WorldWideScience

Sample records for carbon dioxide co2

  1. Carbon dioxide (CO2) angiography in children

    International Nuclear Information System (INIS)

    Background. When iodinated contrast material is contraindicated, carbon dioxide (CO2) gas can be injected intravascularly to produce high-quality digital subtraction angiograms. Objective. CO2 angiography, although previously described in adults, has never before been reported in children. Materials and methods. We present three children with renal transplants who required renal angiography. Because of elevated creatinine levels, iodinated contrast was not used to search for possible renal artery stenosis. Instead, CO2 angiography was used to evaluate the renal artery anastomosis. Results. In all three cases, the renal artery anastomosis was clearly visualized using CO2 angiography and showed no evidence of renal artery stenosis. Conclusion. Digital CO2 angiography is an effective method for pediatric renal angiography. The technique can easily be adapted for virtually any angiographic laboratory capable of digital subtraction imaging. Digital CO2 angiography also lacks the risks of a conventional iodinated contrast medium, namely nephrotoxicity, allergic reaction and volume overload. (orig.). With 1 fig

  2. Carbon Dioxide Laser Absorption Spectrometer (CO2LAS) Aircraft Measurements of CO2

    Science.gov (United States)

    Christensen, Lance E.; Spiers, Gary D.; Menzies, Robert T.; Jacob, Joseph C.; Hyon, Jason

    2011-01-01

    The Jet Propulsion Laboratory Carbon Dioxide Laser Absorption Spectrometer (CO2LAS) utilizes Integrated Path Differential Absorption (IPDA) at 2.05 microns to obtain CO2 column mixing ratios weighted heavily in the boundary layer. CO2LAS employs a coherent detection receiver and continuous-wave Th:Ho:YLF laser transmitters with output powers around 100 milliwatts. An offset frequency-locking scheme coupled to an absolute frequency reference enables the frequencies of the online and offline lasers to be held to within 200 kHz of desired values. We describe results from 2009 field campaigns when CO2LAS flew on the Twin Otter. We also describe spectroscopic studies aimed at uncovering potential biases in lidar CO2 retrievals at 2.05 microns.

  3. Agreement of Mixed Venous Carbon Dioxide Tension (PvCO2) and Transcutaneous Carbon Dioxide (PtCO2) Measurements in Ventilated Infants

    OpenAIRE

    Uslu, Sinan; Bulbul, Ali; Dursun, Mesut; Zubarioglu, Umut; Turkoglu, Ebru; Guran, Omer

    2015-01-01

    Background: Noninvasive transcutaneous carbon dioxide monitoring has been shown to be accurate in infants and children, limited data are available to show the usefulness and limitations of partial transcutaneous carbon dioxide tension (PtCO2) value. Objectives: The current study prospectively determines the effectiveness and accuracy of PtCO2 measurements in newborns. Materials and Methods: Venous blood gas sampling and monitoring of the PtCO2 level (TCM TOSCA, Radiometer) were done simultane...

  4. Sequestration of carbon dioxide (CO2) using red mud.

    Science.gov (United States)

    Yadav, Vishwajeet S; Prasad, Murari; Khan, Jeeshan; Amritphale, S S; Singh, M; Raju, C B

    2010-04-15

    Red mud, an aluminium industry hazardous waste, has been reported to be an inexpensive and effective adsorbent. In the present work applicability of red mud for the sequestration of green house gases with reference to carbon dioxide has been studied. Red mud sample was separated into three different size fractions (RM I, RM II, RM III) of varying densities (1.5-2.2 g cm(-3)). Carbonation of each fraction of red mud was carried out separately at room temperature using a stainless steel reaction chamber at a fixed pressure of 3.5 bar. Effects of reaction time (0.5-12 h) and liquid to solid ratio (0.2-0.6) were studied for carbonation of red mud. Different instrumental techniques such as X-ray diffraction, FTIR and scanning electron microscope (SEM) were used to ascertain the different mineral phases before and after carbonation of each fraction of red mud. Characterization studies revealed the presence of boehmite, cancrinite, chantalite, hematite, gibbsite, anatase, rutile and quartz. Calcium bearing mineral phases (cancrinite and chantalite) were found responsible for carbonation of red mud. Maximum carbonation was observed for the fraction RM II having higher concentration of cancrinite. The carbonation capacity is evaluated to be 5.3 g of CO(2)/100 g of RM II. PMID:20036053

  5. Sequestration of carbon dioxide (CO2) using red mud

    International Nuclear Information System (INIS)

    Red mud, an aluminium industry hazardous waste, has been reported to be an inexpensive and effective adsorbent. In the present work applicability of red mud for the sequestration of green house gases with reference to carbon dioxide has been studied. Red mud sample was separated into three different size fractions (RM I, RM II, RM III) of varying densities (1.5-2.2 g cm-3). Carbonation of each fraction of red mud was carried out separately at room temperature using a stainless steel reaction chamber at a fixed pressure of 3.5 bar. Effects of reaction time (0.5-12 h) and liquid to solid ratio (0.2-0.6) were studied for carbonation of red mud. Different instrumental techniques such as X-ray diffraction, FTIR and scanning electron microscope (SEM) were used to ascertain the different mineral phases before and after carbonation of each fraction of red mud. Characterization studies revealed the presence of boehmite, cancrinite, chantalite, hematite, gibbsite, anatase, rutile and quartz. Calcium bearing mineral phases (cancrinite and chantalite) were found responsible for carbonation of red mud. Maximum carbonation was observed for the fraction RM II having higher concentration of cancrinite. The carbonation capacity is evaluated to be 5.3 g of CO2/100 g of RM II.

  6. Calcium and chemical looping technology for power generation and carbon dioxide (CO2) capture solid oxygen- and CO2-carriers

    CERN Document Server

    Fennell, Paul

    2015-01-01

    Calcium and Chemical Looping Technology for Power Generation and Carbon Dioxide (CO2) Capture reviews the fundamental principles, systems, oxygen carriers, and carbon dioxide carriers relevant to chemical looping and combustion. Chapters review the market development, economics, and deployment of these systems, also providing detailed information on the variety of materials and processes that will help to shape the future of CO2 capture ready power plants. Reviews the fundamental principles, systems, oxygen carriers, and carbon dioxide carriers relevant to calcium and chemical loopingProvi

  7. Atmospheric CO2 capture by algae: Negative carbon dioxide emission path.

    Science.gov (United States)

    Moreira, Diana; Pires, José C M

    2016-09-01

    Carbon dioxide is one of the most important greenhouse gas, which concentration increase in the atmosphere is associated to climate change and global warming. Besides CO2 capture in large emission point sources, the capture of this pollutant from atmosphere may be required due to significant contribution of diffuse sources. The technologies that remove CO2 from atmosphere (creating a negative balance of CO2) are called negative emission technologies. Bioenergy with Carbon Capture and Storage may play an important role for CO2 mitigation. It represents the combination of bioenergy production and carbon capture and storage, keeping carbon dioxide in geological reservoirs. Algae have a high potential as the source of biomass, as they present high photosynthetic efficiencies and high biomass yields. Their biomass has a wide range of applications, which can improve the economic viability of the process. Thus, this paper aims to assess the atmospheric CO2 capture by algal cultures. PMID:27005790

  8. 76 FR 56982 - Announcement of Federal Underground Injection Control (UIC) Class VI Program for Carbon Dioxide (CO2

    Science.gov (United States)

    2011-09-15

    ... (UIC) Class VI Program for Carbon Dioxide (CO 2 ) Geologic Sequestration (GS) Wells AGENCY... establishment of a Federal Underground Injection Control (UIC) Class VI Program for Carbon Dioxide (CO 2... Safe Drinking Water Act (SDWA) for underground injection of CO 2 for the purpose of GS (75 FR...

  9. Environmental Remediation and Conversion of Carbon Dioxide (CO2) into Useful Green Products by Accelerated Carbonation Technology

    OpenAIRE

    Kwang-Suk You; Ji-Whan Ahn; Gi-Chun Han; Mihee Lim

    2010-01-01

    This paper reviews the application of carbonation technology to the environmental industry as a way of reducing carbon dioxide (CO2), a green house gas, including the presentation of related projects of our research group. An alternative technology to very slow natural carbonation is the co-called ‘accelerated carbonation’, which completes its fast reaction within few hours by using pure CO2. Carbonation technology is widely applied to solidify or stabilize solid combustion residues from muni...

  10. 78 FR 23524 - Approval and Promulgation of Implementation Plans; North Carolina: Deferral of Carbon Dioxide (CO2

    Science.gov (United States)

    2013-04-19

    ... Carbon Dioxide (CO 2 ) Emissions From Prevention of Significant Deterioration (PSD) Requirements for... applicability to biogenic carbon dioxide (CO 2 ) emissions from bioenergy and other biogenic stationary sources... Significant Deterioration (PSD) and Title V Programs,'' Final Rule, 76 FR 43490, (July 20, 2011)...

  11. 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)

    Carbon dioxide (CO2) has been detected on the surface of several icy moons of Jupiter and Saturn via observation of the ν3 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 CO2 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 (H2O)-carbon dioxide (CO2) (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 ν3 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.

  12. CO2 (carbon dioxide) fixation by applying new chemical absorption-precipitation methods

    International Nuclear Information System (INIS)

    CO2 (carbon dioxide) is the most common greenhouse gas and most of it is emitted from human activities. The methods for CO2 emission reduction can be divided into physical, chemical, and biochemical methods. Among the physical and chemical methods, CCS (carbon capture and storage) is a well-known reducing technology. However, this method has many disadvantages including the required storage area. In general, CCS requires capture and storage processes. In this study, we propose a method for reusing the absorbed CO2 either in nature or in industry. The emitted CO2 was converted into CO32− using a conversion solution, and then made into a carbonate by combining the conversion solution with metal ions at normal temperature and pressure. The resulting carbonate was analyzed using FT-IR (Fourier transform infrared spectroscopy) and XRD (X-ray diffraction). We verified the formation of a solid consisting of calcite and vaterite. In addition, the conversion solution that was used could be reused in the same process of CCS technology. Our study demonstrates a successful method of reducing and reusing emitted CO2, thereby making CO2 a potential future resource. - Highlights: • This study focused on a new CO2 fixation process method. • In CCS technology, the desorption process requires high thermal energy consumption. • This new method does not require a desorption process because the CO2 is accomplished through CaCO3 crystallization. • A new absorption method is possible instead of the conventional absorption-desorption process. • This is not only a rapid reaction for fixing CO2, but also economically feasible

  13. Inventory of Carbon Dioxide (CO2) Emissions at Pacific Northwest National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Judd, Kathleen S.; Kora, Angela R.; Shankle, Steve A.; Fowler, Kimberly M.

    2009-06-29

    The Carbon Management Strategic Initiative (CMSI) is a lab-wide initiative to position the Pacific Northwest National Laboratory (PNNL) as a leader in science, technology and policy analysis required to understand, mitigate and adapt to global climate change as a nation. As part of an effort to walk the talk in the field of carbon management, PNNL conducted its first carbon dioxide (CO2) emissions inventory for the 2007 calendar year. The goal of this preliminary inventory is to provide PNNL staff and management with a sense for the relative impact different activities at PNNL have on the lab’s total carbon footprint.

  14. Environmental Remediation and Conversion of Carbon Dioxide (CO2 into Useful Green Products by Accelerated Carbonation Technology

    Directory of Open Access Journals (Sweden)

    Kwang-Suk You

    2010-01-01

    Full Text Available This paper reviews the application of carbonation technology to the environmental industry as a way of reducing carbon dioxide (CO2, a green house gas, including the presentation of related projects of our research group. An alternative technology to very slow natural carbonation is the co-called ‘accelerated carbonation’, which completes its fast reaction within few hours by using pure CO2. Carbonation technology is widely applied to solidify or stabilize solid combustion residues from municipal solid wastes, paper mill wastes, etc. and contaminated soils, and to manufacture precipitated calcium carbonate (PCC. Carbonated products can be utilized as aggregates in the concrete industry and as alkaline fillers in the paper (or recycled paper making industry. The quantity of captured CO2 in carbonated products can be evaluated by measuring mass loss of heated samples by thermo-gravimetric (TG analysis. The industrial carbonation technology could contribute to both reduction of CO2 emissions and environmental remediation.

  15. 75 FR 77229 - Federal Requirements Under the Underground Injection Control (UIC) Program for Carbon Dioxide (CO2

    Science.gov (United States)

    2010-12-10

    ... Control (UIC) Program for Carbon Dioxide (CO ) Geologic Sequestration (GS) Wells; Final Rule #0;#0;Federal... Underground Injection Control (UIC) Program for Carbon Dioxide (CO 2 ) Geologic Sequestration (GS) Wells... Federal requirements under the Safe Drinking Water Act (SDWA) for underground injection of carbon...

  16. Making carbon dioxide sequestration feasible: Toward federal regulation of CO2 sequestration pipelines

    International Nuclear Information System (INIS)

    As the United States moves closer to a national climate change policy, it will have to focus on a variety of factors affecting the manner in which the country moves toward a future with a substantially lower carbon footprint. In addition to encouraging renewable energy, smart grid, clean fuels and other technologies, the United States will need to make substantial infrastructure investments in a variety of industries. Among the significant contributors to the current carbon footprint in the United States is the use of coal as a major fuel for the generation of electricity. One of the most important technologies that the United States can employ to reduce its carbon footprint is to sequester the carbon dioxide ('CO2') from coal-fired power plants. This article focuses on the legal and policy issues surrounding a critical piece of the necessary sequestration infrastructure: CO2 pipelines that will carry CO2 from where it is removed from fuel or waste gas streams to where it will be sequestered. Ultimately, this article recommends developing a federally regulated CO2 pipeline program to foster the implementation of carbon sequestration technology.

  17. The effect of transcutaneous application of carbon dioxide (CO2) on skeletal muscle

    International Nuclear Information System (INIS)

    Highlights: → PGC-1α is up-regulated as a result of exercise such as mitochondrial biogenesis and muscle fiber-type switching, and up-regulation of VEGF. → We demonstrated transcutaneous application of CO2 up-regulated the gene expression of PGC-1α, SIRT1 and VEGF, and instance of muscle fiber switching. → Transcutaneous application of CO2 may cause similar effect to aerobic exercise in skeletal muscle. -- Abstract: In Europe, carbon dioxide therapy has been used for cardiac disease and skin problems for a long time. However there have been few reports investigating the effects of carbon dioxide therapy on skeletal muscle. Peroxisome proliferators-activated receptor (PPAR)-gamma coactivator-1 (PGC-1α) is up-regulated as a result of exercise and mediates known responses to exercise, such as mitochondrial biogenesis and muscle fiber-type switching, and neovascularization via up-regulation of vascular endothelial growth factor (VEGF). It is also known that silent mating type information regulation 2 homologs 1 (SIRT1) enhances PGC-1α-mediated muscle fiber-type switching. Previously, we demonstrated transcutaneous application of CO2 increased blood flow and a partial increase of O2 pressure in the local tissue known as the Bohr effect. In this study, we transcutaneously applied CO2 to the lower limbs of rats, and investigated the effect on the fast muscle, tibialis anterior (TA) muscle. The transcutaneous CO2 application caused: (1) the gene expression of PGC-1α, silent mating type information regulation 2 homologs 1 (SIRT1) and VEGF, and increased the number of mitochondria, as proven by real-time PCR and immunohistochemistry, (2) muscle fiber switching in the TA muscle, as proven by isolation of myosin heavy chain and ATPase staining. Our results suggest the transcutaneous application of CO2 may have therapeutic potential for muscular strength recovery resulting from disuse atrophy in post-operative patients and the elderly population.

  18. Photopromoted carbonylation of olefins with carbon dioxide and labelling studies with 13CO2 and 13CH3OH

    Institute of Scientific and Technical Information of China (English)

    YIN Jingmei; GAO Dabin; HU Jiehan; ZHOU Guangyun; JIA Yingping; WANG Xiangsheng

    2003-01-01

    Photopromoted carbonylation of olefins with carbon dioxide can be completed in ambient conditions (room temperatures and atmospheric pressure) by Co(OAc)2 catalysis. It was found that in carbonyl carbons of methyl ester of aliphatic acid 50% is from CO2 and the other 50% from CH3OH by labelling experimental with 13CO2 and 13CH3OH.

  19. Supercritical carbon dioxide (SC-CO2) as a clean technology for palm kernel oil extraction

    OpenAIRE

    Norhuda I; Jusoff K

    2009-01-01

    Efforts towards application of Supercritical Carbon Dioxide (SCCO2) extraction in Malaysia are still at its infancy stage. More research has actively on-going to explore its potential performance on a bigger scale (industrial scale) so that it will provide a better alternative method of extraction compare to the present practice using organic solvent extraction. SC-CO2 has been proven on laboratory and pilot-scale as an effective extraction technique for large types of bio-materials such as h...

  20. Carbon dioxide sequestration by mineral carbonation. Feasibility of enhanced natural weathering as a CO2 emission reduction technology

    International Nuclear Information System (INIS)

    A possible technology that can contribute to the reduction of carbon dioxide emissions is CO2 sequestration by mineral carbonation. The basic concept behind mineral CO2 sequestration is the mimicking of natural weathering processes in which calcium or magnesium containing minerals react with gaseous CO2 and form solid calcium or magnesium carbonates. Potential advantages of mineral CO2 sequestration compared to, e.g., geological CO2 storage include (1) the permanent and inherently safe sequestration of CO2, due to the thermodynamic stability of the carbonate product formed and (2) the vast potential sequestration capacity, because of the widespread and abundant occurrence of suitable feedstock. In addition, carbonation is an exothermic process, which potentially limits the overall energy consumption and costs of CO2 emission reduction. However, weathering processes are slow, with timescales at natural conditions of thousands to millions of years. For industrial implementation, a reduction of the reaction time to the order of minutes has to be achieved by developing alternative process routes. The aim of this thesis is an investigation of the technical, energetic, and economic feasibility of CO2 sequestration by mineral carbonation. In Chapter 1 the literature published on CO2 sequestration by mineral carbonation is reviewed. Among the potentially suitable mineral feedstock for mineral CO2 sequestration, Ca-silicates, more particularly wollastonite (CaSiO3), a mineral ore, and steel slag, an industrial alkaline solid residue, are selected for further research. Alkaline Ca-rich residues seem particularly promising, since these materials are inexpensive and available near large industrial point sources of CO2. In addition, residues tend to react relatively rapidly with CO2 due to their (geo)chemical instability. Various process routes have been proposed for mineral carbonation, which often include a pre-treatment of the solid feedstock (e.g., size reduction and

  1. Performance assessment of carbonation process integrated with coal fired power plant to reduce CO2 (carbon dioxide) emissions

    International Nuclear Information System (INIS)

    This paper presents a novel approach to recover energy from mineral carbonation process, one of the CCS (carbon capture and storage) technologies, to reduce its additional energy demand and reports the feasibility of integrating a carbonation process with an existing power plant for reducing CO2 (carbon dioxide) emission. A thermodynamic mass and energy flow model of the carbonation process is developed using Matlab/Simulink software for a range of carbonation temperatures using two naturally available feedstocks, namely serpentine and olivine. The CO2 emissions are reduced if a carbonation system is implemented in the power plant, though the power generation efficiency and net power output are reduced too due to the large amount of extra energy required for the grinding of feedstock and the compression of CO2. The existing power plant efficiency was found to be 36.1%. If a carbonation system is incorporated, the plant efficiency reduces to 22% and 24% using serpentine and olivine feedstocks respectively. However, a significant amount of heat energy can be recovered from exothermic reaction of carbonation and carbonated products. The power plant efficiency can be increased to 35% and 34% again, respectively, when energy from carbonation reaction and carbonated products can be recovered appropriately. - Highlights: • Mineral carbonation technology is one of the carbon capture and storage technologies. • Exothermic heat energy can be recovered from mineral carbonation process. • Mineral carbonation process is energy self-sufficient. • Thermodynamic mass and energy balance model is developed for mineral carbonation

  2. Coal and energy security for India: Role of carbon dioxide (CO2) capture and storage (CCS)

    International Nuclear Information System (INIS)

    Coal is the abundant domestic energy resource in India and is projected to remain so in future under a business-as-usual scenario. Using domestic coal mitigates national energy security risks. However coal use exacerbates global climate change. Under a strict climate change regime, coal use is projected to decline in future. However this would increase imports of energy sources like natural gas (NG) and nuclear and consequent energy security risks for India. The paper shows that carbon dioxide (CO2) capture and storage (CCS) can mitigate CO2 emissions from coal-based large point source (LPS) clusters and therefore would play a key role in mitigating both energy security risks for India and global climate change risks. This paper estimates future CO2 emission projections from LPS in India, identifies the potential CO2 storage types at aggregate level and matches the two into the future using Asia-Pacific Integrated Model (AIM/Local model) with a Geographical Information System (GIS) interface. The paper argues that clustering LPS that are close to potential storage sites could provide reasonable economic opportunities for CCS in future if storage sites of different types are further explored and found to have adequate capacity. The paper also indicates possible LPS locations to utilize CCS opportunities economically in future, especially since India is projected to add over 220,000 MW of thermal power generation capacity by 2030.

  3. Accounting for behavioral effects of increases in the carbon dioxide (CO2) tax in revenue estimation in Sweden

    International Nuclear Information System (INIS)

    In this paper we describe how behavioral responses of carbon dioxide (CO2) tax increases are accounted for in tax revenue estimation in Sweden. The rationale for developing a method for this is a mix between that a CO2 tax is a primary climate policy tool aiming to reduce CO2 emissions and that the CO2 tax generates sizable tax revenues. - Highlights: → We develop a method on the long run tax revenue effects of increasing the CO2 tax in Sweden. → We use long run price elasticities as the basis for calculating the long run effects. → The CO2 tax is the primary instrument to reduce CO2 emissions from sectors outside the EU ETS. → There is almost an exact correlation between fossil energy use and fossil CO2 emissions. → The method provide consistent estimates of emission reductions following from CO2 tax increases.

