WorldWideScience

Sample records for evaluating carbon dioxide

  1. Evaluating carbon dioxide emissions in international trade of China

    International Nuclear Information System (INIS)

    Lin Boqiang; Sun Chuanwang

    2010-01-01

    China is the world's largest emitter of carbon dioxide (CO 2 ). As exports account for about one-third of China's GDP, the CO 2 emissions are related to not only China's own consumption but also external demand. Using the input-output analysis (IOA), we analyze the embodied CO 2 emissions of China's import and export. Our results show that about 3357 million tons CO 2 emissions were embodied in the exports and the emissions avoided by imports (EAI) were 2333 million tons in 2005. The average contribution to embodied emission factors by electricity generation was over 35%. And that by cement production was about 20%. It implies that the production-based emissions of China are more than the consumption-based emissions, which is evidence that carbon leakage occurs under the current climate policies and international trade rules. In addition to the call for a new global framework to allocate emission responsibilities, China should make great efforts to improve its energy efficiency, carry out electricity pricing reforms and increase renewable energy. In particular, to use advanced technology in cement production will be helpful to China's CO 2 abatement.

  2. Economic Evaluations for the Carbon Dioxide-involved Production of High-value Chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji Hyun; Lee, Dong Woog; Jang, Se Gyu; Kwak, No-Sang; Lee, In Young; Jang, Kyung Ryoung; Shim, Jae-Goo [KEPCO Research Institute, Daejon (Korea, Republic of); Choi, Jong Shin [Korea East-West Power Co. LTD, Seoul (Korea, Republic of)

    2014-06-15

    Economic evaluation of the manufacturing technology of high-value chemicals through the carbonation reaction of carbon dioxide contained in the flue gas was performed, and analysis of the IRR (Internal Rate of Return) and whole profit along the production plan of the final product was conducted. Through a carbonation reaction with sodium hydroxide that is generated from electrolysis and by using carbon dioxide in the combustion gas that is generated in the power plant, it is possible to get a high value products such as sodium bicarbonate compound and also to reduce the carbon dioxide emission simultaneously. The IRR (Internal Rate of Return) and NPV (Net Present Value) methods were used for the economic evaluation of the process which could handle carbon dioxide of 100 tons per day in the period of the 20 years of plant operation. The results of economic evaluation showed that the IRR of baseline case of technology was 67.2% and the profit that obtained during the whole operation period (20 years) was 346,922 million won based on NPV value. When considering ETS due to the emissions trading enforcement that will be activated in 2015, the NPV was improved to a 6,000 million won. Based on this results, it could be concluded that this CO2 carbonation technology is an cost-effective technology option for the reduction of greenhouse gas.

  3. Economic Evaluations for the Carbon Dioxide-involved Production of High-value Chemicals

    International Nuclear Information System (INIS)

    Lee, Ji Hyun; Lee, Dong Woog; Jang, Se Gyu; Kwak, No-Sang; Lee, In Young; Jang, Kyung Ryoung; Shim, Jae-Goo; Choi, Jong Shin

    2014-01-01

    Economic evaluation of the manufacturing technology of high-value chemicals through the carbonation reaction of carbon dioxide contained in the flue gas was performed, and analysis of the IRR (Internal Rate of Return) and whole profit along the production plan of the final product was conducted. Through a carbonation reaction with sodium hydroxide that is generated from electrolysis and by using carbon dioxide in the combustion gas that is generated in the power plant, it is possible to get a high value products such as sodium bicarbonate compound and also to reduce the carbon dioxide emission simultaneously. The IRR (Internal Rate of Return) and NPV (Net Present Value) methods were used for the economic evaluation of the process which could handle carbon dioxide of 100 tons per day in the period of the 20 years of plant operation. The results of economic evaluation showed that the IRR of baseline case of technology was 67.2% and the profit that obtained during the whole operation period (20 years) was 346,922 million won based on NPV value. When considering ETS due to the emissions trading enforcement that will be activated in 2015, the NPV was improved to a 6,000 million won. Based on this results, it could be concluded that this CO2 carbonation technology is an cost-effective technology option for the reduction of greenhouse gas

  4. Evaluating measurements of carbon dioxide emissions using a precision source--A natural gas burner.

    Science.gov (United States)

    Bryant, Rodney; Bundy, Matthew; Zong, Ruowen

    2015-07-01

    A natural gas burner has been used as a precise and accurate source for generating large quantities of carbon dioxide (CO2) to evaluate emissions measurements at near-industrial scale. Two methods for determining carbon dioxide emissions from stationary sources are considered here: predicting emissions based on fuel consumption measurements-predicted emissions measurements, and direct measurement of emissions quantities in the flue gas-direct emissions measurements. Uncertainty for the predicted emissions measurement was estimated at less than 1%. Uncertainty estimates for the direct emissions measurement of carbon dioxide were on the order of ±4%. The relative difference between the direct emissions measurements and the predicted emissions measurements was within the range of the measurement uncertainty, therefore demonstrating good agreement. The study demonstrates how independent methods are used to validate source emissions measurements, while also demonstrating how a fire research facility can be used as a precision test-bed to evaluate and improve carbon dioxide emissions measurements from stationary sources. Fossil-fuel-consuming stationary sources such as electric power plants and industrial facilities account for more than half of the CO2 emissions in the United States. Therefore, accurate emissions measurements from these sources are critical for evaluating efforts to reduce greenhouse gas emissions. This study demonstrates how a surrogate for a stationary source, a fire research facility, can be used to evaluate the accuracy of measurements of CO2 emissions.

  5. Carbon dioxide as chemical feedstock

    National Research Council Canada - National Science Library

    Aresta, M

    2010-01-01

    ... Dioxide as an Inert Solvent for Chemical Syntheses 15 Alessandro Galia and Giuseppe Filardo Introduction 15 Dense Carbon Dioxide as Solvent Medium for Chemical Processes 15 Enzymatic Catalysis in Dense Carbon Dioxide 18 Other Reactions in Dense Carbon Dioxide 19 Polymer Synthesis in Supercritical Carbon Dioxide 20 Chain Polymerizations: Synt...

  6. Carbon dioxide sensor

    Science.gov (United States)

    Dutta, Prabir K [Worthington, OH; Lee, Inhee [Columbus, OH; Akbar, Sheikh A [Hilliard, OH

    2011-11-15

    The present invention generally relates to carbon dioxide (CO.sub.2) sensors. In one embodiment, the present invention relates to a carbon dioxide (CO.sub.2) sensor that incorporates lithium phosphate (Li.sub.3PO.sub.4) as an electrolyte and sensing electrode comprising a combination of lithium carbonate (Li.sub.2CO.sub.3) and barium carbonate (BaCO.sub.3). In another embodiment, the present invention relates to a carbon dioxide (CO.sub.2) sensor has a reduced sensitivity to humidity due to a sensing electrode with a layered structure of lithium carbonate and barium carbonate. In still another embodiment, the present invention relates to a method of producing carbon dioxide (CO.sub.2) sensors having lithium phosphate (Li.sub.3PO.sub.4) as an electrolyte and sensing electrode comprising a combination of lithium carbonate (Li.sub.2CO.sub.3) and barium carbonate (BaCO.sub.3).

  7. Carbon dioxide and climate

    International Nuclear Information System (INIS)

    1991-10-01

    Global climate change is a serious environmental concern, and the US has developed ''An Action Agenda'' to deal with it. At the heart of the US effort is the US Global Change Research Program (USGCRP), which has been developed by the Committee on Earth and Environmental Sciences (CEES) of the Federal Coordinating Council for Sciences, Engineering, and Technology (FCCSET). The USGCRP will provide the scientific basis for sound policy making on the climate-change issue. The DOE contribution to the USGCRP is the Carbon Dioxide Research Program, which now places particular emphasis on the rapid improvement of the capability to predict global and regional climate change. DOE's Carbon Dioxide Research Program has been addressing the carbon dioxide-climate change connection for more than twelve years and has provided a solid scientific foundation for the USGCRP. The expansion of the DOE effort reflects the increased attention that the Department has placed on the issue and is reflected in the National Energy Strategy (NES) that was released in 1991. This Program Summary describes projects funded by the Carbon Dioxide Research Program during FY 1991 and gives a brief overview of objectives, organization, and accomplishments. The Environmental Sciences Division of the Office of Health and Environmental Research, Office of Energy Research supports a Carbon Dioxide Research Program to determine the scientific linkage between the rise of greenhouse gases in the atmosphere, especially carbon dioxide, and climate and vegetation change. One facet is the Core CO 2 Program, a pioneering program that DOE established more than 10 years ago to understand and predict the ways that fossil-fuel burning could affect atmospheric CO 2 concentration, global climate, and the Earth's biosphere. Major research areas are: global carbon cycle; climate detection and models of climate change; vegetation research; resource analysis; and, information and integration

  8. Evaluation of a membrane based carbon dioxide absorber for spacecraft ECLS applications

    NARCIS (Netherlands)

    Feron, P.H.M.; Eckhard, F.; Witt, J.

    1996-01-01

    In an on-going harmonized ESA/NIVR project, performed by Stork Comprimo and TNO-MEP, the removal of the carbon dioxide with membranes is studied. The use of membrane gas absorption for carbon dioxide removal is currently hampered by the fact that the commonly used alkanolamines result in leakage

  9. Deposition of carbon dioxide

    International Nuclear Information System (INIS)

    2001-01-01

    In Norway, there is currently a debate about whether or not to build gas power stations. To meet the possibility of reduced emission quotas for carbon dioxide in the future, current interest focuses on the incorporation of large-scale separation and deposition of carbon dioxide when such plants are planned. A group of experts concludes that this technology will become self-financing by means of environmental taxes. From the environmental point of view, taxes upon production are to be preferred over taxes on consumption

  10. Does Carbon Dioxide Predict Temperature?

    OpenAIRE

    Mytty, Tuukka

    2013-01-01

    Does carbon dioxide predict temperature? No it does not, in the time period of 1880-2004 with the carbon dioxide and temperature data used in this thesis. According to the Inter Governmental Panel on Climate Change(IPCC) carbon dioxide is the most important factor in raising the global temperature. Therefore, it is reasonable to assume that carbon dioxide truly predicts temperature. Because this paper uses observational data it has to be kept in mind that no causality interpretation can be ma...

  11. Carbon Dioxide Sensor Technology.

    Science.gov (United States)

    1983-04-01

    second gas permeable membrane separates a compartment containing the non-aqueous " solvent dimethylsulfoxide , ( DMSO ), from the aqueous solution...compartment. In DMSO carbon dioxide can be irreversibly reduced electrochemically to * non-interfering products...current due to its reduction in the DMSO solution is proportional to the partial pressure of CO2 in the gas phase. Overall, the linear response and

  12. Balancing atmospheric carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Goreau, T.J. (Discovery Bay Marine Laboratory, Univ. of the West Indies (JM))

    1990-01-01

    Rising carbon dioxide and global temperatures are causing increasing worldwide concern, and pressure towards an international law of the atmosphere is rapidly escalating, yet widespread misconceptions about the greenhouse effect's inevitability, time scale, and causes have inhibited effective consensus and action. Observations from Antarctic ice cores, Amazonian rain forests, and Carribean coral reefs suggest that the biological effects of climate change may be more severe than climate models predict. Efforts to limit emissions from fossil-fuel combustion alone are incapable of stabilizing levels of carbon dioxide in the atmosphere. Stabilizing atmospheric carbon dioxide requires coupled measures to balance sources and sinks of the gas, and will only be viable with large-scale investments in increased sustainable productivity on degraded tropical soils, and in long-term research on renewable energy and biomass product development in the developing countries. A mechanism is outlined which directly links fossil-fuel combustion sources of carbon dioxide to removal via increasing biotic productivity and storage. A preliminary cost-benefit analysis suggests that such measures are very affordable, costing far less than inaction. (With 88 refs.).

  13. Balancing atmospheric carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Goreau, T J [Discovery Bay Marine Laboratory, Univ. of the West Indies (JM)

    1990-01-01

    Rising carbon dioxide and global temperatures are causing increasing worldwide concern, and pressure towards an international law of the atmosphere is rapidly escalating, yet widespread misconceptions about the greenhouse effect's inevitability, time scale, and causes have inhibited effective consensus and action. Observations from Antarctic ice cores, Amazonian rain forests, and Carribean coral reefs suggest that the biological effects of climate change may be more severe than climate models predict. Efforts to limit emissions from fossil-fuel combustion alone are incapable of stabilizing levels of carbon dioxide in the atmosphere. Stabilizing atmospheric carbon dioxide requires coupled measures to balance sources and sinks of the gas, and will only be viable with large-scale investments in increased sustainable productivity on degraded tropical soils, and in long-term research on renewable energy and biomass product development in the developing countries. A mechanism is outlined which directly links fossil-fuel combustion sources of carbon dioxide to removal via increasing biotic productivity and storage. A preliminary cost-benefit analysis suggests that such measures are very affordable, costing far less than inaction. (With 88 refs.).

  14. EVALUATION OF CARBON DIOXIDE CAPTURE FROM EXISTING COAL FIRED PLANTS BY HYBRID SORPTION USING SOLID SORBENTS

    Energy Technology Data Exchange (ETDEWEB)

    Benson, Steven; Browers, Bruce; Srinivasachar, Srivats; Laudal, Daniel

    2014-12-31

    Under contract DE-FE0007603, the University of North Dakota conducted the project Evaluation of Carbon Dioxide Capture from Existing Coal Fired Plants by Hybrid Sorption Using Solid Sorbents. As an important element of this effort, a Technical and Economic Feasibility Study was conducted by Barr Engineering Co. (Barr) in association with the University of North Dakota. The assessment developed a process flow diagram, major equipment list, heat balances for the SCPC power plant, capital cost estimate, operating cost estimate, levelized cost of electricity, cost of CO2 capture ($/ton) and three sensitivity cases for the CACHYS™ process.

  15. Carbon dioxide dangers demonstration model

    Science.gov (United States)

    Venezky, Dina; Wessells, Stephen

    2010-01-01

    Carbon dioxide is a dangerous volcanic gas. When carbon dioxide seeps from the ground, it normally mixes with the air and dissipates rapidly. However, because carbon dioxide gas is heavier than air, it can collect in snowbanks, depressions, and poorly ventilated enclosures posing a potential danger to people and other living things. In this experiment we show how carbon dioxide gas displaces oxygen as it collects in low-lying areas. When carbon dioxide, created by mixing vinegar and baking soda, is added to a bowl with candles of different heights, the flames are extinguished as if by magic.

  16. Methanation of Carbon Dioxide

    OpenAIRE

    Goodman, Daniel Jacob

    2013-01-01

    The emission of greenhouse gases into the atmosphere has been linked to global warming. Carbon dioxide's (CO2) one of the most abundant greenhouse gases. Natural gas, mainly methane, is the cleanest fossil fuel for electricity production helping meet the United States ever growing energy needs. The methanation of CO2 has the potential to address both of these problems if a catalyst can be developed that meets the activity, economic and environmental requirements to industrialize the process. ...

  17. CARBON DIOXIDE FIXATION.

    Energy Technology Data Exchange (ETDEWEB)

    FUJITA,E.

    2000-01-12

    Solar carbon dioxide fixation offers the possibility of a renewable source of chemicals and fuels in the future. Its realization rests on future advances in the efficiency of solar energy collection and development of suitable catalysts for CO{sub 2} conversion. Recent achievements in the efficiency of solar energy conversion and in catalysis suggest that this approach holds a great deal of promise for contributing to future needs for fuels and chemicals.

  18. EVALUATION OF CARBON DIOXIDE CAPTURE FROM EXISTING COAL FIRED PLANTS BY HYBRID SORPTION USING SOLID SORBENTS

    Energy Technology Data Exchange (ETDEWEB)

    Benson, Steven; Palo, Daniel; Srinivasachar, Srivats; Laudal, Daniel

    2014-12-01

    Under contract DE-FE0007603, the University of North Dakota conducted the project Evaluation of Carbon Dioxide Capture from Existing Coal Fired Plants by Hybrid Sorption Using Solid Sorbents. As an important element of this effort, an Environmental Health and Safety (EH&S) Assessment was conducted by Barr Engineering Co. (Barr) in association with the University of North Dakota. The assessment addressed air and particulate emissions as well as solid and liquid waste streams. The magnitude of the emissions and waste streams was estimated for evaluation purposes. EH&S characteristics of materials used in the system are also described. This document contains data based on the mass balances from both the 40 kJ/mol CO2 and 80 kJ/mol CO2 desorption energy cases evaluated in the Final Technical and Economic Feasibility study also conducted by Barr Engineering.

  19. Evaluation of process costs for small-scale carbon dioxide removal from natural gas. Topical report, September 1989-December 1989

    International Nuclear Information System (INIS)

    Changela, M.K.; Reading, G.J.; Echterhoff, L.W.

    1991-08-01

    The report establishes the cost of producing pipeline quality gas on a small scale from high carbon dioxide subquality natural gas. Two processing technologies are evaluated: conventional diethanolamine (DEA) absorption and membrane separation. Comparison of the established costs shows both capital and operating cost advantages for small-scale membrane applications. Membranes offer higher cost savings at low feed flow rates and high carbon dioxide feed contents. Membranes are produced in modules, thus they do not exhibit economies of scale. This works to their advantage for removing carbon dioxide on a small scale. Processing costs for amine systems are more sensitive to economies of scale, and thus decrease more rapidly than for membranes at higher feed flow rates. The report shows that membranes have a definite market niche within the natural gas processing arena. For economic reasons, membranes will likely become the technology of choice for small-scale systems that treat high carbon dioxide content natural gas streams. However, amines will continue to service large-scale systems and applications where deep carbon dioxide removal is required. A related report (GRI Report No. GRI-91/0093 entitled, 'Technical Evaluation of Hybrid Membrane/DEA Modeling') shows that hybrid systems, the integration of membranes and amines, also offer the potential to lower processing costs

  20. Evaluating the effectiveness of carbon tax for total emission control of carbon dioxide. Systems analysis of a dynamic environmental-economic model

    International Nuclear Information System (INIS)

    Tamura, Hiroyuki; Abe, Makoto; Tomiyama, Shinji; Hatono, Itsuo

    1999-01-01

    This paper deals with how to evaluate the effectiveness of carbon tax (environmental tax) for regulating the carbon dioxide emissions. For this purpose we mainly deal with a primal problem and its dual problem of dynamic linear programming model. The primal problem is formulated by using Leontief type input-output model and the basic idea of commodity stocks. It represents the balance of materials. The dual problem is obtained and interpreted as cash balance. It is clarified in this paper whether the carbon tax is effective to decrease the total amount of carbon dioxide emissions. (author)

  1. A gaseous measurement system for carbon-14 dioxide and carbon-14 methane: An analytical methodology to be applied in the evaluation of the carbon-14 dioxide and carbon-14 methane produced via microbial activity in volcanic tuff

    International Nuclear Information System (INIS)

    Dolan, M.M.

    1987-01-01

    The objectives of this study were to develop a gaseous measurement system for the carbon-14 dioxide and carbon-14 methane produced via microbial activity or geochemical action on leachate in tuff; to determine the trapping efficiency of the system for carbon-14 dioxide; to determine the trapping efficiency of the system for carbon-14 methane; to apply the experimentally determined factors regarding the system's trapping efficiency for carbon-14 dioxide and carbon-14 methane to a trapping algorithm to determine the activity of the carbon-14 dioxide and carbon-14 methane in a mixed sample; to determine the minimum detectable activity of the measurement process in picocuries per liter; and to determine the lower limit or detection of the measurement process in counts per minute

  2. Carbon dioxide sequestration by mineral carbonation

    NARCIS (Netherlands)

    Huijgen, W.J.J.

    2007-01-01

    The increasing atmospheric carbon dioxide (CO2) concentration, mainly caused by fossil fuel combustion, has lead to concerns about global warming. A possible technology that can contribute to the reduction of carbon dioxide emissions is CO2 sequestration by mineral carbonation. The basic concept

  3. Carbon dioxide and climate

    Energy Technology Data Exchange (ETDEWEB)

    1990-10-01

    Scientific and public interest in greenhouse gases, climate warming, and global change virtually exploded in 1988. The Department's focused research on atmospheric CO{sub 2} contributed sound and timely scientific information to the many questions produced by the groundswell of interest and concern. Research projects summarized in this document provided the data base that made timely responses possible, and the contributions from participating scientists are genuinely appreciated. In the past year, the core CO{sub 2} research has continued to improve the scientific knowledge needed to project future atmospheric CO{sub 2} concentrations, to estimate climate sensitivity, and to assess the responses of vegetation to rising concentrations of CO{sub 2} and to climate change. The Carbon Dioxide Research Program's goal is to develop sound scientific information for policy formulation and governmental action in response to changes of atmospheric CO{sub 2}. The Program Summary describes projects funded by the Carbon Dioxide Research Program during FY 1990 and gives a brief overview of objectives, organization, and accomplishments.

  4. Carbon dioxide quantified by the infrared in evaluation of respiratory activity of wheat seeds

    Directory of Open Access Journals (Sweden)

    João Alexandre Lopes Dranski

    Full Text Available ABSTRACT The objective of this study was to develop and validate the methodology of carbon dioxide concentration in the evaluation of vigor of Triticum aestivum L. seeds based on infrared spectroscopy. The proposed method quantifies CO2 content using a drag system and exhaustion to the gas released by the seeds. Samples of 50 seeds of six lots of cultivar CD 123 were incubated at temperatures of 15, 25 and 40 °C. The CO2 content released after 1, 3, 6, 9, 12 and 24 h of incubation were quantified. Additionally, the percentage of normal seedlings emerged in the field were evaluated. The simple correlation coefficients were evaluated among tests. After determining the reading conditions, the precision and accuracy of the proposed method were evaluated, using 15 lots of seeds. For the evaluation of the respiratory activity in Triticum aestivum seeds, a sample of 25 seeds, incubated at 25 °C for a minimum of 12 h is recommended since it allows to classify lots with different levels of vigor and predict the establishment of seedlings in the field, being the appropriate method for measuring CO2 as it externalizes precision between successive measurements and agreement with the reference method.

  5. Carbon Dioxide Capture from Flue Gas : Development and Evaluation of Existing and Novel Process Concepts

    NARCIS (Netherlands)

    Abu Zahra, M.R.M.

    2009-01-01

    One of the main global challenges in the years to come is to reduce the CO2 emissions in view of the apparent contribution to global warming. Carbon dioxide capture, transport, and storage (CCS) from fossil fuel fired power plants is drawing increased interest as an intermediate solution towards

  6. Evaluation of a transportable capnometer for monitoring end-tidal carbon dioxide

    DEFF Research Database (Denmark)

    Hildebrandt, T; Tobiasen, Malene Espelund; Olsen, K S

    2010-01-01

    We compared a small and transportable Capnometer (EMMA™) with a reference capnometer, the Siesta i TS Anaesthesia. During air-breathing through a facemask, both the EMMA (nine modules) and reference capnometer sampled expired gas simultaneously. A wide range of end-tidal carbon dioxide values were...... obtained during inhalation of carbon dioxide and voluntary hyperventilation. The median IQR [range] difference between all sets of carbon dioxide values (EMMA - reference) was -0.3 (-0.6 to 0.0 [-1.7 to 1.6] kPa; n = 297) using new batteries, which was statistically significant (p = 0.04) and located...... to two of the nine EMMAs tested. Using batteries with reduced voltage did not influence the measurements. The 95% CI of the medians of the differences were -0.4 to -0.2. We conclude that the EMMA can slightly under-read the end-tidal carbon dioxide but is generally comparable with a free-standing monitor...

  7. Evaluation of statistical protocols for quality control of ecosystem carbon dioxide fluxes

    Science.gov (United States)

    Jorge F. Perez-Quezada; Nicanor Z. Saliendra; William E. Emmerich; Emilio A. Laca

    2007-01-01

    The process of quality control of micrometeorological and carbon dioxide (CO2) flux data can be subjective and may lack repeatability, which would undermine the results of many studies. Multivariate statistical methods and time series analysis were used together and independently to detect and replace outliers in CO2 flux...

  8. Forecasting carbon dioxide emissions.

    Science.gov (United States)

    Zhao, Xiaobing; Du, Ding

    2015-09-01

    This study extends the literature on forecasting carbon dioxide (CO2) emissions by applying the reduced-form econometrics approach of Schmalensee et al. (1998) to a more recent sample period, the post-1997 period. Using the post-1997 period is motivated by the observation that the strengthening pace of global climate policy may have been accelerated since 1997. Based on our parameter estimates, we project 25% reduction in CO2 emissions by 2050 according to an economic and population growth scenario that is more consistent with recent global trends. Our forecasts are conservative due to that we do not have sufficient data to fully take into account recent developments in the global economy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. A new evaluation of the uncertainty associated with CDIAC estimates of fossil fuel carbon dioxide emission

    Directory of Open Access Journals (Sweden)

    Robert J. Andres

    2014-07-01

    Full Text Available Three uncertainty assessments associated with the global total of carbon dioxide emitted from fossil fuel use and cement production are presented. Each assessment has its own strengths and weaknesses and none give a full uncertainty assessment of the emission estimates. This approach grew out of the lack of independent measurements at the spatial and temporal scales of interest. Issues of dependent and independent data are considered as well as the temporal and spatial relationships of the data. The result is a multifaceted examination of the uncertainty associated with fossil fuel carbon dioxide emission estimates. The three assessments collectively give a range that spans from 1.0 to 13% (2 σ. Greatly simplifying the assessments give a global fossil fuel carbon dioxide uncertainty value of 8.4% (2 σ. In the largest context presented, the determination of fossil fuel emission uncertainty is important for a better understanding of the global carbon cycle and its implications for the physical, economic and political world.

  10. Carbon dioxide and future climate

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, J M

    1977-03-01

    The addition of carbon dioxide to the atmosphere due to burning fossil fuel is discussed. The release rate of carbon dioxide has been growing since at least 1950 at an average rate of 4.3% per year. If all known fossil fuel reserves in the world are consumed, a total of between 5 and 14 times the present amount of carbon dioxide in the atmosphere will be released. The oceans would then be unlikely to withdraw the proportion of perhaps 40% which they are believed to have withdrawn up to the present. The increase in the atmosphere would be in excess of 3 times or conceivably ten times the present amount. If the reserves are used up within a few hundred years, more than half the excess carbon dioxide would remain in the atmosphere after a thousand years. The ''greenhouse'' effect of carbon dioxide is explained. The simulation with numerical models of the effects of carbon dioxide on atmospheric radiation fluxes is discussed. An estimated increase in the average annual temperature of the earth of 2.4 to 2.9C is given for doubling the carbon dioxide content; also a 7% increase in global average precipitation. The effect of increasing carbon dioxide on global mean temperature is viewed in the perspective of the glacial-interglacial cycles. The warming effect of carbon dioxide may induce a ''super-interglacial'' on the present interglacial which is expected to decline toward a new ice age in the next several thousand years. Finally it is proposed that it may be necessary to phase out the use of fossil fuels before all the knowledge is acquired which would necessitate such an action.

  11. Evaluation of Refrigerating and Air Conditioning Devices in Energy Cascade Systems under the Restriction of Carbon Dioxide Emissions

    Science.gov (United States)

    Shimazaki, Yoichi; Akisawa, Atsushi; Kashiwagi, Takao

    It is necessary to introduce energy cascade systems into the industrial sector in Japan to reduce carbon dioxide emissions. The aim of this study is to evaluate the refrigerating and air conditioning devices in cases of introducing both energy cascade systems and thermal recycling systems in industries located around urban areas. The authors have developed an energy cascade model based on linear programming so as to minimize the total system costs with carbon taxes. Five cases are investigated. Limitation of carbon dioxide emissions results in the enhancement of heat cascading, where high temperature heat is supplied for process heating while low temperature one is shifted to refrigeration. It was found that increasing the amount of garbage combustor waste heat can reduce electric power for the turbo refrigerator by promoting waste heat driven ammonia absorption refrigerator.

  12. Reducing carbon dioxide to products

    Science.gov (United States)

    Cole, Emily Barton; Sivasankar, Narayanappa; Parajuli, Rishi; Keets, Kate A

    2014-09-30

    A method reducing carbon dioxide to one or more products may include steps (A) to (C). Step (A) may bubble said carbon dioxide into a solution of an electrolyte and a catalyst in a divided electrochemical cell. The divided electrochemical cell may include an anode in a first cell compartment and a cathode in a second cell compartment. The cathode may reduce said carbon dioxide into said products. Step (B) may adjust one or more of (a) a cathode material, (b) a surface morphology of said cathode, (c) said electrolyte, (d) a manner in which said carbon dioxide is bubbled, (e), a pH level of said solution, and (f) an electrical potential of said divided electrochemical cell, to vary at least one of (i) which of said products is produced and (ii) a faradaic yield of said products. Step (C) may separate said products from said solution.

  13. Method for carbon dioxide sequestration

    Science.gov (United States)

    Wang, Yifeng; Bryan, Charles R.; Dewers, Thomas; Heath, Jason E.

    2017-12-05

    A method for geo-sequestration of a carbon dioxide includes selection of a target water-laden geological formation with low-permeability interbeds, providing an injection well into the formation and injecting supercritical carbon dioxide (SC-CO.sub.2) and water or bine into the injection well under conditions of temperature, pressure and density selected to cause the fluid to enter the formation and splinter and/or form immobilized ganglia within the formation.

  14. Recuperative supercritical carbon dioxide cycle

    Science.gov (United States)

    Sonwane, Chandrashekhar; Sprouse, Kenneth M; Subbaraman, Ganesan; O'Connor, George M; Johnson, Gregory A

    2014-11-18

    A power plant includes a closed loop, supercritical carbon dioxide system (CLS-CO.sub.2 system). The CLS-CO.sub.2 system includes a turbine-generator and a high temperature recuperator (HTR) that is arranged to receive expanded carbon dioxide from the turbine-generator. The HTR includes a plurality of heat exchangers that define respective heat exchange areas. At least two of the heat exchangers have different heat exchange areas.

  15. Evaluation and Optimization of a Supercritical Carbon Dioxide Power Conversion Cycle for Nuclear Applications

    International Nuclear Information System (INIS)

    Harvego, Edwin A.; McKellar, Michael G.

    2011-01-01

    There have been a number of studies involving the use of gases operating in the supercritical mode for power production and process heat applications. Supercritical carbon dioxide (CO2) is particularly attractive because it is capable of achieving relatively high power conversion cycle efficiencies in the temperature range between 550 C and 750 C. Therefore, it has the potential for use with any type of high-temperature nuclear reactor concept, assuming reactor core outlet temperatures of at least 550 C. The particular power cycle investigated in this paper is a supercritical CO2 Recompression Brayton Cycle. The CO2 Recompression Brayton Cycle can be used as either a direct or indirect power conversion cycle, depending on the reactor type and reactor outlet temperature. The advantage of this cycle when compared to the helium Brayton Cycle is the lower required operating temperature; 550 C versus 850 C. However, the supercritical CO2 Recompression Brayton Cycle requires an operating pressure in the range of 20 MPa, which is considerably higher than the required helium Brayton cycle operating pressure of 8 MPa. This paper presents results of analyses performed using the UniSim process analyses software to evaluate the performance of the supercritical CO2 Brayton Recompression Cycle for different reactor outlet temperatures. The UniSim model assumed a 600 MWt reactor power source, which provides heat to the power cycle at a maximum temperature of between 550 C and 750 C. The UniSim model used realistic component parameters and operating conditions to model the complete power conversion system. CO2 properties were evaluated, and the operating range for the cycle was adjusted to take advantage of the rapidly changing conditions near the critical point. The UniSim model was then optimized to maximize the power cycle thermal efficiency at the different maximum power cycle operating temperatures. The results of the analyses showed that power cycle thermal efficiencies in

  16. An Evaluation of the Feasibility of Combining Carbon Dioxide Flooding Technologies with Microbial Enhanced Oil Recovery Technologies in Order To Sequester Carbon Dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Todd French; Lew Brown; Rafael Hernandez; Magan Green; Lynn Prewitt; Terry Coggins

    2009-08-19

    The need for more energy as our population grows results in an increase in the amount of CO2 introduced into the atmosphere. The effect of this introduction is currently debated intensely as to the severity of the effect of this. The bjective of this investigation was to determine if the production of more energy (i.e. petroleum) and the sequestration of CO2 could be coupled into one process. Carbon dioxide flooding is a well-established technique that introduces Compressed CO2 into a subsurface oil-bearing formation to aide in liquefying harder to extract petroleum and enhancing its mobility towards the production wells.

  17. Evaluation and optimization of a supercritical carbon dioxide power conversion cycle for nuclear applications

    International Nuclear Information System (INIS)

    Harvego, Edwin A.; McKellar, Michael G.

    2011-01-01

    There have been a number of studies involving the use of gases operating in the supercritical mode for power production and process heat applications. Supercritical carbon dioxide (CO 2 ) is particularly attractive because it is capable of achieving relatively high power conversion cycle efficiencies in the temperature range between 550degC and 750degC. Therefore, it has the potential for use with any type of high-temperature nuclear reactor concept, assuming reactor core outlet temperatures of at least 550degC. The particular power cycle investigated in this paper is a supercritical CO 2 recompression Brayton Cycle. The CO 2 recompression Brayton Cycle can be used as either a direct or indirect power conversion cycle, depending on the reactor type and reactor outlet temperature. The advantage of this cycle when compared to the helium Brayton Cycle is the lower required operating temperature; 550degC versus 750degC. However, the supercritical CO 2 recompression Brayton Cycle requires a high end operating pressure in the range of 20 MPa, which is considerably higher than the required helium Brayton cycle high end operating pressure of 7 MPa. This paper presents results of analyses performed using the UniSim process analyses software to evaluate the performance of the supercritical CO 2 recompression Brayton cycle for different reactor coolant outlet temperatures and mass flow rates. The UniSim model assumed a 600 MWt reactor power source, which provides heat to the power cycle at a maximum temperature of between 550degC and 850degC. Sensitivity calculations were also performed to determine the affect of reactor coolant mass flow rates for a reference reactor coolant outlet temperature of 750degC. The UniSim model used realistic component parameters and operating conditions to model the complete power conversion system. CO 2 properties were evaluated, and the operating range for the cycle was adjusted to take advantage of the rapidly changing conditions near the

  18. Carbon dioxide: emissions and effects

    Energy Technology Data Exchange (ETDEWEB)

    Smith, I M

    1982-01-01

    This review provides a comprehensive guide to work carried out since 1978 in the many disciplines involved in this complex issue. Possible scenarios for carbon dioxide emissions, sources and sinks in the carbon cycle and for climatic changes are examined. The current concensus (by no means unanimous) of specialists on this issue appears to be that a continuation of reduced trends in energy consumption since 1973 is likely to double the atmospheric carbon dioxide concentration to 600 ppmv during the latter part of the next century. However, a higher demand scenario, requiring an upper limit of coal production, would bring forward the doubling to about the middle of the next century. Current climatic models predict that such a concentration of carbon dioxide would cause an average global warming of from 1.0 to 4.5/sup 0/C which might be delayed by the thermal inertia of the oceans. A warming due to estimated increases in carbon dioxide should, if the model results are correct, become apparent at the end of this century. Regional climatic changes are likely to vary considerably and prove disadvantageous to some regions and beneficial to others. Different strategies for dealing with the carbon dioxide issue are considered: no response, alleviation, countermeasures and prevention. It is concluded that uncertainties do not justify either the use of carbon dioxide disposal and other technical fixes at present or a policy of no further growth in fossil fuel consumption. On the other hand, major efforts to conserve energy would give more time to adapt to changes. The alleviation of climatic impacts and other desirable dual-benefit measures are advocated in addition to continuing international, interdisciplinary research on all aspects.

  19. Carbon Dioxide Absorption Heat Pump

    Science.gov (United States)

    Jones, Jack A. (Inventor)

    2002-01-01

    A carbon dioxide absorption heat pump cycle is disclosed using a high pressure stage and a super-critical cooling stage to provide a non-toxic system. Using carbon dioxide gas as the working fluid in the system, the present invention desorbs the CO2 from an absorbent and cools the gas in the super-critical state to deliver heat thereby. The cooled CO2 gas is then expanded thereby providing cooling and is returned to an absorber for further cycling. Strategic use of heat exchangers can increase the efficiency and performance of the system.

  20. Carbon Dioxide Embolism during Laparoscopic Surgery

    Science.gov (United States)

    Park, Eun Young; Kwon, Ja-Young

    2012-01-01

    Clinically significant carbon dioxide embolism is a rare but potentially fatal complication of anesthesia administered during laparoscopic surgery. Its most common cause is inadvertent injection of carbon dioxide into a large vein, artery or solid organ. This error usually occurs during or shortly after insufflation of carbon dioxide into the body cavity, but may result from direct intravascular insufflation of carbon dioxide during surgery. Clinical presentation of carbon dioxide embolism ranges from asymptomatic to neurologic injury, cardiovascular collapse or even death, which is dependent on the rate and volume of carbon dioxide entrapment and the patient's condition. We reviewed extensive literature regarding carbon dioxide embolism in detail and set out to describe the complication from background to treatment. We hope that the present work will improve our understanding of carbon dioxide embolism during laparoscopic surgery. PMID:22476987

  1. Process for sequestering carbon dioxide and sulfur dioxide

    Science.gov (United States)

    Maroto-Valer, M Mercedes [State College, PA; Zhang, Yinzhi [State College, PA; Kuchta, Matthew E [State College, PA; Andresen, John M [State College, PA; Fauth, Dan J [Pittsburgh, PA

    2009-10-20

    A process for sequestering carbon dioxide, which includes reacting a silicate based material with an acid to form a suspension, and combining the suspension with carbon dioxide to create active carbonation of the silicate-based material, and thereafter producing a metal salt, silica and regenerating the acid in the liquid phase of the suspension.

  2. High capacity carbon dioxide sorbent

    Science.gov (United States)

    Dietz, Steven Dean; Alptekin, Gokhan; Jayaraman, Ambalavanan

    2015-09-01

    The present invention provides a sorbent for the removal of carbon dioxide from gas streams, comprising: a CO.sub.2 capacity of at least 9 weight percent when measured at 22.degree. C. and 1 atmosphere; an H.sub.2O capacity of at most 15 weight percent when measured at 25.degree. C. and 1 atmosphere; and an isosteric heat of adsorption of from 5 to 8.5 kilocalories per mole of CO.sub.2. The invention also provides a carbon sorbent in a powder, a granular or a pellet form for the removal of carbon dioxide from gas streams, comprising: a carbon content of at least 90 weight percent; a nitrogen content of at least 1 weight percent; an oxygen content of at most 3 weight percent; a BET surface area from 50 to 2600 m.sup.2/g; and a DFT micropore volume from 0.04 to 0.8 cc/g.

  3. Modelling Sublimation of Carbon Dioxide

    Science.gov (United States)

    Winkel, Brian

    2012-01-01

    In this article, the author reports results in their efforts to model sublimation of carbon dioxide and the associated kinetics order and parameter estimation issues in their model. They have offered the reader two sets of data and several approaches to determine the rate of sublimation of a piece of solid dry ice. They presented several models…

  4. 21 CFR 582.1240 - Carbon dioxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Carbon dioxide. 582.1240 Section 582.1240 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1240 Carbon dioxide. (a) Product. Carbon dioxide. (b) Conditions of use. This substance is generally...

  5. Nongovernmental valorization of carbon dioxide

    International Nuclear Information System (INIS)

    Petersen, Gene; Viviani, Donn; Magrini-Bair, Kim; Kelley, Stephen; Moens, Luc; Shepherd, Phil; DuBois, Dan

    2005-01-01

    Carbon dioxide (CO 2 ) is considered the largest contributor to the greenhouse gas effect. Most attempts to manage the flow of CO 2 or carbon into our environment involve reducing net emissions or sequestering the gas into long-lived sinks. Using CO 2 as a chemical feedstock has a long history, but using it on scales that might impact the net emissions of CO 2 into the atmosphere has not generally been considered seriously. There is also a growing interest in employing our natural biomes of carbon such as trees, vegetation, and soils as storage media. Some amelioration of the net carbon emissions into the atmosphere could be achieved by concomitant large withdrawals of carbon. This report surveys the potential and limitations in employing carbon as a resource for organic chemicals, fuels, inorganic materials, and in using the biome to manage carbon. The outlook for each of these opportunities is also described

  6. Carbon dioxide capture and storage

    International Nuclear Information System (INIS)

    Durand, B.

    2011-01-01

    The author first highlights the reasons why storing carbon dioxide in geological formations could be a solution in the struggle against global warming and climate change. Thus, he comments various evolutions and prospective data about carbon emissions or fossil energy consumption as well as various studies performed by international bodies and agencies which show the interest of carbon dioxide storage. He comments the evolution of CO 2 contributions of different industrial sectors and activities, notably in France. He presents the different storage modes and methods which concern different geological formations (saline aquifers, abandoned oil or gas fields, not exploitable coal seams) and different processes (sorption, carbonation). He discusses the risks associated with these storages, the storable quantities, evokes some existing installations in different countries. He comments different ways to capture carbon dioxide (in post-combustion, through oxy-combustion, by pre-combustion) and briefly evokes some existing installations. He evokes the issue of transport, and discusses efficiency and cost aspects, and finally has few words on legal aspects and social acceptability

  7. CARBON DIOXIDE AS A FEEDSTOCK.

    Energy Technology Data Exchange (ETDEWEB)

    CREUTZ,C.; FUJITA,E.

    2000-12-09

    This report is an overview on the subject of carbon dioxide as a starting material for organic syntheses of potential commercial interest and the utilization of carbon dioxide as a substrate for fuel production. It draws extensively on literature sources, particularly on the report of a 1999 Workshop on the subject of catalysis in carbon dioxide utilization, but with emphasis on systems of most interest to us. Atmospheric carbon dioxide is an abundant (750 billion tons in atmosphere), but dilute source of carbon (only 0.036 % by volume), so technologies for utilization at the production source are crucial for both sequestration and utilization. Sequestration--such as pumping CO{sub 2} into sea or the earth--is beyond the scope of this report, except where it overlaps utilization, for example in converting CO{sub 2} to polymers. But sequestration dominates current thinking on short term solutions to global warming, as should be clear from reports from this and other workshops. The 3500 million tons estimated to be added to the atmosphere annually at present can be compared to the 110 million tons used to produce chemicals, chiefly urea (75 million tons), salicylic acid, cyclic carbonates and polycarbonates. Increased utilization of CO{sub 2} as a starting material is, however, highly desirable, because it is an inexpensive, non-toxic starting material. There are ongoing efforts to replace phosgene as a starting material. Creation of new materials and markets for them will increase this utilization, producing an increasingly positive, albeit small impact on global CO{sub 2} levels. The other uses of interest are utilization as a solvent and for fuel production and these will be discussed in turn.

  8. Perspectives in the use of carbon dioxide

    Directory of Open Access Journals (Sweden)

    Aresta Michele

    1999-01-01

    Full Text Available The mitigation of carbon dioxide is one of the scientific and technological challenges of the 2000s. Among the technologies that are under assessment, the recovery of carbon dioxide from power plants or industrial flue gases plays a strategic role. Recovered carbon dioxide can be either disposed in natural fields or used. The availability of large amounts of carbon dioxide may open new routes to its utilisation in biological, chemical and innovative technological processes. In this paper, the potential of carbon dioxide utilisation in the short-, medium-term is reviewed.

  9. Evaluation and efficacy of carbon dioxide therapy (carboxytherapy) versus mesolipolysis in the treatment of cellulite.

    Science.gov (United States)

    Eldsouky, Fatma; Ebrahim, Howyda Mohamed

    2018-01-17

    Cellulite is an irregular alteration of the skin surface giving it cottage cheese appearance. Carboxytherapy is transcutaneous infusion of carbon dioxide into the affected site. Mesolipolysis aims to remove cellulite and improve skin texture. To verify the efficacy and safety of carboxytherapy versus mesolipolysis using phosphatidylcholine (PPC) in treatment of cellulite in thighs area. Forty-eight female patients with different grades of cellulite at thighs area were enrolled in this study. They were classified into two groups: group A received subcutaneous infusion of carboxytherapy, and group B was treated with mesolipolysis using PPC. Each group received six sessions at weekly intervals. sessions. The outcome measures and clinical assessment were based on cellulite grading scale and thigh circumference measurements. Standardized digital photography was taken before and after treatment. Patients were followed up for 6 months. After treatment, there was significant reduction in thigh circumference measurement p Carboxytherapy and mesolipolysis are safe and effective in cellulite treatment. Carboxytherapy is a promising alternative therapeutic modality for cellulite treatment.

  10. B33C-0612: Evaluation of Simulated Biospheric Carbon Dioxide Fluxes and Atmospheric Concentrations Using Global in Situ Observations

    Science.gov (United States)

    Philip, Sajeev; Johnson, Matthew S.; Potter, Christopher S.; Genovese, Vanessa

    2016-01-01

    Atmospheric mixing ratios of carbon dioxide (CO2) are largely controlled by anthropogenic emission sources and biospheric sources/sinks. Global biospheric fluxes of CO2 are controlled by complex processes facilitating the exchange of carbon between terrestrial ecosystems and the atmosphere. These processes which play a key role in these terrestrial ecosystem-atmosphere carbon exchanges are currently not fully understood, resulting in large uncertainties in the quantification of biospheric CO2 fluxes. Current models with these inherent deficiencies have difficulties simulating the global carbon cycle with high accuracy. We are developing a new modeling platform, GEOS-Chem-CASA by integrating the year-specific NASA-CASA (National Aeronautics and Space Administration - Carnegie Ames Stanford Approach) biosphere model with the GEOS-Chem (Goddard Earth Observation System-Chemistry) chemical transport model to improve the simulation of atmosphere-terrestrial ecosystem carbon exchange. We use NASA-CASA to explicitly represent the exchange of CO2 between terrestrial ecosystem and atmosphere by replacing the baseline GEOS-Chem land net CO2 flux and forest biomass burning CO2 emissions. We will present the estimation and evaluation of these "bottom-up" land CO2 fluxes, simulated atmospheric mixing ratios, and forest disturbance changes over the last decade. In addition, we will present our initial comparison of atmospheric column-mean dry air mole fraction of CO2 predicted by the model and those retrieved from NASA's OCO-2 (Orbiting Carbon Observatory-2) satellite instrument and model-predicted surface CO2 mixing ratios with global in situ observations. This evaluation is the first step necessary for our future work planned to constrain the estimates of biospheric carbon fluxes through "top-down" inverse modeling, which will improve our understanding of the processes controlling atmosphere-terrestrial ecosystem greenhouse gas exchanges, especially over regions which lack in

  11. Preliminary carbon dioxide capture technical and economic feasibility study evaluation of carbon dioxide capture from existing fired plants by hybrid sorption using solid sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Benson, Steven; Envergex, Srivats; Browers, Bruce; Thumbi, Charles

    2013-01-01

    Barr Engineering Co. was retained by the Institute for Energy Studies (IES) at University of North Dakota (UND) to conduct a technical and economic feasibility analysis of an innovative hybrid sorbent technology (CACHYS™) for carbon dioxide (CO2) capture and separation from coal combustion–derived flue gas. The project team for this effort consists of the University of North Dakota, Envergex LLC, Barr Engineering Co., and Solex Thermal Science, along with industrial support from Allete, BNI Coal, SaskPower, and the North Dakota Lignite Energy Council. An initial economic and feasibility study of the CACHYS™ concept, including definition of the process, development of process flow diagrams (PFDs), material and energy balances, equipment selection, sizing and costing, and estimation of overall capital and operating costs, is performed by Barr with information provided by UND and Envergex. The technology—Capture from Existing Coal-Fired Plants by Hybrid Sorption Using Solid Sorbents Capture (CACHYS™)—is a novel solid sorbent technology based on the following ideas: reduction of energy for sorbent regeneration, utilization of novel process chemistry, contactor conditions that minimize sorbent-CO2 heat of reaction and promote fast CO2 capture, and a low-cost method of heat management. The technology’s other key component is the use of a low-cost sorbent.

  12. Carbon isotope ratios of atmospheric carbon dioxide

    International Nuclear Information System (INIS)

    Sakai, Hitoshi; Kishima, Noriaki; Tsutaki, Yasuhiro.

    1982-01-01

    The delta 13 C values relative to PDB were measured for carbon dioxide in air samples collected at various parts of Japan and at Mauna Loa Observatory, Hawaii in the periods of 1977 and 1978. The delta 13 C values of the ''clean air'' are -7.6 % at Hawaii and -8.1 per mille Oki and Hachijo-jima islands. These values are definitely lighter than the carbon isotope ratios (-6.9 per mille) obtained by Keeling for clean airs collected at Southern California in 1955 to 1956. The increase in 12 C in atmospheric carbon dioxide is attributed to the input of the anthropogenic light carbon dioxides (combustion of fossil fuels etc.) Taking -7.6 per mille to be the isotope ratio of CO 2 in the present clean air, a simple three box model predicts that the biosphere has decreased rather than increased since 1955, implying that it is acting as the doner of carbon rather than the sink. (author)

  13. Oxygen and carbon dioxide sensing

    Science.gov (United States)

    Ren, Fan (Inventor); Pearton, Stephen John (Inventor)

    2012-01-01

    A high electron mobility transistor (HEMT) capable of performing as a CO.sub.2 or O.sub.2 sensor is disclosed, hi one implementation, a polymer solar cell can be connected to the HEMT for use in an infrared detection system. In a second implementation, a selective recognition layer can be provided on a gate region of the HEMT. For carbon dioxide sensing, the selective recognition layer can be, in one example, PEI/starch. For oxygen sensing, the selective recognition layer can be, in one example, indium zinc oxide (IZO). In one application, the HEMTs can be used for the detection of carbon dioxide and oxygen in exhaled breath or blood.

  14. Carbon dioxide retention in divers

    Energy Technology Data Exchange (ETDEWEB)

    Florio, J.T.; Mackenzie, D.A.R.; McKenzie, R.S. [ARE Physiological Laboratory, Gosport (United Kingdom)

    1998-04-01

    This report summarises the work carried out at the ARE Physiological Laboratory (ARE(PL)) between July 1978 and December 1983. The work was intended to examine the proposition that some divers have a low ventilatory response to carbon dioxide; that this results in a low ventilatory response to exercise with consequent hypercapnia; and that these characteristics put the diver at a greater-than-normal risk by increasing the individual`s susceptibility to oxygen toxicity and to other hazards associated with diving (e.g. nitrogen narcosis, decompression sickness and hypothermia). The specific aims of the project can be summarised as follows: (a) to demonstrate the existence of divers who exhibit the tendency to `retain carbon dioxide` when working in hyperbaric conditions; (b) to define the circumstances under which such individuals are at risk; (c) to assess the magnitude of the risk; and (d) to recommend ways to eliminate or to reduce the risk. (author)

  15. Carbon dioxide conversion over carbon-based nanocatalysts.

    Science.gov (United States)

    Khavarian, Mehrnoush; Chai, Siang-Piao; Mohamed, Abdul Rahman

    2013-07-01

    The utilization of carbon dioxide for the production of valuable chemicals via catalysts is one of the efficient ways to mitigate the greenhouse gases in the atmosphere. It is known that the carbon dioxide conversion and product yields are still low even if the reaction is operated at high pressure and temperature. The carbon dioxide utilization and conversion provides many challenges in exploring new concepts and opportunities for development of unique catalysts for the purpose of activating the carbon dioxide molecules. In this paper, the role of carbon-based nanocatalysts in the hydrogenation of carbon dioxide and direct synthesis of dimethyl carbonate from carbon dioxide and methanol are reviewed. The current catalytic results obtained with different carbon-based nanocatalysts systems are presented and how these materials contribute to the carbon dioxide conversion is explained. In addition, different strategies and preparation methods of nanometallic catalysts on various carbon supports are described to optimize the dispersion of metal nanoparticles and catalytic activity.

  16. 21 CFR 184.1240 - Carbon dioxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Carbon dioxide. 184.1240 Section 184.1240 Food and... Substances Affirmed as GRAS § 184.1240 Carbon dioxide. (a) Carbon dioxide (empirical formula CO2, CAS Reg. No.... The solid form, dry ice, sublimes under atmospheric pressure at a temperature of −78.5 °C. Carbon...

  17. Carbon Dioxide Removal via Passive Thermal Approaches

    Science.gov (United States)

    Lawson, Michael; Hanford, Anthony; Conger, Bruce; Anderson, Molly

    2011-01-01

    A paper describes a regenerable approach to separate carbon dioxide from other cabin gases by means of cooling until the carbon dioxide forms carbon dioxide ice on the walls of the physical device. Currently, NASA space vehicles remove carbon dioxide by reaction with lithium hydroxide (LiOH) or by adsorption to an amine, a zeolite, or other sorbent. Use of lithium hydroxide, though reliable and well-understood, requires significant mass for all but the shortest missions in the form of lithium hydroxide pellets, because the reaction of carbon dioxide with lithium hydroxide is essentially irreversible. This approach is regenerable, uses less power than other historical approaches, and it is almost entirely passive, so it is more economical to operate and potentially maintenance- free for long-duration missions. In carbon dioxide removal mode, this approach passes a bone-dry stream of crew cabin atmospheric gas through a metal channel in thermal contact with a radiator. The radiator is pointed to reject thermal loads only to space. Within the channel, the working stream is cooled to the sublimation temperature of carbon dioxide at the prevailing cabin pressure, leading to formation of carbon dioxide ice on the channel walls. After a prescribed time or accumulation of carbon dioxide ice, for regeneration of the device, the channel is closed off from the crew cabin and the carbon dioxide ice is sublimed and either vented to the environment or accumulated for recovery of oxygen in a fully regenerative life support system.

  18. Mass depopulation of laying hens in whole barns with liquid carbon dioxide: evaluation of welfare impact.

    Science.gov (United States)

    Turner, P V; Kloeze, H; Dam, A; Ward, D; Leung, N; Brown, E E L; Whiteman, A; Chiappetta, M E; Hunter, D B

    2012-07-01

    Appropriate emergency disaster preparedness is a key priority for agricultural agencies to allow effective response to serious avian disease outbreaks. There is a need to develop rapid, humane, and safe depopulation techniques for poultry that are widely applicable across a range of farm settings. Whole barn depopulation with carbon dioxide (CO(2)) has been investigated as a humane and efficient means of killing large numbers of birds in the event of a reportable disease outbreak. It has also been considered as a method for depopulating barns containing end-of-lay hens, particularly when there is limited local slaughter and rendering capacity. Determining the best method of humanely killing large flocks of birds remains problematic and is being investigated by a coordinated international effort. While whole barn depopulation using CO(2) inhalation has been explored, physiologic responses of chickens have not been characterized in field settings and assessment of animal welfare is hampered without this information. In this study, 12 cull laying hens were surgically instrumented with telemetry transmitters to record electroencephalographs, electrocardiographs, body temperature, and activity during 2 large-scale field CO(2) euthanasia trials of end-of-lay hens. The day following surgery, instrumented hens were placed in barns with other birds, barns were sealed, and animals were killed by CO(2) inhalation delivered via a specially designed liquid CO(2) manifold. Instrumented birds were monitored by infrared thermography, and ambient temperature, CO(2), and O(2) concentrations were recorded. Results from these studies indicate that instrumented hens lost consciousness within 2 min of CO(2) levels reaching 18 to 20%. Mild to moderate head shaking, gasping, and 1 to 2 clonic muscle contractions were noted in hens before unconsciousness; however, brain death followed rapidly (benefits suggest clear advantages over catching and transporting cull hens for slaughter. The

  19. Absorption of carbon dioxide in waste tanks

    International Nuclear Information System (INIS)

    Hobbs, D.T.

    1987-01-01

    Air flow rates and carbon dioxide concentrations of air entering and exiting eight H-Area waste tanks were monitored for a period of one year. The average instanteous concentration of carbon dioxide in air is within the range reported offsite, and therefore is not affect by operation of the coal-fired power plant adjacent to the tank farm. Waste solutions in each of the tanks were observed to be continuously absorbing carbon dioxide. The rate of absorption of carbon dioxide decreased linearly with the pH of the solution. Personnel exposure associated with the routine sampling and analysis of radioactive wastes stored at SRP to determine the levels of corrosion inhibitors in solution could be reduced by monitoring the absorption of carbon dioxide and using the relationship between pH and carbon dioxide absorption to determine the free hydroxide concentration in solution

  20. Understanding the carbon dioxide gaps.

    Science.gov (United States)

    Scheeren, Thomas W L; Wicke, Jannis N; Teboul, Jean-Louis

    2018-06-01

    The current review attempts to demonstrate the value of several forms of carbon dioxide (CO2) gaps in resuscitation of the critically ill patient as monitor for the adequacy of the circulation, as target for fluid resuscitation and also as predictor for outcome. Fluid resuscitation is one of the key treatments in many intensive care patients. It remains a challenge in daily practice as both a shortage and an overload in intravascular volume are potentially harmful. Many different approaches have been developed for use as target of fluid resuscitation. CO2 gaps can be used as surrogate for the adequacy of cardiac output (CO) and as marker for tissue perfusion and are therefore a potential target for resuscitation. CO2 gaps are easily measured via point-of-care analysers. We shed light on its potential use as nowadays it is not widely used in clinical practice despite its potential. Many studies were conducted on partial CO2 pressure differences or CO2 content (cCO2) differences either alone, or in combination with other markers for outcome or resuscitation adequacy. Furthermore, some studies deal with CO2 gap to O2 gap ratios as target for goal-directed fluid therapy or as marker for outcome. CO2 gap is a sensitive marker of tissue hypoperfusion, with added value over traditional markers of tissue hypoxia in situations in which an oxygen diffusion barrier exists such as in tissue oedema and impaired microcirculation. Venous-to-arterial cCO2 or partial pressure gaps can be used to evaluate whether attempts to increase CO should be made. Considering the potential of the several forms of CO2 measurements and its ease of use via point-of-care analysers, it is recommendable to implement CO2 gaps in standard clinical practice.

  1. Carbon dioxide for enhanced oil recovery in Canada

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, S.; Manbybura, F.; Sparks, N.

    1985-01-01

    This paper examines the potential for carbon dioxide as a major miscible solvent in Canada and describes Shell Canada's carbon dioxide exploration efforts over the last few years. Enhanced oil recovery, specifically miscible flooding, has been recognized as a technically and economically feasible method for adding reserves and productive capacity to Canada's light and medium oil. The fiscal regime has been altered by both the federal and provincial governments to encourage miscible flooding development. As a result many projects have been initiated with others being evaluated and designed. This paper analyzes the history and the direction of miscible flooding in the United States, where carbon dioxide is becoming the predominant miscible solvent. The potential for future use of carbon dioxide in Canada is specifically addressed: potential oil recovery solvent supply, and economics. Shell's carbon dioxide exploration play currently underway is also discussed.

  2. Forest response to carbon dioxide

    International Nuclear Information System (INIS)

    Pitelka, L.

    1992-01-01

    It has been suggested that planting trees could help slow the buildup of carbon dioxide in the atmosphere. Since elevated levels of CO 2 are known to enhance photosynthesis and growth in many plants, it is possible that trees could become progressively more effective in storing carbon as atmospheric CO 2 increases. However, early results from experiments with ponderosa and loblolly pines indicate that the relationship between tree growth and rising CO 2 concentrations may be more complex than scientists once thought. In these experiments, the response to elevated CO 2 has been highly dependent both on species and on mineral nutrient levels in the soil. Further work is necessary to clarify the mechanisms involved. This research will ultimately contribute to an integrated model for predicting forest ecosystem response to elevated CO 2

  3. Carbon Dioxide for pH Control

    Energy Technology Data Exchange (ETDEWEB)

    Wagonner, R.C.

    2001-08-16

    Cardox, the major supplier of carbon dioxide, has developed a diffuser to introduce carbon dioxide into a water volume as small bubbles to minimize reagent loss to the atmosphere. This unit is integral to several configurations suggested for treatment to control alkalinity in water streams.

  4. Trading coalbed methane for carbon dioxide

    International Nuclear Information System (INIS)

    Greenberger, L.S.

    1991-01-01

    This article discusses a proposal for reducing methane emissions in coal mining activities and at the same time reducing the burden on utilities to cut carbon dioxide emissions. Emission credits would be issued to mines that recover the methane for use. These credits could then be bought by utilities and exchanged for the right to emit carbon dioxide

  5. Pressure pumping of carbon dioxide from soil

    Science.gov (United States)

    E. S. Takle; J. R. Brandle; R. A. Schmidt; R. Garcia; I. V. Litvina; G. Doyle; X. Zhou; Q. Hou; C. W. Rice; W. J. Massman

    2000-01-01

    Recent interest in atmospheric increases in carbon dioxide have heightened the need for improved accuracy in measurements of fluxes of carbon dioxide from soils. Diffusional movement has long been considered the dominant process by which trace gases move from the subsurface source to the surface, although there has been some indication that atmospheric pressure...

  6. Carbon dioxide production in animal houses

    DEFF Research Database (Denmark)

    Pedersen, Søren; Blanes-Vidal, Victoria; Joergensen, H.

    2008-01-01

    cellars are emptied regularly in a four weeks interval. Due to a high and variable carbon dioxide production in deep straw litter houses and houses with indoor storage of manure longer than four weeks, we do not recommend to calculate the ventilation flow based on the carbon dioxide concentration......This article deals with carbon dioxide production from farm animals; more specifically, it addresses the possibilities of using the measured carbon dioxide concentration in animal houses as basis for estimation of ventilation flow (as the ventilation flow is a key parameter of aerial emissions from...... animal houses). The investigations include measurements in respiration chambers and in animal houses, mainly for growing pigs and broilers. Over the last decade a fixed carbon dioxide production of 185 litres per hour per heat production unit, hpu (i.e. 1000 W of the total animal heat production at 20o...

  7. Electrochemical processing of carbon dioxide.

    Science.gov (United States)

    Oloman, Colin; Li, Hui

    2008-01-01

    With respect to the negative role of carbon dioxide on our climate, it is clear that the time is ripe for the development of processes that convert CO(2) into useful products. The electroreduction of CO(2) is a prime candidate here, as the reaction at near-ambient conditions can yield organics such as formic acid, methanol, and methane. Recent laboratory work on the 100 A scale has shown that reduction of CO(2) to formate (HCO(2)(-)) may be carried out in a trickle-bed continuous electrochemical reactor under industrially viable conditions. Presuming the problems of cathode stability and formate crossover can be overcome, this type of reactor is proposed as the basis for a commercial operation. The viability of corresponding processes for electrosynthesis of formate salts and/or formic acid from CO(2) is examined here through conceptual flowsheets for two process options, each converting CO(2) at the rate of 100 tonnes per day.

