, and nitrate reduction take place in the plume. Adjacent to the landfill, methanogenic and sulfatereducing zones were identified, while aerobic......The leachate plume stretching 300 m downgradient from the Grindsted Landfill (Denmark) has been characterized in terms of redox-sensitive groundwater quality parameters along two longitudinal transects (285 samples). Variations in the levels of methane, sulfide, iron(ll), manganese(ll), ammonium...

  3. Effect of leachate recycle and inoculation on microbial characteristics of municipal refuse in landfill bioreactors

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Population development of key groups of anaerobic and aerobic bacteria involved in municipal refuse decomposition under laboratory landfill bioreactors with and without leachate recycle adinoculation was measured since modeling municipal refuse was landfilled in bioreactors for about 210 days. Hydrolytic fermentative bacteria (HFB), hydrogen-producing acetogenic bacteria (HPAB), methane-producing bacteria (MPB), sulfate-reducing bacteria (SRB), anaerobic and aerobic cellulolytic bacteria and denitrabacteria were enumerated by the most probable number technique. The results showed that the dominant microorganismgroups were the methanogenic bacteria including hydrolytic fermentative, hydrogen-producing acetogenic and methane-producing bacteria. They were present in fresh refuse but at low values and positively affected by leachate recycle and refuse inoculation. The amounts of HFB or HPAB in digesters D4 and D5 operated with noculation and leachate recycle reached their maximum values of1010-1012 cells/g dry refuse for HFB or 105-106 cells/g dry refuse for HPAB on day 60, in digester D3 operated with leachate recycle on day 120 for HFB (109 cells/g dry refuse) or on day 90 for HPAB (105 cells/g dry refuse), and in digesters D1 and D2 on day 210 for HFB (109 cells/g dry refuse) or on day 90 for HPAB (104-106 cells/g dry refuse). The population of methane-producing bacteria in digesters D4 and D5 sharply increased on days 60 and 90 respectively, however in igesters D1, D2 and D3 on day 120. Leachate recycle and inoculation changed the cellulolytic microorganisms composition of refuse ecosystem, the higher amounts of anaerobic cellulolytic bacteria were measured in digesters D4 and D5 (107 cells/g dry refuse), followed by digesters D3 (106 cells/g dry refuse), D2 or D1(104 cells/g dry refuse). However, the amounts of aerobic cellulolytic bacteria were much lower than that of anaerobic cellulolytic bacteria. And it was higher in digester D3 than those in digesters D1, D2

  4. Characterization of methane production and microbial community shifts during waste activated sludge degradation in microbial electrolysis cells.

    Science.gov (United States)

    Sun, Rui; Zhou, Aijuan; Jia, Jianna; Liang, Qing; Liu, Qian; Xing, Defeng; Ren, Nanqi

    2015-01-01

    Microbial electrolysis cell (MECs) were investigated as a promising technology to manage waste activated sludge (WAS) reduction and bio-methane generation. The effect of WAS concentration on the MECs performance was discussed. At the optimal concentration of 15gCOD/L, maximum methane yield of MECs fed with alkaline pretreated WAS (A-WAS) were achieved with the value of 77.13±2.52LCH4/kg-COD on Day 3, which had been improved by 1.5-fold compared with MECs fed with raw WAS (R-WAS), while that was negligible in open circuit controls. Efficient sludge reduction was also obtained in terms of TCOD, total protein, TSS and VSS removal. Pyrosequencing revealed the dominance of exoelectrogen Geobacter and hydrogen-producing bacteria Petrimonas in MECs fed with WAS. Methanocorpusculum with the capacity of methane generation using CO2 and H2 also showed overwhelming dominance (96.01%). The large proportions of Petrimonas and Methanocorpusculum indicated the occurrence of hydrogenotrophic methanogenesis in our methane-producing MECs.

  5. Analysis of the economic potential of the landfill in the municipality of Chapeco - SC, Brazil; Analise do potencial economico do aterro sanitario do municipio de Chapeco - SC

    Energy Technology Data Exchange (ETDEWEB)

    Cansian, Maricy Moreno, Email: maricymc@gmail.com

    2006-07-01

    This study aims to evaluate the economic and environmental viability of the exploitation of methane gas (CH4) - biogas - concentrated at the bottom of the mountains of waste from landfill Chapeco for power generation. The landfill receives approximately of 80 tons / day, the vast majority of domestic origin.

  6. Sustainable Approach for Landfill Management at Final Processing Site Cikundul in Sukabumi City, Indonesia

    Directory of Open Access Journals (Sweden)

    Sri Darwati

    2012-01-01

    Full Text Available The main problem of landfill management in Indonesia is the difficulty in getting a location for Final Processing Sites (FPS due to limited land and high land prices. Besides, about 95% of existing landfills are uncontrolled dumping sites, which could potentially lead to water, soil and air pollution. Based on data from the Ministry of Environment (2010, The Act of the Republic of Indonesia Number 18 Year 2008 Concerning Solid Waste Management, prohibits open dumping at final processing sites and in ratification, the Local Governments have to convert the open dump sites into controlled or sanitary landfill. The Research Institute for Human Settlements has been conducting multi-year researches related to the rehabilitation of dumpsites toward sustainable landfill. The research methods are literature reviews, experiments, laboratory analysis and field observations. A pilot model of dumpsite rehabilitation was carried out in 2010 at the Final Processing Site at Cikundul in Sukabumi City, consisting of (1 mining landfill (2 construction of landfill cells in a former mining area with a semi aerobic landfill and an anaerobic landfill and (3 landfill operations using decomposed material from landfill mining as a soil cover. The purpose of the study is to develop a sustainable approach for landfill management and rehabilitation through landfill mining and implementation of semi aerobic landfill. Findings in the construction of landfill mining indicate that (1 the construction of landfill mining is constrained by leachate that is trapped in a pile of waste, therefore, the leachate needs to be pumped to leachate treatment installations, (2 the volume of waste excavation is expanding due to the high plastic content of about 26% in landfills (3 the potency of decomposed materials from landfill mining is 40–83% for landfill operations or greening.. The performance of landfill systems shows that leachate quality of semi aerobic landfill tends to be lower

  7. Direct methane solid oxide fuel cells based on catalytic partial oxidation enabling complete coking tolerance of Ni-based anodes

    Science.gov (United States)

    Lee, Daehee; Myung, Jaeha; Tan, Jeiwan; Hyun, Sang-Hoon; Irvine, John T. S.; Kim, Joosun; Moon, Jooho

    2017-03-01

    Solid oxide fuel cells (SOFCs) can oxidize diverse fuels by harnessing oxygen ions. Benefited by this feature, direct utilization of hydrocarbon fuels without external reformers allows for cost-effective realization of SOFC systems. Superior hydrocarbon reforming catalysts such as nickel are required for this application. However, carbon coking on nickel-based anodes and the low efficiency associated with hydrocarbon fueling relegate these systems to immature technologies. Herein, we present methane-fueled SOFCs operated under conditions of catalytic partial oxidation (CPOX). Utilizing CPOX eliminates carbon coking on Ni and facilitates the oxidation of methane. Ni-gadolinium-doped ceria (GDC) anode-based cells exhibit exceptional power densities of 1.35 W cm-2 at 650 °C and 0.74 W cm-2 at 550 °C, with stable operation over 500 h, while the similarly prepared Ni-yttria stabilized zirconia anode-based cells exhibit a power density of 0.27 W cm-2 at 650 °C, showing gradual degradation. Chemical analyses suggest that combining GDC with the Ni anode prevents the oxidation of Ni due to the oxygen exchange ability of GDC. In addition, CPOX operation allows the usage of stainless steel current collectors. Our results demonstrate that high-performance SOFCs utilizing methane CPOX can be realized without deterioration of Ni-based anodes using cost-effective current collectors.

  8. Research, development and demonstration in the design of sanitary landfill to optimize the generation and capture of compressible gas

    Science.gov (United States)

    Nosanov, M. E.; Teeple, F. E.; Buesch, S. C.

    1982-02-01

    The influences of selected factors on the generation and recovery of methane gas from sanitary landfills were investigated. The factors included encapsulation, shredding, air classifying, moisture, and pH. Facilities consisting of six model sanitary landfill cells, each with a capacity of approximately 450 cubic yards of municipal waste, and auxiliary subsystems were constructed. Municipal waste in each cell is contained in a 30-mil thick polyvinly chloride plastic sheeting forming a virtually gas-tight envelope. Two cells were filled with as-collected urban waste, two with shredded waste, and two with shredded and air classified waste, constituting three pairs of cells. One of each pair is a control cell with the other used as an experimental variable. Systems were provided for adding measured amounts of water, removing and recirculating leachate, and for extracting gas and measuring gas flow. During testing, gas production and internal cell characteristics were measured to determine the effects of mechanical processing, moisture content, and leachate pH.

  9. Environmental and human risk assessment of landfill leachate: An integrated approach with the use of cytotoxic and genotoxic stress indices in mussel and human cells

    Energy Technology Data Exchange (ETDEWEB)

    Toufexi, Eirini; Tsarpali, Vasiliki [Section of Animal Biology, Department of Biology, School of Natural Sciences, University of Patras, GR 26500 Patras (Greece); Efthimiou, Ioanna; Vidali, Maria-Sophia; Vlastos, Dimitris [Department of Environmental and Natural Resources Management, University of Patras, 2 Seferi Str., GR 30100 Agrinio (Greece); Dailianis, Stefanos, E-mail: sdailianis@upatras.gr [Section of Animal Biology, Department of Biology, School of Natural Sciences, University of Patras, GR 26500 Patras (Greece)

    2013-09-15

    Highlights: • Landfill leachate poses a threat for aquatic biota and humans. • Leachate induces cytotoxic and oxidative effects on mussel hemocytes. • Increased levels of DNA damage were observed both in vivo and in vitro in hemocytes. • Leachate low doses enhance MN formation in human lymphocyte cultures. • Potential leachate aneugenic activity was detected in human lymphocytes. -- Abstract: The present study investigates leachate hazardous effects on marine biota and human cells, with the use of a battery of assays, both under in vivo and in vitro conditions. According to the results, mussels exposed for 4 days to 0.01 and 0.1% (v/v) of leachate showed increased levels of DNA damage and micronuclei (MN) frequencies in their hemocytes. Similarly, enhanced levels of DNA damage were also observed in hemocytes treated in vitro with relevant concentrations of leachate, followed by a significant enhancement of both superoxide anions (·O{sub 2}{sup −}) and lipid peroxidation products (malondialdehyde/MDA). On the other hand, human lymphocyte cultures treated with such a low concentrations of leachate (0.1, 0.2 and 1%, v/v), showed increased frequencies of MN formation and large MN size ratio, as well as decreased cell proliferation, as indicated by the use of the cytokinesis block micronucleus (CBMN) assay and Cytokinesis Block Proliferation Index (CBPI) respectively. These findings showed the clear-cut genotoxic and cytotoxic effects of leachate on both cellular types, as well as its potential aneugenic activity in human lymphocytes.

  10. 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...

  11. Investigating Microbial Activity in Diazotrophic Methane Seep Sediment via Transcript Analysis and Single-Cell FISH-NanoSIMS

    Science.gov (United States)

    Dekas, A. E.; Connon, S. A.; Chadwick, G.; Orphan, V. J.

    2012-12-01

    Methane seep microbial ecosystems are phylogenetically diverse and physiologically complex, and require culture-independent techniques to accurately investigate metabolic activity. In the present study we combine an RNA analysis of four key microbial genes with FISH-NanoSIMS analysis of single cells to determine the diversity of nitrogen fixing microorganisms (diazotrophs) present at a deep-sea methane-seeping site, as well as investigate the methane-dependency of a variety of community members. Recently, methane-dependent nitrogen fixation was observed in Mound 12 Costa Rica sediments, and was spatially correlated with the abundance of aggregates of anaerobic methanotrophic archaea (ANME) and sulfate reducing bacterial symbionts (SRB). Combined with the detection of 15N uptake from 15N2 in these aggregates, this suggested that the ANME-SRB aggregates are the primary diazotrophs in seep sediment. However, the diversity of dinitrogenase reductase (nifH) sequences recovered from several deep-sea locales, including Mound 12, suggests a greater diversity of diazotrophs in marine sediment. To investigate the activity of these potential diazotrophs in Mound 12 sediment, we investigated a suite of RNA transcripts in 15N2 incubations in both the presence and absence of methane: nifH, bacterial 16S rRNA, methyl coenzyme M reductase A (mcrA), and adenosine-5'-phosposulfate reductase alpha subunit (aprA). No nifH transcripts were recovered in incubations without methane, consistent with previous measurements lacking 15N2 uptake in the same sediments. The activity of the bacterial community in general, assessed by variable transcription, was also greatly affected by the presence or absence of methane. Single-cell fluorescence in situ hybridization coupled to nanoscale secondary ion mass spectrometry (FISH-NanoSIMS) was employed to confirm diazotrophic activity (15N2 uptake) and protein synthesis (15NH4+ uptake) of particular species implicated as ecologically important by the

  12. Construction and evaluation of simulated pilot scale landfill lysimeter in Bangladesh.

    Science.gov (United States)

    Rafizul, Islam M; Howlader, Milon Kanti; Alamgir, Muhammed

    2012-11-01

    This research concentrates the design, construction and evaluation of simulated pilot scale landfill lysimeter at KUET campus, Khulna, Bangladesh. Both the aerobic and anaerobic conditions having a base liner and two different types of cap liner were simulated. After the design of a reference cell, the construction of landfill lysimeter was started in January 2008 and completed in July 2008. In all construction process locally available civil construction materials were used. The municipal solid waste (MSW) of 2800-2985 kg having the total volume of 2.80 m(3) (height 1.6 m) and moisture content of 65% was deposited in each lysimeter by applying required compaction energy. In contrast, both the composition in terms of methane (CH(4)), carbon dioxide (CO(2)) and oxygen (O(2)) as well as the flow rate of landfill gas (LFG) generated from MSW in landfill lysimeter were measured and varied significantly in relation to the variation of lysimeter operational condition. Moreover, anaerobic lysimeter-C shows the highest composition of LFG in compare to the anaerobic lysimeter-B due to the providing of lower compaction of cap liner in anaerobic lysimeter-C. Here, it is interesting to note that in absence of compacted clay liner (CCL) and hence percolation of rainwater that facilitates rapid degradation of MSW in aerobic lysimeter-A has resulted in the highest settlement than that of anaerobic landfill lysimeter-B and C. Moreover, in case of anaerobic lysimeter-B and C, the leachate generation was lower than that of aerobic lysimeter-A due to the providing of cap liner in anaerobic lysimeter-B and C, played an important role to reduce the percolation of rainwater. The study also reveals that the leachate pollution index (LPI) has decreased in relation to the increasing of elapsed period as well as the LPI for collection system of aerobic lysimeter-A was higher than that of the collection system of anaerobic lysimeter-B and C. Finally, it can be depicted that LPI for lysimeter

  13. Evaluation of an Odour Emission Factor (OEF) to estimate odour emissions from landfill surfaces

    Science.gov (United States)

    Lucernoni, Federico; Tapparo, Federica; Capelli, Laura; Sironi, Selena

    2016-11-01

    Emission factors are fundamental tools for air quality management. Odour Emission Factors (OEFs) can be developed in analogy with the emission factors defined for other chemical compounds, which relate the quantity of a pollutant released to the atmosphere to a given associated activity. Landfills typically represent a common source of odour complaint; for this reason, the development of specific OEFs allowing the estimation of odour emissions from this kind of source would be of great interest both for the landfill design and management. This study proposes an up-to-date methodology for the development of an OEF for the estimation of odour emissions from landfills, thereby focusing on the odour emissions related to the emissions of landfill gas (LFG) from the exhausted landfill surface. The proposed approach is an "indirect" approach based on the quantification of the LFG emissions from methane concentration measurements carried out on an Italian landfill. The Odour Emission Rate (OER) is then obtained by multiplying the emitted gas flow rate by the LFG odour concentration. The odour concentration of the LFG emitted through the landfill surface was estimated by means of an ad hoc correlation investigated between methane concentration and odour concentration. The OEF for the estimation of odour emissions from landfill surfaces was computed, considering the landfill surface as the activity index, as the product between the mean specific LFG flux emitted through the surface resulting from the experimental campaigns, equal to 0.39 l/m2/h, and its odour concentration, which was estimated to be equal to 105‧000 eq. ouE/m3, thus giving an OEF of 0.011 ouE/m2/s. This value, which is considerably lower than those published in previous works, should be considered as an improved estimation based on the most recent developments of the research in the field of odour sampling on surface sources.

  14. The decay of wood in landfills in contrasting climates in Australia.

    Science.gov (United States)

    Ximenes, Fabiano; Björdal, Charlotte; Cowie, Annette; Barlaz, Morton

    2015-07-01

    Wood products in landfill are commonly assumed to decay within several decades, returning the carbon contained therein to the atmosphere, with about half the carbon released as methane. However, the rate and extent of decay is not well known, as very few studies have examined the decay of wood products in landfills. This study reports on the findings from landfill excavations conducted in the Australian cities of Sydney and Cairns located in temperate and tropical environments, respectively. The objective of this study was to determine whether burial of the wood in warmer, more tropical conditions in Cairns would result in greater levels of decay than occurs in the temperate environment of Sydney. Wood samples recovered after 16-44years in landfill were examined through physical, chemical and microscopic analyses, and compared with control samples to determine the carbon loss. There was typically little or no decay in the wood samples analysed from the landfill in Sydney. Although there was significant decay in rainforest wood species excavated from Cairns, decay levels for wood types that were common to both Cairns and Sydney landfills were similar. The current Intergovernmental Panel on Climate Change (IPCC, 2006) default decay factor for organic materials in landfills is 50%. In contrast, the carbon loss determined for Pinus radiata recovered from Sydney and Cairns landfills was 7.9% and 4.4%, respectively, and 0% for Agathis sp. This suggests that climate did not influence decay, and that the more extensive levels of decay observed for some wood samples from Cairns indicates that those wood types were more susceptible to biodegradation. Microscopic analyses revealed that most decay patterns observed in samples analysed from Sydney were consistent with aerobic fungal decay. Only a minor portion of the microbial decay was due to erosion bacteria active in anaerobic/near anaerobic environments. The findings of this study strongly suggest that models that adopt

  15. Study of biogas production parameters in the sanitary landfill; Estudio de los parametros que afectan la produccion de biogas en un vertedero controlado

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez Domenech, G.; Gordillo Bolasell, M. A.; Sanchez Ferrer, A.

    2001-07-01

    The following article contents a study about some of the parameters affecting the evolution of the gas production in a sanitary landfill placed in the province of Barcelona. The work is focused on the quality of biogas produced, measured as the percentage of methane and thus its energy profitability. The parameters included in this paper are: -Situation of the gas extraction station -Age of the wastes. -Reinfiltration of concentrated liquid leachate in the considered cell. Among the previous factors, the situation of the gas station and the age of wastes showed a critical influence on the methane content, whereas the use of leachate reinfiltration did not produce significant differences in the quality of biogas in the short-term applications. (Author) 5 refs.

  16. 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.

  17. Energy utilization from landfill biogas; Aproveitamento energetico do biogas de aterros sanitarios

    Energy Technology Data Exchange (ETDEWEB)

    Candiani, Giovano [Universidade Federal do ABC, Santo Andre, SP (Brazil). Programa de Pos-Graduacao em Energia; Hoffmann, Gustavo; Silva, Elissandro Rocha da; Moreira, Joao M.L.; Tomioka, Jorge

    2008-07-01

    Landfills for solid waste disposal are used in Brazil and in most of countries in the world. The organic part of the solid wastes produces gas out of the decomposition of its organic content. This gas, named biogas and mostly made of carbon dioxide and methane, may be collected and used as an energy source due the methane presence. In this work we analyze the possible energy utilization of landfill biogas in Brazil in which the organic content of the solid waste is about 60%. The use of biogas as energy source can reduce the greenhouse gas emissions and improve the sanitation conditions of landfills. Moreover, it allows financial gains through selling of energy and carbon credits. In order to make possible the biogas utilization it is necessary to recognize the differences among the many landfills which exist in the country. There are the large and small landfills. The large ones usually have good instrumentation and gas exhaustion systems while the small ones have passive exhaustion systems and very few field instrumentation. The small landfills need to improve their instrumentation system and to incorporate exhaustion systems. (author)

  18. Protease cell wall degradation of Chlorella vulgaris: effect on methane production.

    Science.gov (United States)

    Mahdy, Ahmed; Mendez, Lara; Blanco, Saul; Ballesteros, Mercedes; González-Fernández, Cristina

    2014-11-01

    In order to optimize the enzymatic dosage and microalgae biomass loads subjected to enzymatic hydrolysis prior anaerobic digestion of Chlorella vulgaris, organic matter solubilisation and methane production were investigated. Experimental data using protease dosage of 0.585 AU g DW(-1) showed that increasing biomass loads up to 65 g L(-1) did not affect markedly the hydrolysis efficiency (51%). Enzymatically pretreated biomasses subjected to anaerobic digestion enhanced methane production by 50-70%. The attempt of decreasing the enzymatic dosages revealed diminished hydrolysis efficiency concomitantly with a decreased methane production enhancement. In agreement with the good results observed for organic matter conversion into biogas, total nitrogen mineralization was attained for enzymatically pretreated biomass. Despite the high protein content of the biomass and the biocatalyst used in the present study no ammonia inhibition was detected.

  19. Residential landfill remedial action construction case history

    Energy Technology Data Exchange (ETDEWEB)

    Creamer, P.D.; Martin, K.E. [RMT, Inc., Madison, WI (United States); Fahrney, J.S. [City of Madison, WI (United States)

    1995-12-31

    The City of Madison - Mineral Point Park is located on Madison`s west side within a well-established neighborhood on approximately 11 acres of open green space, which was formerly the Mineral Point Landfill. In 1994, a comprehensive remedial action construction project was implemented to more effectively extract methane gas and control gas migration, to minimize potential groundwater contamination, and to improve surface water run-off controls. This was accomplished by installing two new gas extraction systems, constructing a 4-foot-thick composite final cover with a geosynthetic subsurface drainage system, and adding 12 feet of relief and a storm sewer system to promote positive surface water drainage. While these features alone are not uncommon to many other landfills, the challenging aspect of this project was to install them in extreme proximity to homes, condominiums, and a school that were quickly developed shortly after the landfill closed. Some of the issues unique to this project due to the residential setting included strict noise, dust, and odor controls, easement negotiations, limited hours of operation, limited material storage areas, utility relocations and crossings, continuous operation of the existing gas extraction system, limited construction access, and increased health and safety concerns for the general public. The need to keep the neighboring residents informed, as well as to address their concerns and requests, was also a critical requirement in both the design and construction phases. This paper will review the design of the remedial action plan and present the construction process, highlighting the constructability issues encountered and the innovative means to overcome them. The program for communication with the neighbors throughout the design and construction phases will also be addressed.

  20. The decay of wood in landfills in contrasting climates in Australia

    Energy Technology Data Exchange (ETDEWEB)

    Ximenes, Fabiano, E-mail: fabiano.ximenes@dpi.nsw.gov.au [Forest Science, Agriculture NSW, New South Wales Department of Primary Industries, Level 12, 10 Valentine Ave, Parramatta, NSW 2150 (Australia); Björdal, Charlotte [Department of Conservation, Gothenburg University, Guldhedsgatan 5A, Box 130, SE-405 30 Göteborg (Sweden); Cowie, Annette [NSW Department of Primary Industries, Beef Industry Centre, Trevenna Rd., University of New England, Armidale, NSW 2351 (Australia); Barlaz, Morton [Dept. of Civil, Construction, & Environmental Eng., North Carolina State University, Box 7908, Raleigh, NC 27695-7908 (United States)

    2015-07-15

    Highlights: • We examine decay in wood from landfills in contrasting environments in Australia. • Analysis is based on changes in chemical composition and microscopy. • Climate did not influence levels of decay observed. • Microscopy of retrieved samples revealed most of the decay was aerobic in nature. • Current default factors for wood decay in landfills overestimate methane emissions. - Abstract: Wood products in landfill are commonly assumed to decay within several decades, returning the carbon contained therein to the atmosphere, with about half the carbon released as methane. However, the rate and extent of decay is not well known, as very few studies have examined the decay of wood products in landfills. This study reports on the findings from landfill excavations conducted in the Australian cities of Sydney and Cairns located in temperate and tropical environments, respectively. The objective of this study was to determine whether burial of the wood in warmer, more tropical conditions in Cairns would result in greater levels of decay than occurs in the temperate environment of Sydney. Wood samples recovered after 16–44 years in landfill were examined through physical, chemical and microscopic analyses, and compared with control samples to determine the carbon loss. There was typically little or no decay in the wood samples analysed from the landfill in Sydney. Although there was significant decay in rainforest wood species excavated from Cairns, decay levels for wood types that were common to both Cairns and Sydney landfills were similar. The current Intergovernmental Panel on Climate Change (IPCC, 2006) default decay factor for organic materials in landfills is 50%. In contrast, the carbon loss determined for Pinus radiata recovered from Sydney and Cairns landfills was 7.9% and 4.4%, respectively, and 0% for Agathis sp. This suggests that climate did not influence decay, and that the more extensive levels of decay observed for some wood samples

  1. Differences in volatile methyl siloxane (VMS) profiles in biogas from landfills and anaerobic digesters and energetics of VMS transformations

    Energy Technology Data Exchange (ETDEWEB)

    Tansel, Berrin, E-mail: tanselb@fiu.edu; Surita, Sharon C.

    2014-11-15

    Highlights: • In the digester gas, D4 and D5 comprised the 62% and 27% if siloxanes, respectively. • In landfill gas, the bulk of siloxanes were TMSOH (58%) followed by D4 (17%). • Methane utilization may be a possible mechanism for TMSOH formation in the landfills. • The geometric configurations of D4 and D5 molecules make them very stable. - Abstract: The objectives of this study were to compare the types and levels of volatile methyl siloxanes (VMS) present in biogas generated in the anaerobic digesters and landfills, evaluate the energetics of siloxane transformations under anaerobic conditions, compare the conditions in anaerobic digesters and municipal solid waste (MSW) landfills which result in differences in siloxane compositions. Biogas samples were collected at the South District Wastewater Treatment Plant and South Dade Landfill in Miami, Florida. In the digester gas, D4 and D5 comprised the bulk of total siloxanes (62% and 27%, respectively) whereas in the landfill gas, the bulk of siloxanes were trimethylsilanol (TMSOH) (58%) followed by D4 (17%). Presence of high levels of TMSOH in the landfill gas indicates that methane utilization may be a possible reaction mechanism for TMSOH formation. The free energy change for transformation of D5 and D4 to TMSOH either by hydrogen or methane utilization are thermodynamically favorable. Either hydrogen or methane should be present at relatively high concentrations for TMSOH formation which explains the high levels present in the landfill gas. The high bond energy and bond distance of the Si–O bond, in view of the atomic sizes of Si and O atoms, indicate that Si atoms can provide a barrier, making it difficult to break the Si–O bonds especially for molecules with specific geometric configurations such as D4 and D5 where oxygen atoms are positioned inside the frame formed by the large Si atoms which are surrounded by the methyl groups.

  2. Contribution by the methanogenic endosymbionts of anaerobic ciliates to methane production in Dutch freshwater sediments

    NARCIS (Netherlands)

    Hoek, van A.H.A.M.; Alen, T.A.; Vogels, G.D.; Hackstein, J.H.P.

    2006-01-01

    Biogenic methane contributes substantially to the atmospheric methane concentration and thus to global warming. This trace gas is predominantly produced by strictly anaerobic methanogenic archaea, which thrive in the most divergent ecological niches, e. g. paddy fields, sediments, landfills, and the

  3. Methane; the other greenhouse gas research and policy in the Netherlands

    NARCIS (Netherlands)

    Amstel AR van; Swart RJ; Krol MS; Beck JP; Bouman AF; Hoek KW van der

    1993-01-01

    The increase of anthropogenic activities is the main reason for the increase of methane emissions in the Netherlands. Methane is an important greenhouse gas. The most important sources in the Netherlands are landfills, cattle, manure and the exploration, transport and distribution of oil and gas. In

  4. Lidar Measurements of Methane and Applications for Aircraft and Spacecraft

    Science.gov (United States)

    Riris, Haris; Numata, Kenji; Abshire, James; Li, Steve; Wu, Stewart; Krainak, Michael; Sun, Xiaoli

    2010-01-01

    Atmospheric methane levels have remained relatively constant over the last decade around 1.78 parts per million (ppm) but observations since 2007 show that levels may be increasing. This trend may be caused by increased fossil fuel production, rice farming, livestock and landfills, but the underlying causes are quite uncertain. One hypothesis is that reservoirs of carbon trapped in the permafrost regions of northern Canada, Europe, and Siberia thaw as global temperatures rise and are releasing increasing amounts of methane. Another hypothesis points to increased production of methane by microbes as the permafrost warms. Currently most observations of greenhouse gases are limited to in-situ (surface and tower sites) and limited airborne in-situ measurements. Space column density measurements are starting to become available from the GOSAT mission. Although methane survives for a shorter time in the atmosphere than CO2, its impact on climate change per molecule is about 23 times than that of CO2. Accurate global observations of several greenhouse gases, including methane, are urgently needed in order to better understand climate change processes and to reduce the uncertainty in the carbon budget. Differential absorption lidar is a well-established technique to measure atmospheric gases, and methane has optical absorption bands near 1.65,2.2,3.4 and 7.8 micron. The near infrared overtones lines of CH4 near 1650 nm are relatively free of interference from other species. There are absorption lines near 1651 nm which are both temperature insensitive and have line strengths well suited for lidar measurements. We have developed a laser and demonstrated lidar measurements of CH4 using lines in this band. Our laser uses a narrow linewidth 1064 nm laser pulse passing through a nonlinear crystal. We generate the tunable laser signals near 1651 nm by using the optical parametric amplification (OPA) process. Inside the crystal the 1064 nm beam overlaps with an injection seed

  5. Attributing Atmospheric Methane to Anthropogenic Emission Sources.

    Science.gov (United States)

    Allen, David

    2016-07-19

    Methane is a greenhouse gas, and increases in atmospheric methane concentration over the past 250 years have driven increased radiative forcing of the atmosphere. Increases in atmospheric methane concentration since 1750 account for approximately 17% of increases in radiative forcing of the atmosphere, and that percentage increases by approximately a factor of 2 if the effects of the greenhouse gases produced by the atmospheric reactions of methane are included in the assessment. Because of the role of methane emissions in radiative forcing of the atmosphere, the identification and quantification of sources of methane emissions is receiving increased scientific attention. Methane emission sources include biogenic, geogenic, and anthropogenic sources; the largest anthropogenic sources are natural gas and petroleum systems, enteric fermentation (livestock), landfills, coal mining, and manure management. While these source categories are well-known, there is significant uncertainty in the relative magnitudes of methane emissions from the various source categories. Further, the overall magnitude of methane emissions from all anthropogenic sources is actively debated, with estimates based on source sampling extrapolated to regional or national scale ("bottom-up analyses") differing from estimates that infer emissions based on ambient data ("top-down analyses") by 50% or more. To address the important problem of attribution of methane to specific sources, a variety of new analytical methods are being employed, including high time resolution and highly sensitive measurements of methane, methane isotopes, and other chemical species frequently associated with methane emissions, such as ethane. This Account describes the use of some of these emerging measurements, in both top-down and bottom-up methane emission studies. In addition, this Account describes how data from these new analytical methods can be used in conjunction with chemical mass balance (CMB) methods for source

  6. Methylated mercury species in municipal waste landfill gas sampled in Florida, USA

    Science.gov (United States)

    Lindberg, S. E.; Wallschläger, D.; Prestbo, E. M.; Bloom, N. S.; Price, J.; Reinhart, D.

    Mercury-bearing material has been placed in municipal landfills from a wide array of sources including fluorescent lights, batteries, electrical switches, thermometers, and general waste. Despite its known volatility, persistence, and toxicity in the environment, the fate of mercury in landfills has not been widely studied. The nature of landfills designed to reduce waste through generation of methane by anaerobic bacteria suggests the possibility that these systems might also serve as bioreactors for the production of methylated mercury compounds. The toxicity of such species mandates the need to determine if they are emitted in municipal landfill gas (LFG). In a previous study, we had measured levels of total gaseous mercury (TGM) in LFG in the μg/m 3 range in two Florida landfills, and elevated levels of monomethyl mercury (MMM) were identified in LFG condensate, suggesting the possible existence of gaseous organic Hg compounds in LFG. In the current study, we measured TGM, Hg 0, and methylated mercury compounds directly in LFG from another Florida landfill. Again, TGM was in the μg/m 3 range, MMM was found in condensate, and this time we positively identified dimethyl mercury (DMM) in the LGF in the ng/m 3 range. These results identify landfills as a possible anthropogenic source of DMM emissions to air, and may help explain the reports of MMM in continental rainfall.

  7. 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.

  8. Isolation of methanotrophic bacteria from a london landfill: a preliminary study using molecular and stable isotopic techniques.

    Science.gov (United States)

    Sriskantharajah, S.; Cutting, S.; Lowry, D.; Grassineau, N.; Nisbet, E.

    2003-04-01

    Methane emissions from landfills are an important source of European greenhouse emissions, and could be reduced by a biological management program that used methanotrophs in landfill cover soils. Topsoil samples taken from a London Landfill were incubated on Nitrate Mineral Salts medium in the presence of methane. The resulting colonies were probed for methanotrophic DNA using PCR amplification. DNA from methanotroph positive colonies was cloned and sequenced for identification. Isolates belonging to the genera Methylocaldum, Methylomonas and Methylosinus were detected. Phylogenetic analysis suggests the presence of possible new species. In addition dried samples of the isolates were analysed for their stable carbon isotope (δ 13C) composition. The results were δ 13C values of -27 per mil and -25 per mil for Methylomonas isolates, -35 per mil and -44 per mil for Methylosinus isolates, -58 per mil and -60 per mil for some of the Methylocaldum isolates and -35 per mil and -45 per mil for the others. This isotopic variation is reflected in a phylogenetic tree of the isolates. The differences shown in the δ 13C analysis could be due to differing biochemical properties, and if the technique is further developed, it may be used for rapid identification of bacteria useful in landfill management for reducing methane emissions. The results suggest that useful reductions in methane emissions could be achieved by a careful design of landfill cover to culture methanotrophs.

  9. Landfill Construction and Capacity Expansion

    NARCIS (Netherlands)

    Andre, F.J.; Cerda, E.

    2003-01-01

    We study the optimal capacity and lifetime of landfills taking into account their sequential nature.Such an optimal capacity is characterized by the so-called Optimal Capacity Condition.Particular versions of this condition are obtained for two alternative settings: first, if all the landfills are t

  10. Process for separating nitrogen from methane using microchannel process technology

    Science.gov (United States)

    Tonkovich, Anna Lee; Qiu, Dongming; Dritz, Terence Andrew; Neagle, Paul; Litt, Robert Dwayne; Arora, Ravi; Lamont, Michael Jay; Pagnotto, Kristina M.

    2007-07-31

    The disclosed invention relates to a process for separating methane or nitrogen from a fluid mixture comprising methane and nitrogen, the process comprising: (A) flowing the fluid mixture into a microchannel separator, the microchannel separator comprising a plurality of process microchannels containing a sorption medium, the fluid mixture being maintained in the microchannel separator until at least part of the methane or nitrogen is sorbed by the sorption medium, and removing non-sorbed parts of the fluid mixture from the microchannel separator; and (B) desorbing the methane or nitrogen from the sorption medium and removing the desorbed methane or nitrogen from the microchannel separator. The process is suitable for upgrading methane from coal mines, landfills, and other sub-quality sources.

  11. Kinetics of methane oxidation in selected mineral soils

    Science.gov (United States)

    Walkiewicz, A.; Bulak, P.; Brzeziñska, M.; Włodarczyk, T.; Polakowski, C.

    2012-10-01

    The kinetic parameters of methane oxidation in three mineral soils were measured under laboratory conditions. Incubationswere preceded by a 24-day preincubationwith 10%vol. of methane. All soils showed potential to the consumption of added methane. None of the soils, however, consumed atmospheric CH4. Methane oxidation followed the Michaelis-Menten kinetics, with relatively low values of parameters for Eutric Cambisol, while high values for Haplic Podzol, and especially for Mollic Gleysol which showed the highest methanotrophic activity and much lower affinity to methane. The high values of parameters for methane oxidation are typical for organic soils and mineral soils from landfill cover. The possibility of the involvement of nitrifying microorganisms, which inhabit the ammonia-fertilized agricultural soils should be verified.

  12. Biogeochemistry and isotope geochemistry of a landfill leachate plume.

    Science.gov (United States)

    van Breukelen, Boris M; Röling, Wilfred F M; Groen, Jacobus; Griffioen, Jasper; van Verseveld, Henk W

    2003-09-01

    The biogeochemical processes were identified which improved the leachate composition in the flow direction of a landfill leachate plume (Banisveld, The Netherlands). Groundwater observation wells were placed at specific locations after delineating the leachate plume using geophysical tests to map subsurface conductivity. Redox processes were determined using the distribution of solid and soluble redox species, hydrogen concentrations, concentration of dissolved gases (N(2), Ar, and CH(4)), and stable isotopes (delta15N-NO(3), delta34S-SO(4), delta13C-CH(4), delta2H-CH(4), and delta13C of dissolved organic and inorganic carbon (DOC and DIC, respectively)). The combined application of these techniques improved the redox interpretation considerably. Dissolved organic carbon (DOC) decreased downstream in association with increasing delta13C-DOC values confirming the occurrence of degradation. Degradation of DOC was coupled to iron reduction inside the plume, while denitrification could be an important redox process at the top fringe of the plume. Stable carbon and hydrogen isotope signatures of methane indicated that methane was formed inside the landfill and not in the plume. Total gas pressure exceeded hydrostatic pressure in the plume, and methane seems subject to degassing. Quantitative proof for DOC degradation under iron-reducing conditions could only be obtained if the geochemical processes cation exchange and precipitation of carbonate minerals (siderite and calcite) were considered and incorporated in an inverse geochemical model of the plume. Simulation of delta13C-DIC confirmed that precipitation of carbonate minerals happened.

  13. 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

  14. Methane oxidation at redox stable fuel cell electrode La0.75Sr0.25Cr0.5Mn0.5O(3-delta).

    Science.gov (United States)

    Tao, Shanwen; Irvine, John T S; Plint, Steven M

    2006-11-02

    Because of its widespread availability, natural gas is the most important fuel for early application of stationary fuel cells, and furthermore, methane containing biogases are one of the most promising renewable energy alternatives; thus, it is very important to be able to efficiently utilize methane in fuel cells. Typically, external steam reforming is applied to allow methane utilization in high temperature fuel cells; however, direct oxidation will provide a much better solution. Recently, we reported good electrochemical performance for an oxide anode La0.75Sr0.25Cr0.5Mn0.5O3 (LSCM) in low moisture (3% H2O) H2 and CH4 fuels without significant coking in CH4. Here, we investigate the catalytic activity of this oxide with respect to its ability to utilize methane. This oxide is found to exhibit fairly low reforming activity for both H2O and CO2 reforming but is active for methane oxidation. LSCM is found to be a full oxidation catalyst rather than a partial oxidation catalyst as CO2 production dominates CO production even in CH4-rich CH4/O2 mixtures. X-ray adsorption spectroscopy was utilized to confirm that Mn was the redox active species, clearly demonstrating that this material has the oxidation catalytic behavior that might be expected from a Mn perovskite and that the Cr ion is only present to ensure stability under fuel atmospheres.