  4. Carbon dioxide sequestration: Modeling the diffusive and convective transport under a CO2 cap

    KAUST Repository

    Allen, Rebecca

    2012-01-01

    A rise in carbon dioxide levels from industrial emissions is contributing to the greenhouse effect and global warming. CO2 sequestration in saline aquifers is a strategy to reduce atmospheric CO2 levels. Scientists and researchers rely on numerical simulators to predict CO2 storage by modeling the fluid transport behaviour. Studies have shown that after CO2 is injected into a saline aquifer, undissolved CO2 rises due to buoyant forces and will spread laterally away from the injection site under an area of low permeability. CO2 from this ‘capped\\' region diffuses into the fluid underlying it, and the resulting CO2-fluid mixture increases in density. This increase in density leads to gravity-driven convection. Accordingly, diffusive-convective transport is important to model since it predicts an enhanced storage capacity of the saline aquifer. This work incorporates the diffusive and convective transport processes into the transport modeling equation, and uses a self-generated code. Discretization of the domain is done with a cell-centered finite difference method. Cases are set up using similar parameters from published literature in order to compare results. Enhanced storage capacity is predicted in this work, similar to work done by others. A difference in the onset of convective transport between this work and published results is noticed and discussed in this paper. A sensitivity analysis is performed on the density model used in this work, and on the diffusivity value assumed. The analysis shows that the density model and diffusivity value is a key component on simulation results. Also, perturbations are added to porosity and permeability in order to see the effect of perturbations on the onset of convection, and results agree with similar findings by others. This work provides a basis for studying other cases, such as the impact of heterogeneity on the diffusion-convective transport. An extension of this work may involve the use of an equation of state to

  5. Surface chemistry of CO2 - Adsorption of carbon dioxide on clean surfaces at ultrahigh vacuum

    Science.gov (United States)

    Burghaus, Uwe

    2014-05-01

    Carbon dioxide chemistry has attracted significant interest in recent years. Although the field is diverse, a current and more comprehensive review of the surface science literature may be of interest for a variety of communities since environmental chemistry, energy technology, materials science, catalysis, and nanocatalysis are certainly affected by gas-surface properties. The review describes surface phenomena and characterization strategies highlighting similarities and differences, instead of providing only a list of system-specific information. The various systems are roughly distinguished as those that clearly form carbonates and those that merely physisorb CO2 at ultra-high vacuum conditions. Nevertheless, extended sections about specific systems including rarely studied surfaces and unusual materials are included, making this review also useful as a reference.

  6. Thermodynamic analysis of gas – steam combined cycle with carbon dioxide (CO2 emissions saving

    Directory of Open Access Journals (Sweden)

    Alka Gupta, Om Prakash, S.K. Shukla

    2011-03-01

    Full Text Available In this paper, cogeneration or combined heat and power (CHP cycle has been analyzed in order to improve the efficiency of the gas – steam combined cycle and utilization of waste heat. The efficiency of the combined cycle is improved by decreasing the compressor inlet temperature (CIT and increasing the turbine inlet temperature (TIT. It is observed that the cycle offers the advantage of making efficient use of the energy available in the fuel and in turn, eliminate some portion of pollution associated with the power generation. The study also reveals that if this cycle is being employed for cogeneration, there is a significant saving (11.60% in the amount of Carbon dioxide (CO2 emitted by the coal-fired thermal power plants.

  7. The Effect of Carbon Dioxide (CO2) Laser on Sandblasting with Large Grit and Acid Etching (SLA) Surface

    OpenAIRE

    Foroutan, Tahereh; Ayoubian, Nader

    2013-01-01

    Introduction: The purpose of this study was to investigate the effect of 6W power Carbon Dioxide Laser (CO2) on the biologic compatibility of the Sandblasting with large grit and acid etching (SLA) titanium discs through studying of the Sarcoma Osteogenic (SaOS-2) human osteoblast-like cells viability.

  8. Up-Scaling Geochemical Reaction Rates for Carbon Dioxide (CO2) in Deep Saline Aquifers

    Energy Technology Data Exchange (ETDEWEB)

    Peters, Catherine A

    2013-02-28

    Geochemical reactions in deep subsurface environments are complicated by the consolidated nature and mineralogical complexity of sedimentary rocks. Understanding the kinetics of these reactions is critical to our ability to make long-term predictions about subsurface processes such as pH buffering, alteration in rock structure, permeability changes, and formation of secondary precipitates. In this project, we used a combination of experiments and numerical simulation to bridge the gap between our knowledge of these reactions at the lab scale and rates that are meaningful for modeling reactive transport at core scales. The focus is on acid-driven mineral dissolution, which is specifically relevant in the context of CO2-water-rock interactions in geological sequestration of carbon dioxide. The project led to major findings in three areas. First, we modeled reactive transport in pore-network systems to investigate scaling effects in geochemical reaction rates. We found significant scaling effects when CO2 concentrations are high and reaction rates are fast. These findings indicate that the increased acidity associated with geological sequestration can generate conditions for which proper scaling tools are yet to be developed. Second, we used mathematical modeling to investigate the extent to which SO2, if co-injected with CO2, would acidify formation brines. We found that there exist realistic conditions in which the impact on brine acidity will be limited due to diffusion rate-limited SO2 dissolution from the CO2 phase, and the subsequent pH shift may also be limited by the lack of availability of oxidants to produce sulfuric acid. Third, for three Viking sandstones (Alberta sedimentary basin, Canada), we employed backscattered electron microscopy and energy dispersive X-ray spectroscopy to statistically characterize mineral contact with pore space. We determined that for reactive minerals in sedimentary consolidated rocks, abundance alone is not a good predictor of

  9. Stabilization of carbon dioxide (CO2) bubbles in micrometer-diameter aqueous droplets and the formation of hollow microparticles.

    Science.gov (United States)

    Lu, Tianyi; Fan, Rong; Delgadillo, Luis F; Wan, Jiandi

    2016-04-26

    We report an approach to stabilize carbon dioxide (CO2) gas bubbles encapsulated in micrometer-diameter aqueous drops when water in the aqueous drops is evaporated. CO2-in-water-in-oil double emulsion drops are generated using microfluidic approaches and evaporation is conducted in the presence of sodium dodecyl sulfate (SDS), poly(vinyl alcohol) (PVA) and/or graphene oxide (GO) particles dispersed in the aqueous phase of the double emulsion drops. We examine the roles of the bubble-to-drop size ratio, PVA and GO concentration in the stabilization of CO2 bubbles upon water evaporation and show that thin-shell particles with encapsulated CO2 bubbles can be obtained under optimized conditions. The developed approach offers a new strategy to study CO2 dissolution and stability on the microscale and the synthesis of novel gas-core microparticles. PMID:27025654

  10. Integrated Energy System with Beneficial Carbon Dioxide (CO2) Use - Final Scientific/Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Xiaolei; Rink, Nancy T

    2011-04-29

    This report presents an integrated energy system that combines the production of substitute natural gas through coal hydrogasification with an algae process for beneficial carbon dioxide (CO2) use and biofuel production (funded under Department of Energy (DOE) contract DE-FE0001099). The project planned to develop, test, operate and evaluate a 2 ton-per-day coal hydrogasification plant and 25-acre algae farm at the Arizona Public Service (APS) 1000 Megawatt (MW) Cholla coal-fired power plant in Joseph City, Arizona. Conceptual design of the integrated system was undertaken with APS partners Air Liquide (AL) and Parsons. The process engineering was separated into five major areas: flue gas preparation and CO2 delivery, algae farming, water management, hydrogasification, and biofuel production. The process flow diagrams, energy and material balances, and preliminary major equipment needs for each major area were prepared to reflect integrated process considerations and site infrastructure design basis. The total project also included research and development on a bench-scale hydrogasifier, one-dimensional (1-D) kinetic-model simulation, extensive algae stressing, oil extraction, lipid analysis and a half-acre algae farm demonstration at APS?s Redhawk testing facility. During the project, a two-acre algae testing facility with a half-acre algae cultivation area was built at the APS Redhawk 1000 MW natural gas combined cycle power plant located 55 miles west of Phoenix. The test site integrated flue gas delivery, CO2 capture and distribution, algae cultivation, algae nursery, algae harvesting, dewatering and onsite storage as well as water treatment. The site environmental, engineering, and biological parameters for the cultivators were monitored remotely. Direct biodiesel production from biomass through an acid-catalyzed transesterification reaction and a supercritical methanol transesterification reaction were evaluated. The highest oil-to-biodiesel conversion of 79

  11. Supercritical carbon dioxide (SC-CO2 as a clean technology for palm kernel oil extraction

    Directory of Open Access Journals (Sweden)

    Norhuda I

    2009-04-01

    Kyoto Protocol. Keywords: By-product, Solvent extraction, Kyoto protocol, Supercritical Carbon Dioxide, Palm Kernel Oil Received: 13 July 2008 / Received in revised form: 17 February 2009, Accepted: 28 February 2009, Published online: 12 March 2009

  12. Effects of pure and impure carbon dioxide (CO2) on soil chemistry

    OpenAIRE

    Wei, Yang

    2013-01-01

    A cleaner use of fossil fuels supported by Carbon Capture and Storage (CCS) techniques is considered to be one of the main short-term strategies for addressing the global climate change problem. However, potential CO2 or CO2/SO2 seepage during some of the phases of a CCS project not only reduces its performing efficiency, but also impacts the local environment, which could have further impacts on human health. It is therefore essential to assess the potential risks and provide evidence that t...

  13. CO_2在炼钢工艺的应用及发展%Application and Development of Carbon Dioxide in the Steelmaking Process

    Institute of Scientific and Technical Information of China (English)

    朱荣; 毕秀荣; 吕明

    2012-01-01

    The emission of carbon dioxide in the iron and steelmaking process is about 16% of that in the industrial system.How to reduce the emission of carbon dioxide and take use of carbon dioxide is one of main problems that has attracted many steel engineers' attention.In order to take the utilization of carbon dioxide as a resource in steelmaking process,application of carbon dioxide as stirring gas,reaction media and protection gas was analyzed at home and abroad,and previous research on the application of carbon dioxide in steelmaking process was introduced.%钢铁生产过程CO2排放占工业CO2排放量的16%左右。如何降低CO2排放并使CO2进行资源化利用是钢铁工作者关心的重要问题。以CO2在炼钢过程中的资源化利用为出发点,分析了国内外CO2作为炼钢过程的搅拌气源、反应介质及保护气源的应用情况,并介绍了笔者在炼钢应用CO2方面所做的前期研究工作的进展。

  14. Carbonated concrete blocks for CO2 captation

    OpenAIRE

    Courard, Luc; Parmentier, Véronique; Michel, Frédéric

    2015-01-01

    The CO2 captation process called carbonation, improves specific properties of the concrete during the conversion of carbon dioxide CO2 into calcium carbonate CaCO3. Current environmental concerns motivate the study of carbonation in order to maximize the absorption of carbon dioxide. Moreover, lightweight concrete with bio-based products knows an interesting development in the construction field, especially as thermal insulation panels for walls in buildings. Concrete blocks produced with mis...

  15. Research Progress of Carbon Dioxide Capture Technology%CO2捕集技术研究

    Institute of Scientific and Technical Information of China (English)

    艾先立

    2014-01-01

    This article reveals the relationship between the concentration of CO 2 and air temperature ,and points out that carbon dioxide capture and storage is one of the effective solutions .The commonly used methods of CO2 capture include solvent absorption ,oxygen -rich combustion ,capturing CO2 from ambient air ,membrane separation and pressure swing adsorption ,etc .The article makes a comparative analysis of advantages and disadvantages of these capture methods .The results show that the absorbent is easily decomposed and the equipment is corroded by the alkaline absorbent ;the method of oxygen - rich combustion can only remove combustible impurities , and the operating costs during the preparation of oxygen are expensive ;in the process of roasting calcium carbonate need high energy efficiency ,and the air scrubbers are very large ;raw gas of membrane separation has highly purity ;pressure swing adsorption needs high pressure ,energy consumption and operating costs .At last ,the article presents the development direction of carbon dioxide capture technology .%指出了CO2浓度与温室效应之间的关系,CO2捕集是有效的解决方案之一。常用的捕集方法有:溶剂吸收法、富氧燃烧法、空气捕集、膜分离法、变压吸附(PS A )法等。分析比较了各种捕集方法的优缺点:溶剂吸收法吸收剂易被分解且再生能耗高,对设备腐蚀大;富氧燃烧法在制备氧气时能耗高,只能去除可燃性杂质;从空气中捕集CO2,浓度较低空气洗涤器规格过大,焙烧CaCO3时能耗高;膜分离法对原料气的要求较高;变压吸附法需要2次加压,能耗高,运行成本大。提出了CO2捕集技术的发展方向与建议。

  16. Proximate Composition of Seed and Biomass from Soybean Plants Grown at Different Carbon Dioxide (CO2) Concentrations

    Science.gov (United States)

    Wheeler, R. M.; Mackowiak, C. L.; Sager, J. C.

    1990-01-01

    Soybean plants were grown for 90 days at 500, 1000, 2000, and 5000 ubar (ppm) carbon dioxide (CO2) and compared for proximate nutritional value. For both cultivars (MC and PX), seed protein levels were highest at 1000 (39.3 and 41.9 percent for MC and PX) and lowest at 2000 (34.7 and 38.9 percent for MC and PX). Seed fat (oil) levels were highest at 2000 (21.2 and 20.9 percent for MC and PX) and lowest at 5000 (13.6 and 16.6 percent for MC and PX). Seed carbohydrate levels were highest at 500 (31.5 and 28.4 percent for MC and PX) and lowest at 2000 (20.9 and 20.8 percent for MC and PX). When adjusted for total seed yield per unit growing area, the highest production of protein and carbohydrate occurred with MC at 1000, while equally high amounts of fat were produced with MC at 1000 and 2000. Seed set and pod development at 2000 were delayed in comparison to other CO2 treatments; thus the proportionately high fat and low protein at 2000 may have been a result of the delay in plant maturity rather than CO2 concentration. Stem crude fiber and carbohydrate levels for both cultivars increased with increased CO2. Leaf protein and crude fiber levels also tended to rise with increased CO2 but leaf carbohydrate levels decreased as CO2 was increased. The results suggest that CO2 effects on total seed yield out-weighed any potential advantages to changes in seed composition.

  17. Transcutaneous application of carbon dioxide (CO2 induces mitochondrial apoptosis in human malignant fibrous histiocytoma in vivo.

    Directory of Open Access Journals (Sweden)

    Yasuo Onishi

    Full Text Available Mitochondria play an essential role in cellular energy metabolism and apoptosis. Previous studies have demonstrated that decreased mitochondrial biogenesis is associated with cancer progression. In mitochondrial biogenesis, peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α regulates the activities of multiple nuclear receptors and transcription factors involved in mitochondrial proliferation. Previously, we showed that overexpression of PGC-1α leads to mitochondrial proliferation and induces apoptosis in human malignant fibrous histiocytoma (MFH cells in vitro. We also demonstrated that transcutaneous application of carbon dioxide (CO(2 to rat skeletal muscle induces PGC-1α expression and causes an increase in mitochondrial proliferation. In this study, we utilized a murine model of human MFH to determine the effect of transcutaneous CO(2 exposure on PGC-1α expression, mitochondrial proliferation and cellular apoptosis. PGC-1α expression was evaluated by quantitative real-time PCR, while mitochondrial proliferation was assessed by immunofluorescence staining and the relative copy number of mitochondrial DNA (mtDNA was assessed by real-time PCR. Immunofluorescence staining and DNA fragmentation assays were used to examine mitochondrial apoptosis. We also evaluated the expression of mitochondrial apoptosis related proteins, such as caspases, cytochorome c and Bax, by immunoblot analysis. We show that transcutaneous application of CO(2 induces PGC-1α expression, and increases mitochondrial proliferation and apoptosis of tumor cells, significantly reducing tumor volume. Proteins involved in the mitochondrial apoptotic cascade, including caspase 3 and caspase 9, were elevated in CO(2 treated tumors compared to control. We also observed an enrichment of cytochrome c in the cytoplasmic fraction and Bax protein in the mitochondrial fraction of CO(2 treated tumors, highlighting the involvement of mitochondria in apoptosis

  18. Sorption of methane and CO2 for enhanced coalbed methane recovery and carbon dioxide seauestration

    Institute of Scientific and Technical Information of China (English)

    Basanta Kumar Prusty

    2008-01-01

    Sequestration of CO2 in deep and unmineable coal seams is one of the attractive alternatives to reduce its atmospheric concentration. Injection of CO2 in coal seams may help in enhancing the recovery of coalbed methane. An experimental study has been carried out using coal samples from three different coal seams, to evaluate the enhanced gas recovery and sequestration potential of these coals. The coals were first saturated with methane and then by depressurization some of the adsorbed methane was desorbed. After partial desorption, CO2 was injected into the coals and subsequently they were depressurized again. Desorption of methane after the injections was studied, to investigate the ability of CO2 to displace and enhance the recovery of methane from the coals. The coals exhibited varying behavior of adsorption of CO2 and release of methane. For one coal, the release of methane was enhanced by injection of CO2, suggesting preferential adsorption of CO2 and desorption of methane. For the other two coals, CO2 injection did not produce incremental methane initially, as there was initial resistance to methane release. However with continued CO2 injection, most of the remaining methane was produced. The study suggested that preferential sorption behavior of coal and enhanced gas recovery pattern could not be generalized for all coals.

  19. Carbon dioxide is tightly bound in the [Co(Pyridine)(CO2)]− anionic complex

    International Nuclear Information System (INIS)

    The [Co(Pyridine)(CO2)]− anionic complex was studied through the combination of photoelectron spectroscopy and density functional theory calculations. This complex was envisioned as a primitive model system for studying CO2 binding to negatively charged sites in metal organic frameworks. The vertical detachment energy (VDE) measured via the photoelectron spectrum is 2.7 eV. Our calculations imply a structure for [Co(Pyridine)(CO2)]− in which a central cobalt atom is bound to pyridine and CO2 moieties on either sides. This structure was validated by acceptable agreement between the calculated and measured VDE values. Based on our calculations, we found CO2 to be bound within the anionic complex by 1.4 eV

  20. Carbon dioxide (CO2) digital subtraction angiography for transjugular intrahepatic portsystemic shunt procedures

    International Nuclear Information System (INIS)

    Purpose: To determine the efficacy of CO2 as negative contrast medium compared with iodinated contrast medium in creation and control of TIPS. Material and Methods: CO2 was used during TIPS procedures in 33 patients. In 21 patients a wedged hepatic venography was obtained for planning the shunt tract. Additional TIPS-control DSA was performed in 42 cases by direct portal venography to verify the TIPS function and patency. In all cases CO2 gas was used in addition to iodinated contrast medium. Results: CO2 produced excellent wedged hepatic venographys in all patients. Visualisation of the portal veins and collaterals was superior to iodinated contrast medium. The TIPS-control DSA performed with CO2 were comparable to those performed with iodinated contrast medium. Complications were not observed in our study. Conclusion: CO2 is an effective contrast medium for TIPS procedures. In particular the visualisation of portal veins performed by CO2-wedged hepatic venography is superior to iodinated contrast medium. (orig.)

  1. CO2/clay interactions and the significance for geological storage of carbon dioxide

    Science.gov (United States)

    Busch, Andreas; Wentinck, Rick; Bertier, Pieter

    2015-04-01

    For the characterization of CO2 storage reservoirs a number of critical parameters need to be assessed, like storage capacity or injection rate, where a straight-forward work flow based on existing experience in the oil and gas industry is available. Added complexity is in the identification of (potential) leakage pathways along wellbores, faults/fractures or even capillary seal networks. The critical aspects are mechanisms and rates of potential leakage. Over the past few years an improved understanding of the interaction of CO2 with clay minerals was generated, with a major focus on swelling clays, such as montmorillonite. Especially in relatively young and / or low maturity sedimentary basins, smectite contents of the seal lithologies can be high (e.g. North Sea). It was found that for CO2 storage and storage containment non-negligible physical effects result from clays in contact with CO2 and water under pressure, temperature and stress conditions representative for geological reservoirs. It was shown that all clay minerals are able to adsorb significant amounts of CO2, while only smectite swells in the presence of CO2, thereby creating a swelling force that is potentially large and may affect local stress fields. Several cases where this interaction might become important are discussed in this contribution: (1) clay swelling between wellbore cement and host rock, (2) CO2 adsorption of clays in the storage reservoir, (3) clay swelling and the impact on fractures and faults, potentially acting as pathways, for fluid leakage and (4) shrinkage of swelling clays due to dehydration by CO2 and the possible creation of dehydration cracks. This contribution aims at summarizing these effects, increasing awareness and discussing its significance for the geological storage of CO2.

  2. Carbon Dioxide Capture: Covalent Organic Frameworks for CO2 Capture (Adv. Mater. 15/2016).

    Science.gov (United States)

    Zeng, Yongfei; Zou, Ruqiang; Zhao, Yanli

    2016-04-01

    Covalent organic frameworks (COFs) serve as ideal platforms that can selectively adsorb and separate CO2 from gas mixtures. On page 2855, R. Zou, Y. Zhao, and Y. Zeng highlight research progress in this area, compare recent achievements, and present fundamental principles. Different strategies to improve the CO2 capture capability of COFs are elaborated and the capture performance of representative COFs is analyzed. PMID:27075837

  3. Effect of carbon dioxide (CO2) on mortality and reproduction of Anagasta kuehniella (Zeller 1879), in mass rearing, aiming at the production of Trichogramma spp.

    Science.gov (United States)

    Coelho Junior, Aloisio; Parra, José R P

    2013-01-01

    Eggs of Anagasta kuehniella (Zeller 1879) are widely used for mass rearing of Trichogramma spp. and other parasitoids and predators, largely commercialized in many countries. The aim of this study is to evaluate the effect of carbon dioxide (CO2) originated from larval metabolism on the biological parameters of A. kuehniella. For that purpose, we assess the production of carbon dioxide (CO2) per rearing tray of A. kuehniella and the effect of CO2 on the viability of egg-to-adult period and oviposition of A. kuehniella. Results allow to estimate that a rearing tray, containing 10,000 larvae between the 4th and 5th instars, produces an average of 30.67 mL of CO2 per hour. The highest egg production of A. kuehniella was obtained when the larvae were kept in rooms with lower concentration of CO2 (1,200 parts per million - ppm), producing 23% more eggs than in rooms with higher CO2 concentrations. In rooms with high density of trays (70 trays/room), CO2 concentration exceeded 4,400 ppm. The viability of the egg-to-adult period was not influenced by carbon dioxide. PMID:23828359

  4. Carbon Dioxide (CO2) Retrievals from Atmospheric Chemistry Experiment (ACE) Solar Occultation Measurements

    Science.gov (United States)

    Rinsland, Curtis P.; Chiou, Linda; Boone, Chris; Bernath, Peter

    2010-01-01

    The Atmospheric Chemistry Experiment ACE satellite (SCISAT-1) was launched into an inclined orbit on 12 August 2003 and is now recording high signal-to-noise 0.02 per centimeter resolution solar absorption spectra covering 750-4400 per centimeter (2.3-13 micrometers). A procedure has been developed for retrieving average dry air CO2 mole fractions (X(sub CO2)) in the altitude range 7-10 kilometers from the SCISAT-1 spectra. Using the N2 continuum absorption in a window region near 2500 per centimeter, altitude shifts are applied to the tangent heights retrieved in version 2.2 SCISAT-1 processing, while cloudy or aerosol-impacted measurements are eliminated. Monthly-mean XCO2 covering 60 S to 60 N latitude for February 2004 to March 2008 has been analyzed with consistent trends inferred in both hemispheres. The ACE XCO2 time series have been compared with previously-reported surface network measurements, predictions based on upper tropospheric aircraft measurements, and space-based measurements. The retrieved X(sub CO2) from the ACE-FTS spectra are higher on average by a factor of 1.07 plus or minus 0.025 in the northern hemisphere and by a factor of 1.09 plus or minus 0.019 on average in the southern hemisphere compared to surface station measurements covering the same time span. The ACE derived trend is approximately 0.2% per year higher than measured at surface stations during the same observation period.