  8. Reaction of yttrium polonides with carbon dioxide

    International Nuclear Information System (INIS)

    Abakumov, A.S.; Khokhlov, A.D.; Reznikova, N.F.

    1986-01-01

    It has been proved that heating of yttrium and tantalum in carbon dioxide to 500 and 800 0 C alters the gas phase composition, causing formation of carbon monoxide and reduction of oxygen content. A study of the thermal stability of yttrium polonides in carbon dioxide showed that yttrium sesqui- and monopolonides decompose at 400-430 0 C. The temperature dependence of the vapor pressure of polonium obtained upon decomposition of the referred polonides has been determined in a carbon dioxide environment radiotensometrically. The enthalpy of the process calculated from this dependence is close to the enthalpy of vaporization of elemental polonium in vacuo. The mechanism of the reactions has been suggested

  9. Application of a systematic methodology for sustainable carbon dioxide utilization process design

    DEFF Research Database (Denmark)

    Plaza, Cristina Calvera; Frauzem, Rebecca; Gani, Rafiqul

    than carbon capture and storage. To achieve this a methodology is developed to design sustainable carbon dioxide utilization processes. First, the information on the possible utilization alternatives is collected, including the economic potential of the process and the carbon dioxide emissions...... emission are desired in order to reduce the carbon dioxide emissions. Using this estimated preliminary evaluation, the top processes, with the most negative carbon dioxide emission are investigated by rigorous detailed simulation to evaluate the net carbon dioxide emissions. Once the base case design...

  10. Carbon dioxide cleaning pilot project

    International Nuclear Information System (INIS)

    Knight, L.; Blackman, T.E.

    1994-01-01

    In 1989, radioactive-contaminated metal at the Rocky Flats Plant (RFP) was cleaned using a solvent paint stripper (Methylene chloride). One-third of the radioactive material was able to be recycled; two-thirds went to the scrap pile as low-level mixed waste. In addition, waste solvent solutions also required disposal. Not only was this an inefficient process, it was later prohibited by the Resource Conservation and Recovery Act (RCRA), 40 CFR 268. A better way of doing business was needed. In the search for a solution to this situation, it was decided to study the advantages of using a new technology - pelletized carbon dioxide cleaning. A proof of principle demonstration occurred in December 1990 to test whether such a system could clean radioactive-contaminated metal. The proof of principle demonstration was expanded in June 1992 with a pilot project. The purpose of the pilot project was three fold: (1) to clean metal so that it can satisfy free release criteria for residual radioactive contamination at the Rocky Flats Plant (RFP); (2) to compare two different carbon dioxide cleaning systems; and (3) to determine the cost-effectiveness of decontamination process in a production situation and compare the cost of shipping the metal off site for waste disposal. The pilot project was completed in August 1993. The results of the pilot project were: (1) 90% of those items which were decontaminated, successfully met the free release criteria , (2) the Alpheus Model 250 was selected to be used on plantsite and (3) the break even cost of decontaminating the metal vs shipping the contaminated material offsite for disposal was a cleaning rate of 90 pounds per hour, which was easily achieved

  11. More bad news about carbon dioxide emissions

    International Nuclear Information System (INIS)

    Stonehouse, D.

    2000-01-01

    The affect that increased carbon dioxide concentrations has on plants and animals was discussed. Most research focuses on the impacts that carbon dioxide concentrations has on climatic change. Recent studies, however, have shown that elevated levels of carbon dioxide in the atmosphere caused by burning fossils fuels changes the chemical structure of plants and could lead to significant disruptions in ecological food chains. High carbon dioxide levels cause plants to speed up photosynthesis, take in the gas, and use the carbon to produce more fibre and starch while giving off oxygen as a byproduct. As plants produce more carbon, their levels of nitrogen diminish making them less nutritious for the insects and animals that feed on them. This has serious implications for farmers, as pests would have to eat more of their crops to survive. In addition, farmers would have to supplement livestock with nutrients

  12. Fixation of carbon dioxide into dimethyl carbonate over ...

    Science.gov (United States)

    A titanium-based zeolitic thiophene-benzimidazolate framework has been designed for the direct synthesis of dimethyl carbonate (DMC) from methanol and carbon dioxide. The developed catalyst activates carbon dioxide and delivers over 16% yield of DMC without the use of any dehydrating agent or requirement for azeotropic distillation. Prepared for submission to Nature Scientific reports.

  13. Evaluating the impact of the carbon dioxide capturing process on the indices of economic efficiency in thermal power plants

    International Nuclear Information System (INIS)

    Marukhyan, V.Z.; Elbakyan, S.H.

    2017-01-01

    Taking into account the input of carbon dioxide as a greenhouse gas in the global warming process, the technological solutions of its capturing, and the implementation possibilities in environmentally safe thermal power plants are considered. In power plants equipped with effective systems for cleaning the fuel gas and the coal gasification, the influence of the CO 2 reduction and realization of quotes on the indices of economic efficiency is estimated

  14. Evaluation of carbon dioxide emission control strategies in New York State

    International Nuclear Information System (INIS)

    Morris, S.C.; Lee, J.; Goldstein, G.; Hill, D.

    1992-01-01

    A MARKAL model was developed for the State of New York. It represents the state's energy system as a set of typical technologies for generating, converting, and using energy as it evolves over a 45-year period. NYMARKAL was applied here in demonstration analyses to explore strategies to reduce CO 2 emissions. NYMARKAL was installed at the State Energy Office and in the Offices of the New York Power Pool. Staff members from both organizations and other state agencies were trained in its use. Example scenarios showed that it is more difficult and more expensive to reduce carbon emissions in New York State than in the United States as a whole. Were a common carbon tax instituted, it would have less effect in New York and most carbon emissions reduction would take place elsewhere in the country where it is more cost-effective. Alternatively, were all states required to reduce CO 2 emission an equal percentage (say by 20%), the cost per unit emissions reduction to New York would be much greater than in the rest of the country

  15. Report of the Carbon Dioxide Committee II

    International Nuclear Information System (INIS)

    1994-01-01

    The Carbon Dioxide Committee was given the task of preparing a suggestion of the acts aimed at reducing the greenhouse gas emissions and increasing the sinks of carbon in Finland. Emissions of all greenhouse gases were in 1990 80 million tons. calculated as carbon dioxide. The carbon dioxide emissions were about 58 million tons of the total. The increase of forest resources binds carbon from the atmosphere and reduces thereby net emissions of Finland at present by nearly 30 million tons of carbon dioxide. Carbon dioxide emissions will grow during the next decades, unless strong measures to control them will not be taken. As a result of the Commissions examination, acts will be needed both in the production of energy and in its consumption. Emissions can be reduced by replacing fossil fuels with nuclear energy, bioenergy and other renewable energy sources. Saving of energy and improvement of energy efficiency will limit carbon dioxide emissions. The Commission has made suggestions both to change the structure of energy production and to control the consumption of energy. (orig.)

  16. 46 CFR 97.37-9 - Carbon dioxide alarm.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Carbon dioxide alarm. 97.37-9 Section 97.37-9 Shipping... Markings for Fire and Emergency Equipment, Etc. § 97.37-9 Carbon dioxide alarm. (a) All carbon dioxide alarms shall be conspicuously identified: “WHEN ALARM SOUNDS—VACATE AT ONCE. CARBON DIOXIDE BEING...

  17. 46 CFR 78.47-9 - Carbon dioxide alarm.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Carbon dioxide alarm. 78.47-9 Section 78.47-9 Shipping... and Emergency Equipment, Etc. § 78.47-9 Carbon dioxide alarm. (a) All carbon dioxide alarms shall be conspicuously identified: “WHEN ALARM SOUNDS—VACATE AT ONCE. CARBON DIOXIDE BEING RELEASED.” (b) [Reserved] ...

  18. 46 CFR 169.732 - Carbon dioxide alarm.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Carbon dioxide alarm. 169.732 Section 169.732 Shipping... Control, Miscellaneous Systems, and Equipment Markings § 169.732 Carbon dioxide alarm. Each carbon dioxide alarm must be conspicuously identified: “WHEN ALARM SOUNDS—VACATE AT ONCE. CARBON DIOXIDE BEING RELEASED.” ...

  19. 46 CFR 196.37-9 - Carbon dioxide alarm.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Carbon dioxide alarm. 196.37-9 Section 196.37-9 Shipping... Markings for Fire and Emergency Equipment, etc. § 196.37-9 Carbon dioxide alarm. (a) All carbon dioxide alarms shall be conspicuously identified: “WHEN ALARM SOUNDS—VACATE AT ONCE. CARBON DIOXIDE BEING...

  20. 46 CFR 108.627 - Carbon dioxide alarm.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Carbon dioxide alarm. 108.627 Section 108.627 Shipping... EQUIPMENT Equipment Markings and Instructions § 108.627 Carbon dioxide alarm. Each carbon dioxide alarm must be identified by marking: “WHEN ALARM SOUNDS VACATE AT ONCE. CARBON DIOXIDE BEING RELEASED” next to...

  1. Carbon dioxide: making the right connection

    African Journals Online (AJOL)

    This highlights safety issues concerning pipeline provision of carbon dioxide, and that it is of utmost ... capnograph sample line, gas analysis unit, water trap and soda .... The heat generated by the chemical reaction between soda lime.

  2. integrated vertical photobioreactor system for carbon dioxide

    African Journals Online (AJOL)

    Astri Nugroho

    2013-07-02

    Jul 2, 2013 ... efficient system for converting carbon dioxide (CO2) into biomass. The use of ... often been thought to achieve the most efficient mixing and the best ... such process a photobioreactor is designed. Photobioreactor is a device ...

  3. Supercritical carbon dioxide hop extraction

    Directory of Open Access Journals (Sweden)

    Pfaf-Šovljanski Ivana I.

    2005-01-01

    Full Text Available The hop of Magnum cultivar was extracted using supercritical carbon dioxide (SFE-as extractant. Extraction was carried out in the two steps: the first one being carried out at 150 bar and 40°C for 2.5 h (Extract A, and the second was the extraction of the same hop sample at 300 bar and 40°C for 2.5 h (Extract B. Extraction kinetics of the system hop-SFE-CO2 was investigated. Two of four most common compounds of hop aroma (α-humulene and β-caryophyllene were detected in Extract A. Isomerised α-acids and β-acids were detected too. a-Acid content in Extract B was high (that means it is a bitter variety of hop. Mathematical modeling using empirical model characteristic time model and simple single sphere model has been performed on Magnum cultivar extraction experimental results. Characteristic time model equations, best fitted experimental results. Empirical model equation, fitted results well, while simple single sphere model equation poorly approximated the results.

  4. Evaluation of technologies for the reduction of emissions and removal of carbon dioxide

    International Nuclear Information System (INIS)

    Daun, M.

    1993-01-01

    Aim of this work is the detailed and transparent evaluation of the technologies in question for the reduction of CO2 concentrations in the atmosphere and for CO2 removal. For this purpose it is of particular importance to differentiate between the technically possible and the economically thinkable or the ecologically efficient by taking into account the particular conditions in the FRG (West and East German states). Based on the analysis of CO2 flows in the FRG energy conversion technologies in the areas power generation, road traffic and supply of households and small consumers with heat which emit together more than 80% of the total amount of CO2 are chosen for the comparative evaluation. On the basis of a comparative system-analytical evaluation of individual measures a demand-orientated consumption, emission and cost model can be established for the areas power generation, low-temperature heat and road traffic. The characteristic parameters determined in the evaluations serve as basis for such a model. If this model is conceived in a way that also developments in time can be shown it is possible to find out in scenario calculations to which extent these new technologies can contribute in future to a cost-effective reduction of CO2 emissions. The investigation period for the development in time of CO2 emission in the areas mentioned above was chosen to be 25 years (1990-2015). (orig./KW) [de

  5. Extraction of Uranium Using Nitrogen Dioxide and Carbon Dioxide for Spent Fuel Reprocessing

    Energy Technology Data Exchange (ETDEWEB)

    Kayo Sawada; Daisuke Hirabayashi; Youichi Enokida [EcoTopia Science Institute, Nagoya University, Nagoya, 464-8603 (Japan)

    2008-07-01

    For the reprocessing of spent nuclear fuels, a new method to extract actinides from spent fuel using highly compressed gases, nitrogen dioxide and carbon dioxide was proposed. Uranium extraction from broken pieces, whose average grain size was 5 mm, of uranium dioxide pellet with nitrogen dioxide and carbon dioxide was demonstrated in the present study. (authors)

  6. Chemical, procedural and economical evaluation of carbon dioxide as feedstock in the chemical industry

    International Nuclear Information System (INIS)

    Otto, Alexander

    2015-01-01

    The utilisation of CO 2 as feedstock in the chemical industry represents an alternative to the geological storage, which is legally limited and socially debated. Generally, scientific publications about the utilisation of CO 2 in chemical reactions typically address the feasibility of the syntheses without paying attention to the CO 2 reduction potential or the economy in contrast to the conventional process of production. The aim of this doctoral thesis is to identify chemical reactions with CO 2 as feedstock, which have the potential to reduce CO 2 emissions. These reactions are evaluated concerning the industrial realization, CO 2 balance and economy compared to the conventional processes. To achieve this, 123 reactions from the literature were collected and evaluated with the help of selection criteria developed specifically for this application. The criteria consider both, the quantitative potential to reduce CO 2 and possible economical interests in these reactions. Additional to the process of the evaluation of the reactions, a CO 2 reduction potential of 1.33 % of the greenhouse gas emissions within the European Union could be calculated. For the chemicals formic acid, oxalic acid, formaldehyde, methanol, urea and dimethyl ether, which most fully satisfy the selection criteria, a direct comparison of the CO 2 based process with the conventional process is performed. By literature data, process designs, and simulations, it has been shown that the highest reductions of CO 2 emissions can be achieved for methanol with 1.43 kg CO2 /kg MeOH and dimethyl ether with 2.17 kg CO2 /kg DME , but only with the assumption that the necessary hydrogen for the CO 2 based reaction is produced by electrolysis operated with renewable energy. Overall, the CO 2 based production processes of methanol and dimethyl ether could reduce 0.059 % of the greenhouse gas emissions of the European Union (EU) if all conventional processes are substituted in the EU. Finally, for the CO 2

  7. Experimental performance evaluation for a carbon dioxide light commercial cooling application under transcritical and subcritical conditions

    International Nuclear Information System (INIS)

    Boccardi, G.; Calabrese, N.; Celata, G.P.; Mastrullo, R.; Mauro, A.W.; Perrone, A.; Trinchieri, R.

    2013-01-01

    CO 2 is one of the most interesting non toxic, nor flammable, low GWP natural fluid to be used in applications with a large direct contribution to global warming, such as vending machines. In this paper the results of an experimental investigation on a small capacity, air-forced refrigerating plant working with CO 2 are presented. The air inlet temperatures at gas cooler and evaporator were varied between 16 °C and 31 °C and between −25 °C and 25 °C, respectively, to cover the range of temperatures under conditions typical of commercial refrigeration, during quasi-steady operation. The thermodynamic analysis of the system performance was carried on varying independently the pressure at the gas cooler, by overfeeding the liquid receiver to point out the effect of refrigerant charge. The results allow to describe the performance of the system in a map varying the boundary conditions; at the same time the corresponding variations of the thermodynamic cycle, the COP and the mass flow rate are reported. -- Highlights: ► A light commercial refrigerating plant working with CO 2 was tested in order to evaluate its performance. ► 71 experimental points were collected varying the flow rates, the temperatures of air sources and the refrigerant charge. ► Mass flow rate, cooling capacity, electrical power and COP were evaluated as a function of pressures and superheating. ► The segregate influence of each operating parameter on each performance indicator was calculated. ► A map of plant performance as a function of air source temperatures is reported

  8. Computational evaluation of metal-organic frameworks for carbon dioxide capture

    Science.gov (United States)

    Yu, Jiamei

    Metal-organic frameworks (MOFs), a new class of porous solids comprised of metal-containing nodes linked by organic ligands, have become promising materials for gas separations. In particular, their flexible chemistry makes them attractive for CO2 capture from flue gas streams in post-combustion plants. Although numerous efforts have been exerted on the investigation of MOFs for CO2 capture, the exploration of the effects from coexisting components present in very dilute proportions in flue gases is limited because of the experimental difficulty to determine the coadsorption of CO2 with trace components. In this regard, molecular simulations show superiority. In this study, molecular simulations are used to estimate the influence of impurities: water, O2, and SO2 on post-combustion CO2 capture in MOFs. Firstly, two MOFs with coordinatively unsaturated metal sites (CUMs), HKUST-1 and Mg-MOF-74 are explored. Increase of CO 2 adsorption is observed for hydrated HKUST-1; on the contrary, the opposite water adsorption behavior is observed in hydrated Mg-MOF-74, leading to decrease of CO2 adsorption. Further, water effects on CO 2 capture in M-HKUST1 (M = Mg, Zn, Co, Ni) are evaluated to test whether comparing the binding energy could be a general method to evaluate water effects in MOFs with CUMs. It is found that the method works well for Zn-, Co-, and Ni-HKUST1 but partially for Mg-HKUST1. In addition, the effects of O2 and SO2 on CO2 capture in MOFs are also investigated for the first time, showing that the effects of O2 may be negligible but SO2 has negative effects in the CO 2 capture process in HKUST-1 systems. Secondly, the influences of water on CO2 capture in three UiO-66 MOFs with functional groups, --NH2, --OH and --Br are explored, respectively. For UiO-66-NH2 and -OH, the presence of water lowers CO2 adsorption significantly; in contrast, water shows much smaller effects in UiO-66-Br. Moreover, the presence of SO 2 decreases water adsorption but enhances CO

  9. Optimization and evaluation of foxtail millet (Setaria italica bran oil by supercritical carbon dioxide extraction

    Directory of Open Access Journals (Sweden)

    Pang, M.

    2015-12-01

    Full Text Available A Box-Behnken central composite design combined with the response surface methodology (RSM was used to optimize the parameters of a supercritical fluid extraction (SFE of foxtail millet bran oil (FMBO. Results showed that a maximum oil yield of 7.97% was achieved under the optimal conditions with an extracting pressure of 30.03MPa, extracting temperature of 47.93 °C; and an extraction time of 2.3 h. The quality of the oil obtained from SFE and solvent extraction (SE was evaluated by proximate analysis to include physicochemical properties, fatty acids and sterol compounds. The FBMO obtained from SFE showed a much lower phospholipid (0.188 mg/g content and a preferable color compared to the oil from SE, while it contained a higher content of total sterols, 1.55%. The thermal gravimetric analysis results showed one major regime of weight loss over a temperature range of 300–500 °C. The results show that FBMO obtained by SFE can be a promising nutritional source for food fortification and is understood to have more potentially healthy biological properties.Un diseño Box-Behnken combinado con la metodología de superficie de respuesta (RSM se usó para optimizar los parámetros de extracción mediante fluido supercrítico (SFE de aceite de salvado de mijo (FMBO. Los resultados mostraron que un rendimiento máximo de extracción de aceite del 7,97% se logró en las condiciones óptimas correspondientes a una presión de 30.03MPa, una temperatura 47.93 °C y un tiempo 2,3H. Además, se evaluó la calidad del aceite obtenido por SFE y mediante extracción con disolvente (SE a partir de un análisis proximal que incluye propiedades fisicoquímicas, ácidos grasos y esteroles. El aceite de FBMO obtenido mediante SFE mostró un contenido mucho menor de fosfolípidos (0.188 mg/g y un color mas aceptable que el aceite de la SE, mientras que contenía un mayor contenido de esteroles totales: 1,55%. El resultado del análisis térmico gravimétrico mostr

  10. Carbon Dioxide Emission Evaluation of Porous Vegetation Concrete Blocks for Ecological Restoration Projects

    Directory of Open Access Journals (Sweden)

    Hwang-Hee Kim

    2017-02-01

    Full Text Available The purpose of this study is to determine the mix proportions that can minimize CO2 emissions while satisfying the target performance of porous vegetation concrete. The target performance of porous vegetation concrete was selected as compressive strength (>15 MPa and void ratio (>25%. This study considered the use of reinforcing fiber and styrene butadiene (SB latex to improve the strength of porous vegetation concrete, as well as the use of blast furnace slag aggregate to improve the CO2 emissions-reducing effect, and analyzed and evaluated the influence of fiber reinforcing, SB latex, and blast furnace slag aggregate on the compressive strength and CO2 emissions of porous vegetation concrete. The CO2 emissions of the raw materials were highest for cement, followed by aggregate, SB latex, and fiber. Blast furnace slag aggregate showed a 30% or more CO2 emissions-reducing effect versus crushed aggregate, and blast furnace slag cement showed a 78% CO2 emissions-reducing effect versus Portland cement. The CO2 emissions analyses for each raw material showed that the CO2 emissions during transportation were highest for the aggregate. Regarding CO2 emissions in each production stage, the materials stage produced the highest CO2 emissions, while the proportion of CO2 emissions in the transportation stage for each raw material, excluding fiber, were below 3% of total emissions. Use of blast furnace slag aggregate in porous vegetation concrete produced CO2 emissions-reducing effects, but decreased its compressive strength. Use of latex in porous vegetation concrete improved its compressive strength, but also increased CO2 emissions. Thus, it is appropriate to use latex in porous vegetation concrete to improve its strength and void ratio, and to use a blast furnace slag aggregate replacement ratio of 40% or less.

  11. Evaluation of Carbon Dioxide Capture From Existing Coal Fired Plants by Hybrid Sorption Using Solid Sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Benson, Steven [Univ. of North Dakota, Grand Forks, ND (United States); Srinivasachar, Srivats [Envergex LLC, Sturbridge, MA (United States); Laudal, Daniel [Univ. of North Dakota, Grand Forks, ND (United States); Browers, Bruce [Barr Engineering, Minneapolis, MN (United States)

    2014-12-31

    A novel hybrid solid sorbent technology for CO₂ capture and separation from coal combustion-derived flue gas was evaluated. The technology – Capture of CO₂ by Hybrid Sorption (CACHYS™) – is a solid sorbent technology based on the following ideas: 1) reduction of energy for sorbent regeneration, 2) utilization of novel process chemistry, 3) contactor conditions that minimize sorbent-CO₂ heat of reaction and promote fast CO₂ capture, and 4) low-cost method of heat management. This report provides key information developed during the course of the project that includes sorbent performance, energy for sorbent regeneration, physical properties of the sorbent, the integration of process components, sizing of equipment, and overall capital and operational cost of the integrated CACHYS™ system. Seven sorbent formulations were prepared and evaluated at the lab-scale for energy requirements and CO₂ capture performance. Sorbent heat of regeneration ranged from 30-80 kJ/mol CO₂ and was found to be dependent on process conditions. Two sorbent formulations (designated HCK-4 & HCK-7) were down-selected for additional fixed-bed testing. Additional testing involved subjecting the sorbents to 100 continuous cycles in the fixed-bed reactor to determine performance as a function of time. The working capacity achieved for HCK-4 sorbent ranged from 5.5-8.0 g CO₂/100 g sorbent, while the HCK-7 typically ranged from 8.0-10.0 g CO₂/100 g sorbent. Overall, there was no deterioration in capacity with continuous cycling for either sorbent. The CACHYS™ bench-scale testing system designed and fabricated under this award consists of a dual circulating fluidized-bed adsorber and a moving-bed regenerator. The system takes a flue gas slipstream from the University of North Dakota’s coal-fired steam plant. Prior to being sent to the adsorber, the flue gas is scrubbed to remove SO₂ and particulate. During parametric testing of the adsorber, CO₂ capture achieved using

  12. Graphite suspension in carbon dioxide

    International Nuclear Information System (INIS)

    Roche, R.

    1965-01-01

    Since 1963 the Atomic Division of SNECMA has been conducting, under a contract with the CEA, an experimental work with a two-component fluid comprised of carbon dioxide and small graphite particles. The primary purpose was the determination of basic engineering information pertaining to the stability and the flowability of the suspension. The final form of the experimental loop consists mainly of the following items: a light-phase compressor, a heavy-phase pump, an electrical-resistance type heater section, a cooling heat exchanger, a hairpin loop, a transparent test section and a separator. During the course of the testing, it was observed that the fluid could be circulated quite easily in a broad range of variation of the suspension density and velocity - density from 30 to 170 kg/m 3 and velocity from 2 to 24 m/s. The system could be restarted and circulation maintained without any difficulty, even with the heavy-phase pump alone. The graphite did not have a tendency to pack or agglomerate during operation. No graphite deposition was observed on the wall of the tubing. A long period run (250 hours) has shown the evolution of the particle dimensions. Starting with graphite of surface area around 20 m 2 /g (graphite particles about 1 μ), the powder surface area reaches an asymptotic value of 300 m 2 /g (all the particles less than 0.3 μ). Moisture effect on flow stability, flow distribution between two parallel channels, pressure drop in straight tubes, recompression ratio in diffusers were also investigated. (author) [fr

  13. Evaluation of submarine atmospheres: effects of carbon monoxide, carbon dioxide and oxygen on general toxicology, neurobehavioral performance, reproduction and development in rats. I. Subacute exposures.

    Science.gov (United States)

    Hardt, Daniel J; James, R Arden; Gut, Chester P; McInturf, Shawn M; Sweeney, Lisa M; Erickson, Richard P; Gargas, Michael L

    2015-02-01

    The inhalation toxicity of submarine contaminants is of concern to ensure the health of men and women aboard submarines during operational deployments. Due to a lack of adequate prior studies, potential general, neurobehavioral, reproductive and developmental toxicity was evaluated in male and female rats exposed to mixtures of three critical submarine atmospheric components: carbon monoxide (CO) and carbon dioxide (CO2; levels elevated above ambient), and oxygen (O2; levels decreased below ambient). In a 14-day, 23 h/day, whole-body inhalation study of exposure to clean air (0.4 ppm CO, 0.1% CO2 and 20.6% O2), low-dose, mid-dose and high-dose gas mixtures (high dose of 88.4 ppm CO, 2.5% CO2 and 15.0% O2), no adverse effects on survival, body weight or histopathology were observed. Reproductive, developmental and neurobehavioral performance were evaluated after a 28-day exposure in similar atmospheres. No adverse effects on estrus phase, mating, gestation or parturition were observed. No developmental or functional deficits were observed in either exposed parents or offspring related to motor activity, exploratory behavior or higher-level cognitive functions (learning and memory). Only minimal effects were discovered in parent-offspring emotionality tests. While statistically significant increases in hematological parameters were observed in the offspring of exposed parents compared to controls, these parameters remained within normal clinical ranges for blood cells and components and were not considered adverse. In summary, subacute exposures to elevated concentrations of the submarine atmosphere gases did not affect the ability of rats to reproduce and did not appear to have any significant adverse health effects.

  14. Challenges in Evaluating Relationships Between Quantitative Data (Carbon Dioxide) and Qualitative Data (Self-Reported Visual Changes)

    Science.gov (United States)

    Mendez, C. M.; Foy, M.; Mason, S.; Wear, M. L.; Meyers, V.; Law, J.; Alexander, D.; Van Baalen, M.

    2014-01-01

    Understanding the nuances in clinical data is critical in developing a successful data analysis plan. Carbon dioxide (CO2) data are collected on board the International Space Station (ISS) in a continuous stream. Clinical data on ISS are primarily collected via conversations between individual crewmembers and NASA Flight Surgeons during weekly Private Medical Conferences (PMC). Law, et.al, 20141 demonstrated a statistically significant association between weekly average CO2 levels on ISS and self-reported headaches over the reporting period from March 14, 2001 to May 31, 2012. The purpose of this analysis is to describe the evaluation of a possible association between visual changes and CO2 levels on ISS and to discuss challenges in developing an appropriate analysis plan. METHODS & PRELIMINARY RESULTS: A first analysis was conducted following the same study design as the published work on CO2 and self-reported headaches1; substituting self-reported changes in visual acuity in place of self-reported headaches. The analysis demonstrated no statistically significant association between visual impairment characterized by vision symptoms self-reported during PMCs and ISS average CO2 levels over ISS missions. Closer review of the PMC records showed that vision outcomes are not well-documented in terms of clinical severity, timing of onset, or timing of resolution, perhaps due to the incipient nature of vision changes. Vision has been monitored in ISS crewmembers, pre- and post-flight, using standard optometry evaluations. In-flight visual assessments were limited early in the ISS program, primarily consisting of self-perceived changes reported by crewmembers. Recently, on-orbit capabilities have greatly improved. Vision data ranges from self-reported post-flight changes in visual acuity, pre- to postflight changes identified during fundoscopic examination, and in-flight progression measured by advanced on-orbit clinical imaging capabilities at predetermined testing

  15. Reaction of titanium polonides with carbon dioxide

    International Nuclear Information System (INIS)

    Abakumov, A.S.; Malyshev, M.L.; Reznikova, N.F.

    1987-01-01

    It has been ascertained that heating titanium and tantalum in carbon dioxide to temperatures of 500 or 800 0 C alters the composition of the gas phase, causing the advent of carbon monoxide and lowering the oxygen content. Investigation of the thermal stability of titanium polonides in a carbon dioxide medium has shown that titanium mono- and hemipolonides are decomposed at temperatures below 350 0 C. The temperature dependence of the vapor pressure of polonium produced in the decomposition of these polonides in a carbon dioxide medium have been determined by a radiotensimetric method. The enthalpy of the process, calculated from this relationship, is close to the enthalpy of vaporization of elementary polonium in vacuo

  16. Method for Extracting and Sequestering Carbon Dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Rau, Gregory H.; Caldeira, Kenneth G.

    2005-05-10

    A method and apparatus to extract and sequester carbon dioxide (CO2) from a stream or volume of gas wherein said method and apparatus hydrates CO2, and reacts the resulting carbonic acid with carbonate. Suitable carbonates include, but are not limited to, carbonates of alkali metals and alkaline earth metals, preferably carbonates of calcium and magnesium. Waste products are metal cations and bicarbonate in solution or dehydrated metal salts, which when disposed of in a large body of water provide an effective way of sequestering CO2 from a gaseous environment.

  17. Apparatus for extracting and sequestering carbon dioxide

    Science.gov (United States)

    Rau, Gregory H [Castro Valley, CA; Caldeira, Kenneth G [Livermore, CA

    2010-02-02

    An apparatus and method associated therewith to extract and sequester carbon dioxide (CO.sub.2) from a stream or volume of gas wherein said apparatus hydrates CO.sub.2 and reacts the resulting carbonic acid with carbonate. Suitable carbonates include, but are not limited to, carbonates of alkali metals and alkaline earth metals, preferably carbonates of calcium and magnesium. Waste products are metal cations and bicarbonate in solution or dehydrated metal salts, which when disposed of in a large body of water provide an effective way of sequestering CO.sub.2 from a gaseous environment.

  18. Evaluating the impacts of new walking and cycling infrastructure on carbon dioxide emissions from motorized travel: a controlled longitudinal study

    Science.gov (United States)

    Brand, Christian; Goodman, Anna; Ogilvie, David

    2015-01-01

    Walking and cycling is widely assumed to substitute for at least some motorized travel and thereby reduce energy use and carbon dioxide (CO2) emissions. While the evidence suggests that a supportive built environment may be needed to promote walking and cycling, it is unclear whether and how interventions in the built environment that attract walkers and cyclists may reduce transport CO2 emissions. Our aim was therefore to evaluate the effects of providing new infrastructure for walking and cycling on CO2 emissions from motorised travel. A cohort of 1849 adults completed questionnaires at baseline (2010) and one-year follow-up (2011), before and after the construction of new high-quality routes provided as part of the Sustrans Connect2 programme in three UK municipalities. A second cohort of 1510 adults completed questionnaires at baseline and two-year follow-up (2012). The participants reported their past-week travel behaviour and car characteristics from which CO2 emissions by mode and purpose were derived using methods described previously. A set of exposure measures of proximity to and use of the new routes were derived. Overall transport CO2 emissions decreased slightly over the study period, consistent with a secular trend in the case study regions. As found previously the new infrastructure was well used at one- and two-year follow-up, and was associated with population-level increases in walking, cycling and physical activity at two-year follow-up. However, these effects did not translate into sizeable CO2 effects as neither living near the infrastructure nor using it predicted changes in CO2 emissions from motorised travel, either overall or disaggregated by journey purpose. This lack of a discernible effect on travel CO2 emissions are consistent with an interpretation that some of those living nearer the infrastructure may simply have changed where they walked or cycled, while others may have walked or cycled more but few, if any, may have substituted

  19. Evaluating the impacts of new walking and cycling infrastructure on carbon dioxide emissions from motorized travel: a controlled longitudinal study.

    Science.gov (United States)

    Brand, Christian; Goodman, Anna; Ogilvie, David

    2014-09-01

    Walking and cycling is widely assumed to substitute for at least some motorized travel and thereby reduce energy use and carbon dioxide (CO 2 ) emissions. While the evidence suggests that a supportive built environment may be needed to promote walking and cycling, it is unclear whether and how interventions in the built environment that attract walkers and cyclists may reduce transport CO 2 emissions. Our aim was therefore to evaluate the effects of providing new infrastructure for walking and cycling on CO 2 emissions from motorised travel. A cohort of 1849 adults completed questionnaires at baseline (2010) and one-year follow-up (2011), before and after the construction of new high-quality routes provided as part of the Sustrans Connect2 programme in three UK municipalities. A second cohort of 1510 adults completed questionnaires at baseline and two-year follow-up (2012). The participants reported their past-week travel behaviour and car characteristics from which CO 2 emissions by mode and purpose were derived using methods described previously. A set of exposure measures of proximity to and use of the new routes were derived. Overall transport CO 2 emissions decreased slightly over the study period, consistent with a secular trend in the case study regions. As found previously the new infrastructure was well used at one- and two-year follow-up, and was associated with population-level increases in walking, cycling and physical activity at two-year follow-up. However, these effects did not translate into sizeable CO 2 effects as neither living near the infrastructure nor using it predicted changes in CO 2 emissions from motorised travel, either overall or disaggregated by journey purpose. This lack of a discernible effect on travel CO 2 emissions are consistent with an interpretation that some of those living nearer the infrastructure may simply have changed where they walked or cycled, while others may have walked or cycled more but few, if any, may have

  20. Carbon dioxide problem: solution by technical countermeasures

    Energy Technology Data Exchange (ETDEWEB)

    Bach, W

    1978-02-15

    A rough assessment indicates that anthropogenic influences might raise the mean global surface temperature by 0.8 to 1.2 C in 2000 AD and by 2 to 4 C in 2050 AD. The rapidly increasing levels of atmospheric carbon dioxide are largely responsible for this warming trend. A variety of measures for the reduction of carbon dioxide emissions is presented. One promising approach is to work out a world-wide energy mix that can counteract a temperature increase. (In German)

  1. Environmental effects of increased atmospheric carbon dioxide

    International Nuclear Information System (INIS)

    Soon, W.; Baliunas, S.L.; Robinson, A.B.; Robinson, Z.W.

    1999-01-01

    A review of the literature concerning the environmental consequences of increased levels of atmospheric carbon dioxide leads to the conclusion that increases during the 20th century have produced no deleterious effects upon global climate or temperature. Increased carbon dioxide has, however, markedly increased plant growth rates as inferred from numerous laboratory and field experiments. There is no clear evidence, nor unique attribution, of the global effects of anthropogenic CO 2 on climate. Meaningful integrated assessments of the environmental impacts of anthropogenic CO 2 are not yet possible because model estimates of global and regional climate changes on interannual, decadal and centennial timescales remain highly uncertain.(author)

  2. Carbon dioxide and the greenhouse effect: an unresolved problem

    Energy Technology Data Exchange (ETDEWEB)

    Smith, I M

    1978-01-01

    This paper evaluates current scientific literature concerned with the accumulation of carbon dioxide in the atmosphere. The extent and possible causes of natural variations in global climate are outlined as a background to potential variations due to human activity. Estimates are given on relative contributions of carbon dioxide to the atmosphere due to fossil fuel combustion, deforestation and other land modifications. The possibility of a rise in global temperature as a result of increasing the amount of carbon dioxide in the atmosphere is discussed including model predictions, natural factors which could compensate for or emphasize a warming effect, and the implications if extensive warming actually occurred. Carbon dioxide disposal is discussed but there appears to be no practicable long-term means of accomplishing this. It is concluded that there is no evidence of a rise in global temperature due to carbon dioxide at present. Predictions, which involve a high degree of uncertainty, indicate that the global temperature could rise appreciably in the next century. An increase in precipitation rate is also expected.

  3. Carbon dioxide and the 'greenhouse effect': an unresolved problem

    Energy Technology Data Exchange (ETDEWEB)

    Smith, I

    1978-01-01

    This executive review evaluates current scientific literature concerned with the accumulation of carbon dioxide in the atmosphere. The extent and possible causes of natural variations in global climate are outlined as a background to potential variations due to human activity. Estimates are given on relative contributions of carbon dioxide to the atmosphere due to fossil fuel combustion, deforestation and other land modifications. The possibility of a rise in global temperature as a result of increasing the amount of carbon dioxide in the atmosphere is dicusssed including model predictions, natural factors which could compensate for or emphasize a warming effect, and the implications if extensive warming actually occurred. Carbon dioxide disposal is discussed, but there appears to be no practicable long-term means of accomplishing this. It is concluded that there is no evidence of a rise in global temperature due to carbon dioxide at present. Predictions, which involve a high degree of uncertainty, indicate that the global temperature could rise appreciably in the next century. An increase in precipitation rate is also expected. If these changes result in a redistribution of climatic zones, there may be problems in adapting agricultural belts in some regions. Complete melting of all the ice sheets would take several millenia. A partial melting of continental ice sheets would not necessarily occur in view of the increase in precipitation rates, but if it did, there would be a rise in sea level of a few metres. Melting of the Arctic sea ice would affect climate, but not sea level.

  4. Catalyst retention in continuous flow with supercritical carbon dioxide

    NARCIS (Netherlands)

    Stouten, S.C.; Noel, T.; Wang, Q.; Hessel, V.

    2014-01-01

    This review discusses the retention of organometallic catalysts in continuous flow processes utilizing supercritical carbon dioxide. Due to its innovative properties, supercritical carbon dioxide offers interesting possibilities for process intensification. As a result of safety and cost

  5. Evaluation of refrigerating and air-conditioning technologies in heat cascading systems under the carbon dioxide emissions constraint: the proposal of the energy cascade balance table

    International Nuclear Information System (INIS)

    Shimazaki, Yoichi

    2003-01-01

    The aim of this study was to evaluate the refrigerating and air-conditioning technologies in cases of introducing both heat cascading systems and thermal recycling systems in industries located around urban areas. It is necessary to introduce heat cascading systems in the industrial sector in Japan to reduce carbon dioxide emissions. The concept of heat cascading is the multi-stage use of thermal energy by temperature level. This paper introduces three energy policies for introducing the heat cascading systems. The author develops an energy cascade model based on linear programming so as to minimize the total system costs with carbon taxes. Five cases are investigated. Carbon dioxide emission constraints result in the enhancement of heat cascading, where high temperature heat is supplied for process heating while low temperature heat is shifted to refrigeration. It was found that increasing the amount of garbage combustion waste heat could reduce electric power for the turbo compression refrigerator by promoting waste heat driven ammonia absorption refrigerator. In addition, this study proposes an energy cascade balance table with respect to the temperature level

  6. Human population and carbon dioxide

    International Nuclear Information System (INIS)

    Schaffer, W.M.

    2008-01-01

    A recently proposed model of human population and carbon utilization is reviewed. Depending on parameter values, one of three possible long-term outcomes is obtained. (1) Atmospheric carbon, (CO 2 ) atm , and human populations equilibrate at positive values. (2) The human population stabilizes, while (CO 2 ) atm increases without bound. (3) The human population goes extinct and atmospheric carbon declines to 0. The final possibility is qualitatively compatible with both 'consensus' views of climate change and the opinions of those who are more impressed with the manifestly adverse consequences of carbon-mitigation to human reproduction and survival

  7. Carbon dioxide capture and air quality

    NARCIS (Netherlands)

    Horssen, A. van; Ramirez, C.A.; Harmelen, T. van; Koornneef, J.

    2011-01-01

    Carbon dioxide (CO2) is one of the most important greenhouse gases (GHG). The most dominant source of anthropogenic CO2 contributing to the rise in atmospheric concentration since the industrial revolution is the combustion of fossil fuels. These emissions are expected to result in global climate

  8. Electrocatalytic carbon dioxide reduction - a mechanistic study

    NARCIS (Netherlands)

    Schouten, Klaas Jan Schouten

    2013-01-01

    This thesis presents new insights into the reduction of carbon dioxide to methane and ethylene on copper electrodes. This electrochemical process has great potential for the storage of surplus renewable electrical energy in the form of hydrocarbons. The research described in this thesis focuses on

  9. Carbon dioxide enhances fragility of ice crystals

    International Nuclear Information System (INIS)

    Qin Zhao; Buehler, Markus J

    2012-01-01

    Ice caps and glaciers cover 7% of the Earth, greater than the land area of Europe and North America combined, and play an important role in global climate. The small-scale failure mechanisms of ice fracture, however, remain largely elusive. In particular, little understanding exists about how the presence and concentration of carbon dioxide molecules, a significant component in the atmosphere, affects the propensity of ice to fracture. Here we use atomic simulations with the first-principles based ReaxFF force field capable of describing the details of chemical reactions at the tip of a crack, applied to investigate the effects of the presence of carbon dioxide molecules on ice fracture. Our result shows that increasing concentrations of carbon dioxide molecules significantly decrease the fracture toughness of the ice crystal, making it more fragile. Using enhanced molecular sampling with metadynamics we reconstruct the free energy landscape in varied chemical microenvironments and find that carbon dioxide molecules affect the bonds between water molecules at the crack tip and decrease their strength by altering the dissociation energy of hydrogen bonds. In the context of glacier dynamics our findings may provide a novel viewpoint that could aid in understanding the breakdown and melting of glaciers, suggesting that the chemical composition of the atmosphere can be critical to mediate the large-scale motion of large volumes of ice.

  10. Diiodination of Alkynes in supercritical Carbon dioxide

    Institute of Scientific and Technical Information of China (English)

    李金恒; 谢叶香; 尹笃林; 江焕峰

    2003-01-01

    A general,green and efficient method for the synthesis of transdiiodoalkenes in CO2(sc) has been developed.Trans-diiodoalkenes were obtained stereospecifically in quantitative yields via diiodination of both electron-rich and electron-deficient alkynes in the presence of KI,Ce(SO4)2 and water in supercritical carbon dioxide [CO2(sc)]at 40℃.

  11. Tourism Transport, Technology, and Carbon Dioxide Emissions

    NARCIS (Netherlands)

    Peeters, P.M.

    2010-01-01

    Technological development from horse-drawn carriages to the new Airbus A380 has led to a remarkable increase in both the capacity and speed of tourist travel. This development has an endogenous systemic cause and will continue to increase carbon dioxide emissions/energy consumption if left

  12. Carbon dioxide sensing with sulfonated polyaniline

    NARCIS (Netherlands)

    Doan, D.C.T.; Ramaneti, R.; Baggerman, J.; Bent, van der J.; Marcelis, A.T.M.; Tong, H.D.; Rijn, van C.J.M.

    2012-01-01

    The use of polyaniline and especially sulfonated polyaniline (SPAN) is explored for sensing carbon dioxide (CO2) at room temperature. Frequency-dependent AC measurements were carried out to detect changes in impedance of the polymer, drop casted on interdigitated electrodes, when exposed to CO2 gas.

  13. Conductive polymers for carbon dioxide sensing

    NARCIS (Netherlands)

    Doan, T.C.D.

    2012-01-01

    Augmented levels of carbon dioxide (CO2) in greenhouses stimulate plant growth through photosynthesis. Wireless sensor networks monitoring CO2 levels in greenhouses covering large areas require preferably low power sensors to minimize energy consumption. Therefore, the main

  14. Transport properties of supercritical carbon dioxide

    NARCIS (Netherlands)

    Lavanchy, F.; Fourcade, E.; de Koeijer, E.A.; Wijers, J.G.; Meyer, T.; Keurentjes, J.T.F.; Kemmere, M.F.; Meyer, T.

    2005-01-01

    Recently, supercritical fluids have emerged as more sustainable alternatives for the organic solvents often used in polymer processes. This is the first book emphasizing the potential of supercritical carbon dioxide for polymer processes from an engineering point of view. It develops a

  15. Removing carbon dioxide from a stationary source through co ...

    African Journals Online (AJOL)

    Except temperature of solvent, all study variables showed strong relation with the amount of carbon dioxide absorbed (with a P-value < 0.05). Uniquely, this study has evaluated the potential for sodium bicarbonate production from the CO2 absorbed using gravimetric analysis. It is also possible to recover over 28% crystal ...

  16. Formic Acid Manufacture: Carbon Dioxide Utilization Alternatives

    Directory of Open Access Journals (Sweden)

    Marta Rumayor

    2018-06-01

    Full Text Available Carbon dioxide (CO2 utilization alternatives for manufacturing formic acid (FA such as electrochemical reduction (ER or homogeneous catalysis of CO2 and H2 could be efficient options for developing more environmentally-friendly production alternatives to FA fossil-dependant production. However, these alternatives are currently found at different technological readiness levels (TRLs, and some remaining technical challenges need to be overcome to achieve at least carbon-even FA compared to the commercial process, especially ER of CO2, which is still farther from its industrial application. The main technical limitations inherited by FA production by ER are the low FA concentration achieved and the high overpotentials required, which involve high consumptions of energy (ER cell and steam (distillation. In this study, a comparison in terms of carbon footprints (CF using the Life Cycle Assessment (LCA tool was done to evaluate the potential technological challenges assuring the environmental competitiveness of the FA production by ER of CO2. The CF of the FA conventional production were used as a benchmark, as well as the CF of a simulated plant based on homogeneous catalysts of CO2 and H2 (found closer to be commercial. Renewable energy utilization as PV solar for the reaction is essential to achieve a carbon-even product; however, the CF benefits are still negligible due to the enormous contribution of the steam produced by natural gas (purification stage. Some ER reactor configurations, plus a recirculation mode, could achieve an even CF versus commercial process. It was demonstrated that the ER alternatives could lead to lower natural resources consumption (mainly, natural gas and heavy fuel oil compared to the commercial process, which is a noticeable advantage in environmental sustainability terms.

  17. Metabolic effects of Carbon Dioxide (CO 2 ) insufflation during ...

    African Journals Online (AJOL)

    Metabolic effects of Carbon Dioxide (CO 2 ) insufflation during laparoscopic surgery: changes in pH, arterial partial Pressure of Carbon Dioxide (PaCo 2 ) and End Tidal Carbon Dioxide (EtCO 2 ) ... Respiratory adjustments were done for EtCO2 levels above 60mmHg or SPO2 below 92% or adverse haemodynamic changes.

  18. 27 CFR 24.319 - Carbon dioxide record.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Carbon dioxide record. 24..., DEPARTMENT OF THE TREASURY LIQUORS WINE Records and Reports § 24.319 Carbon dioxide record. A proprietor who uses carbon dioxide in still wine shall maintain a record of the laboratory tests conducted to...

  19. 27 CFR 26.222 - Still wines containing carbon dioxide.

    Science.gov (United States)

    2010-04-01

    ... carbon dioxide. 26.222 Section 26.222 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND... ISLANDS Formulas for Products From the Virgin Islands § 26.222 Still wines containing carbon dioxide. (a) General. Still wines may contain not more than 0.392 gram of carbon dioxide per 100 milliliters of wine...

  20. 27 CFR 26.52 - Still wines containing carbon dioxide.

    Science.gov (United States)

    2010-04-01

    ... carbon dioxide. 26.52 Section 26.52 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND... ISLANDS Formulas for Products From Puerto Rico § 26.52 Still wines containing carbon dioxide. (a) General. Still wines may contain not more than 0.392 gram of carbon dioxide per 100 milliliters of wine; except...

  1. Integrated Assessment of Carbon Dioxide Removal

    Science.gov (United States)

    Rickels, W.; Reith, F.; Keller, D.; Oschlies, A.; Quaas, M. F.

    2018-03-01

    To maintain the chance of keeping the average global temperature increase below 2°C and to limit long-term climate change, removing carbon dioxide from the atmosphere (carbon dioxide removal, CDR) is becoming increasingly necessary. We analyze optimal and cost-effective climate policies in the dynamic integrated assessment model (IAM) of climate and the economy (DICE2016R) and investigate (1) the utilization of (ocean) CDR under different climate objectives, (2) the sensitivity of policies with respect to carbon cycle feedbacks, and (3) how well carbon cycle feedbacks are captured in the carbon cycle models used in state-of-the-art IAMs. Overall, the carbon cycle model in DICE2016R shows clear improvements compared to its predecessor, DICE2013R, capturing much better long-term dynamics and also oceanic carbon outgassing due to excess oceanic storage of carbon from CDR. However, this comes at the cost of a (too) tight short-term remaining emission budget, limiting the model suitability to analyze low-emission scenarios accurately. With DICE2016R, the compliance with the 2°C goal is no longer feasible without negative emissions via CDR. Overall, the optimal amount of CDR has to take into account (1) the emission substitution effect and (2) compensation for carbon cycle feedbacks.

  2. Ocean uptake of carbon dioxide

    International Nuclear Information System (INIS)

    Peng, Tsung-Hung; Takahashi, Taro

    1993-01-01

    Factors controlling the capacity of the ocean for taking up anthropogenic C0 2 include carbon chemistry, distribution of alkalinity, pCO 2 and total concentration of dissolved C0 2 , sea-air pCO 2 difference, gas exchange rate across the sea-air interface, biological carbon pump, ocean water circulation and mixing, and dissolution of carbonate in deep sea sediments. A general review of these processes is given and models of ocean-atmosphere system based on our understanding of these regulating processes axe used to estimate the magnitude of C0 2 uptake by the ocean. We conclude that the ocean can absorb up to 35% of the fossil fuel emission. Direct measurements show that 55% Of C0 2 from fossil fuel burning remains in the atmosphere. The remaining 10% is not accounted for by atmospheric increases and ocean uptake. In addition, it is estimated that an amount equivalent to 30% of recent annual fossil fuel emissions is released into the atmosphere as a result of deforestation and farming. To balance global carbon budget, a sizable carbon sink besides the ocean is needed. Storage of carbon in terrestrial biosphere as a result of C0 2 fertilization is a potential candidate for such missing carbon sinks

  3. Evaluation the effect of breathing filters on end-tidal carbon dioxide during inferior abdominal surgery in infants and changes of tidal volume and respiratory rate needs for preventing of increasing end-tidal carbon dioxide.

    Science.gov (United States)

    Sajedi, Parvin; Abooei, Mohsen; Shafa, Amir; Karbalaei, Mahboobeh; Babaei, Atefeh

    2016-01-01

    The aim of this study was to prevent of increasing end-tidal carbon dioxide (ETCO 2) with changing of vital capacity and respiratory rate when using of birthing filter in infants. In a randomized clinical trial study, ninety-four infant' patients were studied in three groups. Basic values, such as peak inspiratory pressure, tidal volume, minute ventilation, respiratory rate, and partial pressure of ET CO 2 (PETCO 2 ) level had been evaluated after intubation, 10 min after intubation and 10 min after filter insertion. In the first group, patients only observed for changing in ETCO 2 level. In the second and the third groups, respiratory rates and tidal volume had been increased retrospectively, until that ETCO 2 ≤35 mmHg was received. We used ANOVA, Chi-square, and descriptive tests for data analysis. P Tidal volume 10 min after filter insertion was statistically higher in Group 3 (145.0 ± 26.3 ml) versus 129.3 ± 38.9 ml in Group 1 and 118.7 ± 20.8 ml in Group 2 ( P = 0.02). Furthermore, respiratory rate at this time was statistically higher in Group 2 (25.82 ± 0.43) versus Groups 1 and 3 (21.05 ± 0.20 ml and 21.02 ± 0.60 ml, respectively) ( P = 0.001). Minute volume and PETCO 2 level were statistically significant between Group 1 and the other two groups after filter insertion ( P = 0.01 and P = 0.00,1 respectively). With changing the vital capacity and respiratory rate we can control PETCO 2 level ≤35 mmHg during using of birthing filters in infants. We recommend this instrument during anesthesia of infants.

  4. Evaluation of anastomosis between intrahepatic or extrahepatic vessels by intra-arterial digital subtraction angiography using carbon dioxide

    International Nuclear Information System (INIS)

    Miyazono, Nobuaki; Inoue, Hiroki; Ueno, Kazuto; Nishida, Hirotoshi; Kanetsuki, Ichirou; Miyake, Satoshi; Nakajo, Masayuki

    1995-01-01

    Carbon dioxide (CO 2 ) intra-arterial subtraction angiography (IADSA) was performed in 31 patients with various hepatobiliary disease. The injection sites of CO 2 were proper hepatic artery (10/31; group A), segmental hepatic artery (18/31; group B), and peripheral inferior phrenic artery (3/31; group C), respectively. In group A, only the third order branches of the portal venous system were visualized anterogradely in 8 of 10 patients. In group B, the microcatheter was placed coaxially through a 5 French guiding catheter at the main arterial supply of the tumor in 7 patients and at the peripheral segmental branch of the hepatic artery in 11 patients. The portal venous system was visualized retrogradely in all of the patients regardless of the injection site. The injected CO 2 may flow back into the portal vein through the anastmosis known as the peribiliary or periportal plexus. In group C, not only the portal vein but also the pulmonary artery or pericardial vein were visualized by this method. CO 2 -IADSA was useful to image the minute communications between the various vessels, which have been not hitherto visualized by iodinated contrast medium. (author)

  5. Evaluation of anastomosis between intrahepatic or extrahepatic vessels by intra-arterial digital subtraction angiography using carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Miyazono, Nobuaki; Inoue, Hiroki; Ueno, Kazuto; Nishida, Hirotoshi; Kanetsuki, Ichirou; Miyake, Satoshi; Nakajo, Masayuki [Kagoshima Univ. (Japan). Faculty of Medicine

    1995-04-01

    Carbon dioxide (CO{sub 2}) intra-arterial subtraction angiography (IADSA) was performed in 31 patients with various hepatobiliary disease. The injection sites of CO{sub 2} were proper hepatic artery (10/31; group A), segmental hepatic artery (18/31; group B), and peripheral inferior phrenic artery (3/31; group C), respectively. In group A, only the third order branches of the portal venous system were visualized anterogradely in 8 of 10 patients. In group B, the microcatheter was placed coaxially through a 5 French guiding catheter at the main arterial supply of the tumor in 7 patients and at the peripheral segmental branch of the hepatic artery in 11 patients. The portal venous system was visualized retrogradely in all of the patients regardless of the injection site. The injected CO{sub 2} may flow back into the portal vein through the anastmosis known as the peribiliary or periportal plexus. In group C, not only the portal vein but also the pulmonary artery or pericardial vein were visualized by this method. CO{sub 2}-IADSA was useful to image the minute communications between the various vessels, which have been not hitherto visualized by iodinated contrast medium. (author).

  6. Fractional carbon dioxide laser for the treatment of facial atrophic acne scars: prospective clinical trial with short and long-term evaluation.

    Science.gov (United States)

    Elcin, Gonca; Yalici-Armagan, Basak

    2017-12-01

    The aim of this study was to evaluate the efficacy and safety of fractional carbon dioxide laser for the treatment of acne scars. Thirty-one participants, 15 female and 16 male, whose mean age was 34.84 ± 10.94 years, were included in this prospective study. The study took place between 2012 and 2016. Participants were evaluated with the "ECCA Grading Scale" before the first session, 3 months (short-term evaluation) and 3 years after the last session (long-term evaluation). Participants received two or three treatment sessions at 4-week intervals, with a 10,600 nm fractional carbon dioxide laser with pulse energies ranging between 100 and 160 mJ, 120 spot type, 75-100 spot/cm 2 density, and 30 W power. Self-assessments by the participants were done 3 months and 3 years after the last session. The mean ECCA score was 107.90 ± 39.38 before the first session, and 82.17 ± 36.23 at the time of short-term evaluation (p = 0.000). The grade of improvement at the short-term evaluation was as follows: no improvement, mild, moderate, and significant improvement for 7 (22.6%), 11 (35.5%), 9 (29%), and 4 (12.9%) of the participants, respectively. Regarding self-assessments, 80.6 and 61.3% of the participants rated themselves as having at least mild improvement at the short-term and the long-term follow-up periods, respectively. The results of this study suggest that fractional carbon dioxide laser is an efficient treatment option for acne scars. Furthermore, self-assessment results show that more than half of the participants still experience at least mild improvement at the end of 3 years.

  7. Monitoring carbon dioxide in mechanically ventilated patients during hyperbaric treatment

    DEFF Research Database (Denmark)

    Bjerregård, Asger; Jansen, Erik

    2012-01-01

    Measurement of the arterial carbon dioxide (P(a)CO(2)) is an established part of the monitoring of mechanically ventilated patients. Other ways to get information about carbon dioxide in the patient are measurement of end-tidal carbon dioxide (P(ET)CO(2)) and transcutaneous carbon dioxide (PTCCO2......). Carbon dioxide in the blood and cerebral tissue has great influence on vasoactivity and thereby blood volume of the brain. We have found no studies on the correlation between P(ET)CO(2) or P(TC)CO(2), and P(a)CO(2) during hyperbaric oxygen therapy (HBOT)....

  8. Energy efficient solvent regeneration process for carbon dioxide capture

    Science.gov (United States)

    Zhou, Shaojun; Meyer, Howard S.; Li, Shiguang

    2018-02-27

    A process for removing carbon dioxide from a carbon dioxide-loaded solvent uses two stages of flash apparatus. Carbon dioxide is flashed from the solvent at a higher temperature and pressure in the first stage, and a lower temperature and pressure in the second stage, and is fed to a multi-stage compression train for high pressure liquefaction. Because some of the carbon dioxide fed to the compression train is already under pressure, less energy is required to further compress the carbon dioxide to a liquid state, compared to conventional processes.

  9. Materials for carbon dioxide separation

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Qingqing

    2014-10-01

    The CO{sub 2} adsorption capacities at room temperature have been investigated by comparing carbon nanotubes, fullerene, graphenes, graphite and granular activated carbons. It turned out that the amount of the micropore surface area was dominating the CO{sub 2} adsorption ability. Another promising class of materials for CO{sub 2} capture and separation are CaO derived from the eggshells. Two aspects were studied in present work: a new hybrid materials synthesized by doping the CaTiO{sub 3} and the relationship between physisorption and chemisorption properties of CaO-based materials.

  10. Materials for carbon dioxide separation

    International Nuclear Information System (INIS)

    Xu, Qingqing

    2014-01-01

    The CO 2 adsorption capacities at room temperature have been investigated by comparing carbon nanotubes, fullerene, graphenes, graphite and granular activated carbons. It turned out that the amount of the micropore surface area was dominating the CO 2 adsorption ability. Another promising class of materials for CO 2 capture and separation are CaO derived from the eggshells. Two aspects were studied in present work: a new hybrid materials synthesized by doping the CaTiO 3 and the relationship between physisorption and chemisorption properties of CaO-based materials.

  11. Carbon dioxide research conference: carbon dioxide, science and consensus

    International Nuclear Information System (INIS)

    1983-02-01

    The DOE program focuses on three areas each of which requires more research before the many CO 2 -related questions can be answered. These areas include the global carbon cycle, climate effects, and vegetation effects. Additional information is needed to understand the sources and sinks of CO 2 . Research efforts include an attempt to estimate regional and global changes in temperature and precipitation. Increased atmospheric CO 2 may be a potential benefit to vegetation and crops because it is an essential element required for plant growth. Eight separate papers are included

  12. Suppressing bullfrog larvae with carbon dioxide

    Science.gov (United States)

    Gross, Jackson A.; Ray, Andrew; Sepulveda, Adam J.; Watten, Barnaby J.; Densmore, Christine L.; Layhee, Megan J.; Mark Abbey-Lambert,; ,

    2014-01-01

    Current management strategies for the control and suppression of the American Bullfrog (Lithobates catesbeianus = Rana catesbeiana Shaw) and other invasive amphibians have had minimal effect on their abundance and distribution. This study evaluates the effects of carbon dioxide (CO2) on pre- and prometamorphic Bullfrog larvae. Bullfrogs are a model organism for evaluating potential suppression agents because they are a successful invader worldwide. From experimental trials we estimated that the 24-h 50% and 99% lethal concentration (LC50 and LC99) values for Bullfrog larvae were 371 and 549 mg CO2/L, respectively. Overall, larvae that succumbed to experimental conditions had a lower body condition index than those that survived. We also documented sublethal changes in blood chemistry during prolonged exposure to elevated CO2. Specifically, blood pH decreased by more than 0.5 pH units after 9 h of exposure and both blood partial pressure of CO2 (pCO2) and blood glucose increased. These findings suggest that CO2 treatments can be lethal to Bullfrog larvae under controlled laboratory conditions. We believe this work represents the necessary foundation for further consideration of CO2 as a potential suppression agent for one of the most harmful invaders to freshwater ecosystems.

  13. Research Progress in Carbon Dioxide Storage and Enhanced Oil Recovery

    Science.gov (United States)

    Wang, Keliang; Wang, Gang; Lu, Chunjing

    2018-02-01

    With the rapid development of global economy, human beings have become highly dependent upon fossil fuel such as coal and petroleum. Much fossil fuel is consumed in industrial production and human life. As a result, carbon dioxide emissions have been increasing, and the greenhouse effects thereby generated are posing serious threats to environment of the earth. These years, increasing average global temperature, frequent extreme weather events and climatic changes cause material disasters to the world. After scientists’ long-term research, ample evidences have proven that emissions of greenhouse gas like carbon dioxide have brought about tremendous changes to global climate. To really reduce carbon dioxide emissions, governments of different countries and international organizations have invested much money and human resources in performing research related to carbon dioxide emissions. Manual underground carbon dioxide storage and carbon dioxide-enhanced oil recovery are schemes with great potential and prospect for reducing carbon dioxide emissions. Compared with other schemes for reducing carbon dioxide emissions, aforementioned two schemes exhibit high storage capacity and yield considerable economic benefits, so they have become research focuses for reducing carbon dioxide emissions. This paper introduces the research progress in underground carbon dioxide storage and enhanced oil recovery, pointing out the significance and necessity of carbon dioxide-driven enhanced oil recovery.