  15. ENGINEERING ASPECTS OF LANDFILLING MUNICIPAL SOLID WASTE

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Sanitary landfilling is the most important method of municipalsolid waste disposal in China. Landfill sites are always set up in mountain valley, on plain or beside seashore. A complete landfill consists of base system, cover system, and leachate collection and gas extraction system. This paper reviews the state-of-the-art landfilling technology in China and collection discusses research projects for engineers.

  16. Assessing Emissions of Volatile Organic Componds from Landfills Gas

    Directory of Open Access Journals (Sweden)

    Fahime Khademi

    2016-01-01

    Full Text Available Background: Biogas is obtained by anaerobic decomposition of organic wastes buried materials used to produce electricity, heat and biofuels. Biogas is at the second place for power generation after hydropower and in 2000 about 6% of the world power generation was allocated to biogas. Biogas is composed of 40–45 vol% CO2, 55–65 vol% CH4, and about 1% non-methaneVOCs, and non-methane volatile organic compounds. Emission rates are used to evaluate the compliance with landfill gas emission regulations by the United States Environmental Protection Agency (USEPA. BTEX comounds affect the air quality and may be harmful to human health. Benzene, toluene, ethylbenzene and xylene isomers that are generally called BTEX compounds are the most abundant VOCs in biogas. Methods: Sampling of VOCs in biogas vents was operated passively or with Tedlar bags. 20 samples were collected from 40 wells of old and new biogas sites of Shiraz’ landfill. Immediately after sampling, the samples were transferred to the laboratory. Analysis of the samples was performed with GC-MS. Results: The results showed that in the collection of the old and new biogas sites, the highest concentration of VOCs was observed in toluene (0.85ppm followed by benzene (0.81ppm, ethylbenzene (0.13ppm and xylene (0.08ppm. Conclusion: The results of the study showed that in all samples, most available compounds in biogas vents were aromatic hydrocarbon compounds.These compounds’ constituents originate from household hazardous waste materials deposited in the landfill or from biological/chemical decomposition processes within the landfill.

  17. Decomposition and carbon storage of hardwood and softwood branches in laboratory-scale landfills

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaoming, E-mail: wangxiaoming@cqu.edu.cn [Key Laboratory of Three Gorges Reservoir Region' s Eco-Environment under Ministry of Education, Chongqing University, Chongqing 400044 (China); Department of Civil, Construction, and Environmental Engineering, Campus Box 7908, North Carolina State University, Raleigh, NC 27695-7908 (United States); Barlaz, Morton A. [Department of Civil, Construction, and Environmental Engineering, Campus Box 7908, North Carolina State University, Raleigh, NC 27695-7908 (United States)

    2016-07-01

    Tree branches are an important component of yard waste disposed in U.S. municipal solid waste (MSW) landfills. The objective of this study was to characterize the anaerobic biodegradability of hardwood (HW) and softwood (SW) branches under simulated but optimized landfill conditions by measuring methane (CH{sub 4}) yields, decay rates, the decomposition of cellulose, hemicellulose and organic carbon, as well as carbon storage factors (CSFs). Carbon conversions to CH{sub 4} and CO{sub 2} ranged from zero to 9.5% for SWs and 17.1 to 28.5% for HWs. When lipophilic or hydrophilic compounds present in some of the HW and SW samples were extracted, some samples showed increased biochemical methane potentials (BMPs). The average CH{sub 4} yield, carbon conversion, and CSF measured here, 59.4 mL CH{sub 4} g{sup −1} dry material, 13.9%, and 0.39 g carbon stored g{sup −1} dry material, respectively, represent reasonable values for use in greenhouse gas inventories in the absence of detailed wood type/species data for landfilled yard waste. - Highlights: • Characterized biodegradation of branches under simulated but optimized landfill conditions • Observed varied biodegradation between HW and SW branches with different diameters • Inhibitory extractives were observed on boughs or twigs of some branch species. • CH{sub 4} yield and carbon storage factors presented for use in landfill related inventories.

  18. Stable isotope signatures for characterising the biological stability of landfilled municipal solid waste.

    Science.gov (United States)

    Wimmer, Bernhard; Hrad, Marlies; Huber-Humer, Marion; Watzinger, Andrea; Wyhlidal, Stefan; Reichenauer, Thomas G

    2013-10-01

    Stable isotopic signatures of landfill leachates are influenced by processes within municipal solid waste (MSW) landfills mainly depending on the aerobic/anaerobic phase of the landfill. We investigated the isotopic signatures of δ(13)C, δ(2)H and δ(18)O of different leachates from lab-scale experiments, lysimeter experiments and a landfill under in situ aeration. In the laboratory, columns filled with MSW of different age and reactivity were percolated under aerobic and anaerobic conditions. In landfill simulation reactors, waste of a 25year old landfill was kept under aerobic and anaerobic conditions. The lysimeter facility was filled with mechanically shredded fresh waste. After starting of the methane production the waste in the lysimeter containments was aerated in situ. Leachate and gas composition were monitored continuously. In addition the seepage water of an old landfill was collected and analysed periodically before and during an in situ aeration. We found significant differences in the δ(13)C-value of the dissolved inorganic carbon (δ(13)C-DIC) of the leachate between aerobic and anaerobic waste material. During aerobic degradation, the signature of δ(13)C-DIC was mainly dependent on the isotopic composition of the organic matter in the waste, resulting in a δ(13)C-DIC of -20‰ to -25‰. The production of methane under anaerobic conditions caused an increase in δ(13)C-DIC up to values of +10‰ and higher depending on the actual reactivity of the MSW. During aeration of a landfill the aerobic degradation of the remaining organic matter caused a decrease to a δ(13)C-DIC of about -20‰. Therefore carbon isotope analysis in leachates and groundwater can be used for tracing the oxidation-reduction status of MSW landfills. Our results indicate that monitoring of stable isotopic signatures of landfill leachates over a longer time period (e.g. during in situ aeration) is a powerful and cost-effective tool for characterising the biodegradability and

  19. Evaluation and analysis of gaseous emission in landfill area and estimation of its pollutants dispersion, (case of Rodan in Hormozgan, Iran

    Directory of Open Access Journals (Sweden)

    Amirreza Talaiekhozani

    2016-08-01

    Full Text Available Background: The biogases are the mixture of gases produced through the microbial decomposition of organic waste which are amply observed in the landfills. The main purpose of this study was to estimate the emission rates of landfill gases such as carbon dioxide, methane and non-methane organic compounds (NMOCs in the solid waste landfill of Rodan city in Hormozgan province. Methods: All the necessary information such as population, geographic and climate of Rodan city were collected. Solid waste analysis was then conducted. Afterward, the LandGEM software is used in this study for the purpose of estimation of total biogas, methane, carbon dioxide and NMOCs emission from Rodan’s landfill. Results: The analysis of results showed that only 24.18% of the produced waste in this city is perishable. The calculations indicate that the peak of biogas production which is equal to 420 tons per year would be achieved in the year 2019. The production rates of carbon dioxide and methane in the same year would be equal to 308 and 112 tons per year respectively. The pollutants transmittance calculations in the vicinity of the landfill revealed that the maximum pollutant concentration is within the maximum distance of 200 m. Conclusion: The results obtained in this study could be used for the purpose of design and installation of extraction or incineration equipment in the landfill of Rodan.

  20. Vertical profiles of community abundance and diversity of anaerobic methanotrophic archaea (ANME) and bacteria in a simple waste landfill in north China.

    Science.gov (United States)

    Dong, Jun; Ding, Linjie; Wang, Xu; Chi, Zifang; Lei, Jiansen

    2015-03-01

    Anaerobic methane oxidation (AMO) is considered to be an important sink of CH4 in habitats as marine sediments. But, few studies focused on AMO in landfills which may be an important sink of CH4 derived from waste fermentation. To show evidence of AMO and to uncover function anaerobic methanotroph (ANME) community in landfill, different age waste samples were collected in Jinqianpu landfill located in north China. Through high-throughput sequencing, Methanomicrobiales and Methanosarcinales archaea associated with ANME and reverse methanogenic archaea of Methanosarcina and Methanobacterium were detected. Sulfate-reducing bacteria (SRB) (Desulfobulbus and Desulfococcus) which could couple with ANME-conducting AMO were also found. But, the community structure of ANME had no significant difference with depths. From the results of investigation, we can come to a conclusion that sulfate-dependent anaerobic methane oxidation (SR-DAMO) would be the dominant AMO process in the landfill, while iron-dependent anaerobic methane oxidation (M/IR-DAMO) process was weak though concentration of ferric iron was large in the landfill. Denitrification-dependent anaerobic methane oxidation (NR-DAMO) was negative because of lack of nitrate and relevant function microorganisms in the landfill. Results also indicate that CH4 mitigation would have higher potential by increasing electron acceptor contents and promoting the growth of relevant function microorganisms.

  1. Characterization, Concentrations and Emission Rates of Volatile Organic Compounds from Two Major Landfill Sites in Kuwait

    Directory of Open Access Journals (Sweden)

    Mohammad AlAhmad

    2012-01-01

    Full Text Available Problem statement: The emission of pollutants from landfill sites in Kuwait is of major concern due to the associated adverse environmental and health impacts. There are 18 landfill sites in Kuwait which are contributing to the emission of atmospheric pollutants including; methane, carbon dioxide and Volatile Organic Compounds (VOCs. Approach: Determine the concentration and composition of VOCs in LFG emissions from two major landfill sites in Kuwait and to investigate the influence of the "In-Situ Aerobic Stabilization" on the reduction of VOCs emission. VOCs samples were collected during an intensive, short-term field sampling campaign conducted in 2010 where 50 individual volatile organic compounds were identified and quantified in landfill gas samples collected from the two landfill sites and the Project Area. Results: The concentration levels of VOCs were found to be significantly different within the same landfill site; however, the average total VOCs emissions were comparable between the two landfill sites. Concentration of total VOCs (i.e., sum of 50 compounds in LFG emissions varied between 9.4-67.2 ppm in Jleeb Al-Shuyoukh landfill site and from 15.4-57.7 ppm in Al-Qurain landfill site. Annual emissions of the well-known five VOCs (i.e., benzene, toluene, ethylbenzene, m-, o- and p-xylenes and styrene were also computed for each vent pipe from Jleeb Al-Shuyoukh landfill using the measured average concentrations and LFG flow rates. The results, if calculated in terms of the average ΣBTEX+S quantity emitted per vent pipe per year, showed that the magnitude of ΣBTEX+S emissions ranged between 0.108 -11.686 g y−1. Conclusion: The results of this pilot project demonstrated that the “in-situ aerobic stabilization method” applied on old solid waste deposits in the project area of Jleeb Al-Shuyoukh landfill can significantly reduce the average VOCs concentration in LFG emissions from high-productivity wells in the project

  2. Biochemically enhanced methane production from coal

    Science.gov (United States)

    Opara, Aleksandra

    For many years, biogas was connected mostly with the organic matter decomposition in shallow sediments (e.g., wetlands, landfill gas, etc.). Recently, it has been realized that biogenic methane production is ongoing in many hydrocarbon reservoirs. This research examined microbial methane and carbon dioxide generation from coal. As original contributions methane production from various coal materials was examined in classical and electro-biochemical bench-scale reactors using unique, developed facultative microbial consortia that generate methane under anaerobic conditions. Facultative methanogenic populations are important as all known methanogens are strict anaerobes and their application outside laboratory would be problematic. Additional testing examined the influence of environmental conditions, such as pH, salinity, and nutrient amendments on methane and carbon dioxide generation. In 44-day ex-situ bench-scale batch bioreactor tests, up to 300,000 and 250,000 ppm methane was generated from bituminous coal and bituminous coal waste respectively, a significant improvement over 20-40 ppm methane generated from control samples. Chemical degradation of complex hydrocarbons using environmentally benign reagents, prior to microbial biodegradation and methanogenesis, resulted in dissolution of up to 5% bituminous coal and bituminous coal waste and up to 25% lignite in samples tested. Research results confirm that coal waste may be a significant underutilized resource that could be converted to useful fuel. Rapid acidification of lignite samples resulted in low pH (below 4.0), regardless of chemical pretreatment applied, and did not generate significant methane amounts. These results confirmed the importance of monitoring and adjusting in situ and ex situ environmental conditions during methane production. A patented Electro-Biochemical Reactor technology was used to supply electrons and electron acceptor environments, but appeared to influence methane generation in a

  3. Landfill aeration for emission control before and during landfill mining.

    Science.gov (United States)

    Raga, Roberto; Cossu, Raffaello; Heerenklage, Joern; Pivato, Alberto; Ritzkowski, Marco

    2015-12-01

    The landfill of Modena, in northern Italy, is now crossed by the new high velocity railway line connecting Milan and Bologna. Waste was completely removed from a part of the landfill and a trench for the train line was built. With the aim of facilitating excavation and further disposal of the material extracted, suitable measures were defined. In order to prevent undesired emissions into the excavation area, the aerobic in situ stabilisation by means of the Airflow technology took place before and during the Landfill Mining. Specific project features involved the pneumatic leachate extraction from the aeration wells (to keep the leachate table low inside the landfill and increase the volume of waste available for air migration) and the controlled moisture addition into a limited zone, for a preliminary evaluation of the effects on process enhancement. Waste and leachate were periodically sampled in the landfill during the aeration before the excavation, for quality assessment over time; the evolution of biogas composition in the landfill body and in the extraction system for different plant set-ups during the project was monitored, with specific focus on uncontrolled migration into the excavation area. Waste biological stability significantly increased during the aeration (waste respiration index dropped to 33% of the initial value after six months). Leachate head decreased from 4 to 1.5m; leachate recirculation tests proved the beneficial effects of moisture addition on temperature control, without hampering waste aerobization. Proper management of the aeration plant enabled the minimization of uncontrolled biogas emissions into the excavation area.

  4. PERFORMA OKSIDASI METAN PADA REAKTOR KONTINYU DENGAN PENINGKATAN KETEBALAN LAPISAN BIOCOVER LANDFILL

    Directory of Open Access Journals (Sweden)

    Opy Kurniasari

    2013-11-01

    Full Text Available PERFORMANCE OF METHANE OXIDATION IN CONTINUOUS REACTOR BY BIOCOVER LANDFILL FILM THICKNESS IMPROVEMENT. Municipal solid waste (MSW handling in Indonesia is currently highly dependent on landfilling at the final disposal facility (TPA, which generally operated in layer-by-layer basis, allowing the anaerobic (absent of oxygen process. This condition will certainly generate biogas in the form of methane (CH4 and CO2. Methane is a greenhouse gas with a global warming potential greater than CO2, and can absorb infrared radiation 23 times more efficient than CO2 in the period of over 100 years. One way that can be done to reduce methane gas from landfills that escape into nature is to oxidize methane by utilizing landfill cover material (biocover as methane-oxidizing microorganism media. Application of compost as landfill cover material is a low-cost approach to reduce emissions so are suitable for developing countries. The compost used in this study was compost landfill mining, which is degraded naturally in landfill. The purpose of this study was to evaluate the ability of biocover to oxidize the methane on a certain layer thickness with a continuous flow conditions. Three column reactors were used, which were made of flexy glass measuring 70 cm in high and 15 cm in diameter. The methane flowed from the bottom of the reactor continuously at a flow rate of 5 ml/minute. The columns were filled with biocover compost landfill mining with layer thickness of 5, 25, 35 and 60 cm. The results showed that the thicker layer of biocover, the higher the efficiency of methane oxidation. The oxidation efficiency obtained in each layer thickness of 15, 25, 35 and 60 cm was 56.43%, 63.69%, 74.58% and 80, 03% respectively, with the rate of oxidation of 0.29 mol m-2 d-1 and the fraction of oxidation of 99%. The oxidation result was supported by the identification of bacteria isolated in this experiment, namely metanotrophic bacteria that have the ability to oxidize

  5. Anticancer activity of synthetic bis(indolyl)methane-ortho-biaryls against human cervical cancer (HeLa) cells.

    Science.gov (United States)

    Jamsheena, Vellekkatt; Shilpa, Ganesan; Saranya, Jayaram; Harry, Nissy Ann; Lankalapalli, Ravi Shankar; Priya, Sulochana

    2016-03-05

    Bis(indolyl)methane appended biaryls were designed, synthesized and evaluated in human cervical cancer cell lines (HeLa) for their anticancer activities and compared against normal rat cardiac myoblasts (H9C2) cells. Compounds 1-12 were synthesized, with variations in one of the phenyl unit, in a single step by condensation of biaryl-2-carbaldehydes with indole in the presence of para-toluenesulfonic acid. Compound 1 exhibited a GI50 value of 11.00 ± 0.707 μM and the derivatives, compounds 4 and 11 showed a GI50 value of 8.33 ± 0.416 μM and 9.13 ± 0.177 μM respectively in HeLa cells and was found to be non-toxic to H9C2 cells up to 20 μM. Furthermore, compounds 1, 4 and 11 induced caspase dependent cellular apoptosis in a concentration-dependent manner, reduced mitochondrial membrane potential, inhibited the cell migration and downregulated the production of MMP-2 and MMP-9 in HeLa cells.

  6. Internal short circuit and accelerated rate calorimetry tests of lithium-ion cells: Considerations for methane-air intrinsic safety and explosion proof/flameproof protection methods

    OpenAIRE

    Dubaniewicz, Thomas H.; DuCarme, Joseph P.

    2016-01-01

    Researchers with the National Institute for Occupational Safety and Health (NIOSH) studied the potential for lithium-ion cell thermal runaway from an internal short circuit in equipment for use in underground coal mines. In this third phase of the study, researchers compared plastic wedge crush-induced internal short circuit tests of selected lithium-ion cells within methane (CH4)-air mixtures with accelerated rate calorimetry tests of similar cells. Plastic wedge crush test results with meta...

  7. THE "CHEMICAL OXYGEN DEMAND / TOTAL VOLATILE ACIDS" RATIO AS AN ANAEROBIC TREATABILITY INDICATOR FOR LANDFILL LEACHATES

    Directory of Open Access Journals (Sweden)

    R. C. Contrera

    2015-03-01

    Full Text Available Abstract In some operational circumstances a fast evaluation of landfill leachate anaerobic treatability is necessary, and neither Biochemical Methane Potential nor BOD/COD ratio are fast enough. Looking for a fast indicator, this work evaluated the anaerobic treatability of landfill leachate from São Carlos-SP (Brazil in a pilot scale Anaerobic Sequence Batch Biofilm Reactor (AnSBBR. The experiment was conducted at ambient temperature in the landfill area. After the acclimation, at a second stage of operation, the AnSBBR presented efficiency above 70%, in terms of COD removal, utilizing landfill leachate without water dilution, with an inlet COD of about 11,000 mg.L-1, a TVA/COD ratio of approximately 0.6 and reaction time equal to 7 days. To evaluate the landfill leachate biodegradability variation over time, temporal profiles of concentration were performed in the AnSBBR. The landfill leachate anaerobic biodegradability was verified to have a direct and strong relationship to the TVA/COD ratio. For a TVA/CODTotal ratio lower than 0.20, the biodegradability was considered low, for ratios between 0.20 and 0.40 it was considered medium, and above 0.40 it was considered high.

  8. Assessing the role of spatial structure on cell-specific activity and interactions within uncultured methane-oxidizing syntrophic consortia (Invited)

    Science.gov (United States)

    Orphan, V. J.; McGlynn, S.; Chadwick, G.; Dekas, A.; Green-Saxena, A.

    2013-12-01

    Sulfate-coupled anaerobic oxidation of methane is catalysed through symbiotic associations between archaea and sulphate-reducing bacteria and represents the dominant sink for methane in the oceans. These methane-oxidizing symbiotic consortia form well-structured multi-celled aggregations in marine methane seeps, where close spatial proximity is believed to be essential for efficient exchange of substrates between syntrophic partners. The nature of this interspecies metabolic relationship is still unknown however there are a number of hypotheses regarding the electron carrying intermediate and ecophysiology of the partners, each of which should be affected by, and influence, the spatial arrangement of archaeal and bacterial cells within aggregates. To advance our understanding of the role of spatial structure within naturally occurring environmental consortia, we are using spatial statistical methods combined with fluorescence in situ hybridization and high-resolution nanoscale secondary ion mass spectrometry (FISH-nanoSIMS) to quantify the effect of spatial organization and intra- and inter-species interactions on cell-specific microbial activity within these diverse archaeal-bacterial partnerships.

  9. Application of Deuterium and Oxygen-18 to Trace Leachate Movement in Bantar Gebang Sanitary Landfill

    Directory of Open Access Journals (Sweden)

    E.R. Pujiindiyati

    2011-08-01

    Full Text Available Bantar Gebang landfill was constructed in 1986 with total area of 108 ha and approximately 6000 ton/day solid waste is disposed to this landfill. Mostly, the people living surrounding landfill get afraid of impact of the hazardous chemicals produced by waste disposal to their health. The purpose of this investigation was to study the migration of leachate to Cibitung River water and shallow groundwaters near to the river. It is possible to be done because chemical contents and isotopic characteristics of municipal landfill leachate are unique, relative to aqueous media in the most natural environments. Laser absorption method developed by the LGR (Los Gatos Research was used to measure absolute abundances of 2HHO, HH18O and HHO in a number of water samples. In-situ measurements were also conducted as an additional parameter besides their isotopes. The δ2H of the H2O in landfill leachate was significantly enriched, with values of - 22.6 ‰ to + 4.3 ‰. This deuterium enrichment was undoubtedly due to the extensive production of microbial methane within the limited reservoir of the landfill. However, the enriched deuterium value in leachate was not detected in the river which still had depleted values. It was probably caused by the amount of natural water in the river was comparatively large, with respect to limited leachate discarded to the river.The electrical conductivity of the leachate was higher (3200 to 7600 S and the decreasing values were still monitored in the river to approximately 12 km after streaming the landfills. The effect of the high electrical conductivity and enriched deuterium of leachate was not clearly indicated in the groundwater samples which still represented the local precipitation recharge, except a monitoring well located in Bantar Gebang landfill area which has an indication of leachate contamination.

  10. [Culturable psychrotolerant methanotrophic bacteria in landfill cover soil].

    Science.gov (United States)

    Kallistova, A Iu; Montonen, L; Jurgens, G; Munster, U; Kevbrina, M V; Nozhevnikova, A N

    2014-01-01

    Methanotrophs closely related to psychrotolerant members of the genera Methylobacter and Methylocella were identified in cultures enriched at 10@C from landfill cover soil samples collected in the period from April to November. Mesophilic methanotrophs of the genera Methylobacter and Methylosinus were found in cultures enriched at 20 degrees C from the same cover soil samples. A thermotolerant methanotroph related to Methylocaldum gracile was identified in the culture enriched at 40 degrees C from a sample collected in May (the temperature of the cover soil was 11.5-12.5 degrees C). In addition to methanotrophs, methylobacteria of the genera Methylotenera and Methylovorus and members of the genera Verrucomicrobium, Pseudomonas, Pseudoxanthomonas, Dokdonella, Candidatus Protochlamydia, and Thiorhodospira were also identified in the enrichment cultures. A methanotroph closely related to the psychrotolerant species Methylobacter tundripaludum (98% sequence identity of 16S r-RNA genes with the type strain SV96(T)) was isolated in pure culture. The introduction of a mixture of the methanotrophic enrichments, grown at 15 degrees C, into the landfill cover soil resulted in a decrease in methane emission from the landfill surface in autumn (October, November). The inoculum used was demonstrated to contain methanotrophs closely related to Methylobacter tundripaludum SV96.

  11. An experimental study with bioreactor-landfill system%生物反应器填埋场的试验研究

    Institute of Scientific and Technical Information of China (English)

    王君琴; 沈东升

    2003-01-01

    In this study, a methane bioreactor-landfill system was utilized to treat municipal solid waste (MSW). Through analyzing and detecting the pollutant(CODcr) in the bioreactor-landfill system, a simulated mathematic formulaof waste degradation was established. After treated with this system, the CODcr and VFA concentrations in MSW could be decreased from more than 20000 and 7000 mg·L-1 to less than 1500 and 200 mg·L-1, respec-tively.

  12. Reduction of Non-CO2 Gas Emissions Through The In Situ Bioconversion of Methane

    Energy Technology Data Exchange (ETDEWEB)

    Scott, A R; Mukhopadhyay, B; Balin, D F

    2012-09-06

    The primary objectives of this research were to seek previously unidentified anaerobic methanotrophs and other microorganisms to be collected from methane seeps associated with coal outcrops. Subsurface application of these microbes into anaerobic environments has the potential to reduce methane seepage along coal outcrop belts and in coal mines, thereby preventing hazardous explosions. Depending upon the types and characteristics of the methanotrophs identified, it may be possible to apply the microbes to other sources of methane emissions, which include landfills, rice cultivation, and industrial sources where methane can accumulate under buildings. Finally, the microbes collected and identified during this research also had the potential for useful applications in the chemical industry, as well as in a variety of microbial processes. Sample collection focused on the South Fork of Texas Creek located approximately 15 miles east of Durango, Colorado. The creek is located near the subsurface contact between the coal-bearing Fruitland Formation and the underlying Pictured Cliffs Sandstone. The methane seeps occur within the creek and in areas adjacent to the creek where faulting may allow fluids and gases to migrate to the surface. These seeps appear to have been there prior to coalbed methane development as extensive microbial soils have developed. Our investigations screened more than 500 enrichments but were unable to convince us that anaerobic methane oxidation (AMO) was occurring and that anaerobic methanotrophs may not have been present in the samples collected. In all cases, visual and microscopic observations noted that the early stage enrichments contained viable microbial cells. However, as the levels of the readily substrates that were present in the environmental samples were progressively lowered through serial transfers, the numbers of cells in the enrichments sharply dropped and were eliminated. While the results were disappointing we acknowledge that

  13. A robust NiO-Sm0.2Ce0.8O1.9 anode for direct-methane solid oxide fuel cell

    KAUST Repository

    Tian, Dong

    2015-07-02

    In order to directly use methane without a reforming process, NiO-Sm0.2Ce0.8O1.9 (NiO-SDC) nanocomposite anode are successfully synthesized via a one-pot, surfactant-assisted co-assembly approach for direct-methane solid oxide fuel cells. Both NiO with cubic phase and SDC with fluorite phase are obtained at 550 °C. Both NiO nanoparticles and SDC nanoparticles are highly monodispersed in size with nearly spherical shapes. Based on the as-synthesized NiO-SDC, two kinds of single cells with different micro/macro-porous structure are successfully fabricated. As a result, the cell performance was improved by 40%-45% with the new double-pore NiO-SDC anode relative to the cell performance with the conventional NiO-SDC anode due to a wider triple-phase-boundary (TPB) area. In addition, no significant degradation of the cell performance was observed after 60 hours, which means an increasing of long term stability. Therefore, the as-synthesized NiO-SDC nanocomposite is a promising anode for direct-methane solid oxide fuel cells.

  14. Evaluation Of Landfill Gas Decay Constant For Municipal Solid Waste Landfills Operated As Bioreactors

    Science.gov (United States)

    Prediction of the rate of gas production from bioreactor landfills is important to optimize energy recovery and to estimate greenhouse gas emissions. Landfill gas (LFG) composition and flow rate were monitored for four years for a conventional and two bioreactor landfill landfil...

  15. Evaluation of potential opportunities for electric power generation from landfill gas at “Tsalapitsa”

    Directory of Open Access Journals (Sweden)

    Ganev Ivaylo

    2014-01-01

    Full Text Available Potential opportunities for electric power generation from landfill gas (LFG utilization were estimated for the second largest landfill site in Bulgaria, situated near the city of Plovdiv. The work performed was based on detailed analysis of experimentally obtained and model-predicted features of the “Tsalapitsa” landfill site. The study presents a short description of the site, the global characteristics of the disposed municipal solid waste, and the experimentally obtained methane composition of the LFG. Based on the above described observations, the potential for LFG recovery at “Tsalapitsa” was determined, together with that for electric power generation for the next 25 years. A set of recommendations was then developed regarding the parameters required for the installation of electric power generation from LFG in Plovdiv.

  16. Microbial Community Structure and Function at an Aquifer Contaminated with Landfill Leachate (Norman,OK)

    Science.gov (United States)

    Weiss, J. V.; Voytek, M. A.; Lowit, M. B.; Cozzarelli, I. M.; Kirshtein, J. D.

    2006-05-01

    Geochemical research at an aquifer contaminated with landfill leachate (Norman, OK) has shown that contaminated areas have significant increases in the concentration of dissolved organic carbon (DOC) and persistent anaerobic conditions as compared to uncontaminated areas. As a result, sulfate is depleted in the center of the contaminant plume with concomitant increases in Fe(II) and methane. These observations have been used to infer the dominant biogeochemical processes in this ecosystem which include Fe reduction, sulfate reduction, and methanogenesis. Because each of these processes is microbially-mediated, the goal of this study was to use a combination of culture-based and molecular methods to determine the composition and diversity of the microbial community in the contaminant plume. Groundwater and sediment samples were collected along the flow path of contamination in June 2005. We used most probable number (MPN) analyses to determine the abundances of key functional groups of bacteria including methanogens, sulfate-reducers (SRB), and iron-reducers (FeRB). Quantitative PCR (qPCR) was performed to determine abundances of functional genes of the dissimilatory sulfite reductase (dsr) and methyl coenzyme M-reductase (mcr) genes and the 16 rRNA genes targeting Geobacter spp. Results from the MPN analyses confirmed the presence of a relatively abundant and diverse anaerobic community in the groundwater at the landfill (e.g. 102 SRB, FeRB ml-1. In general, with increasing distance from the source of contamination, abundances of FeRB, SRB, and methanogens decreased to < 101 cells ml-1 groundwater and < 102 cells g soil. In fact, most of these groups were undetectable throughout much of the sampling transect, particularly in the groundwater. For example, methanogens were largely absent despite the presence of high concentrations of methane. In contrast to these estimates obtained with MPN analyses, the results of qPCR indicated that there were measurable, and many

  17. A review of landfill microbiology research

    Energy Technology Data Exchange (ETDEWEB)

    Archer, D.; Reynolds, P.; Blakey, N.C.

    1995-05-01

    In May 1994 the DTI through ETSU commissioned WRc to undertake a comprehensive review of the landfill microbiology programme to date. The review has attempted to identify remaining gaps in knowledge which are most likely to find application in controlling the production of gas from landfills, and concludes with a list of recommendations for specific landfill process research which is likely to facilitate and optimise energy recovery from landfill. (UK)

  18. LANDFILL BIOREACTOR PERFORMANCE, SECOND INTERIM REPORT

    Science.gov (United States)

    A bioreactor landfill is a landfill that is operated in a manner that is expected to increase the rate and extent of waste decomposition, gas generation, and settlement compared to a traditional landfill. This Second Interim Report was prepared to provide an interpretation of fie...

  19. Quantitative Study of Biogas Generation Potential from Different Landfill Sites of Nepal

    Directory of Open Access Journals (Sweden)

    Bikash Adhikari

    2015-01-01

    Full Text Available This research paper was study of waste composition and quantitative analysis of biogas generation potential with its recovery at Sisdole, Pokhara and Karaute Dada landfill sites (LFS of Nepal. The waste management practice in LFS are significant deciding factors for the assessment of environmental impacts caused including the release of green house gases like methane, carbondioxide etc to the atmosphere, that could contribute significantly to global warming and climate change. The total waste disposed to Sisdole LFS, Pokhara LFS and Karaute Dada LFS are 410, 80 and 7.8 tons respectively.  The waste composition was studied onsite with waste reduction method and analyzed for their composition. The organic component of wastes was found high as 61.6%, 52.5% and 65% at Sisdole, Pokhara and Karaute Dada LFS respectively. The biogas potential at these landfill sites were 12157.78 cum, 851.99 cum and 169 cum of biogas per day in Sisdole, Pokhara and Karaute Dada LFS respectively. 4.68, 0.33 and 0.07 MW energy per day can be generated from these amounts of biogas produced in Sisdole, Pokhara and Karaute Dada LFS respectively. Proper gas collection system can be the source of income from these landfill sites and help to mitigate the adverse impact of methane that is being released from these landfill sites

  20. Sustainable treatment of landfill leachate

    Science.gov (United States)

    Kamaruddin, Mohamad Anuar; Yusoff, Mohd. Suffian; Aziz, Hamidi Abdul; Hung, Yung-Tse

    2015-06-01

    Landfill leachate is a complex liquid that contains excessive concentrations of biodegradable and non-biodegradable products including organic matter, phenols, ammonia nitrogen, phosphate, heavy metals, and sulfide. If not properly treated and safely disposed, landfill leachate could be an impending source to surface and ground water contamination as it may percolate throughout soils and subsoils, causing adverse impacts to receiving waters. Lately, various types of treatment methods have been proposed to alleviate the risks of untreated leachate. However, some of the available techniques remain complicated, expensive and generally require definite adaptation during process. In this article, a review of literature reported from 2008 to 2012 on sustainable landfill leachate treatment technologies is discussed which includes biological and physical-chemical techniques, respectively.

  1. Use of Impervious Covers and Carbon Adsorption for the Control of Leachate Production in Municipal Landfills.

    Science.gov (United States)

    1979-05-01

    studies are explained in part by the following factors: age of the landfill and corresponding state of stabilization ; composition of the solid waste, the...polyethylene (PE), polyvinyl chloride (PVC), butyl rubber, Hyalon (a registered trademark of Dupont), ethylene propylene diene monomer ( EPDM ), chlorinated...an active anaerobic population of methane formers. The removal of organics resulted in a more rapid stabilization or "aging" of the experimental

  2. Effects of trace volatile organic compounds on methane oxidation

    Directory of Open Access Journals (Sweden)

    Wilai Chiemchaisri

    2001-06-01

    Full Text Available The effects of volatile organic compounds (VOCs on methane oxidation in landfill cover soils were examined. The batch experiments were conducted using single and mixed VOCs, such as, dichloromethane (DCM, trichloroethylene (TCE, tetrachloroethylene (PCE, and benzene. The results from all combinations showed a decrease in methane oxidation rate with increase in VOC concentrations. Moreover, inhibition effects of TCE and DCM were found higher than benzene and PCE. The reduction of methane oxidation by benzene and PCE could be attributed to the toxicity effect, whereas TCE and DCM were found to exhibit the competitive-inhibition effect. When the soil was mixed with DCM, no methane oxidation was found. Damage to the cell’s internal membrane was found in a methanotrophic culture exposed to VOC gases which is the attachment site of a key enzyme needed for methane oxidationOs efeitos dos compostos orgânicos voláteis (VOCs na oxidação do metano em camadas superficiais do solo. Os experimentos foram conduzidos usando somente VOCs ou mistura do mesmo, como, diclorometano (DCM, tricloroetileno (TCE, tetracloroetileno (PCE, e benzeno. Os resultados de todas as combinações mostraram uma diminuição na taxa da oxidação do metano com aumento nas concentrações de VOC. Além disso, os efeitos da inibição de TCE e de DCM foram mais elevados do que do benzeno e PCE. A redução da oxidação do metano pelo benzeno e PCE poderia ser atribuída ao efeito da toxicidade, visto que TCE e DCM exibiram o efeito de competição-inibição. Quando o solo foi misturado com o DCM, nenhuma oxidação do metano foi encontrada. Os danos à membrana interna celular foi observada em uma cultura metanotrófica exposta aos gases de VOC que é o local de ligação de uma enzima chave necessário para a oxidação do metano.

  3. Effects of exogenous aerobic bacteria on methane production and biodegradation of municipal solid waste in bioreactors.

    Science.gov (United States)

    Ge, Sai; Liu, Lei; Xue, Qiang; Yuan, Zhiming

    2016-09-01

    Landfill is the most common and efficient ways of municipal solid waste (MSW) disposal and the landfill biogas, mostly methane, is currently utilized to generate electricity and heat. The aim of this work is to study the effects and the role of exogenous aerobic bacteria mixture (EABM) on methane production and biodegradation of MSW in bioreactors. The results showed that the addition of EABM could effectively enhance hydrolysis and acidogenesis processes of MSW degradation, resulting in 63.95% reduction of volatile solid (VS), the highest methane production rate (89.83Lkg(-1) organic matter) ever recorded and a threefold increase in accumulative methane production (362.9L) than the control (127.1L). In addition, it is demonstrated that white-rot fungi (WRF) might further promote the methane production through highly decomposing lignin, but the lower pH value in leachate and longer acidogenesis duration may cause methane production reduced. The data demonstrated that methane production and biodegradation of MSW in bioreactors could be significantly enhanced by EABM via enhanced hydrolysis and acidogenesis processes, and the results are of great economic importance for the future design and management of landfill.

  4. 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

  5. Emission model for landfills with mechanically-biologically pretreated waste, with the emphasis on modelling the gas balance; Emissionsprognosemodell fuer Deponien mit mechanisch-biologisch vorbehandelten Abfaellen - Schwerpunkt: Modellierung des Gashaushaltes

    Energy Technology Data Exchange (ETDEWEB)

    Danhamer, H.

    2001-07-01

    The objective of this work was to determine influence factors on processes going on in landfills with mechanically-biologically pretreated waste (MBP-landfills) in order to predict emissions. For this purpose a computer based model has been developed. The model allows to simulate the gas, water and heat balance as well as settlement processes and was called DESIM2005 (version MB). It is based on theoretical modeling approaches as well as data from lab and reactor experiments. The main focus of model application was to determine factors influencing the gas phase and the emissions of landfill gas and methane during operation and aftercare of MBP-landfills. By performing simulations the effects of changing parameters for the processes gas transport and biological degradation as well as the effects of different qualities in waste pretreatment and of varying landfill operation techniques were investigated. Possibilities for increasing the environmental sustainability of landfills containing mechanically-biologically pretreated waste were shown. (orig.)

  6. Impact assessment of intermediate soil cover on landfill stabilization by characterizing landfilled municipal solid waste.

    Science.gov (United States)

    Qi, Guangxia; Yue, Dongbei; Liu, Jianguo; Li, Rui; Shi, Xiaochong; He, Liang; Guo, Jingting; Miao, Haomei; Nie, Yongfeng

    2013-10-15

    Waste samples at different depths of a covered municipal solid waste (MSW) landfill in Beijing, China, were excavated and characterized to investigate the impact of intermediate soil cover on waste stabilization. A comparatively high amount of unstable organic matter with 83.3 g kg(-1) dry weight (dw) total organic carbon was detected in the 6-year-old MSW, where toxic inorganic elements containing As, Cd, Cr, Cu, Mn, Ni, Pb, and Zn of 10.1, 0.98, 85.49, 259.7, 530.4, 30.5, 84.0, and 981.7 mg kg(-1) dw, respectively, largely accumulated because of the barrier effect of intermediate soil cover. This accumulation resulted in decreased microbial activities. The intermediate soil cover also caused significant reduction in moisture in MSW under the soil layer, which was as low as 25.9%, and led to inefficient biodegradation of 8- and 10-year-old MSW. Therefore, intermediate soil cover with low permeability seems to act as a barrier that divides a landfill into two landfill cells with different degradation processes by restraining water flow and hazardous matter.

  7. Enhanced methane production in an anaerobic digestion and microbial electrolysis cell coupled system with co-cultivation of Geobacter and Methanosarcina.