  5. Carbon monoxide : A quantitative tracer for fossil fuel CO2?

    NARCIS (Netherlands)

    Gamnitzer, Ulrike; Karstens, Ute; Kromer, Bernd; Neubert, Rolf E. M.; Meijer, Harro A. J.; Schroeder, Hartwig; Levin, Ingeborg

    2006-01-01

    Carbon monoxide (CO), carbon dioxide (CO2), and radiocarbon ((CO2)-C-14) measurements have been made in Heidelberg from 2001 to 2004 in order to determine the regional fossil fuel CO2 component and to investigate the application of CO as a quantitative tracer for fossil fuel CO2 (CO2(foss)). The obs

  6. Historical changes in carbon dioxide (CO2) and dimethyl sulphide (DMS) emissions in the eutrophied Southern North Sea

    Science.gov (United States)

    Gypens, N.; Borges, A. V.; Lancelot, C.

    2012-04-01

    Anthropogenic activities after the Second World War have severely increased river nutrient [nitrogen (N) and phosphorus (P)] loads to European coastal areas. The resulting N: P: Si imbalance (compared to phytoplankton requirements) stimulated in the Southern North Sea the growth of Phaeocystis colonies modifying the functioning of the ecosystem and, therefore, the carbon but also the biogenic sulphur cycles. Phaeocystis is a significant producer of DMSP (dimethylsulphide propionate), the precursor of DMS. When emitted to the atmosphere the DMS has a cooling effect on the climate contrarily to the CO2 greenhouse gas. Since the late 1990's specific nutrient reduction policies have however considerably reduced P loads while N is maintained. In this application we explore, with a mathematical tool, the effects of changing N and P loads on air-sea CO2 exchanges and DMS marine emissions. The chosen model is the MIRO-CO2-DMS, a complex biogeochemical model describing carbon, biogenic sulphur and nutrient cycles in the marine domain. Model simulations are performed for the contemporary period since 1950, using real forcing fields for sea surface temperature, wind speed and atmospheric CO2 and RIVERSTRAHLER model simulations for river carbon and nutrient loads. Results are discussing the importance of human activities and river inputs of carbon and nutrients on the eutrophication of coastal areas, their ability to absorb atmospheric CO2 and the importance of DMS emissions associated with phytoplankton blooms, especially Phaeocystis.

  7. Water-rock-CO2 interactions in saline aquifers aimed for carbon dioxide storage: Experimental and numerical modeling studies of the Rio Bonito Formation (Permian), southern Brazil

    International Nuclear Information System (INIS)

    Mineral trapping is one of the safest ways to store CO2 underground as C will be immobilized in a solid phase. Carbon dioxide will be, therefore, sequestered for geological periods of time, helping to diminish greenhouse gas emissions and mitigate global warming. Although mineral trapping is considered a fairly long process, owing to the existence of kinetic barriers for mineral precipitation, it has been demonstrated both experimentally and by numerical modeling. Here the results of experimental and numerical modeling studies performed in sandstones of the saline aquifer of the Rio Bonito Formation, Parana Basin, are presented. The Rio Bonito Formation consists of paralic sandstones deposited in the intracratonic Parana Basin, southern Brazil, during the Permian (Artinskian-Kungurian). These rocks have the largest potential for CO2 storage because of their appropriated reservoir quality, depth and proximity to the most important stationary CO2 sources in Brazil. Here it is suggested that CO2 can be permanently stored as carbonates as CO2 reacts with rocks of the Rio Bonito Formation and forms CaCO3 at temperatures and pressures similar to those encountered for CO2 storage in geological formations. Results of this work will be useful for studies of partitioning mechanisms for C trapping in CO2 storage programs.

  8. The system-wide economics of a carbon dioxide capture, utilization, and storage network: Texas Gulf Coast with pure CO2-EOR flood

    International Nuclear Information System (INIS)

    This letter compares several bounding cases for understanding the economic viability of capturing large quantities of anthropogenic CO2 from coal-fired power generators within the Electric Reliability Council of Texas electric grid and using it for pure CO2 enhanced oil recovery (EOR) in the onshore coastal region of Texas along the Gulf of Mexico. All captured CO2 in excess of that needed for EOR is sequestered in saline formations at the same geographic locations as the oil reservoirs but at a different depth. We analyze the extraction of oil from the same set of ten reservoirs within 20- and five-year time frames to describe how the scale of the carbon dioxide capture, utilization, and storage (CCUS) network changes to meet the rate of CO2 demand for oil recovery. Our analysis shows that there is a negative system-wide net present value (NPV) for all modeled scenarios. The system comes close to breakeven economics when capturing CO2 from three coal-fired power plants to produce oil via CO2-EOR over 20 years and assuming no CO2 emissions penalty. The NPV drops when we consider a larger network to produce oil more quickly (21 coal-fired generators with CO2 capture to produce 80% of the oil within five years). Upon applying a CO2 emissions penalty of 60$2009/tCO2 to fossil fuel emissions to ensure that coal-fired power plants with CO2 capture remain in baseload operation, the system economics drop significantly. We show near profitability for the cash flow of the EOR operations only; however, this situation requires relatively cheap electricity prices during operation. (letter)

  9. The system-wide economics of a carbon dioxide capture, utilization, and storage network: Texas Gulf Coast with pure CO2-EOR flood

    Science.gov (United States)

    King, Carey W.; Gülen, Gürcan; Cohen, Stuart M.; Nuñez-Lopez, Vanessa

    2013-09-01

    This letter compares several bounding cases for understanding the economic viability of capturing large quantities of anthropogenic CO2 from coal-fired power generators within the Electric Reliability Council of Texas electric grid and using it for pure CO2 enhanced oil recovery (EOR) in the onshore coastal region of Texas along the Gulf of Mexico. All captured CO2 in excess of that needed for EOR is sequestered in saline formations at the same geographic locations as the oil reservoirs but at a different depth. We analyze the extraction of oil from the same set of ten reservoirs within 20- and five-year time frames to describe how the scale of the carbon dioxide capture, utilization, and storage (CCUS) network changes to meet the rate of CO2 demand for oil recovery. Our analysis shows that there is a negative system-wide net present value (NPV) for all modeled scenarios. The system comes close to breakeven economics when capturing CO2 from three coal-fired power plants to produce oil via CO2-EOR over 20 years and assuming no CO2 emissions penalty. The NPV drops when we consider a larger network to produce oil more quickly (21 coal-fired generators with CO2 capture to produce 80% of the oil within five years). Upon applying a CO2 emissions penalty of 602009/tCO2 to fossil fuel emissions to ensure that coal-fired power plants with CO2 capture remain in baseload operation, the system economics drop significantly. We show near profitability for the cash flow of the EOR operations only; however, this situation requires relatively cheap electricity prices during operation.

  10. Regional Opportunities for Carbon Dioxide Capture and Storage in China: A Comprehensive CO2 Storage Cost Curve and Analysis of the Potential for Large Scale Carbon Dioxide Capture and Storage in the People’s Republic of China

    Energy Technology Data Exchange (ETDEWEB)

    Dahowski, Robert T.; Li, Xiaochun; Davidson, Casie L.; Wei, Ning; Dooley, James J.

    2009-12-01

    This study presents data and analysis on the potential for carbon dioxide capture and storage (CCS) technologies to deploy within China, including a survey of the CO2 source fleet and potential geologic storage capacity. The results presented here indicate that there is significant potential for CCS technologies to deploy in China at a level sufficient to deliver deep, sustained and cost-effective emissions reductions for China over the course of this century.

  11. Fiscal 1995 investigation on biological fixation of carbon dioxide; 1995 nendo seibutsuteki CO2 kotei ni kansuru chosa hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    To cope with the global warming caused by CO2, an investigation was conducted into biological fixation. It is necessary to make a many-sided and comprehensive study on the mechanism of CO2 fixation, the scale (area and carbon holding density), the rate and the environmental impact of the introduction of the technology and the technical problems, and to make a quantitative evaluation of each of the methods in order to make them practical proposals. The global ecosystem is classified into the land biota and ocean biota, and each typical ecosystem was surveyed in terms of the surface area, the carbon holding amount (presently existing amount), the net primary production amount, the required nutrient salt amount, the transpiration rate, etc. Next, a discussion was made on the increasing effect of the carbon fixation amount by changing the present ecosystem from the aspect of scale and rate. At the same time, a study was carried out of energy efficiency, economical efficiency and problems. Last, elementary technology was taken up which seems to be important for implementing measures for the biological carbon fixation. As to the ocean, it is necessary to obtain information, which is not sufficient to utilize marine biota for CO2 fixation, especially on the mechanism of depth-direction transfer of organism and its quantitative grasp. As to the land, one of the measures is conversion of the ecosystem where the amount of carbon fixed is small to the ecosystem where the amount is large. 249 refs., 58 figs., 51 tabs.

  12. Effect of Carbon dioxide (CO2 on mortality and reproduction of Anagasta kuehniella (Zeller 1879, in mass rearing, aiming at the production of Trichogramma spp.

    Directory of Open Access Journals (Sweden)

    ALOISIO COELHO JUNIOR

    2013-06-01

    Full Text Available Eggs of Anagasta kuehniella (Zeller 1879 are widely used for mass rearing of Trichogramma spp. and other parasitoids and predators, largely commercialized in many countries. The aim of this study is to evaluate the effect of carbon dioxide (CO2 originated from larval metabolism on the biological parameters of A. kuehniella. For that purpose, we assess the production of carbon dioxide (CO2 per rearing tray of A. kuehniella and the effect of CO2 on the viability of egg-to-adult period and oviposition of A. kuehniella. Results allow to estimate that a rearing tray, containing 10,000 larvae between the 4th and 5th instars, produces an average of 30.67 mL of CO2 per hour. The highest egg production of A. kuehniella was obtained when the larvae were kept in rooms with lower concentration of CO2 (1,200 parts per million - ppm, producing 23% more eggs than in rooms with higher CO2 concentrations. In rooms with high density of trays (70 trays/room, CO2 concentration exceeded 4,400 ppm. The viability of the egg-to-adult period was not influenced by carbon dioxide.Ovos de Anagasta kuehniella (Zeller, 1879 são muito utilizados para a criação massal de Trichogramma spp. e de outros parasitóides e predadores, sendo comercializados em muitos países. O objetivo deste trabalho foi avaliar o efeito do dióxido de carbono (CO2, proveniente do metabolismo larval, em parâmetros biológicos de A. kuehniella, principalmente na postura. Para que este objetivo fosse atingido, foram avaliados a produção de dióxido de carbono (CO2 por bandeja de criação de A. kuehniella e o efeito do CO2 na viabilidade do período ovo-adulto e na postura de A. kuehniella. Por meio dos resultados obtidos pôde-se estimar que uma bandeja de criação, com lagartas entre o 4° e 5° ínstares, inoculada com 10.000 lagartas produz, em média, 30,67 ml de CO2 por hora. A maior produção de ovos de A. kuehniella foi obtida quando as lagartas foram mantidas em salas com concentra

  13. Water as a Direct Hydrogen Donor in Supercritical Carbon Di-oxide: A Novel and Efficient Zn-H2O-CO2 System for Chemo selective Reduction of Nitrobenzenes to Anilines

    Institute of Scientific and Technical Information of China (English)

    JIANG Huan-Feng; DONG Yao-Sen

    2008-01-01

    An eco-friendly and cheap Zn-H2O-CO2 system was presented for chemoselective reduction of nitrobenzenes to anilines with high yields (80%-97% isolated yields) in supercritical carbon dioxide. This process brings together the very important green chemistry technologies--the use of carbon dioxide as a solvent and the use of water as a hydrogen donor.

  14. Carbon dioxide sequestration by mineral carbonation

    OpenAIRE

    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 behind mineral CO2 sequestration is the mimicking of natural weathering processes in which calcium or magnesium containing minerals react with gaseous CO2 and form solid calcium or magnesium carbonate...

  15. Modelling and simulation of CO2 (carbon dioxide) bottoming cycles for offshore oil and gas installations at design and off-design conditions

    International Nuclear Information System (INIS)

    Improved energy efficiency is an issue of increasing importance in offshore oil and gas installations. The power on offshore installations is generated by gas turbines operating in a simple cycle. There is an obvious possibility for heat recovery for further power generation from the exhaust heat. However, the limited space and weight available makes the inclusion of bottoming cycles challenging. Due to its high working pressure and thereby compact components CO2 (carbon dioxide) could be a viable solution, combining compactness and efficiency. An in-house simulation tool is used to evaluate the performance of CO2 bottoming cycles at design and off-design conditions. Both a simple recuperated single stage cycle and a more advanced dual stage system are modelled. Results from simulations show a potential for 10–11%-points increase in net plant efficiency at 100% gas turbine load. Also off-design simulations taking the variation in heat exchanger performance into account are performed showing that the bottoming cycle improves the off-design performance compared to the standard gas turbine solution. Even at 60% GT (gas turbine) load, the combined cycle with CO2 bottoming cycle can achieve up to 45% net plant efficiency, compared to 31% for only the gas turbine. - Highlights: • Modeling of CO2 bottoming cycles. • Comparison of single and dual stage CO2 bottoming cycles. • Efficiencies comparable to steam systems. • Good off-design characteristics

  16. Investigation of water and CO2 (carbon dioxide) flooding using micro-CT (micro-computed tomography) images of Berea sandstone core using finite element simulations

    International Nuclear Information System (INIS)

    The present study reports a numerical investigation of water and CO2 (carbon dioxide) flooding at the pore scale of a porous medium. We use high resolution micro-computed tomography (micro-CT) images of Berea sandstone core to obtain the pore geometry. The numerical solution used for the simulation was carried out by a finite element based software package. Level Set method is used to determine the position of the interface between two immiscible fluids when oil is displaced by water and CO2, respectively. The present formulation is validated against single-phase flow through the porous structure. It is found that, fluid flow inside the pore space takes place through preferential inlet and outlet pores. For two-phase flow, it is observed that continuous displacement of oil occurs during water flooding but CO2 is able to displace oil at certain locations in the pores. Also, the separation of flow front is observed in the case of CO2 flooding. A quantitative comparison of the results obtained in two types of flooding simulations suggests that water displaces a higher volume of oil than CO2 in the time period for which the simulations are performed.

  17. The carbon dioxide cycle

    Science.gov (United States)

    James, P.B.; Hansen, G.B.; Titus, T.N.

    2005-01-01

    The seasonal CO2 cycle on Mars refers to the exchange of carbon dioxide between dry ice in the seasonal polar caps and gaseous carbon dioxide in the atmosphere. This review focuses on breakthroughs in understanding the process involving seasonal carbon dioxide phase changes that have occurred as a result of observations by Mars Global Surveyor. ?? 2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

  18. Risk analysis of carbon dioxide and oxygen supply systems for CO2 + O2 in situ leaching project based on HAZOP analysis method

    International Nuclear Information System (INIS)

    A method of HAZOP analysis was used to carry out the risk analysis of carbon dioxide and oxygen supply systems for CO2 + O2 in situ leaching project in a uranium mine. Through identifying the potential risks which existed in equipment and operating procedures, the possible consequences were analyzed. Aimed at existing problems, corresponding suggestions and measures were put forward. These measures can make the system to be optimized and reduce the possibility of the system fault, thus ensuring the normal operation of the in situ leaching system. (authors)

  19. 全球气候变化与CO_2减排方案的探讨%On exploration for global climate changes and carbon dioxide emission-reducing scheme

    Institute of Scientific and Technical Information of China (English)

    赵洁

    2012-01-01

    The study points out the greenhouse gas mainly with carbon dioxide is the major driving factor for the global climate changes,explores the emission-reducing scheme of the carbon dioxide from the population,the Per Capita GDP,unit energy consumption and the energy carbon content,which play the role in the emission of the carbon dioxide,and considers the geological sequestration including the oil deposits,the gas layer and the deep aquifer can increase the carbon content,and indicates the reduction of the man-made carbon dioxide is the most potential way to reduce the emission of carbon dioxide.%指出以CO2为主的温室气体是全球气候变化的最主要的驱动因素,就影响CO2排放量的入口、人均GDP、单位耗能量和能源含碳量以及碳汇量等进行CO2减排方案的探讨,并认为油田、煤气层和深部含水层等地质处置方法能够有效增加CO2的碳汇量,降低CO2的人为排放量,是当前最有潜力的CO2减排途径。

  20. Carbon Dioxide Production Responsibility on the Basis of comparing in Situ and mean CO2 Atmosphere Concentration Data

    CERN Document Server

    Mavrodiev, S Cht; Vachev, B

    2008-01-01

    The method is proposed for estimation of regional CO2 and other greenhouses and pollutants production responcibility. The comparison of CO2 local emissions reduction data with world CO2 atmosphere data will permit easy to judge for overall effect in curbing not only global warming but also chemical polution.

  1. Carbon dioxide laser guidelines

    Directory of Open Access Journals (Sweden)

    Krupa Shankar D

    2009-01-01

    Full Text Available The carbon dioxide (CO 2 laser is a versatile tool that has applications in ablative lasing and caters to the needs of routine dermatological practice as well as the aesthetic, cosmetic and rejuvenation segments. This article details the basics of the laser physics as applicable to the CO 2 laser and offers guidelines for use in many of the above indications.

  2. Carbonation and CO2 uptake of concrete

    International Nuclear Information System (INIS)

    This study developed a reliable procedure to assess the carbon dioxide (CO2) uptake of concrete by carbonation during the service life of a structure and by the recycling of concrete after demolition. To generalize the amount of absorbable CO2 per unit volume of concrete, the molar concentration of carbonatable constituents in hardened cement paste was simplified as a function of the unit content of cement, and the degree of hydration of the cement paste was formulated as a function of the water-to-cement ratio. The contribution of the relative humidity, type of finishing material for the concrete surface, and the substitution level of supplementary cementitious materials to the CO2 diffusion coefficient in concrete was reflected using various correction factors. The following parameters varying with the recycling scenario were also considered: the carbonatable surface area of concrete crusher-runs and underground phenomena of the decreased CO2 diffusion coefficient and increased CO2 concentration. Based on the developed procedure, a case study was conducted for an apartment building with a principal wall system and an office building with a Rahmen system, with the aim of examining the CO2 uptake of each structural element under different exposure environments during the service life and recycling of the building. As input data necessary for the case study, data collected from actual surveys conducted in 2012 in South Korea were used, which included data on the surrounding environments, lifecycle inventory database, life expectancy of structures, and recycling activity scenario. Ultimately, the CO2 uptake of concrete during a 100-year lifecycle (life expectancy of 40 years and recycling span of 60 years) was estimated to be 15.5%–17% of the CO2 emissions from concrete production, which roughly corresponds to 18%–21% of the CO2 emissions from the production of ordinary Portland cement. - Highlights: • CO2 uptake assessment approach owing to the concrete

  3. 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 beh

  4. 我国火电行业燃用不同煤质时CO 2排放量计算∗%The calculation of carbon dioxide emissions from different kinds of coal in thermal power industry of China

    Institute of Scientific and Technical Information of China (English)

    武世福; 苏铁熊; 张培华; 马理强

    2014-01-01

    通过对火电行业CO2排放源的梳理及煤质变化对 CO2的影响,由火电行业不同煤种推算出标准煤在不同煤种下得到的CO2排放值,阐述了燃煤电厂中 CO2排放量实际计算方法,提高了火电行业计算碳排放量的可靠性和准确度,有效解决了当前火电行业CO2排放量统计、计算的困难。%Based on carbon dioxide emission source of thermal power industry and the influ-ence of coal quality changing carbon dioxide,the carbon dioxide emissions have been calculated in different types coal in thermal power industry.The actual calculation of carbon dioxide emissions from coal fired power plants have been stated.The reliability and accuracy of carbon emissions calculation has been improved in thermal power industry,which solved the problems of statistics and calculation of carbon dioxide emissions.

  5. Hydrate-based CO2 (carbon dioxide) capture from IGCC (integrated gasification combined cycle) synthesis gas using bubble method with a set of visual equipment

    International Nuclear Information System (INIS)

    The hydrate-based carbon dioxide (CO2) capture from the integrated gasification combined cycle (IGCC) synthesis gas using the bubble method is investigated with a set of visual equipment in this work. The gas bubble is created with a bubble plate on the bottom of the equipment. By the visual equipment, the hydrate formation and the hydrate shape are visually captured. With the move of the gas bubble from the bottom to the top of the reactor, gas hydrate forms firstly from the gas–liquid boundary around the bubble, then the hydrate gradually grows up and piles up in the bottom side of the bubble to form a hydrate particle. The gas hydrate shape is affected by the gas flow rate. The hydrate is acicular crystal at the low gas flow rate while the hydrate is fine sand-like crystal at the high gas flow rate. The bubble size and the gas flow rate have an obvious impact on the hydrate-based CO2 separation process. The experimental results show the gas bubble of 50 μm and the gas flow rate of 6.75 mL/min/L are ideal for CO2 capture from IGCC synthesis gas under the condition of 3.0 MPa and 274.15 K. -- Highlights: ► A set of visual equipment and bubble method are used for hydrate-based CO2 capture. ► CO2-TBAB gas hydrate formation process and shape are captured clearly. ► Gas bubble of 50 μm and gas flow rate of 6.75 mL/min/L are the optimum process.

  6. Carbon dioxide (CO2) sorption to Na-rich montmorillonite at Carbon Capture, Utilization and Storage (CCUS) P-T conditions in saline formations

    OpenAIRE

    Krukowski, Elizabeth Gayle

    2013-01-01

    Carbon capture, utilization and storage (CCUS) in confined saline aquifers in sedimentary formations has the potential to reduce the impact of fossil fuel combustion on climate change by storing CO2 in geologic formations in perpetuity. At PT conditions relevant to CCUS, CO2 is less dense than the pre-existing brine in the formation, and the more buoyant CO2 will migrate to the top of the formation where it will be in contact with cap rock. A typical cap rock is clay-rich shale, and interacti...