  14. Carbon dioxide emissions from biochar in soil

    DEFF Research Database (Denmark)

    Bruun, Sander; Clauson-Kaas, Anne Sofie Kjærulff; Bobuľská, L.

    2014-01-01

    The stability of biochar in soil is of importance if it is to be used for carbon sequestration and long-term improvement of soil properties. It is well known that a significant fraction of biochar is highly stable in soil, but carbon dioxide (CO2) is also released immediately after application....... This study investigated the nature of the early release of CO2 and the degree to which stabilizing mechanisms protect biochar from microbial attack. Incubations of 14C-labelled biochar produced at different temperatures were performed in soils with different clay contents and in sterilized and non......-sterilized soils. It emerged that carbonate may be concentrated or form during or after biochar production, resulting in significant carbonate contents. If CO2 released from carbonates in short-term experiments is misinterpreted as mineralization of biochar, the impact of this process may be significantly over...

  15. Full-scale multi-ejector module for a carbon dioxide supermarket refrigeration system: Numerical study of performance evaluation

    International Nuclear Information System (INIS)

    Bodys, Jakub; Palacz, Michal; Haida, Michal; Smolka, Jacek; Nowak, Andrzej J.; Banasiak, Krzysztof; Hafner, Armin

    2017-01-01

    Highlights: • A numerical study of the full-scale multi-ejector module performance was presented. • The module was characterised by stable operation in each considered configuration. • The module showed a high total efficiency for all the operating conditions. - Abstract: The performance of fixed ejectors installed in a multi-ejector module in a carbon dioxide refrigeration system is discussed in this paper. To analyse the module operation, three-dimensional ejector models including the inlet and outlet collecting ducts were considered. The tests were performed for three of four vapour ejectors of different sizes that compose the multi-ejector pack. The testing modes included the serial and parallel operation of the fixed units in operating conditions that are characteristic for the supermarket refrigeration unit working at high ambient temperatures. All numerical simulations were performed using the validated Homogeneous Equilibrium Model implemented on the ejectorPL computational tool for typical transcritical parameters at the motive nozzle port. The detailed analysis was executed separately for the ejectors and the ducts of the module collectors. The results discussion concerned the crucial parameters for such an installation like the pressure and vapour quality distribution. Negligible influence of the motive nozzle collector and a crucial influence of the outlet collector shape was indicated. The global performance analysis showed that the multi-ejector pack provides high and stable performance of all installed ejectors over the entire range of the considered operating conditions for supermarket application. Areas of the possible pressure loss reduction and the uniformity growth in the vapour quality distribution were presented. Finally, according to the multi-ejector pack ducts analysis, the potential areas for module shape optimisation were indicated as well.

  16. Carbon dioxide sequestration by direct mineral carbonation with carbonic acid

    Energy Technology Data Exchange (ETDEWEB)

    O' Connor, William K.; Dahlin, David C.; Nilsen, David N.; Walters, Richard P.; Turner, Paul C.

    2000-01-01

    The Albany Research Center (ARC) of the U.S. Dept. of Energy (DOE) has been conducting a series of mineral carbonation tests at its Albany, Oregon, facility over the past 2 years as part of a Mineral Carbonation Study Program within the DOE. Other participants in this Program include the Los Alamos National Laboratory, Arizona State University, Science Applications International Corporation, and the DOE National Energy Technology Laboratory. The ARC tests have focused on ex-situ mineral carbonation in an aqueous system. The process developed at ARC utilizes a slurry of water mixed with a magnesium silicate mineral, olivine [forsterite end member (Mg2SiO4)], or serpentine [Mg3Si2O5(OH)4]. This slurry is reacted with supercritical carbon dioxide (CO2) to produce magnesite (MgCO3). The CO2 is dissolved in water to form carbonic acid (H2CO3), which dissociates to H+ and HCO3 -. The H+ reacts with the mineral, liberating Mg2+ cations which react with the bicarbonate to form the solid carbonate. The process is designed to simulate the natural serpentinization reaction of ultramafic minerals, and for this reason, these results may also be applicable to in-situ geological sequestration regimes. Results of the baseline tests, conducted on ground products of the natural minerals, have been encouraging. Tests conducted at ambient temperature (22 C) and subcritical CO2 pressures (below 73 atm) resulted in very slow conversion to the carbonate. However, when elevated temperatures and pressures are utilized, coupled with continuous stirring of the slurry and gas dispersion within the water column, significant reaction occurs within much shorter reaction times. Extent of reaction, as measured by the stoichiometric conversion of the silicate mineral (olivine) to the carbonate, is roughly 90% within 24 hours, using distilled water, and a reaction temperature of 185?C and a partial pressure of CO2 (PCO2) of 115 atm. Recent tests using a bicarbonate solution, under identical reaction

  17. Carbon dioxide sequestration by direct mineral carbonation with carbonic acid

    Energy Technology Data Exchange (ETDEWEB)

    O' Connor, W.K.; Dahlin, D.C.; Nilsen, D.N.; Walters, R.P.; Turner, P.C.

    2000-07-01

    The Albany Research Center (ARC) of the US Department of Energy (DOE) has been conducting a series of mineral carbonation tests at its Albany, Oregon, facility over the past 2 years as part of a Mineral Carbonation Study Program within the DOE. The ARC tests have focused on ex-situ mineral carbonation in an aqueous system. The process developed at ARC utilizes a slurry of water mixed with a magnesium silicate mineral, olivine [forsterite and member (mg{sub 2}SiO{sub 4})], or serpentine [Mg{sub 3}Si{sub 2}O{sub 5}(OH){sub 4}]. This slurry is reacted with supercritical carbon dioxide (CO{sub 2}) to produce magnesite (MgCO{sub 3}). The CO{sub 2} is dissolved in water to form carbonic acid (H{sub 2}CO{sub 3}), which dissociates to H{sup +} and HCO{sub 3}{sup {minus}}. The H{sup +} reacts with the mineral, liberating Mg{sup 2+} cations which react with the bicarbonate to form the solid carbonate. The process is designed to simulate the natural serpentinization reaction of ultramafic minerals, and for this reason, these results may also be applicable to in-situ geological sequestration regimes. Results of the baseline tests, conducted on ground products of the natural minerals, have been encouraging. Tests conducted at ambient temperature (22 C) and subcritical CO{sub 2} pressures (below 73 atm) resulted in very slow conversion to the carbonate. However, when elevated temperatures and pressures are utilized, coupled with continuous stirring of the slurry and gas dispersion within the water column, significant reaction occurs within much shorter reaction times. Extent of reaction, as measured by the stoichiometric conversion of the silicate mineral (olivine) to the carbonate, is roughly 90% within 24 hours, using distilled water, and a reaction temperature of 185 C and a partial pressure of CO{sub 2} (P{sub CO{sub 2}}) of 115 atm. Recent tests using a bicarbonate solution, under identical reaction conditions, have achieved roughly 83% conversion of heat treated serpentine

  18. Recycling technology of emitted carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Arakawa, Hironori [National Inst. of Materials and Chemical Research (NIMC), Ibaraki (Japan)

    1993-12-31

    Ways to halt global warming are being discussed worldwide. Global warming is an energy problem which is mainly attributed to the large volumes of carbon dioxide (CO{sub 2}) released into the atmosphere from the rapid increase in energy consumption since the Industrial Revolution. The basic solution to the problem, therefore, is to cut consumption of fossil fuels. To this end, it is important to promote energy conservation by improving the fuel efficiency of machines, as well as shift to energy sources that do not emit carbon dioxide and develop related technologies. If current trends in economic growth continue in the devloping world as well as the developed countries, there can be no doubt that energy consumption will increase. Therefore, alongside energy conservation and the development of alternative energies, the importance of technologies to recover and fix CO{sub 2} will increase in the fight against global warming.

  19. Carbon dioxide may become a resource

    International Nuclear Information System (INIS)

    Haugneland, Petter; Areklett, Ivar

    2002-01-01

    The greenhouse gas CO 2 may become a product that the oil companies would pay for. In an extensive international resource project methods for CO 2 capture, transport and storage are being investigated. CO 2 capture means that carbon dioxide that is formed in the combustion of fossil fuels is separated out from the process, either from the fuel (decarbonization), or from the flue gas, and then stored. The article briefly describes the international joint project CO 2 Capture Project (CCP), in which eight oil companies are participating. If one can find a method for injecting CO 2 into oil reservoirs that leads to increased oil production, then part of the extra cost of removing the carbon dioxide from flue gas may be repaid

  20. Relationship between Sampling Distance and Carbon Dioxide Emission under Oil Palm Plantation

    Directory of Open Access Journals (Sweden)

    Ai Dariah

    2013-05-01

    Full Text Available A carbon dioxide emission on peatland under oil palm plantation was highly varied due to many factors involved. The objectives of the research were to evaluate the effect of sampling distance from center of oil palm tree on Carbon dioxide flux, and to study the factors that cause variability of carbon dioxide flux on peatland under oil palm plantation. The study was conducted on peatland at Arang-Arang Village, Kumpek Ulu Sub-District, Muaro Jambi District, Jambi Province, on six-years old oil palm plantation. The study was conducted in the form of observational exploratory. Emission measurements were performed on 5 selected oil palm trees at points within 100, 150, 200, 250, 300, 350, and 400 cm from the center of trunk. Carbon dioxide flux was measured using (IRGA, Li-COR 820. The results showed that there was significant correlation between the distance of sampling from center of oil palm tree and Carbon dioxide flux. The farther distance from the tree, the more decreased of Carbon dioxide flux . Before applying fertilizer, variability of soil fertility was not significantly correlated with the flux of Carbon dioxide, so the difference of Carbon dioxide flux based on distance sampling can be caused by root distribution factor. After fertilizer application, variability of Carbon dioxide flux under the oil palm tree were not only affected by differences in root distribution but also greatly influenced by fertilization.

  1. Direct carbon dioxide emissions from civil aircraft

    OpenAIRE

    Grote, Matt; Williams, Ian; Preston, John

    2014-01-01

    Global airlines consume over 5 million barrels of oil per day, and the resulting carbon dioxide (CO2) emitted by aircraft engines is of concern. This article provides a contemporary review of the literature associated with the measures available to the civil aviation industry for mitigating CO2 emissions from aircraft. The measures are addressed under two categories – policy and legal-related measures, and technological and operational measures. Results of the review are used to develop sever...

  2. Dependence of carbon dioxide concentration on microalgal carbon dioxide fixation

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Yeoung Sang; Park, Song Moon [Department of Chemical Engineering, School of Environmental Engineering, Pohang University of Science and Technology, Pohang (Korea); Bolesky, Bohumil [Department of Chemical Engineering, McGill University (Canada)

    1999-10-01

    Batch cultivation of chlorella vulgaris was carried out under various CO{sub 2} concentrations in order to understand and describe mathematically the CO{sub 2} inhibition of microalgal CO{sub 2} fixation. The volumetric CO{sub 2} transfer coefficient from mixture gas to culture medium was estimated from the volumetric O{sub 2} transfer coefficient obtained experimentally. Using this transfer coefficient and aquatic equilibrium relationship between dissolved inorganic carbons, the behavior of dissolved CO{sub 2} was calculated during microalgal culture. When air containing 0.035%(v/v) CO{sub 2} was supplied into microalgal culture, the fixation rate was limited by CO{sub 2} transfer rate. However, the limitation was disappeared by supplying mixture gas containing above 2%(v/v) CO{sub 2} and the dissolved CO{sub 2} concentration was maintained at the saturated value. In the range of CO{sub 2} partial pressure in the flue gases from thermal power sations and steel-making plants, the microalgal CO{sub 2} fixation rate was inhibited. The CO{sub 2} fixation rate was successfully formulated by a new empirical equation as a function of dissolved CO{sub 2} concentration, which could be useful for modeling and simulating the performance of photobioreaction with enriched CO{sub 2}. Also, it was found that the CO{sub 2} inhibition of microalgal CO{sub 2} fixation was reversible and that microalgal CO{sub 2} fixation process could be stable against a shock of unusually high CO{sub 2} concentration. 29 refs., 8 figs.

  3. Electrocatalytic process for carbon dioxide conversion

    Science.gov (United States)

    Masel, Richard I.; Salehi-Khojin, Amin; Kutz, Robert

    2017-11-14

    An electrocatalytic process for carbon dioxide conversion includes combining a Catalytically Active Element and a Helper Polymer in the presence of carbon dioxide, allowing a reaction to proceed to produce a reaction product, and applying electrical energy to said reaction to achieve electrochemical conversion of said carbon dioxide reactant to said reaction product. The Catalytically Active Element can be a metal in the form of supported or unsupported particles or flakes with an average size between 0.6 nm and 100 nm. The reaction products comprise at least one of CO, HCO.sup.-, H.sub.2CO, (HCO.sub.2).sup.-, H.sub.2CO.sub.2, CH.sub.3OH, CH.sub.4, C.sub.2H.sub.4, CH.sub.3CH.sub.2OH, CH.sub.3COO.sup.-, CH.sub.3COOH, C.sub.2H.sub.6, (COOH).sub.2, (COO.sup.-).sub.2, and CF.sub.3COOH.

  4. Carbon dioxide in Arctic and subarctic regions

    Energy Technology Data Exchange (ETDEWEB)

    Gosink, T. A.; Kelley, J. J.

    1981-03-01

    A three year research project was presented that would define the role of the Arctic ocean, sea ice, tundra, taiga, high latitude ponds and lakes and polar anthropogenic activity on the carbon dioxide content of the atmosphere. Due to the large physical and geographical differences between the two polar regions, a comparison of CO/sub 2/ source and sink strengths of the two areas was proposed. Research opportunities during the first year, particularly those aboard the Swedish icebreaker, YMER, provided additional confirmatory data about the natural source and sink strengths for carbon dioxide in the Arctic regions. As a result, the hypothesis that these natural sources and sinks are strong enough to significantly affect global atmospheric carbon dioxide levels is considerably strengthened. Based on the available data we calculate that the whole Arctic region is a net annual sink for about 1.1 x 10/sup 15/ g of CO/sub 2/, or the equivalent of about 5% of the annual anthropogenic input into the atmosphere. For the second year of this research effort, research on the seasonal sources and sinks of CO/sub 2/ in the Arctic will be continued. Particular attention will be paid to the seasonal sea ice zones during the freeze and thaw periods, and the tundra-taiga regions, also during the freeze and thaw periods.

  5. Capacitance-Assisted Sustainable Electrochemical Carbon Dioxide Mineralisation.

    Science.gov (United States)

    Lamb, Katie J; Dowsett, Mark R; Chatzipanagis, Konstantinos; Scullion, Zhan Wei; Kröger, Roland; Lee, James D; Aguiar, Pedro M; North, Michael; Parkin, Alison

    2018-01-10

    An electrochemical cell comprising a novel dual-component graphite and Earth-crust abundant metal anode, a hydrogen producing cathode and an aqueous sodium chloride electrolyte was constructed and used for carbon dioxide mineralisation. Under an atmosphere of 5 % carbon dioxide in nitrogen, the cell exhibited both capacitive and oxidative electrochemistry at the anode. The graphite acted as a supercapacitive reagent concentrator, pumping carbon dioxide into aqueous solution as hydrogen carbonate. Simultaneous oxidation of the anodic metal generated cations, which reacted with the hydrogen carbonate to give mineralised carbon dioxide. Whilst conventional electrochemical carbon dioxide reduction requires hydrogen, this cell generates hydrogen at the cathode. Carbon capture can be achieved in a highly sustainable manner using scrap metal within the anode, seawater as the electrolyte, an industrially relevant gas stream and a solar panel as an effective zero-carbon energy source. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  6. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    Energy Technology Data Exchange (ETDEWEB)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; Alejandro Lopez-Ortiz; Douglas P. Harrison; Ya Liang

    2001-07-01

    Sodium based sorbents including sodium carbonate may be used to capture carbon dioxide from flue gas. A relatively concentrated carbon dioxide stream may be recoverable for sequestration when the sorbent is regenerated. Electrobalance tests indicated that sodium carbonate monohydrate was formed in a mixture of helium and water vapor at temperatures below 65 C. Additional compounds may also form, but this could not be confirmed. In the presence of carbon dioxide and water vapor, both the initial reaction rate of sodium carbonate with carbon dioxide and water and the sorbent capacity decreased with increasing temperature, consistent with the results from the previous quarter. Increasing the carbon dioxide concentration at constant temperature and water vapor concentration produced a measurable increase in rate, as did increasing the water vapor concentration at constant carbon dioxide concentration and temperature. Runs conducted with a flatter TGA pan resulted in a higher initial reaction rate, presumably due to improved gas-solid contact, but after a short time, there was no significant difference in the rates measured with the different pans. Analyses of kinetic data suggest that the surface of the sodium carbonate particles may be much hotter than the bulk gas due to the highly exothermic reaction with carbon dioxide and water, and that the rate of heat removal from the particle may control the reaction rate. A material and energy balance was developed for a cyclic carbonation/calcination process which captures about 26 percent of the carbon dioxide present in flue gas available at 250 C.

  7. Carbon Dioxide Separation Using Thermally Optimized Membranes

    Science.gov (United States)

    Young, J. S.; Jorgensen, B. S.; Espinoza, B. F.; Weimer, M. W.; Jarvinen, G. D.; Greenberg, A.; Khare, V.; Orme, C. J.; Wertsching, A. K.; Peterson, E. S.; Hopkins, S. D.; Acquaviva, J.

    2002-05-01

    The purpose of this project is to develop polymeric-metallic membranes for carbon dioxide separations that operate under a broad range of industrially relevant conditions not accessible with present membrane units. The last decade has witnessed a dramatic increase in the use of polymer membranes as an effective, economic and flexible tool for many commercial gas separations including air separation, the recovery of hydrogen from nitrogen, carbon monoxide, and methane mixtures, and the removal of carbon dioxide from natural gas. In each of these applications, high fluxes and excellent selectivities have relied on glassy polymer membranes which separate gases based on both size and solubility differences. To date, however, this technology has focused on optimizing materials for near ambient conditions. The development of polymeric materials that achieve the important combination of high selectivity, high permeability, and mechanical stability at temperatures significantly above 25oC and pressures above 10 bar, respectively, has been largely ignored. Consequently, there is a compelling rationale for the exploration of a new realm of polymer membrane separations. Indeed, the development of high temperature polymeric-metallic composite membranes for carbon dioxide separation at temperatures of 100-450 oC and pressures of 10-150 bar would provide a pivotal contribution with both economic and environmental benefits. Progress to date includes the first ever fabrication of a polymeric-metallic membrane that is selective from room temperature to 370oC. This achievement represents the highest demonstrated operating temperature at which a polymeric based membrane has successfully functioned. Additionally, we have generated the first polybenzamidizole silicate molecular composites. Finally, we have developed a technique that has enabled the first-ever simultaneous measurements of gas permeation and membrane compaction at elevated temperatures. This technique provides a unique

  8. The carbon dioxide thermometer and the cause of global warming

    International Nuclear Information System (INIS)

    Calder, Nigel

    1999-01-01

    Carbon dioxide in the air may be increasing because the world is warming. This possibility, which contradicts the hypothesis of an enhanced greenhouse warming driven by manmade emissions, is here pursued in two ways. First, increments in carbon dioxide are treated as readings of a natural thermometer that tracks global and hemispheric temperature deviations, as gauged by meteorologists' thermometers. Calibration of the carbon dioxide thermometer to conventional temperatures then leads to a history of carbon dioxide since 1856 that diverges from the ice-core record. Secondly, the increments of carbon dioxide can also be accounted for, without reference to temperature, by the combined effects of cosmic rays, El Nino and volcanoes. The most durable effect is due to cosmic rays. A solar wind history, used as a long-term proxy for the cosmic rays, gives a carbon dioxide history similar to that inferred from the global temperature deviations. (author)

  9. Amperometric sensor for carbon dioxide: design, characteristics, and perforance

    International Nuclear Information System (INIS)

    Evans, J.; Pletcher, D.; Warburton, P.R.G.; Gibbs, T.K.

    1989-01-01

    A new sensor for atmospheric carbon dioxide is described. It is an amperometric device based on a porous electrode in a three-electrode cell and the electrolyte is a copper diamine complex in aqueous potassium chloride. The platinum cathode, held at constant potential, is used to detect the formation of Cu 2+ following the change in the pH of the solution when the sensor is exposed to an atmosphere containing carbon dioxide. The sensor described is designed to monitor carbon dioxide concentrations in the range 0-5%, although with some modifications, other ranges would be possible. The response to a change in the carbon dioxide content of the atmosphere is rapid (about 10s) while the monitored current is strongly (but nonlinearly) dependent on carbon dioxide concentration. Unlike other amperometric devices for carbon dioxide, there is no interference from oxygen although other acid gases would lead to an interfering response

  10. Effects of carbon dioxide on Penicillium chrysogenum: an autoradiographic study

    International Nuclear Information System (INIS)

    Edwards, A.G.; Ho, C.S.

    1988-01-01

    Previous research has shown that dissolved carbon dioxide causes significant changes in submerged penicillin fermentations, such as stunted, swollen hyphae, increased branching, lower growth rates, and lower penicillin productivity. Influent carbon dioxide levels of 5 and 10% were shown through the use of autoradiography to cause an increase in chitin synthesis in submerged cultures of Penicillium chrysogenum. At an influent 5% carbon dioxide level, chitin synthesis is ca. 100% greater in the subapical region of P. chrysogenum hyphae than that of the control, in which there was no influent carbon dioxide. Influent carbon dioxide of 10% caused an increase of 200% in chitin synthesis. It is believed that the cell wall must be plasticized before branching can occur and that high amounts of dissolved carbon dioxide cause the cell to lose control of the plasticizing effect, thus the severe morphological changes occur

  11. Underground storage of carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Shoichi [Univ. of Tokyo, Hongo, Bunkyo-ku (Japan)

    1993-12-31

    Desk studies on underground storage of CO{sub 2} were carried out from 1990 to 1991 fiscal years by two organizations under contract with New Energy and Indestrial Technology Development Organization (NEDO). One group put emphasis on application of CO{sub 2} EOR (enhanced oil recovery), and the other covered various aspects of underground storage system. CO{sub 2} EOR is a popular EOR method in U.S. and some oil countries. At present, CO{sub 2} is supplied from natural CO{sub 2} reservoirs. Possible use of CO{sub 2} derived from fixed sources of industries is a main target of the study in order to increase oil recovery and storage CO{sub 2} under ground. The feasibility study of the total system estimates capacity of storage of CO{sub 2} as around 60 Gton CO{sub 2}, if worldwide application are realized. There exist huge volumes of underground aquifers which are not utilized usually because of high salinity. The deep aquifers can contain large amount of CO{sub 2} in form of compressed state, liquefied state or solution to aquifer. A preliminary technical and economical survey on the system suggests favorable results of 320 Gton CO{sub 2} potential. Technical problems are discussed through these studies, and economical aspects are also evaluated.

  12. Nuclear power and carbon dioxide free automobiles

    International Nuclear Information System (INIS)

    Pendergast, D.R.

    1999-01-01

    Nuclear energy has been developed as a major source of electric power in Canada. Electricity from nuclear energy already avoids the emission of about 100 million tonnes of carbon dioxide to the atmosphere in Canada. This is a significant fraction of the 619 million tonnes of Canadian greenhouse gas emissions in 1995. However, the current scope of application of electricity to end use energy needs in Canada limits the contribution nuclear energy can make to carbon dioxide emission reduction. Nuclear energy can also contribute to carbon dioxide emissions reduction through expansion of the use of electricity to less traditional applications. Transportation, in particular contributed 165 million tonnes of carbon dioxide to the Canadian atmosphere in 1995. Canada's fleet of personal vehicles consisted of 16.9 million cars and light trucks. These vehicles were driven on average 21,000 km/year and generated 91 million tonnes of greenhouse gases expressed as a C02 equivalent. Technology to improve the efficiency of cars is under development which is expected to increase the energy efficiency from the 1995 level of about 10 litres/100 km of gasoline to under 3 litres/100km expressed as an equivalent referenced to the energy content of gasoline. The development of this technology, which may ultimately lead to the practical implementation of hydrogen as a portable source of energy for transportation is reviewed. Fuel supply life cycle greenhouse gas releases for several personal vehicle energy supply systems are then estimated. Very substantial reductions of greenhouse gas emissions are possible due to efficiency improvements and changing to less carbon intensive fuels such as natural gas. C02 emissions from on board natural gas fueled versions of hybrid electric cars would be decreased to approximately 25 million t/year from the current 91 million tonnes/year. The ultimate reduction identified is through the use of hydrogen fuel produced via electricity from CANDU power

  13. Adverse effects of the automotive industry on carbon dioxide emissions

    OpenAIRE

    Mpho Bosupeng

    2016-01-01

    This study aims to determine the effects of the automotive industry on carbon dioxide emissions for the period from 1997 to 2010 for diverse economies, as well as the relationships between carbon dioxide discharges and output. The study applies cointegration and causality tests to validate these associations. The results of the Johansen cointegration test depict long-run associations between the quantity of passenger cars and carbon dioxide emissions in France, Sweden, Spain, Hungary and Japa...

  14. On reaction of titanium polonides with carbon dioxide

    International Nuclear Information System (INIS)

    Abakumov, A.S.; Malyshev, M.L.; Reznikova, N.F.

    1986-01-01

    The reaction between titanium polonides and carbon dioxide has been studied by comparing titanium polonide thermal resistance in vacuum and in carbon dioxide. The investigation has shown that titanium mono- and semipolonides fail at temperatures below 350 deg C. Temperature dependence of polonium vapor pressure prepared at failure of the given polonides is determined by the radiotensiometry in carbon dioxide. Enthalpy calculated for this dependence is close to the enthalpy of elementary polonium evaporation in vacuum

  15. Supercritical carbon dioxide: a solvent like no other

    Directory of Open Access Journals (Sweden)

    Jocelyn Peach

    2014-08-01

    Full Text Available Supercritical carbon dioxide (scCO2 could be one aspect of a significant and necessary movement towards green chemistry, being a potential replacement for volatile organic compounds (VOCs. Unfortunately, carbon dioxide has a notoriously poor solubilising power and is famously difficult to handle. This review examines attempts and breakthroughs in enhancing the physicochemical properties of carbon dioxide, focusing primarily on factors that impact solubility of polar and ionic species and attempts to enhance scCO2 viscosity.

  16. Carbon dioxide and climate: an astrophysical perspective

    Energy Technology Data Exchange (ETDEWEB)

    Kandel, R S

    1979-01-01

    In this survey the earth is viewed from the astrophysical perspective, i.e. using global mean values of environmental parameters. The role of carbon dioxide is described in the processes of energy transfer from the earth's surface to space, which determine global climate as measured by the mean surface temperature. Analogies and differences between the problems of the terrestrial atmosphere and those of the solar and stellar atmospheres are examined, both in the computation of model atmospheres and in remote sensing of atmospheric temperature and composition. Subsequently, the temporal astrophysical perspective, with a review of the evolution of CO/sub 2/ abundance and climate on astrophysical or geological time scales, on earth as an Venus (the runaway greenhouse) and on Mars is introduced. Variation of CO/sub 2/ may have been critical to the maintenance of an environment in which life could originate and evolve, and may itself have been affected by life. On human time scales, the recent and continuing increase in atmospheric CO/sub 2/ raises new problems, which are briefly surveyed. It is argued, that the differential greenhouse effect of increased CO/sub 2/ in the earth's atmosphere is essentially identifical to the blanketing effect of spectral lines on the temperature structure of stellar atmospheres. The methods used by astrophysicists in such studies are reviewed and compared with those used to evaluate the differential greenhouse effect of CO/sub 2/ in radiative-convective models of the earth's atmosphere. The latter methods remain relatively crude, but recent results by different authors are in reasonably good agreement; however, the astrophysical perspective, i.e. the use of one-dimensional global mean models, remains a gross simplification of the real complexity of the earth's climate system, which is also true in stellar atmospheres.

  17. Changes in plasma potassium concentration during carbon dioxide pneumoperitoneum

    DEFF Research Database (Denmark)

    Perner, A; Bugge, K; Lyng, K M

    1999-01-01

    Hyperkalaemia with ECG changes had been noted during prolonged carbon dioxide pneumoperitoneum in pigs. We have compared plasma potassium concentrations during surgery in 11 patients allocated randomly to undergo either laparoscopic or open appendectomy and in another 17 patients allocated randomly...... to either carbon dioxide pneumoperitoneum or abdominal wall lifting for laparoscopic colectomy. Despite an increasing metabolic acidosis, prolonged carbon dioxide pneumoperitoneum resulted in only a slight increase in plasma potassium concentrations, which was both statistically and clinically insignificant....... Thus hyperkalaemia is unlikely to develop in patients with normal renal function undergoing carbon dioxide pneumoperitoneum for laparoscopic surgery....

  18. Selective free radical reactions using supercritical carbon dioxide.

    Science.gov (United States)

    Cormier, Philip J; Clarke, Ryan M; McFadden, Ryan M L; Ghandi, Khashayar

    2014-02-12

    We report herein a means to modify the reactivity of alkenes, and particularly to modify their selectivity toward reactions with nonpolar reactants (e.g., nonpolar free radicals) in supercritical carbon dioxide near the critical point. Rate constants for free radical addition of the light hydrogen isotope muonium to ethylene, vinylidene fluoride, and vinylidene chloride in supercritical carbon dioxide are compared over a range of pressures and temperatures. Near carbon dioxide's critical point, the addition to ethylene exhibits critical speeding up, while the halogenated analogues display critical slowing. This suggests that supercritical carbon dioxide as a solvent may be used to tune alkene chemistry in near-critical conditions.

  19. Carbon dioxide absorbent and method of using the same

    Science.gov (United States)

    Perry, Robert James; O'Brien, Michael Joseph

    2014-06-10

    In accordance with one aspect, the present invention provides a composition which contains the amino-siloxane structures I, or III, as described herein. The composition is useful for the capture of carbon dioxide from process streams. In addition, the present invention provides methods of preparing the amino-siloxane composition. Another aspect of the present invention provides methods for reducing the amount of carbon dioxide in a process stream employing the amino-siloxane compositions of the invention, as species which react with carbon dioxide to form an adduct with carbon dioxide.

  20. Carbon dioxide absorbent and method of using the same

    Energy Technology Data Exchange (ETDEWEB)

    Perry, Robert James; O' Brien, Michael Joseph

    2015-12-29

    In accordance with one aspect, the present invention provides a composition which contains the amino-siloxane structures I, or III, as described herein. The composition is useful for the capture of carbon dioxide from process streams. In addition, the present invention provides methods of preparing the amino-siloxane composition. Another aspect of the present invention provides methods for reducing the amount of carbon dioxide in a process stream employing the amino-siloxane compositions of the invention, as species which react with carbon dioxide to form an adduct with carbon dioxide.

  1. Quantitative evaluation of the safety of mucosal incision and submucosal dissection for colon during endoscopic submucosal dissection using carbon dioxide laser

    Science.gov (United States)

    Noguchi, Takuma; Honda, Norihiro; Hazama, Hisanao; Morita, Yoshinori; Awazu, Kunio

    2018-02-01

    Since the increase in the overall mortality rate in patients with colon cancer is remarkably high in recent years, early treatment is required. For this reason, endoscopic submucosal dissection (ESD) has been at the forefront of international attention as a low invasive treatment for early digestive cancer. In current ESD procedure, an electrosurgical knife is used for mucosal incision and subsequent submucosal dissection. However, the perforation has been reported to occur by approximately 5%. Thus, to enhance the tissue selectivity of this modality, we focused on the application of laser for ESD. A carbon dioxide laser was chosen as a surgical knife because the saline or a sodium hyaluronate solution injected into the submucosal layer in current ESD procedure has a high absorption coefficient at the wavelength of the carbon dioxide laser. In this research, ex vivo experiment was performed at the output power of 3-7 W and discuss the optimum irradiation power of laser. As a result of ex vivo experiment using extracted porcine colon tissues, mucosal incision and submucosal dissection were safely and less invasively performed in every output power, without reaching the thermal damage to a muscular layer. This is because a carbon dioxide laser is strongly absorbed by saline injected into submucosa. ESD using a carbon dioxide laser is a safer method for the treatment of early colon cancer. We are planning to measure and compare the optical and thermal properties of porcine colon with those of human colon.

  2. Heat transfer coefficient for boiling carbon dioxide

    DEFF Research Database (Denmark)

    Knudsen, Hans Jørgen Høgaard; Jensen, Per Henrik

    1998-01-01

    Heat transfer coefficient and pressure drop for boiling carbon dioxide (R744) flowing in a horizontal pipe has been measured. The calculated heat transfer coeeficient has been compared with the Chart correlation of Shah. The Chart Correlation predits too low heat transfer coefficient but the ratio...... between the measured and the calculated heat transfer coefficient is nearly constant and equal 1.9. With this factor the correlation predicts the measured data within 14% (RMS). The pressure drop is of the same order as the measuring uncertainty and the pressure drop has not been compared with correlation's....

  3. Carbon Dioxide Mitigation by Microalgal Photosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Mijeong Lee; Gillis, James M.; Hwang, Jiann Yang [Michigan Technological University, Houghton (United States)

    2003-12-15

    Algal growth studies of Chlorella strains were conducted in a batch mode with bench type experiments. Carbon dioxide fixation rates of the following green microalgae were determined: Chlorella sp. H84, Chlorella sp. A2, Chlorella sorokiniana UTEX 1230, Chlorella vulgaris, and Chlorella pyrenoidosa. C. vulgaris, among other strains of microalgae, showed the highest growth rate (1.17 optical density/5 days). Cultivating conditions for C. vulgaris that produced the highest growth rate were at concentrations of 243 μg CO{sub 2}/mL, 10 mM ammonia, and 1 mM phosphate, with an initial pH range of 7-8.

  4. Nuclear energy significantly reduces carbon dioxide emissions

    International Nuclear Information System (INIS)

    Koprda, V.

    2006-01-01

    This article is devoted to nuclear energy, to its acceptability, compatibility and sustainability. Nuclear energy is non-dispensable part of energy sources with vast innovation potential. The safety of nuclear energy, radioactive waste deposition, and prevention of risk from misuse of nuclear material have to be very seriously adjudged and solved. Nuclear energy is one of the ways how to decrease the contamination of atmosphere with carbon dioxide and it solves partially also the problem of global increase of temperature and climate changes. Given are the main factors responsible for the renaissance of nuclear energy. (author)

  5. The carbon dioxide capture and geological storage

    International Nuclear Information System (INIS)

    2006-06-01

    This road-map proposes by the Group Total aims to inform the public on the carbon dioxide capture and geological storage. One possible means of climate change mitigation consists of storing the CO 2 generated by the greenhouse gases emission in order to stabilize atmospheric concentrations. This sheet presents the CO 2 capture from lage fossil-fueled combustion installations, the three capture techniques and the CO 2 transport options, the geological storage of the CO 2 and Total commitments in the domain. (A.L.B.)

  6. INTERACTION OF CARBON DIOXIDE WITH CARBON ADSORBENTS BELOW 400 C

    Energy Technology Data Exchange (ETDEWEB)

    Deitz, V R; Carpenter, F G; Arnold, R G

    1963-06-15

    The adsorption of carbon dioxide on carbon adsorbents (FT carbon, coconut charcoal, acid-washed bone char) and adsorbents containing basic calcium phosphate (hydroxylapatite, bone char, ash of bone char) was studied. Special consideration was given to the pretreatment of the materials. The carbons equilibrated as rapidly as the temperature; the basic calcium phosphates showed a rapid initial adsorption followed by a very slow rate which continued for days. Linear adsorption isotherms were found on FT carbon and the isosteric heats varied slightiy with coverage. The isotherms for the remaining materials had varying curvature and were for the most part in the same sequence as the estimated surface areas. The isosteric heats of carbon dioxide correlated very well with the magnitude of surface hydroxyl groups, an estimate of which was made from the chemical composition. There appeared to be three increasing levels of interaction: (1) pure physical adsorption; (2) an adsorption complex having 'bicarbonate structure'; and (3) an adsorption complex having 'carbonate structure'. (auth)

  7. Combined effect of sulfur dioxide and carbon dioxide gases on mold fungi

    Energy Technology Data Exchange (ETDEWEB)

    Kochurova, A.I.; Karpova, T.N.

    1974-01-01

    Sulfur dioxide at 0.08% killed Penicillium expansum, Stemphylium macrosporium, and Botrytis cinerea within 24 hours. At 0.2%, it killed P. citrinum, Alternaria tenuis, and Fusarium moniliforme. Sulfur dioxide (at 0.04%) and Sulfur dioxide-carbon dioxide mixtures (at 0.02 and 5% respectively) completely suppressed the growth of P. citrinum, P. expansum, P. rubrum, A. tenuis, S. macrosporium, B. cinerea, and F. moniliforme in laboratory experiments. 1 table.

  8. Climatic response to a gradual increase of atmospheric carbon dioxide

    International Nuclear Information System (INIS)

    Stouffer, R.J.; Manabe, S.; Bryan, K.

    1990-01-01

    The transient response of a coupled ocean-atmosphere model to an increase of carbon dioxide has been the subject of several studies. The models used in these studies explicitly incorporate the effect of heat transport by ocean currents and are different from the model used by Hansen et al. Here the authors evaluate the climatic influence of increasing atmospheric carbon dioxide using a coupled model recently developed at the NOAA Geophysical Fluid Dynamics Laboratory. The model response exhibits a marked and unexpected interhemispheric asymmetry. In the circumpolar ocean of the southern hemisphere, a region of deep vertical mixing, the increase of surface air temperature is very slow. In the Northern hemisphere of the model, the rise of surface air temperature is faster and increases with latitude, with the exception of the northern North Atlantic, where it is relatively slow because of the weakening of the thermohaline circulation

  9. Carbon Dioxide Separation with Supported Ionic Liquid Membranes

    Energy Technology Data Exchange (ETDEWEB)

    Luebke, D.R.; Ilconich, J.B.; Myers, C.R.; Pennline, H.W.

    2007-04-01

    Supported liquid membranes are a class of materials that allow the researcher to utilize the wealth of knowledge available on liquid properties as a direct guide in the development of a capture technology. These membranes also have the advantage of liquid phase diffusivities higher than those observed in polymeric membranes which grant proportionally greater permeabilities. The primary shortcoming of the supported liquid membranes demonstrated in past research has been the lack of stability caused by volatilization of the transport liquid. Ionic liquids, which possess high carbon dioxide solubility relative to light gases such as hydrogen, are an excellent candidate for this type of membrane since they have negligible vapor pressure and are not susceptible to evaporation. A study has been conducted evaluating the use of several ionic liquids, including 1-hexyl-3-methyl-imidazolium bis(trifuoromethylsulfonyl)imide, 1-butyl-3-methyl-imidazolium nitrate, and 1-ethyl-3-methyl-imidazolium sulfate in supported ionic liquid membranes for the capture of carbon dioxide from streams containing hydrogen. In a joint project, researchers at the University of Notre Dame lent expertise in ionic liquid synthesis and characterization, and researchers at the National Energy Technology Laboratory incorporated candidate ionic liquids into supports and evaluated the resulting materials for membrane performance. Initial results have been very promising with carbon dioxide permeabilities as high as 950 barrers and significant improvements in carbon dioxide/hydrogen selectivity over conventional polymers at 37C and at elevated temperatures. Results include a comparison of the performance of several ionic liquids and a number of supports as well as a discussion of innovative fabrication techniques currently under development.

  10. Carbon dioxide laser for de-epithelialization of periodontal flaps.

    Science.gov (United States)

    Centty, I G; Blank, L W; Levy, B A; Romberg, E; Barnes, D M

    1997-08-01

    Regeneration of mineralized and soft connective tissue components of the attachment apparatus is the main goal in the treatment of periodontal diseases. Often, apical migration of epithelium (long junctional epithelium) effectively prevents the formation of bone and connective tissue attachment after periodontal surgery. The purpose of the present study was to compare conventional periodontal surgery combined with carbon dioxide laser and conventional periodontal surgery alone with respect to epithelial elimination and degree of necrosis of mucoperiosteal flaps. After signing a consent form, five patients with at least two comparable bilateral periodontal defects needing pocket elimination surgery participated in this study. The investigators randomly divided each side into test and control sites. Each patient received oral hygiene instruction and initial therapy prior to surgery. At surgery, the test site received a sulcular incision and carbon dioxide laser de-epithelialization of the outer and inner aspects of the flap. The control group received reverse bevel incision only. The surgeon performed open flap debridement on all teeth. At the time of surgery, the surgeon did a biopsy of each site and submitted specimens for histologic evaluation. A matched pairs t-test was used to analyze the data. The results show significant differences between the carbon dioxide laser and reverse bevel incision with respect to sulcular (P test sites, with a predominance of plasma cells. Lining the sulcular and gingival (external) lased areas, investigators found coagulation necrosis covered by fibrin and coagulated blood. The laser appears to effectively remove epithelium at the time of surgery; however, future long-term, well-controlled quantitative histologic studies are needed to evaluate the effect of repeated carbon dioxide laser de-epithelialization of the gingival (external) surface of mucoperiosteal flaps at intervals during the healing period.

  11. An Optimal Centralized Carbon Dioxide Repository for Florida, USA

    Directory of Open Access Journals (Sweden)

    Brandon Poiencot

    2011-03-01

    Full Text Available For over a decade, the United States Department of Energy, and engineers, geologists, and scientists from all over the world have investigated the potential for reducing atmospheric carbon emissions through carbon sequestration. Numerous reports exist analyzing the potential for sequestering carbon dioxide at various sites around the globe, but none have identified the potential for a statewide system in Florida, USA. In 2005, 83% of Florida’s electrical energy was produced by natural gas, coal, or oil (e.g., fossil fuels, from power plants spread across the state. In addition, only limited research has been completed on evaluating optimal pipeline transportation networks to centralized carbon dioxide repositories. This paper describes the feasibility and preliminary locations for an optimal centralized Florida-wide carbon sequestration repository. Linear programming optimization modeling is used to plan and route an idealized pipeline network to existing Florida power plants. Further analysis of the subsurface geology in these general locations will provide insight into the suitability of the subsurface conditions and the available capacity for carbon sequestration at selected possible repository sites. The identification of the most favorable site(s is also presented.

  12. Use of supercritical carbon dioxide extraction

    Energy Technology Data Exchange (ETDEWEB)

    Taniguchi, Masayuki (Niigata Univ., Faculty of Engineering, Niigata, (Japan))

    1989-09-25

    Supercritical fluid extraction is a novel diffusion and separation technique which exploits simultaneously the increase of vapor pressure and the difference of chemical affinities of fluids near the critical point. A solvent which is used as the supercritical fluid has the following features: the critical point exists in the position of relatively ease of handling, the solvent is applicable to the extraction of a physiological active substance of thermal instability. Carbon dioxide as the solvent is non-flammable, non-corrosive, non-toxic, cheap, and readily available of high purity. The results of studies on the use of supercritical carbon dioxide (SC-CO{sub 2}) as a solvent for natural products in the fermentation and food industries, were collected. SC-CO{sub 2} extraction are used in many fields, examples for the application are as follows: removal of organic solvents from antibiotics; extraction of vegetable oils contained in wheat germ oil, high quality mustard seeds, rice bran and so on; brewing of sake using rice and rice-koji; use as a non-aqueous medium for the synthesis of precursors of the Aspartame; and use in sterilization. 66 refs., 17 figs., 21 tabs.

  13. Methanation of hydrogen and carbon dioxide

    International Nuclear Information System (INIS)

    Burkhardt, Marko; Busch, Günter

    2013-01-01

    Highlights: • The biologic methanation of exclusively gases like hydrogen and carbon dioxide is feasible. • Electrical energy can be stored in the established gas grid by conversion to methane. • The quality of produced biogas is very high (c CH4 = 98 vol%). • The conversion rate is depending on H 2 -flow rate. - Abstract: A new method for the methanation of hydrogen and carbon dioxide is presented. In a novel anaerobic trickle-bed reactor, biochemical catalyzed methanation at mesophilic temperatures and ambient pressure can be realized. The conversion of gaseous substrates by immobilized hydrogenotrophic methanogens is a unique feature of this reactor type. The already patented reactor produces biogas which has a very high quality (c CH4 = 97.9 vol%). Therefore, the storage of biogas in the existing natural gas grid is possible without extensive purification. The specific methane production was measured with P = 1.17 Nm CH4 3 /(m R 3 d). It is conceivable to realize the process at sites that generate solar or wind energy and sites subject to the conditions for hydrogen electrolysis (or other methods of hydrogen production). The combination with conventional biogas plants under hydrogen addition to methane enrichment is possible as well. The process enables the coupling of various renewable energy sources

  14. Studies on carbon dioxide power plant, (3)

    International Nuclear Information System (INIS)

    Akagawa, Koji; Fujii, Terushige; Sakaguchi, Tadashi; Kawabata, Yasusuke; Kuroda, Toshihiro.

    1980-01-01

    A power generating plant using carbon dioxide instead of water has been studied by the authors, as high efficiency can be obtained in high temperature range (higher than 650 deg C) and turbines become compact as compared with the Rankine steam cycle. In this paper, the theoretical analysis of the dynamic characteristics of this small power generating plant of supercritical pressure and the comparison with the experimental results are reported. In the theoretical analysis, the linear approximation method using small variation method was adopted for solution. Every component was modeled as the concentrated constant system, and the transfer function for each component was determined, then simulation was carried out for the total system synthesizing these components. The approximation of physical values, and the analysis of a plunger pump, a regenerator, a heater, a vapor valve, a turbine and a blower, piping, and pressure drop are described. The response to the stepwise changes of heating, flow rate, opening of a vapor valve and a load control valve for a blower was investigated. The theoretical anaysis and the experimental results were in good agreement, and this analysis is applicable to the carbon dioxide plant of practical scale. (Kako, I.)

  15. Adaptation to carbon dioxide tax in shipping

    International Nuclear Information System (INIS)

    Olsen, Kristian

    2000-01-01

    This note discusses the consequences for the sea transport sector between Norway and continental Europe of levying a carbon dioxide tax on international bunker. The influence of such a tax on the operational costs of various types of ship and various transport routes is calculated. The profit obtainable from the following ways of adapting to an increased tax level is assessed: (1) Reducing the speed, (2) Rebuilding the engine to decrease fuel consumption, (3) Changing the design speed for new ships. It is found that a carbon dioxide tax of NOK 200 per tonne of CO 2 will increase the transport costs by 3 - 15 percent. In the long run much of this may be transferred to the freight rates since so much of the sea transport are in segments in which the demand for the service is not sensitive to the prices. Even if the freight rates are not changed, a tax this size will not make it necessary to reduce the speed of the existing fleet. The income lost by taking fewer trips will exceed the costs saved in reducing the speed. However, the optimum design speed for new ships may be somewhat reduced (0.5 knots). Rebuilding engines to reduce the fuel consumption would pay off were it not for the fact that the remaining life of the present fleet is probably too short for this to be interesting

  16. Carbon dioxide utilization in a microalga-based biorefinery: Efficiency of carbon removal and economic performance under carbon taxation.

    Science.gov (United States)

    Wiesberg, Igor Lapenda; Brigagão, George Victor; de Medeiros, José Luiz; de Queiroz Fernandes Araújo, Ofélia

    2017-12-01

    Coal-fired power plants are major stationary sources of carbon dioxide and environmental constraints demand technologies for abatement. Although Carbon Capture and Storage is the most mature route, it poses severe economic penalty to power generation. Alternatively, this penalty is potentially reduced by Carbon Capture and Utilization, which converts carbon dioxide to valuable products, monetizing it. This work evaluates a route consisting of carbon dioxide bio-capture by Chlorella pyrenoidosa and use of the resulting biomass as feedstock to a microalgae-based biorefinery; Carbon Capture and Storage route is evaluated as a reference technology. The integrated arrangement comprises: (a) carbon dioxide biocapture in a photobioreactor, (b) oil extraction from part of the produced biomass, (b) gasification of remaining biomass to obtain bio-syngas, and (c) conversion of bio-syngas to methanol. Calculation of capital and operational expenditures are estimated based on mass and energy balances obtained by process simulation for both routes (Carbon Capture and Storage and the biorefinery). Capital expenditure for the biorefinery is higher by a factor of 6.7, while operational expenditure is lower by a factor of 0.45 and revenues occur only for this route, with a ratio revenue/operational expenditure of 1.6. The photobioreactor is responsible for one fifth of the biorefinery capital expenditure, with footprint of about 1000 ha, posing the most significant barrier for technical and economic feasibility of the proposed biorefinery. The Biorefinery and Carbon Capture and Storage routes show carbon dioxide capture efficiency of 73% and 48%, respectively, with capture cost of 139$/t and 304$/t. Additionally, the biorefinery has superior performance in all evaluated metrics of environmental impacts. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. The effect of cutting on carbon dioxide absorption and carbohydrate ...

    African Journals Online (AJOL)

    grass) and Osteospermun sinuatum (Karoo-bush) plants during the flag leaf and flower bud stages respectively resulted in a sharp decline in net carbon dioxide absorption. As new photosynthetic material was produced the total carbon ...

  18. Robust optical carbon dioxide isotope analyzer, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Isotopic analysis of carbon dioxide is an important tool for characterization of the exchange and transformation of carbon between the biosphere and the atmosphere....

  19. Hydrodynamic Controls on Carbon Dioxide Efflux from Inland Waters

    Science.gov (United States)

    Long, H. E.; Waldron, S.; Hoey, T.; Newton, J.; Quemin, S.

    2013-12-01

    Intensive research has been undertaken on carbon dioxide efflux from lakes, estuaries and oceans, but much less attention has been given to rivers and streams, especially lower order streams. River systems are often over-saturated with carbon dioxide and so tend to act as sources of carbon dioxide to the atmosphere. It has been thought that rivers act as pipes carrying this terrestrial carbon to the oceans. However, recent studies have shown that a significant amount of the carbon is reprocessed within the system in a series of transformations and losses. Fluvial evasion of carbon dioxide is now recognised to be a significant component of carbon cycles, however the factors controlling carbon dioxide efflux and its magnitude remain poorly understood and quantified. This research aims to quantify, and better understand the controls on, freshwater carbon dioxide evasion. Data are presented here from field measurements that commenced in Sept 2013 in two contrasting Scottish rivers: the River Kelvin which has a large (335 km.sq) part-urban catchment with predominantly non-peat soils and Drumtee Water, a small (9.6 km.sq) rural catchment of peat soils and agricultural land. Using a floating chamber with the headspace connected to an infrared gas analyser to measure changes in carbon dioxide concentration, efflux rates from 0.22 - 47.4 μmol CO2/m.sq/sec were measured, these close to the middle of the range of previously reported values. At one site on the River Kelvin in May 2013 an influx of -0.61 - -3.53 μmol CO2/m.sq/sec was recorded. Whereas previous research finds carbon dioxide efflux to increase with decreasing river size and a more organic-rich soil catchment, here the controls on carbon dioxide evasion are similar across the contrasting catchments. Carbon dioxide evasion shows seasonality, with maximum fluxes in the summer months being up to twice as high as the winter maxima. Linear regression demonstrates that evasion increases with increased flow velocity

  20. Collision and radiative processes in emission of atmospheric carbon dioxide

    Science.gov (United States)

    Smirnov, B. M.

    2018-05-01

    The peculiarities of the spectroscopic properties of CO2 molecules in air due to vibration-rotation radiative transitions are analyzed. The absorption coefficient due to atmospheric carbon dioxide and other atmospheric components is constructed within the framework of the standard atmosphere model, on the basis of classical molecular spectroscopy and the regular model for the spectroscopy absorption band. The radiative flux from the atmosphere toward the Earth is represented as that of a blackbody, and the radiative temperature for emission at a given frequency is determined with accounting for the local thermodynamic equilibrium, a small gradient of the tropospheric temperature and a high optical thickness of the troposphere for infrared radiation. The absorption band model with an absorption coefficient averaged over the frequency and line-by-line model are used for evaluating the radiative flux from the atmosphere to the Earth which values are nearby for these models and are equal W m‑2 for the contemporary concentration of atmospheric CO2 molecules and W m‑2 at its doubled value. The absorption band model is not suitable to calculate the radiative flux change at doubling of carbon dioxide concentration because averaging over oscillations decreases the range where the atmospheric optical thickness is of the order of one, and just this range determines this change. The line-by-line method gives the change of the global temperature K as a result of doubling the carbon dioxide concentration. The contribution to the global temperature change due to anthropogenic injection of carbon dioxide in the atmosphere, i.e. resulted from combustion of fossil fuels, is approximately 0.02 K now.

  1. Carbon monoxide and carbon dioxide interaction with tantalum

    International Nuclear Information System (INIS)

    Belov, V.D.; Ustinov, Yu.K.; Komar, A.P.

    1978-01-01

    The adsorption of carbon monoxide and carbon dioxide on tantalum and the dissolution of these gases in the adsorbent at T >= 300 K have been studied. The flash-filament method (FFM) in a monopole mass-spectrometer and a field emission microscopy was used in the same apparatus. Carbon monoxide and carbon dioxide dissociate on the tantalum surface, carbon monoxide being desorbed in both cases during the flash. The desorption curves of CO reveal three different binding states: two of them (α and β' 1 ) for the adsorbed particles whereas the high temperature desorption state relates to the adsorbate dissolved in the metal. For the β' 1 state of CO the activation energy, the pre-exponential factor and the kinetic order in the kinetic equation of desorption have been estimated. They turned out to be E = 110 kcal/mol, C = 3 X 10 12 sec -1 , and γ = 1. The activation energy of diffusion for CO in tantalum and the energy of outgassing for the metal were found to be 9.4 and 49 kcal/mole, respectively. (Auth.)

  2. Carbon monoxide and carbon dioxide interaction with tantalum

    Energy Technology Data Exchange (ETDEWEB)

    Belov, V D; USTINOV, YU K; KOMAR, A P [AN SSSR, LENINGRAD. FIZIKO-TEKHNICHESKIJ INST.

    1978-03-01

    The adsorption of carbon monoxide and carbon dioxide on tantalum and the dissolution of these gases in the adsorbent at T >= 300 K have been studied. The flash-filament method (FFM) in a monopole mass-spectrometer and a field emission microscopy was used in the same apparatus. Carbon monoxide and carbon dioxide dissociate on the tantalum surface, carbon monoxide being desorbed in both cases during the flash. The desorption curves of CO reveal three different binding states: two of them (..cap alpha.. and ..beta..'/sub 1/) for the adsorbed particles whereas the high temperature desorption state relates to the adsorbate dissolved in the metal. For the ..beta..'/sub 1/ state of CO the activation energy, the pre-exponential factor and the kinetic order in the kinetic equation of desorption have been estimated. They turned out to be E = 110 kcal/mol, C = 3 X 10/sup 12/ sec/sup -1/, and ..gamma.. = 1. The activation energy of diffusion for CO in tantalum and the energy of outgassing for the metal were found to be 9.4 and 49 kcal/mole, respectively.

  3. Flexible substrates as basis for photocatalytic reduction of carbon dioxide

    DEFF Research Database (Denmark)

    Jensen, Jacob; Mikkelsen, Mette; Krebs, Frederik C

    2011-01-01

    A photocatalytic system for converting carbon dioxide into carbon monoxide was designed and constructed. The system relies on thin films of the photocatalyst prepared at low temperature using spray coating. We formulated inks based on the well-known photocatalyst titanium dioxide and characterized...

  4. Carbon Dioxide and Global Warming: A Failed Experiment

    Science.gov (United States)

    Ribeiro, Carla

    2014-01-01

    Global warming is a current environmental issue that has been linked to an increase in anthropogenic carbon dioxide in the atmosphere. To raise awareness of the problem, various simple experiments have been proposed to demonstrate the effect of carbon dioxide on the planet's temperature. This article describes a similar experiment, which…

  5. Effect of high pressurized carbon dioxide on Escherichia coli ...

    African Journals Online (AJOL)

    Carbon dioxide at high pressure can retard microbial growth and sometimes kill microorganisms depending on values of applied pressure, temperature and exposure time. In this study the effect of high pressurised carbon dioxide (HPCD) on Escherichia coli was investigated. Culture of E. coli was subjected to high ...

  6. Model studies of limitation of carbon dioxide emissions reduction

    International Nuclear Information System (INIS)

    1992-01-01

    The report consists of two papers concerning mitigation of CO 2 emissions in Sweden, ''Limitation of carbon dioxide emissions. Socio-economic effects and the importance of international coordination'', and ''Model calculations for Sweden's energy system with carbon dioxide limitations''. Separate abstracts were prepared for both of the papers

  7. Balance and forecasts of french carbon dioxide emissions

    International Nuclear Information System (INIS)

    1992-11-01

    This paper strikes the balance of carbon dioxide emissions in France between 1986 and 1991 and gives forecasts till 2010. Since 1986, France has reduced its efforts for energy conservation and air pollution by carbon dioxide begins to growth again in connection with consumption growth in transport area, development of computer and simulation needs

  8. Indoor air pollution produced by man (carbon dioxide, odors)

    Energy Technology Data Exchange (ETDEWEB)

    Wanner, H U

    1982-01-01

    Man contributes to indoor air pollution by the release of heat, humidity, carbon dioxide, particles, micro-organisms and body odours. The rise in temperature and the concentrations of the different pollutants depend on the number of persons in a room, the utilization of the room and the activities of the persons. Current parameters for the evaluation of man-made pollution in indoor air are carbon monoxide and odours. Experiments have been carried out in a test chamber under controlled conditions in order to determine the relations between carbon monoxide and odours, since these are two current parameters for the evaluation of man-made pollution in indoor air. In these experiments the variables were the number of persons in the room, the activity of the persons and the ventilation rate. For the measurement of odours a special method has been developed in which the undiluted air is tested by a test panel and compared with air containing two different pyridine concentrations. A significant relationship has been observed between the odour intensity and the carbon dioxide content of the air, and the correlation did not depend on the number of persons and the ventilation rate. At ventilation rates of 12 to 15 m3 per person and hour the carbon dioxide concentration was below 0.15% and the odour intensity was characterized as being only little annoying. Higher ventilation rates are necessary during physical activity and in rooms with tobacco smoke. The minimum ventilation rates as deduced from the laboratory experiments are compared to known standards.

  9. Modelling interactions of carbon dioxide, forests, and climate

    International Nuclear Information System (INIS)

    Luxmoore, R.J.; Baldocchi, D.D.

    1994-01-01

    Atmospheric carbon dioxide is rising and forests and climate is changing exclamation point This combination of fact and premise may be evaluated at a range of temporal and spatial scales with the aid of computer simulators describing the interrelationships between forest vegetation, litter and soil characteristics, and appropriate meteorological variables. Some insights on the effects of climate on the transfers of carbon and the converse effect of carbon transfer on climate are discussed as a basis for assessing the significance of feedbacks between vegetation and climate under conditions of rising atmospheric carbon dioxide. Three main classes of forest models are reviewed. These are physiologically-based models, forest succession simulators based on the JABOWA model, and ecosystem-carbon budget models that use compartment transfer rates with empirically estimated coefficients. Some regression modeling approaches are also outlined. Energy budget models applied to forests and grasslands are also reviewed. This review presents examples of forest models; a comprehensive discussion of all available models is not undertaken

  10. Adverse effects of the automotive industry on carbon dioxide emissions

    Directory of Open Access Journals (Sweden)

    Mpho Bosupeng

    2016-05-01

    Full Text Available This study aims to determine the effects of the automotive industry on carbon dioxide emissions for the period from 1997 to 2010 for diverse economies, as well as the relationships between carbon dioxide discharges and output. The study applies cointegration and causality tests to validate these associations. The results of the Johansen cointegration test depict long-run associations between the quantity of passenger cars and carbon dioxide emissions in France, Sweden, Spain, Hungary and Japan. In addition, significant relations were observed between output and carbon dioxide discharges in Spain, Canada, India and Japan. Changes in output had substantial impact on emissions in Germany, Canada and India. The results also show that the number of passenger cars influences the magnitude of emissions in multiple economies. In conclusion, the automotive industry has to be considered in policies that aim to reduce carbon dioxide emissions.

  11. Carbon dioxide from fossil fuels: adapting to uncertainty

    Energy Technology Data Exchange (ETDEWEB)

    Chen, K; Winter, R C; Bergman, M K

    1980-12-01

    If present scientific information is reasonable, the world is likely to experience noticeable global warming by the beginning of the next century if high annual growth rates of fossil-fuel energy use continue. Only with optimistic assumptions and low growth rates will carbon-dioxide-induced temperature increases be held below 2/sup 0/C or so over the next century. Conservation, flexible energy choices, and control options could lessen the potential effects of carbon dioxide. Though perhaps impractical from the standpoint of costs and efficiency losses, large coastal centralized facilities would be the most amenable to carbon dioxide control and disposal. Yet no country can control carbon dioxide levels unilaterally. The USA, however, which currently contributes over a quarter of all fossil-fuel carbon dioxide emissions and possesses a quarter of the world's coal resources, could provide a much needed role in leadership, research and education. 70 references.

  12. Carbon dioxide stripping in aquaculture. part 1: terminology and reporting

    Science.gov (United States)

    Colt, John; Watten, Barnaby; Pfeiffer, Tim

    2012-01-01

    The removal of carbon dioxide gas in aquacultural systems is much more complex than for oxygen or nitrogen gas because of liquid reactions of carbon dioxide and their kinetics. Almost all published carbon dioxide removal information for aquaculture is based on the apparent removal value after the CO2(aq) + HOH ⇔ H2CO3 reaction has reached equilibrium. The true carbon dioxide removal is larger than the apparent value, especially for high alkalinities and seawater. For low alkalinity freshwaters (<2000 μeq/kg), the difference between the true and apparent removal is small and can be ignored for many applications. Analytical and reporting standards are recommended to improve our understanding of carbon dioxide removal.