    Science.gov (United States)

    Yin, Qi; Zhu, Xiaoyu; Zhan, Guoqiang; Bo, Tao; Yang, Yanfei; Tao, Yong; He, Xiaohong; Li, Daping; Yan, Zhiying

    2016-04-01

    The anaerobic digestion (AD) and microbial electrolysis cell (MEC) coupled system has been proved to be a promising process for biomethane production. In this paper, it was found that by co-cultivating Geobacter with Methanosarcina in an AD-MEC coupled system, methane yield was further increased by 24.1%, achieving to 360.2 mL/g-COD, which was comparable to the theoretical methane yield of an anaerobic digester. With the presence of Geobacter, the maximum chemical oxygen demand (COD) removal rate (216.8 mg COD/(L·hr)) and current density (304.3A/m(3)) were both increased by 1.3 and 1.8 fold compared to the previous study without Geobacter, resulting in overall energy efficiency reaching up to 74.6%. Community analysis demonstrated that Geobacter and Methanosarcina could coexist together in the biofilm, and the electrochemical activities of both were confirmed by cyclic voltammetry. Our study observed that the carbon dioxide content in total gas generated from the AD reactor with Geobacter was only half of that generated from the same reactor without Geobacter, suggesting that Methanosarcina may obtain the electron transferred from Geobacter for the reduction of carbon dioxide to methane. Taken together, Geobacter not only can improve the performance of the MEC system, but also can enhance methane production.

  8. Decomposition and carbon storage of selected paper products in laboratory-scale landfills

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaoming, E-mail: wangxiaoming_cqu@163.com [Key Laboratory of Three Gorges Reservoir Region' s Eco-Environment, Ministry of Education, National Center for International Research of Low-Carbon and Green Buildings, Chongqing University, Chongqing (China); Department of Civil, Construction, and Environmental Engineering, Campus Box 7908, North Carolina State University, Raleigh, NC 27695-7908 (United States); De la Cruz, Florentino B. [Department of Civil, Construction, and Environmental Engineering, Campus Box 7908, North Carolina State University, Raleigh, NC 27695-7908 (United States); Ximenes, Fabiano [Department of Primary Industries, New South Wales (Australia); Barlaz, Morton A. [Department of Civil, Construction, and Environmental Engineering, Campus Box 7908, North Carolina State University, Raleigh, NC 27695-7908 (United States)

    2015-11-01

    The objective of this study was to measure the anaerobic biodegradation of different types of paper products in laboratory-scale landfill reactors. The study included (a) measurement of the loss of cellulose, hemicellulose, organic carbon, and (b) measurement of the methane yields for each paper product. The test materials included two samples each of newsprint (NP), copy paper (CP), and magazine paper (MG), and one sample of diaper (DP). The methane yields, carbon storage factors and the extent of cellulose and hemicellulose decomposition all consistently show that papers made from mechanical pulps (e.g., NPs) are less degradable than those made from chemical pulps where essentially all lignin was chemically removed (e.g., CPs). The diaper, which is not only made from chemical pulp but also contains some gel and plastic, exhibited limited biodegradability. The extent of biogenic carbon conversion varied from 21 to 96% among papers, which contrasts with the uniform assumption of 50% by the Intergovernmental Panel on Climate Change (IPCC) for all degradable materials discarded in landfills. Biochemical methane potential tests also showed that the solids to liquid ratio used in the test can influence the results. - Highlights: • Decomposition of major paper products measured under simulated landfill conditions • Varied decomposition behaviors across paper types governed by pulp types • A copy paper made from eucalyptus exhibited inhibited decomposition.

  9. Stable isotope signatures for characterising the biological stability of landfilled municipal solid waste

    Energy Technology Data Exchange (ETDEWEB)

    Wimmer, Bernhard, E-mail: bernhard.wimmer@ait.ac.at [AIT Austrian Institute of Technology GmbH, Health and Environment Department, Environmental Resources and Technologies, Konrad-Lorenz-Strasse 24, 3430 Tulln (Austria); Hrad, Marlies; Huber-Humer, Marion [Institute of Waste Management, Department of Water-Atmosphere-Environment, University of Natural Resources and Life Sciences, Muthgasse 107, 1190 Vienna (Austria); Watzinger, Andrea; Wyhlidal, Stefan; Reichenauer, Thomas G. [AIT Austrian Institute of Technology GmbH, Health and Environment Department, Environmental Resources and Technologies, Konrad-Lorenz-Strasse 24, 3430 Tulln (Austria)

    2013-10-15

    Highlights: ► The isotopic signature of δ{sup 13}C-DIC of leachates is linked to the reactivity of MSW. ► Isotopic signatures of leachates depend on aerobic/anaerobic conditions in landfills. ► In situ aeration of landfills can be monitored by isotope analysis in leachate. ► The isotopic analysis of leachates can be used for assessing the stability of MSW. ► δ{sup 13}C-DIC of leachates helps to define the duration of landfill aftercare. - Abstract: Stable isotopic signatures of landfill leachates are influenced by processes within municipal solid waste (MSW) landfills mainly depending on the aerobic/anaerobic phase of the landfill. We investigated the isotopic signatures of δ{sup 13}C, δ{sup 2}H and δ{sup 18}O of different leachates from lab-scale experiments, lysimeter experiments and a landfill under in situ aeration. In the laboratory, columns filled with MSW of different age and reactivity were percolated under aerobic and anaerobic conditions. In landfill simulation reactors, waste of a 25 year old landfill was kept under aerobic and anaerobic conditions. The lysimeter facility was filled with mechanically shredded fresh waste. After starting of the methane production the waste in the lysimeter containments was aerated in situ. Leachate and gas composition were monitored continuously. In addition the seepage water of an old landfill was collected and analysed periodically before and during an in situ aeration. We found significant differences in the δ{sup 13}C-value of the dissolved inorganic carbon (δ{sup 13}C-DIC) of the leachate between aerobic and anaerobic waste material. During aerobic degradation, the signature of δ{sup 13}C-DIC was mainly dependent on the isotopic composition of the organic matter in the waste, resulting in a δ{sup 13}C-DIC of −20‰ to −25‰. The production of methane under anaerobic conditions caused an increase in δ{sup 13}C-DIC up to values of +10‰ and higher depending on the actual reactivity of the MSW

  10. Minimizing N2O fluxes from full-scale municipal solid waste landfill with properly selected cover soil

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Municipal solid waste landfills emit nitrous oxide (N2O) gas. Assuming that the soil cover is the primary N2O source from landfills,this study tested, during a four-year project, the hypothesis that the proper use of chosen soils with fine texture minimizes N2O emissions. A full-scale sanitary landfill, a full-scale bioreactor landfill and a cell planted with Nerium indicum or Festuca arundinacea Schreb, at the Hangzhou Tianziling landfill in Hangzhou City were the test sites. The N2O emission rates from all test sites were considerably lower than those reported in the published reports. Specifically, the N2O emission rate was dependent on soil water content and nitrate concentrations in the cover soil. The effects of leachate recirculation and irrigation were minimal. Properly chosen cover soils applied to the landfills reduced N2O flux.

  11. Recovery Act: Brea California Combined Cycle Electric Generating Plant Fueled by Waste Landfill Gas

    Energy Technology Data Exchange (ETDEWEB)

    Galowitz, Stephen

    2012-12-31

    The primary objective of the Project was to maximize the productive use of the substantial quantities of waste landfill gas generated and collected at the Olinda Landfill near Brea, California. An extensive analysis was conducted and it was determined that utilization of the waste gas for power generation in a combustion turbine combined cycle facility was the highest and best use. The resulting Project reflected a cost effective balance of the following specific sub-objectives: • Meeting the environmental and regulatory requirements, particularly the compliance obligations imposed on the landfill to collect, process and destroy landfill gas • Utilizing proven and reliable technology and equipment • Maximizing electrical efficiency • Maximizing electric generating capacity, consistent with the anticipated quantities of landfill gas generated and collected at the Olinda Landfill • Maximizing equipment uptime • Minimizing water consumption • Minimizing post-combustion emissions • The Project produced and will produce a myriad of beneficial impacts. o The Project created 360 FTE construction and manufacturing jobs and 15 FTE permanent jobs associated with the operation and maintenance of the plant and equipment. o By combining state-of-the-art gas clean up systems with post combustion emissions control systems, the Project established new national standards for best available control technology (BACT). o The Project will annually produce 280,320 MWh’s of clean energy o By destroying the methane in the landfill gas, the Project will generate CO2 equivalent reductions of 164,938 tons annually. The completed facility produces 27.4 MWnet and operates 24 hours a day, seven days a week.

  12. A correction in the CDM methodological tool for estimating methane emissions from solid waste disposal sites.

    Science.gov (United States)

    Santos, M M O; van Elk, A G P; Romanel, C

    2015-12-01

    Solid waste disposal sites (SWDS) - especially landfills - are a significant source of methane, a greenhouse gas. Although having the potential to be captured and used as a fuel, most of the methane formed in SWDS is emitted to the atmosphere, mainly in developing countries. Methane emissions have to be estimated in national inventories. To help this task the Intergovernmental Panel on Climate Change (IPCC) has published three sets of guidelines. In addition, the Kyoto Protocol established the Clean Development Mechanism (CDM) to assist the developed countries to offset their own greenhouse gas emissions by assisting other countries to achieve sustainable development while reducing emissions. Based on methodologies provided by the IPCC regarding SWDS, the CDM Executive Board has issued a tool to be used by project developers for estimating baseline methane emissions in their project activities - on burning biogas from landfills or on preventing biomass to be landfilled and so avoiding methane emissions. Some inconsistencies in the first two IPCC guidelines have already been pointed out in an Annex of IPCC latest edition, although with hidden details. The CDM tool uses a model for methane estimation that takes on board parameters, factors and assumptions provided in the latest IPCC guidelines, while using in its core equation the one of the second IPCC edition with its shortcoming as well as allowing a misunderstanding of the time variable. Consequences of wrong ex-ante estimation of baseline emissions regarding CDM project activities can be of economical or environmental type. Example of the first type is the overestimation of 18% in an actual project on biogas from landfill in Brazil that harms its developers; of the second type, the overestimation of 35% in a project preventing municipal solid waste from being landfilled in China, which harms the environment, not for the project per se but for the undue generated carbon credits. In a simulated landfill - the same

  13. Landfilling of waste incineration residues

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Astrup, Thomas; Cai, Zuansi

    2002-01-01

    Residues from waste incineration are bottom ashes and air-pollution-control (APC) residues including fly ashes. The leaching of heavy metals and salts from the ashes is substantial and a wide spectrum of leaching tests and corresponding criteria have been introduced to regulate the landfilling...

  14. Methane Emissions from Permafrost Regions using Low-Power Eddy Covariance Stations

    Science.gov (United States)

    Burba, G.; Sturtevant, C.; Schreiber, P.; Peltola, O.; Zulueta, R.; Mammarella, I.; Haapanala, S.; Rinne, J.; Vesala, T.; McDermitt, D.; Oechel, W.

    2012-04-01

    Methane is an important greenhouse gas with a warming potential 23 times that of carbon dioxide over a 100-year cycle. The permafrost regions of the world store significant amounts of organic materials under anaerobic conditions, leading to large methane production and accumulation in the upper layers of bedrock, soil and ice. These regions are currently undergoing dramatic change in response to warming trends, and may become a significant potential source of global methane release under a warming climate over the coming decades and centuries. Presently, most measurements of methane fluxes in permafrost regions have been made with static chamber techniques, and very few were done with the eddy covariance approach using closed-path analyzers. Although chambers and closed-path analyzers have advantages, both techniques have significant limitations, especially for permafrost research. Static chamber measurements are discrete in time and space, and particularly difficult to use over polygonal tundra with highly non-uniform micro-topography and active water layer. They also may not capture the dynamics of methane fluxes on varying time scales (hours to annual estimates). In addition, placement of the chamber may disturb the surface integrity causing a significant over-estimation of the measured flux. Closed-path gas analyzers for measuring methane eddy fluxes employ advanced technologies such as TDLS (Tunable Diode Laser Spectroscopy), ICOS (Integrated Cavity Output Spectroscopy), WS-CRDS (wavelength scanned cavity ring-down spectroscopy), but require high flow rates at significantly reduced optical cell pressures to provide adequate response time and sharpen absorption features. Such methods, when used with the eddy covariance technique, require a vacuum pump and a total of 400-1500 Watts of grid power for the pump and analyzer system. The weight of such systems often exceeds 100-200 lbs, restricting practical applicability for remote or portable field studies. As a

  15. Determination of the boundary of carbon formation for dry reforming of methane in a solid oxide fuel cell

    Science.gov (United States)

    Assabumrungrat, S.; Laosiripojana, N.; Piroonlerkgul, P.

    The boundary of carbon formation for the dry reforming of methane in direct internal reforming solid oxide fuel cells (DIR-SOFCs) with different types of electrolyte (i.e., an oxygen ion-conducting electrolyte (SOFC-O 2-) and a proton-conducting electrolyte (SOFC-H +)) was determined by employing detailed thermodynamic analysis. It was found that the required CO 2/CH 4 ratio decreased with increasing temperature. The type of electrolyte influenced the boundary of carbon formation because it determined the location of water formed by the electrochemical reaction. The extent of the electrochemical reaction also played an important role in the boundary of carbon formation. For SOFC-O 2-, the required CO 2/CH 4 ratio decreased with the increasing extent of the electrochemical reaction due to the presence of electrochemical water in the anode chamber. Although for SOFC-H + the required CO 2/CH 4 ratio increased with the increasing extent of the electrochemical reaction at high operating temperature (T > 1000 K) following the trend previously reported for the case of steam reforming of methane with addition of water as a carbon suppresser, an unusual opposite trend was observed at lower operating temperature. The study also considered the use of water or air as an alternative carbon suppresser for the system. The required H 2O/CH 4 ratio and air/CH 4 ratio were determined for various inlet CO 2/CH 4 ratios. Even air is a less attractive choice compared to water due to the higher required air/CH 4 ratio than the H 2O/CH 4 ratio; however, the integration of exothermic oxidation and the endothermic reforming reactions may make the use of air attractive. Water was found to be more effective than carbon dioxide in suppressing the carbon formation at low temperatures but their effect was comparable at high temperatures. Although the results from the study were based on calculations of the SOFCs with different electrolytes, they are also useful for selecting suitable feed

  16. Differences in volatile methyl siloxane (VMS) profiles in biogas from landfills and anaerobic digesters and energetics of VMS transformations.

    Science.gov (United States)

    Tansel, Berrin; Surita, Sharon C

    2014-11-01

    The objectives of this study were to compare the types and levels of volatile methyl siloxanes (VMS) present in biogas generated in the anaerobic digesters and landfills, evaluate the energetics of siloxane transformations under anaerobic conditions, compare the conditions in anaerobic digesters and municipal solid waste (MSW) landfills which result in differences in siloxane compositions. Biogas samples were collected at the South District Wastewater Treatment Plant and South Dade Landfill in Miami, Florida. In the digester gas, D4 and D5 comprised the bulk of total siloxanes (62% and 27%, respectively) whereas in the landfill gas, the bulk of siloxanes were trimethylsilanol (TMSOH) (58%) followed by D4 (17%). Presence of high levels of TMSOH in the landfill gas indicates that methane utilization may be a possible reaction mechanism for TMSOH formation. The free energy change for transformation of D5 and D4 to TMSOH either by hydrogen or methane utilization are thermodynamically favorable. Either hydrogen or methane should be present at relatively high concentrations for TMSOH formation which explains the high levels present in the landfill gas. The high bond energy and bond distance of the Si-O bond, in view of the atomic sizes of Si and O atoms, indicate that Si atoms can provide a barrier, making it difficult to break the Si-O bonds especially for molecules with specific geometric configurations such as D4 and D5 where oxygen atoms are positioned inside the frame formed by the large Si atoms which are surrounded by the methyl groups.

  17. Quantifying Methane Fluxes Simply and Accurately: The Tracer Dilution Method

    Science.gov (United States)

    Rella, Christopher; Crosson, Eric; Green, Roger; Hater, Gary; Dayton, Dave; Lafleur, Rick; Merrill, Ray; Tan, Sze; Thoma, Eben

    2010-05-01

    Methane is an important atmospheric constituent with a wide variety of sources, both natural and anthropogenic, including wetlands and other water bodies, permafrost, farms, landfills, and areas with significant petrochemical exploration, drilling, transport, or processing, or refining occurs. Despite its importance to the carbon cycle, its significant impact as a greenhouse gas, and its ubiquity in modern life as a source of energy, its sources and sinks in marine and terrestrial ecosystems are only poorly understood. This is largely because high quality, quantitative measurements of methane fluxes in these different environments have not been available, due both to the lack of robust field-deployable instrumentation as well as to the fact that most significant sources of methane extend over large areas (from 10's to 1,000,000's of square meters) and are heterogeneous emitters - i.e., the methane is not emitted evenly over the area in question. Quantifying the total methane emissions from such sources becomes a tremendous challenge, compounded by the fact that atmospheric transport from emission point to detection point can be highly variable. In this presentation we describe a robust, accurate, and easy-to-deploy technique called the tracer dilution method, in which a known gas (such as acetylene, nitrous oxide, or sulfur hexafluoride) is released in the same vicinity of the methane emissions. Measurements of methane and the tracer gas are then made downwind of the release point, in the so-called far-field, where the area of methane emissions cannot be distinguished from a point source (i.e., the two gas plumes are well-mixed). In this regime, the methane emissions are given by the ratio of the two measured concentrations, multiplied by the known tracer emission rate. The challenges associated with atmospheric variability and heterogeneous methane emissions are handled automatically by the transport and dispersion of the tracer. We present detailed methane flux

  18. Preface for the Special Column of Methane Transformation

    Institute of Scientific and Technical Information of China (English)

    Ye Wang

    2009-01-01

    @@ Methane is the main constituent of natural gas, coal-bed gas, landfill gas and methane hydrate resources. These resources may be used more efficiently as clean fuels or as chemical feedstocks if methane can be effectively transformed into liquid fuels or chemicals. However, methane only possesses C-H bonds and is a very stable organic molecule hard to functionalize. The C-H activation, particularly the selective functionalization of C-H bonds in saturated hydrocarbons, remains a difficult challenge in chemistry. The present technology for chemical utilization of methane involves the steam reforming of methane to synthesis gas and the subsequent transformation of synthesis gas to methanol or hydrocarbon fuels via methanol synthesis or Fischer-Tropsch synthesis. However, the steam reforming of methane is a high-cost process. The development of more efficient and economical processes for methane transformation is a dream of all chemists and chemical engineers. I think that this is also one of the most important themes of the Journal of Natural Gas Chemistry.

  19. Auto generation plant of Artigas landfill (Bilbao, Spain); Planta de autogeneracion electrica del vertedero de Artigas (Bilbao)

    Energy Technology Data Exchange (ETDEWEB)

    Carreras, N.; Dorronsoro, J.L.

    1996-07-01

    The disposition of MSW in the landfill generates a mixture of gases or {sup b}iogas{sup ,} its primary content is methane (50-60%) which has a very important energetic value, that can be very useful. In this sense, the present work point out the characteristics of the auto generation electrical plant of Artigas landfill, just like the results of the analytical study of the past two years. In this project which was partly funded by the UE, have participated Excmo. Ayuntamiento de Bilbao, EVE and CIEMAT. (Author) 6 refs.

  20. Imaging and characterization of heterogeneous landfills using geophysical methods

    NARCIS (Netherlands)

    Konstantaki, L.A.

    2016-01-01

    Nowadays many countries use landfilling for the management of their waste or for treating old landfills. Emissions from landfills can be harmful to the environment and to human health, making the stabilization of landfills a priority for the landfill communities. Estimation of the emission potential

  1. Plume mapping and isotopic characterisation of anthropogenic methane sources

    Science.gov (United States)

    Zazzeri, G.; Lowry, D.; Fisher, R. E.; France, J. L.; Lanoisellé, M.; Nisbet, E. G.

    2015-06-01

    Methane stable isotope analysis, coupled with mole fraction measurement, has been used to link isotopic signature to methane emissions from landfill sites, coal mines and gas leaks in the United Kingdom. A mobile Picarro G2301 CRDS (Cavity Ring-Down Spectroscopy) analyser was installed on a vehicle, together with an anemometer and GPS receiver, to measure atmospheric methane mole fractions and their relative location while driving at speeds up to 80 kph. In targeted areas, when the methane plume was intercepted, air samples were collected in Tedlar bags, for δ13C-CH4 isotopic analysis by CF-GC-IRMS (Continuous Flow Gas Chromatography-Isotope Ratio Mass Spectrometry). This method provides high precision isotopic values, determining δ13C-CH4 to ±0.05 per mil. The bulk signature of the methane plume into the atmosphere from the whole source area was obtained by Keeling plot analysis, and a δ13C-CH4 signature, with the relative uncertainty, allocated to each methane source investigated. Both landfill and natural gas emissions in SE England have tightly constrained isotopic signatures. The averaged δ13C-CH4 for landfill sites is -58 ± 3‰. The δ13C-CH4 signature for gas leaks is also fairly constant around -36 ± 2‰, a value characteristic of homogenised North Sea supply. In contrast, signatures for coal mines in N. England and Wales fall in a range of -51.2 ± 0.3‰ to -30.9 ± 1.4‰, but can be tightly constrained by region. The study demonstrates that CRDS-based mobile methane measurement coupled with off-line high precision isotopic analysis of plume samples is an efficient way of characterising methane sources. It shows that isotopic measurements allow type identification, and possible location of previously unknown methane sources. In modelling studies this measurement provides an independent constraint to determine the contributions of different sources to the regional methane budget and in the verification of inventory source distribution.

  2. Ni modified ceramic anodes for direct-methane solid oxide fuel cells

    Science.gov (United States)

    Xiao, Guoliang; Chen, Fanglin

    2016-01-19

    In accordance with certain embodiments of the present disclosure, a method for fabricating a solid oxide fuel cell is described. The method includes synthesizing a composition having a perovskite present therein. The method further includes applying the composition on an electrolyte support to form an anode and applying Ni to the composition on the anode.

  3. Identification of Cellulose Breaking Bacteria in Landfill Samples for Organic Waste Management

    Science.gov (United States)

    Chan, P. M.; Leung, F. C.

    2015-12-01

    According to the Hong Kong Environmental Protection Department, the citizens of Hong Kong disposes 13,500 tonnes of waste to the landfill everyday. Out of the 13,500 tonnes, 3600 tonnes consist of organic waste. Furthermore, due to the limited supply of land for landfills in Hong Kong, it is estimated that landfills will be full by about 2020. Currently, organic wastes at landfills undergo anaerobic respiration, where methane gas, one of the most harmful green house gases, will be released. The management of such waste is a pressing issue, as possible solutions must be presented in this crucial period of time. The Independent Schools Foundation Academy introduced their very own method to manage the waste produced by the students. With an approximate of 1500 students on campus, the school produces 27 metric tonnes of food waste each academic year. The installation of the rocket food composter provides an alternate method of disposable of organic waste the school produces, for the aerobic environment allows for different by-products to be produced, namely compost that can be used for organic farming by the primary school students and subsequently carbon dioxide, a less harmful greenhouse gas. This research is an extension on the current work, as another natural factor is considered. It evaluates the microorganism community present in leachate samples collected from the North East New Territories Landfill, for the bacteria in the area exhibits special characteristics in the process of decomposition. Through the sequencing and analysis of the genome of the bacteria, the identification of the bacteria might lead to a break through on the current issue. Some bacteria demonstrate the ability to degrade lignin cellulose, or assist in the production of methane gas in aerobic respirations. These characteristics can hopefully be utilized in the future in waste managements across the globe.

  4. Emerging contaminants at a closed and an operating landfill in Oklahoma

    Science.gov (United States)

    Andrews, William J.; Masoner, Jason R.; Cozzarelli, Isabelle M.

    2012-01-01

    Landfills are the final depositories for a wide range of solid waste from both residential and commercial sources, and therefore have the potential to produce leachate containing many organic compounds found in consumer products such as pharmaceuticals, plasticizers, disinfectants, cleaning agents, fire retardants, flavorings, and preservatives, known as emerging contaminants (ECs). Landfill leachate was sampled from landfill cells of three different age ranges from two landfills in Central Oklahoma. Samples were collected from an old cell containing solid waste greater than 25 years old, an intermediate age cell with solid waste between 16 and 3 years old, and operating cell with solid waste less than 5 years old to investigate the chemical variability and persistence of selected ECs in landfill leachate of differing age sources. Twenty-eight of 69 analyzed ECs were detected in one or more samples from the three leachate sources. Detected ECs ranged in concentration from 0.11 to 114 μg/L and included 4 fecal and plant sterols, 13 household\\industrial, 7 hydrocarbon, and 4 pesticide compounds. Four ECs were solely detected in the oldest leachate sample, two ECs were solely detected in the intermediate leachate sample, and no ECs were solely detected in the youngest leachate sample. Eleven ECs were commonly detected in all three leachate samples and are an indication of the contents of solid waste deposited over several decades and the relative resistance of some ECs to natural attenuation processes in and near landfills.

  5. LANDFILL LEACHATES PRETREATMENT BY OZONATION

    Directory of Open Access Journals (Sweden)

    Jacek Leszczyński

    2016-06-01

    Full Text Available In this paper, the application of ozonation processes for stabilized landfill leachate treatment was investigated. The leachate came from a municipal sanitary landfill located nearby Bielsk Podlaski. The average values of its main parameters were: pH 8.23; COD 870 mgO2/dm3; BOD 90 mgO2/dm3; NH4+ 136.2 mgN/dm3; UV254 absorbance 0.312 and turbidity 14 NTU. The ozone dosages used were in the range of 115.5 to 808.5 mgO3/dm3 of the leachate. The maximum COD, color and UV254 absorbance removal wa.5 mgO3/dm3. After oxidation, the ratio of BOD/COD was increased from 0.1 up to 0.23.

  6. Methane steam reforming kinetics over Ni-YSZ anode materials for Solid Oxide Fuel Cells

    DEFF Research Database (Denmark)

    Mogensen, David

    energy. The overall efficiency of a fuel cell system operating on natural gas can be significantly improved by having part of the steam reforming take place inside the SOFC stack. In order to avoid large temperature gradients as a result of the highly endothermal steam reforming reaction, the amount...... of internal reforming has to be carefully controlled. The objective of this thesis is to make such a careful control possible by examining the rate of internal steam reforming in SOFCs. The catalytic steam reforming activity of Ni-YSZ anode material was tested both in a packed bed reactor to determine...

  7. Methane steam reforming kinetics over Ni-YSZ anodematerials for Solid Oxide FuelCells

    DEFF Research Database (Denmark)

    Mogensen, David

    energy. The overall efficiency of a fuel cell system operating on natural gas can be significantly improved by having part of the steam reforming take place inside the SOFC stack. In order to avoid large temperature gradients as a result of the highly endothermal steam reforming reaction, the amount...... of internal reforming has to be carefully controlled. The objective of this thesis is to make such a careful control possible by examining the rate of internal steam reforming in SOFCs. The catalytic steam reforming activity of Ni-YSZ anode material was tested both in a packed bed reactor to determine...

  8. Landfill Gas Conversion to LNG and LCO{sub 2}. Phase II Final Report for January 25, 1999 - April 30, 2000

    Energy Technology Data Exchange (ETDEWEB)

    Brown, W. R.; Cook, W. J.; Siwajek, L. A.

    2000-10-20

    This report summarizes work on the development of a process to produce LNG (liquefied methane) for heavy vehicle use from landfill gas (LFG) using Acrion's CO{sub 2} wash process for contaminant removal and CO{sub 2} recovery.

  9. Improved bio-hydrogen production from glucose by adding a specific methane inhibitor to microbial electrolysis cells with a double anode arrangement.

    Science.gov (United States)

    Zhang, Jingnan; Bai, Yanxia; Fan, Yaoting; Hou, Hongwei

    2016-10-01

    Improved hydrogen production from glucose was achieved by adding a specific methane inhibitor (such as chloroform) to repress the activity of methanogens in a single-chamber microbial electrolysis cells (MECs) with a double anode arrangement. A maximum hydrogen production of 8.4±0.2 mol H2/mol-G (G represents glucose), a hydrogen production rate of 2.39±0.3 m(3) H2/m3/d and a high energy efficiency (relative to the electrical input) of ηE=165±5% had been recorded from 1 g/L glucose at a low dosage of chloroform (5‰, v:v) and an applied voltage of 0.8 V. Almost all of the glucose was removed within 4 h, with 66% of the electrons in intermediates (mainly including acetate and ethanol), and methane gas was not detected in the MECs through 11 batch cycles. The experimental results confirmed that chloroform was an effective methane inhibitor that improved hydrogen production from glucose in the MECs. In addition, the cyclic voltammetry tests demonstrated that the electron transfer in the MECs was mainly due to the biofilm-bound redox compounds rather than soluble electron shuttles.

  10. 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.

  11. Gas Transport Parameters for Landfill Final Cover Soil: Measurements and Model Modification by Dry Bulk Density

    Science.gov (United States)

    Wickramarachchi, P. N.; Kawamoto, K.; Hamamoto, S.; Nagamori, M.; Moldrup, P.; Komatsu, T.

    2011-12-01

    Landfill sites have been emerging in greenhouse warming scenarios as a significant source of atmospheric methane (CH4). Until recently, landfill management strategies have mainly addressed the problem of preventing groundwater contamination and reduction of leachate generation. Being one of the largest sources of anthropogenic CH4 emission, the final cover system should also be designed for minimizing the greenhouse gases migration into the atmosphere or the areas surrounding the landfill while securing the hydraulic performance. Compared to the intensive research efforts on hydraulic performances of landfill final cover soil, few studies about gas transport characteristics of landfill cover soils have been done. However, recent soil-gas studies implied that the effects of soil physical properties such as bulk density (i.e., compaction level), soil particle size are key parameters to understand landfill gaseous performance. The gas exchange through the final cover soils is controlled by advective and diffusive gas transport. Air permeability (ka) governs the advective gas transport while the soil-gas diffusion coefficient (Dp) governs diffusive gas transport. In this study, the effects of compaction level and particle size fraction effects on ka and Dp for landfill final cover soil was investigated. The disturbed soil samples were taken from landfill final cover in Japan. A compaction tests were performed for the soil samples with two different size fractions (content , the soil samples were repacked into soil cores (i.d. 15-cm, length 12-cm, 2120 cm3) at two different compaction levels [(MP):2700 kN/m2 and (SP):600 kN/m2]. After the compaction tests, ka and Dp were measured and then samples were saturated and subsequently drained at different soil-water matric potential of 0.98, 2.94, 9.81, 1235 kPa and with air-dried and oven-dried conditions. Results showed that measured Dp and ka values for the coarser (content. Further, compaction effort was much significant

  12. Recovery Act: Johnston Rhode Island Combined Cycle Electric Generating Plant Fueled by Waste Landfill Gas

    Energy Technology Data Exchange (ETDEWEB)

    Galowitz, Stephen

    2013-06-30

    systems, the Project established new national standards for best available control technology (BACT). 3) The Project will annually produce 365,292 MWh's of clean energy. 4) By destroying the methane in the landfill gas, the Project will generate CO{sub 2} equivalent reductions of 164,938 tons annually. The completed facility produces 28.3 MWnet and operates 24 hours a day, seven days a week.

  13. Landfill Barrier-Overview and Prospect

    Institute of Scientific and Technical Information of China (English)

    Zheng Liange; Zhao Yongsheng

    2000-01-01

    Landfill is the primary method of waste disposal. The increasing attention focused on the effect of landfill on environment prompts the development of environmental sound landfill system. As the key parts of landfill, the barrier system can provide impermeabilization of leachate and prevent biogas from escaping intotheenvironment. In recent years, the technology pertaining the barrier system developed rapidly. In this paper, new materials used in liners and new concept of barrier construction are reviewed; the mechanisms of leachate through clay liner and geomembrane, the calculation of leaks through liner and the effect of freezing/thaw on liner are discussed.

  14. Congenital anomalies and proximity to landfill sites.

    LENUS (Irish Health Repository)

    Boyle, E

    2004-01-01

    The occurrence of congenital anomalies in proximity to municipal landfill sites in the Eastern Region (counties Dublin, Kildare, Wicklow) was examined by small area (district electoral division), distance and clustering tendancies in relation to 83 landfills, five of which were major sites. The study included 2136 cases of congenital anomaly, 37,487 births and 1423 controls between 1986 and 1990. For the more populous areas of the region 50% of the population lived within 2-3 km of a landfill and within 4-5 km for more rural areas. In the area-level analysis, the standardised prevalence ratios, empirical and full Bayesian modelling, and Kulldorff\\'s spatial scan statistic found no association between the residential area of cases and location of landfills. In the case control analysis, the mean distance of cases and controls from the nearest landfill was similar. The odds ratios of cases compared to controls for increasing distances from all landfills and major landfills showed no significant difference from the baseline value of 1. The kernel and K methods showed no tendency of cases to cluster in relationship to landfills. In conclusion, congenital anomalies were not found to occur more commonly in proximity to municipal landfills.

  15. Thermodynamic Analysis of Methane-fueled Solid Oxide Fuel Cells Considering CO Electrochemical Oxidation

    Institute of Scientific and Technical Information of China (English)

    Qiong Sun; Keqing Zheng; Meng Ni⁎

    2014-01-01

    abstract Thermodynamic analyses in the literature have shown that solid oxide fuel cells (SOFCs) with proton conducting electrolyte (H-SOFC) exhibited higher performance than SOFC with oxygen ion conducting electrolyte (O-SOFC). However, these studies only consider H2 electrochemical oxidation and totally neglect the contribution of CO electrochemical oxidation in O-SOFC. In this short communication, a thermodynamic model is developed to compare the theoretically maximum efficiencies of H-SOFC and O-SOFC, considering the electrochemical oxidation of CO in O-SOFC anode. It is found that O-SOFC exhibits a higher maximum efficiency than H-SOFC due to the contribution from CO electrochemical oxidation, which is contrary to the common understanding of electrolyte effect on SOFC performance. The effects of operating temperature and fuel utilization factor on the theoretical efficiency of SOFC are also analyzed and discussed.

  16. Electricity Generation Characteristics of Microbial Fuel Cell ith Landfill Leachate as Fuel%以垃圾渗滤液为燃料的微生物燃料电池产电性能

    Institute of Scientific and Technical Information of China (English)

    张晓艳; 滕洪辉

    2011-01-01

    The double-chamber microbial fuel cell ( DCMFC ) with landfill leachate from some refuse dump of Siping City of Jilin Province as fuel was designed in the system with the bacteria in the titanium anode chamber separated from the titanium cathode chamber by a salt bridge. The effects of cathode chamber solution parameters on the electricity generation performance of DCMFC were researched. The results show that the DCMFC output power density is 12. 074 W/m2, open-circuit voltage is 1.13 V, internal resistance is 76. 868 O, under cathode chamber solution optimum conditions of 30 'C , 1.0 g/L H2O2, pH =2. 5, and 0. 5 g/L Na2SO4. After the DCMFC was continuously running for 30 days, the COD removal rate of landfill leachate reached to 95% , the adjust of cathode chamber operational parameters can improve the microbial fuel cell electricit generation.%以吉林省四平市某垃圾场渗滤液为燃料,纯钛板为负载微生物阳极和阴极,用盐桥转移电子方式组建双室微生物燃料电池(DCMFC).研究阴极室溶液电子受体质量浓度、pH值、温度等因素对输出功率密度、开路电压、内阻等电池性能的影响,并考察了对垃圾渗滤液的处理效果.实验结果表明,阴极溶液以1.0 g/L双氧水为电子受体,在pH=2.5、ρ(硫酸钠)=0.5 g/L、温度约为30 ℃的最佳实验条件下,该微生物燃料电池的输出功率密度达12.074 W/m2,开路电压为1.13 V,内阻为76.868 Ω.经过连续30 d的运行,垃圾渗滤液化学需氧量(COD)去除率达95%,表明选择恰当的阴极室溶液能提高微生物燃料电池的产电性能.

  17. Development of the utilization of combustible gas produced in existing sanitary landfills: Investigation of effects of air inclusion

    Science.gov (United States)

    1983-01-01

    The effects of nitrogen and oxygen on landfill gas operations are discussed. A combustible gas mixture composed of methane and carbon dioxide is generated in municipal solid waste landfills. A consequence of the collection of this fuel gas is the inclusion of some air in the collected product. The effects include increased collected and purification costs, reduction in the quality of the fuel gas produced, corrosion, explosion hazards, and interference with odorant systems. The scope of such effects was determined by using landfill data of a gas recovery site as a basis. Useful supplemental fuel gas may be recovered despite the inclusion of air. Recommendations are made for establishing limits for nitrogen and oxygen content and minimizing the costs associated with their presence.

  18. Hydrogen production for fuel cells by autothermal reforming of methane over sulfide nickel catalyst on a gamma alumina support

    Science.gov (United States)

    Hoang, D. L.; Chan, S. H.; Ding, O. L.

    Experimental and modelling studies have been conducted on catalytic autothermal reforming (ATR) of methane for hydrogen production over a sulfide nickel catalyst on a gamma alumina support. The experiments are performed with different feedstock under thermally neutral conditions. The results show that the performance of the reformer is dependent on the molar air-to-fuel ratio (A/F), the molar water-to-fuel ratio (W/F) and the flowrate of the feedstock mixture. The optimum conditions for high methane conversion and high hydrogen yield are A/F = 3-3.5, W/F = 2-2.5 and a fuel flowrate below 120-250 l h -1. Under these conditions, a methane conversion of 95-99% and a hydrogen yield of 39-41% on a dry basis can be achieved and 1 mole of methane can produce 1.8 moles of hydrogen at an equilibrium reactor temperature of not exceeding 850 °C. A two-dimensional reactor model is developed to simulate the conversion behaviour of the reactor for further study of the reforming process. The model includes all aspects of the major chemical kinetics and the heat and mass transfer phenomena in the reactor. The predicted results are successfully validated with experimental data.

  19. Identification of Methanogens and Controls on Methane Production in Incubations of Natural Methane Seep Sediments

    Science.gov (United States)

    Kevorkian, R.; Lloyd, K. G.

    2014-12-01

    Methane, the most abundant hydrocarbon in Earth's atmosphere, is produced in large quantities in sediments underlying the world's oceans. Very little of this methane makes it to surface sediments as it is consumed by Anaerobic Methanotrophs (ANME's) in consortia with Sulfate Reducing Bacteria (SRB). Less is known about which organisms are responsible for methane production in marine sediments, and whether that production is under thermodynamic control based on hydrogen concentrations. Although ANMEs have been found to be active in methanogenic sediments and incubations, it is currently unknown whether they are able to grow in methanogenic conditions. We demonstrated with bottle incubations of methane seep sediment taken from Cape Lookout Bight, NC, that hydrogen controls methane production. While sulfate was present the hydrogen concentration was maintained at below 2 nM. Only after the depletion of sulfate allowed hydrogen concentrations to rise above 5 nM did we see production of methane. The same sediments when spiked with methane gas demonstrated its complete removal while sulfate reduction occurred. Quantitative PCR shows that ANME-2 and ANME-1 increase in 16S copy number as methane increases. Total direct cell counts demonstrate a decline in cells with the decrease of sulfate until a recovery corresponding with production of methane. Our results strongly suggest that hydrogen concentrations influence what metabolic processes can occur in marine sediments, and that ANME-1 and ANME-2 are able to grow on the energy provided from methane production.

  20. Kinetics of methane fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Y. R.; Hashimoto, A. G.

    1978-01-01

    The kinetics on methane fermentation are described using published data for livestock residue, sewage sludge, and municipal refuse. Methods are presented to determine the kinetic constants and the finally attainable methane production using steady-state methane production data. The effects of temperature, loading rate, and influent substrate concentration on methane fermentation kinetics are discussed. These relationships were used to predict the rate of methane production of a pilot-scale fermentor with excellent results.