  7. Petrophysical laboratory invertigations of carbon dioxide storage in a subsurface saline aquifer in Ketzin/Germany within the scope of CO2SINK

    Science.gov (United States)

    Zemke, K.; Kummmerow, J.; Wandrey, M.; Co2SINK Group

    2009-04-01

    Since June of 2008 carbon dioxide has been injected into a saline aquifer at the Ketzin test site [Würdemann et al., this volume]. The food grade CO2 is injected into a sandstone zone of the Stuttgart formation at ca. 650 m depth at 35°C reservoir temperature and 62 bar reservoir pressure. With the injection of CO2 into the geological formation, chemical and physical reservoir characteristics are changed depending on pressure, temperature, fluid chemistry and rock composition. Fluid-rock interaction could comprise dissolution of non-resistant minerals in CO2-bearing pore fluids, cementing of the pore space by precipitating substances from the pore fluid, drying and disintegration of clay minerals and thus influence of the composition and activities of the deep biosphere. To testing the injection behaviour of CO2 in water saturated rock and to evaluate the geophysical signature depending on the thermodynamic conditions, flow experiments with water and CO2 have been performed on cores of the Stuttgart formation from different locations including new wells of ketzin test site. The studied core material is an unconsolidated fine-grained sandstone with porosity values from 15 to 32 %. Permeability, electrical resistivity, and sonic wave velocities and their changes with pressure, saturation and time have been studied under simulated in situ conditions. The flow experiments conducted over several weeks with brine and CO2 showed no significant changes of resistivity and velocity and a slightly decreasing permeability. Pore fluid analysis showed mobilization of clay and some other components. A main objective of the CO2Sink laboratory program is the assessment of the effect of long-term CO2 exposure on reservoir rocks to predict the long-term behaviour of geological CO2 storage. For this CO2 exposure experiments reservoir rock samples were exposed to CO2 saturated reservoir fluid in corrosion-resistant high pressure vessels under in situ temperature and pressure

  8. Ocean sequestration of carbon dioxide: modeling the deep ocean release of a dense emulsion of liquid Co2-in-water stabilized by pulverized limestone particles.

    Science.gov (United States)

    Golomb, D; Pennell, S; Ryan, D; Barry, E; Swett, P

    2007-07-01

    The release into the deep ocean of an emulsion of liquid carbon dioxide-in-seawater stabilized by fine particles of pulverized limestone (CaCO3) is modeled. The emulsion is denser than seawater, hence, it will sink deeper from the injection point, increasing the sequestration period. Also, the presence of CaCO3 will partially buffer the carbonic acid that results when the emulsion eventually disintegrates. The distance that the plume sinks depends on the density stratification of the ocean, the amount of the released emulsion, and the entrainment factor. When released into the open ocean, a plume containing the CO2 output of a 1000 MW(el) coal-fired power plant will typically sink hundreds of meters below the injection point. When released from a pipe into a valley on the continental shelf, the plume will sink about twice as far because of the limited entrainment of ambient seawater when the plume flows along the valley. A practical system is described involving a static mixer for the in situ creation of the CO2/seawater/pulverized limestone emulsion. The creation of the emulsion requires significant amounts of pulverized limestone, on the order of 0.5 tons per ton of liquid CO2. That increases the cost of ocean sequestration by about $13/ ton of CO2 sequestered. However, the additional cost may be compensated by the savings in transportation costs to greater depth, and because the release of an emulsion will not acidify the seawater around the release point. PMID:17695916

  9. Asymmetric impact of the physiological effect of carbon dioxide on hydrological responses to instantaneous negative and positive CO2 forcing

    Science.gov (United States)

    Abe, Manabu; Shiogama, Hideo; Yokohata, Tokuta; Emori, Seita; Nozawa, Toru

    2015-10-01

    We conducted sensitivity experiments using a coupled atmosphere-ocean general circulation model to examine the asymmetry between the hydrological responses to instantaneous positive and negative CO2 forcing and the impact of the CO2 physiological effects (CDPEs) on these responses. This study focuses on the fast response occurring on time scales shorter than 1 year after imposing CO2 forcing. Experiments investigating the CO2 physiological effect show that the fast response of precipitation to positive CO2 forcing is a decrease in the global and annual mean, whereas that of negative forcing is an increase the global and annual mean precipitation. The fast global precipitation response to negative forcing is stronger than the response to positive forcing. In contrast, the experiments without the CDPE reveal similar magnitudes of the fast global precipitation responses to negative and positive CO2 forcing. Significant differences in the magnitudes of the fast precipitation response due to the CDPE are found in tropical regions such as the Amazon Basin, the Maritime Continents, and tropical Africa, where C3-type plants are common. The stomatal conductance of plant leaves is decreased by both positive and negative CO2 forcing, which suppress the transpiration from the leaves. Consequently, the CDPE enhances the asymmetry of the fast precipitation responses to positive and negative CO2 forcing. The asymmetric impact of CDPE requires a careful evaluation of future hydrological changes which is constrained by paleoclimate evidence.

  10. Bench-Scale Process for Low-Cost Carbon Dioxide (CO2) Capture Using a Phase-Changing Absorbent

    Energy Technology Data Exchange (ETDEWEB)

    Westendorf, Tiffany; Caraher, Joel; Chen, Wei; Farnum, Rachael; Perry, Robert; Spiry, Irina; Wilson, Paul; Wood, Benjamin

    2015-03-31

    The objective of this project is to design and build a bench-scale process for a novel phase-changing aminosilicone-based CO2-capture solvent. The project will establish scalability and technical and economic feasibility of using a phase-changing CO2-capture absorbent for post-combustion capture of CO2 from coal-fired power plants with 90% capture efficiency and 95% CO2 purity at a cost of $40/tonne of CO2 captured by 2025 and a cost of <$10/tonne of CO2 captured by 2035. In the first budget period of this project, the bench-scale phase-changing CO2 capture process was designed using data and operating experience generated under a previous project (ARPA-e project DE-AR0000084). Sizing and specification of all major unit operations was completed, including detailed process and instrumentation diagrams. The system was designed to operate over a wide range of operating conditions to allow for exploration of the effect of process variables on CO2 capture performance.

  11. Response of a tundra ecosytem to elevated atmospheric carbon dioxide and CO2-induced climate change. Final report

    International Nuclear Information System (INIS)

    The overall objective of this research was to document current patterns of CO2 flux in selected locations of the circumpolar arctic, and to develop the information necessary to predict how these fluxes may be affected by climate change. In fulfillment of these objectives, net CO2 flux was measured at several sites on the North Slope of Alaska during the 1990-94 growing season (June-August) to determine the local and regional patterns, of seasonal CO2 exchange. In addition, net CO2 flux was measured in the Russian and Icelandic Arctic to determine if the patterns of CO2 exchange observed in Arctic Alaska were representative of the circumpolar arctic, while cold-season CO2 flux measurements were carried out during the 1993-94 winter season to determine the magnitude of CO2 efflux not accounted for by the growing season measurements. Manipulations of soil water table depth and surface temperature, which were identified from the extensive measurements as being the most important variables in determining the magnitude and direction of net CO2 exchange, were carried out during the 1993-94 growing seasons in tussock and wet sedge tundra ecosystems. Finally, measurements of CH4 flux were also measured at several of the North Slope study sites during the 1990-91 growing seasons. Measurements were made on small (e.g. 0.5 m2) plots using a portable gas-exchange system and cuvette. The sample design allowed frequent measurements of net CO2 exchange and respiration over diurnal and seasonal cycles, and a large spatial extent that incorporated both locally and regionally diverse tundra surface types. Measurements both within and between ecosystem types typically extended over soil water table depth and temperature gradients, allowing for the indirect analysis of the effects of anticipated climate change scenarios on net CO2 exchange. In situ experiments provided a direct means for testing hypotheses

  12. Estimation of the efficiency of hydrocarbon mineralization in soil by measuring CO2-emission and variations in the isotope composition of carbon dioxide

    Science.gov (United States)

    Dubrovskaya, Ekaterina; Turkovskaya, Olga

    2010-05-01

    Estimation of the efficiency of hydrocarbon mineralization in soil by measuring CO2-emission and variations in the isotope composition of carbon dioxide E. Dubrovskaya1, O. Turkovskaya1, A. Tiunov2, N. Pozdnyakova1, A. Muratova1 1 - Institute of Biochemistry and Physiology of Plants and Microorganisms, RAS, Saratov, 2 - A.N. Severtsov Institute of Ecology and Evolution, RAS, Moscow, Russian Federation Hydrocarbon mineralization in soil undergoing phytoremediation was investigated in a laboratory experiment by estimating the variation in the 13С/12С ratio in the respired СО2. Hexadecane (HD) was used as a model hydrocarbon pollutant. The polluted soil was planted with winter rye (Secale cereale) inoculated with Azospirillum brasilense strain SR80, which combines the abilities to promote plant growth and to degrade oil hydrocarbon. Each vegetated treatment was accompanied with a corresponding nonvegetated one, and uncontaminated treatments were used as controls. Emission of carbon dioxide, its isotopic composition, and the residual concentration of HD in the soil were examined after two and four weeks. At the beginning of the experiment, the CO2-emission level was higher in the uncontaminated than in the contaminated soil. After two weeks, the quantity of emitted carbon dioxide decreased by about three times and did not change significantly in all uncontaminated treatments. The presence of HD in the soil initially increased CO2 emission, but later the respiration was reduced. During the first two weeks, nonvegetated soil had the highest CO2-emission level. Subsequently, the maximum increase in respiration was recorded in the vegetated contaminated treatments. The isotope composition of plant material determines the isotope composition of soil. The soil used in our experiment had an isotopic signature typical of soils formed by C3 plants (δ13C,-22.4‰). Generally, there was no significant fractionation of the carbon isotopes of the substrates metabolized by the

  13. Increased Feeding and Nutrient Excretion of Adult Antarctic Krill, Euphausia superba, Exposed to Enhanced Carbon Dioxide (CO2)

    OpenAIRE

    Saba, Grace K.; Oscar Schofield; Joseph J Torres; Erica H Ombres; Steinberg, Deborah K.

    2012-01-01

    Ocean acidification has a wide-ranging potential for impacting the physiology and metabolism of zooplankton. Sufficiently elevated CO(2) concentrations can alter internal acid-base balance, compromising homeostatic regulation and disrupting internal systems ranging from oxygen transport to ion balance. We assessed feeding and nutrient excretion rates in natural populations of the keystone species Euphausia superba (Antarctic krill) by conducting a CO(2) perturbation experiment at ambient and ...

  14. A Quantitative Investigation of CO2 Sequestration by Mineral Carbonation

    OpenAIRE

    Mohammad, Muneer; Ehsani, Mehrdad

    2015-01-01

    Anthropogenic activities have led to a substantial increase in carbon dioxide (CO2), a greenhouse gas (GHG), contributing to heightened concerns of global warming. In the last decade alone CO2 emissions increased by 2.0 ppm/yr. globally. In the year 2009, United States and China contributed up to 43.4% of global CO2 emissions. CO2 capture and sequestration have been recognized as promising solutions to mitigate CO2 emissions from fossil fuel based power plants. Typical techniques for carbon c...

  15. Carbon monoxide: A quantitative tracer for fossil fuel CO2?

    OpenAIRE

    Gamnitzer, Ulrike; Karstens, Ute; Kromer, Bernd; Neubert, Rolf; Meijer, Harro; Schroeder, Hartwig; LEVIN Ingeborg

    2006-01-01

    Carbon monoxide (CO), carbon dioxide (CO2), and radiocarbon (14CO2) measurements have been made in Heidelberg from 2001 to 2004 in order to determine the regional fossil fuel CO2 component and to investigate the application of CO as a quantitative tracer for fossil fuel CO2 (CO2(foss)). The observations were compared with model estimates simulated with the regional transport model REMO at 0.5°x0.5° resolution in Europe for 2002. These estimates are based on two available emissions inventories...

  16. Design of a water-CO2 evaporator : adoption of a carbon dioxide heat pump to geothermal conditions

    OpenAIRE

    Mateusz Tatys

    2009-01-01

    In this thesis the utilization of CO2 heat pumps, together with low-enthalpy geothermal waters or energy of waste water, will be discussed and an attempt will be made to convince the reader that those devices can be used in a simple way to save energy and mitigate global warming. Basing on the so-called EcoCute air to water CO2 heat pump, a unit which can make use of low temperature geothermal resources, as the external lower heat source will be designed. To reach this target special atte...

  17. Ultrafast vibrational spectroscopy (2D-IR) of CO2 in ionic liquids: Carbon capture from carbon dioxide's point of view

    Science.gov (United States)

    Brinzer, Thomas; Berquist, Eric J.; Ren, Zhe; Dutta, Samrat; Johnson, Clinton A.; Krisher, Cullen S.; Lambrecht, Daniel S.; Garrett-Roe, Sean

    2015-06-01

    The CO2ν3 asymmetric stretching mode is established as a vibrational chromophore for ultrafast two-dimensional infrared (2D-IR) spectroscopic studies of local structure and dynamics in ionic liquids, which are of interest for carbon capture applications. CO2 is dissolved in a series of 1-butyl-3-methylimidazolium-based ionic liquids ([C4C1im][X], where [X]- is the anion from the series hexafluorophosphate (PF 6- ), tetrafluoroborate (BF 4- ), bis-(trifluoromethyl)sulfonylimide (Tf2N-), triflate (TfO-), trifluoroacetate (TFA-), dicyanamide (DCA-), and thiocyanate (SCN-)). In the ionic liquids studied, the ν3 center frequency is sensitive to the local solvation environment and reports on the timescales for local structural relaxation. Density functional theory calculations predict charge transfer from the anion to the CO2 and from CO2 to the cation. The charge transfer drives geometrical distortion of CO2, which in turn changes the ν3 frequency. The observed structural relaxation timescales vary by up to an order of magnitude between ionic liquids. Shoulders in the 2D-IR spectra arise from anharmonic coupling of the ν2 and ν3 normal modes of CO2. Thermal fluctuations in the ν2 population stochastically modulate the ν3 frequency and generate dynamic cross-peaks. These timescales are attributed to the breakup of ion cages that create a well-defined local environment for CO2. The results suggest that the picosecond dynamics of CO2 are gated by local diffusion of anions and cations.

  18. Assessing the potential impact of the CO2 performance ladder on the reduction of carbon dioxide emissions in the Netherlands

    NARCIS (Netherlands)

    Rietbergen, M.G.; Blok, K.

    2013-01-01

    Green public procurement is often promoted as a tool to reduce energy use and CO2 emissions in the supply chains of public entities. However, only a limited number of studies has quantitatively assessed the environmental impacts of green public procurement schemes. The aim of this paper was to asses

  19. Carbon dioxide recycling

    Science.gov (United States)

    The recycling of carbon dioxide to methanol and dimethyl ether is seen to offer a substantial route to renewable and environmentally carbon neutral fuels. One of the authors has championed the “Methanol Economy" in articles and a book. By recycling ambient CO2, the authors argue ...

  20. 水泥工业CO2减排及利用技术进展%Technical Progress of Emission-reduction and Utilization of Carbon Dioxide in Cement Industry

    Institute of Scientific and Technical Information of China (English)

    马忠诚; 汪澜

    2011-01-01

    Emission-reduction exists potentially in cement industry, which is the key industry for carbon dioxide emission. Carbonate decomposition, fuel combustion and electric power consumption, etc. Which discharge carbon dioxide in cement industry, are introduced. A series of methods for decreasing carbon dioxide emission in cement industry, such as improving energy utilization, using alternative raw materials and fuels, developing new low carbone-mission binding materials, etc. Are expounded. Finally, several technologies for recycling of carbon dioxide, such as separation, capture, storage, fixation, etc. Are suggested.%水泥工业是CO2排放的重点行业,减排潜力巨大.全面介绍了水泥生产中碳酸盐分解、燃料燃烧和电力消耗等方面CO2的排放情况;详细阐述了水泥生产中通过提高能源利用率、使用替代原燃料、开发新型低碳排放的胶凝材料等措施实现CO2减排的方法,提出了对水泥工业CO2排放实施的分离、捕集、封存、固定等回收利用技术.

  1. Therapeutic benefits of carbon dioxide (CO2) laser on single-site HPV lesions in the lower female genital tract

    Science.gov (United States)

    Urru, Giovanni; Moretti, Gianfranco

    1998-01-01

    Numerous studies have shown contradictory variable percentages of recurrent HPV lesions, after various therapies. The present study therefore evaluates the effectiveness of CO2 laser vaporization in the treatment of single-site HPV lesions of the lower female genital tract in order to confirm the conviction that physical therapy alone, in agreement with some findings reported in the literature, is capable of guaranteeing a high cure rate in selected patients. From January 1995 to June 1996, seventy- five female patients were treated with CO2 laser vaporization for single-site genital HPV lesions, some of which were associated with low-grade intra-epithelial neoplasia. The success rate after 12 months proved to be 97%. The pre-existing clinical symptoms disappeared in all the patients treated. No complication in the vaporization procedure was encountered.

  2. Effect of Oxygen Co-Injected with Carbon Dioxide on Gothic Shale Caprock-CO2-Brine Interaction during Geologic Carbon Sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Hun Bok; Um, Wooyong; Cantrell, Kirk J.

    2013-09-16

    Co-injection of oxygen, a significant component in CO2 streams produced by the oxyfuel combustion process, can cause a significant alteration of the redox state in deep geologic formations during geologic carbon sequestration. The potential impact of co-injected oxygen on the interaction between synthetic CO2-brine (0.1 M NaCl) and shale caprock (Gothic shale from the Aneth Unit in Utah) and mobilization of trace metals was investigated at ~10 MPa and ~75 °C. A range of relative volume percentages of O2 to CO2 (0, 1, 4 and 8%) were used in these experiments to address the effect of oxygen on shale-CO2-brine interaction under various conditions. Major mineral phases in Gothic shale are quartz, calcite, dolomite, montmorillonite, and pyrite. During Gothic shale-CO2-brine interaction in the presence of oxygen, pyrite oxidation occurred extensively and caused enhanced dissolution of calcite and dolomite. Pyrite oxidation and calcite dissolution subsequently resulted in the precipitation of Fe(III) oxides and gypsum (CaSO4•2H2O). In the presence of oxygen, dissolved Mn and Ni were elevated because of oxidative dissolution of pyrite. The mobility of dissolved Ba was controlled by barite (BaSO4) precipitation in the presence of oxygen. Dissolved U in the experimental brines increased to ~8–14 g/L, with concentrations being slightly higher in the absence of oxygen than in the presence of oxygen. Experimental and modeling results indicate the interaction between shale caprock and oxygen co-injected with CO2 during geologic carbon sequestration can exert significant impacts on brine pH, solubility of carbonate minerals, stability of sulfide minerals, and mobility of trace metals. The major impact of oxygen is most likely to occur in the zone near CO2 injection wells where impurity gases can accumulate. Oxygen in CO2-brine migrating away from the injection well will be continually consumed through the reactions with sulfide minerals in deep geologic formations.

  3. A Carbon Nanotube-based Sensor for CO2 Monitoring

    OpenAIRE

    Grimes, Craig A.; Ong, Keat G.

    2001-01-01

    A carbon dioxide (CO2) sensor is fabricated by depositing a thin layer of a multiwall carbon nanotube (MWNT) – silicon dioxide (SiO2) composite upon a planar inductorcapacitor resonant circuit. By tracking the resonant frequency of the sensor the complex permittivity of the coating material can be determined. It is shown that the permittivity of MWNTs changes linearly in response to CO2 concentration, enabling monitoring of ambient CO2 levels. The passive sensor is remotely monitored wit...

  4. Transcriptome-Wide Changes in Chlamydomonas reinhardtii Gene Expression Regulated by Carbon Dioxide and the CO2-Concentrating Mechanism Regulator CIA5/CCM1

    Energy Technology Data Exchange (ETDEWEB)

    Fang, W; Si, YQ; Douglass, S; Casero, D; Merchant, SS; Pellegrini, M; Ladunga, I; Liu, P; Spalding, MH

    2012-06-26

    We used RNA sequencing to query the Chlamydomonas reinhardtii transcriptome for regulation by CO2 and by the transcription regulator CIA5 (CCM1). Both CO2 and CIA5 are known to play roles in acclimation to low CO2 and in induction of an essential CO2-concentrating mechanism (CCM), but less is known about their interaction and impact on the whole transcriptome. Our comparison of the transcriptome of a wild type versus a cia5 mutant strain under three different CO2 conditions, high CO2 (5%), low CO2 (0.03 to 0.05%), and very low CO2 (< 0.02%), provided an entry into global changes in the gene expression patterns occurring in response to the interaction between CO2 and CIA5. We observed a massive impact of CIA5 and CO2 on the transcriptome, affecting almost 25% of all Chlamydomonas genes, and we discovered an array of gene clusters with distinctive expression patterns that provide insight into the regulatory interaction between CIA5 and CO2. Several individual clusters respond primarily to either CIA5 or CO2, providing access to genes regulated by one factor but decoupled from the other. Three distinct clusters clearly associated with CCM-related genes may represent a rich source of candidates for new CCM components, including a small cluster of genes encoding putative inorganic carbon transporters.

  5. Reduction of Aldehydes by Fe-H2O-CO2 System in Supercritical Carbon Dioxide

    Institute of Scientific and Technical Information of China (English)

    HUANG Xi-zhe; JIANG Huan-feng

    2008-01-01

    @@ 1 Introduction Nowadays,green chemistry has received in creased attention.The use of water and scCO2 as a solvent or reagent is an important field for organic reactions and green chemistry both in laboratory and industry[1-4]. The reduction of aldehydes to the corresponding alcohols is an important reaction in organic synthesis and an important step in the synthesis of biologically active compounds[5,6].A number of reducing systems utilized have been developed for this purpose,including H2 catalyzed by metals[7,8],NaBH4[9],and Al-MFn-H2O[10].However,all the procedures suffered from many disadvantages,such as moisture-sensitive,low chemoselectivity,presence of a pyrophoric expensive catalyst and lack of environmentally benign processes.