  13. Carbon dioxide absorbent and method of using the same

    Science.gov (United States)

    Perry, Robert James [Niskayuna, NY; Lewis, Larry Neil [Scotia, NY; O'Brien, Michael Joseph [Clifton Park, NY; Soloveichik, Grigorii Lev [Latham, NY; Kniajanski, Sergei [Clifton Park, NY; Lam, Tunchiao Hubert [Clifton Park, NY; Lee, Julia Lam [Niskayuna, NY; Rubinsztajn, Malgorzata Iwona [Ballston Spa, NY

    2011-10-04

    In accordance with one aspect, the present invention provides an amino-siloxane composition comprising at least one of structures I, II, III, IV or V said compositions being useful for the capture of carbon dioxide from gas streams such as power plant flue gases. In addition, the present invention provides methods of preparing the amino-siloxane compositions are provided. Also provided are methods for reducing the amount of carbon dioxide in a process stream employing the amino-siloxane compositions of the invention as species which react with carbon dioxide to form an adduct with carbon dioxide. The reaction of the amino-siloxane compositions provided by the present invention with carbon dioxide is reversible and thus, the method provides for multicycle use of said compositions.

  14. Carbon Dioxide Detection and Indoor Air Quality Control.

    Science.gov (United States)

    Bonino, Steve

    2016-04-01

    When building ventilation is reduced, energy is saved because it is not necessary to heat or cool as much outside air. Reduced ventilation can result in higher levels of carbon dioxide, which may cause building occupants to experience symptoms. Heating or cooling for ventilation air can be enhanced by a DCV system, which can save energy while providing a comfortable environment. Carbon dioxide concentrations within a building are often used to indicate whether adequate fresh air is being supplied to the building. These DCV systems use carbon dioxide sensors in each space or in the return air and adjust the ventilation based on carbon dioxide concentration; the higher the concentration, the more people occupy the space relative to the ventilation rate. With a carbon dioxide sensor DCV system, the fresh air ventilation rate varies based on the number ofpeople in the space, saving energy while maintaining a safe and comfortable environment.

  15. Difficult colonoscopy: air, carbon dioxide, or water insufflation?

    Science.gov (United States)

    Chaubal, Alisha; Pandey, Vikas; Patel, Ruchir; Poddar, Prateik; Phadke, Aniruddha; Ingle, Meghraj; Sawant, Prabha

    2018-04-01

    This study aimed to compare tolerance to air, carbon dioxide, or water insufflation in patients with anticipated difficult colonoscopy (young, thin, obese individuals, and patients with prior abdominal surgery or irradiation). Patients with body mass index (BMI) less than 18 kg/m 2 or more than 30 kg/m 2 , or who had undergone previous abdominal or pelvic surgeries were randomized to air, carbon dioxide, or water insufflation during colonoscopy. The primary endpoint was cecal intubation with mild pain (less than 5 on visual analogue scale [VAS]), without use of sedation. The primary end point was achieved in 32.7%, 43.8%, and 84.9% of cases with air, carbon dioxide and water insufflation ( P carbon dioxide, and water insufflation ( P carbon dioxide for pain tolerance. This was seen in the subgroups with BMI 30 kg/m 2 .

  16. New technology for carbon dioxide at high pressure

    International Nuclear Information System (INIS)

    Hassina, Bazaze; Raouf, Zehioua; Menial, A. H.

    2006-01-01

    Carbon dioxide has long been the nemesis of environmentalists because of its role in global warming, but under just the right conditions-namely, high pressure and high temperature its one of nature's best and most environmentally benign solvents. Decaf-coffee lovers, for instance, benefit from its ability to remove caffeine from coffee beans.During the last few years, carbon dioxide has also made inroads in the dry-cleaning industry, providing a safe cleaning alternative to the chemical perchloroethylene. But it's on the high-tech front that carbon dioxide may make its biggest impact. T here are huge opportunities. Scientists have known for more than a century that at 75 times atmospheric pressure and 31 degree centigrade, carbon dioxide goes into and odd state that chemists called s upercritical . What's interesting to industry is that supercritical carbon dioxide may be an enabling technology for going to smaller dimensions.(Author)

  17. Evaluation of ultramafic deposits in the Eastern United States and Puerto Rico as sources of magnesium for carbon dioxide sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Fraser Goff; George Guthrie; Bruce Lipin; Melissa Fite; Steve Chipera; Dale Counce; Emily Kluk; Hans Ziock

    2000-04-01

    In this report, the authors evaluate the resource potential of extractable magnesium from ultramafic bodies located in Vermont, the Pennsylvania-Maryland-District-of-Columbia (PA-MD-DC) region, western North Carolina, and southwestern Puerto Rico. The first three regions occur in the Appalachian Mountains and contain the most attractive deposits in the eastern United States. They were formed during prograde metamorphism of serpentinized peridotite fragments originating from an ophiolite protolith. The ultramafic rocks consist of variably serpentinized dunite, harzburgite, and minor iherzolite generally containing antigorite and/or lizardite as the major serpentine minor phases. Chrysotile contents vary from minor to major, depending on occurrence. Most bodies contain an outer sheath of chlorite-talc-tremolite rock. Larger deposits in Vermont and most deposits in North Carolina contain a core of dunite. Magnesite and other carbonates are common accessories. In these deposits, MgO ranges from 36 to 48 wt % with relatively pure dunite having the highest MgO and lowest H{sub 2}O contents. Ultramafic deposits in southwestern Puerto Rico consist of serpentinized dunite and harzburgite thought to be emplaced as large diapirs or as fragments in tectonic melanges. They consist of nearly pure, low-grade serpentinite in which lizardite and chrysotile are the primary serpentine minerals. Chlorite is ubiquitous in trace amounts. Magnesite is a common accessory. Contents of MgO and H{sub 2}O are rather uniform at roughly 36 and 13 wt %. Dissolution experiments show that all serpentinites and dunite-rich rocks are soluble in 1:1 mixtures of 35% HCl and water by volume. The experiments suggest that low-grade serpentinites from Puerto Rico are slightly more reactive than the higher grade, antigorite-bearing serpentinites of the Appalachian Mountains. The experiments also show that the low-grade serpentinites and relatively pure dunites contain the least amounts of undesirable

  18. Photobiological hydrogen production and carbon dioxide sequestration

    Science.gov (United States)

    Berberoglu, Halil

    Photobiological hydrogen production is an alternative to thermochemical and electrolytic technologies with the advantage of carbon dioxide sequestration. However, it suffers from low solar to hydrogen energy conversion efficiency due to limited light transfer, mass transfer, and nutrient medium composition. The present study aims at addressing these limitations and can be divided in three parts: (1) experimental measurements of the radiation characteristics of hydrogen producing and carbon dioxide consuming microorganisms, (2) solar radiation transfer modeling and simulation in photobioreactors, and (3) parametric experiments of photobiological hydrogen production and carbon dioxide sequestration. First, solar radiation transfer in photobioreactors containing microorganisms and bubbles was modeled using the radiative transport equation (RTE) and solved using the modified method of characteristics. The study concluded that Beer-Lambert's law gives inaccurate results and anisotropic scattering must be accounted for to predict the local irradiance inside a photobioreactor. The need for accurate measurement of the complete set of radiation characteristics of microorganisms was established. Then, experimental setup and analysis methods for measuring the complete set of radiation characteristics of microorganisms have been developed and successfully validated experimentally. A database of the radiation characteristics of representative microorganisms have been created including the cyanobacteria Anabaena variabilis, the purple non-sulfur bacteria Rhodobacter sphaeroides and the green algae Chlamydomonas reinhardtii along with its three genetically engineered strains. This enabled, for the first time, quantitative assessment of the effect of genetic engineering on the radiation characteristics of microorganisms. In addition, a parametric experimental study has been performed to model the growth, CO2 consumption, and H 2 production of Anabaena variabilis as functions of

  19. Carbon dioxide emission from bamboo culms.

    Science.gov (United States)

    Zachariah, E J; Sabulal, B; Nair, D N K; Johnson, A J; Kumar, C S P

    2016-05-01

    Bamboos are one of the fastest growing plants on Earth, and are widely considered to have high ability to capture and sequester atmospheric carbon, and consequently to mitigate climate change. We tested this hypothesis by measuring carbon dioxide (CO2 ) emissions from bamboo culms and comparing them with their biomass sequestration potential. We analysed diurnal effluxes from Bambusa vulgaris culm surface and gas mixtures inside hollow sections of various bamboos using gas chromatography. Corresponding variations in gas pressure inside the bamboo section and culm surface temperature were measured. SEM micrographs of rhizome and bud portions of bamboo culms were also recorded. We found very high CO2 effluxes from culm surface, nodes and buds of bamboos. Positive gas pressure and very high concentrations of CO2 were observed inside hollow sections of bamboos. The CO2 effluxes observed from bamboos were very high compared to their carbon sequestration potential. Our measurements suggest that bamboos are net emitters of CO2 during their lifespan. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

  20. Systematic framework for carbon dioxide capture and utilization processes to reduce the global carbon dioxide emissions

    DEFF Research Database (Denmark)

    Frauzem, Rebecca; Plaza, Cristina Calvera; Gani, Rafiqul

    information-data on various carbon dioxide emission sources and available capture-utilization technologies; the model and solution libraries [2]; and the generic 3-stage approach for determining more sustainable solutions [3] through superstructure (processing networks) based optimization – adopted for global...... need to provide, amongst other options: useful data from in-house databases on carbon dioxide emission sources; mathematical models from a library of process-property models; numerical solvers from library of implemented solvers; and, work-flows and data-flows for different benefit scenarios...... to be investigated. It is useful to start by developing a prototype framework and then augmenting its application range by increasing the contents of its databases, libraries and work-flows and data-flows. The objective is to present such a prototype framework with its implemented database containing collected...

  1. Miniaturized remission sensor for carbon dioxide detection

    International Nuclear Information System (INIS)

    Martan, T; Will, M

    2010-01-01

    Recently, optical sensors for detection of carbon dioxide (CO 2 ) have been explored for variety of applications in chemistry, industry, and medicine. This paper deals with the development of a planar optical remission sensor employing a dye immobilized in a polymer layer designed for gaseous CO 2 detection. The principle of CO 2 detection was based on colour changes of Tetraethylammonium Cresol red immobilized in a special composed polymer layer that was irradiated by LED diodes. Absorption properties of the dye were changed due to its chemical reaction with CO 2 and corresponding colour changes were detected by PIN diodes. These changes were analyzed by using a PC-controlled board connected by USB. The sensitivity, response time, and the detection limit of the remission sensor were characterized.

  2. Carbon dioxide: Global warning for nephrologists.

    Science.gov (United States)

    Marano, Marco; D'Amato, Anna; Cantone, Alessandra

    2016-09-06

    The large prevalence of respiratory acid-base disorders overlapping metabolic acidosis in hemodialysis population should prompt nephrologists to deal with the partial pressure of carbon dioxide (pCO2) complying with the reduced bicarbonate concentration. What the most suitable formula to compute pCO2 is reviewed. Then, the neglected issue of CO2 content in the dialysis fluid is under the spotlight. In fact, a considerable amount of CO2 comes to patients' bloodstream every hemodialysis treatment and "acidosis by dialysate" may occur if lungs do not properly clear away this burden of CO2. Moreover, vascular access recirculation may be easy diagnosed by detecting CO2 in the arterial line of extracorporeal circuit if CO2-enriched blood from the filter reenters arterial needle.

  3. Carbon dioxide neutral, integrated biofuel facility

    Energy Technology Data Exchange (ETDEWEB)

    Powell, E.E.; Hill, G.A. [Department of Chemical Engineering, University of Saskatchewan, 57 Campus Drive, Saskatoon, Saskatchewan, S7N 5A9 (Canada)

    2010-12-15

    Algae are efficient biocatalysts for both capture and conversion of carbon dioxide in the environment. In earlier work, we have optimized the ability of Chlorella vulgaris to rapidly capture CO{sub 2} from man-made emission sources by varying environmental growth conditions and bioreactor design. Here we demonstrate that a coupled biodiesel-bioethanol facility, using yeast to produce ethanol and photosynthetic algae to produce biodiesel, can result in an integrated, economical, large-scale process for biofuel production. Each bioreactor acts as an electrode for a coupled complete microbial fuel cell system; the integrated cultures produce electricity that is consumed as an energy source within the process. Finally, both the produced yeast and spent algae biomass can be used as added value byproducts in the feed or food industries. Using cost and revenue estimations, an IRR of up to 25% is calculated using a 5 year project lifespan. (author)

  4. Carbon dioxide removal with inorganic membranes

    Energy Technology Data Exchange (ETDEWEB)

    Judkins, R.R.; Fain, D.E. [Oak Ridge National Laboratory, TN (United States)

    1993-12-31

    The increasing concentrations of greenhouse gases, particularly carbon dioxide, in the atmosphere has sparked a great deal of interest in the removal of CO{sub 2} from flue gases of fossil fueled plants. Presently, several techniques for the removal of CO{sub 2} are considered to have potential, but are lacking in practicality. For example, amine scrubbing of flue gas streams is potential, but are lacking in practically. For example, amine scrubbing of flue gas streams is effective in removing CO{sub 2}, but costs are high; efficiency suffers; and other acid gases must be removed prior to amine stripping. Membrane systems for CO{sub 2} removal are held in high regard, and inorganic, particularly ceramic, membranes offer the potential for high temperature, thus energy saving, removal.

  5. Heat transfer coeffcient for boiling carbon dioxide

    DEFF Research Database (Denmark)

    Knudsen, Hans Jørgen Høgaard; Jensen, Per Henrik

    1997-01-01

    Heat transfer coefficient and pressure drop for boiling carbon dioxide (R744) flowing in a horizontal pipe has been measured. The pipe is heated by condensing R22 outside the pipe. The heat input is supplied by an electrical heater wich evaporates the R22. With the heat flux assumed constant over...... the whole surface and with measured temperature difference between the inner surface and the evaporation temperature a mean heat transfer coefficient is calculated. The calculated heat transfer coefficient has been compared with the Chart Correlation of Shah. The Chart Correlation predicts too low heat...... transfer coefficient but the ratio between the measured and the calculated heat transfer coefficient is nearly constant and equal 1.9. With this factor the correlation predicts the measured data within 14% (RMS). The pressure drop is of the same order as the measuring uncertainty and the pressure drop has...

  6. Carbon Dioxide in Arable Soil Profiles

    DEFF Research Database (Denmark)

    Chirinda, Ngoni; Plauborg, Finn; Heckrath, Goswin Johann

    2014-01-01

    on the comparability of results obtained using different methods is limited. We therefore aimed to compare the dynamics in soil CO2 concentrations obtained from an automated system (GMP343 sensors) to those from a manually operated measurement system (i.e., soil gas sampled using stainless steel needles and rods......Carbon dioxide (CO2) concentrations in arable soil profiles are influenced by autotrophic and heterotrophic respiration as well as soil physical properties that regulate gas transport. Whereas different methods have been used to assess dynamics of soil CO2 concentrations, our understanding...... systems. Within the measurement range for the GMP343 sensors (0-20,000 ppm), mean results from the two systems were similar within the plough layer at the upslope (P = 0.060) and footslope (P = 0.139) position, and also below the plough layer at the upslope position (P = 0.795). However, results from...

  7. Coiled tubing drilling with supercritical carbon dioxide

    Science.gov (United States)

    Kolle , Jack J.

    2002-01-01

    A method for increasing the efficiency of drilling operations by using a drilling fluid material that exists as supercritical fluid or a dense gas at temperature and pressure conditions existing at a drill site. The material can be used to reduce mechanical drilling forces, to remove cuttings, or to jet erode a substrate. In one embodiment, carbon dioxide (CO.sub.2) is used as the material for drilling within wells in the earth, where the normal temperature and pressure conditions cause CO.sub.2 to exist as a supercritical fluid. Supercritical carbon dioxide (SC--CO.sub.2) is preferably used with coiled tube (CT) drilling equipment. The very low viscosity SC--CO.sub.2 provides efficient cooling of the drill head, and efficient cuttings removal. Further, the diffusivity of SC--CO.sub.2 within the pores of petroleum formations is significantly higher than that of water, making jet erosion using SC--CO.sub.2 much more effective than water jet erosion. SC--CO.sub.2 jets can be used to assist mechanical drilling, for erosion drilling, or for scale removal. A choke manifold at the well head or mud cap drilling equipment can be used to control the pressure within the borehole, to ensure that the temperature and pressure conditions necessary for CO.sub.2 to exist as either a supercritical fluid or a dense gas occur at the drill site. Spent CO.sub.2 can be vented to the atmosphere, collected for reuse, or directed into the formation to aid in the recovery of petroleum.

  8. Carbon Dioxide Mitigation Benefit of High-Speed Railway in Terms of Carbon Tax

    Directory of Open Access Journals (Sweden)

    Fu Yanbing

    2013-01-01

    Full Text Available This paper calculates the carbon dioxide mitigation benefit of high-speed railway based on the carbon dioxide tax policy. We define the carbon dioxide emission system boundary for high-speed railway in its whole life cycle and estimate the life cycle carbon dioxide inventories during its construction, application, and recovery stages. And then we establish a theoretical model to calculate the life cycle carbon dioxide mitigation quantity for high-speed railway when compared with road transport and then calculate its carbon dioxide mitigation benefit. The numerical example shows that the carbon dioxide mitigation benefit of high-speed railway is better than that of road transport from the whole life cycle perspective.

  9. Biomass fuels - effects on the carbon dioxide budget

    International Nuclear Information System (INIS)

    Eriksson, H.; Hallsby, G.

    1992-02-01

    It is highly desirable that the effects on the carbon dioxide balance of alternative energy sources are evaluated. Two important alternatives studied in Sweden are the extraction of logging residues left in the forest and willow production on farmland. Considered in isolation, a conversion from stem-wood harvest to whole-tree harvest has a negative effect on the carbon dioxide balance, because the amount of soil organic matter decreases. With the assumption that it takes 20 years for the logging residues to decompose, the net decrease in emissions that would result from the replacement of fossil fuels by logging residues appear moderate after 20 years. However, it will grow significantly as time passes. After 100 years with an annual combustion of logging residues the emissions are 12% of those associated with the production of an equivalent amount of energy through oil combustion. Corresponding values for 300 and 500 years are 4% and 2.5% respectively. In less than 100 years there should be a considerable reduction in the Swedish CO 2 -C emissions even if only every second new logging residue-produced TWH replaces a fossil-fuel-produced TWh. From a long-term perspective, effects on carbon reservoirs in Sweden, caused by conversions to whole-tree harvesting in forestry and to willow production on redundant farmland, can be considered negligible in terms of their influence on the carbon dioxide budget of Sweden. The orders of magnitude of influencing fluxes is exemplified in the following: The annual production of 50 TWh, whereof 40 TWh from logging residues, 8 TWh from willow and 2 TWh from annual crops is estimated to cause a total net decrease of the carbon reservoirs within Sweden corresponding to 32 Tg CO 2 -C, whereas the annual production of 50 TWh from oil combustion should emit 1200 Tg CO 2 -C in 300 years, 2000 Tg CO 2 -C in 500 years and so on. (au). 17 refs., 4 tabs

  10. Intraosseous Venography with Carbon Dioxide in Percutaneous Vertebroplasty: Carbon Dioxide Retention in Renal Veins

    International Nuclear Information System (INIS)

    Komemushi, Atsushi; Tanigawa, Noboru; Kariya, Shuji; Kojima, Hiroyuki; Shomura, Yuzo; Tokuda, Takanori; Nomura, Motoo; Terada, Jiro; Kamata, Minoru; Sawada, Satoshi

    2008-01-01

    The objective of the present study was to determine the frequency of gas retention in the renal vein following carbon dioxide intraosseous venography in the prone position and, while citing references, to examine its onset mechanisms. All percutaneous vertebroplasties performed at our hospital from January to December 2005 were registered and retrospectively analyzed. Of 43 registered procedures treating 79 vertebrae, 28 procedures treating 54 vertebrae were analyzed. Vertebral intraosseous venography was performed using carbon dioxide as a contrast agent in all percutaneous vertebroplasty procedures. In preoperative and postoperative vertebral CT, gas retention in the renal vein and other areas was assessed. Preoperative CT did not show gas retention (0/28 procedures; 0%). Postoperative CT confirmed gas retention in the renal vein in 10 of the 28 procedures (35.7%). Gas retention was seen in the right renal vein in 8 procedures (28.6%), in the left renal vein in 5 procedures (17.9%), in the left and right renal veins in 3 procedures (10.7%), in vertebrae in 22 procedures (78.6%), in the soft tissue around vertebrae in 14 procedures (50.0%), in the spinal canal in 12 procedures (42.9%), and in the subcutaneous tissue in 5 procedures (17.9%). In conclusion, in our study, carbon dioxide gas injected into the vertebra frequently reached and remained in the renal vein.

  11. Amazon River carbon dioxide outgassing fuelled by wetlands

    NARCIS (Netherlands)

    Abril, G.; Martinez, J.M.; Artigas, L.F.; Moreira-Turcq, P.; Benedetti, M.F.; Vidal, L.; Meziane, T.; Kim, J.-H.; Bernardes, M.C.; Savoye, N.; Deborde, J.; Souza, E.L.; Alberic, P.; de Souza, M.F.L.; Roland, F.

    2014-01-01

    River systems connect the terrestrial biosphere, the atmosphere and the ocean in the global carbon cycle(1). A recent estimate suggests that up to 3 petagrams of carbon per year could be emitted as carbon dioxide (CO2) from global inland waters, offsetting the carbon uptake by terrestrial

  12. Absorption of carbon dioxide and isotope exchange rate of carbon in a reaction system between carbon dioxide and carbamic acid

    International Nuclear Information System (INIS)

    Takeshita, Kenji; Kitamoto, Asashi

    1985-01-01

    The performance of isotope separation of carbon-13 by chemical exchange between carbon dioxide and carbamic acid was studied. The working fluid used in the study was a solution of DNBA, (C 4 H 9 ) 2 NH and n-octane mixture. Factors related to the isotope exchange rate were measured, such as the absorption rate of carbon dioxide into the solution of DNBA and n-octane, the isotope exchange rate and the separation factor in the reaction between CO 2 and carbamic acid. The absorption of CO 2 into the working fluid was the sum of chemical absorption by DNBA and physical absorption by n-octane. The absorption of carbon dioxide into the working fluid was negligible at temperatures over 90 0 C, but increased gradually at lower temperatures. Carbon dioxide was absorbed into DNBA by chemical absorption, and DNBA was converted to carbamic acid by the reaction. The reaction for synthesis and decomposition of carbamic acid was reversible. The separation factor in equilibrium reached a large value at lower temperatures. The isotope exchange rate between gas and liquid was proportional to the product of the concentration of carbamic acid and the concentration of CO 2 by physical absorption. The isotope separation of carbon by chemical exchange reaction is better operated under the conditions of lower temperature and higher pressure. (author)

  13. Air-sea exchange of carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Bakker, D C.E.; De Baar, H J.W.; De Jong, E; Koning, F A [Netherlands Institute for Sea Research NIOZ, Den Burg Texel (Netherlands)

    1996-12-31

    The greenhouse gas carbon dioxide is emitted by anthropogenic activities. The oceans presumably serve as a net sink for 17 to 39% of these emissions. The objective of this project is to quantify more accurately the locality, seasonality and magnitude of the net air-sea flux of CO2 with emphasis on the South Atlantic Ocean. In situ measurements of the fugacity of CO2 in surface water and marine air, of total dissolved inorganic carbon, alkalinity and of air-sea exchange of CO2 have been made at four Atlantic crossings, in the Southern Ocean, in a Norwegian fjord and in the Dutch coastal zone. Skin temperature was detected during several of the cruises. The data collected in the course of the project support and refine previous findings. Variability of dissolved CO2 in surface water is related in a complex way to biological and physical factors. The carbonate equilibria cause dissolved gaseous CO2 to react in an intricate manner to disturbances. Dissolved gaseous CO2 hardly ever attains equilibrium with the atmospheric CO2 content by means of air-sea exchange, before a new disturbance occurs. Surface water fCO2 changes could be separated in those caused by seasonal warming and those by biological uptake in a Southern Ocean spring. Incorporation of a thermal skin effect and a change of the wind speed interval strongly increased the small net oceanic uptake for the area. The Atlantic crossings point to a relationship between water mass history and surface water CO2 characteristics. In particular, current flow and related heat fluxes leave their imprint on the concentration dissolved gaseous CO2 and on air-sea exchange. In the Dutch coastal zone hydrography and inorganic carbon characteristics of the water were heterogeneous, which yielded variable air-sea exchange of CO2. figs., tabs., refs.

  14. A strategic decision-making model considering the social costs of carbon dioxide emissions for sustainable supply chain management.

    Science.gov (United States)

    Tseng, Shih-Chang; Hung, Shiu-Wan

    2014-01-15

    Incorporating sustainability into supply chain management has become a critical issue driven by pressures from governments, customers, and various stakeholder groups over the past decade. This study proposes a strategic decision-making model considering both the operational costs and social costs caused by the carbon dioxide emissions from operating such a supply chain network for sustainable supply chain management. This model was used to evaluate carbon dioxide emissions and operational costs under different scenarios in an apparel manufacturing supply chain network. The results showed that the higher the social cost rate of carbon dioxide emissions, the lower the amount of the emission of carbon dioxide. The results also suggested that a legislation that forces the enterprises to bear the social costs of carbon dioxide emissions resulting from their economic activities is an effective approach to reducing carbon dioxide emissions. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Modeling and calculation of open carbon dioxide refrigeration system

    International Nuclear Information System (INIS)

    Cai, Yufei; Zhu, Chunling; Jiang, Yanlong; Shi, Hong

    2015-01-01

    Highlights: • A model of open refrigeration system is developed. • The state of CO 2 has great effect on Refrigeration capacity loss by heat transfer. • Refrigeration capacity loss by remaining CO 2 has little relation to the state of CO 2 . • Calculation results are in agreement with the test results. - Abstract: Based on the analysis of the properties of carbon dioxide, an open carbon dioxide refrigeration system is proposed, which is responsible for the situation without external electricity unit. A model of open refrigeration system is developed, and the relationship between the storage environment of carbon dioxide and refrigeration capacity is conducted. Meanwhile, a test platform is developed to simulation the performance of the open carbon dioxide refrigeration system. By comparing the theoretical calculations and the experimental results, several conclusions are obtained as follows: refrigeration capacity loss by heat transfer in supercritical state is much more than that in two-phase region and the refrigeration capacity loss by remaining carbon dioxide has little relation to the state of carbon dioxide. The results will be helpful to the use of open carbon dioxide refrigeration

  16. The formation of ethane from carbon dioxide under cold plasma

    International Nuclear Information System (INIS)

    Zhang Xiuling; Zhang Lin; Dai Bin; Gong Weimin; Liu Changhou

    2001-01-01

    Pulsed-corona plasma has been used as a new method for ethane dehydrogenation at low temperature and normal pressure using carbon dioxide as an oxidant. The effect of carbon dioxide content in the feed, power input, and flow rate of the reactants on the ethane dehydrogenation has been investigated. The experimental results show that the conversion of ethane increases with the increasing in the amount of carbon dioxide in the feed. The yield of ethylene and acetylene decreases with the increasing in the yield of carbon monoxide, indicating that the increased carbon dioxide leads to the part of ethylene and acetylene being oxidized to carbon monoxide. Power input is primarily an electrical parameter in pulsed-corona plasma, which plays an important role in reactant conversion and product formation. When the power input reaches 16 W, ethane conversion is 41.0% and carbon dioxide conversion is 26.3%. The total yield of ethylene and acetylene is 15.6%. The reduced flow rate of feed improves the conversion of ethane, carbon dioxide and the yield of acetylene, and induces carbon deposit as well

  17. Forest management techniques for carbon dioxide storage

    Energy Technology Data Exchange (ETDEWEB)

    Fujimori, Takao [Forestry and Forest Products Research Inst., Tsukuba, Ibaraki (Japan)

    1993-12-31

    In the global ecosystem concerning carbon dioxide content in the atmosphere, the forest ecosystem plays an important role. In effect, the ratio of forest biomass to total terrestrial biomass is about 90%, and the ratio of carbon stored in the forest biomass to that in the atmosphere is two thirds. When soils and detritus of forests are added, there is more C stored in forests than in the atmosphere, about 1.3 times or more. Thus, forests can be regarded as the great holder of C on earth. If the area of forest land on the earth is constantly maintained and forests are in the climax stage, the uptake of C and the release of C by and from the forests will balance. In this case, forests are neither sinks nor sources of CO{sub 2} although they store a large amount of C. However, when forests are deforested, they become a source of C; through human activities, forests have become a source of C. According to a report by the IPCC, 1.6{+-}1.2 PgC is annually added to the atmosphere by deforestation. According to the FAO (1992), the area of land deforested annually in the tropics from 1981 to 1990 was 16.9 x 10{sup 6} ha. This value is nearly half the area of Japanese land. The most important thing for the CO{sub 2} environment concerning forests is therefore how to reduce deforestation and to successfully implement a forestation or reforestation.

  18. Carbon dioxide warming of the early Earth

    Science.gov (United States)

    Arrhenius, G.

    1997-01-01

    Svante Arrhenius' research in atmospheric physics extended beyond the recent past and the near future states of the Earth, which today are at the center of sociopolitical attention. His plan encompassed all of the physical phenomena known at the time to relate to the formation and evolution of stars and planets. His two-volume textbook on cosmic physics is a comprehensive synopsis of the field. The inquiry into the possible cause of the ice ages and the theory of selective wavelength filter control led Arrhenius to consider the surface states of the other terrestrial planets, and of the ancient Earth before it had been modified by the emergence of life. The rapid escape of hydrogen and the equilibration with igneous rocks required that carbon in the early atmosphere prevailed mainly in oxidized form as carbon dioxide, together with other photoactive gases exerting a greenhouse effect orders of magnitude larger than in our present atmosphere. This effect, together with the ensuing chemical processes, would have set the conditions for life to evolve on our planet, seeded from spores spreading through an infinite Universe, and propelled, as Arrhenius thought, by stellar radiation pressure.

  19. Kinetics of absorption of carbon dioxide in aqueous amine and carbonate solutions with carbonic anhydrase

    NARCIS (Netherlands)

    Penders-van Elk, Nathalie J. M. C.; Hamborg, Espen S.; Huttenhuis, Patrick J. G.; Fradette, Sylvie; Carley, Jonathan A.; Versteeg, Geert F.

    In the present work the absorption of carbon dioxide in aqueous N-methyldiethanolamine (MDEA) and aqueous sodium carbonate with and without carbonic anhydrase (CA) was studied in a stirred cell contactor in the temperature range 298-333 K. The CA was present as free enzyme and is compared to the

  20. Chemoselective alternating copolymerization of limonene dioxide and carbon dioxide : a new highly functional aliphatic epoxy polycarbonate

    NARCIS (Netherlands)

    Li, C.; Sablong, R.J.; Koning, C.E.

    The alternating copolymerization of biorenewable limonene dioxide with carbon dioxide (CO2) catalyzed by a zinc β-diiminate complex is reported. The chemoselective reaction results in linear amorphous polycarbonates that carry pendent methyloxiranes and exhibit glass transition temperatures (Tg) up

  1. Carbon dioxide fluid-flow modeling and injectivity calculations

    Science.gov (United States)

    Burke, Lauri

    2011-01-01

    At present, the literature lacks a geologic-based assessment methodology for numerically estimating injectivity, lateral migration, and subsequent long-term containment of supercritical carbon dioxide that has undergone geologic sequestration into subsurface formations. This study provides a method for and quantification of first-order approximations for the time scale of supercritical carbon dioxide lateral migration over a one-kilometer distance through a representative volume of rock. These calculations provide a quantified foundation for estimating injectivity and geologic storage of carbon dioxide.

  2. Carbon dioxide and nisin act synergistically on Listeria monocytogenes

    DEFF Research Database (Denmark)

    Nilsson, Lilian; Chen, Y.H.; Chikindas, M.L.

    2000-01-01

    This paper examines the synergistic action of carbon dioxide and nisin on Listeria monocytogenes Scott A wild-type and nisin-resistant (Nis(r)) cells grown in broth at 4 degrees C. Carbon dioxide extended the lag phase and decreased the specific growth rate of both strains, but to a greater degree...... for cultures in CO2. This synergism between nisin and CO2 was examined mechanistically by following the leakage of carboxyfluorescein (CF) from listerial liposomes. Carbon dioxide enhanced nisin-induced CF leakage, indicating that the synergistic action of CO2 and nisin occurs at the cytoplasmic membrane...

  3. Production and emission of methane and carbon dioxide by ruminants

    International Nuclear Information System (INIS)

    Chouinard, Y.

    2003-01-01

    Animal digestion is responsible for the production of both carbon dioxide and methane, while breathing produces only carbon dioxide. The author described the digestion mechanism of ruminants, explaining that they produce higher levels of methane and carbon dioxide than other animals. Fermentation stoichiometry of ruminants was also discussed along with the influence that diet has on methane production. It was noted that methane production can be decreased by increasing animal productivity, or by using ionophore antibiotics and long chain fatty acids. Test results from each of these methods have revealed side effects and none appears to be applicable for the time being. 10 refs., 1 tab., 1 fig

  4. Interaction of titanium and vanadium with carbon dioxide under heating

    International Nuclear Information System (INIS)

    Vlasyuk, R.Z.; Kurovskij, V.Ya.; Lyapunov, V.P.; Radomysel'skij, I.D.

    1986-01-01

    The methods of gravitmetric and X-ray phase analysis as well as analysis of composition of gases in the heating chamber have been used to investigate the mechanism of titanium and vanadium interaction with carbon dioxide in the 300-1000 deg C temperature range. The analogy of mechanisms of the interaction of titanium and vanadium with carbon dioxide in oxides production on the metal surface with subsequent carbidizing treatment at temperatures above 800 deg C is shown. Temperature limits of material operation on the base of titanium or vanadium in carbon dioxide must not exceed 400 or 600 deg C, respectively

  5. Understanding how individuals perceive carbon dioxide. Implications for acceptance of carbon dioxide capture and storage

    Energy Technology Data Exchange (ETDEWEB)

    Itaoka, K.; Saito, A. [Mizuho Information and Research Institute, Tokyo (Japan); Paukovic, M.; De Best-Waldhober, M. [ECN Policy Studies, Petten (Netherlands); Dowd, A.M.; Jeanneret, T.; Ashworth, P.; James, M. [The Global CCS Institute, Canberra (Australia)

    2012-06-15

    Carbon dioxide capture and storage (CCS) presents one potential technological solution for mitigating the atmospheric emission of carbon dioxide sources. However, CCS is a relatively new technology with associated uncertainties and perceived risks. For this reason, a growing body of research now focuses on public perceptions and potential for societal acceptance of CCS technology. Almost all explanations of CCS technology make reference to carbon dioxide, with an assumption that the general public understands CO2. It has become apparent that the general public’s knowledge and understanding of CO2’s properties influences how they engage with CO2 emitting industries and CCS technologies. However, surprisingly little research has investigated public perceptions, knowledge, and understanding of CO2. This investigation attempts to fill that gap. This report describes an investigation of how citizens of three countries (Japan, Australia, and the Netherlands) perceive CO2. Furthermore, it attempts to relate individual perceptions of CO2 to perceptions of CCS, and to determine how information provision about the underlying properties and characteristics of CO2 influences individual attitudes towards low carbon energy options, particularly CCS. In brief, the research had four ultimate aims. It aimed to: Explore the public’s knowledge and understanding of the properties of CO2; Examine the influence of that knowledge on their perceptions of CO2 and CCS; Investigate how information provision about the underlying properties and characteristics of CO2 influences individual attitudes towards CCS; and Identify if any differences between countries exist in relation to values and beliefs, knowledge of CO2’s properties, and CCS perceptions.

  6. A comparative analysis of carbon dioxide displacement rates for euthanasia of the ferret.

    Science.gov (United States)

    Fitzhugh, Dawn C; Parmer, Amanda; Shelton, Larry J; Sheets, James T

    2008-02-01

    Though carbon dioxide asphyxiation is a common method of euthanasia for laboratory animals, species-specific guidelines have not been established for this procedure in the domestic ferret (Mustela putorius furo). The authors investigated the efficacy and stress effects of carbon dioxide euthanasia in 24 ferrets that had participated in previous experimental protocols. They euthanized ferrets by placing them in cages that were either prefilled with carbon dioxide or gradually filled at a displacement rate of 10%, 20% or 50% of the cage volume per min. Blinded observers subjectively evaluated ferret distress. Prefilling the cage or filling it at a rate of 50% volume per min resulted in less time to recumbency and to last breath than did filling the cage at a slower displacement rate. Slower carbon dioxide displacement rates also caused an increase in ferret blood glucose concentrations, which may indicate distress. Overall, observers found that prefilling the euthanasia cage caused the least stress to ferrets.

  7. Synthesis pf dimethyl carbonate in supercritical carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Ballivet-Tkatchenko, D.; Plasseraud, L. [Universite de Bourgogne-UFR Sciences et Techniques, Dijon (France). Lab. de Synthese et Electrosynthese Organometalliques]. E-mail: ballivet@u-bourgogne.fr; Ligabue, R.A. [Pontificia Univ. Catolica do Rio Grande do Sul, Porto Alegre, RS (Brazil). Dept. de Quimica Pura

    2006-01-15

    The reactivity of carbon dioxide with methanol to form dimethyl carbonate was studied in the presence of the n-butylmethoxytin compounds n-Bu{sub 3}SnOCH{sub 3}, n-Bu{sub 2}Sn(OCH{sub 3}){sub 2}, and [n-Bu{sub 2}(CH{sub 3}O)Sn]{sub 2}O. The reaction occurred under solventless conditions at 423 K and was produced by an increase in CO{sub 2} pressure. This beneficial effect is primarily attributed to phase behavior. The mass transfer under liquid-vapor biphasic conditions was not limiting when the system reached the supercritical state for a CO{sub 2} pressure higher than 16 MPa. Under these conditions, CO{sub 2} acted as a reactant and a solvent. (author)

  8. Membranes for separation of carbon dioxide

    Science.gov (United States)

    Ku, Anthony Yu-Chung [Rexford, NY; Ruud, James Anthony [Delmar, NY; Ramaswamy, Vidya [Niskayuna, NY; Willson, Patrick Daniel [Latham, NY; Gao, Yan [Niskayuna, NY

    2011-03-01

    Methods for separating carbon dioxide from a fluid stream at a temperature higher than about 200.degree. C. with selectivity higher than Knudsen diffusion selectivity include contacting a porous membrane with the fluid stream to preferentially transport carbon dioxide. The porous membrane includes a porous support and a continuous porous separation layer disposed on a surface of the porous support and extending between the fluid stream and the porous support layer. The porous support comprises alumina, silica, zirconia, stabilized zirconia, stainless steel, titanium, nickel-based alloys, aluminum-based alloys, zirconium-based alloys or a combination thereof. Median pore size of the porous separation layer is less than about 10 nm, and the porous separation layer comprises titania, MgO, CaO, SrO, BaO, La.sub.2O.sub.3, CeO.sub.2, HfO.sub.2, Y.sub.2O.sub.3, VO.sub.z, NbO.sub.z, TaO.sub.z, ATiO.sub.3, AZrO.sub.3, AAl.sub.2O.sub.4, A.sup.1FeO.sub.3, A.sup.1MnO.sub.3, A.sup.1CoO.sub.3, A.sup.1NiO.sub.3, A.sup.2HfO.sub.3, A.sup.3 CeO.sub.3, Li.sub.2ZrO.sub.3, Li.sub.2SiO.sub.3, Li.sub.2TiO.sub.3, Li.sub.2HfO.sub.3, A.sup.4N.sup.1.sub.yO.sub.z, Y.sub.xN.sup.1.sub.yO.sub.z, La.sub.xN.sup.1.sub.yO.sub.z, HfN.sup.2.sub.yO.sub.z, or a combination thereof; wherein A is La, Mg, Ca, Sr or Ba; A.sup.1 is La, Ca, Sr or Ba; A.sup.2 is Ca, Sr or Ba; A.sup.3 is Sr or Ba; A.sup.4 is Mg, Ca, Sr, Ba, Ti or Zr; N.sup.1 is V, Nb, Ta, Cr, Mo, W, Mn, Si or Ge; N.sup.2 is V, Mo, W or Si; x is 1 or 2; y ranges from 1 to 3; and z ranges from 2 to 7.

  9. A metal-free electrocatalyst for carbon dioxide reduction to multi-carbon hydrocarbons and oxygenates

    Science.gov (United States)

    Wu, Jingjie; Ma, Sichao; Sun, Jing; Gold, Jake I.; Tiwary, ChandraSekhar; Kim, Byoungsu; Zhu, Lingyang; Chopra, Nitin; Odeh, Ihab N.; Vajtai, Robert; Yu, Aaron Z.; Luo, Raymond; Lou, Jun; Ding, Guqiao; Kenis, Paul J. A.; Ajayan, Pulickel M.

    2016-01-01

    Electroreduction of carbon dioxide into higher-energy liquid fuels and chemicals is a promising but challenging renewable energy conversion technology. Among the electrocatalysts screened so far for carbon dioxide reduction, which includes metals, alloys, organometallics, layered materials and carbon nanostructures, only copper exhibits selectivity towards formation of hydrocarbons and multi-carbon oxygenates at fairly high efficiencies, whereas most others favour production of carbon monoxide or formate. Here we report that nanometre-size N-doped graphene quantum dots (NGQDs) catalyse the electrochemical reduction of carbon dioxide into multi-carbon hydrocarbons and oxygenates at high Faradaic efficiencies, high current densities and low overpotentials. The NGQDs show a high total Faradaic efficiency of carbon dioxide reduction of up to 90%, with selectivity for ethylene and ethanol conversions reaching 45%. The C2 and C3 product distribution and production rate for NGQD-catalysed carbon dioxide reduction is comparable to those obtained with copper nanoparticle-based electrocatalysts. PMID:27958290

  10. A metal-free electrocatalyst for carbon dioxide reduction to multi-carbon hydrocarbons and oxygenates

    Science.gov (United States)

    Wu, Jingjie; Ma, Sichao; Sun, Jing; Gold, Jake I.; Tiwary, Chandrasekhar; Kim, Byoungsu; Zhu, Lingyang; Chopra, Nitin; Odeh, Ihab N.; Vajtai, Robert; Yu, Aaron Z.; Luo, Raymond; Lou, Jun; Ding, Guqiao; Kenis, Paul J. A.; Ajayan, Pulickel M.

    2016-12-01

    Electroreduction of carbon dioxide into higher-energy liquid fuels and chemicals is a promising but challenging renewable energy conversion technology. Among the electrocatalysts screened so far for carbon dioxide reduction, which includes metals, alloys, organometallics, layered materials and carbon nanostructures, only copper exhibits selectivity towards formation of hydrocarbons and multi-carbon oxygenates at fairly high efficiencies, whereas most others favour production of carbon monoxide or formate. Here we report that nanometre-size N-doped graphene quantum dots (NGQDs) catalyse the electrochemical reduction of carbon dioxide into multi-carbon hydrocarbons and oxygenates at high Faradaic efficiencies, high current densities and low overpotentials. The NGQDs show a high total Faradaic efficiency of carbon dioxide reduction of up to 90%, with selectivity for ethylene and ethanol conversions reaching 45%. The C2 and C3 product distribution and production rate for NGQD-catalysed carbon dioxide reduction is comparable to those obtained with copper nanoparticle-based electrocatalysts.

  11. Carbon ion pump for removal of carbon dioxide from combustion gas and other gas mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Aines, Roger D.; Bourcier, William L.

    2014-08-19

    A novel method and system of separating carbon dioxide from flue gas is introduced. Instead of relying on large temperature or pressure changes to remove carbon dioxide from a solvent used to absorb it from flue gas, the ion pump method, as disclosed herein, dramatically increases the concentration of dissolved carbonate ion in solution. This increases the overlying vapor pressure of carbon dioxide gas, permitting carbon dioxide to be removed from the downstream side of the ion pump as a pure gas. The ion pumping may be obtained from reverse osmosis, electrodialysis, thermal desalination methods, or an ion pump system having an oscillating flow in synchronization with an induced electric field.

  12. Carbon ion pump for removal of carbon dioxide from combustion gas and other gas mixtures

    Science.gov (United States)

    Aines, Roger D.; Bourcier, William L.

    2010-11-09

    A novel method and system of separating carbon dioxide from flue gas is introduced. Instead of relying on large temperature or pressure changes to remove carbon dioxide from a solvent used to absorb it from flue gas, the ion pump method, as disclosed herein, dramatically increases the concentration of dissolved carbonate ion in solution. This increases the overlying vapor pressure of carbon dioxide gas, permitting carbon dioxide to be removed from the downstream side of the ion pump as a pure gas. The ion pumping may be obtained from reverse osmosis, electrodialysis, thermal desalination methods, or an ion pump system having an oscillating flow in synchronization with an induced electric field.

  13. Blended polymer materials extractable with supercritical carbon dioxide

    Science.gov (United States)

    Cai, Mei

    Supercritical carbon dioxide is drawing more and more attention because of its unique solvent properties along with being environmentally friendly. Historically most of the commercial interests of supercritical carbon dioxide extraction are in the food industry, pharmaceutical industry, environmental preservation and polymer processing. Recently attention has shifted from the extraction of relatively simple molecules to more complex systems with a much broader range of physical and chemical transformations. However the available data show that a lot of commercially valuable substances are not soluble in supercritical carbon dioxide due to their polar structures. This fact really limits the application of SCF extraction technology to much broader industrial applications. Therefore, the study of a polymer's solubility in a given supercritical fluid and its thermodynamic behavior becomes one of the most important research topics. The major objective of this dissertation is to develop a convenient and economic way to enhance the polymer's solubility in supercritical carbon dioxide. Further objective is to innovate a new process of making metal casting parts with blended polymer materials developed in this study. The key technique developed in this study to change a polymer's solubility in SCF CO2 is to thermally blend a commercially available and CO2 non-soluble polymer material with a low molecular weight CO2 soluble organic chemical that acts as a co-solute. The mixture yields a plastic material that can be completely solubilized in SCF CO2 over a range of temperatures and pressures. It also exhibits a variety of physical properties (strength, hardness, viscosity, etc.) depending on variations in the mixture ratio. The three organic chemicals investigated as CO2 soluble materials are diphenyl carbonate, naphthalene, and benzophenone. Two commercial polymers, polyethylene glycol and polystyrene, have been investigated as CO2 non-soluble materials. The chemical

  14. In-pot evaluation of different composted and pelletized organic fertilizers on soil carbon dioxide efflux and basal respiration

    Science.gov (United States)

    Opsi, Francesca; Cavallo, Eugenio; Cocco, Stefania; Corti, Giuseppe

    2013-04-01

    Climate change is one of the most important environmental problems and it is closely related to concentration changes of greenhouse gases (GHG) in the atmosphere, mainly due to anthropogenic activities. As a consequence, measures have been taken to reduce GHG emissions, some of which are associated with agriculture, as well as to the enhancement of soil carbon storage. Modern intensive farming activities have also raised problems related to the safe disposal of large volume of animal waste, such as pig slurry, where the excessive land spreading can lead to water pollution and GHG evolution to the atmosphere. Composting is a great environmentally sustainable option for recycling agricultural by-products, and pelletisation is a promising technology to reduce the large volume of mature composted material in pelleted fertilizers, more suitable for long-distance transport. This study consisted of a pot-incubation experience carried out in a greenhouse of the National Research Council of Italy, under controlled conditions. The aim of the research was to investigate the effect of a composted swine solid fraction (CS, 13% w/w) and swine solid fraction blended with sawdust and composted (CSS, 9% w/w), both also as a result of pelletisation process (CSP, 12% w/w and CSSP, 8% w/w, respectively), on soil organic matter mineralization and basal respiration. Results were obtained by monitoring CO2 efflux, basal respiration and microbial biomass C on amended soil, freshly collected in a vineyard planted on a Typic Ustorthent, fine-loamy, mixed, calcareous, mesic. Samples, adjusted and maintained to about 50-60% of water holding capacity, were conditioned at 25±3 °C for 31 days of incubation. The CO2 fluxes showed a high production at the initial stage of incubation, where differences among treatments were well-rendered. CSSP produced the highest values, while CSS showed values as lower as about 45%. Intermediate values, and similar to those found in the soil sample used as

  15. A histopathologic evaluation of the Plasma Skin Regeneration System (PSR) versus a standard carbon dioxide resurfacing laser in an animal model.

    Science.gov (United States)

    Fitzpatrick, R; Bernstein, E; Iyer, S; Brown, D; Andrews, P; Penny, K

    2008-02-01

    A variety of high energy, pulsed, and scanned carbon dioxide lasers are available to perform cutaneous resurfacing. Rhytec has developed a device for skin regeneration that utilizes energy delivered via a burst of nitrogen plasma. This study was undertaken to benchmark the energy outputs of the plasma skin regeneration device as compared to an ultra-short pulsed carbon dioxide laser (the control device). The two systems were compared for time to complete healing, and the healing response post-treatment. Three Yucatan mini-pigs were utilized for this study. Following anesthesia, five experimental sites were marked along the skin atop the psoas muscle on each side of the spine. Treatment was applied using either the plasma skin regeneration system or the carbon dioxide laser, with one site remaining untreated as a control. Biopsies were taken from all treatment sites 0, 2, 7, 14, 30, and 60 days following treatment and processed to hematoxylin-eosin staining. Histopathologic examination was performed by observers blinded as to the treatment conditions. Skin treated with the plasma skin regeneration device showed a wider range of tissue effects across the energy settings used as compared to the laser treatment. All treatment sites had clinically regenerated epidermis by 7 days after treatment, with active cellular response below the D/E junction noted at the day 30 time-point at energies ranging from 2 to 4 J. The Rhytec PSR system provides an attractive alternative to standard CO2 laser with good remodeling of tissue architecture. Epidermis regenerated after PSR treatment shows a smoother surface profile than adjacent untreated tissue.

  16. 49 CFR 195.4 - Compatibility necessary for transportation of hazardous liquids or carbon dioxide.

    Science.gov (United States)

    2010-10-01

    ... hazardous liquids or carbon dioxide. 195.4 Section 195.4 Transportation Other Regulations Relating to... necessary for transportation of hazardous liquids or carbon dioxide. No person may transport any hazardous liquid or carbon dioxide unless the hazardous liquid or carbon dioxide is chemically compatible with both...

  17. Electrochemical Reactor for Producing Oxygen From Carbon Dioxide, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — An electrochemical reactor is proposed by MicroCell Technologies, LLC to electrochemically reduce carbon dioxide to oxygen. In support of NASA's advanced life...

  18. Carbon dioxide inhalation treatments of neurotic anxiety. An overview.

    Science.gov (United States)

    Wolpe, J

    1987-03-01

    A lucky chance more than 30 years ago revealed the remarkable efficacy of single inhalations of high concentrations of carbon dioxide in eliminating or markedly reducing free-floating anxiety. The reduction of anxiety lasts for days, weeks, or longer--well beyond the persistence of carbon dioxide in the body. The effects are explicable on the hypothesis that free-floating anxiety is anxiety conditioned to continuously present sources of stimulation, such as background noise or the awareness of space or time, and that the anxiety response habit is weakened when the anxiety is inhibited by the competition of responses that carbon dioxide induces. More recently, it has become apparent that inhalations of carbon dioxide, applied in a different manner, are effective in overcoming maladaptive anxiety responses to specific stimuli, e.g., social stimuli. The substance is also proving to be a valuable resource in the treatment of the common variety of panic attacks.

  19. Monthly Carbon Dioxide in Troposphere (AIRS on AQUA)

    Data.gov (United States)

    National Aeronautics and Space Administration — Carbon dioxide (CO2) is an important greenhouse gas released through natural processes such as respiration and volcano eruptions and through huma activities such as...

  20. Studies on carbon dioxide system in central Arabian sea

    Digital Repository Service at National Institute of Oceanography (India)

    AnilKumar, N.; Singbal, S.Y.S.

    significantly with depth Bicarbonate ion is quantitatively the major component of the carbon dioxide system The observed vertical distributions are discussed in terms of biological and geochemical processes in the sea...

  1. Energy costs of carbon dioxide concentrating mechanisms in aquatic organisms

    Czech Academy of Sciences Publication Activity Database

    Raven, John A.; Beardall, J.; Giordano, Mario

    2014-01-01

    Roč. 121, 2-3 (2014), s. 111-124 ISSN 0166-8595 Institutional support: RVO:61388971 Keywords : carbon dioxide * environmental change * radiation Subject RIV: EE - Microbiology, Virology Impact factor: 3.502, year: 2014

  2. Quantitative aspects of oxygen and carbon dioxide exchange ...

    African Journals Online (AJOL)

    Quantitative aspects of oxygen and carbon dioxide exchange through the ... ceratophthalmus (Crustacea: Decapoda) during rest and exercise in water and ... intersects zero time on the x-axis, indicating rapid gas exchange at the lung surface.

  3. Carbon dioxide and water vapour characteristics on the west coast ...

    Indian Academy of Sciences (India)

    Carbon dioxide, water vapour, air temperature and wind measurements at 10 Hz sampling rate were carried out over the ... seasonal and annual variations in the CO2 bal- ance. Hence, it is .... motion below produced by shear stress near the.

  4. Gas flaring: Carbon dioxide contribution to global warming ...

    African Journals Online (AJOL)

    Journal Home > Vol 20, No 2 (2016) > ... The quantitative method of analysis showed that carbon dioxide from gas ... gas flaring cause environmental degradation, health risks and constitute financial loss to the local oil producing communities.

  5. ISLSCP II Air-Sea Carbon Dioxide Gas Exchange

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains the calculated net ocean-air carbon dioxide (CO2) flux and sea-air CO2 partial pressure (pCO2) difference. The estimates are based on...

  6. Carbon dioxide and nitrous oxide in the North Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    DileepKumar, M.; Naqvi, S.W.A; Jayakumar, D.A; George, M.D.; Narvekar, P.V.; DeSousa, S

    The understanding of biogeochemical cycling of carbon dioxide and nitrous oxide in the oceans is essential for predicting the fate of anthropogenically emitted components. The North Indian Ocean, with its diverse regimes, provides us with a natural...

  7. Gas Flaring: Carbon dioxide Contribution to Global Warming ...

    African Journals Online (AJOL)

    PROF HORSFALL

    emissions resulting from high consumption of fossil fuels. Flaring been a ... method of analysis showed that carbon dioxide from gas flaring constitute 1% of the total ... Although of these, methane is potentially the most .... in some gas plants.

  8. Drying of supercritical carbon dioxide with membrane processes

    NARCIS (Netherlands)

    Lohaus, Theresa; Scholz, Marco; Koziara, Beata; Benes, Nieck Edwin; Wessling, Matthias

    2015-01-01

    In supercritical extraction processes regenerating the supercritical fluid represents the main cost constraint. Membrane technology has potential for cost efficient regeneration of water-loaded supercritical carbon dioxide. In this study we have designed membrane-based processes to dehydrate

  9. A Carbon Dioxide Laser Bibliography, 1964-1969,

    Science.gov (United States)

    A bibliography concerning carbon dioxide lasers has been compiled covering the period 1964 through 1969. The chronologically listed references have also been catalogued into an author index and a subject index. (Author)

  10. Elevated carbon dioxide: impacts on soil and plant water relations

    National Research Council Canada - National Science Library

    Kirkham, M. B

    2011-01-01

    .... Focusing on this critical issue, Elevated Carbon Dioxide: Impacts on Soil and Plant Water Relations presents research conducted on field-grown sorghum, winter wheat, and rangeland plants under elevated CO2...

  11. Precision remote sensor for oxygen and carbon dioxide, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Mesa Photonics proposes development of a passive optical sensor for simultaneous high-precision measurement of oxygen and carbon dioxide profiles within the full...

  12. Evaluation of low-cost electro-chemical sensors for environmental monitoring of ozone, nitrogen dioxide, and carbon monoxide.

    Science.gov (United States)

    Afshar-Mohajer, Nima; Zuidema, Christopher; Sousan, Sinan; Hallett, Laura; Tatum, Marcus; Rule, Ana M; Thomas, Geb; Peters, Thomas M; Koehler, Kirsten

    2018-02-01

    Development of an air quality monitoring network with high spatio-temporal resolution requires installation of a large number of air pollutant monitors. However, state-of-the-art monitors are costly and may not be compatible with wireless data logging systems. In this study, low-cost electro-chemical sensors manufactured by Alphasense Ltd. for detection of CO and oxidative gases (predominantly O 3 and NO 2 ) were evaluated. The voltages from three oxidative gas sensors and three CO sensors were recorded every 2.5 sec when exposed to controlled gas concentrations in a 0.125-m 3 acrylic glass chamber. Electro-chemical sensors for detection of oxidative gases demonstrated sensitivity to both NO 2 and O 3 with similar voltages recorded when exposed to equivalent environmental concentrations of NO 2 or O 3 gases, when evaluated separately. There was a strong linear relationship between the recorded voltages and target concentrations of oxidative gases (R 2 > 0.98) over a wide range of concentrations. Although a strong linear relationship was also observed for CO concentrations below 12 ppm, a saturation effect was observed wherein the voltage only changes minimally for higher CO concentrations (12-50 ppm). The nonlinear behavior of the CO sensors implied their unsuitability for environments where high CO concentrations are expected. Using a manufacturer-supplied shroud, sensors were tested at 2 different flow rates (0.25 and 0.5 Lpm) to mimic field calibration of the sensors with zero air and a span gas concentration (2 ppm NO2 or 15 ppm CO). As with all electrochemical sensors, the tested devices were subject to drift with a bias up to 20% after 9 months of continuous operation. Alphasense CO sensors were found to be a proper choice for occupational and environmental CO monitoring with maximum concentration of 12 ppm, especially due to the field-ready calibration capability. Alphasense oxidative gas sensors are usable only if it is valuable to know the sum of

  13. Carbon dioxide removal in gas treating processes

    International Nuclear Information System (INIS)

    Lidal, H.

    1992-06-01

    The main contribution of this work is the development of a simple and reliable modelling technique on carbon dioxide removal describing the vapor-liquid equilibria of CO 2 in aqueous alkanolamine solutions. By making use of measured pH data, the author has circumvented the problem of estimating interaction parameters, activity coefficients, and equilibrium constants in the prediction of vapor-liquid equilibria. The applicability of the model is best demonstrated on the tertiary amine system using MDEA. For this system, the VLE is accurately represented for temperatures in the range 25 to 140 o C, for CO 2 loadings from 0.001 to 1 mol/mol, and for amine molarities usually encountered in acid gas treating processes. The absorption of CO 2 into solutions containing the sterically hindered amine AMP, is also well described by the model. The equilibrium of CO 2 in mixed solvents containing a glycol (TEG,DEG) and an alkonolamine (MEA,DEA) has been measured at temperatures encountered in the absorption units. An equilibrium model has been developed for the CO 2 /TEG/MEA system for estimation of CO 2 partial pressures, covering loadings and temperatures for both absorption and desorption conditions. An important spin-off of the work described is that two new experimental set-ups have been designed and built. 154 refs., 38 figs., 22 tabs

  14. Euthanasia of neonatal mice with carbon dioxide

    Science.gov (United States)

    Pritchett, K.; Corrow, D.; Stockwell, J.; Smith, A.

    2005-01-01

    Exposure to carbon dioxide (CO2) is the most prevalent method used to euthanize rodents in biomedical research. The purpose of this study was to determine the time of CO2 exposure required to euthanize neonatal mice (0 to 10 days old). Multiple groups of mice were exposed to 100% CO 2 for time periods between 5 and 60 min. Mice were placed in room air for 10 or 20 min after CO2 exposure, to allow for the chance of recovery. If mice recovered at one time point, a longer exposure was examined. Inbred and outbred mice were compared. Results of the study indicated that time to death varied with the age of the animals and could be as long as 50 min on the day of birth and differed between inbred and outbred mice. Institutions euthanizing neonatal mice with CO2 may wish to adjust their CO 2 exposure time periods according the age of the mice and their genetic background. Copyright 2005 by the American Association for Laboratory Animal Science.

  15. Periorbital area rejuvenation using carbon dioxide therapy.

    Science.gov (United States)

    Paolo, Fioramonti; Nefer, Fallico; Paola, Parisi; Nicolò, Scuderi

    2012-09-01

    Different conservative and surgical approaches are used for periorbital region rejuvenation, but none of them is effective in the treatment of the medial third of the lower eyelid. The present study is designed to assess the effectiveness of carboxytherapy in the treatment of wrinkles on the median and medial region of the lower eyelid and dark circles around the eyes. From January 2008 to December 2010, 90 patients with moderate to severe periorbital wrinkles and/or dark circles underwent subcutaneous injections of CO(2) once a week for 7 weeks. Patients were assessed before and 2 months after the treatment through photographic documentation and the compilation of visual analog scales. At the end of the study period, patients reported a reduction of facial fine lines and wrinkles as well as a decrease in periorbital hyperpigmentation. A few side effects were observed but they were all transient and did not require discontinuation of treatment. Carbon dioxide therapy results as an effective noninvasive modality for the rejuvenation of the periorbital area. © 2012 Wiley Periodicals, Inc.

  16. Carbon dioxide removal in gas treating processes

    Energy Technology Data Exchange (ETDEWEB)

    Lidal, H

    1992-06-01

    The main contribution of this work is the development of a simple and reliable modelling technique on carbon dioxide removal describing the vapor-liquid equilibria of CO{sub 2} in aqueous alkanolamine solutions. By making use of measured pH data, the author has circumvented the problem of estimating interaction parameters, activity coefficients, and equilibrium constants in the prediction of vapor-liquid equilibria. The applicability of the model is best demonstrated on the tertiary amine system using MDEA. For this system, the VLE is accurately represented for temperatures in the range 25 to 140{sup o}C, for CO{sub 2} loadings from 0.001 to 1 mol/mol, and for amine molarities usually encountered in acid gas treating processes. The absorption of CO{sub 2} into solutions containing the sterically hindered amine AMP, is also well described by the model. The equilibrium of CO{sub 2} in mixed solvents containing a glycol (TEG,DEG) and an alkonolamine (MEA,DEA) has been measured at temperatures encountered in the absorption units. An equilibrium model has been developed for the CO{sub 2}/TEG/MEA system for estimation of CO{sub 2} partial pressures, covering loadings and temperatures for both absorption and desorption conditions. An important spin-off of the work described is that two new experimental set-ups have been designed and built. 154 refs., 38 figs., 22 tabs.