  1. Landfill gas generation and emission at danish waste disposal sites receiving waste with a low organic waste content

    DEFF Research Database (Denmark)

    Mou, Zishen; Scheutz, Charlotte; Kjeldsen, Peter

    2015-01-01

    two models are multi-phase models, which defines waste fractions into traditional MSW and low-organic waste categories, respectively. Both the LandGEM and the IPCC model estimated significantly larger methane (CH4) generation in comparison to the Afvalzorg model. The Afvalzorg model could better show...... the influence of not only the total disposed waste amount, but also various waste categories, and was found more suitable to estimate LFG generation from landfills receiving low-organic waste. Four major waste categories currently being disposed at Danish landfills (mixed bulky, shredder, dewatered sludge...... and street cleansing waste) and temporarily stored combustible waste were sampled and characterized in terms of TS, VS, TC, TOC, and biochemical methane potential (BMP). Decay rates (k values), were determined by conducting anaerobic degradation experiments and applying FOD equations to the experimental...

  2. MONITORING APPROACHES FOR BIOREACTOR LANDFILLS - Report

    Science.gov (United States)

    Experimental bioreactor landfill operations at operating Municipal Solid Waste (MSW) landfills can be approved under the research development and demonstration (RD&D) provisions of 30CFR 258.4. To provide a basis for consistent data collection for future decision-making in suppor...

  3. Imaging scatterers in landfills using seismic interferometry

    NARCIS (Netherlands)

    Konstantaki, L.A.; Dragnov, D.S.; Heimovaara, T.J.; Ghose, R.

    2013-01-01

    A significant problem with landfills is their aftercare period. A landfill is considered to be safe for the environment only after a relatively long period of time. Until it reaches such a condition, it has to be periodically treated. Not only are treatments very expensive, but they could be dangero

  4. Quantifying capital goods for waste landfilling

    DEFF Research Database (Denmark)

    Brogaard, Line Kai-Sørensen; Stentsøe, Steen; Willumsen, Hans Christian

    2013-01-01

    Materials and energy used for construction of a hill-type landfill of 4 million m3 were quantified in detail. The landfill is engineered with a liner and leachate collections system, as well as a gas collection and control system. Gravel and clay were the most common materials used, amounting to ...

  5. GEOTECHNICAL DESIGN OF SOLID WASTE LANDFILL SITES

    Directory of Open Access Journals (Sweden)

    Suat AKBULUT

    2003-02-01

    Full Text Available Solid waste landfills are important engineering structures for protection of wastes, decrease of environmental pollution, and especially prevention of soil and water pollution. Solid wastes should conveniently be maintained in landfill areas to control environmental pollution caused by waste disposals. Until the middle of this century clay liners were used for maintenance of waste disposal, but it was observed that these liner systems were insufficient. Today thinner and less permeable liner systems are constructed by using synthetic materials. In this study, by evaluating the waste landfills, site assessment of landfills and construction of natural and synthetic liner systems were summarized respectively, and especially the design properties of these systems were examined intensively. Also, leachate collection and removal facilities, landfill gas collection unites, and final cover unites were evaluated in a detailed way.

  6. Biogeochemistry of landfill leachate plumes

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Kjeldsen, Peter; Bjerg, Poul Løgstrup

    2001-01-01

    is on dissolved organic matter, xenobiotic organic compounds, inorganic macrocomponents as anions and cations, and heavy metals. Laboratory as well as field investigations are included. This review is an up-date of an earlier comprehensive review. The review shows that most leachate contamination plumes...... the behavior of the contaminants in the plume as the leachate migrates away from the landfill. Diverse microbial communities have been identified in leachate plumes and are believed to be responsible for the redox processes. Dissolved organic C in the leachate, although it appears to be only slowly degradable...

  7. Toxicological characterization of a novel wastewater treatment process using EDTA-Na2Zn as draw solution (DS) for the efficient treatment of MBR-treated landfill leachate.

    Science.gov (United States)

    Niu, Aping; Ren, Yi-Wei; Yang, Li; Xie, Shao-Lin; Jia, Pan-Pan; Zhang, Jing-Hui; Wang, Xiao; Li, Jing; Pei, De-Sheng

    2016-07-01

    Landfill leachate has become an important source of environmental pollution in past decades, due to the increase of waste volume. Acute toxic and genotoxic hazards to organisms can be caused by landfill leachate. Thus, how to efficiently recover water from landfill leachate and effectively eliminate combined toxicity of landfill leachate are the most pressing issues in waste management. In this study, EDTA-Na2Zn as draw solution (DS) was used to remove the toxicity of membrane bioreactor-treated landfill leachate (MBR-treated landfill leachate) in forward osmosis (FO) process, and nanofiltration (NF) was designed for recovering the diluted DS. Zebrafish and human cells were used for toxicity assay after the novel wastewater treatment process using EDTA-Na2Zn as DS. Results showed that the water recovery rate of MBR-treated landfill leachate (M-LL) in FO membrane system could achieve 66.5% and 71.2% in the PRO and FO mode respectively, and the diluted DS could be efficiently recovered by NF. Toxicity tests performed by using zebrafish and human cells showed that M-LL treated by EDTA-Na2Zn had no toxicity effect on zebrafish larvae and human cells, but it had very slight effect on zebrafish embryos. In conclusion, all results indicated that EDTA-Na2Zn as DS can effectively eliminate toxicity of landfill leachate and this method is economical and eco-friendly for treatment of different types of landfill leachate.

  8. Variations of dominant microbial populations in groundwater in response to the leachate from Laogang Landfill

    Institute of Scientific and Technical Information of China (English)

    TIAN Yang-jie; YANG Hong; LI Dao-tang; LIN Zhi-xin

    2005-01-01

    Temporal changes of dominant microbial populations in groundwater in response to the leachate from Shanghai Laogang Landfill were investigated. Concentrations of dissolved redox-relevant species in groundwater suggested that the dominating redox process had changed from denitrification to methane-production/sulfate-reduction due to landfilling. Dominant microbial populations were determined using restriction fragment length polymorphism(RFLP) analyses of 16S rRNA gene libraries, which were further studied by sequencing and phylogenetic analyses. The results indicated that obvious shifts of dominant microbial populations had occurred in groundwater in response to the pollution of leachate. The closest relatives of some dominant clones are accordant with the dominating redox processes determined by hydrochemical analyses, based on the GenBank's indications on the ability to perform redox reactions.

  9. An anaerobic field injection experiment in a landfill leachate plume (Grindsted, Denmark)

    DEFF Research Database (Denmark)

    Albrechtsen, Hans-Jørgen; Bjerg, Poul Løgstrup; Ludvigsen, L.

    1999-01-01

    Redox conditions may be environmental factors which affect the fate of the xenobiotic organic compounds. Therefore the redox conditions were characterized in an anaerobic, leachate-contaminated aquifer 15–60 m downgradient from the Grindsted Landfill, Denmark, where an field injection experiment...... to the sediment samples. Samples were investigated with respect to groundwater chemistry, including hydrogen and volatile fatty acids (VFAs) and sediment geochemistry, and bioassays were performed. The groundwater chemistry, including redox sensitive species for a large number of samples, varied over time during...... the experimental period of 924 days owing to variations in the leachate from the landfill. However, no indication of change in the redox environment resulting from the field injection experiment or natural variation was observed in the individual sampling points. The methane, Fe(II), hydrogen, and VFA groundwater...

  10. Landfill gas (LFG) processing via adsorption and alkanolamine absorption

    Energy Technology Data Exchange (ETDEWEB)

    Gaur, Ankur; Park, Jin-Won; Song, Ho-Jun; Park, Jong-Jin [Department of Chemical and Biomolecular Engineering, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul 120-749 (Korea); Maken, Sanjeev [Department of Chemistry, Deenbandhu Chhotu Ram University of Science and Technology, Murthal-131 039, Haryana (India)

    2010-06-15

    Landfill gas (LFG) was upgraded to pure methane using the adsorption and absorption processes. Different toxic compounds like aromatics and chlorinated compounds were removed using granular activated carbon. The activated carbon adsorbed toxic trace components in the following order: carbon tetrachloride > toluene > chloroform > xylene > ethylbenzene > benzene > trichloroethylene {approx} tetrachloroethylene. After removing all trace components, the gas was fed to absorption apparatus for the removal of carbon dioxide (CO{sub 2}). Two alkanolamines, monoethanol amine (MEA) and diethanol amine (DEA) were used for the removal of CO{sub 2} from LFG. The maximum CO{sub 2} loading is obtained for 30 wt.% MEA which is around 2.9 mol L{sup -} {sup 1} of absorbent solution whereas for same concentration of DEA it is around 1.66 mol L {sup -} {sup 1} of solution. 30 wt% MEA displayed a higher absorption rate of around 6.64 x 10{sup -} {sup 5} mol L{sup -} {sup 1} min{sup -} {sup 1}. DEA displayed a higher desorption rate and a better cyclic capacity as compared to MEA. Methane obtained from this process can be further used in the natural gas network for city. (author)

  11. Decomposition and carbon storage of selected paper products in laboratory-scale landfills.

    Science.gov (United States)

    Wang, Xiaoming; De la Cruz, Florentino B; Ximenes, Fabiano; Barlaz, Morton A

    2015-11-01

    The objective of this study was to measure the anaerobic biodegradation of different types of paper products in laboratory-scale landfill reactors. The study included (a) measurement of the loss of cellulose, hemicellulose, organic carbon, and (b) measurement of the methane yields for each paper product. The test materials included two samples each of newsprint (NP), copy paper (CP), and magazine paper (MG), and one sample of diaper (DP). The methane yields, carbon storage factors and the extent of cellulose and hemicellulose decomposition all consistently show that papers made from mechanical pulps (e.g., NPs) are less degradable than those made from chemical pulps where essentially all lignin was chemically removed (e.g., CPs). The diaper, which is not only made from chemical pulp but also contains some gel and plastic, exhibited limited biodegradability. The extent of biogenic carbon conversion varied from 21 to 96% among papers, which contrasts with the uniform assumption of 50% by the Intergovernmental Panel on Climate Change (IPCC) for all degradable materials discarded in landfills. Biochemical methane potential tests also showed that the solids to liquid ratio used in the test can influence the results.

  12. Quantifying methane emission from fugitive sources by combining tracer release and downwind measurements – A sensitivity analysis based on multiple field surveys

    DEFF Research Database (Denmark)

    Mønster, Jacob; Samuelsson, Jerker; Kjeldsen, Peter

    2014-01-01

    Using a dual species methane/acetylene instrument based on cavity ring down spectroscopy (CRDS), the dynamic plume tracer dispersion method for quantifying the emission rate of methane was successfully tested in four measurement campaigns: (1) controlled methane and trace gas release with different...... trace gas configurations, (2) landfill with unknown emission source locations, (3) landfill with closely located emission sources, and (4) comparing with an Fourier transform infrared spectroscopy (FTIR) instrument using multiple trace gasses for source separation. The new real-time, high precision...... instrument can measure methane plumes more than 1.2km away from small sources (about 5kgh−1) in urban areas with a measurement frequency allowing plume crossing at normal driving speed. The method can be used for quantification of total methane emissions from diffuse area sources down to 1kg per hour and can...

  13. Attenuation of Landfill Leachate In Unsaturated Sandstone

    Science.gov (United States)

    Butler, A. P.; Brook, C.; Godley, A.; Lewin, K.; Young, C. P.

    Landfill leachate emanating from old "dilute and disperse" sites represents a potential (and in many cases actual) threat to the integrity of groundwater. Indeed, this concern has been included in EU legislation (80/86/EEC), where key contaminants (e.g. ammonia, various toxic organic compounds and heavy metals) are explicitly highlighted in terms of their impact on groundwater. In the UK, whilst there are a substantial number of unlined landfills sited on major aquifers, many of these are in locations where there is a substantial unsaturated zone. Thus, there exists the opportunity for the modification and attenuation of contaminants prior to it encountering the water table. An understanding of likely changes in leachate content and concentrations at such sites will enable a more comprehensive assessment of the potential risks and liabilities posed by such sites to be evaluated. The Burntstump landfill, situated 8 km north of Nottingham (UK), is sited on an outcrop of Sherwood sandstone. The fine friable sand has been quarried since the 1960s and the excavated volume used to store municipal waste. Filling at the site commenced in the mid 1970s and originally was unlined. In 1978 the first of what was to become a series of boreholes was installed within an area of roughly 5 m radius over one of the original waste cells. Cores of the waste and underlying sandstone were extracted and analysed for a range of physical and chemical parameters. The most recent set of analyses were obtained in 2000. The series of investigations therefore provide an important record of leachate migration and modification through the unsaturated zone for over twenty years. The progression of the leachate front is clearly delineated by the chloride concentration profile with an average velocity of around 1.6 m.yr-1. Combining this value with an average (and reasonably uniform) measured moisture content of about 7% gives a mean inter-granular specific discharge of 110 mm.yr-1. An interesting

  14. Evaluation of the Oedometer Tests of Municipal Landfill Waste Material

    Directory of Open Access Journals (Sweden)

    Imre Emőke

    2014-07-01

    Full Text Available The aim of the ongoing research is (i to develop a new biodegradation landfill technique so that the landfill gas production could be controlled and the utilisation of the landfill gas could economically be optimized, (ii to plan the energy utilisation of the landfill including individual and combined solutions (solar, wind, geothermal energy, energy storage using methanol etc.. [1, 2, 3

  15. [Effect of operational modes on community structure of type I methanotroph in the cover soil of municipal solid waste landfill].

    Science.gov (United States)

    Yu, Ting; He, Pin-Jing; Lü, Fan; Shao, Li-Ming

    2008-10-01

    Type I methanotroph is crucial for methane oxidization and it responses fast to the changes in environment. In this study, 16S rDNA-based denaturing gradient gel electrophoresis (DGGE) gene fingerprint technology was applied to investigate the effect of operational modes, i. e. high-density polyethylene liner (HDPE) isolation or subsurface irrigation of landfill leachate and vegetation, on community structure and diversity of type I methanotroph in soils covering municipal solid waste landfill. 16S rDNA based phylogenetic analysis reveals type I methanotroph in all tested soils belongs to Methylobacter. According to Shannon-Wiener diversity index and principal component analysis, landfill leachate subsurface irrigation and vegetation have more impact on type I methanotroph community structure and diversity than HDPE liner isolation does, and they reduce type I methanotroph diversity. Leachate irrigation is supposed to inhibit the growth of Methylobacter population. Community structure of type I methanotroph in landfill cover soil isolated by HDPE, i.e. invaded by landfill gas, shifts during long-term gas interference. When cover age is 1.5 years old, Shannon-Wiener diversity index of type I methanotroph reaches its maximum.

  16. Performance of alternative oxide anodes for the electrochemical oxidation of hydrogen and methane in solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Tu, H.; Apfel, H.; Stimming, U. [Department of Physics E19, Technical University of Munich, James-Franck-Strasse 1, D-85748 Garching (Germany)

    2006-07-15

    The electrode performances of the alternative oxides: La{sub 0.05}Ca{sub 0.95}Cr{sub 0.05}Ti{sub 0.95}O{sub 3-{delta}}-8YSZ and Ce{sub 0.8}TM{sub 0.2}O{sub 2-{delta}}(TM=Mn, Co) for the direct electrochemical oxidation of methane are investigated to assess their potential as anode materials for efficient methane conversion in a SOFC. The electrochemical oxidation of hydrogen was also studied, for comparison. The oxides are characterised electrochemically with impedance spectroscopy in the frequency range from 10 mHz to 1MHz, using a three-electrode geometry. They are compared to a standard Ni/8YSZ anode for the electrochemical oxidation of hydrogen. It is found that La{sub 0.05}Ca{sub 0.95}Cr{sub 0.05}Ti{sub 0.95}O{sub 3-{delta}}-8YSZ demonstrates a poor electrochemical activity in both hydrogen and methane. However, the electrochemical activity of Ce{sub 0.8}Mn{sub 0.2}O{sub 2-{delta}} is promising, but the electronic conductivity needs to be increased, e.g., by adding a conducting oxide, before it can be used as an anode material in a SOFC. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  17. Inferred performance of surface hydraulic barriers from landfill operational data

    Energy Technology Data Exchange (ETDEWEB)

    Gross, B.A. [GeoSyntec Consultants, Austin, TX (United States); Bonaparte, R.; Othman, M.A. [GeoSyntec Consultants, Atlanta, GA (United States)

    1997-12-31

    There are few published data on the field performance of surface hydraulic barriers (SHBs) used in waste containment or remediation applications. In contrast, operational data for liner systems used beneath landfills are widely available. These data are frequently collected and reported as a facility permit condition. This paper uses leachate collection system (LCS) and leak detection system (LDS) liquid flow rate and chemical quality data collected from modem landfill double-liner systems to infer the likely hydraulic performance of SHBs. Operational data for over 200 waste management unit liner systems are currently being collected and evaluated by the authors as part of an ongoing research investigation for the United States Environmental Protection Agency (USEPA). The top liner of the double-liner system for the units is either a geomembrane (GMB) alone, geomembrane overlying a geosynthetic clay liner (GMB/GCL), or geomembrane overlying a compacted clay liner (GMB/CCL). In this paper, select data from the USEPA study are used to: (i) infer the likely efficiencies of SHBs incorporating GMBs and overlain by drainage layers; and (ii) evaluate the effectiveness of SHBs in reducing water infiltration into, and drainage from, the underlying waste (i.e., source control). SHB efficiencies are inferred from calculated landfill liner efficiencies and then used to estimate average water percolation rates through SHBs as a function of site average annual rainfall. The effectiveness of SHBs for source control is investigated by comparing LCS liquid flow rates for open and closed landfill cells. The LCS flow rates for closed cells are also compared to the estimated average water percolation rates through SHBs presented in the paper.

  18. Atmospheric Ozone and Methane in a Changing Climate

    Directory of Open Access Journals (Sweden)

    Ivar S. A. Isaksen

    2014-07-01

    Full Text Available Ozone and methane are chemically active climate-forcing agents affected by climate–chemistry interactions in the atmosphere. Key chemical reactions and processes affecting ozone and methane are presented. It is shown that climate-chemistry interactions have a significant impact on the two compounds. Ozone, which is a secondary compound in the atmosphere, produced and broken down mainly in the troposphere and stratosphre through chemical reactions involving atomic oxygen (O, NOx compounds (NO, NO2, CO, hydrogen radicals (OH, HO2, volatile organic compounds (VOC and chlorine (Cl, ClO and bromine (Br, BrO. Ozone is broken down through changes in the atmospheric distribution of the afore mentioned compounds. Methane is a primary compound emitted from different sources (wetlands, rice production, livestock, mining, oil and gas production and landfills.Methane is broken down by the hydroxyl radical (OH. OH is significantly affected by methane emissions, defined by the feedback factor, currently estimated to be in the range 1.3 to 1.5, and increasing with increasing methane emission. Ozone and methane changes are affected by NOx emissions. While ozone in general increase with increases in NOx emission, methane is reduced, due to increases in OH. Several processes where current and future changes have implications for climate-chemistry interactions are identified. It is also shown that climatic changes through dynamic processes could have significant impact on the atmospheric chemical distribution of ozone and methane, as we can see through the impact of Quasi Biennial Oscillation (QBO. Modeling studies indicate that increases in ozone could be more pronounced toward the end of this century. Thawing permafrost could lead to important positive feedbacks in the climate system. Large amounts of organic material are stored in the upper layers of the permafrost in the yedoma deposits in Siberia, where 2 to 5% of the deposits could be organic material

  19. Climate co-benefits of energy recovery from landfill gas in developing Asian cities: a case study in Bangkok.

    Science.gov (United States)

    Menikpura, S N M; Sang-Arun, Janya; Bengtsson, Magnus

    2013-10-01

    Landfilling is the most common and cost-effective waste disposal method, and it is widely applied throughout the world. In developing countries in Asia there is currently a trend towards constructing sanitary landfills with gas recovery systems, not only as a solution to the waste problem and the associated local environmental pollution, but also to generate revenues through carbon markets and from the sale of electricity. This article presents a quantitative assessment of climate co-benefits from landfill gas (LFG) to energy projects, based on the case of Bangkok Metropolitan Administration, Thailand. Life cycle assessment was used for estimating net greenhouse gas (GHG) emissions, considering the whole lifespan of the landfill. The assessment found that the total GHG mitigation of the Bangkok project would be 471,763 tonnes (t) of carbon dioxide (CO(2))-equivalents (eq) over its 10-year LFG recovery period.This amount is equivalent to only 12% of the methane (CH(4)) generated over the whole lifespan of the landfill. An alternative scenario was devised to analyse possible improvement options for GHG mitigation through LFG-to-energy recovery projects. This scenario assumes that LFG recovery would commence in the second year of landfill operation and gas extraction continues throughout the 20-year peak production period. In this scenario, GHG mitigation potential amounted to 1,639,450 tCO(2)-eq during the 20-year project period, which is equivalent to 43% of the CH(4) generated throughout the life cycle. The results indicate that with careful planning, there is a high potential for improving the efficiency of existing LFG recovery projects which would enhance climate co-benefits, as well as economic benefits. However, the study also shows that even improved gas recovery systems have fairly low recovery rates and, in consequence, that emissions of GHG from such landfills sites are still considerable.

  20. Fiber Methane Gas Sensor and Its Application in Methane Outburst Prediction in Coal Mine

    Institute of Scientific and Technical Information of China (English)

    Jia-Sheng Ni; Jun Chang; Tong-Yu Liu; Yan-Fang Li; Yan-Jie Zhao; Qian Wang

    2008-01-01

    Fiber optic methane gas detecting system based on distributed feedback (DFB) laser wavelength scanning technique is demonstrated. Wavelength scan of methane absorption peak at 1665.9 nm is realized by saw tooth modulation of current which is injected to DFB laser. A reference methane gas cell is used to find the methane absorption peak around 1666 rim, and normalization is used to reduce the outside affection such as power drift, fiber loss. Concentration is got by arithmetic processing absorption coefficient of the methane gas. In-situ test is carried out in coal mine and long time precision of 0.05% is achieved. Some spot data of coal mine is introduced. By the system, methane outburst can be measured.

  1. Estimating dispersed and point source emissions of methane in East Anglia: results and implications

    Science.gov (United States)

    Harris, Neil; Connors, Sarah; Hancock, Ben; Jones, Pip; Murphy, Jonathan; Riddick, Stuart; Robinson, Andrew; Skelton, Robert; Manning, Alistair; Forster, Grant; Oram, David; O'Doherty, Simon; Young, Dickon; Stavert, Ann; Fisher, Rebecca; Lowry, David; Nisbet, Euan; Zazzeri, Guilia; Allen, Grant; Pitt, Joseph

    2016-04-01

    We have been investigating ways to estimate dispersed and point source emissions of methane. To do so we have used continuous measurements from a small network of instruments at 4 sites across East Anglia since 2012. These long-term series have been supplemented by measurements taken in focussed studies at landfills, which are important point sources of methane, and by measurements of the 13C:12C ratio in methane to provide additional information about its sources. These measurements have been analysed using the NAME InTEM inversion model to provide county-level emissions (~30 km x ~30 km) in East Anglia. A case study near a landfill just north of Cambridge was also analysed using a Gaussian plume model and the Windtrax dispersion model. The resulting emission estimates from the three techniques are consistent within the uncertainties, despite the different spatial scales being considered. A seasonal cycle in emissions from the landfill (identified by the isotopic measurements) is observed with higher emissions in winter than summer. This would be expected from consideration of the likely activity of methanogenic bacteria in the landfill, but is not currently represented in emission inventories such as the UK National Atmospheric Emissions Inventory. The possibility of assessing North Sea gas field emissions using ground-based measurements will also be discussed.

  2. Microbial activity in the landfill soil.

    Science.gov (United States)

    Brzezinska, M Swiontek; Burkowska, A; Walczak, M

    2012-01-01

    The research objective was to determine the activity of microorganisms in the soil exposed to direct influence of a landfill, as well as in the soil beyond its influence. Fluorescein diacetate (FDA) hydrolytic activity and respiration in the soil were determined. The highest number of cultivated bacteria was recorded at the site located within the zone of direct influence exerted by the landfill, whereas the least amount was found at a distance of 1000 metres from the landfill. In contrast, the largest numbers of molds were observed in the soil at a distance of 1000 m from the headquarters of the landfill. The highest FDA hydrolytic activity and biological oxygen demand (BOD5) were recorded in the soil by the headquarters of the landfill, and the least parameters were revealed at a distance of 1000 m from the landfill. It was found a high correlation between the number of bacteria and FDA hydrolytic activity of soil and BOD5 in the north-eastern of the landfill. However, in the same place, there is a low correlation between the number of molds, and FDA hydrolytic activity of soil and BOD5.

  3. Closure Alternatives for Municipal Waste Landfills.Study Case: Municipal Waste Landfill Medias,Sibiu County

    Directory of Open Access Journals (Sweden)

    MIHĂIESCU R.

    2010-12-01

    Full Text Available In the recent decades, the environmental impact produced by municipal solid wastes has received specialattention. All new EU countries are involved in the process of implementation of the European Council Directive31/99/EC on the landfill of waste in the European Union. As consequence National legislation, adapted to fit the EUrequirements, focuses on integrated waste management and environmental control of municipal solid waste landfills,from start-up to closure and assimilation into the environment. In Romania, by Government decision, HG 349/2005,was established the obligatoriness of closing unconform waste landfills located in urban areas starting at July 2009. Asconsequence the owner of municipal waste landfill Medias started the proceedings of closure for the landfill. The aim ofthis study is to compare, from an environmental point of view, different alternatives for the closure of the municipalsolid waste landfill Somard-Medias (Romania.

  4. Dispersion forces in methane

    NARCIS (Netherlands)

    Lekkerkerker, H.N.W.; Coulon, P.; Luyckx, R.

    1977-01-01

    The coefficients of the R-6 and R-7 terms in the series representation of the dispersion interaction between two methane molecules and between methane and helium, neon and argon are calculated by a variation method.

  5. DEMONSTRATION OF FUEL CELLS TO RECOVER ENERGY FROM LANDFILL GAS - PHASE III. DEMONSTRATION TESTS - PHASE IV. GUIDELINES AND RECOMMENDATIONS- VOLUME 1. TECHNICAL REPORT

    Science.gov (United States)

    The report summarizes the results of a four-phase program to demonstrate that fuel cell energy recovery using a commercial phosphoric acid fuel cell is both environmentally sound and commercially feasible. Phase I, a conceptual design and evaluation study, addressed the technical...

  6. Thermophilic methane production and oxidation in compost.

    Science.gov (United States)

    Jäckel, Udo; Thummes, Kathrin; Kämpfer, Peter

    2005-04-01

    Methane cycling within compost heaps has not yet been investigated in detail. We show that thermophilic methane oxidation occurred after a lag phase of up to one day in 4-week old, 8-week old and mature (>10-week old) compost material. The potential rate of methane oxidation was between 2.6 and 4.1 micromol CH4(gdw)(-1)h(-1). Profiles of methane concentrations within heaps of different ages indicated that 46-98% of the methane produced was oxidised by methanotrophic bacteria. The population size of thermophilic methanotrophs was estimated at 10(9) cells (gdw)(-1), based on methane oxidation rates. A methanotroph (strain KTM-1) was isolated from the highest positive step of a serial dilution series. This strain belonged to the genus Methylocaldum, which contains thermotolerant and thermophilic methanotrophs. The closest relative organism on the basis of 16S rRNA gene sequence identity was M. szegediense (>99%), a species originally isolated from hot springs. The temperature optimum (45-55 degrees C) for methane oxidation within the compost material was identical to that of strain KTM-1, suggesting that this strain was well adapted to the conditions in the compost material. The temperatures measured in the upper layer (0-40 cm) of the compost heaps were also in this range, so we assume that these organisms are capable of effectively reducing the potential methane emissions from compost.

  7. Comparison of the methane oxidation rate in four media

    Directory of Open Access Journals (Sweden)

    Juliana Lundgren Rose

    2012-06-01

    Full Text Available Landfill gas emissions are one of the main sources of anthropogenic methane (CH4, a major greenhouse gas. In this paper, an economically attractive alternative to minimize greenhouse gas emissions from municipal solid waste landfills was sought. This alternative consists in special biofilters as landfill covers with oxidative capacity in the presence of CH4. To improve the quality/cost ratio of the project, compost was chosen as one of the cover substrates and soil (Typic red yellow-silt-clay Podzolic as the other. The performance of four substrates was studied in laboratory experiments: municipal solid waste (MSW compost, soil, and two soil-compost at different proportions. This study aimed to evaluate the suitability and environmental compatibility as a means of CH4 oxidation in biofilters. Four biofilters were constructed in 60 cm PVC tubes with an internal diameter of 10 cm. Each filter contained 2.3 L of oxidizing substrate at the beginning of the experiment. The gas used was a mixture of CH4 and air introduced at the bottom of each biofilter, at a flow of 150 mL min-1, by a flow meter. One hundred days after the beginning of the experiment, the best biofilter was the MSW compost with an oxidation rate of 990 g m-3 day-1 , corresponding to an efficiency of 44 %. It can be concluded that the four substrates studied have satisfactory oxidative capacity, and the substrates can be used advantageously as cover substrate of MSW landfills.

  8. Hydrogen stable isotopic constraints on methane emissions from oil and gas extraction in the Colorado Front Range, USA

    Science.gov (United States)

    Townsend-Small, A.; Botner, E. C.; Jimenez, K.; Blake, N. J.; Schroeder, J.; Meinardi, S.; Barletta, B.; Simpson, I. J.; Blake, D. R.; Flocke, F. M.; Pfister, G.; Bon, D.; Crawford, J. H.

    2015-12-01

    The climatic implications of a shift from oil and coal to natural gas depend on the magnitude of fugitive emissions of methane from the natural gas supply chain. Attempts to constrain methane emissions from natural gas production regions can be confounded by other sources of methane. Here we demonstrate the utility of stable isotopes, particularly hydrogen isotopes, for source apportionment of methane emissions. The Denver, Colorado area is home to a large oil and gas field with both conventional oil and gas wells and newer hydraulic fracturing wells. The region also has a large metropolitan area with several landfills and a sizable cattle population. As part of the DISCOVER-AQ and FRAPPE field campaigns in summer 2014, we collected three types of canister samples for analysis of stable isotopic composition of methane: 1), samples from methane sources; 2), samples from two stationary ground sites, one in the Denver foothills, and one in an oil and gas field; and 3), from the NCAR C-130 aircraft in samples upwind and downwind of the region. Our results indicate that hydrogen isotope ratios are excellent tracers of sources of methane in the region, as we have shown previously in California and Texas. Use of carbon isotope ratios is complicated by the similarity of natural gas isotope ratios to that of background methane. Our results indicate that, despite the large amount of natural gas production in the region, biological sources such as cattle feedlots and landfills account for at least 50% of total methane emissions in the Front Range. Future work includes comparison of isotopes and alkane ratios as tracers of methane sources, and calculation of total methane fluxes in the region using continuous measurements of methane concentrations during aircraft flights.

  9. Landfills in the Western United States

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Locations of landfills and waste transfer stations in 11 western states. Data was obtained from state and federal agencies in GIS, tabular, and map format.

  10. 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.

  11. Municipal landfill sites as sources of microorganisms potentially pathogenic to humans.

    Science.gov (United States)

    Kalwasińska, Agnieszka; Burkowska, Aleksandra

    2013-05-01

    The present research was aimed at assessing the quality of air and soil on the premises and in the vicinity of the municipal landfill sites in Toruń with regard to the presence of pathogenic bacteria, potentially dangerous to humans. Air samples (the impaction method using a MAS-100 impactor) and soil samples were collected from seven sampling sites including the operating and closed landfill cells, sampling sites located near leachate ponds, and sampling sites located outside the above premises. The research also involved assessing microbial air contamination in three indoor spaces on the premises of the landfill sites. Microbial tests involved the determination of the number of culturable mesophilic, mannitol-positive, and α- and β-hemolytic bacteria in the air, determination of the number of coliform bacteria, spore-forming Clostridium perfringens in soil, and the presence of Salmonella in soil. The results indicate that bioaerosol emitted by this municipal facility is the source of hemolytic bacteria (≤ 300 CFU m(-3) of air), as well as of pathogenic bacteria (Pseudomonas aeruginosa and Bacillus subtilis). The highest risk of exposure to biological agents was determined in the sorting facility. Over sixty percent of air samples in this sampling site presented high pollution degree with mesophilic bacteria (500-2000 CFU m(-3) of air) and over one fourth of air samples presented very high pollution degree (>2000 CFU m(-3) of air). Indoor air in other rooms was considered highly/moderately contaminated (100-2000 CFU m(-3) of air). The highest risk related to the presence of Salmonella, Clostridium perfringens, and coliform bacteria in soil was determined at the operating landfill cell and near the leachate pond of the closed landfill cell. At the operating landfill cell the total coli ranged from 4-1226 MPN g(-1) of dry mass of soil and Clostridium perfringens ranged from landfill sites in densely populated areas, and emphasize the need for regular monitoring

  12. Landfill mining: Developing a comprehensive assessment method.

    Science.gov (United States)

    Hermann, Robert; Wolfsberger, Tanja; Pomberger, Roland; Sarc, Renato

    2016-11-01

    In Austria, the first basic technological and economic examinations of mass-waste landfills with the purpose to recover secondary raw materials have been carried out by the 'LAMIS - Landfill Mining Österreich' pilot project. A main focus of its research, and the subject of this article, is the first conceptual design of a comprehensive assessment method for landfill mining plans, including not only monetary factors (like costs and proceeds) but also non-monetary ones, such as the concerns of adjoining owners or the environmental impact. Detailed reviews of references, the identification of influences and system boundaries to be included in planning landfill mining, several expert workshops and talks with landfill operators have been performed followed by a division of the whole assessment method into preliminary and main assessment. Preliminary assessment is carried out with a questionnaire to rate juridical feasibility, the risk and the expenditure of a landfill mining project. The results of this questionnaire are compiled in a portfolio chart that is used to recommend, or not, further assessment. If a detailed main assessment is recommended, defined economic criteria are rated by net present value calculations, while ecological and socio-economic criteria are examined in a utility analysis and then transferred into a utility-net present value chart. If this chart does not support making a definite statement on the feasibility of the project, the results must be further examined in a cost-effectiveness analysis. Here, the benefit of the particular landfill mining project per capital unit (utility-net present value ratio) is determined to make a final distinct statement on the general benefit of a landfill mining project.

  13. Latest on Mobile Methane Measurements with Fast Open-Path Technology: Experiences, Opportunities & Perspectives

    Science.gov (United States)

    Burba, George; Anderson, Tyler; Ediger, Kevin; von Fischer, Joseph; Gioli, Beniamino; Ham, Jay; Hupp, Jason; Kohnert, Katrin; Larmanou, Eric; Levy, Peter; Polidori, Andrea; Pikelnaya, Olga; Price, Eric; Sachs, Torsten; Serafimovich, Andrei; Zondlo, Mark; Zulueta, Rommel

    2016-04-01

    Methane plays a critical role in the radiation balance, chemistry of the atmosphere, and air quality. The major sources of methane include agricultural and natural production, landfill emissions, oil and gas development sites, and natural gas distribution networks in rural and urban environments. The majority of agricultural and natural methane production occurs in areas with little infrastructure or easily available grid power (e.g., rice fields, arctic and boreal wetlands, tropical mangroves, etc.) Past approaches for direct measurements of methane fluxes relied on fast closed-path analyzers, which typically require powerful pumps and grid power. Power and labor demands may be among the key reasons why such methane fluxes were often measured at locations with good infrastructure and grid power, and not necessarily with high methane production. Landfill methane emissions were traditionally assessed via point-in-time measurements taken at monthly or longer time intervals using techniques such as the trace plume method, the mass balance method, etc. These are subject to large uncertainties because of the snapshot nature of the measurements, while the changes in emission rates are continuous due to ongoing landfill development, changes in management practices, and the barometric pumping phenomenon. Installing a continuously operating flux station in the middle of an active landfill requires a low-power approach with no cables stretching across the landfill. The majority of oil and gas and urban methane emission happens via variable-rate point sources or diffused spots in topographically challenging terrains, such as street tunnels, elevated locations at water treatment plants, vents, etc. Locating and measuring methane emissions from such sources is challenging when using traditional micrometeorological techniques, and requires development of novel approaches. In 2010, a new lightweight high-speed high-resolution open-path technology was developed with the goal of

  14. Final Scientific/Technical Report. A closed path methane and water vapor gas analyzer

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Liukang [LI-COR Inc., Lincoln, NE (United States); McDermitt, Dayle [LI-COR Inc., Lincoln, NE (United States); Anderson, Tyler [LI-COR Inc., Lincoln, NE (United States); Riensche, Brad [LI-COR Inc., Lincoln, NE (United States); Komissarov, Anatoly [LI-COR Inc., Lincoln, NE (United States); Howe, Julie [LI-COR Inc., Lincoln, NE (United States)

    2012-02-01

    Robust, economical, low-power and reliable closed-path methane (CH4), carbon dioxide (CO2), and water vapor (H2O) analyzers suitable for long-term measurements are not readily available commercially. Such analyzers are essential for quantifying the amount of CH4 and CO2 released from various ecosystems (wetlands, rice paddies, forests, etc.) and other surface contexts (e.g. landfills, animal husbandry lots, etc.), and for understanding the dynamics of the atmospheric CH4 and CO2 budget and their impact on climate change and global warming. The purpose of this project is to develop a closed-path methane, carbon dioxide gas and water vapor analyzer capable of long-term measurements in remote areas for global climate change and environmental research. The analyzer will be capable of being deployed over a wide range of ecosystems to understand methane and carbon dioxide exchange between the atmosphere and the surface. Measurements of methane and carbon dioxide exchange need to be made all year-round with limited maintenance requirements. During this Phase II effort, we successfully completed the design of the electronics, optical bench, trace gas detection method and mechanical infrastructure. We are using the technologies of two vertical cavity surface emitting lasers, a multiple-pass Herriott optical cell, wavelength modulation spectroscopy and direct absorption to measure methane, carbon dioxide, and water vapor. We also have designed the instrument application software, Field Programmable Gate Array (FPGA), along with partial completion of the embedded software. The optical bench has been tested in a lab setting with very good results. Major sources of optical noise have been identified and through design, the optical noise floor is approaching -60dB. Both laser modules can be temperature controlled to help maximize the stability of the analyzer. Additionally, a piezo electric transducer has been

  15. Mineral and organic compounds in leachate from landfill with concentrate recirculation.

    Science.gov (United States)

    Talalaj, Izabela Anna

    2015-02-01

    The effect of a reverse osmosis concentrate recirculation on the mineral and organic compounds in a landfill leachate was investigated. Investigated was the quality of a leachate from two landfills operated for different periods (a 20-year-old Cell A and a 1-year-old Cell B), where the concentrate was recirculated. Examined were general parameters (conductivity, pH), organic compounds (biochemical oxygen demand (BOD), chemical oxygen demand (COD), total organic nitrogen, BOD/COD), and inorganic compounds (nitrogen ammonia, sulfite, sulfate, cyanide, boron, chloride, ferrous, zinc, chrome, copper). The findings from the first year of investigation showed that over the initial period of recirculation, the concentration of organic compounds (BOD, COD) increased, but after 6 months their values stabilized. It indicates that the concentrate recirculation accelerated organic decomposition, especially in the new landfill Cell. The analysis of inorganic parameters showed that recirculation landfills produce a leachate with a higher concentration of N-NH4, and Cl(-). In case of the old landfill Cell, an increase in B and Fe was also noticeable. These compounds are cyclically washed out from a waste dump and require an additional pretreatment in order to exclude them from recirculation cycle. The increased concentration of Cu, Zn, and Fe was noticed during the initial months of recirculation and in the season of intense atmospheric precipitation in the leachate from both Cells. Higher values of electro conductivity, Cl(-), N-NH4 (+), B, and Fe in the leachate from the old field indicate that the attenuation capacity of this landfill is close to exhaustion.