  6. Development of a Sorption Enhanced Steam Hydrogasification Process for In-situ Carbon Dioxide (CO2) Removal and Enhanced Synthetic Fuel Production

    OpenAIRE

    Liu, Zhongzhe

    2013-01-01

    Energy security and climate change are two common challenges in the coming decades. The demand for energy is increasing. The CO2 in the atmosphere has increased to almost 400ppm, and it is mainly from energy usage. How to deal with energy-related CO2 emissions with the increasing demand for energy is becoming more crucial. Carbon capture and sequestration during energy production is an efficient way to guarantee enough energy supply with a smaller carbon footprint. One unique techniq...

  7. Carbon isotopes in terrestrial ecosystem pools and CO2 fluxes.

    OpenAIRE

    Bowling, DR; Pataki, DE; Randerson, JT

    2008-01-01

    Stable carbon isotopes are used extensively to examine physiological, ecological, and biogeochemical processes related to ecosystem, regional, and global carbon cycles and provide information at a variety of temporal and spatial scales. Much is known about the processes that regulate the carbon isotopic composition (delta(13)C) of leaf, plant, and ecosystem carbon pools and of photosynthetic and respiratory carbon dioxide (CO(2)) fluxes. In this review, systematic patterns and mechanisms unde...

  8. Calculation of Carbon Dioxide Emissions Considering Secondary Energy Deployment Among Provinces in China%基于二次能源省际调配的中国分省CO2排放量计算

    Institute of Scientific and Technical Information of China (English)

    周曙东; 赵明正; 王传星; 李斌

    2012-01-01

    Scientific and rational calculation of carbon dioxide emissions provides the base is for setting energy saving and emission reduction targets. The existing IPCC's method to calculate carbon dioxide emissions only considered primary energy fuels, but did not consider the secondary energy deployment, which did not reflect the true situation of carbon dioxide emissions and Chinese situation. This study provided a new method to calculate carbon dioxide emissions considering secondary energy deployment, and according to this method, carbon dioxide emissions of every province were estimated based on the statistic data in 2009. The results showed that carbon dioxide emissions in traditional energy production provinces, such as Inner Mongolia and Shanxi, decreased, and those in eastern coastal provinces increased after considering the secondary energy deployment. But the CO; emission intensity in the central and western provinces were significantly higher than those in the eastern coastal provinces. Low energy efficiency, backward energy processing technology and equipment existed in the central and western provinces, which resulted in high intensity of carbon dioxide emissions. Recommendation was made to the central government to enhance investment in energy processing industry in the western provinces to improve energy processing technology, processing equipment to increase energy efficiency and to reduce carbon dioxide emissions. The secondary energy-transferred-inprovinces should provide compensation funds to secondary energy-transferred-out-provinces , and this part of the compensation funds should be used to upgrade energy industry for traditional energy production provinces in order to achieve emissions-reduction targets successfully.%节能减排目标任务的制定需要依据科学合理的CO2排放量测算.现有的IPCC提供的CO2排放量计算方法仅考虑一次能源燃料所产生的CO2,来考虑到二次能源省际调配的情况,不能真实反映各省CO

  9. Progress of research and technology in conversion and utilization of carbon dioxide%CO2的绿色利用技术研究进展

    Institute of Scientific and Technical Information of China (English)

    王文珍; 张生琦; 倪炳华; 屈撑囤; 黄风林; 黄俊; 王丽莎

    2013-01-01

      近年来 CO2的综合利用越来越引起人们的重视。本文介绍了近年来通过化学途径实现CO2资源化利用的研究方向及进展,并报道了最新的研究技术和成果。通过适当的化学反应,CO2可以转化为液体燃料、甲醇、碳酸酯类等高附加值的产品,还可通过 CH4–CO2催化重整制成合成气来制备乙烯或含氧化合物等。另外,本文还介绍了其它新型 CO2化学利用技术,如通过合理设计的化学肺可将 CO2直接转换为氧气,利用太阳能、电能和生物微藻技术实现CO2向有用化学品的转化以及作为新型储氢材料的研究利用进展。%This paper reviewed and analyzed the progress on research and technology of conversion and utilization of CO2 by chemical route in recent years. CO2 can be converted into liquid fuel, methanol,carbonates,and other high value products through proper chemical reactions. CO2 can also be converted to olefin or oxygen-containing compounds through the process of CO2 – Methane synthesis. Other new technologies of CO2 utilization,including direct conversion of CO2 into oxygen through rational designed chemical lungs,conversion of CO2 into useful chemicals by solar energy, electricity and biological microalgae technologies,and progress of CO2 utilization as new hydrogen storage materials.

  10. Attracting effects of carbon dioxide lamps versus ultraviolet light on mosquitoes%CO2灯诱法与紫外灯诱法捕蚊效果比较

    Institute of Scientific and Technical Information of China (English)

    任彤; 刘艳华; 王艺凯; 田洁; 张丽杰; 郭惠琳; 郭天宇

    2011-01-01

    Objective To compare the attracting effects of carbon dioxide (CO2) traps with ultraviolet (UV) light traps on mosquitoes in field settings. Methods Both approaches were used within a 2-hour window before and after sunset, three times monthly, for six consecutive months. Results A total of 2483 mosquitoes were captured, of which 1544 were attracted by CO2 traps and 939 by UV light. The density of mosquitoes captured by CO2 traps (11.20/lamp· hour) was significantly higher than by UV light traps (6.87/light· hour). Conclusion The attracting effect of carbon dioxide traps was better than that of UV light traps.CO2 traps can be used to effectively monitor mosquito density.%目的 现场调查CO2灯诱法与紫外灯诱法的捕蚊效果.方法 以每月3次的频率分别于日落前后2h,同时采取CO2灯诱法和紫外灯诱法诱捕蚊虫,连续诱捕6个月.结果 2种方法共捕获成蚊2483只,其中CO2灯诱法捕获成蚊1544只,紫外灯诱法捕获成蚊939只;CO2灯诱法捕获的成蚊密度[11.20只/(灯·h)]显著高于紫外灯诱法[6.87只/(灯·h).结论 CO2灯诱法捕蚊效果好于紫外灯诱法,是蚊虫密度监测的一种有效方法.

  11. 生物质炭施用量及水热条件对淹水土壤 CO2释放的影响%Effects of carbon dioxide emissions from waterlogged soils by biochar amendments and hydrothermal condition

    Institute of Scientific and Technical Information of China (English)

    花莉; 唐志刚; 洛晶晶; 贾卫华

    2013-01-01

    通过模拟土柱实验,向水稻土中添加质量分数分别为0%(C0)、2%(C2)、5%(C5)、8%(C8)的生物质炭,并在不同淹水深度和温度下培养,旨在了解生物质炭的施用量及其水热条件对土壤CO2释放的影响,以期通过控制生物质炭的施炭量和改进农田管理措施,从而为农业温室气体碳减排提供依据.研究结果发现:施加生物质炭对土壤CO2释放的抑制作用明显,与对照相比,2%、5%、8%施炭量处理的土壤CO2累计释放量分别降低了5.1%、2.4%和26.5%.低施炭量对土壤CO2的释放降幅较少,而较高施炭量可能对抑制土壤CO2释放的效果更好;温度越高,土壤的呼吸作用越强,CO2释放速率也越快;在昼夜变化上,土壤夜间CO2的释放速率要高于白天;就淹水深度而言,土壤灌水深度愈深,CO2的释放速率愈低.此外,还从施炭量和水热条件对土壤CO2和CH4释放的综合排放效应进行了展望.%A waterlogged soil environment was simulated and added with mass fraction of 0%(C0) ,2% (C2) ,5% (C5) ,and 8% (C8) of biochar to paddy soils to realize the effects of carbon dioxide emissions by biochar amendments and hydrothermal condition under different irrigated water depths and culture temperature .It is aimed at decreasing agricultural green-house gases emissions by means of controlling biochar amendments and improving field man-agement measures .The results showed that there is a significant inhibition of carbon dioxide emission from soils due to biochar amendment .Compared with the control ,cumulative car-bon dioxide emissions from soils by biochar addition of 2% ,5% ,and 8% were reduced by 5 .1% ,2 .4% and 26 .5% respectively .In terms of inhibition of carbon dioxide emission from soils by biochar amendment ,higher biochar amendments might be better than lower amend-ments;with the higher temperature ,the stronger soil respiration became

  12. Synthesis of nesquehonite by reaction of gaseous CO2 with Mg chloride solution: its potential role in the sequestration of carbon dioxide.

    Science.gov (United States)

    Ferrini, Vincenzo; De Vito, Caterina; Mignardi, Silvano

    2009-09-15

    In this paper is reported a novel method to synthesize nesquehonite, MgCO(3) x 3H(2)O, via reaction of a flux of CO(2) with Mg chloride solution at 20+/-2 degrees C. The reaction rate is rapid, with carbonate deposition almost complete in about 10 min. The full characterization of the product of synthesis has been performed to investigate its potential role as a "CO(2)-sequestering medium" and a means of disposing Mg-rich wastewater. We investigated the nesquehonite synthesized using SEM, XRD, FTIR and thermal analysis. The thermodynamic and chemical stability of this low-temperature hydrated carbonate of Mg and its possible transformation products make our method a promising complementary solution to other methods of CO(2) sequestration. Carbonation via magnesium chloride aqueous solutions at standard conditions represents a simple and permanent method of trapping CO(2). It could be applied at point sources of CO(2) emission and could involve rejected brine from desalination plants and other saline aqueous wastes (i.e., "produced water"). The likelihood of using the resulting nesquehonite and the by-products of the process in a large number of applications makes our method an even more attractive solution. PMID:19303209

  13. Impact of CO2 leakage from sub-seabed carbon dioxide capture and storage (CCS) reservoirs on benthic virus–prokaryote interactions and functions

    Science.gov (United States)

    Rastelli, Eugenio; Corinaldesi, Cinzia; Dell’Anno, Antonio; Amaro, Teresa; Queirós, Ana M.; Widdicombe, Stephen; Danovaro, Roberto

    2015-01-01

    Atmospheric CO2 emissions are a global concern due to their predicted impact on biodiversity, ecosystems functioning, and human life. Among the proposed mitigation strategies, CO2 capture and storage, primarily the injection of CO2 into marine deep geological formations has been suggested as a technically practical option for reducing emissions. However, concerns have been raised that possible leakage from such storage sites, and the associated elevated levels of pCO2 could locally impact the biodiversity and biogeochemical processes in the sediments above these reservoirs. Whilst a number of impact assessment studies have been conducted, no information is available on the specific responses of viruses and virus–host interactions. In the present study, we tested the impact of a simulated CO2 leakage on the benthic microbial assemblages, with specific focus on microbial activity and virus-induced prokaryotic mortality (VIPM). We found that exposure to levels of CO2 in the overlying seawater from 1,000 to 20,000 ppm for a period up to 140 days, resulted in a marked decrease in heterotrophic carbon production and organic matter degradation rates in the sediments, associated with lower rates of VIPM, and a progressive accumulation of sedimentary organic matter with increasing CO2 concentrations. These results suggest that the increase in seawater pCO2 levels that may result from CO2 leakage, can severely reduce the rates of microbial-mediated recycling of the sedimentary organic matter and viral infections, with major consequences on C cycling and nutrient regeneration, and hence on the functioning of benthic ecosystems. PMID:26441872

  14. The Greenhouse effect: impacts of ultraviolet-B (UV-B) radiation, carbon dioxide (CO2), and ozone (O3) on vegetation.

    Science.gov (United States)

    Krupa, S V; Kickert, R N

    1989-01-01

    There is a fast growing and an extremely serious international scientific, public and political concern regarding man's influence on the global climate. The decrease in stratospheric ozone (O3) and the consequent possible increase in ultraviolet-B (UV-B) is a critical issue. In addition, tropospheric concentrations of 'greenhouse gases' such as carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4) are increasing. These phenomena, coupled with man's use of chlorofluorocarbons (CFCs), chlorocarbons (CCs), and organo-bromines (OBs) are considered to result in the modification of the earth's O3 column and altered interactions between the stratosphere and the troposphere. A result of such interactions could be the global warming. As opposed to these processes, tropospheric O3 concentrations appear to be increasing in some parts of the world (e.g. North America). Such tropospheric increases in O3 and particulate matter may offset any predicted increases in UV-B at those locations. Presently most general circulation models (GCMs) used to predict climate change are one- or two-dimensional models. Application of satisfactory three-dimensional models is limited by the available computer power. Recent studies on radiative cloud forcing show that clouds may have an excess cooling effect to compensate for a doubling of global CO2 concentrations. There is a great deal of geographic patchiness or variability in climate. Use of global level average values fails to account for this variability. For example, in North America: 1. there may be a decrease in the stratospheric O3 column (1-3%); however, there appears to be an increase in tropospheric O3 concentrations (1-2%/year) to compensate up to 20-30% loss in the total O3 column; 2. there appears to be an increase in tropospheric CO2, N2O and CH4 at the rate of roughly 0.8%, 0.3% and 1-2%, respectively, per year; 3. there is a decrease in erythemal UV-B; and 4. there is a cooling of tropospheric air temperature due to

  15. CAPTURING EXHAUST CO2 GAS USING MOLTEN CARBONATE FUEL CELLS

    Directory of Open Access Journals (Sweden)

    Prateek Dhawan

    2016-03-01

    Full Text Available Carbon dioxide is considered as one of the major contenders when the question of greenhouse effect arises. So for any industry or power plant it is of utmost importance to follow certain increasingly stringent environment protection rules and laws. So it is significant to keep eye on any possible methods to reduce carbon dioxide emissions in an efficient way. This paper reviews the available literature so as to try to provide an insight of the possibility of using Molten Carbonate Fuel Cells (MCFCs as the carbon capturing and segregating devices and the various factors that affect the performance of MCFCs during the process of CO2 capture.

  16. 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...

  17. Carbon dioxide and climate

    International Nuclear Information System (INIS)

    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 CO2 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 CO2 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

  18. On organic soil carbon and CO2

    OpenAIRE

    Bohn, Hinrich L.

    2011-01-01

    Cultivation of virgin lands released about 150 times 1012 kg of carbon as CO2 to the atmosphere during the last 100 years, at rates of 1 to 2 times 1012 kg/yr. These rates exceeded the CO2 evolved from fossil fuel combustion until the mid-1960s. Soil organic carbon, in organic and mineral soils, may play a considerable role in the CO2 cycle and in controlling the CO2 concentration of the atmosphere.DOI: 10.1111/j.2153-3490.1978.tb00863.x

  19. Genomic insights into growth and survival of supercritical-CO2 tolerant bacterium MIT0214 under conditions associated with geologic carbon dioxide sequestration

    Science.gov (United States)

    Peet, K. C.; Freedman, A. J.; Hernandez, H.; Thompson, J. R.

    2011-12-01

    Carbon capture and storage (CCS) of CO2 has the potential to significantly reduce the emissions of greenhouse gasses associated with fossil fuel combustion. The largest potential for storing captured CO2 in the United Sates is in deep geologic saline formations. Currently, little is known about the effects of CO2 storage on biologically active microbial communities found in the deep earth biosphere. Therefore, to investigate how deep earth microbial communities will be affected by the storage of CO2 we have enriched for a microbial consortium from the saline formation waters of the Frio 2 project site (Texas Gulf Coast) that is capable of growth in nutrient media under a supercritical CO2 headspace (Hernandez, et al). The cultivation of actively growing cells in an environment containing scCO2 is unexpected based on previous experimental evidence of microbial sterilization attributed to the acidic, desiccating, and solvent-like properties of scCO2. We have isolated strain MIT0214 from this supercritical CO2 based enrichment and have sequenced its genome using the Illumina platform followed by de novo assembly of reads and targeted Sanger sequencing to reduce gaps in the draft assembly. The genome of strain MIT0214 is approximately 5,551,062 base pairs with 35% GC-content and is most similar to nonpathogenic Bacillus cereus strain ATCC 14597. Annotation of the draft assembly of the MIT0214 genome by the Rapid Annotation using Subsystem Technology (RAST) server revealed 5538 coding sequences where 4145 of the coding sequences were assigned putative functions. These functions were enriched in cell wall and capsule formation, phage/prophage and plasmids, gene regulation and signaling, and nitrogen and sulfur metabolism relative to the genome of the most closely-related surface-isolated B. cereus reference (ATCC 14597) and in total 773,416 bp of the MIT0214 genome content was distinct from the B. cereus reference. Notably, this set of distinct sequences were most

  20. Hot-water spraying is a sensitive test for signs of life before dressing and scalding in pig abattoirs with carbon dioxide (CO2) stunning.

    Science.gov (United States)

    Parotat, S; von Holleben, K; Arnold, S; Troeger, K; Luecker, E

    2016-02-01

    This study investigated the benefits of hot-water spraying (HWS) as a diagnostic test to verify the absence of signs of life (SOL) before scalding in pigs slaughtered with carbon dioxide (CO2) stunning. A total of 37 108 finishing pigs from five German abattoirs (A to E) operating at 55 to 571 pigs per hour were assessed. Suspended pigs were sprayed onto the muzzle, head and front legs (143 to 258 s post sticking for 4 to 10 s, 57°C to 72°C). Any active movements during HWS were rated as positive test outcomes. In comparison, SOL were considered to be absent if a subsequent manual examination was negative and no active movements were observed following HWS. The incidence of pigs with activity during hot-water spraying (PWA) was restricted to two abattoirs (B: 0.25%; D: 0.02%; A, C, E: 0.00%). PWA showed movements of facial muscles (88%), mouth opening (78%), righting reflex (63%), isolated leg movements (35%) and vocalization (4%). The manual examination was positive in 71% of PWA (corneal/dazzle reflex: 67%/53%, nasal septum pinch: 33%), whereas all inactive pigs tested negative (P99.9% in either case. Any positive manual findings as well as any respiratory activity were instantly terminated using a penetrating captive bolt. Active movements triggered by the shot were shown to be an indicator for SOL (Pactivity (controls). Results for different categories of SM in PWA v. controls were as follows: 100% v. 2.6% for mouth opening, 16.0% v. 0.1% for righting reflex and 22.0% v. 0.9% for isolated leg movements (all P<0.001). First mouth opening after sticking was observed later in PWA (28±24 v. 10±7 s), but mouth openings were observed for a longer period of time (141±44 v. 27±25 s) (both P<0.001). PWA with shorter mouth-opening intervals showed higher movement intensities during HWS and more positive manual findings (P<0.05). We conclude that HWS is a promising test for SOL. SM and sustained mouth opening in particular are indicators for compromised animal

  1. A Quantitative Investigation of CO2 Sequestration by Mineral Carbonation

    CERN Document Server

    Mohammad, Muneer

    2015-01-01

    Anthropogenic activities have led to a substantial increase in carbon dioxide (CO2), a greenhouse gas (GHG), contributing to heightened concerns of global warming. In the last decade alone CO2 emissions increased by 2.0 ppm/yr. globally. In the year 2009, United States and China contributed up to 43.4% of global CO2 emissions. CO2 capture and sequestration have been recognized as promising solutions to mitigate CO2 emissions from fossil fuel based power plants. Typical techniques for carbon capture include post-combustion capture, pre-combustion capture and oxy-combustion capture, which are under active research globally. Mineral carbonation has been investigated as a suitable technique for long term storage of CO2. Sequestration is a highly energy intensive process and the additional energy is typically supplied by the power plant itself. This leads to a reduction in net amount of CO2 captured because of extra CO2 emitted. This paper presents a quantitative analysis of the energy consumption during sequestra...

  2. Influence on Physical and Chemical Properties of Soil for the Leakage of Carbon Dioxide during Geological Storage%地质封存CO2泄露对土壤理化性质的影响

    Institute of Scientific and Technical Information of China (English)

    张丙华; 张倩; 耿春香; 景炯炯

    2016-01-01

    以胜利油田正在实施CO2驱的某区块为研究对象,通过室内模拟试验模拟地质封存CO2泄露,考察CO2泄露时间和速率对土壤理化性质的影响,探讨土壤理化性质变化的机理。研究结果表明,地质封存CO2的泄露会对土壤理化性质产生显著影响,随着CO2泄露浓度的增大,土壤pH降低,土壤含水率降低,有机碳含量降低,碳酸氢根离子含量升高,硫酸根离子、电导率、全氮和磷的含量基本不发生变化。%In order to study the influence on physical and chemical properties of soil for the time and rate of CO2 leakage and explore the mechanism of changes of soil physical and chemical properties, a certain area implemented CO2-driven by SLOF ( shengli Oil Field) was studied by means of indoor simulation experiment which simulated the leakage of Carbon dioxide. It was found that it had the greatest impact on the physical and chemical properties of soil. With the increase of concentration of CO2 leakage, the soil pH, moisture and organic carbon were reduced, HCO-3 was increased, the content of SO2-4 , electrical conductivity, total nitrogen and phosphorus were unchanged.

  3. Research Progress of Low Temperature Carbon Dioxide Solid Adsorbent%低温 CO 2固体吸附剂的研究进展

    Institute of Scientific and Technical Information of China (English)

    程意茹; 张磊; 蒲人娟; 桂建舟; 刘道胜; 刘丹

    2015-01-01

    Along with the global climate warming,carbon capture and sequestration(CCS)have become a hot issue,and raise worldwide attentions in recent years.In this paper,adsorption behavior,influence factors,regeneration ability,potential application and existing problems of several common low-temperature solid adsorbents for CO 2 capturing are reviewed. Meanwhile,the theoretical calculation in the relevant fields is introduced.Finally, a perspective view of the potential development of the solid adsorbents is given.%随着全球气候变暖,CO 2的捕获、存储与转换成为近年来国内外关注的热点问题。综述了几种常见低温固体 CO 2吸附剂的吸附行为、影响因素、再生能力、潜在的应用及存在的问题,并对理论计算该领域的相关应用进行介绍,展望了低温固体 CO 2吸附剂的发展趋势。

  4. Nongovernmental valorization of carbon dioxide

    International Nuclear Information System (INIS)

    Carbon dioxide (CO2) is considered the largest contributor to the greenhouse gas effect. Most attempts to manage the flow of CO2 or carbon into our environment involve reducing net emissions or sequestering the gas into long-lived sinks. Using CO2 as a chemical feedstock has a long history, but using it on scales that might impact the net emissions of CO2 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

  5. CO2催化氢化催化剂及其反应机理综述%Review on Catalysts and Its Mechanisms for Catalytic Hydrogenation of Carbon Dioxide

    Institute of Scientific and Technical Information of China (English)

    张自丽; 赵毅

    2013-01-01

    研究二氧化碳资源化利用技术将对电厂CO2减排工作具有重要意义.综述了基于催化氢化思想的CO2转化催化剂及其反应机理,其主要涉及铜、镍、锌等过渡金属和钌、铱、钯等贵金属.现有催化氢化CO2转化技术研究主要集中于研究与开发高活性催化剂,分析与推测反应机理,提高产物产率及选择性,优化反应体系结构与条件等方面.高活性催化剂如双金属合金,过渡金属催化体系将是未来CO2催化氢化领域主要的研究方向之一.各催化剂催化氢化CO2反应机理较为复杂,值得深入研究.随着经济、环保、节能等新型CO2催化氢化技术的开发及研究的深入,电厂CO2减排及资源化工业应用也将成为可能.%Researches about carbon dioxide utilization technologies will have great significances for the emission reduction of carbon dioxide from power plants.Based on the theory about catalytic hydrogenation,the mechanisms of the catalysts such as transition metals,namely copper,nickel and zinc,and noble metals including ruthenium,iridium and palladium for carbon dioxide conversion were reviewed.Current researches about the catalytic hydrogenation of CO2 mainly focus on the studying and development of highly active catalysts,the analysis and conjecture of reaction mechanism,the improvement of productivity and selectivity,and the optimization of reaction system structure and condition,etc..The highly active catalysts,for example thermometal alloy,and the transition metal catalyst system will be one of the primary issues in the field of CO2 hydrogenation in the future.The reaction mechanism which is complicated with diverse catalysts in carbon dioxide conversion,is worth being researched deeply.As the development of new technics with the characteristics of economy,green and energy saving and the deep researches,it may be possible for the emission reduction and resource industry utilization of CO2 from power plants.