  17. Acute carbon dioxide avoidance in Caenorhabditis elegans.

    Science.gov (United States)

    Hallem, Elissa A; Sternberg, Paul W

    2008-06-10

    Carbon dioxide is produced as a by-product of cellular respiration by all aerobic organisms and thus serves for many animals as an important indicator of food, mates, and predators. However, whether free-living terrestrial nematodes such as Caenorhabditis elegans respond to CO2 was unclear. We have demonstrated that adult C. elegans display an acute avoidance response upon exposure to CO2 that is characterized by the cessation of forward movement and the rapid initiation of backward movement. This response is mediated by a cGMP signaling pathway that includes the cGMP-gated heteromeric channel TAX-2/TAX-4. CO2 avoidance is modulated by multiple signaling molecules, including the neuropeptide Y receptor NPR-1 and the calcineurin subunits TAX-6 and CNB-1. Nutritional status also modulates CO2 responsiveness via the insulin and TGFbeta signaling pathways. CO2 response is mediated by a neural circuit that includes the BAG neurons, a pair of sensory neurons of previously unknown function. TAX-2/TAX-4 function in the BAG neurons to mediate acute CO2 avoidance. Our results demonstrate that C. elegans senses and responds to CO2 using multiple signaling pathways and a neural network that includes the BAG neurons and that this response is modulated by the physiological state of the worm.

  18. Medium temperature carbon dioxide gas turbine reactor

    International Nuclear Information System (INIS)

    Kato, Yasuyoshi; Nitawaki, Takeshi; Muto, Yasushi

    2004-01-01

    A carbon dioxide (CO 2 ) gas turbine reactor with a partial pre-cooling cycle attains comparable cycle efficiencies of 45.8% at medium temperature of 650 deg. C and pressure of 7 MPa with a typical helium (He) gas turbine reactor of GT-MHR (47.7%) at high temperature of 850 deg. C. This higher efficiency is ascribed to: reduced compression work around the critical point of CO 2 ; and consideration of variation in CO 2 specific heat at constant pressure, C p , with pressure and temperature into cycle configuration. Lowering temperature to 650 deg. C provides flexibility in choosing materials and eases maintenance through the lower diffusion leak rate of fission products from coated particle fuel by about two orders of magnitude. At medium temperature of 650 deg. C, less expensive corrosion resistant materials such as type 316 stainless steel are applicable and their performance in CO 2 have been proven during extensive operation in AGRs. In the previous study, the CO 2 cycle gas turbomachinery weight was estimated to be about one-fifth compared with He cycles. The proposed medium temperature CO 2 gas turbine reactor is expected to be an alternative solution to current high-temperature He gas turbine reactors

  19. Carbon dioxide removal and the futures market

    Science.gov (United States)

    Coffman, D.'Maris; Lockley, Andrew

    2017-01-01

    Futures contracts are exchange-traded financial instruments that enable parties to fix a price in advance, for later performance on a contract. Forward contracts also entail future settlement, but they are traded directly between two parties. Futures and forwards are used in commodities trading, as producers seek financial security when planning production. We discuss the potential use of futures contracts in Carbon Dioxide Removal (CDR) markets; concluding that they have one principal advantage (near-term price security to current polluters), and one principal disadvantage (a combination of high price volatility and high trade volume means contracts issued by the private sector may cause systemic economic risk). Accordingly, we note the potential for the development of futures markets in CDR, but urge caution about the prospects for market failure. In particular, we consider the use of regulated markets: to ensure contracts are more reliable, and that moral hazard is minimised. While regulation offers increased assurances, we identify major insufficiencies with this approach—finding it generally inadequate. In conclusion, we suggest that only governments can realistically support long-term CDR futures markets. We note existing long-term CDR plans by governments, and suggest the use of state-backed futures for supporting these assurances.

  20. Carbon dioxide balneotherapy and cardiovascular disease

    Science.gov (United States)

    Pagourelias, Efstathios D.; Zorou, Paraskevi G.; Tsaligopoulos, Miltiadis; Athyros, Vasilis G.; Karagiannis, Asterios; Efthimiadis, Georgios K.

    2011-09-01

    Carbon dioxide (CO2) balneotherapy is a kind of remedy with a wide spectrum of applications which have been used since the Middle Ages. However, its potential use as an adjuvant therapeutic option in patients with cardiovascular disease is not yet fully clarified. We performed a thorough review of MEDLINE Database, EMBASE, ISI WEB of Knowledge, COCHRANE database and sites funded by balneotherapy centers across Europe in order to recognize relevant studies and aggregate evidence supporting the use of CO2 baths in various cardiovascular diseases. The three main effects of CO2 hydrotherapy during whole body or partial immersion, including decline in core temperature, an increase in cutaneous blood flow, and an elevation of the score on thermal sensation, are analyzed on a pathophysiology basis. Additionally, the indications and contra-indications of the method are presented in an evidence-based way, while the need for new methodologically sufficient studies examining the use of CO2 baths in other cardiovascular substrates is discussed.

  1. Supercritical fluid carbon dioxide extraction of actinides

    International Nuclear Information System (INIS)

    Rao, Ankita; Tomar, B.S.

    2016-01-01

    Supercritical fluid extraction (SFE) is a process akin to liquid-liquid or solvent extraction where a Supercritical fluid (SCF) is contacted with a solid/ liquid matrix for the purpose of separating the component of interest from the original matrix. Carbon dioxide is a preferred choice as supercritical fluid (SCF) owing to its moderate critical parameter (P c = 7.38 MPa and T c = 304.1K) coupled with radiation and chemical stability, non toxic nature and low cost. Despite widespread applications for extraction of organic compounds and associated advantages especially liquid waste minimization, the SFE of metal ions was left unexplored for quite some time, as direct metal ion extraction is inefficient due charge neutralization requirement and weak solute-solvent interaction. Neutral SCF soluble metal-ligand complexation is imperative and SFE of actinides was reported only in 1994. Several studies have been carried out on SFE of uranium, thorium and plutonium from nitric acid medium employing different sets of ligands (organophosphorus, diketones, amides). Especially attractive is the possibility of direct dissolution and extraction of actinides employing ligand-acid adducts (like TBP.HNO 3 adduct) from solid matrices of different stages of nuclear fuel cycle viz. ores, spent nuclear fuels and radioactive wastes. Also, partitioning of actinides from fission products has been explored in spent nuclear fuel. These studies on supercritical fluid extraction of actinides indicate a more efficient and environmentally sustainable technology. (author)

  2. Slurried solid media for simultaneous water purification and carbon dioxide removal from gas mixtures

    Science.gov (United States)

    Aines, Roger D.; Bourcier, William L.; Viani, Brian

    2013-01-29

    A slurried solid media for simultaneous water purification and carbon dioxide removal from gas mixtures includes the steps of dissolving the gas mixture and carbon dioxide in water providing a gas, carbon dioxide, water mixture; adding a porous solid media to the gas, carbon dioxide, water mixture forming a slurry of gas, carbon dioxide, water, and porous solid media; heating the slurry of gas, carbon dioxide, water, and porous solid media producing steam; and cooling the steam to produce purified water and carbon dioxide.

  3. POSSIBILITIES OF CARBON DIOXIDE FIXATION BY MICROALGAE IN REFINERY

    OpenAIRE

    Šingliar, Michal; Mikulec, Jozef; Kušnir, Patrik; Polakovičova, Gabriela

    2013-01-01

    Capture and sequestration of carbon dioxide is one of the most critical challenges today for businesses and governments worldwide. Thousands of emitting power plants and industries worldwide face this costly challenge – reduce the CO2 emissions or pay penalties. One possibility for carbon dioxide sequestration is its fixation in microalgae. Microalgae can sequester CO2 from flue gases emitted from fossil fuel-fired refinery plants and units, thereby reducing emissions of a major greenhouse ga...

  4. Decontamination of radioactive clothing using microemulsion in carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Jaeryong; Jang, Jina; Park, Kwangheon; Kim, Hongdoo; Kim, Hakwon [Kyunghee Univ., Seoul (Korea, Republic of); Yim, Sanghak; Yoon, Weonseob [Ulchin Nuclear Power Site, Ulchin (Korea, Republic of)

    2006-07-01

    Nuclear power is intrinsically a clean energy source due to its high energy density and low generation of waste. However, as the nuclear industry grows, a variety of radioactive wastes are increased gradually. Major subjects include contaminated components, tools, equipment, containers and facilities as well as nuclear waste such as uranium scrap and radioactive clothing. The radioactive waste can be classified by its creation. There are Trans-Uranium Nuclides (TRU), Fission Products (FP) and corrosion products. Nuclear decontamination has become an important issue in the nuclear industry. The conventional methods have some problems such as the production of secondary wastes and the use of toxic solvents. We need to develop a new method of decontamination and suggest a use of microemulsion in carbon dioxide to overcome these disadvantages. The microemulsion is the clear solution that contains the water, surfactant and carbon dioxide. The surfactant surrounded the droplet into carbon dioxide and this state is thermodynamically stable. That is, the microemulsion has a structure similar to that of a conventional water-based surfactant system. Generally, the size of droplet is about 5 {approx} 10nm. The microemulsion is able to decontaminate radioactive waste so that the polar substance is removed by water and the non-polar substance is removed by carbon dioxide. After the decontamination process, the microemulsion is separated easily to surfactant and water by decreasing the pressure under the cloud point. This way, only radioactive wastes are left in the system. Cleaned carbon dioxide is then collected and reused. Thus, there are no secondary wastes. Carbon dioxide is considered an alternative process medium. This is because it is non-toxic, non-flammable, inexpensive and easy to handle. Additionally, the tunable properties of carbon dioxide through pressure and temperature control are versatile for use in extracting organic materials. In this paper, we examine the

  5. Carbon dioxide efflux from leaves in light and darkness

    Energy Technology Data Exchange (ETDEWEB)

    Holmgren, P; Jarvis, P G

    1967-01-01

    The efflux of carbon dioxide in light and darkness was measured at low ambient CO/sub 2/ concentrations in leaves of Rumex acetosa. Light carbon dioxide production (photorespiration) was found to depend on irradiance and to differ from dark production as to the response to temperature and ambient concentrations of O/sub 2/ and CO/sub 2/. These observations support previously made suggestions that photorespiration follows a different metabolic pathway to dark respiration.

  6. Tethered catalysts for the hydration of carbon dioxide

    Science.gov (United States)

    Valdez, Carlos A; Satcher, Jr., Joe H; Aines, Roger D; Wong, Sergio E; Baker, Sarah E; Lightstone, Felice C; Stolaroff, Joshuah K

    2014-11-04

    A system is provided that substantially increases the efficiency of CO.sub.2 capture and removal by positioning a catalyst within an optimal distance from the air-liquid interface. The catalyst is positioned within the layer determined to be the highest concentration of carbon dioxide. A hydrophobic tether is attached to the catalyst and the hydrophobic tether modulates the position of the catalyst within the liquid layer containing the highest concentration of carbon dioxide.

  7. Decontamination of radioactive clothing using microemulsion in carbon dioxide

    International Nuclear Information System (INIS)

    Yoo, Jaeryong; Jang, Jina; Park, Kwangheon; Kim, Hongdoo; Kim, Hakwon; Yim, Sanghak; Yoon, Weonseob

    2006-01-01

    Nuclear power is intrinsically a clean energy source due to its high energy density and low generation of waste. However, as the nuclear industry grows, a variety of radioactive wastes are increased gradually. Major subjects include contaminated components, tools, equipment, containers and facilities as well as nuclear waste such as uranium scrap and radioactive clothing. The radioactive waste can be classified by its creation. There are Trans-Uranium Nuclides (TRU), Fission Products (FP) and corrosion products. Nuclear decontamination has become an important issue in the nuclear industry. The conventional methods have some problems such as the production of secondary wastes and the use of toxic solvents. We need to develop a new method of decontamination and suggest a use of microemulsion in carbon dioxide to overcome these disadvantages. The microemulsion is the clear solution that contains the water, surfactant and carbon dioxide. The surfactant surrounded the droplet into carbon dioxide and this state is thermodynamically stable. That is, the microemulsion has a structure similar to that of a conventional water-based surfactant system. Generally, the size of droplet is about 5 ∼ 10nm. The microemulsion is able to decontaminate radioactive waste so that the polar substance is removed by water and the non-polar substance is removed by carbon dioxide. After the decontamination process, the microemulsion is separated easily to surfactant and water by decreasing the pressure under the cloud point. This way, only radioactive wastes are left in the system. Cleaned carbon dioxide is then collected and reused. Thus, there are no secondary wastes. Carbon dioxide is considered an alternative process medium. This is because it is non-toxic, non-flammable, inexpensive and easy to handle. Additionally, the tunable properties of carbon dioxide through pressure and temperature control are versatile for use in extracting organic materials. In this paper, we examine the

  8. The Greenness of Cities: Carbon Dioxide Emissions and Urban Development

    OpenAIRE

    Glaeser, Edward L.; Kahn, Matthew E.

    2008-01-01

    Carbon dioxide emissions may create significant social harm because of global warming, yet American urban development tends to be in low density areas with very hot summers. In this paper, we attempt to quantify the carbon dioxide emissions associated with new construction in different locations across the country. We look at emissions from driving, public transit, home heating, and household electricity usage. We find that the lowest emissions areas are generally in California and that the h...

  9. Seal evaluation and confinement screening criteria for beneficial carbon dioxide storage with enhanced coal bed methane recovery in the Pocahontas Basin, Virginia

    Science.gov (United States)

    Grimm, R.P.; Eriksson, K.A.; Ripepi, N.; Eble, C.; Greb, S.F.

    2012-01-01

    The geological storage of carbon dioxide in Appalachian basin coal seams is one possible sink for sequestration of greenhouse gases, with the added benefit of enhanced-coal bed methane (ECBM) recovery. The Pocahontas Basin (part of the central Appalachian Basin) of southwestern Virginia is a major coal bed methane (CBM) province with production mostly from coal beds in the Lower Pennsylvanian Pocahontas and New River formations. As part of the Southeast Regional Carbon Sequestration Partnership's Phase II research program, a CO 2-injection demonstration well was installed into Lower Pennsylvanian coal bed-methane producing strata in southwest Virginia. Samples of siliciclastic lithologies above coal beds in this Oakwood Field well, and from several other cores in the Nora Field were taken to establish a baseline of the basic confinement properties of overlying strata to test seal competency at local and regional scales.Strata above CBM-producing coal beds in the Pocahontas and New River formations consist of dark-gray shales; silty gray shales; heterolithic siltstones, sandstones, and shales; lithic sandstones, and quartzose sandstones. Standard measurements of porosity, permeability and petrography were used to evaluate potential leakage hazards and any possible secondary storage potential for typical lithologies. Both lithic- and quartz-rich sandstones exhibit only minor porosity, with generally low permeability (Member. Analyses of 1500 geophysical logs in southwest Virginia indicate that this unit is moderately thick (>50ft, 15m), laterally continuous (>3000km 2), and a homogenous shale, which coarsens upward into siltstone and sandstone, or is truncated by sandstone. Calculations from two mercury injection capillary porosimetry tests of the shale indicate that a displacement entry pressure of 207psi (1427kPa) would generate an estimated seal capacity of 1365ft (416m) of CO 2 before buoyant leakage. Scanning electron microscopy indicates a microfabric of narrow

  10. Electrocatalytic reduction of carbon dioxide to carbon monoxide and methane at an immobilized cobalt protoporphyrin

    NARCIS (Netherlands)

    Shen, J.; Kortlever, R.; Kas, Recep; Mul, Guido; Koper, M.T.M.

    2015-01-01

    The electrochemical conversion of carbon dioxide and water into useful products is a major challenge in facilitating a closed carbon cycle. Here we report a cobalt protoporphyrin immobilized on a pyrolytic graphite electrode that reduces carbon dioxide in an aqueous acidic solution at relatively low

  11. Beneficial Use of Carbon Dioxide in Precast Concrete Production

    Energy Technology Data Exchange (ETDEWEB)

    Shao, Yixin [McGill Univ., Montreal, QC (Canada)

    2014-06-26

    The feasibility of using carbon dioxide as feedstock in precast concrete production is studied. Carbon dioxide reacts with calcium compounds in concrete, producing solid calcium carbonates in binding matrix. Two typical precast products are examined for their capacity to store carbon dioxide during the production. They are concrete blocks and fiber-cement panels. The two products are currently mass produced and cured by steam. Carbon dioxide can be used to replace steam in curing process to accelerate early strength, improve the long-term durability and reduce energy and emission. For a reaction within a 24-hour process window, the theoretical maximum possible carbon uptake in concrete is found to be 29% based on cement mass in the product. To reach the maximum uptake, a special process is developed to promote the reaction efficiency to 60-80% in 4-hour carbon dioxide curing and improve the resistance to freeze-thaw cycling and sulfate ion attack. The process is also optimized to meet the project target of $10/tCO2 in carbon utilization. By the use of self-concentrating absorption technology, high purity CO2 can be produced at a price below $40/t. With low cost CO2 capture and utilization technologies, it is feasible to establish a network for carbon capture and utilization at the vicinity of carbon sources. If all block produces and panel producers in United States could adopt carbon dioxide process in their production in place of steam, carbon utilization in these two markets alone could consume more than 2 Mt CO2/year. This capture and utilization process can be extended to more precast products and will continue for years to come.

  12. Supercritical carbon dioxide for textile applications and recent developments

    Science.gov (United States)

    Eren, H. A.; Avinc, O.; Eren, S.

    2017-10-01

    In textile industry, supercritical carbon dioxide (scCO2), possessing liquid-like densities, mostly find an application on textile dyeing processes such as providing hydrophobic dyes an advantage on dissolving. Their gas-like low viscosities and diffusion properties can result in shorter dyeing periods in comparison with the conventional water dyeing process. Supercritical carbon dioxide dyeing is an anhydrous dyeing and this process comprises the usage of less energy and chemicals when compared to conventional water dyeing processes leading to a potential of up to 50% lower operation costs. The advantages of supercritical carbon dioxide dyeing method especially on synthetic fiber fabrics hearten leading textile companies to alter their dyeing method to this privileged waterless dyeing technology. Supercritical carbon dioxide (scCO2) waterless dyeing is widely known and applied green method for sustainable and eco-friendly textile industry. However, not only the dyeing but also scouring, desizing and different finishing applications take the advantage of supercritical carbon dioxide (scCO2). In this review, not only the principle, advantages and disadvantages of dyeing in supercritical carbon dioxide but also recent developments of scCO2 usage in different textile processing steps such as scouring, desizing and finishing are explained and commercial developments are stated and summed up.

  13. Phase equilibrium condition of marine carbon dioxide hydrate

    International Nuclear Information System (INIS)

    Sun, Shi-Cai; Liu, Chang-Ling; Ye, Yu-Guang

    2013-01-01

    Highlights: ► CO 2 hydrate phase equilibrium was studied in simulated marine sediments. ► CO 2 hydrate equilibrium temperature in NaCl and submarine pore water was depressed. ► Coarse-grained silica sand does not affect CO 2 hydrate phase equilibrium. ► The relationship between equilibrium temperature and freezing point was discussed. - Abstract: The phase equilibrium of ocean carbon dioxide hydrate should be understood for ocean storage of carbon dioxide. In this paper, the isochoric multi-step heating dissociation method was employed to investigate the phase equilibrium of carbon dioxide hydrate in a variety of systems (NaCl solution, submarine pore water, silica sand + NaCl solution mixture). The experimental results show that the depression in the phase equilibrium temperature of carbon dioxide hydrate in NaCl solution is caused mainly by Cl − ion. The relationship between the equilibrium temperature and freezing point in NaCl solution was discussed. The phase equilibrium temperature of carbon dioxide hydrate in submarine pore water is shifted by −1.1 K to lower temperature region than that in pure water. However, the phase equilibrium temperature of carbon dioxide hydrate in mixture samples of coarsed-grained silica sand and NaCl solution is in agreement with that in NaCl solution with corresponding concentrations. The relationship between the equilibrium temperature and freezing point in mixture samples was also discussed.

  14. Evaluation of avoided carbon dioxide emissions in cogeneration projects; Evaluacion de las emisiones evitadas de bioxido de carbono en proyectos de cogeneracion

    Energy Technology Data Exchange (ETDEWEB)

    Flores Zamudio, Jesus Antonio; Fernandez Montiel, Manuel Francisco; Alcaraz Calderon, Agustin Moises [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: jesus.flores@iie.org.mx; mffm@iie.org.mx; malcaraz@iie.org.mx

    2010-11-15

    In this paper, presents a methodology of how to calculate the emissions of CO{sub 2} (Carbon Dioxide) in cogeneration of plants for evaluate future cases with the type of fuel and fuel flow used in the plant. The methodology was in spreadsheets developed a series of stoichiometric balances. The methodology was done for three types of fossil fuels: solid, liquid and gas. The analysis is made only to the percentages of the items contained in the fuel flow automatically used and results in the combustion products in tons per hour. This method was compared with the results obtained in the software Thermoflow Inc. (Used in Gerencia de Procesos Termicos of Instituto de Investigaciones Electricas for evaluate various process systems that produce energy power) using different cogeneration systems, that is to say about the technology used emissions compared according to the amount of excess air for each type of technology and at one point before the gas cleaning systems. The results can be evaluated for emissions avoided through the fuel type used and developing a cogeneration plant compared to a conventional plant. [Spanish] En este articulo, se presenta una metodologia de como calcular las emisiones de CO{sub 2} (Bioxido de carbono) en plantas de cogeneracion, para evaluar casos a futuro por medio del tipo de combustible y flujo de combustible a utilizar en la planta. La metodologia se realizo en hojas de calculo, donde se desarrollaron una serie de balances estequiometricos. La metodologia se hizo para tres tipos de combustibles fosiles: solido, liquido y gas. El analisis se realiza con solo dar los porcentajes de los elementos que contiene el combustible y el flujo a utilizarse y automaticamente da como resultado los productos de la combustion en toneladas por hora. Esta metodologia se comparo con los resultados obtenidos en el software Thermoflow Inc. (Empleado en la Gerencia de Procesos Termicos del Instituto de Investigaciones Electricas para evaluar diversos

  15. Itegrated Test and Evaluation of a 4-Bed Molecular Sieve (4BMS) Carbon Dioxide Removtal System (CDRA), Mechanical Compressor Engineering Development Unit (EDU), and Sabitier Engineering Development Unit (EDU)

    Science.gov (United States)

    Knox, James C.; Campbell, Melissa; Murdoch, Karen; Miller, Lee A.; Jeng, Frank

    2005-01-01

    Currently on the International Space Station s (ISS) U.S. Segment, carbon dioxide (CO2) scrubbed from the cabin by a 4-Bed Molecular Sieve (4BMS) Carbon Dioxide Removal Assembly (CDRA) is vented overboard as a waste product. Likewise, the product hydrogen (H2) that will be generated by the Oxygen Generation Assembly (OGA) planned for installation will also be vented. A flight experiment has been proposed that will take the waste CO2 removed from the cabin, and via the catalytic Sabatier process, reduce it with waste H2 to generate water and methane. The water produced may provide cost and logistics savings for ISS by reducing the amount of water periodically re-supplied to orbit. To make this concept viable, a mechanical piston compressor and accumulator were developed for collecting and storing the CO2 from the CDRA. The compressor, accumulator and Sabatier system would be packaged together as one unit and referred to as the Carbon Dioxide Reduction Assembly (CRA). Testing was required to evaluate the performance of a 4BMS CDRA, compressor, accumulator, and Sabatier performance along with their operating rules when integrated together. This had been numerically modeled and simulated; however, testing was necessary to verify the results from the engineering analyses. Testing also allowed a better understanding of the practical inefficiencies and control issues involved in a fully integrated system versus the theoretical ideals in the model. This paper presents and discusses the results of an integrated engineering development unit test.

  16. Terpolymerization of ethylene, sulfur dioxide and carbon monoxide

    Science.gov (United States)

    Johnson, R.; Steinberg, M.

    This invention relates to high molecular weight terpolymer of ethylene, sulfur dioxide and carbon monoxide stable to 280/sup 0/C and containing as little as 36 mo1% ethylene and about 41 to 51 mo1% sulfur dioxide, and to the method of producing said terpolymer by irradiation of a liquid and gaseous mixture of ethylene, sulfur dioxide and carbon monoxide by means of Co-60 gamma rays or an electron beam, at a temperature of about 10 to 50/sup 0/C, and at a pressure of about 140 to 680 atmospheres, to initiate polymerization.

  17. The role of renewable bioenergy in carbon dioxide sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Kinoshita, C.M. [Hawaii Natural Energy Inst., Honolulu, HI (United States)

    1993-12-31

    The use of renewable resources represents a sound approach to producing clean energy and reducing the dependence on diminishing reserves of fossil fuels. Unfortunately, the widespread interest in renewable energy in the 1970s, spurred by escalating fossil fuel prices, subsided with the collapse of energy prices in the mid 1980s. Today, it is largely to reverse alarming environmental trends, particularly the buildup of atmospheric carbon dioxide, rather than to reduce the cost of energy, that renewable energy resources are being pursued. This discussion focuses on a specific class of renewable energy resources - biomass. Unlike most other classes of renewable energy touted for controlling atmospheric carbon dioxide concentrations, e.g., hydro, direct solar, wind, geothermal, and ocean thermal, which produce usable forms of energy while generating little or no carbon dioxide emissions, bioenergy almost always involves combustion and therefore generates carbon dioxide; however, if used on a sustained basis, bio-energy would not contribute to the build-up of atmospheric carbon dioxide because the amount released in combustion would be balanced by that taken up via photosynthesis. It is in that context, i.e., sustained production of biomass as a modern energy carrier, rather than reforestation for carbon sequestration, that biomass is being discussed here, since biomass can play a much greater role in controlling global warming by displacing fossil fuels than by being used strictly for carbon sequestration (partly because energy crop production can reduce fossil carbon dioxide emissions indefinitely, whereas under the reforestation strategy, carbon dioxide abatement ceases at forest maturity).

  18. Self-Cleaning Boudouard Reactor for Full Oxygen Recovery from Carbon Dioxide

    Science.gov (United States)

    Coutts, Janelle; Hintze, Paul E.; Muscatello, Anthony C.; Gibson, Tracy L.; Captain, James G.; Lunn, Griffin M.; Devor, Robert W.; Bauer, Brint; Parks, Steve

    2016-01-01

    Oxygen recovery from respiratory carbon dioxide is an important aspect of human spaceflight. Methods exist to sequester the carbon dioxide, but production of oxygen needs further development. The current International Space Station Carbon Dioxide Reduction System (CRS) uses the Sabatier reaction to produce water (and ultimately breathing air). Oxygen recovery is limited to 50 because half of the hydrogen used in the Sabatier reactor is lost as methane, which is vented overboard. The Bosch reaction, which converts carbon dioxide to oxygen and solid carbon is capable of recovering all the oxygen from carbon dioxide, and is the only real alternative to the Sabatier reaction. However, the last reaction in the cycle, the Boudouard reaction, produces solid carbon and the resulting carbon buildup will eventually foul the nickel or iron catalyst, reducing reactor life and increasing consumables. To minimize this fouling and increase efficiency, a number of self-cleaning catalyst designs have been created. This paper will describe recent results evaluating one of the designs.

  19. Anaesthesia for laparoscopic nephrectomy: Does end-tidal carbon dioxide measurement correlate with arterial carbon dioxide measurement?

    Science.gov (United States)

    Jayan, Nithin; Jacob, Jaya Susan; Mathew, Mohan

    2018-04-01

    Not many studies have explored the correlation between arterial carbon dioxide tension (PaCO 2 ) and end-tidal carbon dioxide tension (ETCO 2 ) in surgeries requiring pneumoperitoneum of more than 1 hour duration with the patient in non-supine position. The aim of our study was to evaluate the correlation of ETCO 2 with PaCO 2 in patients undergoing laparoscopic nephrectomy under general anaesthesia. A descriptive study was performed in thirty patients undergoing laparoscopic nephrectomy from September 2014 to August 2015. The haemodynamic parameters, minute ventilation, PaCO 2 and ETCO 2 measured at three predetermined points during the procedure were analysed. Correlation was checked using Pearson's Correlation Coefficient Test. P <0.05 was considered statistically significant. Statistical analysis of the values showed a positive correlation between ETCO 2 and PaCO 2 ( P < 0.05). Following carbon dioxide insufflation, both ETCO 2 and PaCO 2 increased by 5.4 and 6.63 mmHg, respectively, at the end of the 1 st hour. The PaCO 2 -ETCO 2 gradient was found to increase during the 1 st hour following insufflation (4.07 ± 2.05 mmHg); it returned to the pre-insufflation values in another hour (2.93 ± 1.43 mmHg). Continuous ETCO 2 monitoring is a reliable indicator of the trend in arterial CO 2 fluctuations in the American Society of Anesthesiologists Grades 1 and 2 patients undergoing laparoscopic nephrectomy under general anaesthesia.

  20. Ocean Fertilization for Sequestration of Carbon Dioxide from the Atmosphere

    Science.gov (United States)

    Boyd, Philip W.

    The ocean is a major sink for both preindustrial and anthropogenic carbon dioxide. Both physically and biogeochemically driven pumps, termed the solubility and biological pump, respectively Fig.5.1) are responsible for the majority of carbon sequestration in the ocean's interior [1]. The solubility pump relies on ocean circulation - specifically the impact of cooling of the upper ocean at high latitudes both enhances the solubility of carbon dioxide and the density of the waters which sink to great depth (the so-called deepwater formation) and thereby sequester carbon in the form of dissolved inorganic carbon (Fig.5.1). The biological pump is driven by the availability of preformed plant macronutrients such as nitrate or phosphate which are taken up by phytoplankton during photosynthetic carbon fixation. A small but significant proportion of this fixed carbon sinks into the ocean's interior in the form of settling particles, and in order to maintain equilibrium carbon dioxide from the atmosphere is transferred across the air-sea interface into the ocean (the so-called carbon drawdown) thereby decreasing atmospheric carbon dioxide (Fig.5.1).Fig.5.1

  1. Stabilization of carbon dioxide and chromium slag via carbonation.

    Science.gov (United States)

    Wu, Xingxing; Yu, Binbin; Xu, Wei; Fan, Zheng; Wu, Zucheng; Zhang, Huimin

    2017-08-01

    As the main greenhouse gas, CO 2 is considered as a threat in the context of global warming. Many available technologies to reduce CO 2 emission was about CO 2 separation from coal combustion and geological sequestration. However, how to deal with the cost-effective storage of CO 2 has become a new challenge. Moreover, chromium pollution, the treatment of which requires huge energy consumption, has attracted people's widespread attention. This study is aimed to develop the sequestration of CO 2 via chromium slag. A dynamic leaching experiment of chromium slag was designed to testify the ability of CO 2 adsorption onto chromium slag and to release Cr(VI) for stabilization. The results showed that the accumulative amounts of Cr(VI) were ca. 2.6 mg/g released from the chromium slag after 24 h of leaching. In addition, ca. 89 mg/g CO 2 was adsorbed by using pure CO 2 in the experiment at 12 h. Calcite is the only carbonate species in the post-carbonated slag analyzed by powder X-ray diffraction and thermal analysis. The approach provides the feasibility of the utilization of chromium slag and sequestration of the carbon dioxide at the same time at ordinary temperatures and pressures.

  2. It is time to put carbon dioxide to work

    Energy Technology Data Exchange (ETDEWEB)

    Lipinsky, E.S. [Battelle, Columbus, OH (United States)

    1993-12-31

    The need to control emissions of carbon dioxide into the atmosphere is the subject of vigorous debate at this time. There is growing evidence that rising levels of carbon dioxide increase global warming, with perhaps highly adverse impacts for the human economy. There are calls for carbon taxes and other harsh measures. Japan has established a national goal of holding carbon dioxide emissions in the year 2000 to 1990 levels. I hope that this conference will be a turning point in the United States position on this issue. The current major end uses for CO{sub 2} include refrigeration, beverage carbonation, soda ash production, fire fighting, and urea fertilizer production. They are all based on chemistry that would not surprise a good chemist of the 19th century. Consumption of carbon dioxide in synthesis of industrial chemicals is limited. Usually one explains low production of chemicals from a candidate feedstock in terms of poor availability, price, purity, or reactivity. We can eliminate the first three as the causes of the underutilization of carbon dioxide.

  3. Nuclear power and the carbon dioxide problem

    International Nuclear Information System (INIS)

    Bijlsma, J.J.; Blok, K.; Turkenburg, W.C.

    1989-05-01

    This study deals with the question, which contribution can be delivered by nuclear power to the redution of the emission of carbon dioxide (CO 2 ) from the power supply. The emphasis lays upon the following aspects: the emissions of CO 2 which occur in the nuclear-power cycle (the so-called indirect emission of CO 2 power plants); the amount of uranium stocks; the change of CO 2 emission caused by replacement of fossil fuels, in particular coal, by nuclear power. First an energy-analysis of the nuclear power cycle is presented. On the base of this analysis the CO 2 uranium can be calculated. The role of nuclear power in the reduction of CO 2 emission depends on the development of the final power demand. Therefore in this study two scenarios derived from the 'IIASA-low' scenario; 'low-energy'-scenario in which the world-energy consumption remains at about the same level. In the calculations the indirect emissions of CO 2 , also dependent on the ore richness and the technology used, have always been taken into account. In the calculations two uranium-reserve variants of resp. 5.7 and 30 mln. tons have been assumed. From the results of the calculations it can be concluded that whether or not taking account of the indirect emissions of CO 2 in the nuclear power cycle, has only limited effect on the calculated contribution of nuclear power to the solution of the greenhouse effect. The uranium reserves turn out to be determining for the potential contribution of nuclear power. By putting on the surely available reserve of 5.7 mln. tons, or the speculative reserve of 30 mln. tons, with the actual technology, an emission of resp. 130-140 billion and 880 billion tons CO 2 can be avoided in replacing coal. With maximal employment of improved conversion techniques these contributions may be doubled. (H.W.). 40 refs.; 13 figs.; 10 tabs

  4. Carbon Dioxide Physiological Training at NASA.

    Science.gov (United States)

    Law, Jennifer; Young, Millennia; Alexander, David; Mason, Sara S; Wear, Mary L; Méndez, Claudia M; Stanley, David; Ryder, Valerie Meyers; Van Baalen, Mary

    2017-10-01

    Astronauts undergo CO2 exposure training to recognize their symptoms that can arise acutely both on the ground and in spaceflight. This article describes acute CO2 exposure training at NASA and examines the symptoms reported by astronauts during training. In a controlled training environment, astronauts are exposed to up to 8% CO2 (60 mmHg) by a rebreathing apparatus. Symptoms are reported using a standard form. Symptom documentation forms between April 1994 and February 2012 were obtained for 130 astronauts. The number of symptoms reported per session out of the possible 24 was related to age and sex, with those older slightly more likely to report symptoms. Women reported more symptoms on average than men (men: 3.7, women: 4.7). Respiratory symptoms (90%), flushing sensation/sweating (56%), and dizziness/feeling faint/lightheadedness (43%) were the top symptoms. Only headache reached statistical significance in differences between men (13%) and women (37%) after adjustment for multiple testing. Among those with multiple training sessions, respiratory symptoms were the most consistently reported. CO2 exposure training is an important tool to educate astronauts about their potential acute CO2 symptoms. Wide interindividual and temporal variations were observed in symptoms reported during astronaut CO2 exposure training. Headache could not be relied on as a marker of acute exposure during testing since fewer than half the subjects reported it. Our results support periodic refresher training since symptoms may change over time. Further study is needed to determine the optimal interval of training to maximize symptom recognition and inform operational decisions.Law J, Young M, Alexander D, Mason SS, Wear ML, Méndez CM, Stanley D, Meyers Ryder V, Van Baalen M. Carbon dioxide physiological training at NASA. Aerosp Med Hum Perform. 2017; 88(10):897-902.

  5. Reactor design considerations in mineral sequestration of carbon dioxide

    International Nuclear Information System (INIS)

    Ityokumbul, M.T.; Chander, S.; O'Connor, William K.; Dahlin, David C.; Gerdemann, Stephen J.

    2001-01-01

    One of the promising approaches to lowering the anthropogenic carbon dioxide levels in the atmosphere is mineral sequestration. In this approach, the carbon dioxide reacts with alkaline earth containing silicate minerals forming magnesium and/or calcium carbonates. Mineral carbonation is a multiphase reaction process involving gas, liquid and solid phases. The effective design and scale-up of the slurry reactor for mineral carbonation will require careful delineation of the rate determining step and how it changes with the scale of the reactor. The shrinking core model was used to describe the mineral carbonation reaction. Analysis of laboratory data indicates that the transformations of olivine and serpentine are controlled by chemical reaction and diffusion through an ash layer respectively. Rate parameters for olivine and serpentine carbonation are estimated from the laboratory data

  6. Dissolved Carbon Dioxide in Tropical East Atlantic Surface Waters

    NARCIS (Netherlands)

    Bakker, D.C.E.; Baar, H.J.W. de; Jong, E. de

    1999-01-01

    Variability of dissolved inorganic carbon (DIC) and the fugacity of carbon dioxide (fCO2) is discussed for tropical East Atlantic surface waters in October–November 1993 and May–June 1994. High precipitation associated with the Intertropical Convergence Zone, river input and equatorial upwelling

  7. Regional carbon dioxide implications of forest bioenergy production

    NARCIS (Netherlands)

    Hudiburg, Tara W.; Law, Beverly E.; Wirth, Christian; Luyssaert, Sebastiaan

    2011-01-01

    Strategies for reducing carbon dioxide emissions include substitution of fossil fuel with bioenergy from forests, where carbon emitted is expected to be recaptured in the growth of new biomass to achieve zero net emissions, and forest thinning to reduce wildfire emissions. Here, we use forest

  8. Assessing Carbon Dioxide Emissions from Energy Use at a University

    Science.gov (United States)

    Riddell, William; Bhatia, Krishan Kumar; Parisi, Matthew; Foote, Jessica; Imperatore, John, III

    2009-01-01

    Purpose: The purpose of this paper is to assess the carbon dioxide emissions associated with electric, HVAC, and hot water use from a US university. Design/methodology/approach: First, the total on-campus electrical, natural gas and oil consumption for an entire year was assessed. For each category of energy use, the carbon associated with…

  9. Ions in carbon dioxide at an atmospheric pressure

    International Nuclear Information System (INIS)

    Ikezoe, Yasumasa; Onuki, Kaoru; Shimizu, Saburo; Nakajima, Hayato; Sato, Shoichi; Matsuoka, Shingo; Nakamura, Hirone; Tamura, Takaaki

    1985-01-01

    The formation and the subsequent reactions of positive and negative ions were observed by a time resolved atmospheric pressure ionization mass spectrometer (TRAPI) in an atmospheric pressure carbon dioxide added with small amounts of carbon monoxide and oxygen. A relatively stable ion of (44 x n) + (n >= 2) having a different reactivity from that of (CO 2 ) + sub(n) was found to be one of major ionic species in this gas system. This species was tentatively assigned as [O 2 (CO) 2 ] + (CO 2 )sub(n-2). A new reaction sequence of positive ions is proposed which can be operative in the radiolysis of carbon dioxide at 1 atm. (author)

  10. 27.12 MHz plasma generation in supercritical carbon dioxide

    International Nuclear Information System (INIS)

    Kawashima, Ayato; Toyota, Hiromichi; Nomura, Shinfuku; Takemori, Toshihiko; Mukasa, Shinobu; Maehara, Tsunehiro; Yamashita, Hiroshi

    2007-01-01

    An experiment was conducted for generating high-frequency plasma in supercritical carbon dioxide; it is expected to have the potential for applications in various types of practical processes. It was successfully generated at 6-20 MPa using electrodes mounted in a supercritical cell with a gap of 1 mm. Emission spectra were then measured to investigate the physical properties of supercritical carbon dioxide plasma. The results indicated that while the emission spectra for carbon dioxide and carbon monoxide could be mainly obtained at a low pressure, the emission spectra for atomic oxygen could be obtained in the supercritical state, which increased with the pressure. The temperature of the plasma in supercritical state was estimated to be approximately 6000-7000 K on the assumption of local thermodynamic equilibrium and the calculation results of thermal equilibrium composition in this state showed the increase of atomic oxygen by the decomposition of CO 2

  11. Sequestration of carbon dioxide with hydrogen to useful products

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Michael W. W.; Kelly, Robert M.; Hawkins, Aaron B.; Menon, Angeli Lal; Lipscomb, Gina Lynette Pries; Schut, Gerrit Jan

    2017-03-07

    Provided herein are genetically engineered microbes that include at least a portion of a carbon fixation pathway, and in one embodiment, use molecular hydrogen to drive carbon dioxide fixation. In one embodiment, the genetically engineered microbe is modified to convert acetyl CoA, molecular hydrogen, and carbon dioxide to 3-hydroxypropionate, 4-hydroxybutyrate, acetyl CoA, or the combination thereof at levels greater than a control microbe. Other products may also be produced. Also provided herein are cell free compositions that convert acetyl CoA, molecular hydrogen, and carbon dioxide to 3-hydroxypropionate, 4-hydroxybutyrate, acetyl CoA, or the combination thereof. Also provided herein are methods of using the genetically engineered microbes and the cell free compositions.

  12. Gettering of carbon dioxide by erbium thin films

    International Nuclear Information System (INIS)

    Mehrhoff, T.K.

    1980-01-01

    The interaction of carbon dioxide and erbium thin films is characterized for temperatures in the region of 300 to 900 0 C and partial pressure of carbon dioxide near 5 x 10 -7 Torr. Dynamic film pumping speeds were measured against a mercury diffusion pump of known pumping speed and conductance. A quadrupole mass spectrometer was used to monitor the carbon dioxide flow which originated from a calibrated leak in the 10 -6 standard cm 3 /s range. Data reduction was via a dedicated minicomputer with associated printer/plotter. Temperature ramp experiments with thin erbium films indicated a significant reaction above 300 0 C. The reaction was preceded by the desorption of water vapor, hydrogen and nitrogen and/or carbon monoxide from the film surface

  13. Evaluating the effects of terrestrial ecosystems, climate and carbon dioxide on weathering over geological time: a global-scale process-based approach

    Science.gov (United States)

    Taylor, Lyla L.; Banwart, Steve A.; Valdes, Paul J.; Leake, Jonathan R.; Beerling, David J.

    2012-01-01

    Global weathering of calcium and magnesium silicate rocks provides the long-term sink for atmospheric carbon dioxide (CO2) on a timescale of millions of years by causing precipitation of calcium carbonates on the seafloor. Catchment-scale field studies consistently indicate that vegetation increases silicate rock weathering, but incorporating the effects of trees and fungal symbionts into geochemical carbon cycle models has relied upon simple empirical scaling functions. Here, we describe the development and application of a process-based approach to deriving quantitative estimates of weathering by plant roots, associated symbiotic mycorrhizal fungi and climate. Our approach accounts for the influence of terrestrial primary productivity via nutrient uptake on soil chemistry and mineral weathering, driven by simulations using a dynamic global vegetation model coupled to an ocean–atmosphere general circulation model of the Earth's climate. The strategy is successfully validated against observations of weathering in watersheds around the world, indicating that it may have some utility when extrapolated into the past. When applied to a suite of six global simulations from 215 to 50 Ma, we find significantly larger effects over the past 220 Myr relative to the present day. Vegetation and mycorrhizal fungi enhanced climate-driven weathering by a factor of up to 2. Overall, we demonstrate a more realistic process-based treatment of plant fungal–geosphere interactions at the global scale, which constitutes a first step towards developing ‘next-generation’ geochemical models. PMID:22232768

  14. Biomass combustion for greenhouse carbon dioxide enrichment

    International Nuclear Information System (INIS)

    Roy, Yves; Lefsrud, Mark; Orsat, Valerie; Filion, Francis; Bouchard, Julien; Nguyen, Quoc; Dion, Louis-Martin; Glover, Antony; Madadian, Edris; Lee, Camilo Perez

    2014-01-01

    Greenhouses in northern climates have a significant heat requirement that is mainly supplied by non-renewable fuels such as heating oil and natural gas. This project's goal was the development of an improved biomass furnace able to recover the heat and the CO 2 available in the flue gas and use them in the greenhouse. A flue gas purification system was designed, constructed and installed on the chimney of a wood pellet furnace (SBI Caddy Alterna). The purification system consists of a rigid box air filter (MERV rating 14, 0.3 μm pores) followed by two sets of heating elements and a catalytic converter. The air filter removes the particulates present in the flue gas while the heating elements and catalysers transform the noxious gases into less harmful gases. Gas analysis was sampled at different locations in the system using a TESTO 335 flue gas analyzer. The purification system reduces CO concentrations from 1100 cm 3  m −3 to less than 1 cm 3  m −3 NO x from 70 to 5.5 cm 3  m −3 SO 2 from 19 cm 3  m −3 to less than 1 cm 3  m −3 and trapped particulates down to 0.3 μm with an efficiency greater than 95%. These results are satisfactory since they ensure human and plant safety after dilution into the ambient air of the greenhouse. The recuperation of the flue gas has several obvious benefits since it increases the heat usability per unit biomass and it greatly improves the CO 2 recovery of biomass heating systems for the benefit of greenhouse grown plants. - Highlights: • Biomass furnace shows high potential for greenhouse carbon dioxide enrichment. • Flue gas recuperation significantly increases the thermal efficiency of a furnace. • Catalytic converter can reduce CO and NOx below humans and plants exposure limit. • Particulates control is essential to maintain the efficiency of the catalytic conversion. • CO 2 recovery from biomass heating systems reduces farmer's reliance on fossil fuel

  15. Direct carbon dioxide emissions from civil aircraft

    Science.gov (United States)

    Grote, Matt; Williams, Ian; Preston, John

    2014-10-01

    Global airlines consume over 5 million barrels of oil per day, and the resulting carbon dioxide (CO2) emitted by aircraft engines is of concern. This article provides a contemporary review of the literature associated with the measures available to the civil aviation industry for mitigating CO2 emissions from aircraft. The measures are addressed under two categories - policy and legal-related measures, and technological and operational measures. Results of the review are used to develop several insights into the challenges faced. The analysis shows that forecasts for strong growth in air-traffic will result in civil aviation becoming an increasingly significant contributor to anthropogenic CO2 emissions. Some mitigation-measures can be left to market-forces as the key-driver for implementation because they directly reduce airlines' fuel consumption, and their impact on reducing fuel-costs will be welcomed by the industry. Other mitigation-measures cannot be left to market-forces. Speed of implementation and stringency of these measures will not be satisfactorily resolved unattended, and the current global regulatory-framework does not provide the necessary strength of stewardship. A global regulator with ‘teeth' needs to be established, but investing such a body with the appropriate level of authority requires securing an international agreement which history would suggest is going to be very difficult. If all mitigation-measures are successfully implemented, it is still likely that traffic growth-rates will continue to out-pace emissions reduction-rates. Therefore, to achieve an overall reduction in CO2 emissions, behaviour change will be necessary to reduce demand for air-travel. However, reducing demand will be strongly resisted by all stakeholders in the industry; and the ticket price-increases necessary to induce the required reduction in traffic growth-rates place a monetary-value on CO2 emissions of approximately 7-100 times greater than other common

  16. Fluid Dynamics of Carbon Dioxide Disposal into Saline Aquifers

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Julio Enrique [Univ. of California, Berkeley, CA (United States)

    2003-01-01

    Injection of carbon dioxide (CO2) into saline aquifers has been proposed as a means to reduce greenhouse gas emissions (geological carbon sequestration). Large-scale injection of CO2 will induce a variety of coupled physical and chemical processes, including multiphase fluid flow, fluid pressurization and changes in effective stress, solute transport, and chemical reactions between fluids and formation minerals. This work addresses some of these issues with special emphasis given to the physics of fluid flow in brine formations. An investigation of the thermophysical properties of pure carbon dioxide, water and aqueous solutions of CO2 and NaCl has been conducted. As a result, accurate representations and models for predicting the overall thermophysical behavior of the system CO2-H2O-NaCl are proposed and incorporated into the numerical simulator TOUGH2/ECO2. The basic problem of CO2 injection into a radially symmetric brine aquifer is used to validate the results of TOUGH2/ECO2. The numerical simulator has been applied to more complex flow problem including the CO2 injection project at the Sleipner Vest Field in the Norwegian sector of the North Sea and the evaluation of fluid flow dynamics effects of CO2 injection into aquifers. Numerical simulation results show that the transport at Sleipner is dominated by buoyancy effects and that shale layers control vertical migration of CO2. These results are in good qualitative agreement with time lapse surveys performed at the site. High-resolution numerical simulation experiments have been conducted to study the onset of instabilities (viscous fingering) during injection of CO2 into saline aquifers. The injection process can be classified as immiscible displacement of an aqueous phase by a less dense and less viscous gas phase. Under disposal conditions (supercritical CO2) the viscosity of carbon

  17. Predator-induced reduction of freshwater carbon dioxide emissions

    Science.gov (United States)

    Atwood, Trisha B.; Hammill, Edd; Greig, Hamish S.; Kratina, Pavel; Shurin, Jonathan B.; Srivastava, Diane S.; Richardson, John S.

    2013-03-01

    Predators can influence the exchange of carbon dioxide between ecosystems and the atmosphere by altering ecosystem processes such as decomposition and primary production, according to food web theory. Empirical knowledge of such an effect in freshwater systems is limited, but it has been suggested that predators in odd-numbered food chains suppress freshwater carbon dioxide emissions, and predators in even-numbered food chains enhance emissions. Here, we report experiments in three-tier food chains in experimental ponds, streams and bromeliads in Canada and Costa Rica in the presence or absence of fish (Gasterosteus aculeatus) and invertebrate (Hesperoperla pacifica and Mecistogaster modesta) predators. We monitored carbon dioxide fluxes along with prey and primary producer biomass. We found substantially reduced carbon dioxide emissions in the presence of predators in all systems, despite differences in predator type, hydrology, climatic region, ecological zone and level of in situ primary production. We also observed lower amounts of prey biomass and higher amounts of algal and detrital biomass in the presence of predators. We conclude that predators have the potential to markedly influence carbon dioxide dynamics in freshwater systems.

  18. Carbon dioxide, the feedstock for using renewable energy

    Science.gov (United States)

    Hashimoto, K.; Kumagai, N.; Izumiya, K.; Kato, Z.

    2011-03-01

    Extrapolation of world energy consumption between 1990 and 2007 to the future reveals the complete exhaustion of petroleum, natural gas, uranium and coal reserves on Earth in 2040, 2044, 2049 and 2054, respectively. We are proposing global carbon dioxide recycling to use renewable energy so that all people in the whole world can survive. The electricity will be generated by solar cell in deserts and used to produce hydrogen by seawater electrolysis at t nearby desert coasts. Hydrogen, for which no infrastructures of transportation and combustion exist, will be converted to methane at desert coasts by the reaction with carbon dioxide captured by energy consumers. Among systems in global carbon dioxide recycling, seawater electrolysis and carbon dioxide methanation have not been performed industrially. We created energy-saving cathodes for hydrogen production and anodes for oxygen evolution without chlorine formation in seawater electrolysis, and ideal catalysts for methane formation by the reaction of carbon dioxide with hydrogen. Prototype plant and industrial scale pilot plant have been built.

  19. Measures for carbon dioxide problem and utilization of energy

    International Nuclear Information System (INIS)

    Kojima, Toshinori

    1992-01-01

    As global environment problems, there are water, expansion of deserts, weather, tropical forests, wild animals, ocean pollution, nuclear waste contamination, acid rain, ozone layer and so on, and population, foods, energy, and resources are the problems surrounding them. It is clear that these origins are attributed to the development and consumption largely dependent on the intention of developed countries and the population problem of developing countries. In this report, the discharge of carbon dioxide that causes greenhouse effect and its relation with energy are discussed. The increase of carbon dioxide concentration, its release from fossil fuel, the destruction of forests, the balance of carbon on the earth, the development of new energy such as solar energy, the transport of new energy, secondary energy system and the role of carbon dioxide, the transfer to low carbon fuel and the carbon reduction treatment of fuel, the utilization of unused energy and energy price, the efficiency of energy utilization, the heightening of efficiency of energy conversion, energy conservation and the breakaway from energy wasteful use culture, and the recovery, preservation and use of discharged carbon dioxide are described. (K.I.)

  20. Measurement of carbon dioxide fluxes in a free-air carbon dioxide enrichment experiment using the closed flux chamber technique

    DEFF Research Database (Denmark)

    Selsted, Merete Bang; Ambus, Per; Michelsen, Anders

    2011-01-01

    Carbon dioxide (CO2) fluxes, composing net ecosystem exchange (NEE), ecosystem respiration (ER), and soil respiration (SR) were measured in a temperate heathland exposed to elevated CO2 by the FACE (free-air carbon enrichment) technique, raising the atmospheric CO2 concentration from c. 380 μmol...

  1. Method and aparatus for flue gas cleaning by separation and liquefaction of sulfur dioxide and carbon dioxide

    International Nuclear Information System (INIS)

    Abdelmalek, F.T.

    1992-01-01

    This patent describes a method for recovering sulfur dioxide, carbon dioxide, and cleaning flue gases emitted from power plants. It comprises: electronically treating the flue gases to neutralize its electrostatic charges and to enhance the coagulation of its molecules and particles; exchanging sensible and latent heat of the neutralized flue gases to lower its temperature down to a temperature approaching the ambient temperature while recovering its separating the flue gas in a first stage; cooling the separated enriched carbon dioxide gas fraction, after each separation stage, while removing its vapor condensate, then compressing the enriched carbon dioxide gas fraction and simultaneously cooling the compressed gas to liquefy the sulfur dioxide gas then; allowing the sulfur dioxide gas to condense, and continuously removing the liquefied sulfur dioxide; compressing he desulfurized enriched carbon dioxide fraction to further increase its pressure, and simultaneously cooling he compressed gas to liquefy the carbon dioxide gas, then; allowing the carbon dioxide gas to condense and continuously removing the liquefied carbon dioxide; allowing the light components of the flue gas to be released in a cooling tower discharge plume

  2. Wound healing in porcine skin following low-output carbon dioxide laser irradiation of the incision

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, J.K.; Garden, J.M.; Taute, P.M.; Leibovich, S.J.; Lautenschlager, E.P.; Hartz, R.S.

    1987-06-01

    Wound healing of scalpel incisions to the depth of adipose tissue closed with conventional methods was compared with closure by low-output carbon dioxide laser irradiation. In 3 Pitman-Moore minipigs wound healing was evaluated at intervals from 1 to 90 days by the following methods: clinical variables of wound healing; formation of the basement membrane components bullous pemphigoid antigen, laminin, and fibronectin; and histological evaluation of the regeneration of the epidermis, neovascularization, and elastin and collagen formation. There was no significant difference in healing between wounds closed by the various conventional methods and by the low-output carbon dioxide laser.

  3. Carbon dioxide therapy and hyaluronic acid for cosmetic correction of the nasolabial folds.

    Science.gov (United States)

    Nisi, Giuseppe; Cuomo, Roberto; Brandi, Cesare; Grimaldi, Luca; Sisti, Andrea; D'Aniello, Carlo

    2016-06-01

    The main application of hyaluronic acid filling, in esthetic medicine, is the augmentation of soft tissues. The carbon dioxide therapy, instead, improves quality and elasticity of the dermis and increases the oxygen release to the tissue through an enhancing of the Bohr's effect. The aim of the study was to compare the efficacy, tolerability, and effect duration of hyaluronic acid fillers and the use of carbon dioxide therapy plus hyaluronic acid in the cosmetic correction of nasolabial folds. Forty healthy female patients received a blinded and randomized treatment on nasolabial folds (hyaluronic acid in group A and hyaluronic acid plus subcutaneous injections of carbon dioxide in group B) for cosmetic correction of the nasolabial folds. The results were evaluated by two blinded plastic surgeons after the implant (1 week, 4 and 6 months) using a 1-5 graduated scale (GAIS), and at the same time, each patient was asked to express her opinion about the cosmetic result. Any long-term adverse reaction was reported. The blinded evaluation at 4 and 6 months from the implant shows in all patients a maintenance of a good cosmetic result higher for the side treated with carbon dioxide therapy plus hyaluronic acid. At the control visit, 6 months after the treatment, the patients treated with hyaluronic acid plus carbon dioxide therapy maintain a satisfactory esthetic result while the nasolabial fold treated only with hyaluronic acid shows, in almost all patients, a come back to pretreatment appearance. © 2016 Wiley Periodicals, Inc.

  4. Carbon dioxide stripping in aquaculture -- part III: model verification

    Science.gov (United States)

    Colt, John; Watten, Barnaby; Pfeiffer, Tim

    2012-01-01

    Based on conventional mass transfer models developed for oxygen, the use of the non-linear ASCE method, 2-point method, and one parameter linear-regression method were evaluated for carbon dioxide stripping data. For values of KLaCO2 < approximately 1.5/h, the 2-point or ASCE method are a good fit to experimental data, but the fit breaks down at higher values of KLaCO2. How to correct KLaCO2 for gas phase enrichment remains to be determined. The one-parameter linear regression model was used to vary the C*CO2 over the test, but it did not result in a better fit to the experimental data when compared to the ASCE or fixed C*CO2 assumptions.

  5. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    International Nuclear Information System (INIS)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; William J. McMichael; Douglas P. Harrison; Ya Liang

    2002-01-01

    The objective of this project is to develop a simple, inexpensive process to separate CO(sub 2) as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbents being investigated in this project are primarily alkali carbonates, and particularly sodium carbonate and potassium carbonate, which are converted to bicarbonates, through reaction with carbon dioxide and water vapor. Bicarbonates are regenerated to carbonates when heated, producing a nearly pure CO(sub 2) stream after condensation of water vapor. This quarter, electrobalance tests conducted at LSU indicated that exposure of sorbent to water vapor prior to contact with carbonation gas does not significantly increase the reaction rate. Calcined fine mesh trona has a greater initial carbonation rate than calcined sodium bicarbonate, but appears to be more susceptible to loss of reactivity under severe calcination conditions. The Davison attrition indices for Grade 5 sodium bicarbonate, commercial grade sodium carbonate and extra fine granular potassium carbonate were, as tested, outside of the range suitable for entrained bed reactor testing. Fluidized bed testing at RTI indicated that in the initial stages of reaction potassium carbonate removed 35% of the carbon dioxide in simulated flue gas, and is reactive at higher temperatures than sodium carbonate. Removals declined to 6% when 54% of the capacity of the sorbent was exhausted. Carbonation data from electrobalance testing was correlated using a shrinking core reaction model. The activation energy of the reaction of sodium carbonate with carbon dioxide and water vapor was determined from nonisothermal thermogravimetry

  6. The carbon dioxide problem - a challenge to environmental protection

    International Nuclear Information System (INIS)

    Hlubek, W.; Spalthoff, F.J.

    1989-01-01

    Over the last century, man's activities on earth have sent off trace gases into the planet's atmosphere that have been concentrating to a level posing a threat to the global climate. Since scientists particularly spotted carbon dioxide as the main contributor to what we now call the greenhouse effect, there is urgent need for measures reducing carbon dioxide emission worldwide, may be on the basis of a global convention to be signed by both the industrialised and the developing countries. The industrialised countries, which certainly are the main pollutors, also will have the technological and financial resources to respond to the challenge of global warning more directly and faster than the developing countries. The power industry's management in the FRG is taking the problem seriously and has already come out with strategies for curbing carbon dioxide emissions from fossil-fuel power plant. (orig.) [de

  7. Interaction of titanium and vanadium with carbon dioxide in heating

    International Nuclear Information System (INIS)

    Vlasyuk, R.Z.; Kurovskii, V.Y.; Lyapunov, A.P.; Radomysel'skii, I.D.

    1986-01-01

    To obtain prediction data on the change in properties of titaniumand vanadium-base powder metallurgy materials operating in a carbon dioxide atmosphere, and also to clarify the mechanism of their interaction with the gas in this work, gravimetric investigations of specimens heated at temperatures of 300-1000 C and an x-ray diffraction analysis of their surface were made and the composition of the gas in the heating chamber was studied. The results of the investigations indicate a similarity between the mechanisms of interaction of titanium and vanadium with carbon dioxide including the formation of oxides on the surface of the metal with subsequent carbidization at temperatures above 800 C. On the basis of the data obtained, it may be concluded that the operating temperature limits of titanium- or vanadium-base materials in carbon dioxide must not exceed 400 and 600 C, respectively

  8. Carbonic acid as a reserve of carbon dioxide on icy moons: The formation of carbon dioxide (CO2) in a polar environment

    International Nuclear Information System (INIS)

    Jones, Brant M.; Kaiser, Ralf I.; Strazzulla, Giovanni

    2014-01-01

    Carbon dioxide (CO 2 ) has been detected on the surface of several icy moons of Jupiter and Saturn via observation of the ν 3 band with the Near-Infrared Mapping Spectrometer on board the Galileo spacecraft and the Visible-Infrared Mapping Spectrometer on board the Cassini spacecraft. Interestingly, the CO 2 band for several of these moons exhibits a blueshift along with a broader profile than that seen in laboratory studies and other astrophysical environments. As such, numerous attempts have been made in order to clarify this abnormal behavior; however, it currently lacks an acceptable physical or chemical explanation. We present a rather surprising result pertaining to the synthesis of carbon dioxide in a polar environment. Here, carbonic acid was synthesized in a water (H 2 O)-carbon dioxide (CO 2 ) (1:5) ice mixture exposed to ionizing radiation in the form of 5 keV electrons. The irradiated ice mixture was then annealed, producing pure carbonic acid which was then subsequently irradiated, recycling water and carbon dioxide. However, the observed carbon dioxide ν 3 band matches almost exactly with that observed on Callisto; subsequent temperature program desorption studies reveal that carbon dioxide synthesized under these conditions remains in solid form until 160 K, i.e., the sublimation temperature of water. Consequently, our results suggest that carbon dioxide on Callisto as well as other icy moons is indeed complexed with water rationalizing the shift in peak frequency, broad profile, and the solid state existence on these relatively warm moons.

  9. Method and apparatus for producing food grade carbon dioxide

    International Nuclear Information System (INIS)

    Nobles, J.E.; Swenson, L.K.