  16. Internal short circuit and accelerated rate calorimetry tests of lithium-ion cells: Considerations for methane-air intrinsic safety and explosion proof/flameproof protection methods.

    Science.gov (United States)

    Dubaniewicz, Thomas H; DuCarme, Joseph P

    2016-09-01

    Researchers with the National Institute for Occupational Safety and Health (NIOSH) studied the potential for lithium-ion cell thermal runaway from an internal short circuit in equipment for use in underground coal mines. In this third phase of the study, researchers compared plastic wedge crush-induced internal short circuit tests of selected lithium-ion cells within methane (CH4)-air mixtures with accelerated rate calorimetry tests of similar cells. Plastic wedge crush test results with metal oxide lithium-ion cells extracted from intrinsically safe evaluated equipment were mixed, with one cell model igniting the chamber atmosphere while another cell model did not. The two cells models exhibited different internal short circuit behaviors. A lithium iron phosphate (LiFePO4) cell model was tolerant to crush-induced internal short circuits within CH4-air, tested under manufacturer recommended charging conditions. Accelerating rate calorimetry tests with similar cells within a nitrogen purged 353-mL chamber produced ignitions that exceeded explosion proof and flameproof enclosure minimum internal pressure design criteria. Ignition pressures within a 20-L chamber with 6.5% CH4-air were relatively low, with much larger head space volume and less adiabatic test conditions. The literature indicates that sizeable lithium thionyl chloride (LiSOCl2) primary (non rechargeable) cell ignitions can be especially violent and toxic. Because ignition of an explosive atmosphere is expected within explosion proof or flameproof enclosures, there is a need to consider the potential for an internal explosive atmosphere ignition in combination with a lithium or lithium-ion battery thermal runaway process, and the resulting effects on the enclosure.

  17. FULL SCALE BIOREACTOR LANDFILL FOR CARBON SEQUESTRATION AND GREENHOUSE EMISSION CONTROL

    Energy Technology Data Exchange (ETDEWEB)

    Ramin Yazdani; Jeff Kieffer; Heather Akau

    2003-12-01

    The Yolo County Department of Planning and Public Works is constructing a full-scale bioreactor landfill as a part of the Environmental Protection Agency's (EPA) Project XL program to develop innovative approaches for carbon sequestration and greenhouse emission control. The overall objective is to manage landfill solid waste for rapid waste decomposition and maximum landfill gas generation and capture for carbon sequestration and greenhouse emission control. Waste decomposition is accelerated by improving conditions for either the aerobic or anaerobic biological processes and involves circulating controlled quantities of liquid (leachate, groundwater, gray water, etc.), and, in the aerobic process, large volumes of air. The first phase of the project entails the construction of a 12-acre module that contains a 6-acre anaerobic cell, a 3.5-acre anaerobic cell, and a 2.5-acre aerobic cell at the Yolo County Central Landfill near Davis, California. The cells are highly instrumented to monitor bioreactor performance. Liquid addition has commenced in the 3.5-acre anaerobic cell and the 6-acre anaerobic cell. Construction of the 2.5-acre aerobic cell and biofilter has been completed. The remaining task to be completed is to test the biofilter prior to operation, which is currently anticipated to begin in January 2004. The current project status and preliminary monitoring results are summarized in this report.

  18. Full Scale Bioreactor Landfill for Carbon Sequestration and Greenhouse Emission Control

    Energy Technology Data Exchange (ETDEWEB)

    Ramin Yazdani; Jeff Kieffer; Kathy Sananikone; Don Augenstein

    2005-03-30

    The Yolo County Department of Planning and Public Works constructed a full-scale bioreactor landfill as a part of the Environmental Protection Agency's (EPA) Project XL program to develop innovative approaches for carbon sequestration and greenhouse emission control. The overall objective was to manage landfill solid waste for rapid waste decomposition and maximum landfill gas generation and capture for carbon sequestration and greenhouse emission control. Waste decomposition is accelerated by improving conditions for either the aerobic or anaerobic biological processes and involves circulating controlled quantities of liquid (leachate, groundwater, gray water, etc.), and, in the aerobic process, large volumes of air. The first phase of the project entailed the construction of a 12-acre module that contained a 6-acre anaerobic cell, a 3.5-acre anaerobic cell, and a 2.5-acre aerobic cell at the Yolo County Central Landfill near Davis, California. The cells were highly instrumented to monitor bioreactor performance. Liquid addition commenced in the 3.5-acre anaerobic cell and the 6-acre anaerobic cell. Construction of the 2.5-acre aerobic cell and biofilter has been completed. The current project status and preliminary monitoring results are summarized in this report.

  19. Kinetics of Internal Methane Steam Reforming in Solid Oxide Fuel Cells and Its Influence on Cell Performance– Coupling Experiments and Modeling

    NARCIS (Netherlands)

    Fan, L.; Pourquie, M.J.B.M.; Thattai, A.; Verkooijen, A.H.M.; Aravind, P.V.

    2013-01-01

    Mathematical modeling tools are useful for predicting the safe operation limits and efficiencies of SOFCs. For a particular SOFC design, variations in internal methane reforming kinetic parameters is expected to affect local gas compositions, local Nernst voltages, current densities and temperature

  20. Electrochemical evaluation of sulfur poisoning in a methane-fuelled solid oxide fuel cell: Effect of current density and sulfur concentration

    DEFF Research Database (Denmark)

    Hagen, Anke; Johnson, Gregory B.; Hjalmarsson, Per

    2014-01-01

    A Ni/ScYSZ based SOFC was tested at 1, 0.5, 0.25, and 0 (OCV) A cm−2 in methane fuel containing 0–100 ppm H2S. Analysis of cell voltage loss during short-term H2S poisoning showed that SOFC performance loss was generally larger at higher current loads. Separating the effect of H2S on catalytic...... by the presence of H2S in the fuel; the lower frequency mass transfer/fuel reforming processes and higher frequency charge transfer/triple phase boundary (TPB) processes. At high current densities (0.5 and 1 A cm−2), mass transfer/fuel reforming processes were the most sensitive to sulfur poisoning. At OCV...... in the anode, leading to less available fuel and a higher fuel utilization. All poisoning effects were reversible after removing H2S from the fuel....

  1. Electrochemical treatment of leachates from sanitary landfills

    Directory of Open Access Journals (Sweden)

    ANNABEL FERNANDES

    2013-06-01

    Full Text Available The electrochemical treatment of leachate samples from a Portuguese intermunicipal sanitary landfill was carried out using anodic oxidation. The treatment was performed in a pilot plant that possesses an electrochemical cell, with boron-doped diamond electrodes, working in batch mode with recirculation. The influence of the applied current density and the flow rate on the performance of the electrochemical oxidation was investigated. Current density was decreased by steps, during the degradation, in order to study this effect on the efficiency of the process. For the assays run at equal flow rate and initial current intensity, chemical oxygen demand (COD removal seems to depend mainly on the charge passed and the variation of the current density during the anodic oxidation process can reduce the energetic costs. An increase in the recirculation flow rate leads to an increase in the organic load removal rate and a consequent decrease in the energetic costs, but it decreases the nitrogen removal rate. Also, the bias between dissolved organic carbon and COD removals increases with flow rate, indicating that an increase in recirculation flow rate decreases the mineralization index.

  2. Best Practices for Siting Solar Photovoltaics on Municipal Solid Waste Landfills. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Kiatreungwattana, K.; Mosey, G.; Jones-Johnson, S.; Dufficy, C.; Bourg, J.; Conroy, A.; Keenan, M.; Michaud, W.; Brown, K.

    2013-04-01

    The Environmental Protection Agency and the National Renewable Energy Laboratory developed this best practices document to address common technical challenges for siting solar photovoltaics (PV) on municipal solid waste (MSW) landfills. The purpose of this document is to promote the use of MSW landfills for solar energy systems. Closed landfills and portions of active landfills with closed cells represent thousands of acres of property that may be suitable for siting solar photovoltaics (PV). These closed landfills may be suitable for near-term construction, making these sites strong candidate to take advantage of the 30% Federal Business Energy Investment Tax Credit. It was prepared in response to the increasing interest in siting renewable energy on landfills from solar developers; landfill owners; and federal, state, and local governments. It contains examples of solar PV projects on landfills and technical considerations and best practices that were gathered from examining the implementation of several of these projects.

  3. Photovoltaics on Landfills in Puerto Rico

    Energy Technology Data Exchange (ETDEWEB)

    Salasovich, J.; Mosey, G.

    2011-01-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Commonwealth of Puerto Rico for a feasibility study of m0treAlables on several brownfield sites. The EPA defines a brownfield as 'a property, the expansion, redevelopment, or reuse of which may be complicated by the presence or potential presence of a hazardous substance, pollutant, or contaminant.' All of the brownfields in this study are landfill sites. Citizens of Puerto Rico, city planners, and site managers are interested in redevelopment uses for landfills in Puerto Rico, which are particularly well suited for solar photovoltaic (PV) installation. The purpose of this report is to assess the landfills with the highest potential for possible solar PV installation and estimate cost, performance, and site impacts of three different PV options: crystalline silicon (fixed-tilt), crystalline silicon (single-axis tracking), and thin film (fixed-tilt). Each option represents a standalone system that can be sized to use an entire available site area. In addition, the report outlines financing options that could assist in the implementation of a system. The feasibility of PV systems installed on landfills is highly impacted by the available area for an array, solar resource, operating status, landfill cap status, distance to transmission lines, and distance to major roads. All of the landfills in Puerto Rico were screened according to these criteria in order to determine the sites with the greatest potential. Eight landfills were chosen for site visits based on the screening criteria and location. Because of time constraints and the fact that Puerto Rico is a relatively large island, the eight landfills for this visit were all located in the eastern half of the island. The findings from this report can be applied to landfills in the western half of the island. The economics of a potential PV system on landfills in Puerto Rico depend

  4. [Isolation of a methane-utilizing bacterium and its application in measuring methane gas].

    Science.gov (United States)

    Zhao, Gengui; Zheng, Jun; Wen, Guangming; Yang, Suping; Dong, Chuan

    2008-03-01

    A bacterial strain ME16 was isolated from Jinyang Lake in Taiyuan of Shanxi Province, China. Gas chromatography analysis showed that the strain could use methane as the sole carbon and energy source. Based on 16S rDNA sequence analysis, the strain was identified as Pseudomonas aeruginosa. Effects of inoculum size, temperature, methane content and initial pH of media on cell growth were studied. In addition, we examined the response time of methane gas to dissolved oxygen and the relationship between consumption of dissolved oxygen and different methane gas content with PVA-H3BO3 immobilized cell of ME16 using electrochemical method. The optimal conditions for cell growth were 2% inoculum size, 25% methane content, 30 degrees C and pH 6.0. Response time was within 100 s after adding of immobilized cells to reaction system. The linear range of measured methane content was from 0 to 16%, with the correlation coefficient 0.9954. Hence, this strain has potential application in developing of methane biosensor.

  5. Landfills as critical infrastructures: analysis of observational datasets after 12 years of non-invasive monitoring

    Science.gov (United States)

    Scozzari, Andrea; Raco, Brunella; Battaglini, Raffaele

    2016-04-01

    This work presents the results of more than ten years of observations, performed on a regular basis, on a municipal solid waste disposal located in Italy. Observational data are generated by the combination of non-invasive techniques, involving the direct measurement of biogas release to the atmosphere and thermal infrared imaging. In fact, part of the generated biogas tends to escape from the landfill surface even when collecting systems are installed and properly working. Thus, methodologies for estimating the behaviour of a landfill system by means of direct and/or indirect measurement systems have been developed in the last decades. It is nowadays known that these infrastructures produce more than 20% of the total anthropogenic methane released to the atmosphere, justifying the need for a systematic and efficient monitoring of such infrastructures. During the last 12 years, observational data regarding a solid waste disposal site located in Tuscany (Italy) have been collected on a regular basis. The collected datasets consist in direct measurements of gas flux with the accumulation chamber method, combined with the detection of thermal anomalies by infrared radiometry. This work discusses the evolution of the estimated performance of the landfill system, its trends, the benefits and the critical aspects of such relatively long-term monitoring activity.

  6. Structure and function of methanotrophic communities in a landfill-cover soil.

    Science.gov (United States)

    Henneberger, Ruth; Lüke, Claudia; Mosberger, Lona; Schroth, Martin H

    2012-07-01

    In landfill-cover soils, aerobic methane-oxidizing bacteria (MOB) convert CH(4) to CO(2), mitigating emissions of the greenhouse gas CH(4) to the atmosphere. We investigated overall MOB community structure and assessed spatial differences in MOB diversity, abundance and activity in a Swiss landfill-cover soil. Molecular cloning, terminal restriction-fragment length polymorphism (T-RFLP) and quantitative PCR of pmoA genes were applied to soil collected from 16 locations at three different depths to study MOB community structure, diversity and abundance; MOB activity was measured in the field using gas push-pull tests. The MOB community was highly diverse but dominated by Type Ia MOB, with novel pmoA sequences present. Type II MOB were detected mainly in deeper soil with lower nutrient and higher CH(4) concentrations. Substantial differences in MOB community structure were observed between one high- and one low-activity location. MOB abundance was highly variable across the site [4.0 × 10(4) to 1.1 × 10(7) (g soil dry weight)(-1)]. Potential CH(4) oxidation rates were high [1.8-58.2 mmol CH(4) (L soil air)(-1) day(-1) ] but showed significant lateral variation and were positively correlated with mean CH(4) concentrations (P structure are driving factors in CH(4) oxidation at this landfill.

  7. Predicted growth of world urban food waste and methane production.

    Science.gov (United States)

    Adhikari, Bijaya K; Barrington, Suzelle; Martinez, José

    2006-10-01

    Landfill gas emissions are one of the largest anthropogenic sources of methane especially because of food waste (FW). To prevent these emissions growing with world population, future FW best management practices need to be evaluated. The objective of this paper was therefore to predict FW production for 2025 if present management practices are maintained, and then, to compare the impact of scenario 1: encouraging people to stay in rural areas and composting 75% of their FW, and; of scenario 2, where in addition to scenario 1, composting or anaerobically digesting 75% of urban FW (UFW). A relationship was established between per capita gross domestic product (GDP) and the population percentage living in urban areas (%UP), as well as production of municipal solid waste (MSW) and UFW. With estimated GDP and population growth per country, %UP and production of MSW and UFW could be predicted for 2025. A relatively accurate (R(2) > 0.85) correlation was found between GDP and %UP, and between GDP and mass of MSW and FW produced. On a global scale, MSW and UFW productions were predicted to increase by 51 and 44%, respectively, from 2005 to 2025. During the same period, and because of its expected economic development, Asia was predicted to experience the largest increase in UFW production, of 278 to 416 Gkg. If present MSW management trends are maintained, landfilled UFW was predicted to increase world CH4 emissions from 34 to 48 Gkg and the landfill share of global anthropogenic emissions from 8 to 10%. In comparison with maintaining present FW management practices, scenario 1 can lower UFW production by 30% and maintain the landfill share of the global anthropogenic emissions at 8%. With scenario 2, the landfill share of global anthropogenic emissions could be further reduced from 8 to 6% and leachate production could be reduced by 40%.

  8. CO-DIGESTION OF SEWAGE SLUDGE AND MATURE LANDFILL LEACHATE IN PRE-BIOAUGMENTED SYSTEM

    Directory of Open Access Journals (Sweden)

    Agnieszka Montusiewicz

    2014-10-01

    Full Text Available The study examined the effects of co-digestion of sewage sludge and mature landfill leachate at the volumetric ratio of 95:5% in primarily bioaugmented system. Bioaugmentation was carried out with the use of commercial product Arkea® in the volumetric dose of 5% and lasted three months prior to the co-digestion start-up. Co-digestion was undergone without bioaugmentation. The results indicated that in the first period (of three months following bioaugmentation, co-digestion led to biogas/methane yields only 5-8% lower as compared to anaerobic digestion of sewage sludge, and the differences were not statistically significant. Moreover, a comparable value of volatile solids removal was obtained. However, the effects became worse over time, i.e. a lower organics removal efficiency of 16% as well as 9.5–13% decreases of biogas/methane yields were achieved by applying co-digestion for a further period (of the same duration. Co-digestion of sewage sludge and mature landfill leachate could be recognized as quite efficient in the system that was primarily bioaugmented with the use of Arkea®. However, the beneficial impact of bioaugmentation remained for the limited period of three months after its completion. To sustain the favourable effects a periodical, repeatable bioaugmentation of the co-digestion system is required.

  9. Inhibitory effects of sulfur compounds on methane oxidation by a methane-oxidizing consortium.

    Science.gov (United States)

    Lee, Eun-Hee; Moon, Kyung-Eun; Kim, Tae Gwan; Lee, Sang-Don; Cho, Kyung-Suk

    2015-12-01

    Kinetic and enzymatic inhibition experiments were performed to investigate the effects of methanethiol (MT) and hydrogen sulfide (H2S) on methane oxidation by a methane-oxidizing consortium. In the coexistence of MT and H2S, the oxidation of methane was delayed until MT and H2S were completely degraded. MT and H2S could be degraded, both with and without methane. The kinetic analysis revealed that the methane-oxidizing consortium showed a maximum methane oxidation rate (Vmax) of 3.7 mmol g-dry cell weight (DCW)(-1) h(-1) and a saturation constant (Km) of 184.1 μM. MT and H2S show competitive inhibition on methane oxidation, with inhibition values (Ki) of 1504.8 and 359.8 μM, respectively. MT was primary removed by particulate methane monooxygenases (pMMO) of the consortium, while H2S was degraded by the other microorganisms or enzymes in the consortium. DNA and mRNA transcript levels of the pmoA gene expressions were decreased to ∼10(6) and 10(3)pmoA gene copy number g-DCW(-1) after MT and H2S degradation, respectively; however, both the amount of the DNA and mRNA transcript recovered their initial levels of ∼10(7) and 10(5)pmoA gene copy number g-DCW(-1) after methane oxidation, respectively. The gene expression results indicate that the pmoA gene could be rapidly reproducible after methane oxidation. This study provides comprehensive information of kinetic interactions between methane and sulfur compounds.

  10. Estimate the potential production of electricity: a case study of the sanitary landfill of Santo Andre, Sao Paulo, Brazil; Estimativa do potencial de producao de eletricidade: estudo de caso do aterro sanitario de Santo Andre, Sao Paulo, Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Elissando Rocha da; Moreira, Joao M. L.; Candiani, Giovano [Instituto Federal de Educacao, Ciencia e Tecnologia de Sao Paulo (IFSP), SP (Brazil)

    2010-07-01

    The recovery of the biogas generated from sanitary landfills, associated to its energetic use has been widely discussed. Thus, this paper aims to estimate the potential production of electric energy from sanitary landfill Santo Andre-SP. The biogas production was estimated using the rate of deposition of solid wastes in the landfill, using some mathematical models with parameters suggested by two models: LanGEM-USEPA (conventional landfill) and Word Bank. These results indicate that the potential of biogas production will be approximately 11 x 10{sup 6} Kg of methane/year in 2017 and production of electric energy in that year will be approximately 32,000 MWh, considering an of 75% over collection of biogas. (author)

  11. Spatial patterns and source attribution of urban methane in the Los Angeles Basin

    Science.gov (United States)

    Hopkins, Francesca M.; Kort, Eric A.; Bush, Susan E.; Ehleringer, James R.; Lai, Chun-Ta; Blake, Donald R.; Randerson, James T.

    2016-03-01

    Urban areas are increasingly recognized as a globally important source of methane to the atmosphere; however, the location of methane sources and relative contributions of source sectors are not well known. Recent atmospheric measurements in Los Angeles, California, USA, show that more than a third of the city's methane emissions are unaccounted for in inventories and suggest that fugitive fossil emissions are the unknown source. We made on-road measurements to quantify fine-scale structure of methane and a suite of complementary trace gases across the Los Angeles Basin in June 2013. Enhanced methane levels were observed across the basin but were unevenly distributed in space. We identified 213 methane hot spots from unknown emission sources. We made direct measurements of ethane to methane (C2H6/CH4) ratios of known methane emission sources in the region, including cattle, geologic seeps, landfills, and compressed natural gas fueling stations, and used these ratios to determine the contribution of biogenic and fossil methane sources to unknown hot spots and to local urban background air. We found that 75% of hot spots were of fossil origin, 20% were biogenic, and 5% of indeterminate source. In regionally integrated air, we observed a wider range of C2H6/CH4 values than observed previously. Fossil fuel sources accounted for 58-65% of methane emissions, with the range depending on the assumed C2H6/CH4 ratio of source end-members and model structure. These surveys demonstrated the prevalence of fugitive methane emissions across the Los Angeles urban landscape and suggested that uninventoried methane sources were widely distributed and primarily of fossil origin.

  12. Evaluation of the Treatment Process of Landfill Leachate Using the Toxicity Assessment Method

    Directory of Open Access Journals (Sweden)

    Aifeng Qiu

    2016-12-01

    Full Text Available Landfill leachate is composed of a complex composition with strong biological toxicity. The combined treatment process of coagulation and sedimentation, anaerobics, electrolysis, and aerobics was set up to treat landfill leachate. This paper explores the effect of different operational parameters of coagulation and sedimentation tanks and electrolytic cells, while investigating the combined process for the removal efficiency of physicochemical indices after processing the landfill leachate. Meanwhile, a battery of toxicity tests with Vibrio fischeri, zebrafish larvae, and embryos were conducted to evaluate acute toxicity and calculated the toxicity reduction efficiency after each treatment process. The combined treatment process resulted in a 100% removal efficiency of Cu, Cd and Zn, and a 93.50% and an 87.44% removal efficiency of Ni and Cr, respectively. The overall removal efficiency of chemical oxygen demand (COD, ammonium nitrogen (NH4+-N, and total nitrogen (TN were 93.57%, 97.46% and 73.60%, respectively. In addition, toxicity test results showed that the acute toxicity of landfill leachate had also been reduced significantly: toxicity units (TU decreased from 84.75 to 12.00 for zebrafish larvae, from 82.64 to 10.55 for zebrafish embryos, and from 3.41 to 0.63 for Vibrio fischeri. The combined treatment process was proved to be an efficient treatment method to remove heavy metals, COD, NH4+-N, and acute bio-toxicity of landfill leachate.

  13. Reduction of greenhouse gases emissions listed in the Kyoto Protocol by the utilization of landfill gas using solid oxide fuel cells; Reducao das emissoes de gases de efeito estufa listados no protocolo de Quioto pelo aproveitamento do gas gerado em aterros sanitarios utilizando celulas a combustivel de oxido solido. Estudo de caso do aterro municipal de Santo Andre, SP, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Paris, Alexandre Gellert

    2007-07-01

    In the last few years, the Kyoto Protocol had been a subject very debated, at first, in a restricted niche, manly academics and professionals related to the area of climate changes. On 16th February 2005 the Kyoto Protocol entered into force and with this a lot of publicity all over the world, so today is common to hear about it at the mass communications media. The extension of the subject is broad, this work discuss the utilization of one the Kyoto's flexibility mechanisms, to contribute to financing the use of the landfill gas in the solid oxide fuel cells. Among the three mechanisms presented in the Kyoto Protocol, the clean development mechanism (CDM) in article 12, is the only one that can be implemented by non-Annex I countries, the case of Brazil. In other hand, the issue of solid waste in Brazil is critical. Even being illegal, most of the solid waste goes to uncontrolled areas in open air places 'lixoes', causing degradation of the environment and the communities around this areas, and also emission of green house gases (GHG), deregulating the global climate system. Decontaminate this areas and the construction of landfills to replace than, considering the landfill as a bioreactor, and the utilization of the biogas to generate power can improve nowadays picture that we are facing. The utilization of an innovative alternative technology as the solid oxide fuel cell (SOFC) instead the conventional technologies will be more efficient and environmentally better. Among other barriers the cost is pointed as the biggest. In this context, the SOFC is the most expensive fuel cell, so the utilization of CDM can contribute to finance the application of this technology. Scenarios were made of 250 kW, 500 kW, 1,000 kW, 5,000 kW and 10,000 kW of installed power using biogas from the Municipal Landfill of Santo Andre. The calculations of the emission factor were done ex ante and ex post according to ACM0002. Comparing the costs of the installed power

  14. Ni-(Ce0.8-xTix)Sm0.2O2-δ anode for low temperature solid oxide fuel cells running on dry methane fuel

    Science.gov (United States)

    Han, Bing; Zhao, Kai; Hou, Xiaoxue; Kim, Dong-Jin; Kim, Bok-Hee; Ha, Su; Norton, M. Grant; Xu, Qing; Ahn, Byung-Guk

    2017-01-01

    A titanium-doped Ce0.8Sm0.2O1.9 composite is developed as an anode component of low temperature solid oxide fuel cells running on methane fuel. Crystallographic parameters of (Ce0.8-xTix)Sm0.2O2-δ (0.00 cell consisting of Ni-(Ce0.8-xTix)Sm0.2O2-δ anode/Ce0.8Sm0.2O1.9 electrolyte/La0.6Sr0.4Co0.2Fe0.8O3-δ cathode. Catalytic properties of Ni-(Ce0.8-xTix)Sm0.2O2-δ are inspected with the electrochemical performance and performance stability of the cells in dry methane fuel. The cell with Ni-(Ce0.73Ti0.07)Sm0.2O2-δ (x = 0.07) anode displays a low polarization resistance and an optimum maximum power density (679 mW cm-2 at 600 °C). A performance stability investigation indicates that the cell exhibits a fairly low degradation rate of 3 mV h-1 during a 31 h operation in dry methane. These findings suggest the application potential of the titanium doped Ce0.8Sm0.2O1.9 for the anode of solid oxide fuel cells.

  15. Adsorption and transport of methane in biochars derived from waste wood.

    Science.gov (United States)

    Sadasivam, Bala Yamini; Reddy, Krishna R

    2015-09-01

    Mitigation of landfill gas (LFG) is among the critical aspects considered in the design of a landfill cover in order to prevent atmospheric pollution and control global warming. In general, landfill cover soils can partially remove methane (CH4) through microbial oxidation carried out by methanotrophic bacteria present within them. The oxidizing capacity of these landfill cover soils may be improved by adding organic materials, such as biochar, which increase adsorption and promote subsequent or simultaneous oxidation of CH4. In this study, seven wood-derived biochars and granular activated carbon (GAC) were characterized for their CH4 adsorption capacity by conducting batch and small-scale column studies. The effects of influential factors, such as exposed CH4 concentration, moisture content and temperature on CH4 adsorption onto biochars, were determined. The CH4 transport was modeled using a 1-D advection-dispersion equation that accounted for sorption. The effects of LFG inflow rates and moisture content on the combined adsorption and transport properties of biochars were determined. The maximum CH4 adsorption capacity of GAC (3.21mol/kg) was significantly higher than that of the biochars (0.05-0.9mol/kg). The CH4 gas dispersion coefficients for all of the biochars ranged from 1×10(-3) to 3×10(-3)m(2)s(-1). The presence of moisture significantly suppressed the extent of methane adsorption onto the biochars and caused the methane to break through within shorter periods of time. Overall, certain biochar types have a high potential to enhance CH4 adsorption and transport properties when used as a cover material in landfills. However, field-scale studies need to be conducted in order to evaluate the performance of biochar-based cover system under a more dynamic field condition that captures the effect of seasonal and temporal changes.

  16. Feasibility analysis of remedial scheme of Qilongcun landfill

    Institute of Scientific and Technical Information of China (English)

    LUO Yun-ju; LIU Dong-yan; LIU Xin-rong; LI Xiu-lan

    2006-01-01

    Based on hydro-geological of Qilongcun landfill, the transportation mathematical model of leachat was established. The boundaries conditions and replenishment of model were determined. The leachate COD density and the water level were simulated, and the model was identified, and then the right model was defined. The right model was used to simulate leachate COD density in the interior, exterior, and peripheral of landfill. The results show that the COD densities are not high. The pollution is slight in the interior of landfill and is little in the exterior of landfill. They are proving the overburden on top of landfill and drain around the landfill is right. The max. density on the south of landfill shows it is scientific that the cisterns are building on the south of landfill. The paper shows the remediation scheme is feasible.

  17. MOLECULAR AND CULTURAL METHODOLOGIES FOR ENUMERATING BACTERIA IN LANDFILL LEACHATES

    Science.gov (United States)

    Landfill bioreactor technology has been under investigation in the field for its potential economic and waste treatment benefits over conventional landfill systems. A better understanding of biological influences on the stabilization process is needed for incorporation into the e...

  18. Nitrogen Removal from Landfill Leachate by Microalgae

    Directory of Open Access Journals (Sweden)

    Sérgio F. L. Pereira

    2016-11-01

    Full Text Available Landfill leachates result from the degradation of solid residues in sanitary landfills, thus presenting a high variability in terms of composition. Normally, these effluents are characterized by high ammoniacal-nitrogen (N–NH4+ concentrations, high chemical oxygen demands and low phosphorus concentrations. The development of effective treatment strategies becomes difficult, posing a serious problem to the environment. Phycoremediation appears to be a suitable alternative for the treatment of landfill leachates. In this study, the potential of Chlorella vulgaris for biomass production and nutrients (mainly nitrogen and phosphorus removal from different compositions of a landfill leachate was evaluated. Since microalgae also require phosphorus for their growth, different loads of this nutrient were evaluated, giving the following N:P ratios: 12:1, 23:1 and 35:1. The results have shown that C. vulgaris was able to grow in the different leachate compositions assessed. However, microalgal growth was higher in the cultures presenting the lowest N–NH4+ concentration. In terms of nutrients uptake, an effective removal of N–NH4+ and phosphorus was observed in all the experiments, especially in those supplied with phosphorus. Nevertheless, N–NO3− removal was considered almost negligible. These promising results constitute important findings in the development of a bioremediation technology for the treatment of landfill leachates.

  19. Nitrogen Removal from Landfill Leachate by Microalgae

    Science.gov (United States)

    Pereira, Sérgio F. L.; Gonçalves, Ana L.; Moreira, Francisca C.; Silva, Tânia F. C. V.; Vilar, Vítor J. P.; Pires, José C. M.

    2016-01-01

    Landfill leachates result from the degradation of solid residues in sanitary landfills, thus presenting a high variability in terms of composition. Normally, these effluents are characterized by high ammoniacal-nitrogen (N–NH4+) concentrations, high chemical oxygen demands and low phosphorus concentrations. The development of effective treatment strategies becomes difficult, posing a serious problem to the environment. Phycoremediation appears to be a suitable alternative for the treatment of landfill leachates. In this study, the potential of Chlorella vulgaris for biomass production and nutrients (mainly nitrogen and phosphorus) removal from different compositions of a landfill leachate was evaluated. Since microalgae also require phosphorus for their growth, different loads of this nutrient were evaluated, giving the following N:P ratios: 12:1, 23:1 and 35:1. The results have shown that C. vulgaris was able to grow in the different leachate compositions assessed. However, microalgal growth was higher in the cultures presenting the lowest N–NH4+ concentration. In terms of nutrients uptake, an effective removal of N–NH4+ and phosphorus was observed in all the experiments, especially in those supplied with phosphorus. Nevertheless, N–NO3− removal was considered almost negligible. These promising results constitute important findings in the development of a bioremediation technology for the treatment of landfill leachates. PMID:27869676

  20. Isotopic constraints on sources of methane in Los Angeles, California, USA (Invited)

    Science.gov (United States)

    Townsend-Small, A.; Tyler, S. C.; Christensen, L.; Xu, X.; Pataki, D. E.

    2009-12-01

    Methane is a powerful greenhouse gas and an important contributor to global warming. Recent studies have suggested that methane emissions in large cities are underestimated with several models even indicating that substantial emissions attributed to cities are in part from regional and/or encroaching agricultural sources rather than from urban fossil fuel sources. We have found that stable isotopes (13-C and D) and radiocarbon (C-14) are excellent tracers of various sources of methane in Los Angeles, California. Measurements of the d13C and dD of methane from discrete sources show excellent separation between urban sources, such as vehicle emissions, power plants, oil refineries, landfills, and sewage treatment plants and agricultural sources like cows, biogas, and cattle feedlots. In addition, radiocarbon is an excellent tracer of modern versus fossil fuel contributions to methane emissions in the region. Preliminary measurements of background air in Los Angeles indicate that the major source of excess methane is vehicle emissions with most additional CH4 likely contributed from among other fossil fuel sources such as oil refining or power plants. We are currently confirming these results with broader field campaigns and additional measurements, including continuous measurements of atmospheric methane concentration using tunable laser spectroscopy. The combination of high-resolution tunable laser concentration measurements and precise isotope measurements using mass spectrometry is a very promising and powerful tool for methane source monitoring.

  1. Assessment of microbiological and chemical properties in a municipal landfill area.

    Science.gov (United States)

    Frączek, Krzysztof J; Ropek, Dariusz R; Lenart-Boroń, Anna M

    2014-01-01

    This study aimed at determining the environmental hazards for soils posed by a large municipal landfilll. The concentrations of heavy metals and Policyclic Aromatic Hydrocarbons, as well as microbial composition (i.e., mesophilic bacteria, actinomycetes, molds, Salmonella, Staphylococcus, Clostridium perfringens) in four soils within and in the vicinity of the landfill were evaluated and compared to waste samples. Both chemical and microbiological analyses revealed only limited contamination of surrounding areas. Although the increased alkalinity of soils was detected, the concentrations of heavy metals and Polycyclic Aromatic Hydrocarbons (PAHs) did not exceed the admissible values. All examined microbial groups were abundant in soil and waste. The highest microbial cell numbers were observed in warm summer and spring months. Although the site south of the landfill shows no trace of microbial contamination, pathogenic bacteria were found north of the landfill. This may suggest that there are other, more effective, transmission routes of bacteria than groundwater flow.

  2. Sensitivity analysis of the waste composition and water content parameters on the biogas production models on solid waste landfills

    Science.gov (United States)

    Rodrigo-Ilarri, Javier; Segura-Sobrino, Francisco; Rodrigo-Clavero, Maria-Elena

    2014-05-01

    Landfills are commonly used as the final deposit of urban solid waste. Despite the waste is previously processed on a treatment plant, the final amount of organic matter which reaches the landfill is large however. The biodegradation of this organic matter forms a mixture of greenhouse gases (essentially Methane and Carbon-Dioxide as well as Ammonia and Hydrogen Sulfide). From the environmental point of view, solid waste landfills are therefore considered to be one of the main greenhouse gas sources. Different mathematical models are usually applied to predict the amount of biogas produced on real landfills. The waste chemical composition and the availability of water in the solid waste appear to be the main parameters of these models. Results obtained when performing a sensitivity analysis over the biogas production model parameters under real conditions are shown. The importance of a proper characterizacion of the waste as well as the necessity of improving the understanding of the behaviour and development of the water on the unsaturated mass of waste are emphasized.

  3. Heavy element accumulation in Evernia prunastri lichen transplants around a municipal solid waste landfill in central Italy.

    Science.gov (United States)

    Nannoni, Francesco; Santolini, Riccardo; Protano, Giuseppe

    2015-09-01

    This paper presents the results of a biomonitoring study to evaluate the environmental impact of airborne emissions from a municipal solid waste landfill in central Italy. Concentrations of 11 heavy elements, as well as photosynthetic efficiency and cell membrane integrity were measured in Evernia prunastri lichens transplanted for 4months in 17 monitoring sites around the waste landfill. Heavy element contents were also determined in surface soils. Analytical data indicated that emissions from the landfill affected Cd, Co, Cr, Cu, Ni, Pb, Sb and Zn concentrations in lichens transplanted within the landfill and along the fallout direction. In these sites moderate to severe accumulation of these heavy elements in lichens was coupled with an increase in cell membrane damage and decrease in photosynthetic efficiency. Nevertheless, results indicated that landfill emissions had no relevant impact on lichens, as heavy element accumulation and weak stress symptoms were detected only in lichen transplants from sites close to solid waste. The appropriate management of this landfill poses a low risk of environmental contamination by heavy elements.

  4. Additive effect of Ce, Mo and K to nickel-cobalt aluminate supported solid oxide fuel cell for direct internal reforming of methane

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, Bu Ho; Park, Jungdeok; Yoon, Heechul; Kim, Hyeon Hui; Kim, Lim; Chung, Jong Shik [POSTECH, Pohang (Korea, Republic of)

    2014-01-15

    Direct internal reforming of methane (steam/carbon=0.031, 850 .deg. C) is tested using button cells of Ni-YSZ/YSZ/LSM in which the anode layer is supported either on Ni-YSZ or on Ni-CoAl{sub 2}O{sub 4}. The Ni-CoAl{sub 2}O{sub 4} supported cell shows little degradation with operating time, as a result of higher resistance against carbon deposition, whereas the Ni-YSZ supported cell deactivates quickly and suffers fracture in 50 h. Upon incorporation of additives such as K, Ce, or Mo into the Ni-CoAl{sub 2}O{sub 4} support, cells with 0.5 wt% CeO{sub 2} exhibit the best stable performance as a result of reduced coke formation. Cells with 0.5 wt% Mo exhibit the lowest performance. Although no carbon deposit is detected in the cells with K{sub 2}CO{sub 3} additives, their performance is worse than that in the CeO{sub 2} case, and, in constant-current mode, there is a sudden voltage drop to zero after a certain period of time; this time becomes shorter with increasing K content. The injection of potassium into the anode side facilitates the generation of OH{sup -} and CO{sub 3}{sup 2-} in the anode and promotes the diffusion of these ions to the cathode. Increased polarization resistance at the cathode and increased electrolyte resistance result in such a sudden failure.

  5. Removal of high concentrated ammonia nitrogen from landfill leachate by landfilled waste layer

    Institute of Scientific and Technical Information of China (English)

    GUO Hui-dong; HE Pin-jing; SHAO Li-ming; LI Guo-jian

    2004-01-01

    The landfill of municipal solid waste(MSW) could be regarded as denitrification reactor and used in ammonia nitrogen biological removal process. In this research, the process was applied to municipal solid waste(MSW) collected in Shanghai, China, which was characterized with high food waste content. The NH4+ removal efficiency in the system of SBR nitrifying reactor followed by fresh and matured landfilled waste layer in series was studied. In the nitrifying reactor, above 90% of NH4+ in leachate was oxidized to NO2- and NO3-. Then high concentrated NO2- and NO3- was removed in the way of denitrification process in fresh landfilled waste layer. At the same time, degradation of fresh landfilled waste was accelerated. Up to the day 120, 136.5 gC/(kg dry waste) and 17.9 gN/(kg dry waste) were produced from waste layer. It accounted for 50.15% and 86.89% of the total carbon and nitrogen content of preliminary fresh waste, which was 4.42 times and 5.17 times higher than that of reference column respectively. After filtering through matured landfilled waste, BOD5 concentration in leachate dropped to below 100 mg/L, which would not affect following nitrification adversely. Because the matured landfilled waste acted as a well methanogenic reactor, 23% of carbon produced accumulatively from fresh landfilled waste degradation was converted into CH4.