  6. Technical support for an enabling policy framework for carbon dioxide capture and geological storage. Task 3. Incentivising CO2 capture and storage in the EU

    International Nuclear Information System (INIS)

    To date CO2 capture and storage (CCS) is not deployed at a commercial scale, and a range of policy instruments could be used to provide adequate incentives for large scale deployment of CCS in the European Union. Five groups of incentives are discussed: (1) the EU Emissions Trading Scheme (weak and strong version); (2) Member-State-based public financial support through investment support, feed-in subsidies or a CO2 price guarantee; (3) an EU-level low-carbon portfolio standard with tradable certificates; (4) an EU-wide CCS obligation for all new fossil-fuel-based power capacity, and (5) public-private partnerships for realizing a CO2 pipeline infrastructure. The nature of the policy, mainly in case the scale of the instrument matters and much public financial is involved, determines whether it will be implemented by the EU or at the Member-State level. Support for CCS projects at the Member-State level, however, will require amendment of the Community Guidelines for State Aid for Environmental Protection

  7. Life-cycle Assessment of Carbon Dioxide Capture for Enhanced Oil Recovery%为强化石油回采捕集CO2的全周期评估

    Institute of Scientific and Technical Information of China (English)

    E.G Hertwich; M.Aaberg; B.Singh; A.H.Strφmman

    2008-01-01

    The development and deployment of Carbon dioxide Capture and Storage (CCS) technology is a cornerstone of the Norwegian government's climate strategy. A number of projects are currently evaluated/planned along the Norwegian West Coast, one at Tjeldbergodden. CO2 from this project will be utilized in part for enhanced oil recovery in the Halten oil field, in the Norwegian Sea. We study a potential design of such a system. A combined cycle power plant with a gross power output of 832 MW is combined with CO2 capture plant based on a post-combustion capture using amines as a solvent. The captured CO2 is used for enhanced oil recovery (EOR). We employ a hybrid life-cycle assessment (LCA) method to assess the environmental impacts of the system. The study focuses on the modifications and operations of the platform during EOR. We allocate the impacts connected to the capture of CO2 to electricity production, and the impacts connected to the transport and storage of CO2 to the oil produced. Our study shows a substantial reduction of the greenhouse gas emissions from power production by 80% to 75g·(kW·h)-1. It also indicates a reduction of the emissions associated with oil production per unit oil produced, mostly due to the increased oil production. Reductions are especially significant if the additional power demand due to EOR leads to power supply from the land.

  8. Worldwide Innovations in the Development of Carbon Capture Technologies and the Utilization of CO2

    OpenAIRE

    Markewitz, P.; Kuckshinrichs, W.; Leitner, W.; Linssen, J.; Zapp, P.; Bongartz, R. (Roswitha); Schreiber, A.; Müller, T. (Tessa)

    2012-01-01

    While Carbon Capture and Storage (CCS) technologies are being developed with the focus of capturing and storing CO2 in huge quantities, new methods for the chemical exploitation of carbon dioxide (CCU) are being developed in parallel. The intensified chemical or physical utilization of CO2 is targeted at generating value from a limited part of the CO2 stream and developing better and more efficient chemical processes with reduced CO2 footprint. Here, we compare the status of the three main li...

  9. Microbiological monitoring of carbon dioxide storage in a subsurface saline aquifer in Ketzin/Germany within the scope of CO2SINK

    Science.gov (United States)

    Wandrey, M.; Morozova, D.; Zemke, K.; Lerm, S.; Scherf, A.-K.; Vieth, A.; Würdemann, H.; Co2SINK Group

    2009-04-01

    Within the scope of the EU project CO2SINK (www.co2sink.org) a research facility in Ketzin (Germany, west of Berlin) is operated to store CO2 in a saline subsurface aquifer (Würdemann et al., EGU General Assembly 2009). In order to examine the influence of CO2 storage on the environment a comprehensive monitoring program is applied at this site including molecular and microbiological investigations. With the injection of CO2 into the geological formation chemical and physical reservoir characteristics are changed. This may influence the composition and activities of the deep biosphere at the storage horizon. Mineral precipitation, dissolution and corrosion of reservoir casing may be consequences, influencing permeability and long-term stability of the reservoir. The objective of the microbial monitoring program is the characterisation of the microbial community (biocenosis) in fluid samples, as well as in samples from reservoir and cap rock before and during CO2storage using molecular biological methods. 16S rRNA taxonomic studies, Fluorescence in situ hybridisation (FISH), and RealTime PCR are used to examine the composition of the biocenosis. First results of fluid sampling revealed that the microbial community of the saline aquifer is dominated by haloalkaliphilic fermentative bacteria and extremophilic organisms, coinciding with reduced conditions, high salinity and pressure. RealTime RT-PCR of selected genes and the creation and analysis of cDNA libraries will allow the prediction of microbial metabolic activities. In addition, the analysis of organic and inorganic components of the samples will add to the knowledge of possible metabolic shifts during CO2 storage. In order to simulate the storage conditions in situ, long term laboratory experiments in high pressure incubators have been set up using original rock cores from Ketzin. Since DNA and RNA analysis techniques are very sensitive, contamination entries from the adjacent environment have to be excluded

  10. Sequestration of CO2 by concrete carbonation.

    Science.gov (United States)

    Galan, Isabel; Andrade, Carmen; Mora, Pedro; Sanjuan, Miguel A

    2010-04-15

    Carbonation of reinforced concrete is one of the causes of corrosion, but it is also a way to sequester CO2. The characteristics of the concrete cover should ensure alkaline protection for the steel bars but should also be able to combine CO2 to a certain depth. This work attempts to advance the knowledge of the carbon footprint of cement. As it is one of the most commonly used materials worldwide, it is very important to assess its impact on the environment. In order to quantify the capacity of cement based materials to combine CO2 by means of the reaction with hydrated phases to produce calcium carbonate, Thermogravimetry and the phenolphthalein indicator have been used to characterize several cement pastes and concretes exposed to different environments. The combined effect of the main variables involved in this process is discussed. The moisture content of the concrete seems to be the most influential parameter. PMID:20225850

  11. A Carbon Nanotube-based Sensor for CO2 Monitoring

    Directory of Open Access Journals (Sweden)

    Craig A. Grimes

    2001-11-01

    Full Text Available A carbon dioxide (CO2 sensor is fabricated by depositing a thin layer of a multiwall carbon nanotube (MWNT – silicon dioxide (SiO2 composite upon a planar inductorcapacitor resonant circuit. By tracking the resonant frequency of the sensor the complex permittivity of the coating material can be determined. It is shown that the permittivity of MWNTs changes linearly in response to CO2 concentration, enabling monitoring of ambient CO2 levels. The passive sensor is remotely monitored with a loop antenna, enabling measurements from within opaque, sealed containers. Experimental results show the response of the sensor is linear, reversible with no hysteresis between increasing and decreasing CO2 concentrations, and with a response time of approximately 45 s. An array of three such sensors, comprised of an uncoated, SiO2 coated, and a MWNT-SiO2 coated sensors is used to self-calibrate the measurement for operation in a variable humidity and temperature environment. Using the sensor array CO2 levels can be measured in a variable humidity and temperature environment to a ± 3% accuracy.

  12. Progress in Research on Photocatalysts for Photocatalytic Reduction of Carbon Dioxide%光催化还原CO2反应催化剂的研究进展

    Institute of Scientific and Technical Information of China (English)

    李贤达; 单雯妍; 白雪峰

    2011-01-01

    Greenhouse gas CO2 is one of the primary causes of global wanning. Using solar energy to make the reduction of CO2 into hydrocarbon organics will benefit the environmental protection and the efficient utilization of energy. The photocatalysts for the pholocatalytic reduction of carbon dioxide are introduced, including TiO2, metal complexes and some other metal oxides. The process of preparing these catalysts, the feature of structure, the reaction conditions of photocatalytic reduction of CO2 and the existed problems are described. Through the design of catalysts to improve the pho tocatalytic reactivity and the efficient utilization of light will be the focus of future research.%温室气体CO2是全球变暖的一个主要原因,利用太阳能将CO2还原为烃类等有机物将给环境保护和能源利用带来益处.介绍了CO2光催化还原反应中的催化剂,主要涉及TiO2、金属配合物以及一些其它金属氧化物.阐述了各类催化剂的制备过程、结构特征、光催化还原CO2反应条件以及催化剂存在的问题.通过催化剂设计,提高光催化反应活性和光利用效率是今后研究的重点.

  13. Theoretical Insights into the Nature of Nickel-Carbon Dioxide Interactions in Ni(PH3)2(eta2-CO2)

    Czech Academy of Sciences Publication Activity Database

    Kegl, T.; Ponec, Robert; Kollar, L.

    2011-01-01

    Roč. 115, č. 45 (2011), s. 12463-12473. ISSN 1089-5639 R&D Projects: GA ČR GA203/09/0118 Grant ostatní: HSRF(HU) OTKA NK 71906; HSRF(HU) OTKA-NKTH CK 78553; RTI(HU) SROP-4.2.2/08/1/2008-2011 Institutional research plan: CEZ:AV0Z40720504 Keywords : carbon dioxide coordination to Ni * analysis of bonding interactions * density functional methods Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.946, year: 2011

  14. ASSESSMENT OF CARBON DIOXIDE SEQUESTRATION POTENTIAL OF ULTRAMAFIC ROCKS IN CHINA%中国超基性岩封存CO2的潜力研究

    Institute of Scientific and Technical Information of China (English)

    盛雪芬; 季峻峰; 陈骏

    2011-01-01

    大气CO浓度上升引起的气候效应正受到国际社会的高度关注.超基性岩石与CO反应可生成稳定的碳酸盐矿物而永久性地固定CO,有效地降低人类活动排放到大气中CO浓度,从而缓解日趋严重的温室效应带来的全球气候恶化.根据各省记载的超基性岩体的岩石学、地球化学资料,按照公式:T=1/3·a·t·r·d·(1-φ)计算,对各省市自治区的CO封存量进行了详细统计和评估.计算表明,中国超基性岩封存CO的潜力巨大,总封存量可达13.02×10CO,约为2008年全国CO总排放量的1887倍.其中超过11.55×10t CO的封存量(占全国总量的89%)在西藏和新疆地区,其他地区占全国的11%,总量达到1.46x10tCO,相当于2008年全国总排放量的212倍,因此具有较高的碳封存潜力.由于各省工业产业结构分布的不均匀导致CO排放量有着很大的差异,因此利用超基性岩封存CO的潜力相差悬殊.东南沿海和华南地区等经济发达地区相对封存储量较少,应考虑其他方式来封存.%The global is facing a major challenge due to anthropogenic CO2 emission from the utilization of fossil fuels.Ultra-mafic rock storage is potential to reduce the atmospheric CO2 ,with high reactivity to form carbonates leading to a very stable sequestration, eventually to relief the increasingly dangerous global warming originating from the greenhouse effect.After the statistics on the data of petrology and geochemistry of the ultra-mafic rocks recorded in the regional geology of 27 provinces in China,we used the equation: T= 1/3 · a · t · r · d · (1-φ)( T is the potential CO2 storage capacity sequestrating in the ultra-mafic rocks; a is the area of the ultra-mafic rock outcrops; t is the estimated depth of the ultra-mafic rocks; r is how much CO2 can be consumed by 1 t peridotite or 1 t serpentine,which is 0. 63 t and 0. 46 t respectively; d is the densities of the ultra-mafic rocks, peridotite is 3.4g/mi3 and serpentine is

  15. A review of mineral carbonation technologies to sequester CO2.

    Science.gov (United States)

    Sanna, A; Uibu, M; Caramanna, G; Kuusik, R; Maroto-Valer, M M

    2014-12-01

    Carbon dioxide (CO2) capture and sequestration includes a portfolio of technologies that can potentially sequester billions of tonnes of CO2 per year. Mineral carbonation (MC) is emerging as a potential CCS technology solution to sequester CO2 from smaller/medium emitters, where geological sequestration is not a viable option. In MC processes, CO2 is chemically reacted with calcium- and/or magnesium-containing materials to form stable carbonates. This work investigates the current advancement in the proposed MC technologies and the role they can play in decreasing the overall cost of this CO2 sequestration route. In situ mineral carbonation is a very promising option in terms of resources available and enhanced security, but the technology is still in its infancy and transport and storage costs are still higher than geological storage in sedimentary basins ($17 instead of $8 per tCO2). Ex situ mineral carbonation has been demonstrated on pilot and demonstration scales. However, its application is currently limited by its high costs, which range from $50 to $300 per tCO2 sequestered. Energy use, the reaction rate and material handling are the key factors hindering the success of this technology. The value of the products seems central to render MC economically viable in the same way as conventional CCS seems profitable only when combined with EOR. Large scale projects such as the Skyonic process can help in reducing the knowledge gaps on MC fundamentals and provide accurate costing and data on processes integration and comparison. The literature to date indicates that in the coming decades MC can play an important role in decarbonising the power and industrial sector. PMID:24983767

  16. Impact of CO2 leakage from sub-seabed carbon dioxide capture and storage (CCS) reservoirs on benthic virus-prokaryote interactions and functions

    OpenAIRE

    Eugenio eRastelli; Cinzia eCorinaldesi; Antonio eDell'Anno; Teresa eAmaro; Ana M Queiros; Stephen eWiddicombe; Roberto eDanovaro

    2015-01-01

    Atmospheric CO2 emissions are a global concern due to their predicted impact on biodiversity, ecosystems functioning and human life. Among the proposed mitigation strategies, CO2 capture and storage (CCS), primarily the injection of CO2 into marine deep geological formations has been suggested as a technically practical option for reducing emissions. However, concerns have been raised that possible leakage from such storage sites, and the associated elevated levels of pCO2 could locally impac...

  17. Impact of CO2 leakage from sub-seabed carbon dioxide capture and storage (CCS) reservoirs on benthic virus–prokaryote interactions and functions

    OpenAIRE

    Rastelli, Eugenio; Corinaldesi, Cinzia; Dell’Anno, Antonio; Amaro, Teresa; Queirós, Ana M.; Widdicombe, Stephen; Danovaro, Roberto

    2015-01-01

    Atmospheric CO2 emissions are a global concern due to their predicted impact on biodiversity, ecosystems functioning, and human life. Among the proposed mitigation strategies, CO2 capture and storage, primarily the injection of CO2 into marine deep geological formations has been suggested as a technically practical option for reducing emissions. However, concerns have been raised that possible leakage from such storage sites, and the associated elevated levels of pCO2 could locally impact the...

  18. Petrophysical analysis to investigate the effects of carbon dioxide storage in a subsurface saline aquifer at Ketzin, Germany (CO2SINK)

    OpenAIRE

    Kornelia Zemke; Axel Liebscher; Wandrey, M;  

    2010-01-01

    To test the injection behaviour of CO2 into brine-saturated rock and to evaluate the dependence of geophysical properties on CO2 injection, flow and exposure experiments with brine and CO2 were performed on sandstone samples of the Stuttgart Formation representing potential reservoir rocks for CO2 storage. The sandstone samples studied are generally fine-grained with porosities between 17 and 32% and permeabilities between 1 and 100 mD. Additional batch experiments were performed to predict t...

  19. Noble gas and carbon isotopic evidence for CO2-driven silicate dissolution in a recent natural CO2 field

    Science.gov (United States)

    Dubacq, Benoît; Bickle, Mike J.; Wigley, Max; Kampman, Niko; Ballentine, Chris J.; Sherwood Lollar, Barbara

    2012-08-01

    Secure storage of anthropogenic carbon dioxide (CO2) in geological reservoirs requires predicting gas-water-rock interactions over millennial timescales. Noble gases and carbon isotope measurements can be used to shed light on the nature of competing dissolution-precipitation processes over different timescales, from the fast dissolution of gaseous CO2 in groundwater to more sluggish reactions involving dissolution and precipitation of newly formed minerals in the reservoir. Here we study a compilation of gas analyses including noble gases and δ13C of CO2 from nine different natural CO2 reservoirs. Amongst these reservoirs, the Bravo Dome CO2 field (New Mexico, USA) shows distinct geochemical trends which are explained by degassing of noble gases from groundwater altering the composition of the gas phase. This groundwater degassing is synchronous with the dissolution of CO2 in groundwater. Progressive creation of alkalinity via CO2-promoted mineral dissolution is required to explain the observed positive correlation between CO2/3He and δ13C of the gas phase, a unique feature of Bravo Dome. The differences between Bravo Dome and other natural CO2 reservoirs are likely explained by the more recent filling of Bravo Dome, reflecting CO2-water-rock interactions over thousands of years rather than over millions of years in older reservoirs.

  20. 短波红外通道CO2观测的温度敏感性分析%Temperature sensitivity analysis of carbon dioxide measurement in SWIR band

    Institute of Scientific and Technical Information of China (English)

    邹铭敏; 陈良富; 陶金花; 苏林; 韩冬; 贺宝华; 张莹; 余超

    2012-01-01

    Carbon dioxide has an absorption band of solar spectra in SWIR, and temperature is a key factor to the absorption effect. Researches on the CO2 observation sensitivity of temperature are done in this paper. First, the dependences of spectral line parameters on temperature are discussed. Then, according to the accuracy level of atmosphere temperature profile product, we simulate the change of measurement in nadir mode by importing 1 K temperature uncertainty , using line-by-line radiative transfer mode under 6 different atmosphere modes, and calculate the corresponding change of retrieval result. In contrast, simulations of measurement change resulted from 1 ppm and 2 ppm CO2 column density differences are also done. After comparison, we come to a conclusion; 1 K uncertainty of atmosphere temperature profile is an important factor which has significant influence to high precise atmospheric CO2 observation.%近红外通道观测大气CO2含量是利用其对太阳辐射的吸收作用,温度是影响吸收气体吸收的一个重要因子,文中讨论了CO2观测的温度敏感性.首先阐述了温度对气体吸收谱线的强度、增宽的影响;然后根据CO2反演过程中使用的大气温度产品的精度水平,利用逐线积分辐射传输模型模拟计算了1K的随机温度误差对垂直大气观测的影响,以及由此导致的CO2反演误差,并与模拟的1 ppm和2 ppm的CO2浓度变化所造成的观测与反演变化量进行了比较.通过对比分析六种大气模式下的模拟计算结果,得出1K大气随机温度误差是影响高精度大气CO2观测反演的重要因子.

  1. Fluxes of N2O, CH4 and CO2 in a meadow ecosystem exposed to elevated ozone and carbon dioxide for three years

    International Nuclear Information System (INIS)

    Open-top chambers (OTCs) were used to evaluate the effects of moderately elevated O3 (40-50 ppb) and CO2 (+100 ppm) and their combination on N2O, CH4 and CO2 fluxes from ground-planted meadow mesocosms. Bimonthly measurements in 2002-2004 showed that the daily fluxes of N2O, CH4 and CO2 reacted mainly to elevated O3, while the fluxes of CO2 also responded to elevated CO2. However, the fluxes did not show any marked response when elevated O3 and CO2 were combined. N2O and CO2 emissions were best explained by soil water content and air and soil temperatures, and they were not clearly associated with potential nitrification and dentrification. Our results suggest that the increasing O3 and/or CO2 concentrations may affect the N2O, CH4 and CO2 fluxes from the soil, but longer study periods are needed to verify the actual consequences of climate change for greenhouse gas emissions. - The soil fluxes of N2O, CH4 and CO2 in a meadow ecosystem changed in response to elevated O3 and CO2 in an OTC experiment

  2. Carbon dioxide vs. air insufflation in ileo-colonoscopy and in gastroscopy plus ileo-colonoscopy: a comparative study Insuflación de CO2 vs. aire en íleo-colonoscopia y en gastroscopia más íleo-colonoscopia: estudio comparativo

    OpenAIRE

    María Fernández-Calderón; Miguel Ángel Muñoz-Navas; Juan Carrascosa-Gil; María Teresa Betés-Ibañez; Susana de-la Riva; César Prieto-de-Frías; María Teresa Herráiz-Bayod; Cristina Carretero-Ribón

    2012-01-01

    Introduction: insufflation with carbon dioxide (CO2) during endoscopies compared to air is associated with a decrease in abdominal discomfort after the examination, because CO2 is readily absorbed through the small intestine and eliminated by the lungs. Aims: the objective of this randomized clinical trial was to assess the effect of CO2 insufflation on pain and abdominal distension after an ileo-colonoscopy (I) and after an ileo-colonoscopy plus gastroscopy (I+G). Material and methods: we in...

  3. Experimental and Modeling Studies on the Solubility of Sub- and Supercritical Carbon Dioxide (scCO2) in Potato Starch and Derivatives

    OpenAIRE

    Muljana, Henky; Picchioni, Francesco; Heeres, Hero J.; Janssen, Leon P.B.M.; 068883455

    2011-01-01

    The solubility of CO2 in native potato starch (NPS) and potato starch acetate (SA) at two different temperatures (50°C and 120°C) and various pressures (up to 25 MPa) was determined using a magnetic suspension balance. Within the experimental window, a maximum solubility of 31 mg CO2/gsample for NPS and 79.4 mg CO2/gsample for SA was obtained. The CO2 sorption behavior is highly depending on the temperature and pressure. The solubility data were modeled with the Sanchez Lacombe equation of st...