    1984-01-01

    A method is disclosed of producing food grade carbon dioxide from an impure carbon dioxide source stream containing contaminants which may include light and heavy hydrocarbons (at least C 1 to C 3 ) and light sulfur compounds such as hydrogen sulfide and carbonyl sulfide as well as heavier sulfur constituents in the nature of mercaptans (RSH) and/or organic mono and disulfides (RSR and RSSR). Nitrogen, water and/or oxygen may also be present in varying amounts in the impure feed stream. The feed gas is first rectified with liquid carbon dioxide condensed from a part of the feed stream to remove heavy hydrocarbons and heavy sulfur compounds, then passed through an absorber to effect removal of the light sulfur compounds, next subjected to an oxidizing atmosphere capable of converting all of the C 2 hydrocarbons and optionally a part of the methane to carbon oxides and water, chilled to condense the water in the remaining gas stream without formation of hydrates, liquefied for ease of handling and storage and finally stripped to remove residual contaminants such as methane, carbon monoxide and nitrogen to produce the final food grade carbon dioxide product

  10. Effect of Elevated Carbon Dioxide Concentration on Carbon Assimilation under Fluctuating Light

    Czech Academy of Sciences Publication Activity Database

    Holišová, Petra; Zitová, Martina; Klem, Karel; Urban, Otmar

    2012-01-01

    Roč. 41, č. 6 (2012), s. 1931-1938 ISSN 0047-2425 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073; GA ČR(CZ) GAP501/10/0340; GA MŠk(CZ) LM2010007; GA AV ČR IAA600870701 Institutional support: RVO:67179843 Keywords : carbon * light * beech * spruce * carbon assimilation * elevat e carbon * dioxide concentration * mol * photosynthetic * assimilation * carbon dioxide * dioxide * concentracion * leave * photosynthetic efficiency Subject RIV: EH - Ecology, Behaviour Impact factor: 2.353, year: 2012

  11. BOREAS TGB-12 Isotropic Carbon Dioxide Data over the NSA

    Science.gov (United States)

    Trumbore, Susan; Hall, Forrest G. (Editor); Sundquist, Eric; Winston, Greg; Conrad, Sara K. (Editor)

    2000-01-01

    The BOREAS TGB-12 team made measurements of soil carbon inventories, carbon concentration in soil gases, and rates of soil respiration at several sites to estimate the rates of carbon accumulation and turnover in each of the major vegetation types. This data set contains information on the carbon isotopic content of carbon dioxide sampled from soils in the NSA-OBS, NSA-YJP, and NSA-OJP sites. Data were collected from 14-Nov-1993 to 10-Oct-1996. The data are stored in tabular ASCII files.

  12. Analytical study on carbon dioxide reforming of natural gas

    International Nuclear Information System (INIS)

    Ohashi, Hirofumi; Sakaki, Akihiro; Inagaki, Yoshiyuki

    2001-01-01

    In recent years, considerable attention has been paid to carbon dioxide reforming of natural gas, namely CO 2 reforming, since it can produce synthesis gas with low hydrogen-to-carbon ratio preferentially used for production of liquid hydrocarbons in the Fischer-Tropsch and methanol syntheses. This reaction has also very important environmental implications because CO 2 , a green house gas, may be converted into valuable feedstock. In JAERI, CO 2 reforming using the out-of-pile test facility, which is a 1/30 scale model of the HTTR hydrogen production system, is also being considered as an application of steam reforming. For the purpose to estimate the reformer performance in the facility, numerical analysis of natural gas reforming processes of CO 2 and combined reactions with steam and CO 2 has been carried out using mathematical model on heat and mass balance accompanied by chemical reactions. The reformer performance was evaluated in the effect of pressure, temperature, process gas composition and reaction rate constants of the catalyst on conversion, product gas composition and heat consumption of He gas. And also, the potential of carbon formation by CH 4 cracking reaction and Boudouard reaction was estimated. (author)

  13. Interaction of carbon dioxide with Cu overlayers on Pt(111)

    DEFF Research Database (Denmark)

    Schumacher, N.; Andersson, Klas Jerker; Grabow, L.C.

    2008-01-01

    Experimental and theoretical studies on the interaction of carbon dioxide with pseudomorphic and rough copper layers deposited on a platinum (111) single crystal are reported. Evidence for carbon dioxide dissociation and carbonate formation is presented and the relevance to methanol synthesis......) reveals a broad high temperature desorption state for CO2 with peak maximum around 450 K. X-ray photoelectron spectroscopy (XPS) shows that approximately one third of the oxygen accumulated on the surface upon CO2 exposure remains after TPD, indicative of carbonate formation via CO2 dissociation supplying...... O-ads and then facile CO2 + O-ads association, as well as subsequent decomposition at higher temperatures. Density functional theory studies of stepped Cu and Cu/Pt slabs reproduce vibrational frequencies of the carbonate, suggesting a nearly flat tridentate configuration at steps/defect sites....

  14. Kinetic study of coals gasification into carbon dioxide atmosphere

    Directory of Open Access Journals (Sweden)

    Korotkikh A.G.

    2015-01-01

    Full Text Available The solid fuel gasification process was investigated to define chemical reactions rate and activation energy for a gas-generator designing and regime optimizing. An experimental procedure includes coal char samples of Kuznetskiy and Kansko-Achinskiy deposits consequent argon pyrolysis into argon and oxidating into carbon dioxide with different temperatures. The thermogravimetric analysis data of coal char gasification into carbon dioxide was obtained in the temperature range 900–1200 ºC. The mass loss and gasification time dependencies from temperature were defined to calculate chemical reaction frequency factor and activation energy. Two coal char gasification physico-mathematical models were proposed and recommendations for them were formed.

  15. NOVEL CERAMIC MEMBRANE FOR HIGH TEMPERATURE CARBON DIOXIDE SEPARATION; SEMIANNUAL

    International Nuclear Information System (INIS)

    Jerry Y.S. Lin; Jun-ichi Ida

    2001-01-01

    This project is aimed at demonstrating technical feasibility for a lithium zirconate based dense ceramic membrane for separation of carbon dioxide from flue gas at high temperature. The research work conducted in this reporting period was focused on several fundamental issues of lithium zirconate important to the development of the dense inorganic membrane. These fundamental issues include material synthesis of lithium zirconate, phases and microstructure of lithium zirconate and structure change of lithium zirconate during sorption/desorption process. The results show difficulty to prepare the dense ceramic membrane from pure lithium zirconate, but indicate a possibility to prepare the dense inorganic membrane for carbon dioxide separation from a composite lithium zirconate

  16. Historic and projected vehicle use and carbon dioxide emissions

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    Data are presented in this chapter that show a decline in total carbon dioxide emissions per vehicle of about 20 between 1970 and 1987. However, it is also shown that the fuel economy gains of the 1970s and early 1980s in many countries have begun to erode. In the US, low fuel prices combined with a failure to strengthen fuel efficiency standards have led to recent declines in new-car fuel efficiency. Even if these trends are reversed carbon dioxide in the transport sector will not be reduced if over all motor vehicle use continues along present lines

  17. Visual and reversible carbon dioxide sensing enabled by doctor blade coated macroporous photonic crystals.

    Science.gov (United States)

    Lin, Yi-Han; Suen, Shing-Yi; Yang, Hongta

    2017-11-15

    With significant impacts of carbon dioxide on global climate change, carbon dioxide sensing is of great importance. However, most of the existing sensing technologies are prone to interferences from carbon monoxide, or suffer from the use of sophisticated instruments. This research reports the development of reproducible carbon dioxide sensor using roll-to-roll compatible doctor blade coated three-dimensional macroporous photonic crystals. The pores are functionalized with amine groups to allow the reaction with carbon dioxide in the presence of humidity. The adsorption of carbon dioxide leads to red-shift and amplitude reduction of the optical stop bands, resulting in carbon dioxide detection with visible readout. The dependences of the diffraction wavelength on carbon dioxide partial pressure for various amine-functionalized photonic crystals and different humidities in the environment are systematically investigated. In addition, the reproducibility of carbon dioxide sensing has also been demonstrated in this research. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Plant growth and physiology of vegetable plants as influenced by carbon dioxide environment

    International Nuclear Information System (INIS)

    Ito, Tadashi

    1973-01-01

    In order to obtain basic knowledge on the increased giving of carbon dioxide to vegetables, the carbon dioxide environment in growing houses was analyzed, and the physiological and ecological properties of vegetables cultivated in carbon dioxide environment were elucidated. To improve the carbon dioxide environment, giving increased quantity of carbon dioxide, air flow, ventilation, and others were examined. The concentration of carbon dioxide began to decrease when the illumination intensity on growing layer reached 1 -- 1.5 lux, owing to the photo-synthetic activity of vegetables, and decreased rapidly at 3 -- 5 lux. The lowering of carbon dioxide concentration lowered the photo-synthesis of vegetables extremely, and the transfer of synthesized carbohydrate to roots was obstructed. The effect suffered in low carbon dioxide concentration left some aftereffect even after ventilation and the recovery of carbon dioxide concentration. But this aftereffect was not observed in case of cucumber. To improve carbon dioxide environment, the air flow or ventilation required for minimizing the concentration lowering was determined, but giving increased quantity of carbon dioxide was most effective. The interaction of carbon dioxide concentration and light was examined regarding the effect on photo-synthesis, and some knowledge of practical application was obtained. The effect of giving more carbon dioxide was more remarkable as the treatment was given to younger seedlings and in the period when the capacity of absorbing assimilation products was higher. (Kako, I.)

  19. Reactivity of dolomite in water-saturated supercritical carbon dioxide: Significance for carbon capture and storage and for enhanced oil and gas recovery

    International Nuclear Information System (INIS)

    Wang Xiuyu; Alvarado, Vladimir; Swoboda-Colberg, Norbert; Kaszuba, John P.

    2013-01-01

    Highlights: ► Dolomite reactivity with wet and dry supercritical CO 2 were evaluated. ► Dolomite does not react with dry CO 2 . ► H 2 O-saturated supercritical CO 2 dissolves dolomite and precipitates carbonate mineral. ► Temperature/reaction time control morphology and extent of carbonate mineralization. ► Reaction with wet CO 2 may impact trapping, caprock integrity, and CCS/EOR injectivity. - Abstract: Carbon dioxide injection in porous reservoirs is the basis for carbon capture and storage, enhanced oil and gas recovery. Injected carbon dioxide is stored at multiple scales in porous media, from the pore-level as a residual phase to large scales as macroscopic accumulations by the injection site, under the caprock and at reservoir internal capillary pressure barriers. These carbon dioxide saturation zones create regions across which the full spectrum of mutual CO 2 –H 2 O solubility may occur. Most studies assume that geochemical reaction is restricted to rocks and carbon dioxide-saturated formation waters, but this paradigm ignores injection of anhydrous carbon dioxide against brine and water-alternating-gas flooding for enhanced oil recovery. A series of laboratory experiments was performed to evaluate the reactivity of the common reservoir mineral dolomite with water-saturated supercritical carbon dioxide. Experiments were conducted at reservoir conditions (55 and 110 °C, 25 MPa) and elevated temperature (220 °C, 25 MPa) for approximately 96 and 164 h (4 and 7 days). Dolomite dissolves and new carbonate mineral precipitates by reaction with water-saturated supercritical carbon dioxide. Dolomite does not react with anhydrous supercritical carbon dioxide. Temperature and reaction time control the composition, morphology, and extent of formation of new carbonate minerals. Mineral dissolution and re-precipitation due to reaction with water-saturated carbon dioxide may affect the contact line between phases, the carbon dioxide contact angle, and the

  20. Ultrapulse carbon dioxide laser ablation of xanthelasma palpebrarum: A case series

    Directory of Open Access Journals (Sweden)

    Vikas Pathania

    2015-01-01

    Full Text Available Context: Xanthelasma palpebrarum is the most common form of xanthomas. Albeit a benign entity, it is cosmetically disturbing and a frequently recurring dermatologic referral. Although the classical treatment option remains surgical excision, alternatively, chemical cauterization, cryosurgery and electrofulguration have all been tried in the past with mixed results. The use of laser systems such as carbon dioxide laser, Erb:YAG laser, Q-switched Nd:YAG laser, diode laser, pulsed dye laser and KTP laser have become popular in the treatment of these lesions. Recent literature suggests minimal pigmentary changes and scarring with the use of ultrapulse carbon dioxide laser treatment of these lesions. Aim: To study and evaluate the effectiveness of ultrapulse carbon dioxide laser ablation for treatment of xanthelasma palpebrarum. Materials and Methods: 10 patients presenting with bilateral xanthelasma palpebrarum, new and with recurrence were studied for results after a single treatment with ultrapulse carbon dioxide laser (10,600 nm; 100-200 Hz; 200-400 μsec. The follow-up time was 9 months. Results: All lesions were treatable with a single-laser treatment session. Two patients (20% developed recurrence during the follow-up period. Side effects included post inflammatory hyperpigmentation in two patients (20%, but no visible scarring was observed. Conclusions: The ultrapulse carbon dioxide laser is an effective and safe therapeutic alternative in treatment of xanthelasma palpebrarum.

  1. Industrial structural transformation and carbon dioxide emissions in China

    International Nuclear Information System (INIS)

    Zhou, Xiaoyan; Zhang, Jie; Li, Junpeng

    2013-01-01

    Using provincial panel data from the period 1995–2009 to analyze the relationship between the industrial structural transformation and carbon dioxide emissions in China, we find that the first-order lag of industrial structural adjustment effectively reduced the emissions; technical progress itself did not reduce the emissions, but indirectly led to decreasing emissions through the upgrading and optimization of industrial structure. Foreign direct investment and intervention by local governments reduced carbon dioxide emissions, but urbanization significantly increased the emissions. Thus, industrial structural adjustment is an important component of the development of a low-carbon economy. In the context of industrial structural transformation, an effective way to reduce a region’s carbon dioxide emissions is to promote the upgrading and optimization of industrial structure through technical progress. Tighter environmental access policies, selective utilization of foreign direct investment, and improvements in energy efficiency can help to reduce carbon dioxide emissions. - Highlights: ► Relationship between the transformation of industrial structure and CO 2 emissions in China. ► Dynamic panel data model. ► Industrial structural adjustments can effectively reduce current CO 2 emissions. ► Technical progress leads to decreasing CO 2 emissions through upgrading of industrial structure

  2. Carbon Dioxide Effects Research and Assessment Program: Proceedings of the carbon dioxide and climate research program conference

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, L E [ed.

    1980-12-01

    Papers presented at the Carbon Dioxide and Climate Research Program Conference are included in this volume. Topics discussed are: the carbon cycle; modeling the carbon system; climatic response due to increased CO2; climate modeling; the use of paleoclimatic data in understanding climate change; attitudes and implications of CO2; social responses to the CO2 problem; a scenario for atmospheric CO2 to 2025; marine photosynthesis and the global carbon cycle; and the role of tropical forests in the carbon balance of the world. Separate abstracts of nine papers have been prepared for inclusion in the Energy Data Base. (RJC)

  3. Spatially explicit simulation of peatland hydrology and carbon dioxide exchange

    International Nuclear Information System (INIS)

    Sonnentag, O.

    2008-01-01

    A recent version of the Boreal Ecosystem Productivity Simulator (BEPS) was extended and modified to include northern peatlands. This thesis evaluated the BEPS-TerrainLab using observations made at the Mer Bleue bog located near Ottawa, Ontario, and the Sandhill fen located near Prince Albert, Saskatchewan. The code was revised to represent the multi-layer canopy and processes related to energy, water vapour and carbon dioxide fluxes through remotely-sensed leaf area index (LAI) maps. A quick and reliable method was also developed to determine shrub LAI with the LAI-2000 plant canopy analyzer. A large number of LAI data was collected at the Mer Bleue bog for the development of a new remote sensing-based methodology using multiple end member spectral unmixing to allow for separate tree and shrub LAI mapping in ombrotrophic peatlands. The methodology was also adapted for use in minerotrophic peatlands and their surrounding landscapes. These LAI maps within the BEPS-TerrainLab represented the tree and shrub layers of the Mer Bleue bog and the tree and shrub/sedge layers of the Sandhill fen. The study examined the influence of mesoscale topography (Mer Bleue bog) and macro- and mesoscale topography (Sandhill fen) on wetness, evapotranspiration, and gross primary productivity during the snow-free period of 2004. The results suggested that a peatland type-specific differentiation of macro- and mesoscale topographic effects on hydrology should be included in future peatland ecosystem modelling efforts in order to allow for a more realistic simulation of the soil water balance in peatlands and to reduce uncertainties in carbon dioxide and methane annual fluxes from wetlands

  4. Spatially explicit simulation of peatland hydrology and carbon dioxide exchange

    Energy Technology Data Exchange (ETDEWEB)

    Sonnentag, O.

    2008-08-01

    A recent version of the Boreal Ecosystem Productivity Simulator (BEPS) was extended and modified to include northern peatlands. This thesis evaluated the BEPS-TerrainLab using observations made at the Mer Bleue bog located near Ottawa, Ontario, and the Sandhill fen located near Prince Albert, Saskatchewan. The code was revised to represent the multi-layer canopy and processes related to energy, water vapour and carbon dioxide fluxes through remotely-sensed leaf area index (LAI) maps. A quick and reliable method was also developed to determine shrub LAI with the LAI-2000 plant canopy analyzer. A large number of LAI data was collected at the Mer Bleue bog for the development of a new remote sensing-based methodology using multiple end member spectral unmixing to allow for separate tree and shrub LAI mapping in ombrotrophic peatlands. The methodology was also adapted for use in minerotrophic peatlands and their surrounding landscapes. These LAI maps within the BEPS-TerrainLab represented the tree and shrub layers of the Mer Bleue bog and the tree and shrub/sedge layers of the Sandhill fen. The study examined the influence of mesoscale topography (Mer Bleue bog) and macro- and mesoscale topography (Sandhill fen) on wetness, evapotranspiration, and gross primary productivity during the snow-free period of 2004. The results suggested that a peatland type-specific differentiation of macro- and mesoscale topographic effects on hydrology should be included in future peatland ecosystem modelling efforts in order to allow for a more realistic simulation of the soil water balance in peatlands and to reduce uncertainties in carbon dioxide and methane annual fluxes from wetlands.

  5. Classroom Demonstration: Combustion of Diamond to Carbon Dioxide Followed by Reduction to Graphite

    Science.gov (United States)

    Miyauchi, Takuya; Kamata, Masahiro

    2012-01-01

    An educational demonstration shows the combustion of carbon to carbon dioxide and then the reduction of carbon dioxide to carbon. A melee diamond is the source of the carbon and the reaction is carried out in a closed flask. The demonstration helps students to realize that diamonds are made of carbon and that atoms do not change or vanish in…

  6. Reaction mechanisms for enhancing carbon dioxide mineral sequestration

    Science.gov (United States)

    Jarvis, Karalee Ann

    Increasing global temperature resulting from the increased release of carbon dioxide into the atmosphere is one of the greatest problems facing society. Nevertheless, coal plants remain the largest source of electrical energy and carbon dioxide gas. For this reason, researchers are searching for methods to reduce carbon dioxide emissions into the atmosphere from the combustion of coal. Mineral sequestration of carbon dioxide reacted in electrolyte solutions at 185°C and 2200 psi with olivine (magnesium silicate) has been shown to produce environmentally benign carbonates. However, to make this method feasible for industrial applications, the reaction rate needs to be increased. Two methods were employed to increase the rate of mineral sequestration: reactant composition and concentration were altered independently in various runs. The products were analyzed with complete combustion for total carbon content. Crystalline phases in the product were analyzed with Debye-Scherrer X-ray powder diffraction. To understand the reaction mechanism, single crystals of San Carlos Olivine were reacted in two solutions: (0.64 M NaHCO3/1 M NaCl) and (5.5 M KHCO3) and analyzed with scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron energy loss spectroscopy (EELS), and fluctuation electron microscopy (FEM) to study the surface morphology, atomic crystalline structure, composition and amorphous structure. From solution chemistry studies, it was found that increasing the activity of the bicarbonate ion increased the conversion rate of carbon dioxide to magnesite. The fastest conversion, 60% conversion in one hour, occurred in a solution of 5.5 M KHCO3. The reaction product particles, magnesium carbonate, significantly increased in both number density and size on the coupon when the bicarbonate ion activity was increased. During some experiments reaction vessel corrosion also altered the mineral sequestration mechanism. Nickel ions from vessel

  7. Sources and delivery of carbon dioxide for enhanced oil recovery. Final report, October 1977--December 1978

    Energy Technology Data Exchange (ETDEWEB)

    Hare, M.; Perlich, H.; Robinson, R.; Shah, M.; Zimmerman, F.

    1978-12-01

    Results are presented from a comprehensive study by Pullman Kellogg, with assistance from Gulf Universities Research Consortium (GURC) and National Cryo-Chemics Incorporated (NCI), of the carbon dioxide supply situation for miscible flooding operations to enhance oil recovery. A survey of carbon dioxide sources within the geographic areas of potential EOR are shown on four regional maps with the tabular data for each region to describe the sources in terms of quantity and quality. Evaluation of all the costs, such as purchase, production, processing, and transportation, associated with delivering the carbon dioxide from its source to its destination are presented. Specific cases to illustrate the use of the maps and cost charts generated in this study have been examined.

  8. Energy Saving High-Capacity Moderate Pressure Carbon Dioxide Storage System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Our approach to high-pressure carbon dioxide storage will directly address the challenges associated with storage of compressed carbon dioxide - the need to reduce...

  9. Light-Duty Automotive Technology, Carbon Dioxide Emissions, and Fuel Economy Trends Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Light-Duty Automotive Technology, Carbon Dioxide Emissions, and Fuel Economy Trends report is the authoritative reference for carbon dioxide (CO2) emissions,...

  10. Carbon dioxide and methane dynamics in estuaries

    Science.gov (United States)

    Borges, Alberto V.; Abril, Gwenaël.

    2010-05-01

    We carried out a literature overview to synthesize current knowledge on CO2 and CH4 dynamics and fluxes with the atmosphere in estuarine environments. Estuarine systems are highly dynamic in terms of carbon cycling and emit CO2 to the atmosphere at rates that are quantitatively significant for the global C cycle. This emission of CO2 to the atmosphere is strongly supported by the net heterotrophic nature of these ecosystems. The robustness of the evaluation of the emission of CO2 from estuarine ecosystems has increased in last years due to increasing data availability and improvements in the surface area estimates by types. At present, the lack of sufficient data is the major limitation in the quantification of the spatial and temporal variability of CO2 fluxes in estuarine environments. Regarding future observations, there is also a need for sustained measurements to unravel inter-annual variability and long-term trends of CO2 and CH4 in estuarine environments. Indeed, due to the strong linkage with river catchements, inter-annual variability of CO2 and CH4 in estuarine environments is expected to be strong. Data used in the present synthesis were either obtained by the authors, data mined from publications or communicated by colleagues. There is a need for publicly available and quality checked data-bases for CO2 and CH4 in estuarine environments. Not only cross-system meta-analysis of data (CO2, CH4, O2, …) can be enlightening as explored in the present work, but also considering the uncertainties in the evaluation of the gas transfer velocity, there could be a need for future re-evaluations of air-water CO2 and CH4 fluxes, requiring access to the raw pCO2 and [CH4] data.

  11. Carbon dioxide sequestration by aqueous mineral carbonation of magnesium silicate minerals

    Energy Technology Data Exchange (ETDEWEB)

    Gerdemann, Stephen J.; Dahlin, David C.; O' Connor, William K.; Penner, Larry R.

    2003-01-01

    The dramatic increase in atmospheric carbon dioxide since the Industrial Revolution has caused concerns about global warming. Fossil-fuel-fired power plants contribute approximately one third of the total human-caused emissions of carbon dioxide. Increased efficiency of these power plants will have a large impact on carbon dioxide emissions, but additional measures will be needed to slow or stop the projected increase in the concentration of atmospheric carbon dioxide. By accelerating the naturally occurring carbonation of magnesium silicate minerals it is possible to sequester carbon dioxide in the geologically stable mineral magnesite (MgCO3). The carbonation of two classes of magnesium silicate minerals, olivine (Mg2SiO4) and serpentine (Mg3Si2O5(OH)4), was investigated in an aqueous process. The slow natural geologic process that converts both of these minerals to magnesite can be accelerated by increasing the surface area, increasing the activity of carbon dioxide in the solution, introducing imperfections into the crystal lattice by high-energy attrition grinding, and in the case of serpentine, by thermally activating the mineral by removing the chemically bound water. The effect of temperature is complex because it affects both the solubility of carbon dioxide and the rate of mineral dissolution in opposing fashions. Thus an optimum temperature for carbonation of olivine is approximately 185 degrees C and 155 degrees C for serpentine. This paper will elucidate the interaction of these variables and use kinetic studies to propose a process for the sequestration of the carbon dioxide.

  12. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    Energy Technology Data Exchange (ETDEWEB)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; Alejandro Lopez-Ortiz; Douglas P. Harrison; Ya Liang

    2001-05-01

    Electrobalance studies of calcination and carbonation of sodium bicarbonate materials were conducted at Louisiana State University. Calcination in an inert atmosphere was rapid and complete at 120 C. Carbonation was temperature dependent, and both the initial rate and the extent of reaction were found to decrease as temperature was increased between 60 and 80 C. A fluidization test apparatus was constructed at RTI and two sodium bicarbonate materials were fluidized in dry nitrogen at 22 C. The bed was completely fluidized at between 9 and 11 in. of water pressure drop. Kinetic rate expression derivations and thermodynamic calculations were conducted at RTI. Based on literature data, a simple reaction rate expression, which is zero order in carbon dioxide and water, was found to provide the best fit against reciprocal temperature. Simulations based on process thermodynamics suggested that approximately 26 percent of the carbon dioxide in flue gas could be recovered using waste heat available at 240 C.

  13. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    International Nuclear Information System (INIS)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; Alejandro Lopez-Ortiz; Douglas P. Harrison; Ya Liang

    2001-01-01

    Electrobalance studies of calcination and carbonation of sodium bicarbonate materials were conducted at Louisiana State University. Calcination in an inert atmosphere was rapid and complete at 120 C. Carbonation was temperature dependent, and both the initial rate and the extent of reaction were found to decrease as temperature was increased between 60 and 80 C. A fluidization test apparatus was constructed at RTI and two sodium bicarbonate materials were fluidized in dry nitrogen at 22 C. The bed was completely fluidized at between 9 and 11 in. of water pressure drop. Kinetic rate expression derivations and thermodynamic calculations were conducted at RTI. Based on literature data, a simple reaction rate expression, which is zero order in carbon dioxide and water, was found to provide the best fit against reciprocal temperature. Simulations based on process thermodynamics suggested that approximately 26 percent of the carbon dioxide in flue gas could be recovered using waste heat available at 240 C

  14. Somewhere beyond the sea? The oceanic - carbon dioxide - reactions

    Science.gov (United States)

    Meisinger, Philipp; Wittlich, Christian

    2014-05-01

    In correlation to climate change and CO2 emission different campaigns highlight the importance of forests and trees to regulate the concentration of carbon dioxide in the earths' atmosphere. Seeing millions of square miles of rainforest cut down every day, this is truly a valid point. Nevertheless, we often tend to forget what scientists like Spokes try to raise awareness for: The oceans - and foremost deep sea sections - resemble the second biggest deposit of carbon dioxide. Here carbon is mainly found in form of carbonate and hydrogen carbonate. The carbonates are needed by corals and other sea organisms to maintain their skeletal structure and thereby to remain vital. To raise awareness for the protection of this fragile ecosystem in schools is part of our approach. Awareness is achieved best through understanding. Therefore, our approach is a hands-on activity that aims at showing students how the carbon dioxide absorption changes in relation to the water temperature - in times of global warming a truly sensitive topic. The students use standard syringes filled with water (25 ml) at different temperatures (i.e. 10°C, 20°C, 40°C). Through a connector students inject carbon dioxide (25ml) into the different samples. After a fixed period of time, students can read of the remaining amount of carbon dioxide in relation to the given water temperature. Just as with every scientific project, students need to closely monitor their experiments and alter their setups (e.g. water temperature or acidity) according to their initial planning. A digital template (Excel-based) supports the analysis of students' experiments. Overview: What: hands-on, minds -on activity using standard syringes to exemplify carbon dioxide absorption in relation to the water temperature (Le Chatelier's principle) For whom: adjustable from German form 11-13 (age: 16-19 years) Time: depending on the prior knowledge 45-60 min. Sources (extract): Spokes, L.: Wie Ozeane CO2 aufnehmen. Environmental

  15. Social acceptance of carbon dioxide storage

    International Nuclear Information System (INIS)

    Huijts, Nicole M.A.; Midden, Cees J.H.; Meijnders, Anneloes L.

    2007-01-01

    This article discusses public acceptance of carbon capture and storage (CCS). Responses by citizens are described in relation to responses by professionally involved actors. Interviews with members of the government, industry and environmental NGOs showed that these professional actors are interested in starting up storage projects, based on thorough evaluation processes, including discussions on multi-actor working groups. As appeared from a survey among citizens living near a potential storage site (N=103), public attitudes in general were slightly positive, but attitudes towards storage nearby were slightly negative. The general public appeared to have little knowledge about CO 2 -storage, and have little desire for more information. Under these circumstances, trust in the professional actors is particularly important. NGOs were found to be trusted most, and industry least by the general public. Trust in each of the three actors appeared to depend on perceived competence and intentions, which in turn were found to be related to perceived similarity of goals and thinking between trustee and trustor. Implications for communication about CCS are discussed. (author)

  16. Measurements of carbon dioxide and heat fluxes during monsoon ...

    Indian Academy of Sciences (India)

    An increase in carbon dioxide (CO2) concentrations in the atmosphere due to ... The changes in land ... the air quality and climate models. 2. ... soon period of 2011 as a part Cloud Aerosol .... density effects due to heat and water vapour trans-.

  17. TWO-PHASE EJECTOR of CARBON DIOXIDE HEAT PUMP CALCULUS

    Directory of Open Access Journals (Sweden)

    Sit B.M.

    2010-12-01

    Full Text Available It is presented the calculus of the two-phase ejector for carbon dioxide heat pump. The method of calculus is based on the method elaborated by S.M. Kandil, W.E. Lear, S.A. Sherif, and is modified taking into account entrainment ratio as the input for the calculus.

  18. Convergence of carbon dioxide emissions in different sectors in China

    International Nuclear Information System (INIS)

    Wang, Juan; Zhang, Kezhong

    2014-01-01

    In this paper, we analyze differences in per capita carbon dioxide emissions from 1996 to 2010 in six sectors across 28 provinces in China and examine the σ-convergence, stochastic convergence and β-convergence of these emissions. We also investigate the factors that impact the convergence of per capita carbon dioxide emissions in each sector. The results show that per capita carbon dioxide emissions in all sectors converged across provinces from 1996 to 2010. Factors that impact the convergence of per capita carbon dioxide emissions in each sector vary: GDP (gross domestic product) per capita, industrialization process and population density impact convergence in the Industry sector, while GDP per capita and population density impact convergence in the Transportation, Storage, Postal, and Telecommunications Services sector. Aside from GDP per capita and population density, trade openness also impacts convergence in the Wholesale, Retail, Trade, and Catering Service sector. Population density is the only factor that impacts convergence in the Residential Consumption sector. - Highlights: • Analyze differences in CO 2 emissions in six sectors among 28 provinces in China. • Examine the convergence of CO 2 emissions in six sectors. • Investigate factors impact on convergence of CO 2 emissions in each sector. • Factors impact on convergence of per capita CO 2 emissions in each sector vary

  19. Carbon dioxide (CO 2 ) utilizing strain database | Saini | African ...

    African Journals Online (AJOL)

    Culling of excess carbon dioxide from our environment is one of the major challenges to scientific communities. Many physical, chemical and biological methods have been practiced to overcome this problem. The biological means of CO2 fixation using various microorganisms is gaining importance because database of ...

  20. Intravenous carbon dioxide as an echocardiographic contrast agent

    NARCIS (Netherlands)

    R.S. Meltzer (Richard); P.W.J.C. Serruys (Patrick); P.G. Hugenholtz (Paul); J.R.T.C. Roelandt (Jos)

    1981-01-01

    textabstractIntravenous carbon dioxide (CO2) was employed to cause echocardiographic contrast in 40 patients. One to 3 cc of medically pure CO2 were agitated with 5 to 8 cc of 5% dextrose in water and rapidly injected into an upper extremity vein. Contrast was obtained in all patients. In 33

  1. 2001-2002 carbon dioxide emissions in OECD

    International Nuclear Information System (INIS)

    2004-11-01

    This document provides carbon dioxide emissions data, from energy uses and production, from 2001 to 2002 in the OECD. It concerns the climate corrected CO 2 emissions in France, the non corrected CO 2 emissions (M tons), the emissions intensity / the Gross Domestic Product and the emissions intensity / the population (tons per inhabitant). (A.L.B.)

  2. Heliox Improves Carbon Dioxide Removal during Lung Protective Mechanical Ventilation

    NARCIS (Netherlands)

    Beurskens, Charlotte J.; Brevoord, Daniel; Lagrand, Wim K.; van den Bergh, Walter M.; Vroom, Margreeth B.; Preckel, Benedikt; Horn, Janneke; Juffermans, Nicole P.

    2014-01-01

    Introduction. Helium is a noble gas with low density and increased carbon dioxide (CO2) diffusion capacity. This allows lower driving pressures in mechanical ventilation and increased CO2 diffusion. We hypothesized that heliox facilitates ventilation in patients during lung-protective mechanical

  3. Cavitation-induced reactions in high-pressure carbon dioxide

    NARCIS (Netherlands)

    Kuijpers, M.W.A.; van Eck, D.; Kemmere, M.F.; Keurentjes, J.T.F.

    2002-01-01

    The feasibility of ultrasound-induced in situ radical formation in liquid carbon dioxide was demonstrated. The required threshold pressure for cavitation could be exceeded at a relatively low acoustic intensity, as the high vapor pressure of CO2 counteracts the hydrostatic pressure. With the use of

  4. Carbon dioxide angiography: a simple and safe system of delivery

    International Nuclear Information System (INIS)

    Cronin, P.; Patel, J.V.; Kessel, D.O.; Robertson, I.; McPherson, S.J.

    2005-01-01

    Carbon dioxide (CO 2 ) is an established alternate angiographic contrast agent, which can be delivered by pump or hand injection. We describe a simple, safe and inexpensive hand injection system that delivers a known volume of CO 2 at atmospheric pressure and prevents contamination with room air

  5. Intertidal zones as carbon dioxide sources to coastal oceans

    Digital Repository Service at National Institute of Oceanography (India)

    DileepKumar, M.; George, M.D.; Rajagopal, M.D.

    To understand the factors controlling carbon dioxide (CO sub(2)) exchanges near land-sea boundary diurnal observations have been made twice on CO sub(2) in the air and water in a coastal region. The results suggest that CO sub(2) enrichment...

  6. Extended-length fiber optic carbon dioxide monitoring

    Science.gov (United States)

    Delgado-Alonso, Jesus; Lieberman, Robert A.

    2013-05-01

    This paper discusses the design and performance of fiber optic distributed intrinsic sensors for dissolved carbon dioxide, based on the use optical fibers fabricated so that their entire lengths are chemically sensitive. These fibers use a polymer-clad, silica-core structure where the cladding undergoes a large, reversible, change in optical absorbance in the presence of CO2. The local "cladding loss" induced by this change is thus a direct indication of the carbon dioxide concentration in any section of the fiber. To create these fibers, have developed a carbon dioxide-permeable polymer material that adheres well to glass, is physically robust, has a refractive index lower than fused silica, and acts as excellent hosts for a unique colorimetric indicator system that respond to CO2. We have used this proprietary material to produce carbon-dioxide sensitive fibers up to 50 meters long, using commercial optical fiber fabrication techniques. The sensors have shown a measurement range of dissolved CO2 of 0 to 1,450 mg/l (0 to 100% CO2 saturation), limit of detection of 0.3 mg/l and precision of 1.0 mg/l in the 0 to 50 mg/l dissolved CO2 range, when a 5 meter-long sensor fiber segment is used. Maximum fiber length, minimum detectable concentration, and spatial resolution can be adjusted by adjusting indicator concentration and fiber design.

  7. Electrochemical carbon dioxide reduction on rough copper surfaces

    NARCIS (Netherlands)

    Kas, Recep

    2016-01-01

    Sustainable development and climate change is considered to be one of the top challenges of humanity. Electrochemical carbon dioxide (CO2) reduction to fuels or fuel precursor using renewable electricity is a very promising way to recycle CO2 and store the electricity. This would also provide

  8. Distribution of Carbon Dioxide Produced by People in a Room:

    DEFF Research Database (Denmark)

    Naydenov, Kiril Georgiev; Baránková, Petra; Sundell, Jan

    2004-01-01

    Carbon dioxide exhaled by people can be used as a tracer gas for air change measurements in homes. Good mixing of tracer gas with room air is a necessary condition to obtain accurate results. However, the use of fans to ensure mixing is inconvenient. The natural room distribution of metabolic CO2...

  9. The effect of carbon dioxide at high pressure under different ...

    African Journals Online (AJOL)

    user

    2011-03-14

    Mar 14, 2011 ... the pulse beetle, Callosobruchus maculates. J. Insect Sci. 9: 58-61. George NM, Sonny BR (1998). Comparative effect of short term exposures of Callosobruchus subinnotatus to carbon dioxide, nitrogen, or low temperature on behaviour and fecundity. Entomologia Experimentalis et Applicata Vol. 89, No.

  10. Integrated biofuel facility, with carbon dioxide consumption and power generation

    Energy Technology Data Exchange (ETDEWEB)

    Powell, E.E.; Hill, G.A. [Saskatchewan Univ., Saskatoon, SK (Canada). Dept. of Chemical Engineering

    2009-07-01

    This presentation provided details of an economical design for a large-scale integrated biofuel facility for coupled production of bioethanol and biodiesel, with carbon dioxide capture and power generation. Several designs were suggested for both batch and continuous culture operations, taking into account all costs and revenues associated with the complete plant integration. The microalgae species Chlorella vulgaris was cultivated in a novel photobioreactor (PBR) in order to consume industrial carbon dioxide (CO{sub 2}). This photosynthetic culture can also act as a biocathode in a microbial fuel cell (MFC), which when coupled to a typical yeast anodic half cell, results in a complete biological MFC. The photosynthetic MFC produces electricity as well as valuable biomass and by-products. The use of this novel photosynthetic microalgae cathodic half cell in an integrated biofuel facility was discussed. A series of novel PBRs for continuous operation can be integrated into a large-scale bioethanol facility, where the PBRs serve as cathodic half cells and are coupled to the existing yeast fermentation tanks which act as anodic half cells. These coupled MFCs generate electricity for use within the biofuel facility. The microalgae growth provides oil for biodiesel production, in addition to the bioethanol from the yeast fermentation. The photosynthetic cultivation in the cathodic PBR also requires carbon dioxide, resulting in consumption of carbon dioxide from bioethanol production. The paper also discussed the effect of plant design on net present worth and internal rate of return. tabs., figs.

  11. Dry-cleaning with high-pressure carbon dioxide

    NARCIS (Netherlands)

    Van Roosmalen, M.J.E.

    2003-01-01

    Dry-cleaning is a process for removing soils and stains from fabrics and garments which uses a non-aqueous solvent with detergent added. The currently most used dry-cleaning solvent is perchloroethylene (PER), which is toxic, environmentally harmful and suspected to be carcinogenic. Carbon dioxide

  12. Carbon dioxide hydrate formation in a fixed-bed reactor

    Energy Technology Data Exchange (ETDEWEB)

    Fan, S.; Lang, X. [South China Univ. of Technology, Guangzhou (China). Key Laboratory of Enhanced Heat Transfer and Energy Conservation; Wang, Y.; Liang, D. [Chinese Academy of Sciences, Guangzhou (China). Guangzhou Inst. of Energy Conversion and Guangzhou Center of Natural Gas Hydrate; Sun, X.; Jurcik, B. [Air Liquide Laboratories, Tsukuba (Japan)

    2008-07-01

    Gas hydrates are thermodynamically stable at high pressures and near the freezing temperature of pure water. Methane hydrates occur naturally in sediments in the deep oceans and permafrost regions and constitute an extensive hydrocarbon reservoir. Carbon dioxide (CO{sub 2}) hydrates are of interest as a medium for marine sequestration of anthropogenic carbon dioxide. Sequestering CO{sub 2} as hydrate has potential advantages over most methods proposed for marine CO{sub 2} sequestration. Because this technique requires a shallower depth of injection when compared with other ocean sequestration methods, the costs of CO{sub 2} hydrate sequestration may be lower. Many studies have successfully used different continuous reactor designs to produce CO{sub 2} hydrates in both laboratory and field settings. This paper discussed a study that involved the design and construction of a fixed-bed reactor for simulation of hydrate formation system. Water, river sands and carbon dioxide were used to simulate the seep kind of hydrate formation. Carbon dioxide gas was distributed as small bubbles to enter from the bottom of the fixed-bed reactor. The paper discussed the experimental data and presented a diagram of the gas hydrate reactor system. The morphology as well as the reaction characters of CO{sub 2} hydrate was presented in detail. The results were discussed in terms of experimental phenomena and hydrate formation rate. A mathematical model was proposed for describing the process. 17 refs., 7 figs.

  13. 46 CFR 169.565 - Fixed carbon dioxide system.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Fixed carbon dioxide system. 169.565 Section 169.565 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS... cylinder storage area must be properly ventilated and the temperature inside must not exceed 130 °F. (g...

  14. Permeation of supercritical carbon dioxide through polymeric hollow fiber membranes

    NARCIS (Netherlands)

    Patil, V.E.; Broeke, van den L.J.P.; Vercauteren, F.F.; Keurentjes, J.T.F.

    2006-01-01

    Permeation of carbon dioxide was measured for two types of composite polymeric hollow fiber membranes for feed pressures up to 18 MPa at a temp. of 313 K. support membrane. The membranes consist of a polyamide copolymer (IPC) layer or a poly(vinyl alc.) (PVA) layer on top of a polyethersulfone

  15. Kinetics of absorption of carbon dioxide in aqueous ammonia solutions

    NARCIS (Netherlands)

    Derks, P. W. J.; Versteeg, G. F.

    2009-01-01

    In the present work the absorption of carbon dioxide into aqueous ammonia solutions has been studied in a stirred cell reactor, at low temperatures and ammonia concentrations ranging from 0.1 to about 7 kmol m-3. The absorption experiments were carried out at conditions where the so-called pseudo

  16. Classroom Carbon Dioxide Concentration, School Attendance, and Educational Attainment

    Science.gov (United States)

    Gaihre, Santosh; Semple, Sean; Miller, Janice; Fielding, Shona; Turner, Steve

    2014-01-01

    Background: We tested the hypothesis that classroom carbon dioxide (CO[subscript 2]) concentration is inversely related to child school attendance and educational attainment. Methods: Concentrations of CO[subscript 2] were measured over a 3-5?day period in 60 naturally ventilated classrooms of primary school children in Scotland. Concentrations of…

  17. Carbon Dioxide Absorption in a Membrane Contactor with Color Change

    Science.gov (United States)

    Pantaleao, Ines; Portugal, Ana F.; Mendes, Adelio; Gabriel, Joaquim

    2010-01-01

    A pedagogical experiment is described to examine the physical absorption of gases, in this case carbon dioxide, in a hollow fiber membrane contactor (HFMC) where the absorption concentration profile can be followed by a color change. The HFMC is used to teach important concepts and can be used in interesting applications for students, such as…

  18. Carbon dioxide laser resurfacing of rhytides and photodamaged skin

    OpenAIRE

    Kelly, KM; Nelson, JS

    1998-01-01

    Carbon dioxide (CO 2 ) laser resurfacing has been used as a method to treat rhytides and photodamaged skin. This laser offers several advantages over previously utilised modalities but its use has several inherent risks. This article will review important aspects of CO 2 laser resurfacing including laser-skin interactions, patient selection, effective pre- and post-operative regimens and potential complications.

  19. Water vapour and carbon dioxide decrease nitric oxide readings

    NARCIS (Netherlands)

    vanderMark, TW; Kort, E; Meijer, RJ; Postma, DS; Koeter, GH

    Measurement of nitric oxide levels in exhaled ah-is commonly performed using a chemiluminescence detector. However, water vapour and carbon dioxide affect the chemiluminescence process, The influence of these gases at the concentrations present in exhaled air has not vet been studied. For this in

  20. Catalytic polymerization of olefins in supercritical carbon dioxide

    NARCIS (Netherlands)

    Kemmere, M.F.; Vries, de T.J.; Keurentjes, J.T.F.

    2004-01-01

    A novel process is being developed for the catalytic polymerization of olefins in supercritical carbon dioxide (sc CO2), for which potential applications will mainly be in the production of EPDM and other elastomers. For this purpose, the Brookhart catalyst has been tested for the homopolymerization

  1. Thermal Properties of Supercritical Carbon Dioxide by Monte Carlo Simulations

    Czech Academy of Sciences Publication Activity Database

    Colina, C. M.; Olivera-Fuentes, C. G.; Siperstein, F. R.; Lísal, Martin; Gubbins, K. E.

    2003-01-01

    Roč. 29, 6-7 (2003), s. 405-412 ISSN 0892-7022 R&D Projects: GA ČR GA203/02/0805 Grant - others:NSF(US) CHE-9876674291 Institutional research plan: CEZ:AV0Z4072921 Keywords : fluctuations * carbon dioxide * 2CLJQ Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 0.721, year: 2003

  2. SELECTIVE OXIDATION IN SUPERCRITICAL CARBON DIOXIDE USING CLEAN OXIDANTS

    Science.gov (United States)

    We have systematically investigated heterogeneous catalytic oxidation of different substrates in supercritical carbon dioxide (SC-CO2). Three types of catagysts: a metal complex, 0.5% platinum g-alumina and 0.5% palladium g-alumina were used at a pressure of 200 bar, temperatures...

  3. Solubilities of ferrocene and acetylferrocene in supercritical carbon dioxide

    DEFF Research Database (Denmark)

    Kazemi, Somayeh; Belandria, Veronica; Janssen, Nico

    2012-01-01

    In this work, the solubilities of ferrocene and acetylferrocene in supercritical carbon dioxide (scCO2) were measured using an analytical method in a quasi-flow apparatus. High-performance liquid chromatography was applied through an online sampling procedure to determine the concentration...

  4. Routing strategy including time and carbon dioxide emissions : effects on network performance

    NARCIS (Netherlands)

    Zhang, Fan; Chen, Y.; Goni Ros, B.; GAO, Jian; Knoop, V.L.

    2016-01-01

    Traffic congestion leads to delays and increased carbon dioxide (CO2) emissions. Traffic management measures such as providing information on environmental route costs have been proposed to mitigate congestion. Multi-criteria routing dynamic traffic assignment (MCR-DTA) models are needed to evaluate

  5. Efficient Hydroformylation in Dense Carbon Dioxide using Phosphorus Ligands without Perfluoroalkyl Substituents

    NARCIS (Netherlands)

    Koeken, Ard C.J.; Benes, Nieck Edwin; van den Broeke, Leo J.P.; Keurentjes, Jos T.F.

    2009-01-01

    Rhodium catalysts modified with triphenylphosphine, triphenyl phosphite, and tris(2,4-di-tert-butylphenyl) phosphite have been evaluated for their performance in the hydroformylation of 1-octene using carbon dioxide as the solvent. It is demonstrated that these catalysts are very efficient for the

  6. Rightsizing expectations for carbon dioxide removal towards ambitious climate goals

    Science.gov (United States)

    Mach, K. J.; Field, C. B.

    2017-12-01

    Proven approaches for reducing heat-trapping emissions are increasingly cost competitive and feasible at scale. Such approaches include renewable-energy technologies, energy efficiency, reduced deforestation, and abatement of industrial and agricultural emissions. Their pace of deployment, though, is far from sufficient to limit warming well below 2°C above preindustrial levels, the goal of the Paris Agreement. Against this backdrop, technologies for carbon removal are increasingly asserted as key to climate policy. Carbon dioxide removal (CDR), or negative emissions, technologies can compensate for ongoing emissions, helping keep ambitious warming limits in reach. The dramatic rise of CDR approaches in analysis and planning towards ambitious climate goals, however, has stirred up discomfort and debate. Focusing on rightsizing CDR expectations, this presentation will first briefly reflect on the status of the suite of CDR possibilities. The options include strategies grounded in improved ecosystem stewardship (e.g., reforestation and afforestation, conservation agriculture); strategies that are also biomass-based but with more engineering and more trade-offs (e.g., biochar additions to soils, bioenergy with carbon capture and storage); and engineered, nonbiological approaches (e.g., enhanced weathering, direct air capture). Second, the presentation will evaluate constraints surrounding CDR deployment at large scale and in peak-and-decline scenarios. These constraints involve, for example, unprecedented rates of land transformation in climate change mitigation pathways limiting warming to 2°C with high probability. They also entail the substantial, little studied risks of scenarios with temperatures peaking and then declining. Third, the presentation will review emerging lessons from CDR implementation to date, such as in legally enforceable forest-offset projects, along with near-term opportunities for catalyzing CDR, such as through low-cost opportunities for

  7. The thermodynamics of direct air capture of carbon dioxide

    International Nuclear Information System (INIS)

    Lackner, Klaus S.

    2013-01-01

    An analysis of thermodynamic constraints shows that the low concentration of carbon dioxide in ambient air does not pose stringent limits on air capture economics. The thermodynamic energy requirement is small even using an irreversible sorbent-based process. A comparison to flue gas scrubbing suggests that the additional energy requirement is small and can be supplied with low-cost energy. In general, the free energy expended in the regeneration of a sorbent will exceed the free energy of mixing, as absorption is usually not reversible. The irreversibility, which grows with the depth of scrubbing, tends to affect flue gas scrubbing more than air capture which can successfully operate while extracting only a small fraction of the carbon dioxide available in air. This is reflected in a significantly lower theoretical thermodynamic efficiency for a single stage flue gas scrubber than for an air capture device, but low carbon dioxide concentration in air still results in a larger energy demand for air capture. The energy required for capturing carbon dioxide from air could be delivered in various ways. I analyze a thermal swing and also a previously described moisture swing which is driven by the evaporation of water. While the total amount of heat supplied for sorbent regeneration in a thermal swing, in accordance with Carnot's principle, exceeds the total free energy requirement, the additional free energy required as one moves from flue gas scrubbing to air capture can be paid with an amount of additional low grade heat that equals the additional free energy requirement. Carnot's principle remains satisfied because the entire heat supplied, not just the additional amount, must be delivered at a slightly higher temperature. Whether the system is driven by water evaporation or by low grade heat, the cost of the thermodynamically-required energy can be as small as $1 to $2 per metric ton of carbon dioxide. Thermodynamics does not pose a practical constraint on the

  8. Gettering of carbon dioxide by erbium thin films

    International Nuclear Information System (INIS)

    Mehrhoff, T.K.

    1980-01-01

    The interaction of carbon dioxide and erbium thin films is characterized at 300 to 900 0 C and 5 x 10 -7 torr. Temperature ramp experiments with thin erbium films indicated a significant reaction above 300 0 C, preceded by desorption of water vapor, hydrogen and nitrogen and/or carbon monoxide from the film surface. The sticking coefficients were plotted as a function of Langmuirs of carbon dioxide exposure. Between 400 and 600 0 C, the length of the exposure was found to be more important than the temperature of the exposure in determining the sticking coefficient. Some evolution of carbon monoxide was noted particularly in the 400 to 500 0 C region. An 80% conversion of carbon dioxide to carbon monoxide was measured at 500 0 C. The film pumping speeds were compared with published vapor pressure data for erbium. This comparison indicated that a significant portion of the pumping action observed at temperatures of 800 0 C and above was due to evaporation of erbium metal

  9. Practical modeling approaches for geological storage of carbon dioxide.

    Science.gov (United States)

    Celia, Michael A; Nordbotten, Jan M

    2009-01-01

    The relentless increase of anthropogenic carbon dioxide emissions and the associated concerns about climate change have motivated new ideas about carbon-constrained energy production. One technological approach to control carbon dioxide emissions is carbon capture and storage, or CCS. The underlying idea of CCS is to capture the carbon before it emitted to the atmosphere and store it somewhere other than the atmosphere. Currently, the most attractive option for large-scale storage is in deep geological formations, including deep saline aquifers. Many physical and chemical processes can affect the fate of the injected CO2, with the overall mathematical description of the complete system becoming very complex. Our approach to the problem has been to reduce complexity as much as possible, so that we can focus on the few truly important questions about the injected CO2, most of which involve leakage out of the injection formation. Toward this end, we have established a set of simplifying assumptions that allow us to derive simplified models, which can be solved numerically or, for the most simplified cases, analytically. These simplified models allow calculation of solutions to large-scale injection and leakage problems in ways that traditional multicomponent multiphase simulators cannot. Such simplified models provide important tools for system analysis, screening calculations, and overall risk-assessment calculations. We believe this is a practical and important approach to model geological storage of carbon dioxide. It also serves as an example of how complex systems can be simplified while retaining the essential physics of the problem.

  10. Extraction of Carbon Dioxide and Hydrogen from Seawater and Hydrocarbon Production Therefrom

    Science.gov (United States)

    2016-04-05

    acidification of seawater by subjecting the seawater to an ion exchange reaction to exchange H.sup. ions for Na.sup. ions. Carbon dioxide may be...extracted from the acidified seawater. Optionally, the ion exchange reaction can be conducted under conditions which produce hydrogen as well as carbon dioxide . The carbon dioxide and hydrogen may be used to produce hydrocarbons.

  11. Carbon Dioxide (CO2) in Blood: MedlinePlus Lab Test Information

    Science.gov (United States)

    ... this page: https://medlineplus.gov/labtests/carbondioxideco2inblood.html Carbon Dioxide (CO2) in Blood To use the sharing features ... this page, please enable JavaScript. What is a Carbon Dioxide (CO2) Blood Test? Carbon dioxide (CO2) is an ...

  12. 75 FR 75059 - Mandatory Reporting of Greenhouse Gases: Injection and Geologic Sequestration of Carbon Dioxide

    Science.gov (United States)

    2010-12-01

    ... Greenhouse Gases: Injection and Geologic Sequestration of Carbon Dioxide; Final Rule #0;#0;Federal Register... Mandatory Reporting of Greenhouse Gases: Injection and Geologic Sequestration of Carbon Dioxide AGENCY... greenhouse gas monitoring and reporting from facilities that conduct geologic sequestration of carbon dioxide...

  13. 27 CFR 27.42a - Still wines containing carbon dioxide.

    Science.gov (United States)

    2010-04-01

    ... carbon dioxide. 27.42a Section 27.42a Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND... On Imported Distilled Spirits, Wines, and Beer Wines § 27.42a Still wines containing carbon dioxide. Still wines may contain not more than 0.392 gram of carbon dioxide per 100 milliliters of wine; except...

  14. Microporous metal-organic framework with potential for carbon dioxide capture at ambient conditions

    NARCIS (Netherlands)

    Xiang, S.C.; He, Y.; Zhang, Z.; Wu, H.; Zhou, W.; Krishna, R.; Chen, B.

    2012-01-01

    Carbon dioxide capture and separation are important industrial processes that allow the use of carbon dioxide for the production of a range of chemical products and materials, and to minimize the effects of carbon dioxide emission. Porous metal-organic frameworks are promising materials to achieve

  15. Carbon dioxide euthanasia in rats: Oxygen supplementation minimizes signs of agitation and asphyxia

    NARCIS (Netherlands)

    Coenen, A.M.L.; Drinkenburg, W.H.I.M.; Hoenderken, R.; Luijtelaar, E.L.J.M. van

    1995-01-01

    This paper records the effects of carbon dioxide when used for euthanasia, on behaviour, electrical brain activity and heart rate in rats. Four different methods were used. Animals were placed in a box (a) that was completely filled with carbon dioxide; (b) into which carbon dioxide was streamed at

  16. Methane and Carbon Dioxide Emissions from Different Composting Periods

    Directory of Open Access Journals (Sweden)

    Cheng-Hsiung Chang

    2009-01-01

    Full Text Available To investigate green house gas emissions from compost preparations, methane and carbon dioxide concentrations and emission rates at different accumulative times and composting periods were determined. While the accumulative time was less than 10 min with a closed acrylic chamber, meth ane and carbon dioxide emissions in creased slightly but with high fluntuation in the sampling e ror, and these values decreased significantly when the accumulative time was more than 20 min. During the 8 weeks of composting, the methane emission rate reaches its peak near the end of the second week and the carbon dioxide emission rate does the same near the end of third week. Meth ane and carbon dioxide emissions had high val ues at the first stage of com post ing and then de creased grad u ally for the ma tu rity of com post. Carbon dioxide emission (y was significantly related to temperature (x1, moisture content (x2, and total or ganiccarbon (x3; and there gression equation is: y = 3.11907x1 + 6.19236x2 - 6.63081x3 - 50.62498. The re gres sion equa tion be tween meth ane emis sion (y? and mois ture con tent (x2, pH (x4, C/N ra tio (x5, and ash con tent (x6 is: y?= 0.13225x2 - 0.97046x4 - 1.10599x5 - 0.55220x6 + 50.77057 in the ini tial com post ing stage (weeks 1 to 3; while, the equa tion is: y?= 0.02824x2 - 0.0037x4 - 0.1499x5 - 0.07013x6 + 4.13589 in the later compost ing stage (weeks 4 to 8. Dif ferent stage composts have significant variation of properties and greenhouse gas emissions. Moreover, the emissions may be reduced by manipulating the proper factors.

  17. urbanization and climate chang carbon dioxide emission

    African Journals Online (AJOL)

    userpc

    t efficient public urban mass transit that involves low carbon emissi individual car usage should be discouraged. ent, automobile density, climate change, global warming, greenhou e change .... Lagos, Port Harcourt, Abuja and Kano (Federal.

  18. Mineralization of Carbon Dioxide: Literature Review

    Energy Technology Data Exchange (ETDEWEB)

    Romanov, V; Soong, Y; Carney, C; Rush, G; Nielsen, B; O' Connor, W

    2015-01-01

    CCS research has been focused on CO2 storage in geologic formations, with many potential risks. An alternative to conventional geologic storage is carbon mineralization, where CO2 is reacted with metal cations to form carbonate minerals. Mineralization methods can be broadly divided into two categories: in situ and ex situ. In situ mineralization, or mineral trapping, is a component of underground geologic sequestration, in which a portion of the injected CO2 reacts with alkaline rock present in the target formation to form solid carbonate species. In ex situ mineralization, the carbonation reaction occurs above ground, within a separate reactor or industrial process. This literature review is meant to provide an update on the current status of research on CO2 mineralization. 2

  19. Synthesis of Chiral Cyclic Carbonates via Kinetic Resolution of Racemic Epoxides and Carbon Dioxide

    Directory of Open Access Journals (Sweden)

    Xiao Wu

    2016-01-01

    Full Text Available The catalytic synthesis of cyclic carbonates using carbon dioxide as a C1-building block is a highly active area of research. Here, we review the catalytic production of enantiomerically enriched cyclic carbonates via kinetic resolution of racemic epoxides catalysed by metal-containing catalyst systems.

  20. Past explosive outbursts of entrapped carbon dioxide in salt mines provide a new perspective on the hazards of carbon dioxide

    DEFF Research Database (Denmark)

    Hedlund, Frank Huess

    2013-01-01

    This paper reports on a source of past carbon dioxide accidents which so far has only been sporadically mentioned in the literature. Violent and highly destructive outbursts of hundreds of tons of CO2 occurred regularly, if not routinely, in the now closed salt mines of the former DDR. The Menzen...

  1. The carbon dioxide content in ice cores - climatic curves of carbon dioxide. Zu den CO sub 2 -Klimakurven aus Eisbohrkernen

    Energy Technology Data Exchange (ETDEWEB)

    Heyke, H.E.

    1992-05-01

    The 'greenhouse effect', which implies a temperature of 15 deg C as against -18 deg C, owes its effect to 80% from water (clouds and gaseous phase) and to 10% from carbon dioxide, besides other components. Whereas water is largely unaccounted for, carbon dioxide has been postulated as the main cause of anticipated climatic catastrophe. The carbon dioxide concentration in the atmosphere has risen presently to such levels that all previous figures seem to have been left far behind. The reference point is the concentration of carbon dioxide in the air bubbles trapped in ice cores of Antartic and Greenland ice dated 160 000 years ago, which show much lower values than at present. A review of the most relevant publications indicates that many basic laws of chemistry seem to have been left largely unconsidered and experimental errors have made the results rather doubtful. Appropriate arguments have been presented. The investigations considered should be repeated under improved and more careful conditions. (orig.).

  2. Do we need to sequester carbon dioxide?

    International Nuclear Information System (INIS)

    Delbecq, D.

    2011-01-01

    Carbon sequestration may be the solution to face our difficulty to cut down the use of fossil energies. CO 2 has to be separated from other gases released by thermal power plants before being stored in deep geological layers, there it can stay as a gas, or it can be dissolved in a fluid phase, or it can react with minerals and be integrated to a solid phase. Oil fields and deep saline water reservoirs are natural candidates for carbon sequestration. Carbon sequestration implies the installation of a network of pipelines to transport CO 2 from the place of production to the place of sequestration. The high cost of carbon sequestration implies the implementation of financial incentives from governments. Some economists foresee a raise of the electricity cost up to 50% if carbon sequestration is used. Other economists see a contradiction: sequestration techniques will not be available in a short term range while numerous thermal power plants are planned to be built in the decade. So carbon sequestration may arrive too late and at a cost that may be not competitive with some renewable energies like off-shore wind energy or thermal solar energy which will be full-grown at that time. (A.C.)

  3. Carbon dioxide effects research and assessment program

    International Nuclear Information System (INIS)

    Jacoby, G.

    1980-12-01

    Information about the past and present concentrations of CO 2 in the atmosphere and variations in climate can be obtained from measurements of stable isotopes in tree rings; specifically carbon-13, oxygen-18 and deuterium. The analysis of these stable isotopes in tree rings is a relatively new and rapidly developing field. This proceedings volume contains most of the papers presented at the meeting. The first paper gives an overview of the status of carbon-13 research. Papers relating to carbon-13 are in section I and grouped separately from the contributions on carbon-14. Although the meeting was primarily concerned with stable isotopes, all carbon isotopic analysis may be helpful in understanding the carbon-13 record in tree rings. The papers on hydrogen and oxygen isotope studies are in sections II and III respectively. The remaining sections contain papers that consider more than one isotope at a time, general topics related to isotopes, atmospheric changes and tree growth, and methods of isotopic analysis

  4. Fugitive carbon dioxide: It's not hiding in the ocean

    International Nuclear Information System (INIS)

    Kerr, R.A.