  6. Extension of gas utilization operation time in case of decreasing methane concentration; Verlaengerung der Betriebsdauer von Gasverwertungsanlagen bei fallenden Methankonzentrationen

    Energy Technology Data Exchange (ETDEWEB)

    Hegemann, Tim [DMT GmbH und Co. KG, Essen (Germany); Brandt, Andreas [Steag GmbH, Essen (Germany). Bereich Grubengas NRW; Minegas GmbH, Essen (Germany)

    2013-06-15

    In the Ruhr area Minegas GmbH (Minegas) currently operates gas engines on abandoned mine methane at round about 17 different locations. In the course of time the methane content decreases at some production sites, while in unison the carbon dioxide content increases. Whereas the composition of abandoned mine methane and landfill gas are slightly different, the worsening of the quality is comparable, making it harder to operate the gas engines or even prevent them from running. The minimum methane concentration in the gas-mixture needed for the combustion in the gas engines can theoretically be lowered by adding pure oxygen to the gas mixture. That way, depending on the production site and the future development, the utilization of methane can be extended for years - while using the existing gas engines and technologies. (orig.)

  7. Atmospheric distribution of methane on Mars: A model study

    Science.gov (United States)

    Viscardy, Sébastien; Daerden, Frank; Neary, Lori

    2016-10-01

    In the past decade, the detection of methane (CH4) in the atmosphere of Mars has been reported several times. These observations have strongly drawn the attention of the scientific community and triggered a renewed interest in Mars as their implications for the geochemical or biological activities are remarkable. However, given that methane is expected to have a photochemical lifetime of several centuries, the relatively fast loss rates of methane estimated from Earth-based measurements remain unexplained. Although this gave rise to objections against the validity of those observations, recent in situ measurements confirmed that methane is being occasionally released into the atmosphere from an unknown source (possibly from the ground). Additionally, ExoMars/TGO was launched to Mars in March 2016. NOMAD, one of the instruments onboard TGO, will provide the first global detailed observations of methane on Mars. It is in this context that we present a model study of the behavior of methane plumes.A general circulation model for the atmosphere of Mars is applied to simulate surface emission of methane and to investigate its vertical distribution during the first weeks after the release. Such surface emissions were suggested to explain observations of methane. Previous GCM simulations focused on the horizontal evolution of the methane, but the present study focuses on the three-dimensional dispersion of methane throughout the atmosphere after the surface release. It is found that a highly nonuniform vertical distribution, including distinct vertical layers, can appear throughout the atmosphere during the first weeks after the emission. This is explained by the global circulation patterns in the atmosphere at the time of the emission. Large Hadley cells transport the methane rapidly to other locations over the planet, and methane will be stretched out in layers along the general circulation streamlines at heights corresponding to strong zonal jets.This result changes

  8. Biological conversion of coal gas to methane

    Energy Technology Data Exchange (ETDEWEB)

    Barik, S.; Vega, J.L.; Clausen, E.C.; Gaddy, J.L.

    1988-08-01

    Biological conversion of low-Btu coal synthesis gas to higher Btu methane was demonstrated using both pure co-cultures and/or adapted-mixed anaerobic bacteria. Peptostreptococcus productus metabolized coal gas to mainly acetate and CO/sub 2/. The co-cultures containing methanogens converted these products to methane. In mixed culture studies, CH/sub 4/ and small amounts of acetate were produced. Reactor studies using stirred-tank and immobilized cell reactors exhibited excellent potential to convert CO, CO/sub 2/ and H/sub 2/ to methane at higher gas flow rates. Gas retention times ranging from 0.7 to 2 hours and high agitation were required for 90 percent CO conversion in these systems. This paper also illustrates the potential of biological methanation and demonstrates the need for good mass transfer in converting gas phase substrates. 21 refs., 1 fig., 7 tabs.

  9. Use of a New Low-Power Laser-Based Instrumentation to Measure Methane Emissions from Remote Permafrost Regions

    Science.gov (United States)

    Burba, George; Sturtevant, Cove; Peltola, Olli; Schreiber, Peter; Zulueta, Rommel; Haapanala, Sami; Mammarella, Ivan; Rinne, Janne; Vesala, Timo; McDermitt, Dayle; Oechel, Walt

    2013-04-01

    The permafrost regions store significant amount of organic materials under anaerobic conditions, leading to large methane production and accumulation in the upper layers of bedrock, soil and ice. These regions are currently undergoing dramatic change in response to warming trends, and may become a significant potential source of global methane release under a warming climate over following decades and centuries. Present measurements of methane fluxes in permafrost regions have mostly been made with static chamber techniques, and very few were done with the eddy covariance approach using closed-path analyzers. Although chambers and closed-path analyzers have advantages, both techniques have significant limitations, especially for remote or portable research in cold regions. Static chamber measurements are discrete in time and space, and particularly difficult to use over polygonal tundra with highly non-uniform micro-topography and active water layer. They also may not capture the dynamics of methane fluxes on varying time scales (hourly to annual). In addition, placement of the chamber may disturb the surface integrity causing a significant over-estimation of the measured flux. Closed-path gas analyzers for measuring methane eddy fluxes employ advanced technologies such as TDLS (Tunable Diode Laser Spectroscopy), ICOS (Integrated Cavity Output Spectroscopy), WS-CRDS (wavelength scanned cavity ring-down spectroscopy), but require high flow rates at significantly reduced optical cell pressures to provide adequate response time and sharpen absorption features. Such methods, when used with the eddy covariance technique, require a vacuum pump and a total of 400-1500 Watts of grid power for the pump, climate control, and analyzer systems. The weight of such systems often exceeds 100-200 lbs, restricting practical applicability for remote or portable field studies. As a result, spatial coverage of eddy covariance methane flux measurements in cold regions remains limited

  10. Targeted modification of organic components of municipal solid waste by short-term pre-aeration and its enhancement on anaerobic degradation in simulated landfill bioreactors.

    Science.gov (United States)

    Ni, Zhe; Liu, Jianguo; Girotto, Francesca; Cossu, Raffaello; Qi, Guangxia

    2016-09-01

    Pre-aeration is effective on regulating subsequent anaerobic degradation of municipal solid waste (MSW) with high organic fractions during landfilling. The strength of pre-aeration should be optimized to intentionally remove some easily biodegradable fractions while conserve bio-methane potential as much as possible. This study investigates the evolution of organic components in MSW during 2-14days pre-aeration process and its impacts on subsequent anaerobic degradation in simulated landfill bioreactors. Results showed that a 6-day pre-aeration enabled to develop a thermophilic stage, which significantly accelerated biodegradation of organics except lignocelluloses, with removal rates of 42.8%, 76.7% and 25.1% for proteins, carbohydrates and lipids, respectively. Particularly, ammonia from accelerated ammonification in the thermophilic stage neutralized VFAs generated from anaerobic landfilling. As a result, the MSW with 6-day pre-aeration obtained the highest methane yield 123.4NL/kg dry matter. Therefore, it is recommended to interrupt pre-aeration before its cooling stage to switch to anaerobic landfilling.

  11. Landfilling: Bottom Lining and Leachate Collection

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Manfredi, Simone; Kjeldsen, Peter

    2011-01-01

    , whether composed of soils or geosynthetic barriers, are able to prevent leachate emission to the environment for a relatively long time (50 years or longer), it should be realized that no liner is 100% efficient. However, modern lining systems, which include composite liners and multiple (double, or even......The critical element of a landfill, which is essential for the protection of the environment in general, and prevention of contamination of the underlying soils and groundwater in particular, is the bottom lining system. The major focus of the bottom lining system development is to prevent leachate......, as well as the migration of landfill gas, preventing contact between gas and groundwater. The bottom lining system is composed of a relatively impermeable liner or lining system. This very low hydraulic conductivity system controls the movement of the leachate out of the landfill. The bottom lining system...

  12. Bioenergy recovery from landfill gas: A case study in China

    Institute of Scientific and Technical Information of China (English)

    Wei WANG; Yuxiang LUO; Zhou DENG

    2009-01-01

    Landfill gas (LFG) utilization which means a synergy between environmental protection and bioenergy recovery was investigated in this study. Pressure swing adsorption technology was used in LFG purification, and laboratory experiment, pilot-scale test, and on-site demon-stration were carried out in Shenzhen, China. In the laboratory experiment, A-type carbon molecular sieve was selected as the adsorbent by comparison of several other adsorbents. The oPtimal adsorption pressure and adsorp-tion time were 0.25 MPa and 2 min, respectively, under which the product generation rate was 4.5 m3/h and the methane concentration was above 90%. The process and optimization of the pilot-scale test were also reported in the paper. The product gas was of high quality compared with the National Standard of Compressed Natural Gas as Vehicle Fuel (GB 18047-2000), when the air concentration in feed gas was under 10.96%. The demonstration project was composed of a collection system, production system,and utilization system. The drive performance, environ-mental protection performance, and economic feasibility of the product gas -- as alternative fuel in passenger car,truck, and bulldozer-were tested, showing the feasibility technology for LFG utilization.

  13. US EPA record of decision review for landfills: Sanitary landfill (740-G), Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    1993-06-01

    This report presents the results of a review of the US Environmental Protection Agency (EPA) Record of Decision System (RODS) database search conducted to identify Superfund landfill sites where a Record of Decision (ROD) has been prepared by EPA, the States or the US Army Corps of Engineers describing the selected remedy at the site. ROD abstracts from the database were reviewed to identify site information including site type, contaminants of concern, components of the selected remedy, and cleanup goals. Only RODs from landfill sites were evaluated so that the results of the analysis can be used to support the remedy selection process for the Sanitary Landfill at the Savannah River Site (SRS).

  14. Landfill stabilization focus area: Technology summary

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-06-01

    Landfills within the DOE Complex as of 1990 are estimated to contain 3 million cubic meters of buried waste. The DOE facilities where the waste is predominantly located are at Hanford, the Savannah River Site (SRS), the Idaho National Engineering Laboratory (INEL), the Los Alamos National Laboratory (LANL), the Oak Ridge Reservation (ORR), the Nevada Test Site (NTS), and the Rocky Flats Plant (RFP). Landfills include buried waste, whether on pads or in trenches, sumps, ponds, pits, cribs, heaps and piles, auger holes, caissons, and sanitary landfills. Approximately half of all DOE buried waste was disposed of before 1970. Disposal regulations at that time permitted the commingling of various types of waste (i.e., transuranic, low-level radioactive, hazardous). As a result, much of the buried waste throughout the DOE Complex is presently believed to be contaminated with both hazardous and radioactive materials. DOE buried waste typically includes transuranic-contaminated radioactive waste (TRU), low-level radioactive waste (LLW), hazardous waste per 40 CFR 26 1, greater-than-class-C waste per CFR 61 55 (GTCC), mixed TRU waste, and mixed LLW. The mission of the Landfill Stabilization Focus Area is to develop, demonstrate, and deliver safer,more cost-effective and efficient technologies which satisfy DOE site needs for the remediation and management of landfills. The LSFA is structured into five technology areas to meet the landfill remediation and management needs across the DOE complex. These technology areas are: assessment, retrieval, treatment, containment, and stabilization. Technical tasks in each of these areas are reviewed.

  15. Electrocoagulation and decolorization of landfill leachate

    Science.gov (United States)

    Mussa, Zainab Haider; Othman, Mohamed Rozali; Abdullah, Md Pauzi

    2013-11-01

    In this study, several operating conditions such as electrode material, treatment time, applied voltage, Cl□ concentration and PH of solution were tested on treatability of landfill leachate by using electrocoagulation (EC) method. According to the results, EC method can be used efficiently for the treatment of landfill leachate by using proper operating conditions. The best removal rats were obtained when C (rod) electrode as anode, operating time is 120 min, voltage applied is 10 V, NaCl concentration is 5.85 g/L and the raw PH, for these conditions, 70% color removal was obtained.

  16. Ground-water quality and geochemical processes at a municipal landfill, Town of Brookhaven, Long Island, New York

    Science.gov (United States)

    Pearsall, Kenneth A.; Aufderheide, Mary Jean

    1995-01-01

    The principal geochemical process within a plume of leachate-contaminated ground water downgradient from the municipal landfill in the Town of Brookhaven is the oxidation of organic matter. Concurrent reducing processes are the reduction of iron and manganese oxyhydroxides to soluble ferrous and manganous forms, of nitrate and nitrite to nitrogen and ammonia, of sulfate to sulfide (sulfide precipitates from solution as iron and manganese sulfides), and, under extreme conditions, of some organic matter to methane. Secondary processes unrelated to bacterial activity and redox processes are the exchange of dissolved sodium and potassium for calcium and magnesium at ion-exchange sites and the dissolution of calcium and magnesium silicate minerals; these processes cause sodium and potassium concentrations to decrease with depth and with distance from the landfill and cause calcium, magnesium, and silica concentrations to increase.

  17. Valuation of environmental problems in landfill deposition and composting - test of methodology; Verdsetting av miljoekonsekvenser av avfallsdeponering og kompostering - metodeutproeving

    Energy Technology Data Exchange (ETDEWEB)

    Leknes, Einar; Movik, Espen; Wiik, Ragnhild; Meissnes, Rudolf

    1995-08-01

    This study is aimed at the tests and design of methods for valuation of environmental problems associated with the landfill deposition of household waste. An extensive review of literature has been conducted with respect to the environmental impacts and valuation methods. Environmental impact assessment and valuation with respect to emission of greenhouse gases (GHG's), leachate and disamenity, have been performed for 4 Norwegian landfills. These differ in their approach towards waste treatment in terms of GHG-collection, briquette production and composting and also in their location in terms of proximity to residential areas and the quality of natural recipients. The study shows that the collection of methane and production of briquettes causes major reductions in the generation of GHG's, whereas composting brings significant reductions for all types of environmental impacts. (author)

  18. Designing systems for landfill gas migration control in Minnesota

    Energy Technology Data Exchange (ETDEWEB)

    Cannon, J. [Camp, Dresser & McKee, Inc., St. Paul, MN (United States)

    1996-11-01

    Camp, Dresser & McKee (CDM) has designed or is in the process of designing several landfill gas migration control systems in Minnesota. The systems are for both active and closed municipal solid waste landfills. The sites have a variety of covers, including geomembranes, clay caps, and non-engineered soil covers. The control system types include small perimeter systems, full-site systems and phased systems for active sites. Figure 1 shows the locations of the systems CDM is working on in Minnesota. This paper focuses on four sites: Oak Grove Landfill, Hopkins Landfill, Washington County Landfill, and Elk River Landfill. Table 1 provides an outline of the individual site characteristics. The first three sites are closed landfills. The Oak Grove Landfill system was designed and constructed for a group of industries responsible for closure and remedial action. The Hopkins and Washington County landfills are under the control of the Minnesota Pollution Control Agency (MPCA). The MPCA enacted a remedial action program at closed landfills, taking over responsibility for long-term liability under the terms of legally binding agreements negotiated with the site owners. The Elk River Landfill is an active, privately-owned facility. The migration problems and solutions developed for these four landfills are generally descriptive of all the landfills CDM is working on in Minnesota. All landfills have unique characteristics requiring site-specific solutions. CDM, after designing a number of migration control systems in Minnesota, is able to provide a generalized description of design options for specific types of sites. This paper discussions design options used to address different cover types, aesthetic needs, and waste depths, and includes a discussion of design needs for cold climates. A brief case history of the Oak Grove Landfill is included.

  19. Microbial diversity and dynamics during methane production from municipal solid waste

    Energy Technology Data Exchange (ETDEWEB)

    Bareither, Christopher A., E-mail: christopher.bareither@colostate.edu [Civil and Environmental Engineering, Colorado State University, Ft. Collins, CO 80532 (United States); Geological Engineering, University of Wisconsin-Madison, Madison, WI 53706 (United States); Wolfe, Georgia L., E-mail: gwolfe@wisc.edu [Bacteriology, University of Wisconsin-Madison, Madison, WI 53706 (United States); McMahon, Katherine D., E-mail: tmcmahon@engr.wisc.edu [Bacteriology, Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, WI 53706 (United States); Benson, Craig H., E-mail: chbenson@wisc.edu [Civil and Environmental Engineering, Geological Engineering, University of Wisconsin-Madison, Madison, WI 53706 (United States)

    2013-10-15

    Highlights: ► Similar bacterial communities developed following different start-up operation. ► Total methanogens in leachate during the decelerated methane phase reflected overall methane yield. ► Created correlations between methanogens, methane yield, and available substrate. ► Predominant bacteria identified with syntrophic polysaccharide degraders. ► Hydrogenotrophic methanogens were dominant in the methane generation process. - Abstract: The objectives of this study were to characterize development of bacterial and archaeal populations during biodegradation of municipal solid waste (MSW) and to link specific methanogens to methane generation. Experiments were conducted in three 0.61-m-diameter by 0.90-m-tall laboratory reactors to simulate MSW bioreactor landfills. Pyrosequencing of 16S rRNA genes was used to characterize microbial communities in both leachate and solid waste. Microbial assemblages in effluent leachate were similar between reactors during peak methane generation. Specific groups within the Bacteroidetes and Thermatogae phyla were present in all samples and were particularly abundant during peak methane generation. Microbial communities were not similar in leachate and solid fractions assayed at the end of reactor operation; solid waste contained a more abundant bacterial community of cellulose-degrading organisms (e.g., Firmicutes). Specific methanogen populations were assessed using quantitative polymerase chain reaction. Methanomicrobiales, Methanosarcinaceae, and Methanobacteriales were the predominant methanogens in all reactors, with Methanomicrobiales consistently the most abundant. Methanogen growth phases coincided with accelerated methane production, and cumulative methane yield increased with increasing total methanogen abundance. The difference in methanogen populations and corresponding methane yield is attributed to different initial cellulose and hemicellulose contents of the MSW. Higher initial cellulose and

  20. Methane and Climate Change

    NARCIS (Netherlands)

    Reay, D.; Smith, P.; Amstel, van A.R.

    2010-01-01

    Methane is a powerful greenhouse gas and is estimated to be responsible for approximately one-fifth of man-made global warming. Per kilogram, it is 25 times more powerful than carbon dioxide over a 100-year time horizon -- and global warming is likely to enhance methane release from a number of sour

  1. 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.

  2. Microbiological indication of municipal solid waste landfill non-stabilization

    Institute of Scientific and Technical Information of China (English)

    ZHOU Qi-xing; SYLVESTER Runyuzi; YU Ji-yu; ZHANG Qian-ru

    2004-01-01

    Accidental collapse resulted from unstable factors is an important technological problem to be solved in sanitary landfill. Microbiological degradation of organic matters in landfilled solid waste are an important unstable factor. A landfill reactor was thus manufactured and installed to examine quantitative and population dynamics of microorganisms during degradation of landfilled solid waste. It was showed that unstable landfill can be reflected and indicated by microbiological features such as rapidly decreased growth amount of microorganisms, no detection of fungi and actinomyces, and changing the dominant population into methanogenic bacteria and Acinotobacter.

  3. Influence of landfill structures on stabilization of fully recycled leachate

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The experiment was conducted to treat the leachate from two simulating columns by recycling to the columns themselves without being discharged into the enviroment. The columns were employed to simulate anaerobic and semi-aerobic landfills separately. The influence of landfill structure on stabilization of fully recycled leachate was studied. The results show that semi-aerobic landfill structure accelerates the stabilization of leachate recycled. The full recycle of leachate in semi-aerobic landfill is a very feasible and effective technology for leachate treatment with low cost and energy saving especially in arid and rare rainfall regions. Meanwhile, the environmental impact of landfill can be greatly minimized.

  4. Back-Analyses of Landfill Instability Induced by High Water Level: Case Study of Shenzhen Landfill

    Directory of Open Access Journals (Sweden)

    Ren Peng

    2016-01-01

    Full Text Available In June 2008, the Shenzhen landfill slope failed. This case is used as an example to study the deformation characteristics and failure mode of a slope induced by high water levels. An integrated monitoring system, including water level gauges, electronic total stations, and inclinometers, was used to monitor the slope failure process. The field measurements suggest that the landfill landslide was caused by a deep slip along the weak interface of the composite liner system at the base of the landfill. The high water level is considered to be the main factor that caused this failure. To calculate the relative interface shear displacements in the geosynthetic multilayer liner system, a series of numerical direct shear tests were carried out. Based on the numerical results, the composite lining system simplified and the centrifuge modeling technique was used to quantitatively evaluate the effect of water levels on landfill instability.

  5. LANDFILLS AS BIOREACTORS: RESEARH AT THE OUTER LOOP LANDFILL, LOUISVILLE, KENTUCKY; FIRST INTERIM REPORT

    Science.gov (United States)

    Interim report resulting from a cooperative research and development agreement (CRADA) between US EP A's Officeof Research and Development - National Risk Management Research Laboratory and a n ongoing field demonstrationof municipal waste landfills being operated as bioreact...

  6. Numerical analysis of helium-heated methane/steam reformer

    Science.gov (United States)

    Mozdzierz, M.; Brus, G.; Kimijima, S.; Szmyd, J. S.

    2016-09-01

    One of the most promising between many high temperature nuclear reactors applications is to produce hydrogen with heat gained. The simplest and the best examined method is steam reforming of methane. The fabricated hydrogen has wide range of use, for example can be electrochemically oxidized in fuel cells. However, heat management inside methane/steam reformer is extremely important because huge temperature gradients can cause catalyst deactivation. In this work the analysis of temperature field inside helium-heated methane/steam reformer is presented. The optimal system working conditions with respect to methane conversion rate are proposed.

  7. The Comet Assay for the Evaluation of Genotoxic Potential of Landfill Leachate

    Directory of Open Access Journals (Sweden)

    Kamila Widziewicz

    2012-01-01

    Full Text Available Genotoxic assessment of landfill leachate before and after biological treatment was conducted with two human cell lines (Me45 and NHDF and Daphnia magna somatic cells. The alkali version of comet assay was used to examine genotoxicity of leachate by DNA strand breaks analysis and its repair dynamics. The leachate samples were collected from Zabrze landfill, situated in the Upper Silesian Industrial District, Poland. Statistically significant differences (Kruskal-Wallice ANOVA rank model were observed between DNA strand breaks in cells incubated with leachate before and after treatment (P<0.001. Nonparametric Friedman ANOVA confirmed time-reliable and concentration-reliable cells response to leachate concentration. Examinations of chemical properties showed a marked decrease in leachate parameters after treatment which correlate to reduced genotoxicity towards tested cells. Obtained results demonstrate that biological cotreatment of leachate together with municipal wastewater is an efficient method for its genotoxic potential reduction; however, treated leachate still possessed genotoxic character.

  8. Product specific emissions from municipal solid waste landfills

    DEFF Research Database (Denmark)

    Nielsen, Per Henning; Hauschild, Michael Zwicky

    1998-01-01

    For the inventory analysis of environmental impacts associated with products in LCA there is a great need for estimates of emissions from waste products disposed at municipal solid waste landfills (product specific emissions). Since product specific emissions can not be calculated or measured...... directly at the landfills, they must be estimated by modelling of landfill processes. This paper presents a landfill model based on a large number of assumptions and approximations concerning landfill properties, waste product properties and characteristics of various kinds of environmental protection...... systems (e.g. landfill gas combustion units and leachate treatment units). The model is useful for estimation of emissions from waste products disposed in landfills and it has been made operational in the computer tool LCA-LAND presented in a following paper. In the model, waste products are subdivided...

  9. Carbon Dioxide/Methane Separation by Adsorption on Sepiolite

    Institute of Scientific and Technical Information of China (English)

    José A.Delgado; María A.Uguina; José L.Sotelo; Beatriz Ruíz; Marcio Rosário

    2007-01-01

    In this work,the use of sepiolite for the removal of carbon dioxide from a carbon dioxide/methane mixture by a pressure swing adsorption (PSA) process has been researched.Adsorption equilibrium and kinetics have been measured in a fixed-bed.and the adsorption equilibrium parameters of carbon dioxide and methane on sepiolite have been obtained.A model based on the LDF approximation has been employed to simulate the fixed-bed kinetics.using the Langmuir equation to describe the adsotption equilibrium isotherm.The functioning of a PSA cycle for separating carbon dioxide/methane mixtures using sepiolite as adsorbent has also been studied.The experimental results were compared with the ones predicted by the model adapted to a PSA system.Methane with purity higher than 97% can be obtained from feeds containing carbon dioxide with concentrations ranging from 34% to 56% with the proposed PSA cycle.These results suggest that sepiolite is an adsorbent with good properties for its employment in a PSA cycle for carbon dioxide removal from landfill gases.

  10. Highly cost-effective and sulfur/coking resistant VOx-grafted TiO2 nanoparticles as an efficient anode catalyst for direct conversion of dry sour methane in solid oxide fuel cells

    NARCIS (Netherlands)

    Garcia, A.; Yan, N.; Vincent, A.; Singh, A.; Hill, J.M.; Chuang, K. T.; Luo, J.L.

    2015-01-01

    In this work, we show that grafted metal oxide can be a highly cost-effective and active anode for solid oxide fuel cells for sour methane conversion. The developed electro-catalyst was composed of vanadium oxide grafted TiO2 nanoparticles (VOx/TiO2) infiltrated into a porous La0.4Sr0.5Ba0.1TiO3+δ e

  11. Intrinsic bioremediation of landfills interim report

    Energy Technology Data Exchange (ETDEWEB)

    Brigmon, R.L. [Westinghouse Savannah River Company, Aiken, SC (United States); Fliermans, C.B.

    1997-07-14

    Intrinsic bioremediation is a risk management option that relies on natural biological and physical processes to contain the spread of contamination from a source. Evidence is presented in this report that intrinsic bioremediation is occurring at the Sanitary Landfill is fundamental to support incorportion into a Corrective Action Plan (CAP).

  12. Assessing the market opportunities of landfill mining

    NARCIS (Netherlands)

    van der Zee, D.J.; Achterkamp, M.C.; de Visser, B.J.

    2004-01-01

    Long-term estimates make clear that the amount of solid waste to be processed at landfills in the Netherlands will sharply decline in coming years. Major reasons can be found in the availability of improved technologies for waste recycling and government regulations aiming at waste reduction. Conseq

  13. Assessing the opportunities of landfill mining

    NARCIS (Netherlands)

    Zee, D.J. van der; Achterkamp, M.C.; Visser, B.J. de

    2003-01-01

    Long-term estimates make clear that the amount of solid waste to be processed at landfills in the Netherlands will sharply decline in coming years. Major reasons can be found in the availability of improved technologies for waste recycling and government regulations aiming at waste reduction. Conseq

  14. BIOREACTOR DESIGN - OUTER LOOP LANDFILL, LOUISVILLE, KY

    Science.gov (United States)

    Bioreactor field demonstration projects are underway at the Outer Loop Landfill in Louisville, KY, USA. The research effort is a cooperative research effort between US EPA and Waste Management Inc. Two primary kinds of municipal waste bioreactors are under study at this site. ...

  15. Further study of the intrinsic safety of internally shorted lithium and lithium-ion cells within methane-air.

    Science.gov (United States)

    Dubaniewicz, Thomas H; DuCarme, Joseph P

    2014-11-01

    National Institute for Occupational Safety and Health (NIOSH) researchers continue to study the potential for lithium and lithium-ion battery thermal runaway from an internal short circuit in equipment for use in underground coal mines. Researchers conducted cell crush tests using a plastic wedge within a 20-L explosion-containment chamber filled with 6.5% CH4-air to simulate the mining hazard. The present work extends earlier findings to include a study of LiFePO4 cells crushed while under charge, prismatic form factor LiCoO2 cells, primary spiral-wound constructed LiMnO2 cells, and crush speed influence on thermal runaway susceptibility. The plastic wedge crush was a more severe test than the flat plate crush with a prismatic format cell. Test results indicate that prismatic Saft MP 174565 LiCoO2 and primary spiral-wound Saft FRIWO M52EX LiMnO2 cells pose a CH4-air ignition hazard from internal short circuit. Under specified test conditions, A123 systems ANR26650M1A LiFePO4 cylindrical cells produced no chamber ignitions while under a charge of up to 5 A. Common spiral-wound cell separators are too thin to meet intrinsic safety standards provisions for distance through solid insulation, suggesting that a hard internal short circuit within these cells should be considered for intrinsic safety evaluation purposes, even as a non-countable fault. Observed flames from a LiMnO2 spiral-wound cell after a chamber ignition within an inert atmosphere indicate a sustained exothermic reaction within the cell. The influence of crush speed on ignitions under specified test conditions was not statistically significant.

  16. Global and regional methane budget and its inter-annual variability

    Science.gov (United States)

    Bourakkadi, Zakia; Payan, Sébastien; Locatelli, Robin; Chevallier, Frederic; Saunois, Marielle; Bousquet, Philippe

    2016-04-01

    Methane global concentration has more than doubled since the pre-industrial times. This increase is generally caused by the anthropogenic activities like the massive use and extraction of fossil fuel, rice paddies agriculture and emissions from landfills. Space observations are very useful to monitor and quantify methane concentration in the atmosphere, in order to improve our knowledge of its sources, sinks, transport and trends. Since 2002 global methane total-columns mixing ratois from the SCanning Imaging Absorption spectroMeter for Atmospheric ChartographY (SCIAMACHY) on board ENVISAT was the first space-borne sensitive to methane in the boundary layer. However the communication with the instrument was lost in April 2012. Since January 2009 methane columns retrievals have been available also from the Thermal And Near Infrared Sensor for carbon Observations-Fourier Transform Spectrometer (TANSO-FTS), on-board the GOSAT satellite. In this study, we used measurements in the short wave infrared radiation (SWIR) from TANSO-FTS covering 5 years, from January 2010 to December 2014 to estimate global methane fluxes by inverse modeling, using the PYVAR-LMDZ model. We present here the results of global and regional methane budget, and its inter-annual variability during this period.

  17. In-Situ Quantification of Methanotrophic Activity in a Landfill Cover Soil Using Gas Push-Pull Tests

    Science.gov (United States)

    Gomez, K. E.; Gonzalez-Gil, G.; Schroth, M. H.; Zeyer, J.

    2007-12-01

    Landfills are both a major anthropogenic source and a sink for the greenhouse gas CH4. Methanogenic bacteria produce CH4 during the anaerobic digestion of landfill waste, whereas, methanotrophic bacteria consume CH4 as it is transported through a landfill cover soil. Methanotrophs are thought to be ubiquitous in soils, but typically exist in large numbers at oxic/anoxic interfaces, close to anaerobic methane sources but exposed to oxygen required for metabolism. Accurate in-situ quantification of the sink strength of methanotrophs in landfill cover soils is needed for global carbon balances and for local emissions mitigation strategies. We measured in-situ CH4 concentrations at 30, 60, and 100 cm depth at 18 evenly spaced locations across a landfill cover soil. Furthermore, we performed Gas Push-Pull Tests (GPPTs) to estimate in-situ rates of methanotrophic activity in the cover soil. The GPPT is a gas-tracer test in which a gas mixture containing CH4, O2, and non-reactive tracer gases is injected (pushed) into the soil followed by extraction (pull) from the same location. Quantification of CH4 oxidation rates is based upon comparison of the breakthrough curves of CH4 and tracer gases. We present the results of a series of GPPTs conducted at two locations in the cover soil to assess the feasibility and reproducibility of this technique to quantify methanotrophic activity. Additional GPPTs were performed with a methanotrophic inhibitor in the injection gas mixture to confirm the appropriate choice of tracers to quantify CH4 oxidation. Estimated CH4 oxidation rate constants indicate that the cover soil contains a highly active methanotrophic community.

  18. A High-precision Near-infrared Survey for Radial Velocity Variable Low-mass Stars Using CSHELL and a Methane Gas Cell

    Science.gov (United States)

    Gagné, Jonathan; Plavchan, Peter; Gao, Peter; Anglada-Escude, Guillem; Furlan, Elise; Davison, Cassy; Tanner, Angelle; Henry, Todd J.; Riedel, Adric R.; Brinkworth, Carolyn; Latham, David; Bottom, Michael; White, Russel; Mills, Sean; Beichman, Chas; Johnson, John A.; Ciardi, David R.; Wallace, Kent; Mennesson, Bertrand; von Braun, Kaspar; Vasisht, Gautam; Prato, Lisa; Kane, Stephen R.; Mamajek, Eric E.; Walp, Bernie; Crawford, Timothy J.; Rougeot, Raphaël; Geneser, Claire S.; Catanzarite, Joseph

    2016-05-01

    We present the results of a precise near-infrared (NIR) radial velocity (RV) survey of 32 low-mass stars with spectral types K2-M4 using CSHELL at the NASA InfraRed Telescope Facility in the K band with an isotopologue methane gas cell to achieve wavelength calibration and a novel, iterative RV extraction method. We surveyed 14 members of young (≈25-150 Myr) moving groups, the young field star ɛ Eridani, and 18 nearby (GJ 876 bc and independently retrieve orbital parameters consistent with previous studies. We recovered RV variabilities for HD 160934 AB and GJ 725 AB that are consistent with their known binary orbits, and nine other targets are candidate RV variables with a statistical significance of 3σ-5σ. Our method, combined with the new iSHELL spectrograph, will yield long-term RV precisions of ≲5 m s-1 in the NIR, which will allow the detection of super-Earths near the habitable zone of mid-M dwarfs.

  19. 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.

  20. Advanced manufacturing of intermediate temperature, direct methane oxidation membrane electrode assemblies for durable solid oxide fuel cell Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ITN proposes to create an innovative anode supported membrane electrode assembly (MEA) for solid oxide fuel cells (SOFCs) that is capable of long-term operation at...

  1. Identification of a Methane Oxidation Intermediate on Solid Oxide Fuel Cell Anode Surfaces with Fourier Transform Infrared Emission.

    Science.gov (United States)

    Pomfret, Michael B; Steinhurst, Daniel A; Owrutsky, Jeffrey C

    2013-04-18

    Fuel interactions on solid oxide fuel cell (SOFC) anodes are studied with in situ Fourier transform infrared emission spectroscopy (FTIRES). SOFCs are operated at 800 °C with CH4 as a representative hydrocarbon fuel. IR signatures of gas-phase oxidation products, CO2(g) and CO(g), are observed while cells are under load. A broad feature at 2295 cm(-1) is assigned to CO2 adsorbed on Ni as a CH4 oxidation intermediate during cell operation and while carbon deposits are electrochemically oxidized after CH4 operation. Electrochemical control provides confirmation of the assignment of adsorbed CO2. FTIRES has been demonstrated as a viable technique for the identification of fuel oxidation intermediates and products in working SOFCs, allowing for the elucidation of the mechanisms of fuel chemistry.

  2. La0.6Sr0.4Co0.2Fe0.8O3 Perovskite: A Stable Anode Catalyst for Direct Methane Solid Oxide Fuel Cells

    Directory of Open Access Journals (Sweden)

    Jelvehnaz Mirzababaei

    2014-05-01

    Full Text Available Direct methane solid oxide fuel cells, operated by supplying methane to a Ni/YSZ anode, suffer from degradation via accumulation of carbon deposits on the Ni surface. Coating a 40 µm thin film of La0.6Sr0.4Co0.2Fe0.8O3 (LSCF perovskite on the Ni/YSZ anode surface decreased the amount of carbon deposits, slowing down the degradation rate. The improvement in anode durability could be related to the oxidation activity of LSCF which facilitates oxidation of CH4 and carbon deposits. Analysis of the crystalline structure of LSCF revealed that LSCF was stable in the reducing anode environment under H2 and CH4 flow at 750 °C and retained its perovskite structure throughout the 475 h long-term stability test.

  3. A Monolithically Integrated Gallium Nitride Nanowire/Silicon Solar Cell Photocathode for Selective Carbon Dioxide Reduction to Methane.

    Science.gov (United States)

    Wang, Yichen; Fan, Shizhao; AlOtaibi, Bandar; Wang, Yongjie; Li, Lu; Mi, Zetian

    2016-06-20

    A gallium nitride nanowire/silicon solar cell photocathode for the photoreduction of carbon dioxide (CO2 ) is demonstrated. Such a monolithically integrated nanowire/solar cell photocathode offers several unique advantages, including the absorption of a large part of the solar spectrum and highly efficient carrier extraction. With the incorporation of copper as the co-catalyst, the devices exhibit a Faradaic efficiency of about 19 % for the 8e(-) photoreduction to CH4 at -1.4 V vs Ag/AgCl, a value that is more than thirty times higher than that for the 2e(-) reduced CO (ca. 0.6 %).

  4. Further study of the intrinsic safety of internally shorted lithium and lithium-ion cells within methane-air

    OpenAIRE

    Dubaniewicz, Thomas H.; DuCarme, Joseph P.

    2014-01-01

    National Institute for Occupational Safety and Health (NIOSH) researchers continue to study the potential for lithium and lithium-ion battery thermal runaway from an internal short circuit in equipment for use in underground coal mines. Researchers conducted cell crush tests using a plastic wedge within a 20-L explosion-containment chamber filled with 6.5% CH4-air to simulate the mining hazard. The present work extends earlier findings to include a study of LiFePO4 cells crushed while under c...

  5. Performance evaluation of an anaerobic/aerobic landfill-based digester using yard waste for energy and compost production.

    Science.gov (United States)

    Yazdani, Ramin; Barlaz, Morton A; Augenstein, Don; Kayhanian, Masoud; Tchobanoglous, George

    2012-05-01

    The objective of this study was to evaluate a new alternative for yard waste management by constructing, operating and monitoring a landfill-based two-stage batch digester (anaerobic/aerobic) with the recovery of energy and compost. The system was initially operated under anaerobic conditions for 366 days, after which the yard waste was aerated for an additional 191 days. Off gas generated from the aerobic stage was treated by biofilters. Net energy recovery was 84.3MWh, or 46kWh per million metric tons of wet waste (as received), and the biochemical methane potential of the treated waste decreased by 83% during the two-stage operation. The average removal efficiencies of volatile organic compounds and non-methane organic compounds in the biofilters were 96-99% and 68-99%, respectively.

  6. Are termite mounds biofilters for methane? - Challenges and new approaches to quantify methane oxidation in termite mounds

    Science.gov (United States)

    Nauer, Philipp A.; Hutley, Lindsay B.; Bristow, Mila; Arndt, Stefan K.