  4. The utilisation of fly ash in CO2 mineral carbonation

    Directory of Open Access Journals (Sweden)

    Jaschik Jolanta

    2016-03-01

    Full Text Available The fixation of CO2 in the form of inorganic carbonates, also known as mineral carbonation, is an interesting option for the removal of carbon dioxide from various gas streams. The captured CO2 is reacted with metal-oxide bearing materials, usually naturally occurring minerals. The alkaline industrial waste, such as fly ash can also be considered as a source of calcium or magnesium. In the present study the solubility of fly ash from conventional pulverised hard coal fired boilers, with and without desulphurisation products, and fly ash from lignite fluidised bed combustion, generated by Polish power stations was analysed. The principal objective was to assess the potential of fly ash used as a reactant in the process of mineral carbonation. Experiments were done in a 1 dm3 reactor equipped with a heating jacket and a stirrer. The rate of dissolution in water and in acid solutions was measured at various temperatures (20 - 80ºC, waste-to-solvent ratios (1:100 - 1:4 and stirrer speeds (300 - 1100 min-1. Results clearly show that fluidised lignite fly ash has the highest potential for carbonation due to its high content of free CaO and fast kinetics of dissolution, and can be employed in mineral carbonation of CO2.

  5. Carbon dioxide emission reduction measures and cost analysis in thermal power plant%火电厂CO2减排技术及成本探讨

    Institute of Scientific and Technical Information of China (English)

    丁炜; 朱林

    2011-01-01

    介绍了我国火电厂CO2排放特点,阐述了火电厂CO2 减排技术、成本及影响因素,分析了CO2 减排对中国未来能源和经济的影响.指出最适合CO2 捕集技术发展的电厂类型是超超临界燃煤电厂和IGCC电厂,CO2减排技术的研发重点是大幅度降低成本和效率损失.

  6. Phenol-Formaldehyde Resin-Based Carbons for CO2 Separation at Sub-Atmospheric Pressures

    OpenAIRE

    Noelia Álvarez-Gutiérrez; María Victoria Gil; María Martínez; Fernando Rubiera; Covadonga Pevida

    2016-01-01

    The challenge of developing effective separation and purification technologies that leave much smaller energy footprints is greater for carbon dioxide (CO2) than for other gases. In addition to its involvement in climate change, CO2 is present as an impurity in biogas and bio-hydrogen (biological production by dark fermentation), in post-combustion processes (flue gas, CO2-N2) and many other gas streams. Selected phenol-formaldehyde resin-based activated carbons prepared in our laboratory hav...

  7. 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....

  8. Spatial and Temporal Variability of Carbon Dioxide using Structure Functions in Urban Areas: Insights for Future Active Remote CO2 Sensors

    Science.gov (United States)

    Choi, Y.; Yang, M. M.; Kooi, S. A.; Browell, E. V.; DiGangi, J. P.

    2015-12-01

    High resolution in-situ CO2 measurements were recorded onboard the NASA P-3B during the DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) Field Campaigns during July 2011 over Washington DC/Baltimore, MD; January - February 2013 over the San Joaquin Valley, CA; September 2013 over Houston, TX; and July-August 2014 over Denver, CO. Each of these campaigns have approximately two hundred vertical soundings of CO2 within the lower troposphere (surface to about 5 km) at 6-8 different sites in each of the urban area. In this study, we used structure function analysis, which are a useful way to quantify spatial and temporal variability, by displaying differences with average observations, to evaluate the variability of CO2 in the 0-2 km range (representative of the planetary boundary layer). These results can then be used to provide guidance in the development of science requirements for the future ASCENDS (Active Sensing of CO2 Emissions over Nights, Days, and Seasons) mission to measure near-surface CO2 variability in different urban areas. We compare the observed in-situ CO2 variability with the variability of the CO2 column-averaged optical depths in the 0-1 km and 0-3.5 km altitude ranges in the four geographically different urban areas, using vertical weighting functions for potential future ASCENDS lidar CO2 sensors operating in the 1.57 and 2.05 μm measurement regions. In addition to determining the natural variability of CO2 near the surface and in the column, radiocarbon and anthropogenic pollution tracers are used to examine the variation of emission sources among these urban sites.

  9. Thermodynamic analysis and optimization of a solar-powered transcritical CO2 (carbon dioxide) power cycle for reverse osmosis desalination based on the recovery of cryogenic energy of LNG (liquefied natural gas)

    International Nuclear Information System (INIS)

    A solar-powered transcritical CO2 (carbon dioxide) power cycle for reverse osmosis desalination based on the recovery of cryogenic energy of LNG (liquefied natural gas) is proposed. The system consists of a solar collector subsystem, a transcritical CO2 power cycle subsystem, a LNG subsystem and a RO (reverse osmosis) desalination subsystem. A thermal storage unit is introduced into the system to guarantee continuous and stable operation of the system. A mathematical model is developed to simulate the system based on several assumptions. The effects of several key thermodynamic parameters on the system performance are examined based on the performance criteria, including daily exergy efficiency, daily mechanical work output and daily fresh work output. Parametric optimization is conducted by genetic algorithm to maximize the daily fresh water output. The results show that the CO2 turbine inlet pressure has an optimal value to reach the daily maximum exergy efficiency under the given conditions. The daily exergy efficiency could decrease with an increase in condenser temperature, and increase with an increase in mass flow rate of oil and NG turbine inlet pressure. Through parametric optimization, the system can reach the daily exergy efficiency of 4.90% and provide 2537.33 m3 fresh water per day under the given conditions. - Highlights: • A solar-powered transcritical CO2 cycle with LNG as heat sink for RO is proposed. • Parametric sensitive analysis is done to examine their effects on the performance. • Parametric optimization is conducted to obtain optimum system performance

  10. 考虑地层水的凝析气井注CO2提高产能研究%Productivity of gas-condensate well containing formation water improved by carbon dioxide injection

    Institute of Scientific and Technical Information of China (English)

    张楠

    2013-01-01

    CO2吞吐被认为是解除凝析气井反凝析污染、提高气井产能的较好方法。利用CMG数值模拟软件,以一口实际的含水凝析气井数据为基础,建立了单井径向数值模拟模型。对比研究凝析气井自然衰竭开采和注CO2吞吐不同情况下,反凝析液饱和度和气相相对渗透率的变化规律,并利用陈元千的“动态污染表皮系数”法进行产能提高效果评价。研究表明:反凝析现象在近井带形成了一个10m左右的动态径向污染区,致使气井产能急剧下降。注CO2吞吐可通过CO2与凝析液的反蒸发作用有效地消除近井带的反凝析液污染,从而提高气井产能。CO2注入量越大,吞吐效果越好,但也存在一个最优值(实例为16×104 m3),超过后的产能提高幅度明显减小,而注入速度和焖井时间对产能的提高不敏感。%The CO2 huff-and-puff technology is considered a better technique to remove retrograde condensate pollu-tion and improve productivity of gas-condensate wells.On the basis of actual data of a gas-condensate well containing for-mation water,a single well radial model was established by adopting the numerical simulation software (CMG).It was studied on change laws of retrograde condensate liquid saturation and gas phase relative permeability under the conditions of nature depletion and CO2 huff-and-puff of the gas-condensate well.And then productivity improvement effect was evaluated by using Chen Yuanqian’s method,namely the dynamic pollution skin factor method.Simulation results indicate that because of the retrograde condensation,a dynamic radial pollution area of about 10 meters was formed near wellbore,which leads to a sharpy decrease of gas well production.The formation damage near wellbore can be effectively removed by the reverse evapo-ration of CO2 and condensate liquid.As a result,the gas well production can be increased.The more the injected volume of carbon dioxide

  11. 基于原子和分子谱线分析的 LIBS 快速测量 CO2%Rapid Measurement of Carbon Dioxide with Laser-Induced Breakdown Spectroscopy Based on Atomic and Molecular Spectrum

    Institute of Scientific and Technical Information of China (English)

    徐嘉隆; 李越胜; 陆继东; 白凯杰; 卢伟业; 姚顺春

    2016-01-01

    作为温室气体的主要成分,CO2的排放控制有利于应对全球气候变暖以及生态环境变化,对 CO2的快速检测具有重要意义。目前检测 CO2的方法有滴定法,电化学法,气相色谱法,红外吸收光谱法等,但对应用于工业现场的在线监测还存在着不足。激光诱导击穿光谱(LIBS)具有远程测量,无需或仅需简单预处理,多组分同步测量等优点,本文提出将其应用于 CO2在线监测,期望发展适用于工业过程碳排放的在线监测技术。利用质量流量控制器控制纯度为99.99%的 CO2和 N2配比形成不同 CO2浓度的混合气体模拟烟气环境,经过混气瓶充分混合后送入密封样品池进行 LIBS 测量实验。研究不同延迟时间下 C247.86 nm 和 CN38.34 nm 谱线的演化规律,验证了等离子体形成过程中存在部分 CO2分子解离反应生成 CN 分子,在 CO2定量分析时应考虑 CN 分子谱线的影响,并获得同步测量 C 原子和分子谱线的最佳延迟时间为800 ns 。在此基础上,由于等离子体演化过程中,各种信息相互影响,分析指标与多个测量参数存在关系,综合考虑 C 原子、CN 碎片及修正高浓度影响下的自吸收效应,采用多元回归分析方法建立了 CO2定量分析曲线,其拟合度 R2和斜率分别达到了0.978和0.981,结果表明相比单个指标直接定标,该方法提高了定量分析模型的可靠性,验证了 LIBS 技术快速测量 CO2的可行性。%With the rapid development of economy and industrialization ,global warming is becoming the most serious sensitive global climate issues ,which causes the rising of sea level and many other negative effects .The cause of global warming is the emission of greenhouse gases and carbon dioxide is the main component of greenhouse gases .The control of CO2 emssion is bene‐ficial to addressing gobal climate change and environmental degradation .Therefore ,it

  12. Forgotten carbon: indirect CO2 in greenhouse gas emission inventories

    International Nuclear Information System (INIS)

    National governments that are Parties to the United Nations Framework Convention on Climate Change (UNFCCC) are required to submit greenhouse gas (GHG) inventories accounting for the emissions and removals occurring within their geographic territories. The Intergovernmental Panel on Climate Change (IPCC) provides inventory methodology guidance to the Parties of the UNFCCC. This methodology guidance, and national inventories based on it, omits carbon dioxide (CO2) from the atmospheric oxidation of methane, carbon monoxide, and non-methane volatile organic compounds emissions that result from several source categories. The inclusion of this category of 'indirect' CO2 in GHG inventories increases global anthropogenic emissions (excluding land use and forestry) between 0.5 and 0.7%. However, the effect of inclusion on aggregate UNFCCC Annex I Party GHG emissions would be to reduce the growth of total emissions, from 1990 to 2004, by 0.2% points. The effect on the GHG emissions and emission trends of individual countries varies. The paper includes a methodology for calculating these emissions and discusses uncertainties. Indirect CO2 is equally relevant for GHG inventories at other scales, such as global, regional, organizational, and facility. Similarly, project-based methodologies, such as those used under the Clean Development Mechanism, may need revising to account for indirect CO2

  13. 商业硅胶负载PEI对CO2的吸附捕集研究%Adsorption of carbon dioxide on polyethylenimine loaded commercial silica gel

    Institute of Scientific and Technical Information of China (English)

    韩淑怡; 王科; 商红岩; 查庆芳; 阎子峰; 周明宇; 冼祥发

    2013-01-01

    A serial of polyethylenimine (PEI) functionalized commercial silica gel modified by urea calcination method were prepared by wet impregnation method,and their adsorption performances of CO2 as well as the effect of urea calcination method on the structure of the silica gel were investigated.The results showed that the pore structure and surface area of the silica gel could be adjusted efficiently by urea calcinations method,and the PEI functionalized silica gel adsorbents exhibited an excellent performance for CO2 adsorption.When the PEI loading amount of the adsorbent was 30% by mass,the adsorbent had the best CO2 uptake capacity,which was up to 93.4 mg per gram adsorbent.In addition,the PEI-impregnated silica gel showed stable adsorptiondesorption behavior during 8 consecutive test cycles.%采用浸渍法制备了商业硅胶负载聚乙烯亚胺(PEI)的CO2吸附剂,研究了该类吸附剂对CO2的吸附捕集性能,同时考察了尿素焙烧法对硅胶孔结构的影响.结果表明:尿素焙烧法可以有效调变商业硅胶的孔结构和比表面积;由硅胶为载体负载PEI后制备的吸附剂具有良好的CO2吸附性能,当PEI负载质量分数为30%时,CO2吸附量最大值可达93.4mg/g;并且在8次吸附-脱附循环测试中CO2吸附量无明显变化,表明该类吸附剂具有良好的CO2吸附再生稳定性能.

  14. Second Generation CO2 FEP Analysis: CASSIF - Carbon Storage Scenario Identification Framework

    NARCIS (Netherlands)

    Yavuz, F.; Tilburg, T. van; David, P.; Spruijt, M.; Wildenborg, T.

    2009-01-01

    Carbon dioxide Capture and Storage (CCS) is a promising contribution to reduce further increase of atmospheric CO2 emissions from fossil fuels. The CCS concept anticipates that large amounts of CO2 are going to be stored in the subsurface for the long term. Since CCS is a rather new technology, unce

  15. 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.

  16. Bi-reforming of methane from any source with steam and carbon dioxide exclusively to metgas (CO-2H2) for methanol and hydrocarbon synthesis.

    Science.gov (United States)

    Olah, George A; Goeppert, Alain; Czaun, Miklos; Prakash, G K Surya

    2013-01-16

    A catalyst based on nickel oxide on magnesium oxide (NiO/MgO) thermally activated under hydrogen is effective for the bi-reforming with steam and CO(2) (combined steam and dry reforming) of methane as well as natural gas in a tubular flow reactor at elevated pressures (5-30 atm) and temperatures (800-950 °C). By adjusting the CO(2)-to-steam ratio in the gas feed, the H(2)/CO ratio in the produced syn-gas could be easily adjusted in a single step to the desired value of 2 for methanol and hydrocarbon synthesis. PMID:23256664

  17. Miniature Carbon Dioxide Sensor for Small Unmanned Aircraft Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — There is a growing need to develop improved technologies for precise airborne measurements of carbon dioxide, CO2. CO2 measurements are of great importance to many...

  18. Simultaneous effect of nitrate (NO3- concentration, carbon dioxide (CO2 supply and nitrogen limitation on biomass, lipids, carbohydrates and proteins accumulation in Nannochloropsis oculata

    Directory of Open Access Journals (Sweden)

    Aarón Millán-Oropeza

    2015-03-01

    Full Text Available Biodiesel from microalgae is a promising technology. Nutrient limitation and the addition of CO2 are two strategies to increase lipid content in microalgae. There are two different types of nitrogen limitation, progressive and abrupt limitation. In this work, the simultaneous effect of initial nitrate concentration, addition of CO2, and nitrogen limitation on biomass, lipid, protein and carbohydrates accumulation were analyzed. An experimental design was established in which initial nitrogen concentration, culture time and CO2 aeration as independent numerical variables with three levels were considered. Nitrogen limitation was taken into account as a categorical independent variable. For the experimental design, all the experiments were performed with progressive nitrogen limitation. The dependent response variables were biomass, lipid production, carbohydrates and proteins. Subsequently, comparison of both types of limitation i.e. progressive and abrupt limitation, was performed. Nitrogen limitation in a progressive mode exerted a greater effect on lipid accumulation. Culture time, nitrogen limitation and the interaction of initial nitrate concentration with nitrogen limitation had higher influences on lipids and biomass production. The highest lipid production and productivity were at 582 mgL-1 (49.7 % lipid, dry weight basis and 41.5 mgL-1d-1, respectively; under the following conditions: 250 mgL-1 of initial nitrate concentration, CO2 supply of 4% (v/v, 12 d of culturing and 2 d in state of nitrogen starvation induced by progressive limitation. This work presents a novel way to perform simultaneous analysis of the effect of the initial concentration of nitrate, nitrogen limitation, and CO2 supply on growth and lipid production of Nannochloropsis oculata, with the aim to produce potential biofuels feedstock.

  19. Leakage and Seepage of CO2 from Geologic Carbon Sequestration Sites: CO2 Migration into Surface Water

    International Nuclear Information System (INIS)

    Geologic carbon sequestration is the capture of anthropogenic carbon dioxide (CO2) and its storage in deep geologic formations. One of the concerns of geologic carbon sequestration is that injected CO2 may leak out of the intended storage formation, migrate to the near-surface environment, and seep out of the ground or into surface water. In this research, we investigate the process of CO2 leakage and seepage into saturated sediments and overlying surface water bodies such as rivers, lakes, wetlands, and continental shelf marine environments. Natural CO2 and CH4 fluxes are well studied and provide insight into the expected transport mechanisms and fate of seepage fluxes of similar magnitude. Also, natural CO2 and CH4 fluxes are pervasive in surface water environments at levels that may mask low-level carbon sequestration leakage and seepage. Extreme examples are the well known volcanic lakes in Cameroon where lake water supersaturated with respect to CO2 overturned and degassed with lethal effects. Standard bubble formation and hydrostatics are applicable to CO2 bubbles in surface water. Bubble-rise velocity in surface water is a function of bubble size and reaches a maximum of approximately 30 cm s-1 at a bubble radius of 0.7 mm. Bubble rise in saturated porous media below surface water is affected by surface tension and buoyancy forces, along with the solid matrix pore structure. For medium and fine grain sizes, surface tension forces dominate and gas transport tends to occur as channel flow rather than bubble flow. For coarse porous media such as gravels and coarse sand, buoyancy dominates and the maximum bubble rise velocity is predicted to be approximately 18 cm s-1. Liquid CO2 bubbles rise slower in water than gaseous CO2 bubbles due to the smaller density contrast. A comparison of ebullition (i.e., bubble formation) and resulting bubble flow versus dispersive gas transport for CO2 and CH4 at three different seepage rates reveals that ebullition and bubble

  20. GC-MS Analysis of Supercritical Carbon Dioxide Fluid Extract from Litchi Seeds%GC-MS分析荔枝核超临界CO2萃取物

    Institute of Scientific and Technical Information of China (English)

    饶长全; 乔方; 王燕; 黄略略

    2012-01-01

    Supercritical carbon dioxide fluid (SCDF) extract from litchi seeds was prepared and analyzed by GC-MS for volatile composition. The extraction efficiency of SCDF extract was 4.26%. A total of 67 compounds were identified from the extract, mainly including phytosterols, terpenoids, unsaturated fatty acids, hexadecanoic acid, fatty acid ester and vitamin E with relative contents of 31.3%, 25.7%, 12.03%, 9.63%, 7.53% and 7.21%, respectively.%采用超临界CO2萃取荔枝核,并用气相色谱-质谱联用仪对荔枝核萃取物的挥发性成分进行分析。结果表明:超临界CO2萃取荔枝核的萃取率为4.26%,气相色谱-质谱联用鉴定出67种化合物,主要为甾醇类、萜类、不饱和脂肪酸、棕榈酸、脂肪酸酯、VE,相对含量分别为31.3%、25.7%、12.03%、9.63%、7.53%、7.21%。

  1. Carbon Dioxide in Arable Soil Profiles

    DEFF Research Database (Denmark)

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

    2014-01-01

    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 on the...

  2. Technology for volatile oil extraction from the root of Arctium Lappa L.using supercrit-ical carbon dioxide%牛蒡根挥发油超临界CO2萃取的工艺研究

    Institute of Scientific and Technical Information of China (English)

    窦德宇; 柳春燕; 杨丽芬

    2013-01-01

      Objective:To study the technology for extracting volatile oil from the root of Arctium Lappa L.using supercritical carbon dioxide. Methods:By single factor test,the effects on the yield were examined con-cerning the extraction temperature,pressure and time.Orthogonal experi-ment was used to optimize the extraction technology.Results:The optimal temperature was 45 ℃,pressure at 25 MPa and duration for 1.5 h.Such conditions had led to a yield of volatile oil by 2.92%.Conclusion:Ex-traction of volatile oil from root of Arctium Lappa L.using supercritical carbon dioxide can be productive under the optimum conditions described above.Of the three factors,extraction temperature may greatly affect the extraction yield of volatile oil.%  目的:对超临界CO2流体萃取牛蒡根挥发油的工艺条件进行研究。方法:通过单因素试验研究萃取温度、萃取压力、萃取时间对萃取率的影响,并采用正交试验设计优化工艺条件。结果:最佳萃取条件为萃取温度45℃、萃取压力25 MPa、萃取时间1.5h,在此条件下,超临界CO2流体萃取牛蒡根挥发油的萃取率为2.92%。结论:超临界CO2流体萃取牛蒡根挥发油具有较高的萃取率,最佳条件为萃取温度45℃、萃取压力25 MPa、萃取时间1.5 h,且萃取温度对萃取率有显著影响。

  3. 牛蒡根挥发油超临界CO2萃取的工艺研究%Technology for volatile oil extraction from the root of Arctium Lappa L.using supercrit-ical carbon dioxide

    Institute of Scientific and Technical Information of China (English)

    窦德宇; 柳春燕; 杨丽芬

    2013-01-01

      目的:对超临界CO2流体萃取牛蒡根挥发油的工艺条件进行研究。方法:通过单因素试验研究萃取温度、萃取压力、萃取时间对萃取率的影响,并采用正交试验设计优化工艺条件。结果:最佳萃取条件为萃取温度45℃、萃取压力25 MPa、萃取时间1.5h,在此条件下,超临界CO2流体萃取牛蒡根挥发油的萃取率为2.92%。结论:超临界CO2流体萃取牛蒡根挥发油具有较高的萃取率,最佳条件为萃取温度45℃、萃取压力25 MPa、萃取时间1.5 h,且萃取温度对萃取率有显著影响。%  Objective:To study the technology for extracting volatile oil from the root of Arctium Lappa L.using supercritical carbon dioxide. Methods:By single factor test,the effects on the yield were examined con-cerning the extraction temperature,pressure and time.Orthogonal experi-ment was used to optimize the extraction technology.Results:The optimal temperature was 45 ℃,pressure at 25 MPa and duration for 1.5 h.Such conditions had led to a yield of volatile oil by 2.92%.Conclusion:Ex-traction of volatile oil from root of Arctium Lappa L.using supercritical carbon dioxide can be productive under the optimum conditions described above.Of the three factors,extraction temperature may greatly affect the extraction yield of volatile oil.