    1992-01-01

    The fugitive carbon is the difference between the 7 billion or so tons that spew as carbon dioxide from smokestacks and burning tropical forests and the 3.4 billion tons known to stay in the atmosphere. Finding the other 3 billion or 4 billion tons has frustrated researchers for the past 15 years. The oceans certainly take up some of it. Any forecast of global warming has to be based on how much of the carbon dioxide released by human activity will remain in the atmosphere, and predictions vary by 30% depending on the mix of oceanic and terrestrial processes assumed to be removing the gas. What's more, those predictions assume that the processes at work today will go on operating. But not knowing where all the carbon is going raises the unnerving possibility that whatever processes are removing it may soon fall down on the job without warning, accelerating any warming. Such concerns add urgency to the question of whether the ocean harbors the missing carbon. But there's no simple way to find out. The obvious strategy might seem to be to measure the carbon content of the ocean repeatedly to see how much it increases year by year. The trouble is that several billion tons of added carbon, though impressive on a human scale, are undetectable against the huge swings in ocean carbon that occur from season to season, year to year, and place to place

  5. Carbon dioxide elimination and regeneration of resources in a microwave plasma torch

    International Nuclear Information System (INIS)

    Uhm, Han S.; Kwak, Hyoung S.; Hong, Yong C.

    2016-01-01

    Carbon dioxide gas as a working gas produces a stable plasma-torch by making use of 2.45 GHz microwaves. The temperature of the torch flame is measured by making use of optical spectroscopy and a thermocouple device. Two distinctive regions are exhibited, a bright, whitish region of a high-temperature zone and a bluish, dimmer region of a relatively low-temperature zone. The bright, whitish region is a typical torch based on plasma species where an analytical investigation indicates dissociation of a substantial fraction of carbon dioxide molecules, forming carbon monoxides and oxygen atoms. The emission profiles of the oxygen atoms and the carbon monoxide molecules confirm the theoretical predictions of carbon dioxide disintegration in the torch. Various hydrocarbon materials may be introduced into the carbon dioxide torch, regenerating new resources and reducing carbon dioxide concentration in the torch. As an example, coal powders in the carbon dioxide torch are converted into carbon monoxide according to the reaction of CO_2 + C → 2CO, reducing a substantial amount of carbon dioxide concentration in the torch. In this regards, the microwave plasma torch may be one of the best ways of converting the carbon dioxides into useful new materials. - Highlights: • Carbon dioxide gas produces a plasma-torch by making use of 2.45 GHz microwaves. • The temperature measurement of torch flame by optical spectroscopy. • Disintegration of carbon dioxide into carbon monoxide and oxygen atom. • Emission profiles of carbon monoxide confirm disintegration theory. • Conversion of carbon dioxide into carbon monoxide in the plasma torch. - This article presents carbon-dioxide plasma torch operated by microwaves and its applications to regeneration of new resources, eliminating carbon dioxide molecules.

  6. Titanium dioxide modified with various amines used as sorbents of carbon dioxide

    International Nuclear Information System (INIS)

    Kapica-Kozar, Joanna; Pirog, Ewa; Kusiak-Nejman, Ewelina; Wrobel, Rafal J.; Gesikiewicz-Puchalska, Andzelika; Morawski, Antoni W.; Narkiewicz, Urszula; Michalkiewicz, Beata

    2017-01-01

    In this study, titanium dioxide was modified with various amines through hydrothermal treatment for adsorption of CO_2. The carbon dioxide adsorption performance of the prepared samples was measured using an STA 449 C thermo-balance (Netzsch Company, Germany). The morphological structures, functional groups and elemental compositions of the unmodified and amine-modified titanium dioxide sorbents were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR/DR) and scanning electron microscopy (SEM), respectively. The results showed that modification of TiO_2 with amines through hydrothermal treatment is a simple method to prepare CO_2 sorbents with high adsorption capacities. Moreover, the results revealed that TEPA-modified titanium dioxide shoved the highest adsorption capacity, enabling an increase in CO_2 uptake from 0.45 mmol CO_2 g"-"1 in the case of raw TiO_2 to 1.63 mmol CO_2 g"-"1. This result could be indirectly related to the fact that TEPA has the highest amino group content among the three amines used in our research. Additionally, durability tests performed by cyclic adsorption-desorption revealed that TEPA modified titanium dioxide also possesses excellent stability, despite a slight decrease in adsorption capacity over time. (authors)

  7. Production of precipitated calcium carbonate from calcium silicates and carbon dioxide

    International Nuclear Information System (INIS)

    Teir, Sebastian; Eloneva, Sanni; Zevenhoven, Ron

    2005-01-01

    The possibilities for reducing carbon dioxide emissions from the pulp and paper industry by calcium carbonation are presented. The current precipitated calcium carbonate (PCC) production uses mined, crushed calcium carbonate as raw materials. If calcium silicates were used instead, carbon dioxide emissions from the calcination of carbonates would be eliminated. In Finland, there could, thus, be a potential for eliminating 200 kt of carbon dioxide emissions per year, considering only the PCC used in the pulp and paper industry. A preliminary investigation of the feasibility to produce PCC from calcium silicates and the potential to replace calcium carbonate as the raw material was made. Calcium carbonate can be manufactured from calcium silicates by various methods, but only a few have been experimentally verified. The possibility and feasibility of these methods as a replacement for the current PCC production process was studied by thermodynamic equilibrium calculations using HSC software and process modelling using Aspen Plus[reg]. The results from the process modelling showed that a process that uses acetic acid for extraction of the calcium ions is a high potential option for sequestering carbon dioxide by mineral carbonation. The main obstacle seems to be the limited availability and relatively high price of wollastonite, which is a mineral with high calcium silicate content. An alternative is to use the more common, but also more complex, basalt rock instead

  8. Adsorption of water and carbon dioxide on hematite and consequences for possible hydrate formation.

    Science.gov (United States)

    Kvamme, Bjørn; Kuznetsova, Tatiana; Kivelae, Pilvi-Helina

    2012-04-07

    The interest in carbon dioxide for enhanced oil recovery is increasing proportional to the decline in naturally driven oil production and also due to the increasing demand for reduced emission of carbon dioxide into the atmosphere. Transport of carbon dioxide in offshore pipelines involves high pressure and low temperatures, conditions which may lead to formation of hydrates from residual water dissolved in carbon dioxide and carbon dioxide. The critical question is whether the water at certain temperatures and pressures will drop out as liquid droplets first, and then form hydrates, or alternatively, adsorb on the pipeline surfaces, and subsequently form hydrates heterogeneously. In this work, we used several different basis sets of density functional theory in ab initio calculations to estimate the charge distribution of hematite (the dominating component of rust) crystals. These rust particles were embedded in water and chemical potential for adsorbed water molecules was estimated through thermodynamic integration and compared to similar estimates for water clusters of the same size. While the generated charges were not unique, the use of high order approximations and different basis sets provides a range of likely charge distributions. Values obtained for the chemical potential of water in different surroundings indicated that it would be thermodynamically favorable for water to adsorb on hematite, and that evaluation of potential carbon dioxide hydrate formation conditions and kinetics should be based on this formation mechanism. Depending on the basis set and approximations, the estimated gain for water to adsorb on the hematite surface rather than condense as droplets varied between -1.7 kJ mole(-1) and -3.4 kJ mole(-1). The partial charge distribution on the hematite surface is incompatible with the hydrate structure, and thus hydrates will be unable to attach to the surface. The behavior of water outside the immediate vicinity of hematite (beyond 3

  9. Carbon dioxide (CO{sub 2}) digital subtraction angiography. Evaluation of a new delivery system; Angiografia con anidride carbonica. Nuovo sistema di iniezione

    Energy Technology Data Exchange (ETDEWEB)

    Nicolini, A.; Lovaria, A.; Meregaglia, D. [Ospedale Maggiore IRCCS Policlinico, Milan (Italy). Dipt. di Scienze Radiologiche; Palatresi, S. [Ospedale Maggiore IRCCS Policlinico, Milan (Italy). Ist. di Clinica Medica Generale e Terapia Medica

    2000-02-01

    Purpose of this work is to evaluate the usefulness of a new carbon dioxide (CO{sub 2}) intravascular injection system in digital subtraction angiography. March 1998 to May 1999, 39 patients were submitted to digital subtraction angiography with CO{sub 2} injection by a new delivery system, CO{sub 2}-Angio set, OptiMed, Ettingen, Germany. The patients were 29 men and 10 women, whose age ranged 32 to 76 (mean: 47), 18 of them with absolute or relative contraindications to iodinated contrast media and 6 with poor diagnostic findings at previous conventional angiography. CO{sub 2} was used for comparison with iodinated contrast agents in 4 patients. It was studied the following vascular districts: renal arteries in 9 patients, portal vein in 18, lower limb arteries in 7, upper limb veins in 4. In 1 patient CO{sub 2} angiography was carried out for the diagnosis and interventional treatment, by transcatheter embolization, of a postbioptic arteriovenous renal fistula. During the procedure, arterial blood pressure, EKG status and oxygen saturation were monitored, and subjective sensations recorded in all patients. CO{sub 2} angiography provided adequate visualization of vascular districts and of abnormal findings in 32 cased (82%), while its results were considered insufficient for correct and complete assessment in 7 cases (18%). CO{sub 2}-Angio set delivery system has proved to be a simple and safe tool, particularly suitable for use in patients at risk for allergic reactions to iodinated contrast agents and in those with renal function impairment. Also, the system can help carry out some interventional procedures such as arteriovenous fistula embolization and trans jugular portosystemic shunting. [Italian] Scopo di questo articolo e' verificare la validita' e l'efficacia di un nuovo sistema di iniezione angiografico per anidride carbonica. Da marzo 1998 a maggio 1999 sono stati sottoposti ad angiografia con anidride carbonica mediante sistema non

  10. Incentives of carbon dioxide regulation for investment in low-carbon electricity technologies in Texas

    International Nuclear Information System (INIS)

    Castillo, Anya; Linn, Joshua

    2011-01-01

    This paper compares the incentives a carbon dioxide emissions price creates for investment in low carbon dioxide-emitting technologies in the electricity sector. We consider the extent to which operational differences across generation technologies - particularly, nuclear, wind and solar photovoltaic - create differences in the incentives for new investment, which is measured by the operating profits of a potential entrant. First, astylized model of an electricity system demonstrates that the composition of the existing generation system may cause electricity prices to increase by different amounts over time when a carbon dioxide price is imposed. Differences in operation across technologies therefore translate to differences in the operating profits of a potential entrant. Then, a detailed simulation model is used to consider a hypothetical carbon dioxide price of $10-$50 per metric ton for the Electric Reliability Council of Texas (ERCOT) market. The simulations show that, for the range of prices considered, the increase in electricity prices is positively correlated with output from a typical wind unit, but the correlation is much weaker for nuclear and photovoltaic. Consequently, a carbon dioxide price creates much stronger investment incentives for wind than for nuclear or photovoltaic technologies in the Texas market. - Highlights: → Compare incentives for new investment in low-emission electricity technologies created by carbon dioxide price. → Focus on ERCOT power system using stochastic unit commitment model. →Find a greater incentive for wind than solar or nuclear because of correlation between wind generation and increase in electricity prices.

  11. Evaluation of the Addition liquor with high ammonia and Carbon Dioxide contentin the still 208 of the “Comandante Che Guevara” industry (ECG

    Directory of Open Access Journals (Sweden)

    María Elena Magaña-Haynes

    2015-12-01

    Full Text Available Adding fresh liquor through the 5th ring in still 208 of distilling liquor product (liquor obtained as a result of ammonium carbonate leaching of lateritic ore in the “Comandante Che Guevara” industry, were evaluated with the objective of reducing the dissolved nickel content of the effluent there from, as well as to improve the characteristics of the nickel carbonate which is delivered to the calcinations process. For the development of the survey, the same methodology used in 2001 for the test was applied. The results showed that by adding fresh liquor, it is possible to reduce the dissolved nickel content at the exit of the distillation column, so that the need for precipitation is minimized, thereby reducing the consumption of reagents and the and the cost for their acquisition. It was possible to corroborate the relationship between the content of NH3 at the discharge and the nickel dissolved therein appreciating that to achieve these results it is necessary to maintain the ammonia in the discharge between 1,0-1,8 g/L. The carbonate obtained in the column where liquor is added with high CO2 and NH3 reached high values of this last element in its composition and to the extent that increased sulphur content decreased. It was also seen an increase in the size of the coarse carbonates particles, which will influence in a decrease of energy consumption.

  12. Modelling carbon dioxide emissions from agricultural soils in Canada.

    Science.gov (United States)

    Yadav, Dhananjay; Wang, Junye

    2017-11-01

    Agricultural soils are a leading source of atmospheric greenhouse gas (GHG) emissions and are major contributors to global climate change. Carbon dioxide (CO 2 ) makes up 20% of the total GHG emitted from agricultural soil. Therefore, an evaluation of CO 2 emissions from agricultural soil is necessary in order to make mitigation strategies for environmental efficiency and economic planning possible. However, quantification of CO 2 emissions through experimental methods is constrained due to the large time and labour requirements for analysis. Therefore, a modelling approach is needed to achieve this objective. In this paper, the DeNitrification-DeComposition (DNDC), a process-based model, was modified to predict CO 2 emissions for Canada from regional conditions. The modified DNDC model was applied at three experimental sites in the province of Saskatchewan. The results indicate that the simulations of the modified DNDC model are in good agreement with observations. The agricultural management of fertilization and irrigation were evaluated using scenario analysis. The simulated total annual CO 2 flux changed on average by ±13% and ±1% following a ±50% variance of the total amount of N applied by fertilising and the total amount of water through irrigation applications, respectively. Therefore, careful management of irrigation and applications of fertiliser can help to reduce CO 2 emissions from the agricultural sector. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Carbon dioxide emissions from Indian monsoonal estuaries

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, V.V.S.S.; Viswanadham, R.; Rao, G.D.; Prasad, V.R.; Kumar, B.S.K.; Naidu, S.A.; Kumar, N.A.; Rao, D.B.; Sridevi, T.; Krishna, M.S.; Reddy, N.P.C.; Sadhuram, Y.; Murty, T.V.R.

    estuaries. The mean pCO sub(2) and particulate organic carbon (POC) showed positive relation with rate of discharge suggesting availability of high quantities of organic matter that led to enhanced microbial decomposition. The annual CO sub(2) fluxes from...

  14. Carbon dioxide adsorption in graphene sheets

    Directory of Open Access Journals (Sweden)

    Ashish Kumar Mishra

    2011-09-01

    Full Text Available Control over the CO2 emission via automobiles and industrial exhaust in atmosphere, is one of the major concerns to render environmental friendly milieu. Adsorption can be considered to be one of the more promising methods, offering potential energy savings compared to absorbent systems. Different carbon nanostructures (activated carbon and carbon nanotubes have attracted attention as CO2 adsorbents due to their unique surface morphology. In the present work, we have demonstrated the CO2 adsorption capacity of graphene, prepared via hydrogen induced exfoliation of graphitic oxide at moderate temperatures. The CO2 adsorption study was performed using high pressure Sieverts apparatus and capacity was calculated by gas equation using van der Waals corrections. Physical adsorption of CO2 molecules in graphene was confirmed by FTIR study. Synthesis of graphene sheets via hydrogen exfoliation is possible at large scale and lower cost and higher adsorption capacity of as prepared graphene compared to other carbon nanostructures suggests its possible use as CO2 adsorbent for industrial application. Maximum adsorption capacity of 21.6 mmole/g was observed at 11 bar pressure and room temperature (25 ºC.

  15. Carbon Dioxide Sealing Capacity: Textural or Compositional Controls?

    Energy Technology Data Exchange (ETDEWEB)

    Cranganu, Constantin; Soleymani, Hamidreza; Sadiqua, Soleymani; Watson, Kieva

    2013-11-30

    This research project is aiming to assess the carbon dioxide sealing capacity of most common seal-rocks, such as shales and non-fractured limestones, by analyzing the role of textural and compositional parameters of those rocks. We hypothesize that sealing capacity is controlled by textural and/or compositional pa-rameters of caprocks. In this research, we seek to evaluate the importance of textural and compositional parameters affecting the sealing capacity of caprocks. The conceptu-al framework involves two testable end-member hypotheses concerning the sealing ca-pacity of carbon dioxide reservoir caprocks. Better understanding of the elements controlling sealing quality will advance our knowledge regarding the sealing capacity of shales and carbonates. Due to relatively low permeability, shale and non-fractured carbonate units are considered relatively imper-meable formations which can retard reservoir fluid flow by forming high capillary pres-sure. Similarly, these unites can constitute reliable seals for carbon dioxide capture and sequestration purposes. This project is a part of the comprehensive project with the final aim of studying the caprock sealing properties and the relationship between microscopic and macroscopic characteristics of seal rocks in depleted gas fields of Oklahoma Pan-handle. Through this study we examined various seal rock characteristics to infer about their respective effects on sealing capacity in special case of replacing reservoir fluid with super critical carbon dioxide (scCO{sub 2}). To assess the effect of textural and compositional properties on scCO{sub 2} maximum reten-tion column height we collected 30 representative core samples in caprock formations in three counties (Cimarron, Texas, Beaver) in Oklahoma Panhandle. Core samples were collected from various seal formations (e.g., Cherokee, Keys, Morrowan) at different depths. We studied the compositional and textural properties of the core samples using several techniques

  16. COCAP: a carbon dioxide analyser for small unmanned aircraft systems

    Science.gov (United States)

    Kunz, Martin; Lavric, Jost V.; Gerbig, Christoph; Tans, Pieter; Neff, Don; Hummelgård, Christine; Martin, Hans; Rödjegård, Henrik; Wrenger, Burkhard; Heimann, Martin

    2018-03-01

    Unmanned aircraft systems (UASs) could provide a cost-effective way to close gaps in the observation of the carbon cycle, provided that small yet accurate analysers are available. We have developed a COmpact Carbon dioxide analyser for Airborne Platforms (COCAP). The accuracy of COCAP's carbon dioxide (CO2) measurements is ensured by calibration in an environmental chamber, regular calibration in the field and by chemical drying of sampled air. In addition, the package contains a lightweight thermal stabilisation system that reduces the influence of ambient temperature changes on the CO2 sensor by 2 orders of magnitude. During validation of COCAP's CO2 measurements in simulated and real flights we found a measurement error of 1.2 µmol mol-1 or better with no indication of bias. COCAP is a self-contained package that has proven well suited for the operation on board small UASs. Besides carbon dioxide dry air mole fraction it also measures air temperature, humidity and pressure. We describe the measurement system and our calibration strategy in detail to support others in tapping the potential of UASs for atmospheric trace gas measurements.

  17. Adsorption of Carbon Dioxide, Ammonia, Formaldehyde, and Water Vapor on Regenerable Carbon Sorbents

    Science.gov (United States)

    Wojtowicz, Marek A.; Cosgrove, Joseph E.; Serio, Michael A.; Wilburn, Monique

    2015-01-01

    Results are presented on the development of reversible sorbents for the combined carbon dioxide, moisture, and trace-contaminant (TC) removal for use in Extravehicular Activities (EVAs), and more specifically in the Primary Life Support System (PLSS). The currently available life support systems use separate units for carbon dioxide, trace contaminants, and moisture control, and the long-term objective is to replace the above three modules with a single one. Furthermore, the current TC-control technology involves the use of a packed bed of acid-impregnated granular charcoal, which is nonregenerable, and the carbon-based sorbent under development in this project can be regenerated by exposure to vacuum at room temperature. In this study, several carbon sorbents were fabricated and tested for simultaneous carbon dioxide, ammonia, formaldehyde, and water sorption. Multiple adsorption/vacuum-regeneration cycles were demonstrated at room temperature, and also the enhancement of formaldehyde sorption by the presence of ammonia in the gas mixture.

  18. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    Energy Technology Data Exchange (ETDEWEB)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; Douglas P. Harrison; Ya Liang

    2001-10-01

    The objective of this project is to develop a simple, inexpensive process to separate CO{sub 2} as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbent being used in this project is sodium carbonate which is converted to sodium bicarbonate, ''baking soda,'' through reaction with carbon dioxide and water vapor. Sodium bicarbonate is regenerated to sodium carbonate when heated, producing a nearly pure CO{sub 2} stream after condensation of water vapor. Testing conducted previously confirmed that the reaction rate and achievable CO{sub 2} capacity of sodium carbonate decreased with increasing temperature, and that the global rate of reaction of sodium carbonate to sodium bicarbonate increased with an increase in both CO{sub 2} and H{sub 2}O concentrations. Energy balance calculations indicated that the rate of heat removal from the particle surface may determine the reaction rate for a particular particle system. This quarter, thermogravimetric analyses (TGA) were conducted which indicated that calcination of sodium bicarbonate at temperatures as high as 200 C did not cause a significant decrease in activity in subsequent carbonation testing. When sodium bicarbonate was subjected to a five cycle calcination/carbonation test, activity declined slightly over the first two cycles but was constant thereafter. TGA tests were also conducted with two other potential sorbents. Potassium carbonate was found to be less active than sodium carbonate, at conditions of interest in preliminary TGA tests. Sodium carbonate monohydrate showed negligible activity. Testing was also conducted in a 2-inch internal diameter quartz fluidized-bed reactor system. A five cycle test demonstrated that initial removals of 10 to 15 percent of the carbon dioxide in a simulated flue gas could be achieved. The carbonation reaction proceeded at temperatures as low as 41 C. Future work by TGA and in fixed

  19. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    International Nuclear Information System (INIS)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; Douglas P. Harrison; Ya Liang

    2001-01-01

    The objective of this project is to develop a simple, inexpensive process to separate CO(sub 2) as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbent being used in this project is sodium carbonate which is converted to sodium bicarbonate, ''baking soda,'' through reaction with carbon dioxide and water vapor. Sodium bicarbonate is regenerated to sodium carbonate when heated, producing a nearly pure CO(sub 2) stream after condensation of water vapor. Testing conducted previously confirmed that the reaction rate and achievable CO(sub 2) capacity of sodium carbonate decreased with increasing temperature, and that the global rate of reaction of sodium carbonate to sodium bicarbonate increased with an increase in both CO(sub 2) and H(sub 2)O concentrations. Energy balance calculations indicated that the rate of heat removal from the particle surface may determine the reaction rate for a particular particle system. This quarter, thermogravimetric analyses (TGA) were conducted which indicated that calcination of sodium bicarbonate at temperatures as high as 200 C did not cause a significant decrease in activity in subsequent carbonation testing. When sodium bicarbonate was subjected to a five cycle calcination/carbonation test, activity declined slightly over the first two cycles but was constant thereafter. TGA tests were also conducted with two other potential sorbents. Potassium carbonate was found to be less active than sodium carbonate, at conditions of interest in preliminary TGA tests. Sodium carbonate monohydrate showed negligible activity. Testing was also conducted in a 2-inch internal diameter quartz fluidized-bed reactor system. A five cycle test demonstrated that initial removals of 10 to 15 percent of the carbon dioxide in a simulated flue gas could be achieved. The carbonation reaction proceeded at temperatures as low as 41 C. Future work by TGA and in fixed-bed, fluidized-bed, and transport

  20. Carbon dioxide management by chemical conversion to methanol: HYDROGENATION and BI-REFORMING

    International Nuclear Information System (INIS)

    Wiesberg, Igor L.; Medeiros, José Luiz de; Alves, Rita M.B.; Coutinho, Paulo L.A.; Araújo, Ofélia Q.F.

    2016-01-01

    Highlights: • Evaluation of carbon dioxide conversion to methanol by two chemical routes. • HYDROGENATION: conversion via catalytic hydrogenation at high pressure. • BI-REFORMING: conversion via syngas from bi-reforming of natural gas. • HYDROGENATION is viable for hydrogen price inferior to 1000 US$/t. • BI-REFORMING is unable to avoid emissions; viable only if gas price is very low. - Abstract: Chemical conversion of carbon dioxide to methanol has the potential to address two relevant sustainability issues: economically feasible replacement of fossil raw materials and avoidance of greenhouse gas emissions. However, chemical stability of carbon dioxide is a challenging impediment to conversion requiring severe reaction conditions at the expense of increased energy input, therefore adding capital, operation and environmental costs, which could result in partial or total override of its potential sustainability as feedstock to the chemical and energy industries. This work investigates two innovative chemical destinations of carbon dioxide to methanol, namely a direct conversion through carbon dioxide hydrogenation (HYDROGENATION), and an indirect via carbon dioxide conversion to syngas through bi-reforming (BI-REFORMING). Process simulation is used to obtain mass and energy balances needed to support assessment of economic and environmental performance. A business scenario is considered where an industrial source of nearly pure carbon dioxide exists and an investment decision for utilization of carbon dioxide is faced. Due to uncertainties in prices of the raw materials, hydrogen (HYDROGENATION) and natural gas (BI-REFORMING), the decision procedure includes the definition of price thresholds to reach profitability. Sensitivity analyses are performed varying costs with greater uncertainty, i.e., carbon dioxide and methanol, and recalculating maximum allowable prices of raw materials. The analyses show that in a Brazilian scenario, BI-REFORMING is unlikely

  1. Uranium tetracyclopentadienyl interaction with carbon oxide and dioxide

    International Nuclear Information System (INIS)

    Leonov, M.R.; Solov'eva, G.V.; Kozina, I.Z.; Bolotova, G.T.

    1983-01-01

    Using the methods of gas-liquid chromatography, IR and UV spectroscopy and element analysis, the reactions of tetracyclogentadienyluranium with carbon oxide and dioxide have been studied. It is shown that complete uranium cyclopentadienyl π-complex-tetracyclopentadienyluranium - in pentane under normal conditions for 100 hr reacts with carbon oxide and dioxide with the formation of polymeric complex ([(etasup(5)-Csub(5)Hsub(5))x(-CO-)U(etasup(5)-Csub(5)Hsub(4))(-CO-)]sub(2)]sub(n), in which two uranium atoms are bonded with two bridge fragments (eta 5 -C 5 H 4 -CO-), and dimeric complex [(eta 5 -C 5 H 5 ) 2 UH 2 xCO 2 ] 2 respectively

  2. Heterogeneously Catalysed Chemical Reactions in Carbon Dioxide Medium

    DEFF Research Database (Denmark)

    Musko, Nikolai E.

    In this PhD-study the different areas of chemical engineering, heterogeneous catalysis, supercritical fluids, and phase equilibrium thermodynamics have been brought together for selected reactions. To exploit the beneficial properties of supercritical fluids in heterogeneous catalysis, experimental...... studies of catalytic chemical reactions in dense and supercritical carbon dioxide have been complemented by the theoretical calculations of phase equilibria using advanced thermodynamic models. In the recent years, the use of compressed carbon dioxide as innovative, non-toxic and non-flammable, cheap......, and widely available reaction medium for many practical and industrial applications has drastically increased. Particularly attractive are heterogeneously catalysed chemical reactions. The beneficial use of CO2 is attributed to its unique properties at dense and supercritical states (at temperatures...

  3. Regenerable immobilized aminosilane sorbents for carbon dioxide capture applications

    Science.gov (United States)

    Gay, McMahan; Choi, Sunho; Jones, Christopher W

    2014-09-16

    A method for the separation of carbon dioxide from ambient air and flue gases is provided wherein a phase separating moiety with a second moiety are simultaneously coupled and bonded onto an inert substrate to create a mixture which is subsequently contacted with flue gases or ambient air. The phase-separating moiety is an amine whereas the second moiety is an aminosilane, or a Group 4 propoxide such as titanium (IV) propoxide (tetrapropyl orthotitanate, C.sub.12H.sub.28O.sub.4Ti). The second moiety makes the phase-separating moiety insoluble in the pores of the inert substrate. The new sorbents have a high carbon dioxide loading capacity and considerable stability over hundreds of cycles. The synthesis method is readily scalable for commercial and industrial production.

  4. The underground storages of carbon dioxide. Juridical aspects

    International Nuclear Information System (INIS)

    Bersani, F.

    2006-04-01

    In the framework of the reduction of the carbon dioxide emissions in the air, the underground storage of the CO 2 is studied. Some experimentation are already realized in the world and envisaged in France. This document aims to study the juridical aspects of these first works in France. After a presentation of the realization conditions and some recalls on the carbon dioxide its capture and storage, the natural CO 2 underground storages and the first artificial storages are discussed. The CO 2 waste qualification, in the framework of the environmental legislation is then detailed with a special task on the Lacq region. The problem of the sea underground storages is also presented. (A.L.B.)

  5. Carbon dioxide capture processes: Simulation, design and sensitivity analysis

    DEFF Research Database (Denmark)

    Zaman, Muhammad; Lee, Jay Hyung; Gani, Rafiqul

    2012-01-01

    equilibrium and associated property models are used. Simulations are performed to investigate the sensitivity of the process variables to change in the design variables including process inputs and disturbances in the property model parameters. Results of the sensitivity analysis on the steady state...... performance of the process to the L/G ratio to the absorber, CO2 lean solvent loadings, and striper pressure are presented in this paper. Based on the sensitivity analysis process optimization problems have been defined and solved and, a preliminary control structure selection has been made.......Carbon dioxide is the main greenhouse gas and its major source is combustion of fossil fuels for power generation. The objective of this study is to carry out the steady-state sensitivity analysis for chemical absorption of carbon dioxide capture from flue gas using monoethanolamine solvent. First...

  6. Carbon dioxide fixation in isolated Kalanchoe chloroplasts

    Energy Technology Data Exchange (ETDEWEB)

    Levi, C.; Gibbs, M.

    1975-07-01

    Chloroplasts isolated from Kalanchoe diagremontiana leaves were capable of photosynthesizing at a rate of 5.4 ..mu..moles of CO/sub 2/ per milligram of chlorophyll per hour. The dark rate of fixation was about 1 percent of the light rate. A high photosynthetic rate was associated with low starch content of the leaves. Ribose 5-phosphate, fructose 1, 6-diphosphate, and dithiothreitol stimulated fixation, whereas phosphoenolpyruvate and azide were inhibitors. The products of CO/sub 2/ fixation were primarily those of the photosynthetic carbon reduction cycle. (auth)

  7. Current views on the regulation of autotrophic carbon dioxide fixation via the Calvin cycle in bacteria

    NARCIS (Netherlands)

    Dijkhuizen, L.; Harder, W.

    1984-01-01

    The Calvin cycle of carbon dioxide fixation constitutes a biosynthetic pathway for the generation of (multi-carbon) intermediates of central metabolism from the one-carbon compound carbon dioxide. The product of this cycle can be used as a precursor for the synthesis of all components of cell

  8. Inhibition of Weld Corrosion in Flowing Brines Containing Carbon Dioxide

    OpenAIRE

    Alawadhi, Khaled

    2009-01-01

    The aim of this research was to study the effectiveness of a typical oilfield corrosion inhibitor, which is considered to be a green inhibitor (non toxic to the environment) in controlling internal corrosion of welded X65 pipeline steel in brines saturated with carbon dioxide at one bar pressure, under dynamic flowing conditions, over a range of temperatures. Several experimental configurations were used ranging from a simple flat plate design to a novel rotating cylinder electrode, to all...

  9. Remote operated vehicle with carbon dioxide blasting (ROVCO2)

    International Nuclear Information System (INIS)

    Resnick, A.M.

    1995-01-01

    The Remote Operated Vehicle with Carbon Dioxide Blasting (ROVCO 2 ), as shown in a front view, is a six-wheeled remote land vehicle used to decontaminate concrete floors. The remote vehicle has a high pressure Cryogenesis blasting subsystem, Oceaneering Technologies (OTECH) developed a CO 2 xY Orthogonal Translational End Effector (COYOTEE) subsystem, and a vacuum/filtration and containment subsystem. Figure 2 shows a block diagram with the various subsystems labeled

  10. Production of Solar Fuels by Photoelectrochemical Conversion of Carbon Dioxide

    OpenAIRE

    Irtem, Ibrahim Erdem

    2017-01-01

    Growing global emission of carbon dioxide gas (CO2) reflects the world’s energy dependence on fossil fuels. The conversion of CO2 emission into value-added products, like fuels completes a circular CO2 economy which requires a renewable energy conversion and storage system. Amongst a few, photo/electrochemistry has been particularly appealing thanks to its energy efficiency and enormous potential for industrial applications. Formic acid (HCOOH) production from CO2 reduction appears as an al...

  11. High-energy, short-pulse, carbon-dioxide lasers

    International Nuclear Information System (INIS)

    Fenstermacher, C.A.

    1979-01-01

    Lasers for fusion application represent a special class of short-pulse generators; not only must they generate extremely short temporal pulses of high quality, but they must do this at ultra-high powers and satisfy other stringent requirements by this application. This paper presents the status of the research and development of carbon-dioxide laser systems at the Los Alamos Scientific Laboratory, vis-a-vis the fusion requirements

  12. Heliox Improves Carbon Dioxide Removal during Lung Protective Mechanical Ventilation

    OpenAIRE

    Beurskens, Charlotte J; Brevoord, Daniel; Lagrand, Wim K; van den Bergh, Walter M; Vroom, Margreeth B; Preckel, Benedikt; Horn, Janneke; Juffermans, Nicole P

    2014-01-01

    Introduction. Helium is a noble gas with low density and increased carbon dioxide (CO2) diffusion capacity. This allows lower driving pressures in mechanical ventilation and increased CO2 diffusion. We hypothesized that heliox facilitates ventilation in patients during lung-protective mechanical ventilation using low tidal volumes. Methods. This is an observational cohort substudy of a single arm intervention study. Twenty-four ICU patients were included, who were admitted after a cardiac arr...

  13. Effect Of Geothermal Heat Pump On Carbon Dioxide Emissions

    Directory of Open Access Journals (Sweden)

    Ahmed F. Atwan

    2015-08-01

    Full Text Available In this research the calculations of carbon dioxide emissions CO2 in summer May to September 150 day and winter seasons December to February 90 day were performed by using the coefficient of performance for each air and ground source heat pump. The place of study case take relative to solar path in to account and the study case was three halls men women and surgery halls in Al-Musayyib hospital in Babylon.

  14. Titanium dioxide, single-walled carbon nanotube composites

    Science.gov (United States)

    Yao, Yuan; Li, Gonghu; Gray, Kimberly; Lueptow, Richard M.

    2015-07-14

    The present invention provides titanium dioxide/single-walled carbon nanotube composites (TiO.sub.2/SWCNTs), articles of manufacture, and methods of making and using such composites. In certain embodiments, the present invention provides membrane filters and ceramic articles that are coated with TiO.sub.2/SWCNT composite material. In other embodiments, the present invention provides methods of using TiO.sub.2/SWCNT composite material to purify a sample, such as a water or air sample.

  15. The effect of carbon dioxide therapy on composite graft survival

    OpenAIRE

    Durães, Eliana Ferreira Ribeiro; Durães, Leonardo de Castro; Carneiro, Fabiana Pirani; Lino Júnior, Ruy de Souza; Sousa, João Batista de

    2013-01-01

    PURPOSE: To investigate the effect of carboxytherapy in auricular composite grafts in rabbits. METHODS: An experimental study was conducted using 20 rabbits randomly assigned to a treatment group of carboxytherapy or a control group of saline solution. In each ear, a circular graft with 1.5 cm or 2 cm of diameter was amputated and reattached. Animals underwent carbon dioxide or saline injection four times during the experiment. We analyzed clinical evolution of the animals, grafts survival, h...

  16. Efficiency of Carbon Dioxide Fractional Laser in Skin Resurfacing

    Directory of Open Access Journals (Sweden)

    Andrej Petrov

    2016-05-01

    CONCLUSION: Multifunctional fractional carbon dioxide laser used in treatment of patients with acne and pigmentation from acne, as well as in the treatment of scars from different backgrounds, is an effective and safe method that causes statistically significant better effect of the treatment, greater patients’ satisfaction, minimal side effects and statistically better response to the therapy, according to assessments by the patient and the therapist.

  17. Renewable Methane Generation from Carbon Dioxide and Sunlight.

    Science.gov (United States)

    Steinlechner, Christoph; Junge, Henrik

    2018-01-02

    The direct approach: Methane is a potential key player in the world's transition to a more sustainable energy future. The direct conversion of carbon dioxide into methane is highly desirable to lower the concentration of CO 2 in the atmosphere and also to store renewable energy. This Highlight describes the first homogeneous system for the light-driven conversion of CO 2 into CH 4 . © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Spontaneous oxygen isotope exchange between carbon dioxide and\

    Czech Academy of Sciences Publication Activity Database

    Knížek, Antonín; Zukalová, Markéta; Kavan, Ladislav; Zukal, Arnošt; Kubelík, Petr; Rojík, P.; Skřehot, P.; Ferus, Martin; Civiš, Svatopluk

    2017-01-01

    Roč. 137, MAR 2017 (2017), s. 6-10 ISSN 0169-1317 R&D Projects: GA MŠk LD14115; GA ČR(CZ) GA14-12010S; GA ČR GA13-07724S; GA MŠk(CZ) LM2015073 Institutional support: RVO:61388955 Keywords : clay * carbon dioxide * FTIR spectroscopy Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 3.101, year: 2016

  19. Determination of carbon chlorine and fluorine in uranium dioxide

    International Nuclear Information System (INIS)

    Kijko, N.I.; Timofeev, G.A.

    1983-01-01

    Techniques of chlorine and fluorine determination and simultaneous determination of carbon and chlorine in electrolytic uranium dioxide are described. The method of chlorine and fluorine determination is based on their separation during oxide pyrohydrolysis with subsequent spectrophotometric analysis of condensate. Lower determination limits constitute 1 μg for chlorine, 0.5 μg for fluorine. Relative standard deviation when the content of impurities analyzed is 10 -3 % constitutes 0.05-0.07

  20. Characterization of a capillary plasma reactor for carbon dioxide decomposition

    International Nuclear Information System (INIS)

    Mori, Shinsuke; Yamamoto, Aguru; Suzuki, Masaaki

    2006-01-01

    The decomposition of carbon dioxide in a plasma reactor was investigated experimentally, using capillary discharge tubes with a diameter of 0.5 or 3.0 mm and a length of 25, 50, 75, 100 or 150 mm. The chemical composition of the reaction products and the current-voltage characteristics were measured over a pressure range of 3.33-120 Torr, and the CO 2 conversion rates and reduced electric fields were calculated. The results show that the influence of downscaling on the reduced electric fields can be well evaluated by adjusting both the current density, i, and the products of the pressure and the tube diameter, pd. However, the characteristics of CO 2 decomposition cannot be determined based on i and pd; they are better characterized by i and p. It can be deduced from our experimental results that the CO 2 conversion rate is predominated by the electron impact CO 2 dissociation and gas phase reverse reactions even in a capillary plasma reactor

  1. Recurrence of vocal fold leukoplakia after carbon dioxide laser therapy.

    Science.gov (United States)

    Chen, Min; Chen, Jian; Cheng, Lei; Wu, Haitao

    2017-09-01

    This work aims to analyze the recurrence of vocal fold leukoplakia after carbon dioxide (CO 2 ) laser resection. In this retrospective study, all patients undergoing CO 2 laser resection of vocal fold leukoplakia were followed up for at least 2 years. Recurrence was diagnosed as any presence of leukoplakia in the vocal cord subsequent to previous successful complete resection. A total of 326 patients with complete resection of vocal fold leukoplakia and follow-up subsequent surveillance laryngoscopy were studied. The recurrence rate, the recurrence time, and risk factors were evaluated. Of these, 52 (16.0%) patients experienced recurrence with a mean follow-up time of 50.5 ± 15.4 months. The mean time to recurrence was 16.2 ± 14.1 months. Univariate analysis showed that the size of lesion (P vocal fold leukoplakia, long-term follow-up is required after CO 2 laser resection. In conclusion, the size of lesion combined with the pathological grade are important risk factors that predict vocal fold leukoplakia recurrence.

  2. Study on carbon dioxide conversion by radiation

    International Nuclear Information System (INIS)

    Cho, Young Hyun; Park, Geun Il; Cho, Il Hoon; Choi, Sang Do; Hong, Kwang Hee; Lee, Chang Woo

    1999-09-01

    This study was carried out to investigate the synergistic effects on the CO 2 conversion by the application of semiconductor in the field of gamma-ray. Gamma-ray irradiation was performed to examine the effects of semiconductor application on CO 2 conversion in water and the formation of organic material from carbonate solution. From experimental results it is clear that the supplication of semiconductor in the field of gamma-ray increases the efficiency for CO 2 conversion to organic matter. Based on the obtained experimental results it is obvious that the synergistic effects of semiconductor materials in the gamma-ray field leads to increase of the CO 2 conversion yield to organic matter up to 50 percent compared to the gamma-ray irradiation. The way of achieving higher activity is due to the catalytic action of semiconductor by gamma-ray irradiation. Zr-doped TiO 2 catalyst prepared by sol-gel method exhibits the higher efficiency for CO 2 conversion in aqueous solution and carbonate containing solution. This effect of Zr-doping can be explained by the formation of additional defects in surface of TiO 2 film. (author)

  3. Exponential growth and atmospheric carbon dioxide

    International Nuclear Information System (INIS)

    Laurmann, J.A.; Rotty, R.M.

    1983-01-01

    The adequacy of assumptions required to project atmospheric CO 2 concentrations in time frames of practical importance is reviewed. Relevant issues concern the form assumed for future fossil fuel release, carbon cycle approximations, and the implications of revisions in fossil fuel patterns required to maintain atmospheric CO 2 levels below a chosen threshold. In general, we find that with a judiciously selected exponential fossil fuel release rate, and with a constant airborn fraction, we can estimate atmospheric CO 2 growth over the next 50 years based on essentially surprise free scenarios. Resource depletion effects must be included for projections beyond about 50 years, and on this time frame the constant airborne fraction approximation has to be questioned as well (especially in later years when the fossil fuel use begins to taper off). For projections for over 100 years, both energy demand scenarios and currently available carbon cycle models have sufficient uncertainties that atmospheric CO 2 levels derived from them are not much better than guesses

  4. Minimizing emission of carbon dioxide in the coconut processing

    International Nuclear Information System (INIS)

    Lozada, Ernesto P.

    1998-01-01

    About 90% of the world's coconut production is made into copra. There are 2-3 million smoke kilns which are used by the coconut farmers for making copra. It is estimated that these kilns emit carbon dioxide from 247 to 366 gram of carbon per kg of copra produced. From the world copra production of 10 M tons, the total carbon released in copra making range is 2-3 Tg(telegram=10 12 grams) or 2-3M tons of carbon per year. To minimize carbon dioxide emission in copra making, kilns with better combustion characteristics and heat utilization efficiencies must be used. One of the most promising alternative dryers is a direct-fired, natural draft dryer known as the Los Banos (Lozada) Dryer. Developed at the University of the Philippines Los Banos, the dryer consist of a simple burner, a heat distributor and a drying bin. The burner combust coconut shell, corn cob, and wood pieces with extremely high efficiency thus minimizing fuel consumption and dramatically reducing the release of airborne pollutants. The resulting copra is practically smoke free. Tests have shown that carbon dioxide emissions from the Los Banos (Lozada) Dryer are about half of that released by the traditional smoke kilns. Furthermore, the dryer emits lower concentrations of CO (50 ppm vs 2000-3000 ppm), of NO x (5 ppm vs 400 ppm), and SO x (5 ppm vs 400 ppm). When used widely, significant reductions in the emissions of greenhouse and acid rain gases from biomass combustion will be attained. (About 500 units of the Los Banos (Lozada) Dryer are now in use in the Philippines and Papua New Guinea). (Author)

  5. Nanostructured membrane material designed for carbon dioxide separation

    KAUST Repository

    Yave, Wilfredo; Car, Anja; Peinemann, Klaus-Viktor

    2010-01-01

    In this work carbon dioxide selective membrane materials from a commercially available poly(amide-b-ethylene oxide) (Pebax (R), Arkema) blended with polyethylene glycol ethers are presented. The preferred PEG-ether was PEG-dimethylether (PEG-DME). PEG-DME is well known as a physical solvent for acid gas absorption. It is used under the trade name Genosorb (R) in the Selexol (R) process (UOP) for acid gas removal from natural gas and synthesis gas. The combination of the liquid absorbent with the multiblock copolymer resulted in mechanically stable films with superior CO(2) separation properties. The addition of 50 wt.% PEG-DME to the copolymer resulted in a 8-fold increase of the carbon dioxide permeability; the CO(2)/H(2)-selectivity increased simultaneously from 9.1 to 14.9. It is shown that diffusivity as well as solubility of carbon dioxide is strongly increased by the blending of the copolymer with PEG-ethers. (c) 2009 Elsevier B.V. All rights reserved.

  6. Irreversible climate change due to carbon dioxide emissions

    Science.gov (United States)

    Solomon, Susan; Plattner, Gian-Kasper; Knutti, Reto; Friedlingstein, Pierre

    2009-01-01

    The severity of damaging human-induced climate change depends not only on the magnitude of the change but also on the potential for irreversibility. This paper shows that the climate change that takes place due to increases in carbon dioxide concentration is largely irreversible for 1,000 years after emissions stop. Following cessation of emissions, removal of atmospheric carbon dioxide decreases radiative forcing, but is largely compensated by slower loss of heat to the ocean, so that atmospheric temperatures do not drop significantly for at least 1,000 years. Among illustrative irreversible impacts that should be expected if atmospheric carbon dioxide concentrations increase from current levels near 385 parts per million by volume (ppmv) to a peak of 450–600 ppmv over the coming century are irreversible dry-season rainfall reductions in several regions comparable to those of the “dust bowl” era and inexorable sea level rise. Thermal expansion of the warming ocean provides a conservative lower limit to irreversible global average sea level rise of at least 0.4–1.0 m if 21st century CO2 concentrations exceed 600 ppmv and 0.6–1.9 m for peak CO2 concentrations exceeding ≈1,000 ppmv. Additional contributions from glaciers and ice sheet contributions to future sea level rise are uncertain but may equal or exceed several meters over the next millennium or longer. PMID:19179281

  7. The effect of carbon dioxide therapy on composite graft survival.

    Science.gov (United States)

    Durães, Eliana Ferreira Ribeiro; Durães, Leonardo de Castro; Carneiro, Fabiana Pirani; Lino, Ruy de Souza; Sousa, João Batista de

    2013-08-01

    To investigate the effect of carboxytherapy in auricular composite grafts in rabbits. An experimental study was conducted using 20 rabbits randomly assigned to a treatment group of carboxytherapy or a control group of saline solution. In each ear, a circular graft with 1.5 cm or 2 cm of diameter was amputated and reattached. Animals underwent carbon dioxide or saline injection four times during the experiment. We analyzed clinical evolution of the animals, grafts survival, histopathology features and histomorphometry of collagen. The treated group had a significantly lower weight gain (p=0.038). Histopathology was not significantly different between groups. There was an increase in amount of collagen in 2 cm grafts submitted to carbon dioxide therapy (p=0.003). Carboxytherapy didn't influence graft survival rate for 1.5 cm grafts or 2 cm grafts (p=0.567 and p=0.777, respectively). Carbon dioxide therapy increased the amount of collagen in 2 cm grafts. CO2 was not significantly different from saline infusion on composite grafts survival, but this study suggests that there is a mechanical effect caused by distension which favored graft survival.

  8. Nanostructured membrane material designed for carbon dioxide separation

    KAUST Repository

    Yave, Wilfredo

    2010-03-15

    In this work carbon dioxide selective membrane materials from a commercially available poly(amide-b-ethylene oxide) (Pebax (R), Arkema) blended with polyethylene glycol ethers are presented. The preferred PEG-ether was PEG-dimethylether (PEG-DME). PEG-DME is well known as a physical solvent for acid gas absorption. It is used under the trade name Genosorb (R) in the Selexol (R) process (UOP) for acid gas removal from natural gas and synthesis gas. The combination of the liquid absorbent with the multiblock copolymer resulted in mechanically stable films with superior CO(2) separation properties. The addition of 50 wt.% PEG-DME to the copolymer resulted in a 8-fold increase of the carbon dioxide permeability; the CO(2)/H(2)-selectivity increased simultaneously from 9.1 to 14.9. It is shown that diffusivity as well as solubility of carbon dioxide is strongly increased by the blending of the copolymer with PEG-ethers. (c) 2009 Elsevier B.V. All rights reserved.

  9. Balance of emissions and consumptions of carbon dioxide in Spain

    International Nuclear Information System (INIS)

    Valero, A.; Subiela, V.; Cortes, C.

    1994-01-01

    The amount of carbon dioxide in atmosphere increase due to deforestation and anthropogenic emissions. The consumption of this gas in vegetal ecosystems must also be considered to know the net mass of CO 2 that gets into the atmosphere. This article summarizes the methodology, results and conclusions of the carbon dioxide balance in Spain by autonomous communities. The different fossil fuel consumer sectors (Thermal power plants, industry, transport, domestic and agricultural), forest biomass reduction due to fires and wood extractions for firewood are considered as sources. As sinks, natural and reforested forests, and the equivalent sea are noticed. Basically, the article presents a new methodology to estimate carbon dioxide consumption in forest biomass. The average emissions for 1981 to 1990 are presented. A per capita value of 5 t(CO 2 /year is obtained in contrast to the EC average of 8,6 t(CO 2 ) year. The resulting net balance shows that it is only consumed between 20 and 50% of the emitted CO 2 . (Author) 47 refs

  10. Modeling the dynamics of carbon dioxide removal in the atmosphere

    Directory of Open Access Journals (Sweden)

    Shyam Sundar

    2014-12-01

    Full Text Available The temperature of Earth's surface is increasing over the past few years due to emission of global warming gases such as CO2, CH4 and NOx from industries, power plants, etc., leading to several adverse effects on human and his environment. Therefore, the question of their removal/reduction from the atmosphere is very important. In this paper, a nonlinear mathematical model to study the removal/reduction of carbon dioxide by using suitable absorbent (such as aqueous ammonia solution, amines, sodium hydroxide, etc. near the source of emission and externally introducing liquid species in the atmosphere is presented. Dynamical properties of the model which include local and global stabilities for the equilibrium are analyzed carefully. Model analysis is performed by considering three physical situations i.e. when both absorbent and the liquid species are used, only absorbent is used and only liquid species is used. It is shown that the concentration of carbon dioxide decreases as the rate of introduction of absorbent in the absorber increases. It decreases further as the rate of introduction of liquid species. Thus, the concentration of carbon dioxide would be reduced by a large amount if adequate amount of absorbent is used near the source of emission. The remaining amount can be reduced further by infusing liquid drops in the atmosphere. Numerical simulations are also carried out to support the analytical results.

  11. Diffuse volcanic emissions of carbon dioxide from Vulcano Island, Italy.

    Science.gov (United States)

    Baubron, J C; Allard, P; Toutain, J P

    1990-03-01

    RECENT investigations on Mount Etna (Sicily)(1-3) have revealed that volcanoes may release abundant carbon dioxide not only from their active craters, but also from their flanks, as diffuse soil emanations. Here we present analyses of soil gases and air in water wells on Vulcano Island which provide further evidence of such lateral degassing. Nearly pure carbon dioxide, enriched in helium and radon, escapes from the slopes of the Fossa active cone, adding a total output of 30 tonnes per day to the fumarolic crater discharge ( 180 tonnes CO(2) per day). This emanation has similar He/CO(2) and (13)C/(12)C ratios to those of the crater fumaroles (300%ndash;500 degrees C) and therefore a similar volcanic origin. Gases rich in carbon dioxide also escape at sea level along the isthmus between the Fossa and Vulcanello volcanic cones, but their depletion in both He and (13)C suggests a distinct source. Diffuse volcanic gas emanations, once their genetic link with central fumarole degassing has been demonstrated, can be used for continuous volcano monitoring, at safe distances from active craters. Such monitoring has been initiated at Vulcano, where soil and well emanations of nearly pure CO(2) themselves represent a threat to the local population.

  12. [Thoracoscopic thymectomy with carbon dioxide insufflation in the mediastinum].

    Science.gov (United States)

    Ferrero-Coloma, C; Navarro-Martinez, J; Bolufer, S; Rivera-Cogollos, M J; Alonso-García, F J; Tarí-Bas, M I

    2015-02-01

    The case is presented of a 71 year-old male, diagnosed with a thymoma. A thoracoscopic thymectomy was performed using the carbon dioxide insufflation technique in the mediastinum. During the procedure, while performing one-lung ventilation, the patient's respiration worsened. The contralateral lung had collapsed, as carbon dioxide was travelling from the mediastinum to the thorax through the opened pleura. Two-lung ventilation was decided upon, which clearly improved oxygenation in the arterial gases and airway pressures. Both pH and pCO2 stabilized. The surgical approach and the carbon dioxide technique were continued because 2-lung ventilation did not affect the surgical procedure. This technique has many serious complications and it should always be performed using 2-lung ventilation. Copyright © 2014 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.

  13. Effects of elevated carbon dioxide concentration on growth and N2 fixation of young Robinia pseudoacacia

    International Nuclear Information System (INIS)

    Feng, Z; Flessa, H.; Dyckmans, J.

    2004-01-01

    The effects of elevated carbon dioxide concentration on carbon and nitrogen uptake and nitrogen source partitioning were determined in one year-old locust trees using a dual 13 C and 15 N continuous labelling experiment. Elevated carbon dioxide increased the fraction of new carbon in total carbon, but it did not alter carbon partitioning among plant compartments. Elevated carbon dioxide also increased the fraction of new nitrogen in total nitrogen. This was coupled with a shift in nitrogen source partitioning toward nitrogen fixation. Soil nitrogen uptake was not affected, but nitrogen fixation was markedly increased by elevated carbon dioxide treatment. The increased nitrogen fixation tended to decrease the C/N ratio in the presence of elevated carbon dioxide. Total dry mass of root nodules doubled in response to elevated carbon dioxide, however, this effect was not considered significant because of the great variability in root nodule formation. Overall, it was concluded that the growth of locust trees in an elevated carbon dioxide environment will not primarily be limited by nitrogen availability, giving the R. pseudoacacia species a competitive advantage over non-nitrogen-fixing tree species. It was also suggested that the increase in nitrogen fixation observed in response to elevated carbon dioxide treatment may play a key role in the growth response of forest ecosystems to elevated carbon dioxide by improving nitrogen availability for non-nitrogen-fixing trees. 51 refs., 1 tab., 4 figs

  14. Developing a molecular platform for potential carbon dioxide fixing

    DEFF Research Database (Denmark)

    Mikkelsen, Mette; Jørgensen, Mikkel; Krebs, Frederik C

    2010-01-01

    This paper presents an attempt to develop a new system for fixing carbon dioxide from the atmosphere. The proposed molecular system has been designed to have the capacity to spontaneously bind CO2 from the atmosphere with high affinity. The molecular system is furthermore designed to have...... the ability to liberate CO2 at a later stage in the process, i.e., in a separate compartment. The liberated CO2 presents a carbon neutral way of obtaining pure CO2. The proposed molecular system is based on a small stable organic molecule that potentially have two forms: one without bound CO2 and one...

  15. Biotransformations of carbon dioxide in photobioreactors

    International Nuclear Information System (INIS)

    Jacob-Lopes, Eduardo; Gimenes Scoparo, Carlos Henrique; Queiroz, Maria Isabel; Franco, Telma Teixeira

    2010-01-01

    Laboratory experiments were performed to study the capacity of CO 2 sequestration and carbon fixation into biomass during the cultivation of the cyanobacteria Aphanothece microscopica Naegeli in refinery wastewater. The influence of the photoperiod (day/night) on the rates of CO 2 sequestration and O 2 release was also determined. Rates of CO 2 sequestration were measured both in the liquid and gaseous phases. The results showed that the capacity of CO 2 sequestration and O 2 release during the day/night experiment was about one-fourth less than that achieved in the continuously illuminated experiment. Equivalence was found between rates of CO 2 sequestration measured in the two phases. Despite large amounts of CO 2 that were sequestered during the cultivation, it is demonstrated that only a small fraction (about 3%) was effectively fixed as microalgae biomass, indicating the existence of other routes of CO 2 conversion in the photobioreactor.

  16. An in situ infrared study of dimethyl carbonate synthesis from carbon dioxide and methanol over zirconia

    International Nuclear Information System (INIS)

    Jung, Kyeong Taek; Bell, Alexis T.

    2001-01-01

    The mechanism of dimethyl carbonate (DMC) synthesis from methanol and carbon dioxide over monoclinic zirconia has been investigated using in situ infrared spectroscopy. The dissociative adsorption of methanol occurs more slowly than the adsorption of carbon dioxide, but the species formed from methanol are bound more strongly. Upon adsorption, the oxygen atom of methanol binds to coordinately unsaturated Zr4+ cations present at the catalyst surface. Rapid dissociation of the adsorbed methanol leads to the formation of a methoxide group (Zr-OCH3) and the release of a proton, which reacts with a surface hydroxyl group to produce water. Carbon dioxide inserts in the Zr-O bond of the methoxide to form a mondentate methyl carbonate group (Zr-OC(O)OCH3). This process is facilitated by the interactions of C and O atoms in CO2 with Lewis acid-base pairs of sites (Zr4+O2-) on the surface of the catalyst. Methyl carbonate species can also be produced via the reaction of methanol with carbon dioxide adsorbed in the form of bicarbonate species with methanol, a process that results in the transfer of a methyl group to the carbonate and restores a hydroxyl group to the zirconia surface. The decomposition of DMC on monoclinic zirconia has also been investigated and has been observed to occur via the reverse of the processes described for the synthesis of DMC

  17. Arbuscular mycorrhizal fungi increase organic carbon decomposition under elevated carbon dioxide

    Science.gov (United States)

    A major goal of climate change research is to understand whether and how terrestrial ecosystems can sequester more carbon to mitigate rising atmospheric carbon dioxide (CO2) levels. The stimulation of arbuscular mycorrhizal fungi (AMF) by elevated atmospheric CO2 has been assumed to be a major mecha...

  18. Electrocatalytic reduction of carbon dioxide under plasma DBD process

    International Nuclear Information System (INIS)

    Amouroux, Jacques; Cavadias, Simeon

    2017-01-01

    Carbon dioxide can be converted, by reaction with hydrogen, into fine chemicals and liquid fuels such as methanol and DME. Methane production by the Sabatier reaction opens the way of carbon recycling for a circular economy of carbon resources. The catalytic process of methanation of carbon dioxide produces two molecules of water as a by-product. A current limitation in the CO 2 methanation is the ageing of catalysts, mainly due to water adsorption during the process. To avoid this adsorption, the process is operated at high temperature (300 °C–400 °C), leading to carbon deposition on the catalyst and its deactivation. To overcome this problem, a methanation plasma-catalytic process has been developed, which achieves high CO 2 conversion rate (80%), and a selectivity close to 100%, working from room temperature to 150 °C, instead of 300 °C–400 °C for the thermal catalytic process. The main characteristics of this process are high-voltage pulses of few nanoseconds duration, activating the adsorption of CO 2 in bent configuration and the polarization of the catalyst. The key step in this process is the desorption of water from the polarized catalyst. The high CO 2 conversion at low temperature could be explained by the creation of a plasma inside the nanopores of the catalyst. (paper)

  19. Electrocatalytic reduction of carbon dioxide under plasma DBD process

    Science.gov (United States)

    Amouroux, Jacques; Cavadias, Simeon

    2017-11-01

    Carbon dioxide can be converted, by reaction with hydrogen, into fine chemicals and liquid fuels such as methanol and DME. Methane production by the Sabatier reaction opens the way of carbon recycling for a circular economy of carbon resources. The catalytic process of methanation of carbon dioxide produces two molecules of water as a by-product. A current limitation in the CO2 methanation is the ageing of catalysts, mainly due to water adsorption during the process. To avoid this adsorption, the process is operated at high temperature (300 °C-400 °C), leading to carbon deposition on the catalyst and its deactivation. To overcome this problem, a methanation plasma-catalytic process has been developed, which achieves high CO2 conversion rate (80%), and a selectivity close to 100%, working from room temperature to 150 °C, instead of 300 °C-400 °C for the thermal catalytic process. The main characteristics of this process are high-voltage pulses of few nanoseconds duration, activating the adsorption of CO2 in bent configuration and the polarization of the catalyst. The key step in this process is the desorption of water from the polarized catalyst. The high CO2 conversion at low temperature could be explained by the creation of a plasma inside the nanopores of the catalyst.

  20. End-tidal carbon dioxide (ETCO2) can replace methods for measuring partial pressure of carbon dioxide (PCO2) in pigs

    DEFF Research Database (Denmark)

    Alstrup, Aage Kristian Olsen

    2017-01-01

    We compared end-tidal carbon dioxide (ETCO2) with partial pressure of carbon dioxide (PCO2) in domestic pigs anesthetized for neuroscience. There was good agreement between ETCO2 and PCO2 under both hypocapnia, normocapnia, and hypercapnia conditions. ETCO2 saves time by continually providing...

  1. Kinetic of formation for single carbon dioxide and mixed carbon dioxide and tetrahydrofuran hydrates in water and sodium chloride aqueous solution

    NARCIS (Netherlands)

    Sabil, K.M.; Duarte, A.R.C.; Zevenbergen, J.F.; Ahmad, M.M.; Yusup, S.; Omar, A.A.; Peters, C.J.

    2010-01-01

    A laboratory-scale reactor system is built and operated to measure the kinetic of formation for single and mixed carbon dioxide-tetrahydrofuran hydrates. The T-cycle method, which is used to collect the kinetic data, is briefly discussed. For single carbon dioxide hydrate, the induction time

  2. Fluxes of Methane and Carbon Dioxide from a Subarctic Lake

    DEFF Research Database (Denmark)

    Jammet, Mathilde Manon

    ) and carbon dioxide (CO2) with the atmosphere. Yet uncertainties in the magnitude and drivers of these fluxes remain, partly due to a lack of direct observations covering all seasons of the year, but also because of the diversity in measurement methods that often miss components of the transport processes......Ongoing climate warming is expected to affect the carbon functioning of subarctic ecosystems. Lakes and wetlands, which are common ecosystems of the high northern latitudes, are of utmost interest in this context because they exchange large amounts of the climate-forcing gases methane (CH4......-out and the release of CH4 and CO2 was established. These results underline the crucial importance of shoulder seasons in the annual carbon emissions from seasonally frozen lakes. Overall, the lake was an important annual source of carbon to the atmosphere, partially compensating the higher, annual sink function...