    2015-04-01

    Methane emissions from termites contribute around 3% to global methane in the atmosphere, although the total source estimate for termites is the most uncertain among all sources. In tropical regions, the relative source contribution of termites can be far higher due to the high biomass and relative importance of termites in plant decomposition. Past research focused on net emission measurements and their variability, but little is known about underlying processes governing these emissions. In particular, microbial oxidation of methane (MOX) within termite mounds has rarely been investigated. In well-studied ecosystems featuring an oxic matrix above an anoxic methane-producing habitat (e.g. landfills or sediments), the fraction of oxidized methane (fox) can reach up to 90% of gross production. However, conventional mass-balance approaches to apportion production and consumption processes can be challenging to apply in the complex-structured and almost inaccessible environment of a termite mound. In effect, all field-based data on termite-mound MOX is based on one study that measured isotopic shifts in produced and emitted methane. In this study a closed-system isotope fractionation model was applied and estimated fox ranged from 10% to almost 100%. However, it is shown here that by applying an open-system isotope-pool model, the measured isotopic shifts can also be explained by physical transport of methane alone. Different field-based methods to quantify MOX in termite mounds are proposed which do not rely on assumptions of physical gas transport. A simple approach is the use of specific inhibitors for MOX, e.g. difluoromethane (CH2F2), combined with chamber-based flux measurements before and after their application. Data is presented on the suitability of different inhibitors and first results of their application in the field. Alternatively, gas-tracer methods allow the quantification of methane oxidation and reaction kinetics without knowledge of physical gas

  7. Application of Electrochemical Process in Removal of Heavy Metals from Landfill Leachate

    Directory of Open Access Journals (Sweden)

    Mostafaii Gh.1 PhD,

    2016-08-01

    Full Text Available Aims Municipal landfill leachate contains high concentrations of heavy metals, organics, ammonia. The efficeincy of electrochemically removal of heavy metals from landfill leachate was studied. Materials & Methods The leachate was obtained from Kahrizak landfill in south of Tehran. The experiments were carried out by batch process. The 2liter batch reactor was made of glass. There were eight anodes and cathodes electrodes. The electrodes were placed vertically parallel to each other and they were connected to a digital DC power supply. The pH and conductivity were adjusted to a desirable value using NaOH or H2SO4, and NaCl. All the runs were performed at constant temperature of 25°C. In each run, 1.5liter of the leachate was placed into the electrolytic cell. Samples were extracted every 10min and then filtered through a mixed cellulose acetate membrane (0.42μm. The amount of Lead, Zinc and Nickel removal was measured at pH=7 and in current density of 0.5, 0.75, and 1A. Findings When current density and time reaction increased, removal efficiency of heavy metals such as Lead, Zinc and Nickel increased. At initial pH=7, density 1A and reaction time= 60min, Lead, Nickel and Zinc were removed up to 86, 93 and 95%, respectively. Conclusion Electrochemical process can be proposed as a suitable technique to remove heavy metal from landfill leachate.

  8. Methane and Ethane Measurements from a New TCCON Station in Los Angeles

    Science.gov (United States)

    Wunch, D.; Roehl, C. M.; Blavier, J. L.; Allen, N.; Treffers, R.; Toon, G. C.; Wennberg, P. O.

    2012-12-01

    The Los Angeles urban region emits large amounts of methane (~0.44Tg/year) into the atmosphere. It is currently unclear exactly how much of this is biogenic (landfills, cattle), and how much is from natural gas (natural seeps or fugitive emissions from the natural gas infrastructure). Since natural gas contains ethane, whereas biogenic emissions contain none, simultaneous measurements of ethane and methane offer the possibility of separating the biogenic versus natural gas emissions of methane. We investigate this using total column measurements from a new Total Carbon Column Observing Network (TCCON) remote sensing station in the Los Angeles suburb of Pasadena, which began measurements in July 2012. These measurements will be put into the context of historical remote sensing and in situ measurements described by Wennberg et al., 2012 (doi:10.1021/es301138y).

  9. Utilization of stabilized wastes for reducing methane emission from municipal solid waste disposal.

    Science.gov (United States)

    Chiemchaisri, Wilai; Chiemchaisri, Chart; Boonchaiyuttasak, Jindaruch

    2013-08-01

    Stabilized solid wastes were utilized to mitigate methane emission from the landfill. Loose texture of plastic wastes encouraged air diffusion from the soil surface whereas fine organic fraction has good water holding capacity and nutrients to stimulate methane oxidation reaction. Biological methane oxidation capacity in stabilized waste layer was found to be up to 34.1 g/m(3)d. Microbial activity test revealed methanotrophic activities of plastic and degraded organic wastes were in the same order. The mixture of plastic and fine degraded organic waste matrix provided sufficient porosity for oxygen transfer and supported the growth of methanotrophs throughout 0.8m depth of waste layer. Fluorescent in situ hybridization (FISH) analysis confirmed the presence of methanotrophs and their population was found varied along waste depth.

  10. Performance of geotextiles in landfills covers

    Energy Technology Data Exchange (ETDEWEB)

    Reitz, L.J.; Holtz, R.D.

    1997-11-01

    As part of the research into the performance of geotextiles in landfill covers, 14 test pits were excavated in five landfill covers constructed between 1988 and 1992 in Washington State. Materials used in the drainage system were examined and documented. Specimens of geotextiles (all 8 oz/yd{sup 2}, needle punched nonwovens) as well as samples of the vegetative and sand drainage soils, were obtained for laboratory analyses. Laboratory tests indicated that the geotextiles satisfactorily performed their intended filtration function. No apparent migration of fines into the drainage layer was detected. The degree of clogging was evaluated by performing permittivity tests on specimens of the exhumed geotextiles, as retrieved and after washing. Washing typically resulted in permittivity increases on the order of 30 to 90 percent.

  11. Landfill liners from dam reservoir sediments

    Directory of Open Access Journals (Sweden)

    Koś Karolina

    2016-03-01

    Full Text Available Landfill liners from dam reservoir sediments. Every municipal solid waste landfill has to be properly secured to protect the natural environment from possible leachate. Most often an artificial sealing is used, which is based on a soil liner from cohesive soils (clays, silts. Usability evaluation of bottom sediments from Rzeszowski Reservoir for building these liners was presented in the paper. Sediments from dam reservoirs, gathered as a result of the siltation process, can be a valuable material for earthworks purposes. Determination of their possible ways of usage is important, especially before the planned dredging, because thanks to that this material will not be put on a heap. Based on the analysis of the geotechnical parameters of these sediments it was stated that this material can be preliminary allowed for using in liners.

  12. 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.

  13. Research on Health Risk-Based Radioactive Acceptance Criteria of Municipal Solid Waste Landfill

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The article focuses on the topics of Health Risk-Based Radioactive Acceptance Criteria of Municipal Solid Waste Landfill (MSWL, including municipal refuse landfills or industrial solid waste landfills, MSWL). At first, health risk assessment

  14. Alligator River National Wildlife Refuge : Potential impacts from Dare County Landfills

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Surface runoff or leachate from two landfills (East Lake Landfill and the Dare County Construction and Demolition Debris Landfill) have the potential to impact fish...

  15. Ammonia release and conversion in bioreactor landfill simulators

    Energy Technology Data Exchange (ETDEWEB)

    Lubberding, H.; Valencia, R.; Salazar, R.; Lens, P.

    2009-07-01

    Bioreactor landfills are considered to be an improvements to normal sanitary landfills, because the Municipal Solid Waste is stabilised faster and the biogas is produced in a shorter period of time (Valencia et al 2008a, b). In spite of these advantages, it is still difficult to reach within 30 years a safe status of the landfill due to the elevated NH{sub 4}{sup +} levels (up to 3 g/L) in the leachate. (Author)

  16. Landfill is an important atmospheric mercury emission source

    Institute of Scientific and Technical Information of China (English)

    FENG Xinbin; TANG Shunlin; LI Zhonggen; WANG Shaofeng; LIANG Lian

    2004-01-01

    Since municipal wastes contain refuses with high mercury contents, incineration of municipal wastes becomes the major anthropogenic atmospheric mercury emission source. In China, landfills are however the main way to dispose of municipal wastes. Total gaseous mercury (TGM) concentrations in landfill gas of Gaoyan sanitary landfill located in suburb of Guiyang City were monitored using a high temporal resolved automated mercury analyzer, and mono-methylmercury (MMHg) and dimethylmercury (DMHg) concentrations in landfill gas were also measured using GC coupled with the cold vapor atomic fluorescence (CVAFS) method. Meanwhile, the TGM exchange fluxes between exposed waste and air and the soil surface of the landfill and air, were measured using low Hg blank quartz flux chamber coupled with high temporal resolved automated mercury analyzer technique. TGM concentrations in landfill gas from half year filling area averaged out at 665.52±291.25 ng/m3, which is comparable with TGM concentrations from flue gas of a small coal combustion boiler in Guiyang. The average MMHg and DMHg concentrations averaged out at 2.06±1.82 ng/m3 and 9.50±5.18 ng/m3, respectively. It is proven that mercury emission is the predominant process at the surfaces of both exposed wastes and soil of landfill. Landfills are not only TGM emission source, but also methylmercury emission source to the ambient air. There are two ways to emit mercury to the air from landfills, one is with the landfill gas through landfill gas duct, and the other through soil/air exchange. The Hg emission processes from landfills are controlled by meteorological parameters.

  17. Quantification of long term emission potential from landfills

    OpenAIRE

    Heimovaara, T.J.

    2011-01-01

    Novel approaches for the after-care of Municipal Solid Waste (MSW) landfills are based on technological measures to reduce the long term emission potential in a short time period. Biological degradation in landfills is a means to significantly reduce the long term emission potential. Leachate emission to the groundwater is considered to be one of the largest long-term impacts related to landfilling. Currently we are starting up a research program, partly subsidized by the Dutch Technology fou...

  18. Degradation of Refuse in Hybrid Bioreactor Landfill

    Institute of Scientific and Technical Information of China (English)

    YAN LONG; Yu-YANG LONG; HAI-CHUN LIU; DONG-SHENG SHEN

    2009-01-01

    Objectivess To explore the process of refuse decomposition in hybrid bioreactor landfill. Methods The bioreactor landfill was operated in sequencing of facultative-anaerobic and aerobic conditions with leachate recireulation, pH, COD, and ammonia in the leachate and pH, biodegradable organic matter (BDM), and cation exchange capacity (CEC) in refuse were detected. Results CEC increased gradually with the degradation of refuse, which was negatively correlad, With BDM. COD and ammonia in the leachate was declined to 399.2 mg L-1 and 20.6 mg N L-1, respectively, during the 357-day operation. The respective concentrations of ammonia and COD were below the second and the third levels of current discharge standards in China. Conclusion The refuse is relatively stable at the end of hybrid bioreactor landfill operation. Most of the readily biodegradable organic matter is mineralized in the initial phase of refuse degradation, whereas the hard-biodegradable organic matter is mainly humidified in the maturity phase of refuse degradation.

  19. Proposal Of Landfill Site Model In The Particular Territory

    Directory of Open Access Journals (Sweden)

    Stopka Ondrej

    2015-12-01

    Full Text Available Nowadays, waste logistics is a relevant element within the worldwide logistics system. This paper is focused on the proposal of the appropriate model of landfill site for disposal of municipal waste. This issue refers to waste logistics in urban areas. In this regard, three different alternative models of landfill sites are considered. Landfill site model can significantly influence the waste management productivity and effectiveness of the enterprise. In the paper, one of the decision-making problem methods is utilized. This particular method enables to assess each model of landfill site in relation to each of the specified criterion and order the models according to the achieved results.

  20. Case study: City of Industry landfill gas recovery operation

    Energy Technology Data Exchange (ETDEWEB)

    None

    1981-11-01

    Development of civic, recreation, and conservation facilities throughout a 150-acre site which had been used for waste disposal from 1951 to 1970 is described. The history of the landfill site, the geology of the site, and a test well program to assess the feasibility of recoverying landfill gas economically from the site are discussed. Based on results of the test well program, the City of Industry authorized the design and installation of a full-scale landfill gas recovery system. Design, construction, and operation of the system are described. The landfill gas system provides fuel for use in boilers to meet space heating and hot water demands for site development (MCW)

  1. Modelling the Potential Biogas Productivity Range from a MSW Landfill for Its Sustainable Exploitation

    Directory of Open Access Journals (Sweden)

    Elena Cristina Rada

    2015-01-01

    Full Text Available A model of biogas generation was modified and applied to the case of a sanitary landfill in Italy. The modifications considered the role of the temperature field normally established within each layer of waste. It must be pointed out the temperature affects the anaerobic biodegradation kinetics. In order to assess the effect of moisture on the waste biodegradation rate, on the bacteria process and then on the methane production, the model was compared with the LandGEM one. Information on the initial water content came from data concerning waste composition. No additional information about the hydrological balance was available. Thus, nine sets of kinetic constants, derived by literature, were adopted for the simulations. Results showed a significant variability of the maximal hourly biogas flows on a yearly basis, with consequences for the collectable amount during the operating period of a hypothetical engine. The approach is a useful tool to assess the lowest and highest biogas productivity in order to analyze the viability of biogas exploitation for energy purposes. This is useful also in countries that must plan for biogas exploitation from old and new landfills, as a consequence of developments in the waste sector.

  2. Ground based mobile isotopic methane measurements in the Front Range, Colorado

    Science.gov (United States)

    Vaughn, B. H.; Rella, C.; Petron, G.; Sherwood, O.; Mielke-Maday, I.; Schwietzke, S.

    2014-12-01

    Increased development of unconventional oil and gas resources in North America has given rise to attempts to monitor and quantify fugitive emissions of methane from the industry. Emission estimates of methane from oil and gas basins can vary significantly from one study to another as well as from EPA or State estimates. New efforts are aimed at reconciling bottom-up, or inventory-based, emission estimates of methane with top-down estimates based on atmospheric measurements from aircraft, towers, mobile ground-based vehicles, and atmospheric models. Attributing airborne measurements of regional methane fluxes to specific sources is informed by ground-based measurements of methane. Stable isotopic measurements (δ13C) of methane help distinguish between emissions from the O&G industry, Confined Animal Feed Operations (CAFO), and landfills, but analytical challenges typically limit meaningful isotopic measurements to individual point sampling. We are developing a toolbox to use δ13CH4 measurements to assess the partitioning of methane emissions for regions with multiple methane sources. The method was applied to the Denver-Julesberg Basin. Here we present data from continuous isotopic measurements obtained over a wide geographic area by using MegaCore, a 1500 ft. tube that is constantly filled with sample air while driving, then subsequently analyzed at slower rates using cavity ring down spectroscopy (CRDS). Pressure, flow and calibration are tightly controlled allowing precise attribution of methane enhancements to their point of collection. Comparisons with point measurements are needed to confirm regional values and further constrain flux estimates and models. This effort was made in conjunction with several major field campaigns in the Colorado Front Range in July-August 2014, including FRAPPÉ (Front Range Air Pollution and Photochemistry Experiment), DISCOVER-AQ, and the Air Water Gas NSF Sustainability Research Network at the University of Colorado.

  3. [Isolation of a methane-utilizing Klebsiella sp. strain and its application for detecting methane].

    Science.gov (United States)

    Zheng, Jun; Guo, Jun; Wang, Yujun; Yang, Yujing; Pang, Jinmei; Yang, Suping; Zhao, Gengui; Dong, Chuan

    2009-05-01

    We have isolated a strain C611 that used methane as the sole carbon sources for growth from paddy soil in Taiyuan of Shanxi province. Based on the physiological characteristics and 16S rDNA sequence analysis, we identified the strain as Klebsiella sp.. We used statistic-based experimental design (RSM) to optimize the culture conditions for C611 strain. The optimum conditions were as follows: temperature of 24.4 degrees C, inoculum volume of 6.7% and methane content of 25%. We studied the response time and the relationship between consumption of dissolved oxygen and methane gas contents with PVA-H3BO3 immobilized cell of C611 using electrochemical method. The response time was no more than 100 s of this reaction system, and the linear range of detection of methane content was from 0 to 10%. The standard gas sample 3% methane was measured by this method with the mean content value of 3.09%, RSD of 3.48%, and the relative error of 3%. Hence, it has the potential in developing biosensor for methane.

  4. Experimental and life cycle assessment analysis of gas emission from mechanically–biologically pretreated waste in a landfill with energy recovery

    Energy Technology Data Exchange (ETDEWEB)

    Di Maria, Francesco, E-mail: francesco.dimaria@unipg.it; Sordi, Alessio; Micale, Caterina

    2013-11-15

    Highlights: • Bio-methane landfill emissions from different period (0, 4, 8, 16 weeks) MTB waste have been evaluated. • Electrical energy recoverable from landfill gas ranges from 11 to about 90 kW h/tonne. • Correlation between oxygen uptake, energy recovery and anaerobic gas production shows R{sup 2} ranging from 0.78 to 0.98. • LCA demonstrate that global impact related to gaseous emissions achieve minimum for 4 week of MBT. - Abstract: The global gaseous emissions produced by landfilling the Mechanically Sorted Organic Fraction (MSOF) with different weeks of Mechanical Biological Treatment (MBT) was evaluated for an existing waste management system. One MBT facility and a landfill with internal combustion engines fuelled by the landfill gas for electrical energy production operate in the waste management system considered. An experimental apparatus was used to simulate 0, 4, 8 and 16 weeks of aerobic stabilization and the consequent biogas potential (Nl/kg) of a large sample of MSOF withdrawn from the full-scale MBT. Stabilization achieved by the waste was evaluated by dynamic oxygen uptake and fermentation tests. Good correlation coefficients (R{sup 2}), ranging from 0.7668 to 0.9772, were found between oxygen uptake, fermentation and anaerobic test values. On the basis of the results of several anaerobic tests, the methane production rate k (year{sup −1}) was evaluated. k ranged from 0.436 to 0.308 year{sup −1} and the bio-methane potential from 37 to 12 N m{sup 3}/tonne, respectively, for the MSOF with 0 and 16 weeks of treatment. Energy recovery from landfill gas ranged from about 11 to 90 kW h per tonne of disposed MSOF depending on the different scenario investigated. Life cycle analysis showed that the scenario with 0 weeks of pre-treatment has the highest weighted global impact even if opposite results were obtained with respect to the single impact criteria. MSOF pre-treatment periods longer than 4 weeks showed rather negligible variation

  5. Estimation of emissions of nonmethane organic compounds from a closed landfill site using a landfill gas emission model

    Energy Technology Data Exchange (ETDEWEB)

    Nwachukwu, A.N. [Williamson Research Centre for Molecular Environmental Sciences, School of Earth, Atmospheric and Environmental Science, University of Manchester M13 9PL (United Kingdom); Diya, A.W. [Health Sciences Research Group, School of Medicine, University of Manchester M13 9PL (United Kingdom)

    2013-07-01

    Nonmethane organic compounds (NMOC) emissions from landfills often constitute significant risks both to human health and the general environment. To date very little work has been done on tracking the emissions of NMOC from landfills. To this end, a concerted effort was made to investigate the total annual mass emission rate of NMOC from a closed landfill site in South Manchester, United Kingdom. This was done by using field estimates of NMOC concentration and the landfill parameters into the Landfill Gas Emission Model embedded in ACTS and RISK software. Two results were obtained: (i) a deterministic outcome of 1.7218 x 10-7 kg/year, which was calculated from mean values of the field estimates of NMOC concentration and the landfill parameters, and (ii) a probabilistic outcome of 1.66 x 10-7 - 1.78 x 10-7 kg/year, which is a range of value obtained after Monte Carlo simulation of the uncertain parameters of the landfill including NMOC concentration. A comparison between these two results suggests that the probabilistic outcome is a more representative and reliable estimate of the total annual mass emission of NMOC especially given the variability of the parameters of the model. Moreover, a comparison of the model result and the safety standard of 5.0 x 10-5 kg/year indicate that the mass emission of NMOC from the studied landfill is significantly less than previously thought. However, given that this can accumulate to a dangerous level over a long period of time (such as the age of this landfill site); it may have started affecting the health of the people living within the vicinity of the landfill. A case is therefore made for more studies to be carried out on the emissions of other gases such as CH4 and CO2 from the studied landfill site, as this would help to understand the synergistic effect of the various gases being emitted from the landfill.

  6. Microbial community analysis in a long-term membrane-less microbial electrolysis cell with hydrogen and methane production.

    Science.gov (United States)

    Rago, Laura; Ruiz, Yolanda; Baeza, Juan A; Guisasola, Albert; Cortés, Pilar

    2015-12-01

    A single-chamber microbial electrolysis cell (MEC) aiming at hydrogen production with acetate as sole carbon source failed due to methanogenesis build-up despite the significant amount of 2-bromoethanesulfonate (BES) dosage, 50 mM. Specific batch experiments and a thorough microbial community analysis, pyrosequencing and qPCR, of cathode, anode and medium were performed to understand these observations. The experimental data rebuts different hypothesis and shows that methanogenesis at high BES concentration was likely due to the capacity of some Archaea (hydrogen-oxidizing genus Methanobrevibacter) to resist high BES concentration up to 200 mM. Methanobrevibacter, of the Methanobacteriales order, represented almost the 98% of the total Archaea in the cathode whereas Geobacter was highly abundant in the anode (72% of bacteria). Moreover, at higher BES concentration (up to 200 mM), methanogenesis activity decreased resulting in an increase of homoacetogenic activity, which challenged the performance of the MEC for H2 production.

  7. Laboratory and pilot plant scale study on the electrochemical oxidation of landfill leachate

    Energy Technology Data Exchange (ETDEWEB)

    Anglada, Angela; Urtiaga, Ana M. [Departamento de Ingenieria Quimica y Quimica Inorganica, E.T.S.I.I. y T., Universidad de Cantabria, Avenida de los castros s/n, 39005 Santander (Spain); Ortiz, Inmaculada, E-mail: ortizi@unican.es [Departamento de Ingenieria Quimica y Quimica Inorganica, E.T.S.I.I. y T., Universidad de Cantabria, Avenida de los castros s/n, 39005 Santander (Spain)

    2010-09-15

    Kinetic data regarding COD oxidation were measured in a laboratory scale cell and used to scale-up an electro-oxidation process for landfill leachate treatment by means of boron-doped diamond anodes. A pilot-scale reactor with a total BDD anode area of 1.05 m{sup 2} was designed. Different electrode gaps in the laboratory and pilot plant cells resulted in dissimilar reactor hydrodynamics. Consequently, generalised dimensionless correlations concerning mass transfer were developed in order to define the mass transfer conditions in both electrochemical systems. These correlations were then used in the design equations to validate the scale-up procedure. A series of experiments with biologically pre-treated landfill leachate were done to accomplish this goal. The evolution of ammonia and COD concentration could be well predicted.

  8. Development of 2D dynamic model for hydrogen-fed and methane-fed solid oxide fuel cells

    Science.gov (United States)

    Luo, X. J.; Fong, K. F.

    2016-10-01

    A new two-dimensional (2D) dynamic model is developed in Fortran to study the mass and energy transport, the velocity field and the electrochemical phenomena of high-temperature solid oxide fuel cell (SOFC). The key feature of this model is that gas properties, reaction heat, open circuit voltage, ohmic voltage and exchange current density are temperature-dependent. Based on this, the change of gas temperature and related characteristics can be evaluated in this study. The transient performances of SOFC, like heat-up and start-up processes, are therefore assessed accordingly. In this 2D dynamic SOFC model, chemical and electrochemical reaction, flow field, mass and energy transfer models are coupled in order to determine the current density, the mass fraction and the temperature of gas species. Mass, momentum and energy balance equations are discretized by finite difference method. Performance evaluation in current density, electrical efficiency and overall efficiency is conducted for the effects of different operating parameters in SOFC. The present model can serve as a valuable tool for in-depth performance evaluation of other design and operating parameters of SOFC unit, as well as further dynamic simulation and optimization of SOFC as a prime mover in cogeneration or trigeneration system.

  9. Investigation of sulfur interactions on a conventional nickel-based solid oxide fuel cell anode during methane steam and dry reforming

    Science.gov (United States)

    Jablonski, Whitney S.

    Solid oxide fuel cells (SOFC) are an attractive energy source because they do not have undesirable emissions, are scalable, and are feedstock flexible, which means they can operate using a variety of fuel mixtures containing H2 and hydrocarbons. In terms of fuel flexibility, most potential fuel sources contain sulfur species, which severely poison the nickel-based anode. The main objective of this thesis is to systematically evaluate sulfur interactions on a conventional Ni/YSZ anode and compare sulfur poisoning during methane steam and dry reforming (SMR and DMR) to a conventional catalyst (Sud Chemie, Ni/K2O-CaAl2O4). Reforming experiments (SMR and DMR) were carried out in a packed bed reactor (PBR), and it was demonstrated that Ni/YSZ is much more sensitive to sulfur poisoning than Ni/K2O-CaAl2O4 as evidenced by the decline in activity to zero in under an hour for both SMR and DMR. Adsorption and desorption of H2S and SO2 on both catalysts was evaluated, and despite the low amount of accessible nickel on Ni/YSZ (14 times lower than Ni/K2O-CaAl2O4), it adsorbs 20 times more H2S and 50 times more SO2 than Ni/K 2O-CaAl2O4. A one-dimensional, steady state PBR model (DetchemPBED) was used to evaluate SMR and DMR under poisoning conditions using the Deutschmann mechanism and a recently published sulfur sub-mechanism. To fit the observed deactivation in the presence of 1 ppm H2S, the adsorption/desorption equilibrium constant was increased by a factor 16,000 for Ni/YSZ and 96 for Ni/K2O-CaAl2O4. A tubular SAE reactor was designed and fabricated for evaluating DMR in a reactor that mimics an SOFC. Evidence of hydrogen diffusion through a supposedly impermeable layer indicated that the tubular SAE reactor has a major flaw in which gases diffuse to unintended parts of the tube. It was also found to be extremely susceptible to coking which leads to cell failure even in operating regions that mimic real biogas. These problems made it impossible to validate the tubular SAE

  10. Biogeochemical aspects of atmospheric methane

    OpenAIRE

    Cicerone, RJ; Oremland, RS

    1988-01-01

    Methane is the most abundant organic chemical in Earth's atmosphere, and its concentration is increasing with time, as a variety of independent measurements have shown. Photochemical reactions oxidize methane in the atmosphere; through these reactions, methane exerts strong influence over the chemistry of the troposphere and the stratosphere and many species including ozone, hydroxyl radicals, and carbon monoxide. Also, through its infrared absorption spectrum, methane is an important greenho...

  11. Direct Activation Of Methane

    KAUST Repository

    Basset, Jean-Marie

    2013-07-15

    Heteropolyacids (HPAs) can activate methane at ambient temperature (e.g., 20.degree. C.) and atmospheric pressure, and transform methane to acetic acid, in the absence of any noble metal such as Pd). The HPAs can be, for example, those with Keggin structure: H.sub.4SiW.sub.12O.sub.40, H.sub.3PW.sub.12O.sub.40, H.sub.4SiMo.sub.12O.sub.40, or H.sub.3PMo.sub.12O.sub.40, can be when supported on silica.

  12. In situ High-pressure NMR Observations on the Formation and Dissociation of Methane Hydrate

    Institute of Scientific and Technical Information of China (English)

    Ai Bing CHEN; Wei Ping ZHANG; Xi Jie LAN; Heng ZHENG; Xiu Mei LIU; Xiu Wen HAN; Xin He BAO

    2006-01-01

    A home-made static NMR cell with pressure up to 10 MPa was employed to observe the formation and dissociation processes of methane hydrate by in situ 1H and 13C NMR spectroscopies. Methane hydrate can be formed or decomposed in the temperature range of -5 to-13℃ at pressures between 4.0 and 7.0 MPa. The higher methane pressure, the formation or dissociation temperature of methane hydrate was higher. In situ 1H NMR experiments indicated that the critical size of the hydrate clusters is crucial for the formation of methane hydrate.

  13. Toward highly efficient in situ dry reforming of H2S contaminated methane in solid oxide fuel cells via incorporating a coke/sulfur resistant bimetallic catalyst layer

    NARCIS (Netherlands)

    Hua, B.; Yan, N.; Li, M.; Sun, Y.-F.; Chen, J.; Zhang, Y.-Q.; Li, J.; Etsell, T.; Sarkar, P.; Luo, J.L.

    2016-01-01

    The escalating global warming effects are a reason for immediate measures to reduce the level of greenhouse gases. In this context, dry reforming of methane (DRM), an old yet both scientifically and industrially important process, is making a comeback in contributing to the utilization of CO2. Howev

  14. STATE OF THE PRACTICE FOR BIOREACTOR LANDFILLS - SUMMARY OF USEPA WORKSHOP ON BIOREACTOR LANDFILLS: SUMMARY

    Science.gov (United States)

    This is a summary of the Workshop on Landfill Bioreactors, held 9/6-7/2000 in Arlington, VA. The purpose of the workshop was to provide a forum to EPA, state and local governments, solid waste industry, and academic research representatives to exchange information and ideas on b...

  15. Evaluating Bay Area Methane Emission Inventory

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Marc [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Jeong, Seongeun [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-03-01

    As a regulatory agency, evaluating and improving estimates of methane (CH4) emissions from the San Francisco Bay Area is an area of interest to the Bay Area Air Quality Management District (BAAQMD). Currently, regional, state, and federal agencies generally estimate methane emissions using bottom-up inventory methods that rely on a combination of activity data, emission factors, biogeochemical models and other information. Recent atmospheric top-down measurement estimates of methane emissions for the US as a whole (e.g., Miller et al., 2013) and in California (e.g., Jeong et al., 2013; Peischl et al., 2013) have shown inventories underestimate total methane emissions by ~ 50% in many areas of California, including the SF Bay Area (Fairley and Fischer, 2015). The goal of this research is to provide information to help improve methane emission estimates for the San Francisco Bay Area. The research effort builds upon our previous work that produced methane emission maps for each of the major source sectors as part of the California Greenhouse Gas Emissions Measurement (CALGEM) project (http://calgem.lbl.gov/prior_emission.html; Jeong et al., 2012; Jeong et al., 2013; Jeong et al., 2014). Working with BAAQMD, we evaluate the existing inventory in light of recently published literature and revise the CALGEM CH4 emission maps to provide better specificity for BAAQMD. We also suggest further research that will improve emission estimates. To accomplish the goals, we reviewed the current BAAQMD inventory, and compared its method with those from the state inventory from the California Air Resources Board (CARB), the CALGEM inventory, and recent published literature. We also updated activity data (e.g., livestock statistics) to reflect recent changes and to better represent spatial information. Then, we produced spatially explicit CH4 emission estimates on the 1-km modeling grid used by BAAQMD. We present the detailed activity data, methods and derived emission maps by sector

  16. COMMERCIAL-SCALE AEROBIC-ANAEROBIC BIOREACTOR LANDFILL OPERATIONS

    Science.gov (United States)

    A sequential aerobic-anaerobic treatment system has been applied at a commercial scale (3,000 ton per day) municipal solid waste landfill in Kentucky, USA since 2001. In this system, the uppermost layer of landfilled waste is aerated and liquid waste including leachate, surface w...

  17. Composition of leachate from old landfills in Denmark

    DEFF Research Database (Denmark)

    Kjeldsen, Peter; Christophersen, Mette

    2001-01-01

    smaller landfills by a comprehensive review of the investigations carried out by the counties. In total 106 landfills were selected by criteria avoiding dilution effects. A database was constructed using a standard program. Statistical evaluations showed that the leachate concentrations in general...

  18. Quantification of long term emission potential from landfills

    NARCIS (Netherlands)

    Heimovaara, T.J.

    2011-01-01

    Novel approaches for the after-care of Municipal Solid Waste (MSW) landfills are based on technological measures to reduce the long term emission potential in a short time period. Biological degradation in landfills is a means to significantly reduce the long term emission potential. Leachate emissi

  19. Characterization and treatment of municipal landfill leachates

    Energy Technology Data Exchange (ETDEWEB)

    Welander, Ulrika

    1998-03-01

    The efficiency of different leachate treatment methods for the removal of refractory organic compounds and ammonium-nitrogen was investigated. The methods evaluated were nitrification, denitrification, adsorption onto activated carbon, precipitation by ferric chloride or aluminum sulphate and oxidation by ozone or Fenton`s reagent. Furthermore, analyses were performed on leachates from municipal landfills of different kinds (a biocell deposit, a conventional mixed landfill containing household and industrial waste, and an ash deposit) in order to study the leachate composition in regard to various hydrophobic organic compounds as a function of the type of waste deposited. The results suggested that, in order to achieve a satisfactory removal of both ammonium-nitrogen and organic substances, the treatment of methanogenic leachates should be performed through a process combining biological and physical or chemical stages. When the biological treatment was not combined with a physical or a chemical process a COD removal of only 20-30% was achieved, whereas the toxicity of the leachate was significantly reduced. In contrast, a combination of nitrification and either adsorption onto activated carbon or oxidation using Fenton`s reagent resulted in a COD removal of about 80%, although certain specific organic compounds, such as phthalates, were unaffected by the treatment. A combination of nitrification, precipitation by ferric chloride and adsorption onto activated carbon removed 96% of the TOC. The analyses of leachates from municipal landfills of different types showed the leachate from the ash deposit to contain more C4-substituted phenols than the other leachates and to likewise contain alkanes, which the others did not 154 refs, 12 figs, 4 tabs

  20. Landfill energy complex based on the renewable energy installations

    Science.gov (United States)

    Gilmanshin, Iskander; Kashapov, Nail; Gilmanshina, Suriya; Galeeva, Asiya

    2016-06-01

    The article presents the analysis of standard approaches to degassing of landfills. The need of comprehensive work on the degassing of the landfill body is identified. The author's task decomposition of the landfill degassing is formulated. The analysis of existing methods of work on degassing of landfills is presented. The author's approach is including implements of series of parallel studies in the framework of achieving a common goal to reduce the anthropogenic pressure on the ecosystem of the region due to the need for disposal of solid waste. An action plan for the development of the target problem-oriented management techniques of the landfill with the following development of the effective energy complex is formulated.

  1. Latent methane in fossil coals

    Energy Technology Data Exchange (ETDEWEB)

    A.D. Alexeev; E.V. Ulyanova; G.P. Starikov; N.N. Kovriga [Academy of Sciences of Ukraine, Donetsk (Ukraine). Institute for Physics of Mining Processes

    2004-07-01

    It is established experimentally using 1H NMR wide line spectroscopy that methane can exist in coals not only in open or closed porosity and fracture systems but also in solid solutions in coal substance, in particular, under methane pressure 2 MPa or higher. Methane dissolved in coal minerals reversibly modifies their lattice parameters as determined from X-ray diffraction analysis. Co-existence of these methane forms in fossil coals causes multi-step desorption kinetics. It is shown experimentally that the long-term latent methane desorption is effected mainly by closed porosity, which in turn is determined by coal rank. 21 refs., 3 figs., 2 tabs.

  2. Estimating methane emissions from biological and fossil-fuel sources in the San Francisco Bay Area

    Science.gov (United States)

    Jeong, Seongeun; Cui, Xinguang; Blake, Donald R.; Miller, Ben; Montzka, Stephen A.; Andrews, Arlyn; Guha, Abhinav; Martien, Philip; Bambha, Ray P.; LaFranchi, Brian; Michelsen, Hope A.; Clements, Craig B.; Glaize, Pierre; Fischer, Marc L.

    2017-01-01

    We present the first sector-specific analysis of methane (CH4) emissions from the San Francisco Bay Area (SFBA) using CH4 and volatile organic compound (VOC) measurements from six sites during September - December 2015. We apply a hierarchical Bayesian inversion to separate the biological from fossil-fuel (natural gas and petroleum) sources using the measurements of CH4 and selected VOCs, a source-specific 1 km CH4 emission model, and an atmospheric transport model. We estimate that SFBA CH4 emissions are 166-289 Gg CH4/yr (at 95% confidence), 1.3-2.3 times higher than a recent inventory with much of the underestimation from landfill. Including the VOCs, 82 ± 27% of total posterior median CH4 emissions are biological and 17 ± 3% fossil fuel, where landfill and natural gas dominate the biological and fossil-fuel CH4 of prior emissions, respectively.

  3. 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.

  4. Methane emissions from grasslands.

    NARCIS (Netherlands)

    Pol-van Dasselaar, van den A.

    1998-01-01

    IntroductionMethane (CH 4 ) is an important greenhouse gas. The concentration of greenhouse gases in the atmosphere has been increasing since pre-industrial times, mainly due to human activities. This increase gives concern, because it may cause global warming due to an enhanced greenhous

  5. Terrestrial plant methane production

    DEFF Research Database (Denmark)

    Mikkelsen, Teis Nørgaard; Bruhn, Dan; Møller, Ian M.

    We evaluate all experimental work published on the phenomenon of aerobic methane (CH4) generation in terrestrial plants. We conclude that the phenomenon is true. Four stimulating factors have been observed to induce aerobic plant CH4 production, i.e. cutting injuries, increasing temperature...

  6. Methane and trichloroethylene oxidation by an estuarine methanotroph, Methylobacter sp. strain BB5.1.

    OpenAIRE

    Smith, K. S.; Costello, A. M.; Lidstrom, M E

    1997-01-01

    An estuarine methanotroph was isolated from sediment enrichments and designated Methylobacter sp. strain BB5.1. In cells grown on medium with added copper, oxidation of methane and trichloroethylene occurred with similar Ks values, but the Vmax for trichloroethylene oxidation was only 0.1% of the methane oxidation Vmax. Cells grown on low-copper medium did not oxidize trichloroethylene and showed a variable rate of methane oxidation.

  7. Another Source of Atmospheric Methane

    Institute of Scientific and Technical Information of China (English)

    于心科

    1997-01-01

    The atmospheric concentration of methane is steadily increasin.Lacking of precise estimates of source and sink strengths for the atmospheric methane severely limits the current understanding of the global methane cycle.Agood budget of atmospheric methane can enhance our understanding of the global carbon cycle and global climate change,The known estimates of the main source and sink strengths are gresented in this paper,In terms of carbon isotopic studies,it is evidenced that the earth's primodial methane,which was trapped in the earth during its formation,may be another source of methane,with extensive,earth's degassing which is calleld the "breathing" process of the earth and played an important role in the formation of the promitive atmosphere,large amounts of methane were carried from the deep interior to the surface and then found its way into the atmosphere.

  8. Methane capture from livestock manure.

    Science.gov (United States)

    Tauseef, S M; Premalatha, M; Abbasi, Tasneem; Abbasi, S A

    2013-03-15

    It has been estimated that livestock manure contributes about 240 million metric tons of carbon dioxide equivalent of methane to the atmosphere and represents one of the biggest anthropogenic sources of methane. Considering that methane is the second biggest contributor to global warming after carbon dioxide, it is imperative that ways and means are developed to capture as much of the anthropogenic methane as possible. There is a major associated advantage of methane capture: its use as a source of energy which is comparable in 'cleanness' to natural gas. The present review dwells upon the traditional ways of methane capture used in India, China, and other developing countries for providing energy to the rural poor. It then reviews the present status of methane capture from livestock manure in developed countries and touches upon the prevalent trends.

  9. [The Trace Methane Sensor Based on TDLAS-WMS].

    Science.gov (United States)

    Liu, Yang; Wu, Jia-nan; Chen, Mei-mei; Yang, Xin-hua; Chen, Chen

    2016-01-01

    Methane is a colorless, odorless, flammable and explosive gas, which not only is the cause to induce significant security risk in coal mining operation, but also one of the important greenhouse gases, so the monitoring of methane is extremely critical. A trace methane gas sensor is designed and developed using the combination of tunable diode laser absorption spectroscopy (TDLAS) and wavelength modulation spectroscopy (WMS) detection technology, which is based on the methane R(3) absorption branch in 2v3 second harmonic band. Through tuning parameters -0.591 cm(-1) x K(-1), using the method that change the working temperature of distributed feedback (DFB) laser to obtain the best absorption wavelength of methane at 1.654 μm. When the mid-wavelength of DFB laser is selected, the appropriate emitting intension can be obtained via adjusting the amplitude of inject current of DFB laser. Meanwhile, combining the frequency modulation technology to move the bandwidth of detection signal from low frequency to high frequency to reduce the 1/f noise. With aspect to the optical structure, utilizing herriott cell with 76 m effective optical path to guarantee the detection of trace methane is successful. Utilizing the proposed trace methane sensor to extract the second harmonic signal of detected methane in the range of 50 to 5 000 μmol x mol(-1), and adopting minimum mean square error criterion to fit the relationship between methane concentration and signal noise ratio, harmonic peak signal and methane concentration, respectively. In addition, the minimum detection limit is 1.4 μmol x mol(-1). The experiment results show the symmetry of harmonic waveform is good, no intensity modulation, and the factor of intensity-modulated impacts on harmonic detection is eliminated.

  10. Field test of infrared thermography applied to biogas controlling in landfill sites

    Science.gov (United States)

    Madruga, Francisco J.; Muñoz, Jaime M.; González, Daniel A.; Tejero, Juan I.; Cobo, Adolfo; Gil, José L.; Conde, Olga M.; López-Higuera, Jose M.

    2007-04-01

    The gases accumulated inside the landfill as result of the fermentation of Municipal Solid Waste (MSW) known as biogas, are taking into consideration all possible uses as direct transformation into electricity. The system for collecting, regulating and controlling the biogas must include all the necessary safety features where the biogas leakage presents a high impact. Infrared thermography can be use to detect gas leakages due to the differences in temperature between the gas and the immediate surroundings. This method is able to monitor a wide area of landfill sites, quickly. This technology will not be effective if the differences in temperature are not better than five degrees. This paper describes a field test conducted to study the limitations of the infrared thermography caused by weather conditions and the moment of day or/and season when the thermal images was captured. Pipelines, borders, cells, covers, slopes and leakage (hot spots) are studied and optimum conditions are defined.

  11. 40 CFR 60.752 - Standards for air emissions from municipal solid waste landfills.

    Science.gov (United States)

    2010-07-01

    ... municipal solid waste landfills. 60.752 Section 60.752 Protection of Environment ENVIRONMENTAL PROTECTION... of Performance for Municipal Solid Waste Landfills § 60.752 Standards for air emissions from municipal solid waste landfills. (a) Each owner or operator of an MSW landfill having a design capacity...

  12. Industrial Waste Landfill IV upgrade package

    Energy Technology Data Exchange (ETDEWEB)

    1994-03-29

    The Y-12 Plant, K-25 Site, and ORNL are managed by DOE`s Operating Contractor (OC), Martin Marietta Energy Systems, Inc. (Energy Systems) for DOE. Operation associated with the facilities by the Operating Contractor and subcontractors, DOE contractors and the DOE Federal Building result in the generation of industrial solid wastes as well as construction/demolition wastes. Due to the waste streams mentioned, the Y-12 Industrial Waste Landfill IV (IWLF-IV) was developed for the disposal of solid industrial waste in accordance to Rule 1200-1-7, Regulations Governing Solid Waste Processing and Disposal in Tennessee. This revised operating document is a part of a request for modification to the existing Y-12 IWLF-IV to comply with revised regulation (Rule Chapters 1200-1-7-.01 through 1200-1-7-.08) in order to provide future disposal space for the ORR, Subcontractors, and the DOE Federal Building. This revised operating manual also reflects approved modifications that have been made over the years since the original landfill permit approval. The drawings referred to in this manual are included in Drawings section of the package. IWLF-IV is a Tennessee Department of Environmental and Conservation/Division of Solid Waste Management (TDEC/DSWM) Class 11 disposal unit.

  13. Recent decreases in fossil-fuel emissions of ethane and methane derived from firn air.

    Science.gov (United States)

    Aydin, Murat; Verhulst, Kristal R; Saltzman, Eric S; Battle, Mark O; Montzka, Stephen A; Blake, Donald R; Tang, Qi; Prather, Michael J

    2011-08-10

    Methane and ethane are the most abundant hydrocarbons in the atmosphere and they affect both atmospheric chemistry and climate. Both gases are emitted from fossil fuels and biomass burning, whereas methane (CH(4)) alone has large sources from wetlands, agriculture, landfills and waste water. Here we use measurements in firn (perennial snowpack) air from Greenland and Antarctica to reconstruct the atmospheric variability of ethane (C(2)H(6)) during the twentieth century. Ethane levels rose from early in the century until the 1980s, when the trend reversed, with a period of decline over the next 20 years. We find that this variability was primarily driven by changes in ethane emissions from fossil fuels; these emissions peaked in the 1960s and 1970s at 14-16 teragrams per year (1 Tg = 10(12) g) and dropped to 8-10 Tg  yr(-1) by the turn of the century. The reduction in fossil-fuel sources is probably related to changes in light hydrocarbon emissions associated with petroleum production and use. The ethane-based fossil-fuel emission history is strikingly different from bottom-up estimates of methane emissions from fossil-fuel use, and implies that the fossil-fuel source of methane started to decline in the 1980s and probably caused the late twentieth century slow-down in the growth rate of atmospheric methane.

  14. Qualitative assessment of methane emission inventory from municipal solid waste disposal sites: a case study

    Science.gov (United States)

    Kumar, Sunil; Mondal, A. N.; Gaikwad, S. A.; Devotta, Sukumar; Singh, R. N.

    2004-09-01

    In developing countries like India, urban solid waste (SW) generation is increasing enormously and most of the SWs are disposed off by land filling in low-lying areas, resulting into generation of large quantities of biogas. Methane, the major constituent gas is known to cause global warming due to green house gas (GHG) effect. There is a need to study the ever-increasing contribution of SW to the global GHG effect. To assess the impacts, estimation of GHG emission is must and to avoid misguidance by these emission-data, qualitative assessment of the estimated GHG is a must. In this paper, methane emission is estimated for a particular landfill site, using default methodology and modified triangular methodology. Total methane generation is same for both theoretical methodologies, but the modified triangular method has an upper hand as it provides a time-dependent emission profile that reflects the true pattern of the degradation process. To check the quality of calculated emission-data, extensive sampling is carried out for different seasons in a year. Field results show a different trend as compared to theoretical results, this compels for logical thinking. Each methane emission-data is backed up by the uncertainty associated with it, this further strengthens the quality check of these data. Uncertainty calculation is done using Monte Carlo simulation technique, recommended in IPCC Guideline. In the due course of qualitative assessment of methane emission-data, many site-specific sensitive parameters are discovered and are briefly discussed in this paper.

  15. Accurate fit and thermochemical analysis of the adsorption isotherms of methane in zeolite 13X

    Energy Technology Data Exchange (ETDEWEB)

    Llano-Restrepo, M. [University of Valle, Valle (Colombia). School of Chemical Engineering

    2010-07-01

    The recovery of methane from landfill gases and coal mines has become of the utmost importance because methane has a global-climate warming potential much higher than that of carbon dioxide. Zeolite 13X is widely used for the separation of methane and carbon dioxide from such sources. Accurate fits of the adsorption isotherms of methane in zeolite 13X are required for the rigorous simulation of that separation. In this work, a generalized statistical thermodynamic adsorption (GSTA) model has been used to obtain a very accurate correlation of a published set of adsorption isotherms of methane in zeolite 13X that were measured from 120 K to 273 K over the pressure range 0.07 Pa to 12.2 MPa. In contrast, none of five traditional adsorption models was capable of fitting these isotherms. A thermochemical interpretation of the correlation is provided and predictions for the isosteric heat of adsorption are made, which turn out to be in excellent agreement with the available experimental data.

  16. A laboratory-scale comparison of compost and sand--compost--perlite as methane-oxidizing biofilter media.

    Science.gov (United States)

    Philopoulos, Andrew; Ruck, Juliane; McCartney, Daryl; Felske, Christian

    2009-03-01

    Municipal solid waste landfills produce methane, a potent greenhouse gas. A treatment approach is to passively vent landfill gas through a methane-oxidizing biofilter medium, a porous substrate that facilitates the growth of methanotrophic bacteria. Two substrates, compost and a sand-compost-perlite (SCP) mixture, were evaluated in a laboratory-scale experiment for their suitability as biofilter media. The SCP mixture was investigated to minimize settlement and was based on a particle size distribution specification used for turf grass. The long-term (218 days) methane removal rates showed that both compost and SCP were capable of removing 100% of the methane influent flux (134 g CH(4) m( -2) day(-1)). The post-experiment analysis showed that compost had compacted more than SCP. This did not affect the results; however, in a field installation, traffic on the biofilter surface (e.g. maintenance) could cause further compaction and negatively affect performance. Exopolymeric substance produced by the methanotrophic bacteria, attributed by others for declining removal rates due to bio-clogging, was not observed to affect the results. The maximum exopolymeric substance values measured were 23.9 and 7.8 mg D-glucose g(-1) (dry basis) for compost and SCP, respectively.

  17. Ecotoxicological assessment and evaluation of a pine bark biosorbent treatment of five landfill leachates.

    Science.gov (United States)

    Ribé, Veronica; Nehrenheim, Emma; Odlare, Monica; Gustavsson, Lillemor; Berglind, Rune; Forsberg, Ake

    2012-10-01

    When selecting a landfill leachate treatment method the contaminant composition of the leachate should be considered in order to obtain the most cost-effective treatment option. In this study the filter material pine bark was evaluated as a treatment for five landfill leachates originating from different cells of the same landfill in Sweden. The objective of the study was to determine the uptake, or release, of metals and dissolved organic carbon (DOC) during a leaching test using the pine bark filter material with the five different landfill leachates. Furthermore the change of toxicity after treatment was studied using a battery of aquatic bioassays assessing luminescent bacteria (Vibrio fischeri) acute toxicity (30-min Microtox®), immobility of the crustacean Daphnia magna, growth inhibition of the algae Pseudokirchneriella subcapitata and the aquatic plant Lemna minor; and genotoxicity with the bacterial Umu-C assay. The results from the toxicity tests and the chemical analysis were analyzed in a Principal Component Analysis and the toxicity of the samples before and after treatment was evaluated in a toxicity classification. The pine bark filter material reduced the concentrations of metal contaminants from the landfill leachates in the study, with some exceptions for Cu and Cd. The Zn uptake of the filter was high for heavily contaminated leachates (≥73%), although some desorption of zinc occurred in less contaminated waters. Some of the leachates may require further treatment due to discharge into a natural recipient in order to reduce the risk of possible biological effects. The difference in pH changes between the different leachates was probably due to variations in buffering capacity, affected by physicochemical properties of the leachate. The greatest desorption of phenol during filtration occurred in leachates with high conductivity or elevated levels of metals or salts. Generally, the toxicity classification of the leachates implies that although

  18. A Portable Laser Photoacoustic Methane Sensor Based on FPGA.

    Science.gov (United States)

    Wang, Jianwei; Wang, Huili; Liu, Xianyong

    2016-09-21

    A portable laser photoacoustic sensor for methane (CH₄) detection based on a field-programmable gate array (FPGA) is reported. A tunable distributed feedback (DFB) diode laser in the 1654 nm wavelength range is used as an excitation source. The photoacoustic signal processing was implemented by a FPGA device. A small resonant photoacoustic cell is designed. The minimum detection limit (1σ) of 10 ppm for methane is demonstrated.

  19. A Portable Laser Photoacoustic Methane Sensor Based on FPGA

    Science.gov (United States)

    Wang, Jianwei; Wang, Huili; Liu, Xianyong

    2016-01-01

    A portable laser photoacoustic sensor for methane (CH4) detection based on a field-programmable gate array (FPGA) is reported. A tunable distributed feedback (DFB) diode laser in the 1654 nm wavelength range is used as an excitation source. The photoacoustic signal processing was implemented by a FPGA device. A small resonant photoacoustic cell is designed. The minimum detection limit (1σ) of 10 ppm for methane is demonstrated. PMID:27657079

  20. Geochemical and VOC-constraints on landfill gas age and attenuation characteristics: A case study from a waste disposal facility in Southern California.

    Science.gov (United States)

    Hagedorn, Benjamin; Kerfoot, Henry B; Verwiel, Mark; Matlock, Bruce

    2016-07-01

    In this study, a multi-tracer approach was applied to a complex, methane-impacted site in Southern California to (1) distinguish between natural gas and landfill gas (LFG)-derived methane impacts at site perimeter gas probes, (2) estimate the relative age of the LFG at these probes, and (3) document natural attenuation trends during a 3-year monitoring period. Relationships between methane and ethane values suggest that at the majority of probes, methane is from LFG and not from natural gas and that the relative contribution of LFG methane at these probes has increased over the monitoring period. To evaluate whether LFG is attenuating in the subsurface, the relative age of LFG was estimated by comparing readily degraded VOCs that are major constituents in LFG (toluene in this case) with those resistant to degradation (Freons). Time-series data trends are consistent with several probes being impacted by fresh LFG from recent releases that occurred after the update of the local LFG collection and control system (LFGCCS). Data further indicate some probes to be only affected by legacy LFG from a past release that occurred prior to the LFGCCS update and that, because of a lack of oxygen in the subsurface, had not been fully degraded. The outlined attenuation evaluation methodology is potentially applicable to other sites or even groundwater contaminants; however, the assessment is limited by the degree of homogeneity of the LFG source composition and non-LFG-derived toluene inputs to the analyzed samples.

  1. Biodegradability potential of two experimental landfills in Brazil Potencial de biodegrabilidade de dois aterros sanitários experimentais no Brasil

    Directory of Open Access Journals (Sweden)

    Rosana Filomena Vazoller

    2001-06-01

    Full Text Available Solid wastes anaerobic biodegradability, methane production potential and microbiological composition of two experimental sanitary landfills in Brazil, running for one year, were evaluated. The two landfills showed a similar organic matter stabilization during the methane production phase, despite the high heterogeneity of the solid wastes. Both landfills presented the same level of methane (around 91.5 L CH4 / kg Volatile Total Solids and organic acids, mainly acetic and butyric acids, in the leachate. Bacterial isolates belonged to genera Megasphaera, Selenomonas, Methanobacterium, Methanobrevibacter and Methanosarcina.Durante um ano foi realizado o monitoramento da biodegradabilidade anaeróbia de resíduos sólidos, do potencial de geração de metano e da composição microbiológica de dois aterros sanitários experimentais. Observou-se que, apesar da grande heterogeneidade dos resíduos sólidos, os resultados em termos de estabilização de matéria orgânica durante a fase de produção de metano foram similares para os dois aterros. Ambos os sistemas apresentaram as mesmas faixas de produção de metano (91.5 L CH4 / kg STV - sólidos totais voláteis e de ácidos orgânicos, principalmente ácidos acético e butírico. Isolou-se ainda, culturas bacterianas dos gêneros Megasphaera, Selenomonas, Methanobacterium, Methanobrevibacter and Methanosarcina.

  2. Sensitivity of detection of fugitive methane emissions from coal seam gas fields

    Science.gov (United States)

    Feitz, A. J.; Berko, H.; Wilson, P.; Jenkins, C.; Loh, Z. M.; Etheridge, D.

    2013-12-01

    There is increasing recognition that minimising methane emissions from the oil and gas sector is a key step in reducing global greenhouse gas emissions in the near term. Atmospheric monitoring techniques are likely to play an important future role in measuring the extent of existing emissions and verifying emission reductions. They can be very suitable for monitoring gas fields as they are continuous and integrate emissions from a number of potential point and diffuse sources that may vary in time. Geoscience Australia and CSIRO Marine & Atmospheric Research have collected three years of continuous methane and carbon dioxide measurements at their atmospheric composition monitoring station ('Arcturus') in the Bowen Basin, Australia. Methane signals in the Bowen Basin are likely to be influenced by cattle production, landfill, coal production, and conventional and coal seam gas (CSG) production. Australian CSG is typically 'dry' and is characterised by a mixed thermogenic-biogenic methane source with an absence of C3-C6+ alkanes. The range of δ13C isotopic signatures of the CSG is similar to methane from landfill gas and cattle emissions. The absence of standard in-situ tracers for CSG fugitive emissions suggests that having a comprehensive baseline will be critical for successful measurement of fugitive emissions using atmospheric techniques. In this paper we report on the sensitivity of atmospheric techniques for the detection of fugitive emissions from a simulated new CSG field against a three year baseline signal. Simulation of emissions was performed for a 1-year period using the coupled prognostic meteorological and air pollution model TAPM at different fugitive emission rates (i.e. estimates of <1% to up to 10% of production lost) and distances (i.e. 10 - 50 km) from the station. Emissions from the simulated CSG field are based on well density, production volumes, and field size typical of CSG fields in Australia. The distributions of the perturbed and

  3. Bacterial community diversity in municipal waste landfill sites.

    Science.gov (United States)

    Song, Liyan; Wang, Yangqing; Tang, Wei; Lei, Yu

    2015-09-01

    Little is known about the bacterial diversity of landfills and how environmental factors impact the diversity. In this study, PCR-based 454 pyrosequencing was used to investigate the bacterial communities of ten landfill leachate samples from five landfill sites in China. A total of 137 K useable sequences from the V3-V6 regions of the 16S rRNA gene were retrieved from 205 K reads. These sequences revealed the presence of a large number of operational taxonomic units (OTUs) in the landfills (709-1599 OTUs per sample). The most predominant bacterial representatives in the landfills investigated, regardless of geographic area, included Gammaproteobacteria, Firmicutes, and Bacteroidetes. The phyla Fusobacteria and Tenericutes were also found for the first time to be predominant in the landfills. The phylum Fusobacteria predominated (51.5 and 48.8%) in two semi-arid landfills, and the phylum Tenericutes dominated (30.6%) at one humid, subtropical landfill. Further, a large number of Pseudomonas was detected in most samples, comprising the dominant group and accounting for 40.9 to 92.4% of the total abundance. Principal component analysis (PCA) and cluster analysis based on OTU abundance showed that the abundant taxa separated the bacterial community. Canonical correlation analysis (CCA) suggested that precipitation and landfilling age significantly impact on the bacterial community structure. The bacterial community function (e.g., cellulolytic bacteria, sulfate-reducing bacteria (SRB), sulfate-oxidizing bacteria, and xenobiotic organic compound (XOC)-degrading bacteria) was also diverse, but the pattern is unclear.

  4. Integrated modeling and up-scaling of landfill processes and heterogeneity using stochastic approach

    OpenAIRE

    Bun, A.; Heimovaara, T.J.; Baviskar, S.M.; Van Turnhout, A.G.; Konstantaki, L.A.

    2012-01-01

    Municipal solid waste landfills are a very complex and heterogeneous systems. The waste in a landfill body is a heterogeneous mixture of a wide range of materials containing high levels of organic matter, high amounts of salts and a wide range of different organic and inorganic substances, such as heavy metals and organic solvents. A range of processes of different nature occur within landfills. Bio-geochemical processes in a landfill body lead to the development of landfill gases, a mixture ...

  5. 垃圾填埋场甲烷释放及氧化技术研究进展%Research Progress on CH4 Emissions and Oxidation Process in the Landfill

    Institute of Scientific and Technical Information of China (English)

    聂发辉; 周永希; 张后虎; 赵克强; 蔡邦成; 赵泽华

    2016-01-01

    垃圾填埋场作为人类活动最大的甲烷( CH4)释放源,其大量释放导致全球温室效应日益加剧。因此甲烷排放和控制技术的基础研究对缓解温室效应意义重大。从甲烷氧化研究进展、垃圾处理现状和垃圾填埋场甲烷释放影响因素等方面对国内外研究进展进行综述。研究表明:甲烷好氧氧化已经形成了完整的研究体系,而硫酸盐还原型( SAMO)及反硝化型甲烷厌氧氧化( DAMO)原理亟待研究。垃圾填埋场甲烷的产生受垃圾组分、含水率、温度以及pH等因素影响。控制影响因素,综合利用经济可行的减排策略是今后研究的主要方向。%Global warming has become increasingly worse mainly due to the release of greenhouse gases.Since landfills are the largest sources of anthropogenic CH4 emissions, the basic research on the mitigation of landfill CH4 emissions is of great significance.The research progress of methane oxidation, the status of waste treatment and the influential factors of landfill methane release were summarized.It is shown that aerobic oxidation of landfill CH4 has been extensively explored and the principles of sulphate-dependent anaerobic methane oxidation ( SAMO ) and nitrite-dependent anaerobic methane oxidation ( DAMO) should be further studied.Landfill CH4 generation and emission was influenced by garbage composition, moisture content, temperature and pH, etc.The main research direction on landfill CH4 in the future will be to control the influential factors and to utilize the economical feasible strategies of carbon emission reduction.

  6. Clumped isotope effects during OH and Cl oxidation of methane

    Science.gov (United States)

    Whitehill, Andrew R.; Joelsson, Lars Magnus T.; Schmidt, Johan A.; Wang, David T.; Johnson, Matthew S.; Ono, Shuhei

    2017-01-01

    A series of experiments were carried out to determine the clumped (13CH3D) methane kinetic isotope effects during oxidation of methane by OH and Cl radicals, the major sink reactions for atmospheric methane. Experiments were performed in a 100 L quartz photochemical reactor, in which OH was produced from the reaction of O(1D) (from O3 photolysis) with H2O, and Cl was from photolysis of Cl2. Samples were taken from the reaction cell and analyzed for methane (12CH4, 12CH3D, 13CH4, 13CH3D) isotopologue ratios using tunable infrared laser direct absorption spectroscopy. Measured kinetic isotope effects for singly substituted species were consistent with previous experimental studies. For doubly substituted methane, 13CH3D, the observed kinetic isotope effects closely follow the product of the kinetic isotope effects for the 13C and deuterium substituted species (i.e., 13,2KIE = 13KIE × 2KIE). The deviation from this relationship is 0.3‰ ± 1.2‰ and 3.5‰ ± 0.7‰ for OH and Cl oxidation, respectively. This is consistent with model calculations performed using quantum chemistry and transition state theory. The OH and Cl reactions enrich the residual methane in the clumped isotopologue in open system reactions. In a closed system, however, this effect is overtaken by the large D/H isotope effect, which causes the residual methane to become anti-clumped relative to the initial methane. Based on these results, we demonstrate that oxidation of methane by OH, the predominant oxidant for tropospheric methane, will only have a minor (∼0.3‰) impact on the clumped isotope signature (Δ13CH3D, measured as a deviation from a stochastic distribution of isotopes) of tropospheric methane. This paper shows that Δ13CH3D will provide constraints on methane source strengths, and predicts that Δ12CH2D2 can provide information on methane sink strengths.

  7. Methane oxidation at low temperatures in soil exposed to landfill gas

    DEFF Research Database (Denmark)

    Christophersen, Mette; Linderød, L.; Jensen, Pernille Erland;

    2000-01-01

    moisture content. Soil moisture was the most important factor. However, high Q(10) values indicate that temperature also was important. The four soils tested had optimum soil moisture content between 11 and 32%. At increasing organic matter content, both the optimal soil moisture content and the maximum...

  8. Processes in a compost based landfill biocover; methane emission, transport and oxidation

    DEFF Research Database (Denmark)

    Pedersen, Gitte Bukh

    Metan er en drivhusgas med et potentiale for global opvarmning som er 25 gange større end kuldioxids. Metan produceret i lossepladser kan oxideres i biologiske aktive lossepladsdæklag også kaldet biocover systemer. Denne proces vil kunne reducere lossepladsers bidrag til drivhuseffekten. Den inde...

  9. Quantification of multiple methane emission sources at landfills using a double tracer technique

    DEFF Research Database (Denmark)

    Scheutz, Charlotte; Samuelsson, J.; Fredenslund, Anders Michael;

    2011-01-01

    .5±0.25kg CH4h−1, whereas the carbon dioxide (CO2) and nitrous oxide (N2O) flux was quantified to be in the order of 332±166kg CO2h−1 and 0.06±0.03kg N2Oh−1, respectively. The sludge pit located west of the compost material was quantified to have an emission of 2.4±0.63kgh−1 CH4, and 0.03±0.01kgh−1 N2O....

  10. Use of natural zeolites as a landfill liner.

    Science.gov (United States)

    Tuncan, Ahmet; Tuncan, Mustafa; Koyuncu, Hakan; Guney, Yucel

    2003-02-01

    The purpose of this study is to investigate certain features of a novel material proposed to serve as an impervious liner in landfills. Various ratios of bentonites and zeolites (B/Z) compacted at optimum water content were tested to determine the strength parameters, permeability, pH, heavy metals and other properties. A B/Z ratio of 0.10 was found to be an ideal landfill liner material regarding its low hydraulic conductivity and high cation exchange capacity. The use of B/Z mixtures as an alternative to clay liners would provide potential to significantly reduce the thickness of base liner for landfills.

  11. 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

  12. Are closed landfills free of CH_{4} emissions? A case study of Arico's landfill, Tenerife, Canary Islands

    Science.gov (United States)

    Barrancos, José; Cook, Jenny; Phillips, Victoria; Asensio-Ramos, María; Melián, Gladys; Hernández, Pedro A.; Pérez, Nemesio M.

    2016-04-01

    Landfills are authentic chemical and biological reactors that introduce in the environment a wide amount of gas pollutants (CO2, CH4, volatile organic compounds, etc.) and leachates. Even after years of being closed, a significant amount of landfill gas could be released to the atmosphere through the surface in a diffuse form, also known as non-controlled emission. The study of the spatial-temporal distribution of diffuse emissions provides information of how a landfill degassing takes place. The main objective of this study was to estimate the diffuse uncontrolled emission of CH4 into the atmosphere from the closed Arico's landfill (0.3 km2) in Tenerife Island, Spain. To do so, a non-controlled biogenic gas emission survey of nearly 450 sampling sites was carried out during August 2015. Surface gas sampling and surface landfill CO2 efflux measurements were carried out at each sampling site by means of a portable non-dispersive infrared spectrophotometer (NDIR) model LICOR Li800 following the accumulation chamber method. Landfill gases, CO2 and CH4, were analyzed using a double channel VARIAN 4900 micro-GC. The CH4 efflux was computed combining CO2 efflux and CH4/CO2 ratio in the landfill's surface gas. To quantify the total CH4 emission, CH4 efflux contour map was constructed using sequential Gaussian simulation (sGs) as interpolation method. The total diffuse CH4 emission was estimated in 2.2 t d-1, with CH4 efflux values ranging from 0-922 mg m-2 d-1. This type of studies provides knowledge of how a landfill degasses and serves to public and private entities to establish effective systems for extraction of biogas. This aims not only to achieve higher levels of controlled gas release from landfills resulting in a higher level of energy production but also will contribute to minimize air pollution caused by them.

  13. Landfills, Landfill point locations within Iredell County, NC, Published in 2009, 1:2400 (1in=200ft) scale, Iredell County GIS.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Landfills dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Orthoimagery information as of 2009. It is described as 'Landfill...

  14. Landfills, Landfills - only two in County, Published in 2008, 1:2400 (1in=200ft) scale, Effingham County Board Of Commissioners.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Landfills dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Orthoimagery information as of 2008. It is described as 'Landfills -...

  15. Paper waste - Recycling, incineration or landfilling?

    DEFF Research Database (Denmark)

    Villanueva, Alejandro; Wenzel, Henrik

    2007-01-01

    comparisons of different management options for waste paper. Despite claims of inconsistency, the LCAs reviewed illustrate the environmental benefits in recycling over incineration or landfill options, for paper and cardboard waste. This broad consensus was found despite differences in geographic location......A review of existing life cycle assessments (LCAs) on paper and cardboard waste has been undertaken. The objectives of the review were threefold. Firstly, to see whether a consistent message comes out of published LCA literature on optimum disposal or recycling solutions for this waste type....... Such message has implications for current policy formulation on material recycling and disposal in the EU. Secondly, to identify key methodological issues of paper waste management LCAs, and enlighten the influence of such issues on the conclusions of the LCA studies. Thirdly, in light of the analysis made...

  16. Estimation of emissions of nonmethane organic compounds from a closed landfill site using a landfill gas emission model

    Directory of Open Access Journals (Sweden)

    A. N. Nwachukwu, A. W. Diya

    2013-01-01

    Full Text Available Nonmethane organic compounds (NMOC emissions from landfills often constitute significant risks both to human health and the general environment. To date very little work has been done on tracking the emissions of NMOC from landfills. To this end, a concerted effort was made to investigate the total annual mass emission rate of NMOC from a closed landfill site in South Manchester, United Kingdom. This was done by using field estimates of NMOC concentration and the landfill parameters into the Landfill Gas Emission Model embedded in ACTS and RISK software. Two results were obtained: (i a deterministic outcome of 1.7218 x 10-7 kg/year, which was calculated from mean values of the field estimates of NMOC concentration and the landfill parameters, and (ii a probabilistic outcome of 1.66 x 10-7 - 1.78 x 10-7 kg/year, which is a range of value obtained after Monte Carlo simulation of the uncertain parameters of the landfill including NMOC concentration. A comparison between these two results suggests that the probabilistic outcome is a more representative and reliable estimate of the total annual mass emission of NMOC especially given the variability of the parameters of the model. Moreover, a comparison of the model result and the safety standard of 5.0 x 10-5 kg/year indicate that the mass emission of NMOC from the studied landfill is significantly less than previously thought. However, given that this can accumulate to a dangerous level over a long period of time (such as the age of this landfill site; it may have started affecting the health of the people living within the vicinity of the landfill. A case is therefore made for more studies to be carried out on the emissions of other gases such as CH4 and CO2 from the studied landfill site, as this would help to understand the synergistic effect of the various gases being emitted from the landfill.

  17. Supercritical water oxidation of landfill leachate.

    Science.gov (United States)

    Wang, Shuzhong; Guo, Yang; Chen, Chongming; Zhang, Jie; Gong, Yanmeng; Wang, Yuzhen

    2011-01-01

    In this paper, ammonia as an important ingredient in landfill leachate was mainly studied. Based on Peng-Robinson formulations and Gibbs free energy minimization method, the estimation of equilibrium composition and thermodynamic analysis for supercritical water oxidation of ammonia (SCWO) was made. As equilibrium is reached, ammonia could be totally oxidized in SCW. N(2) is the main product, and the formation of NO(2) and NO could be neglected. The investigation on SCWO of landfill leachate was conducted in a batch reactor at temperature of 380-500 °C, reaction time of 50-300s and pressure of 25 MPa. The effect of reaction parameters such as oxidant equivalent ratio, reaction time and temperature were investigated. The results showed that COD and NH(3) conversion improved as temperature, reaction time and oxygen excess increased. Compared to organics, NH(3) is a refractory compound in supercritical water. The conversion of COD and NH(3) were higher in the presence of MnO(2) than that without catalyst. The interaction between reaction temperature and time was analyzed by using response surface method (RSM) and the results showed that its influence on the NH(3) conversion was relatively insignificant in the case without catalyst. A global power-law rate expression was regressed from experimental data to estimate the reaction rate of NH(3). The activation energy with and without catalyst for NH(3) oxidation were 107.07 ± 8.57 kJ/mol and 83.22 ± 15.62 kJ/mol, respectively.

  18. Syntrophic interactions and mechanisms underpinning anaerobic methane oxidation: targeted metaproteogenomics, single-cell protein detection and quantitative isotope imaging of microbial consortia

    Energy Technology Data Exchange (ETDEWEB)

    Orphan, Victoria Jeanne [California Inst. of Technology (CalTech), Pasadena, CA (United States). Division of Geological and Planetary Sciences

    2014-11-26

    Syntrophy and mutualism play a central role in carbon and nutrient cycling by microorganisms. Yet, our ability to effectively study symbionts in culture has been hindered by the inherent interdependence of syntrophic associations, their dynamic behavior, and their frequent existence at thermodynamic limits. Now solutions to these challenges are emerging in the form of new methodologies. Developing strategies that establish links between the identity of microorganisms and their metabolic potential, as well as techniques that can probe metabolic networks on a scale that captures individual molecule exchange and processing, is at the forefront of microbial ecology. Understanding the interactions between microorganisms on this level, at a resolution previously intractable, will lead to our greater understanding of carbon turnover and microbial community resilience to environmental perturbations. In this project, we studied an enigmatic syntrophic association between uncultured methane-oxidizing archaea and sulfate-reducing bacteria. This environmental archaeal-bacterial partnership represents a globally important sink for methane in anoxic environments. The specific goals of this project were organized into 3 major tasks designed to address questions relating to the ecophysiology of these syntrophic organisms under changing environmental conditions (e.g. different electron acceptors and nutrients), primarily through the development of microanalytical imaging methods which enable the visualization of the spatial distribution of the partners within aggregates, consumption and exchange of isotopically labeled substrates, and expression of targeted proteins identified via metaproteomics. The advanced tool set developed here to collect, correlate, and analyze these high resolution image and isotope-based datasets from methane-oxidizing consortia has the potential to be widely applicable for studying and modeling patterns of activity and interactions across a broad range of

  19. A biological assessment of Wildcat Landfill Superfund Site

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document was prepared as part of the Wildcat Landfill Remedial Investigation (RI) Report; the report was financed through a grant and authority of CERCLA as...

  20. Excavation and characterization of refuse in closed landfill

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Refuse in landfills becomes stabilized as organic matter in refuse degrades and soluble inorganic substances dissolve during their longterm stabilization process.In this paper,this process is also referred to as mineralization process and the resultant stabilized refuse referred to as aged refuse.Aged refuse contains a wide spectrum and huge quantity of microorganisms with strong decomposition capability for refractory organic matter present in some wastewater such as leachate.In this study,aged refuse excavated from 2 to 10 years old closed landfill compartments in Shanghai Refuse Landfill is characterized in terms of particulate distribution by screening,total nitrogen,total phosphorus,biodegradable matter.The approaches for redevelopment of both land and aged refuse in the stabilized landfills are proposed.

  1. LEACHATE CLOGGING ASSESSMENT OF GEOTEXTILE AND SOIL LANDFILL FILTERS

    Science.gov (United States)

    The liquids management strategy for any municipal or hazardous waste landfill requires a knowledgeable design strategy for the leachate collection system located at the base of the waste mass. Such leachate collection systems generally consist of sumps, perforated pipes, drainag...

  2. INVESTIGATION OF HOLOCENE FAULTING PROPOSED C-746-U LANDFILL EXPANSION

    Energy Technology Data Exchange (ETDEWEB)

    Lettis, William [William Lettis & Associates, Inc.

    2006-07-01

    This report presents the findings of a fault hazard investigation for the C-746-U landfill's proposed expansion located at the Department of Energy's (DOE) Paducah Gaseous Diffusion Plant (PGDP), in Paducah, Kentucky. The planned expansion is located directly north of the present-day C-746-U landfill. Previous geophysical studies within the PGDP site vicinity interpret possible northeast-striking faults beneath the proposed landfill expansion, although prior to this investigation the existence, locations, and ages of these inferred faults have not been confirmed through independent subsurface exploration. The purpose of this investigation is to assess whether or not Holocene-active fault displacement is present beneath the footprint of the proposed landfill expansion.

  3. Fuel Flexibility: Landfill Gas Contaminant Mitigation for Power Generation

    Energy Technology Data Exchange (ETDEWEB)

    Storey, John Morse [ORNL; Theiss, Timothy J [ORNL; Kass, Michael D [ORNL; FINNEY, Charles E A [ORNL; Lewis, Samuel [Oak Ridge National Laboratory (ORNL); Kaul, Brian C [ORNL; Besmann, Theodore M [ORNL; Thomas, John F [ORNL; Rogers, Hiram [ORNL; Sepaniak, Michael [University of Tennessee, Knoxville (UTK)

    2014-04-01

    This research project focused on the mitigation of silica damage to engine-based renewable landfill gas energy systems. Characterization of the landfill gas siloxane contamination, combined with characterization of the silica deposits in engines, led to development of two new mitigation strategies. The first involved a novel method for removing the siloxanes and other heavy contaminants from the landfill gas prior to use by the engines. The second strategy sought to interrupt the formation of hard silica deposits in the engine itself, based on inspection of failed landfill gas engine parts. In addition to mitigation, the project had a third task to develop a robust sensor for siloxanes that could be used to control existing and/or future removal processes.

  4. Trends in sustainable landfilling in Malaysia, a developing country.

    Science.gov (United States)

    Fauziah, S H; Agamuthu, P

    2012-07-01

    In Malaysia, landfills are being filled up rapidly due to the current daily generation of approximately 30,000 tonnes of municipal solid waste. This situation creates the crucial need for improved landfilling practices, as sustainable landfilling technology is yet to be achieved here. The objective of this paper is to identify and evaluate the development and trends in landfilling practices in Malaysia. In 1970, the disposal sites in Malaysia were small and prevailing waste disposal practices was mere open-dumping. This network of relatively small dumps, typically located close to population centres, was considered acceptable for a relatively low population of 10 million in Malaysia. In the 1980s, a national programme was developed to manage municipal and industrial wastes more systematically and to reduce adverse environmental impacts. The early 1990s saw the privatization of waste management in many parts of Malaysia, and the establishment of the first sanitary landfills for MSW and an engineered landfill (called 'secure landfill' in Malaysia) for hazardous waste. A public uproar in 2007 due to contamination of a drinking water source from improper landfilling practices led to some significant changes in the government's policy regarding the country's waste management strategy. Parliament passed the Solid Waste and Public Cleansing Management (SWPCM) Act 2007 in August 2007. Even though the Act is yet to be implemented, the government has taken big steps to improve waste management system further. The future of the waste management in Malaysia seems somewhat brighter with a clear waste management policy in place. There is now a foundation upon which to build a sound and sustainble waste management and disposal system in Malaysia.

  5. Ammonia nitrogen desorption from sanitary landfill leachate in filling towers

    OpenAIRE

    Leite,Valderi D.; Barros,Aldre J. M.; Lopes,Wilton S.; Sousa,José T. de

    2014-01-01

    Sanitary landfill leachates present high concentrations of carbonaceous and nitrogenous materials. The crucial point is that carbonaceous materials are of difficult biodegradation, what compromises the performance of biological treatment processes, while nitrogenous materials, such as ammonia nitrogen, probably preclude the use of biological treatments. Therefore, the aim of this work was to study the desorption process of ammonia nitrogen from sanitary landfill leachate in filling towers. De...

  6. A pluridisciplinary model to predict municipal landfill life

    OpenAIRE

    Hiligsmann, Serge; Rodriguez, C.; Lardinois, M.; Radu, Jean-Pol; Charlier, Robert; Destain, Jacqueline; Drion, R.; Thonart, Philippe

    2001-01-01

    Most degradation processes that occur within municipal wastes landfills result from different microbial activities interacting all along the landfill lifetime and that are influenced by several non-biological factors. These complex biological and chemical processes require a multidisciplinary pattern in order to assess and control their environmental impact. Thanks to Walloon Region support, we have developed a pattern or model combining the evolution of different key parameters. Such paramet...

  7. Seismic stability and permanent displacement of landfill along liners

    Institute of Scientific and Technical Information of China (English)

    CHEN YunMin; GAO Deng; ZHU Bin; CHEN RenPeng

    2008-01-01

    The three-part wedge limit equilibrium method for seismic stability analysis of the landfill along liners is presented. The approximate solutions of the factor of safety and the yield acceleration coefficient are obtained. Parametric studies show that the interface strength of liners, the shear strength of waste and the height of retaining wall can influence the seismic stability of landfill along liners. The density and the shear wave velocity of the field waste are obtained by the borehole investigation and the spectral analysis of surface wave (SASW), respectively. The strain-dependent shear modulus and damping ratio of the artifical waste are obtained by the moderate-scale dynamic triaxial tests. The one- dimensional (1D) equivalent linear dynamic response analysis is used to calculate the horizontal equivalent seismic coefficient-time history of the sliding landfill during earthquake. The seismic permanent displacement of the landfill along liners with different site conditons and heights is evaluated by the Newmark method. The catculated results show that ratio of ky/kmax, site conditions, the amplitude and frequency content of the bedrock motion can affect the seismic permanent displacement of the landfill along liners in some degree. Finally, the seismic stability and permanent displacements of three expanded configurations of a certain landfill case are analyzed.

  8. A Decision Making Tool for Hazardous Waste Landfill Site Selection

    Directory of Open Access Journals (Sweden)

    P. Pandiyan

    2011-01-01

    Full Text Available Problem statement: Continuous global environmental crisis and degradation ha