  3. Carbon dioxide concentrations are very high in developing oilseeds.

    Science.gov (United States)

    Goffman, Fernando D; Ruckle, Mike; Ohlrogge, John; Shachar-Hill, Yair

    2004-09-01

    A new method has been developed to rapidly determine the total inorganic carbon concentration (gaseous [CO2] + aqueous [CO(2)] + [HCO3-] + [CO3(2)-]) in developing seeds. Seeds are rapidly dissected and homogenized in 1 N HCl in gas-tight vials. The headspace gas is then analyzed by infrared gas analysis. Developing rapeseed (Brassica napus L.) and soybean [Glycine max (L.) Merr.] seeds were analyzed and found to have up to 40 and 12 mM total inorganic carbon, respectively. These concentrations are ca. 600-2000-fold higher than in ambient air or values reported for leaves. Carbon dioxide concentrations in rapeseed peaked during the stage of maximum oil synthesis and declined as seeds matured. The consequences for seed metabolism, physiology and carbon economy are discussed.

  4. Amazon River carbon dioxide outgassing fuelled by wetlands.

    Science.gov (United States)

    Abril, Gwenaël; Martinez, Jean-Michel; Artigas, L Felipe; Moreira-Turcq, Patricia; Benedetti, Marc F; Vidal, Luciana; Meziane, Tarik; Kim, Jung-Hyun; Bernardes, Marcelo C; Savoye, Nicolas; Deborde, Jonathan; Souza, Edivaldo Lima; Albéric, Patrick; Landim de Souza, Marcelo F; Roland, Fabio

    2014-01-16

    River systems connect the terrestrial biosphere, the atmosphere and the ocean in the global carbon cycle. A recent estimate suggests that up to 3 petagrams of carbon per year could be emitted as carbon dioxide (CO2) from global inland waters, offsetting the carbon uptake by terrestrial ecosystems. It is generally assumed that inland waters emit carbon that has been previously fixed upstream by land plant photosynthesis, then transferred to soils, and subsequently transported downstream in run-off. But at the scale of entire drainage basins, the lateral carbon fluxes carried by small rivers upstream do not account for all of the CO2 emitted from inundated areas downstream. Three-quarters of the world's flooded land consists of temporary wetlands, but the contribution of these productive ecosystems to the inland water carbon budget has been largely overlooked. Here we show that wetlands pump large amounts of atmospheric CO2 into river waters in the floodplains of the central Amazon. Flooded forests and floating vegetation export large amounts of carbon to river waters and the dissolved CO2 can be transported dozens to hundreds of kilometres downstream before being emitted. We estimate that Amazonian wetlands export half of their gross primary production to river waters as dissolved CO2 and organic carbon, compared with only a few per cent of gross primary production exported in upland (not flooded) ecosystems. Moreover, we suggest that wetland carbon export is potentially large enough to account for at least the 0.21 petagrams of carbon emitted per year as CO2 from the central Amazon River and its floodplains. Global carbon budgets should explicitly address temporary or vegetated flooded areas, because these ecosystems combine high aerial primary production with large, fast carbon export, potentially supporting a substantial fraction of CO2 evasion from inland waters.

  5. Dissolution of uranium dioxide in supercritical carbon dioxide modified with tri-n-butyl phosphate-hydrogen peroxide

    International Nuclear Information System (INIS)

    Kanekar, A.S.; Pathak, P.N.; Mohapatra, P.K.; Manchanda, V.K.

    2009-01-01

    Direct dissolution of uranium dioxide in supercritical carbon dioxide modified with tri-n-butyl phosphate (TBP) has been attempted. The effects of TBP concentration and pressure on the extraction of uranium have been studied. Addition of hydrogen peroxide in the modifier enhances the dissolution/extraction of uranium. (author)

  6. Reactivity of Criegee Intermediates toward Carbon Dioxide.

    Science.gov (United States)

    Lin, Yen-Hsiu; Takahashi, Kaito; Lin, Jim Jr-Min

    2018-01-04

    Recent theoretical work by Kumar and Francisco suggested that the high reactivity of Criegee intermediates (CIs) could be utilized for designing efficient carbon capture technologies. Because the anti-CH 3 CHOO + CO 2 reaction has the lowest barrier in their study, we chose to investigate it experimentally. We probed anti-CH 3 CHOO with its strong UV absorption at 365 nm and measured the rate coefficient to be ≤2 × 10 -17 cm 3 molecule -1 s -1 at 298 K, which is consistent with our theoretical value of 2.1 × 10 -17 cm 3  molecule -1 s -1 at the QCISD(T)/CBS//B3LYP/6-311+G(2d,2p) level but inconsistent with their results obtained at the M06-2X/aug-cc-pVTZ level, which tends to underestimate the barrier heights. The experimental result indicates that the reaction of a Criegee intermediate with atmospheric CO 2 (400 ppmv) would be inefficient (k eff < 0.2 s -1 ) and cannot compete with other decay processes of Criegee intermediates like reactions with water vapor (∼10 3 s -1 ) or thermal decomposition (∼10 2 s -1 ).

  7. Biotransformations of carbon dioxide in photobioreactors

    Energy Technology Data Exchange (ETDEWEB)

    Jacob-Lopes, Eduardo [School of Agricultural Engineering, Federal University of Pelotas, UFPel, 96010-900 Pelotas-RS (Brazil); Gimenes Scoparo, Carlos Henrique; Franco, Telma Teixeira [School of Chemical Engineering, State University of Campinas, UNICAMP, P.O. Box 6066, 13083-970 Campinas-SP (Brazil); Queiroz, Maria Isabel [School of Chemistry and Food, Federal University of Rio Grande, FURG, 96201-900 Rio Grande-RS (Brazil)

    2010-05-15

    Laboratory experiments were performed to study the capacity of CO{sub 2} sequestration and carbon fixation into biomass during the cultivation of the cyanobacteria Aphanothece microscopica Naegeli in refinery wastewater. The influence of the photoperiod (day/night) on the rates of CO{sub 2} sequestration and O{sub 2} release was also determined. Rates of CO{sub 2} sequestration were measured both in the liquid and gaseous phases. The results showed that the capacity of CO{sub 2} sequestration and O{sub 2} release during the day/night experiment was about one-fourth less than that achieved in the continuously illuminated experiment. Equivalence was found between rates of CO{sub 2} sequestration measured in the two phases. Despite large amounts of CO{sub 2} that were sequestered during the cultivation, it is demonstrated that only a small fraction (about 3%) was effectively fixed as microalgae biomass, indicating the existence of other routes of CO{sub 2} conversion in the photobioreactor. (author)

  8. Fischer-Tropsch synthesis in supercritical phase carbon dioxide: Recycle rates

    Science.gov (United States)

    Soti, Madhav

    With increasing oil prices and attention towards the reduction of anthropogenic CO2, the use of supercritical carbon dioxide for Fischer Tropsch Synthesis (FTS) is showing promise in fulfilling the demand of clean liquid fuels. The evidence of consumption of carbon dioxide means that it need not to be removed from the syngas feed to the Fischer Tropsch reactor after the gasification process. Over the last five years, research at SIUC have shown that FTS in supercritical CO2reduces the selectivities for methane, enhances conversion, reduces the net CO2produces in the coal to liquid fuels process and increase the life of the catalyst. The research has already evaluated the impact of various operating and feed conditions on the FTS for the once through process. We believe that the integration of unreacted feed recycle would enhance conversion, increase the yield and throughput of liquid fuels for the same reactor size. The proposed research aims at evaluating the impact of recycle of the unreacted feed gas along with associated product gases on the performance of supercritical CO2FTS. The previously identified conditions will be utilized and various recycle ratios will be evaluated in this research once the recycle pump and associated fittings have been integrated to the supercritical CO2FTS. In this research two different catalysts (Fe-Zn-K, Fe-Co-Zn-K) were analyzed under SC-FTS in different recycle rate at 350oC and 1200 psi. The use of recycle was found to improve conversion from 80% to close to 100% with both catalysts. The experiment recycle rate at 4.32 and 4.91 was clearly surpassing theoretical recycle curve. The steady state reaction rate constant was increased to 0.65 and 0.8 min-1 for recycle rate of 4.32 and 4.91 respectively. Carbon dioxide selectivity was decreased for both catalyst as it was converting to carbon monoxide. Carbon dioxide consumption was increased from 0.014 to 0.034 mole fraction. This concluded that CO2is being used in the system and

  9. Modulation of magmatic processes by carbon dioxide

    Science.gov (United States)

    Caricchi, L.; Sheldrake, T. E.; Blundy, J. D.

    2017-12-01

    Volatile solubility in magmas increases with pressure, although the solubility of CO2 is much lower than that of H2O. Consequently, magmas rising from depth release CO2-rich fluids, which inevitably interact with H2O-poor magmas in the upper crust (CO2-flushing). CO2-flushing triggers the exsolution of H2O-rich fluids, leading to an increase of volume and magma crystallisation. While the analyses of eruptive products demonstrates that this process operates in virtually all magmatic system, its impact on magmatic and volcanic processes has not been quantified. Here we show that depending on the initial magma crystallinity, and the depth of magma storage, CO2-flushing can lead to volcanic eruptions or promote conditions that favour the impulsive release of mineralising fluids. Our calculations show that the interaction between a few hundred ppm of carbonic fluids, and crystal-poor magmas stored at shallow depths, produces rapid pressurisation that can potentially lead to an eruption. Further addition of CO2 increases magma compressibility and crystallinity, reducing the potential for volcanic activity, promoting the formation of ore deposits. Increasing the depth of fluid-magma interaction dampens the impact of CO2-flushing on the pressurisation of a magma reservoir. CO2-flushing may result in surface inflation and increases in surface CO2 fluxes, which are commonly considered signs of an impending eruption, but may not necessarily result in eruption depending on the initial crystallnity and depth of the magmatic reservoir. We propose that CO2-flushing is a powerful agent modulating the pressurisation of magma reservoirs and the release of mineralising fluids from upper crustal magma reservoirs.

  10. Carbon dioxide emissions from Indian monsoonal estuaries

    Science.gov (United States)

    Sarma Vedula, VSS

    2012-07-01

    The oceans act as a net sink for atmospheric CO2, however, the role of coastal bodies on global CO2 fluxes remains unclear due to lack of data. The estimated absorption of CO2 from the continental shelves, with limited data, is 0.22 to 1.0 PgC/y, and of CO2 emission by estuaries to the atmosphere is 0.27 PgC/y. The estimates from the estuaries suffer from large uncertainties due to large variability and lack of systematic data collection. It is especially true for Southeast Asian estuaries as the biogeochemical cycling of material are different due to high atmospheric temperature, seasonality driven by monsoons, seasonal discharge etc. In order to quantify CO2 emissions from the Indian estuaries, samples were collected at 27 estuaries all along the Indian coast during discharge wet and dry periods. The emissions of CO2 to the atmosphere from Indian estuaries were 4-5 times higher during wet than dry period. The pCO2 ranged between ~300 and 18492 microatm which were within the range of world estuaries. The mean pCO2 and particulate organic carbon (POC) showed positive relation with rate of discharge suggesting availability of high quantities of organic matter that led to enhanced microbial decomposition. The annual CO2 fluxes from the Indian estuaries, together with dry period data available in the literature, amounts to 1.92 TgC which is >10 times less than that from the European estuaries. The low CO2 fluxes from the Indian estuaries are attributed to low flushing rates and less human settlements along the banks of the Indian estuaries.

  11. Kinetics of the exchange of oxygen between carbon dioxide and carbonate in aqueous solution

    International Nuclear Information System (INIS)

    Tu, C.K.; Silverman, D.N.

    1975-01-01

    A kinetic analysis of the exchange of oxygen between carbon dioxide and carbonate ion in alkaline, aqueous solutions is presented. The exchange was observed by placing 18 O-labeled carbonate, not enriched in 13 C, into solution with 13 C-enriched carbonate, not enriched in 18 O. The rate of depletion of 18 O from the 12 C-containing species and the rate of appearance of 18 O in the 13 C-containing species was measured by mass spectrometry. From these data, the second-order rate constant for the reaction between carbon dioxide and carbonate which results in the exchange of oxygen at 25 0 is 114 +- 11 M -1 sec -1 . It is emphasized that this exchange of oxygen between species of CO 2 in solution must be recognized in studies using 18 O labels to determine the fate of CO 2 in biochemical and physiological processes. (auth)

  12. Long term carbon dioxide exchange above a mixed forest in the Belgian Ardennes: evaluation of different approaches to deduce total ecosystem respiration from Eddy covariance measurements

    Science.gov (United States)

    Jérôme, Elisabeth; Aubinet, Marc; Heinesch, Bernard

    2010-05-01

    The general aim of this research is to analyze inter annual variability of carbon dioxide (CO2) fluxes exchanged by a mixed forest located at the Vielsalm experimental site in Belgium. At this site, CO2 flux measurements started in 1996 and are still going on. Thirteen complete years of measurements are thus available. Net Ecosystem Exchange (NEE) inter annual variability may be driven by gross primary productivity (GPP) or Total Ecosystem Respiration (TER), which should thus be both quantified. Using flux partitioning methods, TER is deduced from NEE measurements. GPP is then obtained by subtracting TER from NEE. Initially, a robust estimation of TER is required. This work seeks to compare two independent approaches to assess TER in order to quantify the implications on inter-annual variability. The comparison was performed on twelve complete years. TER estimates can be deduced by extrapolating to the whole day NEE measurements taken during selected night or day periods. In both case, the extrapolation is performed by using a respiration response to temperature. The first approach, referred as the night-time approach, consisted in calculating TER using a temperature response function derived from night-time data sets (Reichstein et al., 2005). The second approach, referred as the daytime approach, consisted in assessing TER from the intercept of the NEE/Photosynthetically Photon Flux Density (PPFD) response (Wohlfahrt et al., 2005). For each approach, different modalities were compared: the use of long term (annual) or short term (15 days) data sets for the night-time approach and the use of different types of regression for the daytime approach. In addition, the impact of the temperature choice was studied for each of the approaches. For the night-time approach, main results showed that air temperature sensitivity of ecosystem respiration derived from annual data did not reflect the short-term air temperature sensitivity. Vielsalm is a summer active ecosystem

  13. Selected constituents in the smokes of foreign commercial cigaretts: tar, nicotine, carbon monoxide, and carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, R.A.; Quincy, R.B.; Guerin, M.R.

    1979-05-01

    The tar, nicotine, carbon monoxide, and carbon dioxide contents of the smokes of 220 brands of foreign commercial cigarettes are reported. In some instances, filter cigarettes of certain brands were found to deliver as much or more smoke constituents than their nonfilter counterparts. Also, data indicated that there can be a great variation in the tar, nicotine, or carbon monoxide content of the smoke of samples of a given brand of cigarettes, depending on the nation in which they are purchased. 24 tables.

  14. Carbon materials-functionalized tin dioxide nanoparticles toward robust, high-performance nitrogen dioxide gas sensor.

    Science.gov (United States)

    Zhang, Rui; Liu, Xiupeng; Zhou, Tingting; Wang, Lili; Zhang, Tong

    2018-08-15

    Carbon (C) materials, which process excellent electrical conductivity and high carrier mobility, are promising sensing materials as active units for gas sensors. However, structural agglomeration caused by chemical processes results in a small resistance change and low sensing response. To address the above issues, structure-derived carbon-coated tin dioxide (SnO 2 ) nanoparticles having distinct core-shell morphology with a 3D net-like structure and highly uniform size are prepared by careful synthesis and fine structural design. The optimum carbon-coated SnO 2 nanoparticles (SnO 2 /C)-based gas sensor exhibits a low working temperature, excellent selectivity and fast response-recovery properties. In addition, the SnO 2 /C-based gas sensor can maintain a sensitivity to nitrogen dioxide (NO 2 ) of 3 after being cycled 4 times at 140 °C for, suggesting its good long-term stability. The structural integrity, good synergistic properties, and high gas-sensing performance of SnO 2 /C render it a promising sensing material for advanced gas sensors. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. CARBON DIOXIDE MITIGATION THROUGH CONTROLLED PHOTOSYNTHESIS; FINAL

    International Nuclear Information System (INIS)

    Unknown

    2000-01-01

    This research was undertaken to meet the need for a robust portfolio of carbon management options to ensure continued use of coal in electrical power generation. In response to this need, the Ohio Coal Research Center at Ohio University developed a novel technique to control the emissions of CO(sub 2) from fossil-fired power plants by growing organisms capable of converting CO(sub 2) to complex sugars through the process of photosynthesis. Once harvested, the organisms could be used in the production of fertilizer, as a biomass fuel, or fermented to produce alcohols. In this work, a mesophilic organism, Nostoc 86-3, was examined with respect to the use of thermophilic algae to recycle CO(sub 2) from scrubbed stack gases. The organisms were grown on stationary surfaces to facilitate algal stability and promote light distribution. The testing done throughout the year examined properties of CO(sub 2) concentration, temperature, light intensity, and light duration on process viability and the growth of the Nostoc. The results indicate that the Nostoc species is suitable only in a temperature range below 125 F, which may be practical given flue gas cooling. Further, results indicate that high lighting levels are not suitable for this organism, as bleaching occurs and growth rates are inhibited. Similarly, the organisms do not respond well to extended lighting durations, requiring a significant (greater than eight hour) dark cycle on a consistent basis. Other results indicate a relative insensitivity to CO(sub 2) levels between 7-12% and CO levels as high as 800 ppm. Other significant results alluded to previously, relate to the development of the overall process. Two processes developed during the year offer tremendous potential to enhance process viability. First, integration of solar collection and distribution technology from Oak Ridge laboratories could provide a significant space savings and enhanced use of solar energy. Second, the use of translating slug flow

  16. CARBON DIOXIDE MITIGATION THROUGH CONTROLLED PHOTOSYNTHESIS

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2000-10-01

    This research was undertaken to meet the need for a robust portfolio of carbon management options to ensure continued use of coal in electrical power generation. In response to this need, the Ohio Coal Research Center at Ohio University developed a novel technique to control the emissions of CO{sub 2} from fossil-fired power plants by growing organisms capable of converting CO{sub 2} to complex sugars through the process of photosynthesis. Once harvested, the organisms could be used in the production of fertilizer, as a biomass fuel, or fermented to produce alcohols. In this work, a mesophilic organism, Nostoc 86-3, was examined with respect to the use of thermophilic algae to recycle CO{sub 2} from scrubbed stack gases. The organisms were grown on stationary surfaces to facilitate algal stability and promote light distribution. The testing done throughout the year examined properties of CO{sub 2} concentration, temperature, light intensity, and light duration on process viability and the growth of the Nostoc. The results indicate that the Nostoc species is suitable only in a temperature range below 125 F, which may be practical given flue gas cooling. Further, results indicate that high lighting levels are not suitable for this organism, as bleaching occurs and growth rates are inhibited. Similarly, the organisms do not respond well to extended lighting durations, requiring a significant (greater than eight hour) dark cycle on a consistent basis. Other results indicate a relative insensitivity to CO{sub 2} levels between 7-12% and CO levels as high as 800 ppm. Other significant results alluded to previously, relate to the development of the overall process. Two processes developed during the year offer tremendous potential to enhance process viability. First, integration of solar collection and distribution technology from Oak Ridge laboratories could provide a significant space savings and enhanced use of solar energy. Second, the use of translating slug flow

  17. Economic effects of restricting carbon dioxide emissions

    International Nuclear Information System (INIS)

    Haaparanta, P.; Jerkkola, J.; Pohjola, J.

    1994-01-01

    The aim of this study is to evaluate the economy-wide effects of reducing CO 2 emissions. NO x and SO 2 emissions can also be included. The policy questions can be approached either by estimating the emission taxes needed to achieve the given levels of emissions or by estimating the level of emissions given the level of taxes. A computable general equilibrium (CGE) is used in this analysis. The general equilibrium models deal with long-run effects, after all markets have equilibrated and all resources are optimally used. They are particularly well-suited to analyze long-run resource allocation, welfare losses and income distribution, beyond the short-run macroeconomic disturbances and business cycle phenomena. As the general equilibrium framework integrates all main economic sectors, the feedbacks and interrelationships between the various sectors are taken into account

  18. Oxidation suppressing device for steel materials in carbon dioxide cooled reactors

    International Nuclear Information System (INIS)

    Kawakami, Haruo

    1986-01-01

    Purpose: To effectively reduce impurity hydrogens in carbon dioxide. Constitution: At least three gas chambers are arranged serially each by way of a valve in a gas flow channel branched from a primary carbon dioxide coolant circuits. Then, a polymeric partition membrane having higher permeation rate for hydrogen than for carbon dioxide, e.g., made of polytrifluorochloroethylene is disposed between first and second gas chambers and, further, the first and the third gas chambers are connected each by way of a valve to the primary carbon dioxide coolant circuit to constitute a gas recovery channel. Carbon dioxide is caused to flow through the channel by means of a pump disposed between the second and third gas chambers, hydrogen as impurity passed through the partition walls is concentrated and discharged out of the channel, while the carbon dioxide with reduced hydrogen content is returned from the first and the third gas chambers to the circuit. (Sekiya, K.)

  19. Semiconductor-Based Photoelectrochemical Conversion of Carbon Dioxide: Stepping Towards Artificial Photosynthesis.

    Science.gov (United States)

    Pang, Hong; Masuda, Takuya; Ye, Jinhua

    2018-01-18

    The photoelectrochemical (PEC) carbon dioxide reduction process stands out as a promising avenue for the conversion of solar energy into chemical feedstocks, among various methods available for carbon dioxide mitigation. Semiconductors derived from cheap and abundant elements are interesting candidates for catalysis. Whether employed as intrinsic semiconductors or hybridized with metallic cocatalysts, biocatalysts, and metal molecular complexes, semiconductor photocathodes exhibit good performance and low overpotential during carbon dioxide reduction. Apart from focusing on carbon dioxide reduction materials and chemistry, PEC cells towards standalone devices that use photohybrid electrodes or solar cells have also been a hot topic in recent research. An overview of the state-of-the-art progress in PEC carbon dioxide reduction is presented and a deep understanding of the catalysts of carbon dioxide reduction is also given. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Apparatus and method for removing solvent from carbon dioxide in resin recycling system

    Science.gov (United States)

    Bohnert, George W [Harrisonville, MO; Hand, Thomas E [Lee's Summit, MO; DeLaurentiis, Gary M [Jamestown, CA

    2009-01-06

    A two-step resin recycling system and method solvent that produces essentially contaminant-free synthetic resin material. The system and method includes one or more solvent wash vessels to expose resin particles to a solvent, the solvent contacting the resin particles in the one or more solvent wash vessels to substantially remove contaminants on the resin particles. A separator is provided to separate the solvent from the resin particles after removal from the one or more solvent wash vessels. The resin particles are next exposed to carbon dioxide in a closed loop carbon dioxide system. The closed loop system includes a carbon dioxide vessel where the carbon dioxide is exposed to the resin, substantially removing any residual solvent remaining on the resin particles after separation. A separation vessel is also provided to separate the solvent from the solvent laden carbon dioxide. Both the carbon dioxide and the solvent are reused after separation in the separation vessel.

  1. Atmospheric carbon dioxide and the global carbon cycle

    Energy Technology Data Exchange (ETDEWEB)

    Trabalka, J R [ed.

    1985-12-01

    This state-of-the-art volume presents discussions on the global cycle of carbon, the dynamic balance among global atmospheric CO2 sources and sinks. Separate abstracts have been prepared for the individual papers. (ACR)

  2. Efficiency of water removal from water/ethanol mixtures using supercritical carbon dioxide

    Directory of Open Access Journals (Sweden)

    M. A. Rodrigues

    2006-06-01

    Full Text Available Techniques involving supercritical carbon dioxide have been successfully used for the formation of drug particles with controlled size distributions. However, these processes show some limitations, particularly in processing aqueous solutions. A diagram walking algorithm based on available experimental data was developed to evaluate the effect of ethanol on the efficiency of water removal processes under different process conditions. Ethanol feeding was the key parameter resulting in a tenfold increase in the efficiency of water extraction.

  3. 76 FR 55846 - Hazardous Waste Management System: Identification and Listing of Hazardous Waste: Carbon Dioxide...

    Science.gov (United States)

    2011-09-09

    ... carbon dioxide (CO 2 ) streams that are hazardous from the definition of hazardous waste, provided these... management under the Resource Conservation and Recovery Act (RCRA) to conditionally exclude carbon dioxide... 2050-AG60 Hazardous Waste Management System: Identification and Listing of Hazardous Waste: Carbon...

  4. Fire extinction utilizing carbon dioxide hydrate

    Energy Technology Data Exchange (ETDEWEB)

    Hatakeyama, T.; Aida, E.; Yokomori, T.; Ohmura, R.; Ueda, T. [Keio Univ., Hiyoshi, Kohoku-ku, Yokohama (Japan)

    2008-07-01

    Clathrate hydrates formed with nonflammable gases may be suitable for use as fire extinguishing agents because dissociation of the hydrates results in the temperature decrease in the combustion field and the nonflammable gases released from the dissociated hydrates prevent the supply of the oxygen to the combustion field. This paper discussed experiments in which ordinary ice and dry ice were used to evaluate the performance of CO{sub 2} hydrate as a fire extinguishing agent. The paper described the apparatus and procedure for the preparation of CO{sub 2} hydrate crystals. A schematic of the reactor to form CO{sub 2} hydrate and a photograph of CO{sub 2} hydrate crystal formed in the study were also presented. Other illustrations, photographs, and tables that were presented included a schematic diagram of the experimental apparatus used for the flame extinction experiments; a photograph of CO{sub 2} hydrate powder; sequential video graphs of the flame extinction by the supply of CO{sub 2} hydrate crystals to the methanol pool flame and the relevant illustration; and heat of CO{sub 2} hydrate dissociation, water vaporization and sublimation of dry ice. It was concluded that the critical mass of the CO{sub 2} hydrate required to extinguish a flame was much less than that of ordinary ice, indicating the superiority of CO{sub 2} hydrate to the ice. In addition, the experiments also revealed that the size of the CO{sub 2} hydrate particles had a significant effect on the performance of flame extinction. 5 refs., 2 tabs., 7 figs.

  5. Life cycle study. Carbon dioxide emissions lower in electric heating than in oil heating

    Energy Technology Data Exchange (ETDEWEB)

    Heikkinen, A.; Jaervinen, P.; Nikula, A.

    1996-11-01

    A primary objective of energy conservation is to cut carbon dioxide emissions. A comparative study on the various heating forms, based on the life cycle approach, showed that the carbon dioxide emissions resulting form heating are appreciably lower now that electric heating has become more common. The level of carbon dioxide emissions in Finland would have been millions of tonnes higher had oil heating been chosen instead of electric heating. (orig.)

  6. Utilisation of flue gases from biofuels in greenhouses as carbon dioxide source

    International Nuclear Information System (INIS)

    Kuopanportti, H.; Rissanen, R.; Vuollet, A.; Kanniainen, T.; Tikka, A.; Ramm-Chmidt, L.; Seppaelae, R.; Piira, T.

    2006-01-01

    The objectives of the project is to develop technologies by which the flue gases from burning bio fuels and peat can be purified for used in green houses as a low cost source of carbon dioxide. Traditionally carbon dioxide has been produced by burning propane or natural gas or by injecting bottled carbon dioxide gas directly into the green house. The new methods should be more affordable than the present ones. (orig.)

  7. Process systems engineering issues and applications towards reducing carbon dioxide emissions through conversion technologies

    DEFF Research Database (Denmark)

    Roh, Kosan; Frauzem, Rebecca; Gani, Rafiqul

    2016-01-01

    This paper reviews issues and applications for design of sustainable carbon dioxide conversion processes, specifically through chemical conversion, and the integration of the conversion processes with other systems from a process systems engineering (PSE) view-point. Systematic and computer......-aided methods and tools for reaction network generation, processing route generation, process design/optimization, and sustainability analysis are reviewed with respect to carbon dioxide conversion. Also, the relevant gaps and opportunities are highlighted. In addition, the integration of carbon dioxide...

  8. The use of the carbon dioxide laser in head and neck lymphangioma.

    Science.gov (United States)

    White, B; Adkins, W Y

    1986-01-01

    The carbon dioxide laser has been used to treat various lesions of the head and neck, ranging from carcinomas to hemangiomas, and even including tatoos. A search of the literature does not reveal any reports of the carbon dioxide laser being used to treat lymphangioma. This report discusses the efficacy of treating lymphangioma of the air and food passages with the carbon dioxide laser, and presents three patients who have been treated in this fashion-two for palliation and one for cure.

  9. Carbon Dioxide Sequestering Using Microalgal Systems

    Energy Technology Data Exchange (ETDEWEB)

    Daniel J. Stepan; Richard E. Shockey; Thomas A. Moe; Ryan Dorn

    2002-02-01

    This project evaluated key design criteria, the technical feasibility, and the preliminary economic viability of a CO{sub 2}-sequestering system integrated with a coal-fired power plant based on microalgae biofixation. A review of relevant literature was conducted, and a bench-scale algal-based sequestration system was constructed and operated to verify algal growth capabilities using a simulated flue gas stream. The bench-scale system was a 20-gallon glass aquarium with a 16-gallon operating volume and was direct-sparged with a simulated flue gas. The flue gas composition was based on flue gas analyses for a 550-MW Coal Creek Power Station boiler in Underwood, North Dakota, which averaged 12.1% CO{sub 2}, 5.5% O{sub 2}, 423 ppm SO{sub 2}, 124 ppm NO{sub x}, and an estimated 50 mg/m{sup 3} fly ash loading. The algae were grown in Bold's basal growth medium. Lighting was provided using a two-tube fluorescent ''grow-light'' bulb fixture mounted directly above the tank. Algal growth appeared to be inhibited in the presence of SO{sub 2} using mixed cultures of green and blue-green cultures of algae. Samples of Monoraphidium strain MONOR02 and Nannochloropsis NANNO02 algal samples were obtained from the University of Hawaii Culture Collection. These samples did not exhibit inhibited growth in the presence of all the simulated flue gas constituents, but growth rates were somewhat lower than those expected, based on the review of literature. Samples of harvested algae were analyzed for protein, lipid, and carbohydrate content. A lipid content of 26% appeared to be fairly normal for algae, and it did not appear that large amounts of nitrogen were being fixed and promoting growth, nor were the algae starved for nitrogen. Proteins made up 41% of the total mass, and carbohydrates were assumed to be 33% (by difference). A preliminary economic analysis showed the costs of an integrated system based on microalgae biofixation to sequester 25% of the CO

  10. Sterilization of Lung Matrices by Supercritical Carbon Dioxide.

    Science.gov (United States)

    Balestrini, Jenna L; Liu, Angela; Gard, Ashley L; Huie, Janet; Blatt, Kelly M S; Schwan, Jonas; Zhao, Liping; Broekelmann, Tom J; Mecham, Robert P; Wilcox, Elise C; Niklason, Laura E

    2016-03-01

    Lung engineering is a potential alternative to transplantation for patients with end-stage pulmonary failure. Two challenges critical to the successful development of an engineered lung developed from a decellularized scaffold include (i) the suppression of resident infectious bioburden in the lung matrix, and (ii) the ability to sterilize decellularized tissues while preserving the essential biological and mechanical features intact. To date, the majority of lungs are sterilized using high concentrations of peracetic acid (PAA) resulting in extracellular matrix (ECM) depletion. These mechanically altered tissues have little to no storage potential. In this study, we report a sterilizing technique using supercritical carbon dioxide (ScCO2) that can achieve a sterility assurance level 10(-6) in decellularized lung matrix. The effects of ScCO2 treatment on the histological, mechanical, and biochemical properties of the sterile decellularized lung were evaluated and compared with those of freshly decellularized lung matrix and with PAA-treated acellular lung. Exposure of the decellularized tissue to ScCO2 did not significantly alter tissue architecture, ECM content or organization (glycosaminoglycans, elastin, collagen, and laminin), observations of cell engraftment, or mechanical integrity of the tissue. Furthermore, these attributes of lung matrix did not change after 6 months in sterile buffer following sterilization with ScCO2, indicating that ScCO2 produces a matrix that is stable during storage. The current study's results indicate that ScCO2 can be used to sterilize acellular lung tissue while simultaneously preserving key biological components required for the function of the scaffold for regenerative medicine purposes.

  11. Carbon Dioxide Leaser For The Treatment Of Keloids

    Directory of Open Access Journals (Sweden)

    Verma Kaushal K

    2002-01-01

    Full Text Available Keloids are difficult to treat medically or surgically. Carbon dioxide (CO2 laser is considered to be a better therapeutic option due to less chances of recurrence with this modality. Fourteen patients, 4 males and 10 females, between 9 and 36 years of age having keloids for 1 to 10 years were included in this study. The lesions were present on chest, ear lobes, nape of neck, forearm, arm and shoulder. CO2 laser with a power setting of 10 to 20 watts was used in continuous mode to vaporize/excise the lesions. The patients were followed up at the end of last week, 2nd week and then every 4 weeks for 3 months to evaluate the response to treatment. Twelve patients followed up regularly and completed this study. Six patients with keliods on chest had 50 to 70% response. Remaining 6 patients with keliods on chest had 50 to 70% response. Remaining 6 patients with lesions on the ear lobes (3, showed 50 to 90% response. Nape of neck (1, shoulder, arm and forearm (2 lesions had 50 to 90% response. In all, except one patient the healing started by 4 weeks and complete healing of the treatment area occurred within 8 weeks. Four patients with poor response to CO2 laser alone were given in addition intralesional triaminolone acetonide 40mg/ml, which resulted in a better response in these patients. One patient had depigmentation of the treated area. There were no side effects in other patients. We therefore conclude that CO2 laser is a good therapeutic modality for the treatment of keloids: however recurrence on long term follow up needs to be observed.

  12. Lidar detection of carbon dioxide in volcanic plumes

    Science.gov (United States)

    Fiorani, Luca; Santoro, Simone; Parracino, Stefano; Maio, Giovanni; Del Franco, Mario; Aiuppa, Alessandro

    2015-06-01

    Volcanic gases give information on magmatic processes. In particular, anomalous releases of carbon dioxide precede volcanic eruptions. Up to now, this gas has been measured in volcanic plumes with conventional measurements that imply the severe risks of local sampling and can last many hours. For these reasons and for the great advantages of laser sensing, the thorough development of volcanic lidar has been undertaken at the Diagnostics and Metrology Laboratory (UTAPRAD-DIM) of the Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA). In fact, lidar profiling allows one to scan remotely volcanic plumes in a fast and continuous way, and with high spatial and temporal resolution. Two differential absorption lidar instruments will be presented in this paper: BILLI (BrIdge voLcanic LIdar), based on injection seeded Nd:YAG laser, double grating dye laser, difference frequency mixing (DFM) and optical parametric amplifier (OPA), and VULLI (VULcamed Lidar), based on injection seeded Nd:YAG laser and optical parametric oscillator (OPO). The first one is funded by the ERC (European Research Council) project BRIDGE and the second one by the ERDF (European Regional Development Fund) project VULCAMED. While VULLI has not yet been tested in a volcanic site, BILLI scanned the gas emitted by Pozzuoli Solfatara (Campi Flegrei volcanic area, Naples, Italy) during a field campaign carried out from 13 to 17 October 2014. Carbon dioxide concentration maps were retrieved remotely in few minutes in the crater area. Lidar measurements were in good agreement with well-established techniques, based on different operating principles. To our knowledge, it is the first time that carbon dioxide in a volcanic plume is retrieved by lidar, representing the first direct measurement of this kind ever performed on an active volcano and showing the high potential of laser remote sensing in geophysical research.

  13. Oxygen Recovery via Carbon Dioxide Electrolysis with Microtubular Solid Oxide Cells

    Data.gov (United States)

    National Aeronautics and Space Administration — Carbon dioxide reduction is considered a major shortcoming for the current Atmosphere Revitalization System. Novel technologies are desired so that the oxygen...

  14. Removal of carbon dioxide in reprocessing spent nuclear fuel off gas by adsorption

    International Nuclear Information System (INIS)

    Fukumatsu, Teruki; Munakata, Kenzo; Tanaka, Kenji; Yamatsuki, Satoshi; Nishikawa, Masabumi

    1998-01-01

    The off gas produced by reprocessing spent nuclear fuel includes various radioactivities and these nuclei should be removed. In particular, 14 C mainly released as the form of carbon dioxide is one of the most required gaseous radioactivities to be removed because it has long a half-life. One of the methods to remove gaseous nuclei is the use of adsorption technique. The off gas contains water vapor which influences adsorption process of carbon dioxide. In this report, behavior of adsorption of carbon dioxide on various adsorbent and influence on adsorption behavior of carbon dioxide by containing water vapor are discussed. (author)

  15. Dehydrogenation of Ethylbenzene with Carbon Dioxide as Soft Oxidant over Supported Vanadium-Antimony Oxide Catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Do Young; Vislovskiy, Vladislav P.; Yoo, Jin S.; Chang, Jong San [Korea Research Institute of Chemical Technology, Daejeon (Korea, Republic of); Park, Sang Eon [Inha University, Incheon (Korea, Republic of); Park, Min Seok [Mongolia International University, Ulaanbaatar (Mongolia)

    2005-11-15

    This work presents that carbon dioxide, which is a main contributor to the global warming effect, could be utilized as a selective oxidant in the oxidative dehydrogenation of ethylbenzene. The dehydrogenation of ethylbenzene over alumina-supported vanadium-antimony oxide catalyst has been studied under different atmospheres such as inert nitrogen, steam, oxygen or carbon dioxide as diluent or oxidant. Among them, the addition of carbon dioxide gave the highest styrene yield (up to 82%) and styrene selectivity (up to 97%) along with stable activity. Carbon dioxide could play a beneficial role of a selective oxidant in the improvement of the catalytic behavior through the oxidative pathway.

  16. Carbon dioxide elimination and regeneration of resources in a microwave plasma torch.

    Science.gov (United States)

    Uhm, Han S; Kwak, Hyoung S; Hong, Yong C

    2016-04-01

    Carbon dioxide gas as a working gas produces a stable plasma-torch by making use of 2.45 GHz microwaves. The temperature of the torch flame is measured by making use of optical spectroscopy and a thermocouple device. Two distinctive regions are exhibited, a bright, whitish region of a high-temperature zone and a bluish, dimmer region of a relatively low-temperature zone. The bright, whitish region is a typical torch based on plasma species where an analytical investigation indicates dissociation of a substantial fraction of carbon dioxide molecules, forming carbon monoxides and oxygen atoms. The emission profiles of the oxygen atoms and the carbon monoxide molecules confirm the theoretical predictions of carbon dioxide disintegration in the torch. Various hydrocarbon materials may be introduced into the carbon dioxide torch, regenerating new resources and reducing carbon dioxide concentration in the torch. As an example, coal powders in the carbon dioxide torch are converted into carbon monoxide according to the reaction of CO2 + C → 2CO, reducing a substantial amount of carbon dioxide concentration in the torch. In this regards, the microwave plasma torch may be one of the best ways of converting the carbon dioxides into useful new materials. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Carbon dioxide and water vapor high temperature electrolysis

    Science.gov (United States)

    Isenberg, Arnold O.; Verostko, Charles E.

    1989-01-01

    The design, fabrication, breadboard testing, and the data base obtained for solid oxide electrolysis systems that have applications for planetary manned missions and habitats are reviewed. The breadboard tested contains sixteen tubular cells in a closely packed bundle for the electrolysis of carbon dioxide and water vapor. The discussion covers energy requirements, volume, weight, and operational characteristics related to the measurement of the reactant and product gas compositions, temperature distribution along the electrolyzer tubular cells and through the bundle, and thermal energy losses. The reliability of individual cell performance in the bundle configuration is assessed.

  18. Extraction of heavy oil by supercritical carbon dioxide

    DEFF Research Database (Denmark)

    Rudyk, Svetlana Nikolayevna; Spirov, Pavel; Søgaard, Erik Gydesen

    2010-01-01

    The present study deals with the extraction of heavy oil by supercritical carbon dioxide at the pressure values changing from 16 to 56 MPa at the fixed value of temperature: 60oC. The amount of the recovered liquid phase of oil was calculated as a percentage of the extracted amount to the initial...... 40 gm of oil. The noticeable breackover point in the graph of the oil recovery versus pressure was observed at 27 MPa, which was in concordance with the conclusions from chromatographic analysis of the extracted oil samples. But the recovery rate of 14 % at this pressure value was not high enough...

  19. Atlas of high resolution infrared spectra of carbon dioxide

    Science.gov (United States)

    Rinsland, C. P.; Benner, D. C.; Devi, V. M.; Ferry, P. S.; Sutton, C. H.; Richardson, D. J.

    1984-01-01

    A long path, low pressure laboratory spectrum of carbon dioxide is presented for the spectral region 1830 to 2010/cm. The data were recorded at 0.01/cm resolution and room temperature with the Fourier transform spectrometer in the McMath solar telescope complex at Kitt Peak National Observatory. A list of positions and assignments is given for the 1038 lines observed in this region. A total of 30 bands and subbands of 12C1602, 13C1602, 12C160180, 12C160170, and 13C160180 were observed. Previously announced in STAR as N83-19598

  20. Utilization of Ethanolamine as Carbon Dioxide Absorber For

    OpenAIRE

    Yusuf, Asdiana Irma; Zakir, Muhammad; Maming, Maming

    2015-01-01

    Utilization of ethanolamine as carbon dioxide absober for estimating of coral age from langkai island via LSC (Liquid Scintillation Counting) method has been done. Focus is to analyze coral reefs taken from Langkai island surface which is relatively far from the influence of human activities. Chemical preparation was carried out by using a mixture of NaOH with H2O2 30% followed by a mixture of HClO4 with H2O2 30%, and finally with HCl solution to produce a clean sample with 8.6% weight reduct...

  1. New and future developments in catalysis activation of carbon dioxide

    CERN Document Server

    Suib, Steven L

    2013-01-01

    New and Future Developments in Catalysis is a package of books that compile the latest ideas concerning alternate and renewable energy sources and the role that catalysis plays in converting new renewable feedstock into biofuels and biochemicals. Both homogeneous and heterogeneous catalysts and catalytic processes will be discussed in a unified and comprehensive approach. There will be extensive cross-referencing within all volumes. This volume presents a complete picture of all carbon dioxide (CO2) sources, outlines the environmental concerns regarding CO2, and critica

  2. Monthly, global emissions of carbon dioxide from fossil fuel consumption

    DEFF Research Database (Denmark)

    Andres, R.J.; Gregg, Jay Sterling; Losey, L.

    2011-01-01

    This paper examines available data, develops a strategy and presents a monthly, global time series of fossil-fuel carbon dioxide emissions for the years 1950–2006. This monthly time series was constructed from detailed study of monthly data from the 21 countries that account for approximately 80......% of global total emissions. These data were then used in a Monte Carlo approach to proxy for all remaining countries. The proportional-proxy methodology estimates by fuel group the fraction of annual emissions emitted in each country and month. Emissions from solid, liquid and gas fuels are explicitly...

  3. Carbon dioxide from fossil fuels. Adapting to uncertainty

    Energy Technology Data Exchange (ETDEWEB)

    Chen, K; Winter, R C; Bergman, M K

    1980-12-01

    The world is likely to experience noticeable carbon dioxide induced global warming by the beginning of the next century if high annual growth rates of fossil fuel energy use continue. This article proposes some ideas about what can be done from a policy-making perspective if the CO$SUB$2 effects occur, and how, in addition, we can deal now with the uncertainties. It also considers questions concerning the potential for control of CO$SUB$2 emissions drawing up on current work in long range coal-based energy technology assessment. (70 refs.)

  4. Carbon dioxide and climate: too much heat clouds debate

    Energy Technology Data Exchange (ETDEWEB)

    Gribben, J

    1978-12-01

    Technical feature:The possibility of a significant global warming as a result of increased atmospheric carbon dioxide from the burning of fossil fuels (the greenhouse effect) has recently received attention from climatologists and energy policy planners. The greenhouse effect has been used by the pro-nuclear lobby as an argument in favor of a massive commitment to nuclear power generation. While the CO2 problem is real, the solution does not lie in an energy strategy based on nuclear power, which involves as yet unsolved problems of radioactive waste disposal. The economic feasibility of processes for removing CO2 from waste gases should be investigated. (4 graphs, 10 references)

  5. Optical performance of the Gemini carbon dioxide laser fusion system

    International Nuclear Information System (INIS)

    Viswanathan, V.K.; Hayden, J.J.; Liberman, I.

    1979-01-01

    The performance of the Gemini two beam carbon dioxide laser fusion system was recently upgraded by installation of optical components with improved quality in the final amplifier. A theoretical analysis was conducted in conjunction with measurements of the new performance. The analysis and experimental procedures, and results obtained are reported and compared. Good agreement was found which was within the uncertainties of the analysis and the inaccuracies of the experiments. The focal spot Strehl ratio was between 0.24 and 0.3 for both beams

  6. A Review of Carbon Dioxide Selective Membranes: A Topical Report

    Energy Technology Data Exchange (ETDEWEB)

    Dushyant Shekhawat; David R. Luebke; Henry W. Pennline

    2003-12-01

    Carbon dioxide selective membranes provide a viable energy-saving alternative for CO2 separation, since membranes do not require any phase transformation. This review examines various CO2 selective membranes for the separation of CO2 and N2, CO2 and CH4, and CO2 and H2 from flue or fuel gas. This review attempts to summarize recent significant advances reported in the literature about various CO2 selective membranes, their stability, the effect of different parameters on the performance of the membrane, the structure and permeation properties relationships, and the transport mechanism applied in different CO2 selective membranes.

  7. Renewable methane generation from carbon dioxide and sunlight

    Energy Technology Data Exchange (ETDEWEB)

    Steinlechner, Christoph; Junge, Henrik [Leibniz Institut fuer Katalyse, Universitaet Rostock e.V., Rostock (Germany)

    2018-01-02

    The direct approach: Methane is a potential key player in the world's transition to a more sustainable energy future. The direct conversion of carbon dioxide into methane is highly desirable to lower the concentration of CO{sub 2} in the atmosphere and also to store renewable energy. This Highlight describes the first homogeneous system for the light-driven conversion of CO{sub 2} into CH{sub 4}. (copyright 2018 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. Carbon dioxide and methane fluxes from arctic mudboils

    International Nuclear Information System (INIS)

    Wilson, K.S.; Humphreys, E.R.

    2010-01-01

    Carbon-rich ecosystems in the Arctic have large stores of soil carbon. However, small changes in climate have the potential to change the carbon (C) balance. This study examined how changes in ecosystem structure relate to differences in the exchange of greenhouse gases, notably carbon dioxide (CO 2 ) and methane (CH 4 ), between the atmosphere and soil. In particular, it examined low-center mudboils to determine the influence that this distinct form of patterned ground in the Arctic may have on the overall C balance of Tundra ecosystems. The net ecosystem exchange of carbon dioxide (NEE) was measured along with methane efflux along a 35-m transect intersecting two mudboils in a wet sedge fen in Canada's Southern Arctic during the summer of 2008. Mudboil features revealed significant variations in vegetation, soil temperature and thaw depth, and soil organic matter content along this transect. Variations in NEE were attributed to changes in the amount of vascular vegetation, but CO 2 and CH 4 effluxes were similar among the two mudboil and the sedge fen sampling areas. The study showed that vegetation played a key role in limiting temporal variations in CH 4 effluxes through plant mediated transport in both mudboil and sedge fen sampling areas. The negligible vascular plant colonization in one of the mudboils was likely due to more active frost heave processes. Growth and decomposition of cryptogamic organisms along with inflow of dissolved organic C and warmer soil temperatures may have been the cause of the rather high CO 2 and CH 4 efflux in this mudboil area.

  9. Electrochemical Membrane for Carbon Dioxide Capture and Power Generation

    Energy Technology Data Exchange (ETDEWEB)

    Ghezel-Ayagh, Hossein [FuelCell Energy, Inc., Danbury, CT (United States)

    2017-12-21

    FuelCell Energy, Inc. (FCE), in collaboration with AECOM Corporation (formerly URS Corporation) and Pacific Northwest National Laboratory, has been developing a novel Combined Electric Power and Carbon-dioxide Separation (CEPACS) system. The CEPACS system is based on electrochemical membrane (ECM) technology derived from FCE’s carbonate fuel cell products featuring internal (methane steam) reforming and carrying the trade name of Direct FuelCell®. The unique chemistry of carbonate fuel cells offers an innovative approach for separation of CO2 from existing fossil-fuel power plant exhaust streams (flue gases). The ECM-based CEPACS system has the potential to become a transformational CO2-separation technology by working as two devices in one: it separates the CO2 from the exhaust of other plants such as an existing coal-fired plant and simultaneously produces clean electric power at high efficiency using a supplementary fuel. The development effort was carried out under the U.S. Department of Energy (DOE) cooperative agreement DE-FE0007634. The overall objective of this project was to successfully demonstrate the ability of FCE’s ECM-based CEPACS system technology to separate ≥90% of the CO2 from a simulated Pulverized Coal (PC) power plant flue gas stream and to compress the captured CO2 to a state that can be easily transported for sequestration or beneficial use. In addition, a key objective was to show, through the technical and economic feasibility study and bench scale testing, that the ECM-based CEPACS system is an economical alternative for CO2 capture in PC power plants, and that it meets DOE’s objective related to the incremental cost of electricity (COE) for post-combustion CO2 capture (no more than 35% increase in COE). The project was performed in three budget periods (BP). The specific objective for BP1 was to complete the Preliminary Technical and Economic Feasibility Study

  10. Electron irradiation of carbon dioxide-carbon disulphide ice analog ...

    Indian Academy of Sciences (India)

    les and the reactions where they take part in making the complex molecules were studied in laboratory simu- lations in both the gas and ice phase.1 Indeed, in such experimental simulations it is observed that several other carbon and sulphur bearing molecules, so far not reported to be present in the ISM, were also synthe-.

  11. Modeling seasonal changes of atmospheric carbon dioxide and carbon 13

    International Nuclear Information System (INIS)

    Gillette, D.A.; Box, E.O.

    1986-01-01

    A two-dimensional (latitude-altitude) model of atmospheric CO 2 and δ 13 C was constructed to simulate some features of seasonal carbon cycle fluctuations. The model simulates air-sea exchange, atmospheric diffusion, and fossil fuel carbon sources, which are functions of time and latitude. In addition, it uses biosphere-atmosphere fluxes of carbon that are based on global-scale biological models of vegetation growth and decay. Results of the model show fair agreement with observational results for CO 2 and δ 13 C seasonal fluctuations. Their model results have far northern fluctuations with smaller amplitudes than are observed. Analysis of sources of CO 2 change at given latitudes shows that, for far southern latitudes, southern hemisphere biospheric fluxes are dominant in affecting the seasonal CO 2 fluctuations. Long-term decrease of δ 13 C for the model is larger than for observations. This may be due to errors in the formulation for oceanic fluxes for 13 C in the model or to a net uptake of carbon by the biosphere

  12. Recycling Carbon Dioxide into Sustainable Hydrocarbon Fuels: Electrolysis of Carbon Dioxide and Water

    Science.gov (United States)

    Graves, Christopher Ronald

    Great quantities of hydrocarbon fuels will be needed for the foreseeable future, even if electricity based energy carriers begin to partially replace liquid hydrocarbons in the transportation sector. Fossil fuels and biomass are the most common feedstocks for production of hydrocarbon fuels. However, using renewable or nuclear energy, carbon dioxide and water can be recycled into sustainable hydrocarbon fuels in non-biological processes which remove oxygen from CO2 and H2O (the reverse of fuel combustion). Capture of CO2 from the atmosphere would enable a closed-loop carbon-neutral fuel cycle. The purpose of this work was to develop critical components of a system that recycles CO2 into liquid hydrocarbon fuels. The concept is examined at several scales, beginning with a broad scope analysis of large-scale sustainable energy systems and ultimately studying electrolysis of CO 2 and H2O in high temperature solid oxide cells as the heart of the energy conversion, in the form of three experimental studies. The contributions of these studies include discoveries about electrochemistry and materials that could significantly improve the overall energy use and economics of the CO2-to-fuels system. The broad scale study begins by assessing the sustainability and practicality of the various energy carriers that could replace petroleum-derived hydrocarbon fuels, including other hydrocarbons, hydrogen, and storage of electricity on-board vehicles in batteries, ultracapacitors, and flywheels. Any energy carrier can store the energy of any energy source. This sets the context for CO2 recycling -- sustainable energy sources like solar and wind power can be used to provide the most energy-dense, convenient fuels which can be readily used in the existing infrastructure. The many ways to recycle CO2 into hydrocarbons, based on thermolysis, thermochemical loops, electrolysis, and photoelectrolysis of CO2 and/or H 2O, are critically reviewed. A process based on high temperature co

  13. Sulfur dioxide leaching of spent zinc-carbon-battery scrap

    Energy Technology Data Exchange (ETDEWEB)

    Avraamides, J.; Senanayake, G.; Clegg, R. [A.J. Parker Cooperative Research Centre for Hydrometallurgy, Murdoch University, Perth, WA 6150 (Australia)

    2006-09-22

    Zinc-carbon batteries, which contain around 20% zinc, 35% manganese oxides and 10% steel, are currently disposed after use as land fill or reprocessed to recover metals or oxides. Crushed material is subjected to magnetic separation followed by hydrometallurgical treatment of the non-magnetic material to recover zinc metal and manganese oxides. The leaching with 2M sulfuric acid in the presence of hydrogen peroxide recovers 93% Zn and 82% Mn at 25{sup o}C. Alkaline leaching with 6M NaOH recovers 80% zinc. The present study shows that over 90% zinc and manganese can be leached in 20-30min at 30{sup o}C using 0.1-1.0M sulfuric acid in the presence of sulfur dioxide. The iron extraction is sensitive to both acid concentration and sulfur dioxide flow rate. The effect of reagent concentration and particle size on the extraction of zinc, manganese and iron are reported. It is shown that the iron and manganese leaching follow a shrinking core kinetic model due to the formation of insoluble metal salts/oxides on the solid surface. This is supported by (i) the decrease in iron and manganese extraction from synthetic Fe(III)-Mn(IV)-Zn(II) oxide mixtures with increase in acid concentration from 1M to 2M, and (ii) the low iron dissolution and re-precipitation of dissolved manganese and zinc during prolonged leaching of battery scrap with low sulfur dioxide. (author)

  14. Geological storage of carbon dioxide: the role of sedimentary basins

    International Nuclear Information System (INIS)

    Gunter, W.D.; Bachu, S.

    2001-01-01

    Sedimentary basins, occuring throughout the world, are thick piles of geologically deposited sediments that are the hosts for fossil fuel deposits. They may become even more important in the future if their large storage capacity is utilized for disposing of carbon dioxide. Sedimentary basins are dynamic, in the sense that they have an intricate plumbing system defined by the location of high and low permeability strata that control the flow of fluids throughout the basins and define 'hydrogeological' traps. The most secure type of hydrogeological trapping is found in oil and gas reservoirs in the form of 'structural' or 'stratigraphic' traps, termed 'closed' hydrogeological traps which have held oil and gas for millions of years. Obviously, these would be very attractive for CO 2 storage due to their long history of containment. A second type of hydrogeological trapping has been recognized in aquifers of sedimentary basins that have slow flow rates. The pore space in such 'open' hydrogeological traps is usually filled with saline ground or formation water. A volume of CO 2 injected into a deep open hydrogeological trap can take over a million years to travel updip to reach the surface and be released to the atmosphere. Although the capacity of structural/stratigraphic traps for CO 2 storage is small relative to open hydrogeological traps in deep sedimentary basins, they are likely to be used first as they are known to be secure, having held oil and gas for geological time. As the capacity of closed traps is exhausted and more is learned about geochemical trapping, the large storage capacity available in open hydrogeological traps will be utilized where security of the geological storage of CO 2 can be enhanced by geochemical reactions of the CO 2 with basic silicate minerals to form carbonates. Potential short circuits to the surface through faults or abandoned wells must be located and their stability evaluated before injection of CO 2 . In any event, a

  15. The carbon-nitrogen balance of the nodule and its regulation under elevated carbon dioxide concentration.

    Science.gov (United States)

    Libault, Marc

    2014-01-01

    Legumes have developed a unique way to interact with bacteria: in addition to preventing infection from pathogenic bacteria like any other plant, legumes also developed a mutualistic symbiotic relationship with one gender of soil bacteria: rhizobium. This interaction leads to the development of a new root organ, the nodule, where the differentiated bacteria fix for the plant the atmospheric dinitrogen (atmN2). In exchange, the symbiont will benefit from a permanent source of carbon compounds, products of the photosynthesis. The substantial amounts of fixed carbon dioxide dedicated to the symbiont imposed to the plant a tight regulation of the nodulation process to balance carbon and nitrogen incomes and outcomes. Climate change including the increase of the concentration of the atmospheric carbon dioxide is going to modify the rates of plant photosynthesis, the balance between nitrogen and carbon, and, as a consequence, the regulatory mechanisms of the nodulation process. This review focuses on the regulatory mechanisms controlling carbon/nitrogen balances in the context of legume nodulation and discusses how the change in atmospheric carbon dioxide concentration could affect nodulation efficiency.

  16. Attempts at estimating mixed venous carbon dioxide tension by the single-breath method.

    Science.gov (United States)

    Ohta, H; Takatani, O; Matsuoka, T

    1989-01-01

    The single-breath method was originally proposed by Kim et al. [1] for estimating the blood carbon dioxide tension and cardiac output. Its reliability has not been proven. The present study was undertaken, using dogs, to compare the mixed venous carbon dioxide tension (PVCO2) calculated by the single-breath method with the PVCO2 measured in mixed venous blood, and to evaluate the influence of variations in the exhalation duration and the volume of expired air usually discarded from computations as the deadspace. Among the exhalation durations of 15, 30 and 45 s tested, the 15 s duration was found to be too short to obtain an analyzable O2-CO2 curve, but at either 30 or 45 s, the calculated values of PVCO2 were comparable to the measured PVCO2. A significant agreement between calculated and measured PVCO2 was obtained when the expired gas with PCO2 less than 22 Torr was considered as deadspace gas.

  17. Torrefaction of corncob to produce charcoal under nitrogen and carbon dioxide atmospheres.

    Science.gov (United States)

    Li, Shu-Xian; Chen, Chang-Zhou; Li, Ming-Fei; Xiao, Xiao

    2018-02-01

    Corncob was torrefied under nitrogen and carbon dioxide atmospheres at 220-300 °C, obtaining solid products with mass yields of 69.38-95.03% and 67.20-94.99% and higher heating values of 16.58-24.77 MJ/kg and 16.68-24.10 MJ/kg, respectively. The changes of physicochemical properties of the charcoal was evaluated by many spectroscopies, contact angle determination, and combustion test. Hemicelluloses were not detected for the torrefaction under the hard conditions. As the severity increased, C concentration raised while H and O concentrations reduced. Combustion test showed that the burnout temperature of charcoal declined with the elevation of reaction temperature, and torrefaction at a high temperature shortened the time for the whole combustion process. Base on the data, torrefaction at 260 °C under carbon dioxide was recommended for the torrefaction of corncob. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Poly(urethane–carbonate)s from Carbon Dioxide

    KAUST Repository

    Chen, Zuliang

    2017-03-09

    A one-pot, two-step protocol for the direct synthesis of polyurethanes containing few carbonate linkages through polycondensation of diamines, dihalides, and CO2 in the presence of Cs2CO3 and tetrabutylammonium bromide is described. The conditions were optimized by studying the polycondensation of CO2 with 1,6-hexanediamine and 1,4-dibromobutane as model monomers. Then, various diamines and dihalides were tested under optimal conditions. Miscellaneous samples of such carbonate-containing polyurethanes exhibiting molar masses from 6000 to 22 000 g/mol (GPC) and yields higher than 85% were obtained. The thermal properties of such polyurethanes were unveiled by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA): they were found very similar to those of traditional polyurethanes obtained by diisocyanates + diols polycondensation.

  19. Poly(urethane–carbonate)s from Carbon Dioxide

    KAUST Repository

    Chen, Zuliang; Hadjichristidis, Nikolaos; Feng, Xiaoshuang; Gnanou, Yves

    2017-01-01

    A one-pot, two-step protocol for the direct synthesis of polyurethanes containing few carbonate linkages through polycondensation of diamines, dihalides, and CO2 in the presence of Cs2CO3 and tetrabutylammonium bromide is described. The conditions were optimized by studying the polycondensation of CO2 with 1,6-hexanediamine and 1,4-dibromobutane as model monomers. Then, various diamines and dihalides were tested under optimal conditions. Miscellaneous samples of such carbonate-containing polyurethanes exhibiting molar masses from 6000 to 22 000 g/mol (GPC) and yields higher than 85% were obtained. The thermal properties of such polyurethanes were unveiled by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA): they were found very similar to those of traditional polyurethanes obtained by diisocyanates + diols polycondensation.

  20. Potential reduction of carbon dioxide emissions from the use of electric energy storage on a power generation unit/organic Rankine system

    International Nuclear Information System (INIS)

    Mago, Pedro J.; Luck, Rogelio

    2017-01-01

    Highlights: • A power generation organic Rankine cycle with electric energy storage is evaluated. • The potential carbon dioxide emissions reduction of the system is evaluated. • The system performance is evaluated for a building in different climate zones. • The system emissions and cost are compared with those of conventional systems. • Use of carbon emissions cap and trade programs on the system is evaluated. - Abstract: This paper evaluates the potential carbon dioxide emissions reduction from the implementation of electric energy storage to a combined power generation unit and an organic Rankine cycle relative to a conventional system that uses utility gas for heating and utility electricity for electricity needs. Results indicate that carbon dioxide emission reductions from the operation of the proposed system are directly correlated to the ratio of the carbon dioxide emission conversion factor for electricity to that of the fuel. The location where the system is installed also has a strong influence on the potential of the proposed system to save carbon dioxide emissions. Finally, it is shown that by using carbon emissions cap and trade programs, it is possible to establish a frame of reference to compare/exchange operational cost gains with carbon dioxide emission reductions/gains.