  4. Carbon dioxide-guided angioplasty

    International Nuclear Information System (INIS)

    Revascularization procedures are frequently necessary in patients with severe peripheral vascular disease and renal insufficiency (often coexistent with diabetes mellitus). This paper examines the use of carbon dioxide as the contrast agent in percutaneous revascularization procedures (balloon angioplasty). Over the past 10 months, our protocol has used CO2 as the contrast agent for balloon angioplasty in a select group of patients (n = 12) with peripheral vascular disease and renal insufficiency. Some had coexistent diabetes mellitus. With digital subtraction angiography, CO2 was the only contrast agent used during revascularization. Pressure gradients were obtained in appropriate patients

  5. 76 FR 55846 - Hazardous Waste Management System: Identification and Listing of Hazardous Waste: Carbon Dioxide...

    Science.gov (United States)

    2011-09-09

    ... Listing of Hazardous Waste: Carbon Dioxide (CO2) Streams in Geologic Sequestration Activities AGENCY...) to conditionally exclude carbon dioxide (CO 2 ) streams that are hazardous from the definition of... Recovery Act (RCRA) to conditionally exclude carbon dioxide (CO 2 ) streams that are hazardous from...

  6. 高密度CO2处理对E.coli细胞膜渗透性的影响%EFFECT OF DENSE PHASE CARBON DIOXIDE ON MEMBRANE PERMEABILIZATION OF E. coli

    Institute of Scientific and Technical Information of China (English)

    王莹莹; 张德权; 李淑荣; 李娟; 饶伟丽

    2012-01-01

    以E.coli菌悬液为研究对象,通过测定高密度CO2处理(DPCD)后E.coli上清液中蛋白质、核酸、Mg2+、K+离子和丙二醛的含量,辅助透射电镜观察,研究DPCD对E.coli细胞膜渗透性的影响。在7MPa、37℃条件下,E.coli经高密度CO2处理10min后,99%以上的E.coli失活,同时研究发现蛋白质、核酸及Mg2+、K+离子等胞内物质均发生了不同程度的泄漏,丙二醛含量增加,E.coli胞内物质密度降低。密度CO2处理造成E.coli细胞膜渗透性的增加,这也是导致E.coli死亡的原因之一。%To study the effects of dense phase carbon dioxide (DPCD) on membrane permeability of E. coli, the content of protein, nucleic acid, Mg2+ , K+ and malondialdehyde (MDA) of E. coli were studied coupled with Transmission Electron Micrographs (TEM) technique. Under the DPCD condition of 7MPa, 37℃ for 10rain, 99% of E. coli was inactivated. After DPCD treatment, proteins, nucleic acid and Mg2+ , K+ leaked from cells, and the content of MDA increased and the density of substances inside the cell decreased through the TEM view. The results indicated that DPCD treatment caused the membrane permeability of E. coli increased which was also an important cause of cell death.

  7. Methanol absorption characteristics for the removal of H2S (hydrogen sulfide), COS (carbonyl sulfide) and CO2 (carbon dioxide) in a pilot-scale biomass-to-liquid process

    International Nuclear Information System (INIS)

    The BTL (biomass-to-liquid) process is an attractive process that produces liquid biofuels from biomass. The FT (Fisher–Tropsch) process is used to produce synfuels such as diesel and gasoline from gasified biomass. However, the H2S (hydrogen sulfide), COS (carbonyl sulfide) and CO2 (carbon dioxide) in the syngas that are produced from the biomass gasifiers cause a decrease of the conversion efficiency and deactivates the catalyst that is used in the FT process. To remove the acid gases, a pilot-scale methanol absorption tower producing diesel at a rate of 1 BPD (barrel per day) was developed, and the removal characteristics of the acid gases were determined. A total operation time of 500 h was achieved after several campaigns. The average syngas flow rate at the inlet of methanol absorption tower ranged from 300 to 800 L/min. The methanol absorption tower efficiently removed H2S from 30 ppmV to less than 1 ppmV and COS from 2 ppmV to less than 1 ppmV with a removal of CO2 from 20% to 5%. The outlet gas composition adhered to the guidelines for FT reactors. No remaining sulfurous components were found, and the tar component was analyzed in the spent methanol after long-term operations. - Highlights: • The gas cleaning system in a pilot-scale BTL (biomass-to-liquid) process is reported. • Although methanol absorption tower is conventional process, its application to BTL process is attempted. • The methanol absorption tower efficiently removed H2S, COS and CO2 in the syngas. • The sulfurous and tar components in the methanol are analyzed

  8. Leakage and atmospheric dispersion of CO2 associated with carbon capture and storage projects

    OpenAIRE

    Mazzoldi, Alberto

    2009-01-01

    Climate change is affecting planet Earth. The main cause is anthropogenic emissions of greenhouse gases, the principal one being carbon dioxide, released in the atmosphere as a by-product of the combustion of hydrocarbons for the generation of energy. Carbon capture and storage (CCS) is a technology that would prevent carbon dioxide from being emitted into the atmosphere by safely sequestering it underground. For so doing, CO2 must be captured at large emission points and transported at high ...

  9. Nitrogen and Carbon Cycling in a Grassland Community Ecosystem as Affected by Elevated Atmospheric CO2

    OpenAIRE

    Torbert, H.A.; Johnson, H. B.; H. W. Polley

    2012-01-01

    Increasing global atmospheric carbon dioxide (CO2) concentration has led to concerns regarding its potential effects on terrestrial ecosystems and the long-term storage of carbon (C) and nitrogen (N) in soil. This study examined responses to elevated CO2 in a grass ecosystem invaded with a leguminous shrub Acacia farnesiana (L.) Willd (Huisache). Seedlings of Acacia along with grass species were grown for 13 months at CO2 concentrations of 385 (ambient), 690, and 980 μmol mol−1. Elevated CO2 ...

  10. Forsterite Carbonation in Wet Supercritical CO2 and Sodium Citrate

    Science.gov (United States)

    Qiu, L.; Schaef, T.; Wang, Z.; Miller, Q.; McGrail, P.

    2013-12-01

    Lin Qiu1*, Herbert T. Schaef2, Zhengrong Wang1, Quin R.S. Miller3, BP McGrail2 1. Yale University, New Haven, CT, USA 2. Pacific Northwest National Laboratory, Richland, WA, USA 3. University of Wyoming, Laramie, WY, USA Geologic reservoirs for managing carbon emissions (mostly CO2) have expanded over the last 5 years to include unconventional formations including basalts and fractured shales. Recently, ~1000 metric tons of CO2 was injected into the Columbia River Basalt (CRB) in Eastern Washington as part of the Wallula Pilot Project, Big Sky Regional Carbon Partnership. Based on reservoir conditions, the injected CO2 is present as a supercritical fluid that dissolves into the formation water over time, and reacts with basalt components to form carbonate minerals. In this paper, we discuss mineral transformation reactions occurring when the forsterite (Mg2SiO4) is exposed to wet scCO2 in equilibrium with pure water and sodium citrate solutions. Forsterite was selected as it is an important olivine group mineral present in igneous and mafic rocks. Citrate was selected as it has been shown to enhance mineral dissolution and organic ligands are possible degradation products of the microbial communities present in the formational waters of the CRB. For the supercritical phase, transformation reactions were examined by in situ high pressure x-ray diffraction (HXRD) in the presence of supercritical carbon dioxide (scCO2) in contact with water and sodium citrate solutions at conditions relevant to carbon sequestration. Experimental results show close-to-complete dissolution of forsterite in contact with scCO2 equilibrated with pure water for 90 hours (90 bar and 50°C). Under these conditions, thin films of water coated the mineral surface, providing a mechanism for silicate dissolution and transport of cations necessary for carbonate formation. The primary crystalline component initially detected with in situ HXRD was the hydrated magnesium carbonate, nesquehonite [Mg

  11. CO2 deserts: implications of existing CO2 supply limitations for carbon management.

    Science.gov (United States)

    Middleton, Richard S; Clarens, Andres F; Liu, Xiaowei; Bielicki, Jeffrey M; Levine, Jonathan S

    2014-10-01

    Efforts to mitigate the impacts of climate change will require deep reductions in anthropogenic CO2 emissions on the scale of gigatonnes per year. CO2 capture and utilization and/or storage technologies are a class of approaches that can substantially reduce CO2 emissions. Even though examples of this approach, such as CO2-enhanced oil recovery, are already being practiced on a scale >0.05 Gt/year, little attention has been focused on the supply of CO2 for these projects. Here, facility-scale data newly collected by the U.S. Environmental Protection Agency was processed to produce the first comprehensive map of CO2 sources from industrial sectors currently supplying CO2 in the United States. Collectively these sources produce 0.16 Gt/year, but the data reveal the presence of large areas without access to CO2 at an industrially relevant scale (>25 kt/year). Even though some facilities with the capability to capture CO2 are not doing so and in some regions pipeline networks are being built to link CO2 sources and sinks, much of the country exists in "CO2 deserts". A life cycle analysis of the sources reveals that the predominant source of CO2, dedicated wells, has the largest carbon footprint further confounding prospects for rational carbon management strategies. PMID:25137398

  12. CO2 Separation from Syngas by Multiwall Carbon Nanotube

    Directory of Open Access Journals (Sweden)

    Soodabeh Khalili

    2012-01-01

    Full Text Available In this study the equilibrium uptakes of hydrogen and carbon dioxid as the main constituents of syngas by the multi-walled carbon nanotube (MWCNT were investigated at the temperature range of 288-318 K and pressure up to 40 bars. The results have shown that temperature had much less effect on the adsorption of H2 on MWCNT than adsorption of CO2. Several model isotherms such as Langmuir and Freundlich were examined to fit the equilibrium uptake data. The kinetics of H2 and CO2 adsorption on MWCNT were also investigated and the results revealed a fast sorption kinetic for both gas adsorption on MWCNT. Isosteric heat of adsorption was evaluated based on the Clausius–Clapeyron equation at different temperatures. Small values of isosteric heat of adsorption confirmed that although the adsorption of H2 and CO2 on MWCNT were exothermic, but the heat of adsorption was too low, therefore the process of adsorption of both gases on the MWCNT used in this study is physisorption.

  13. Development of a carbonate absorption-based process for post-combustion CO2 capture: The role of biocatalyst to promote CO2 absorption rate

    Science.gov (United States)

    Lu, Y.; Ye, X.; Zhang, Z.; Khodayari, A.; Djukadi, T.

    2011-01-01

    An Integrated Vacuum Carbonate Absorption Process (IVCAP) for post-combustion carbon dioxide (CO2) capture is described. IVCAP employs potassium carbonate (PC) as a solvent, uses waste or low quality steam from the power plant for CO2 stripping, and employs a biocatalyst, carbonic anhydrase (CA) enzyme, for promoting the CO2 absorption into PC solution. A series of experiments were performed to evaluate the activity of CA enzyme mixed in PC solutions in a stirred tank reactor system under various temperatures, CA dosages, CO2 loadings, CO2 partial pressures, and the presence of major flue gas contaminants. It was demonstrated that CA enzyme is an effective biocatalyst for CO2 absorption under IVCAP conditions. ?? 2011 Published by Elsevier Ltd.

  14. CO2 Capture by Carbon Aerogel–Potassium Carbonate Nanocomposites

    OpenAIRE

    Guang Yang; Hongchao Luo; Tomonori Ohba; Hirofumi Kanoh

    2016-01-01

    Recently, various composites for reducing CO2 emissions have been extensively studied. Because of their high sorption capacity and low cost, alkali metal carbonates are recognized as a potential candidate to capture CO2 from flue gas under moist conditions. However, undesirable effects and characteristics such as high regeneration temperatures or the formation of byproducts lead to high energy costs associated with the desorption process and impede the application of these materials. In this ...

  15. Can Producing Oil Store Carbon? Greenhouse Gas Footprint of CO2EOR, Offshore North Sea.

    Science.gov (United States)

    Stewart, R Jamie; Haszeldine, R Stuart

    2015-05-01

    Carbon dioxide enhanced oil recovery (CO2EOR) is a proven and available technology used to produce incremental oil from depleted fields while permanently storing large tonnages of injected CO2. Although this technology has been used successfully onshore in North America and Europe, there are currently no CO2EOR projects in the United Kingdom. Here, we examine whether offshore CO2EOR can store more CO2 than onshore projects traditionally have and whether CO2 storage can offset additional emissions produced through offshore operations and incremental oil production. Using a high-level Life Cycle system approach, we find that the largest contribution to offshore emissions is from flaring or venting of reproduced CH4 and CO2. These can already be greatly reduced by regulation. If CO2 injection is continued after oil production has been optimized, then offshore CO2EOR has the potential to be carbon negative--even when emissions from refining, transport, and combustion of produced crude oil are included. The carbon intensity of oil produced can be just 0.056-0.062 tCO2e/bbl if flaring/venting is reduced by regulation. This compares against conventional Saudi oil 0.040 tCO2e/bbl or mined shale oil >0.300 tCO2e/bbl. PMID:25789442

  16. Determination of carbon-14 environmental samples by mixing 14CO2 with a liquid scintillator

    International Nuclear Information System (INIS)

    A method for the determination of Carbon-14 (14CO2) in environmental samples has been developed. The method use the direct absorption of the carbon dioxide into Carbosorb, followed with incorporation of the mixture (Carbosorb-CO2) to the liquid scintillator. The results obtained to apply this method and the benzene synthesis, usual in our laboratory, are discused and compared. The method of collection of atmospheric samples is also described. (Author)

  17. Geologic Carbon Sequestration: Mitigating Climate Change by Injecting CO2 Underground (LBNL Summer Lecture Series)

    Energy Technology Data Exchange (ETDEWEB)

    Oldenburg, Curtis M [LBNL Earth Sciences Division

    2009-07-21

    Summer Lecture Series 2009: Climate change provides strong motivation to reduce CO2 emissions from the burning of fossil fuels. Carbon dioxide capture and storage involves the capture, compression, and transport of CO2 to geologically favorable areas, where its injected into porous rock more than one kilometer underground for permanent storage. Oldenburg, who heads Berkeley Labs Geologic Carbon Sequestration Program, will focus on the challenges, opportunities, and research needs of this innovative technology.

  18. Determination of Carbon-14 in environmental samples by mixing 14CO2 with a liquid scintillator

    International Nuclear Information System (INIS)

    A method for the determination of Carbon-14 (14CO2) in environmental samples has been developed. The method use the direct absorption of the carbon dioxide into Carbosorb, followed with incorporation of the mixture (Carbosorb-CO2) to the liquid scintillator. The results obtained to apply this method and the benzene synthesis, usual in our laboratory, are discussed and compared. The method of collection of atmospheric samples is also described. (Author) 10 refs

  19. High sensitivity CW-Cavity Ring Down Spectroscopy of five 13CO2 isotopologues of carbon dioxide in the 1.26-1.44 μm region (I): Line positions

    International Nuclear Information System (INIS)

    The absorption spectrum of highly enriched 13C carbon dioxide has been investigated by CW-Cavity Ring Down Spectroscopy with a setup based on fibered distributed feedback (DFB) laser diodes. By using a series of 30 DFB lasers, the CO2 spectrum was recorded in the 7029-7917 cm-1 region with a typical sensitivity of 3x10-10 cm-1. The uncertainty on the determined line positions is on the order of 8x10-4 cm-1. More than 3800 transitions with intensities as low as 1x10-29 cm/molecule were detected and assigned to the 13C16O2, 16O13C17O, 16O13C18O, 17O13C18O and 13C18O2 isotopologues. For comparison, only 104 line positions of 13C16O2 were previously reported in the literature in the considered region. The band-by-band analysis has led to the determination of the rovibrational parameters of a total of 83 bands including 56 bands of the 13C16O2 species. The measured line positions of 13C16O2 and 16O13C18O were found in good agreement with the predictions of the respective effective Hamiltonian (EH) models but the agreement degrades for the minor isotopologues. Several cases of resonance interactions were found and discussed. In the 20033-10002 band of 13C16O2, an anharmonic resonance interaction leads to deviations on the order of 0.05 cm-1 compared to the EH predictions. The existence of interpolyad interactions affecting the non-symmetric isotopologues of carbon dioxide is confirmed by the observation of two occurrences in 16O13C17O and 16O13C18O. The obtained results improve significantly the knowledge of the spectroscopy of the 13C isotopologues of carbon dioxide. They will be valuable to refine the sets of effective Hamiltonian parameters used to generate the CDSD database.

  20. Isotopic composition of atmospheric CO2 inferred from carbon in C4 plant cellulose

    International Nuclear Information System (INIS)

    The isotopic composition of atmospheric carbon dioxide provides an important constraint for models of the global carbon cycle. It is shown that carbon in C4 plants preserves an isotopic record of the CO2 used in photosynthesis. Data for the maize plant Zea mays yield results for the isotopic composition of atmospheric CO2 consistent with measurements of modern air and air trapped in polar ice. Data from C4 plants may thus be used to extend the isotopic record of atmospheric CO2 into the past, complementing data from other sources. (author)

  1. Fractionation of Peppermint Essential Oil by Supercritical Carbon Dioxide%超临界CO2精密分离技术提纯薄荷脑

    Institute of Scientific and Technical Information of China (English)

    程健; 王存文; 丁一刚; 柏正武; 李世荣; 俞发全; 吴元欣

    2005-01-01

    进行了利用超临界CO2精密分离技术从薄荷原油中提纯薄荷脑的研究,分别考察了分馏塔温度梯度、升压速率等操作参数对分离效果的影响.结果表明,分离精馏塔内形成一定的温度梯度或在一定的温度梯度下改变升压速度都可以有效改善分离效果,当塔内温度梯度为20℃、升压速率为0.1 MPa·(15 min)-1时,ω(薄荷脑)>90%,产物产率为80%;对ω(薄荷脑)=90%的产品进行二次分离,可获得ω(薄荷脑)=99.9%的产物.

  2. 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.

  3. The Diagnostic Value of End-tidal Carbon Dioxide (EtCO2 and Alveolar Dead Space (AVDS in Patients with Suspected Pulmonary Thrombo-embolism (PTE

    Directory of Open Access Journals (Sweden)

    Reza Basiri

    2015-06-01

    Full Text Available Introduction: Capnography, is an easy, fast and practical method which its application in the diagnosis of Pulmonary Thromboendarterectomy (PTE has recently been studied. This study aimed to assess the diagnostic value of end-tidal CO2 (ETCO2 and the alveolar dead space (AVDS in the diagnosis of patients suspected to PTE who have been referred to the emergency department. Materials and Methods: This cross-sectional study was conducted during one year in the emergency department of Ghaem Hospital on patients with suspected PTE who scored less than 4 for the Wells’ criteria during the initial evaluation. After excluding other differential diagnoses, all patients underwent CT pulmonary angiography (CTPA to confirm PTE. Following that, arterial blood gas sampling, ETCO2 and AVDS were requested for all the patients based on capnography. Data analysis was performed using descriptive statistical tests in SPSS software version 11.5. The sensitivity, specificity, and positive and negative predictive values of AVDS and ETCO2 were measured based on (CTPA results. Results: The study was performed on 78 patients (mean age of 47.08± 15.6 years, 43 males/35 females suspected to PTE. According to the results of CTPA, 37 patients did not develop PTE while 41 patients were with PTE. There was no significant difference between the two groups in terms of age and gender (P=0.999, while a statistically significant difference was found between the mean values of ETCO2 and AVDS between the two groups (P

  4. Carbon dioxide in vascular imaging and intervention.

    Science.gov (United States)

    Yang, X; Manninen, H; Soimakallio, S

    1995-07-01

    Angiography with iodinated contrast agents is bound up with the risks of contrast-induced nephrotoxicity and hypersensitivity, which led to the idea of using carbon dioxide (CO2) gas as a negative contrast medium to eliminate these drawbacks. During the last decade, refinements and experiences have proved carbon dioxide digital subtraction angiography (CO2-DSA) to be an accurate, safe, and clinically promising vascular imaging modality, with the advantages of no hypersensitivity and no nephrotoxicity as well as minimal patient discomfort. In this article, we have reviewed the history, physical and chemical aspects, techniques, and pathophysiologic changes with the use of CO2-DSA as well as some clinical trials. Applications of CO2 gas in vascular interventions and other imagings, and the advantages and limitations of using CO2 gas in DSA are also discussed. PMID:7619608

  5. Carbon dioxide in vascular imaging and intervention

    International Nuclear Information System (INIS)

    Angiography with iodinated contrast agents is bound up with the risks of contrast-induced nephrotoxicity and hypersensitivity, which led to the idea of using carbon dioxide (CO2) gas as a negative contrast medium to eliminate these drawbacks. During the last decade, refinements and experiences have proved carbon dioxide digital subtraction angiography (CO2-DSA) to be an accurate, safe, and clinically promising vascular imaging modality, with the advantages of no hypersensitivity and no nephrotoxicity as well as minimal patient discomfort. In this article, we have reviewed the history, physical and chemical aspects, techniques, and pathophysiologic changes with the use of CO2-DSA as well as some clinical trials. Applications of CO2 gas in vascular interventions and other imagings, and the advantages and limitations of using CO2 gas in DSA are also discussed. (orig.)

  6. Carbon Dioxide Fountain

    Science.gov (United States)

    Kang, Seong-Joo; Ryu, Eun-Hee

    2007-01-01

    This article presents the development of a carbon dioxide fountain. The advantages of the carbon dioxide fountain are that it is odorless and uses consumer chemicals. This experiment also is a nice visual experiment that allows students to see evidence of a gaseous reagent being consumed when a pressure sensor is available. (Contains 3 figures.)…

  7. Accelerated carbonation of steel slags using CO2 diluted sources: CO2 uptakes and energy requirements

    Directory of Open Access Journals (Sweden)

    Renato eBaciocchi

    2016-01-01

    Full Text Available This work presents the results of carbonation experiments performed on Basic Oxygen Furnace (BOF steel slag samples employing gas mixtures containing 40 and 10% CO2 vol. simulating the gaseous effluents of gasification and combustion processes respectively, as well as 100% CO2 for comparison purposes. Two routes were tested, the slurry phase (L/S=5 l/kg, T=100 °C and Ptot=10 bar and the thin film (L/S =0.3-0.4 l/kg, T=50 °C and Ptot=7-10 bar routes. For each one, the CO2 uptake achieved as a function of the reaction time was analyzed and on this basis the energy requirements associated to each carbonation route and gas mixture composition were estimated considering to store the CO2 emissions of a medium size natural gas fired power plant (20 MW. For the slurry phase route, maximum CO2 uptakes ranged from around 8% at 10% CO2, to 21.1% (BOF-a and 29.2% (BOF-b at 40% CO2 and 32.5% (BOF-a and 40.3% (BOF-b at 100% CO2. For the thin film route, maximum uptakes of 13% (BOF-c and 19.5% (BOF-d at 40% CO2, and 17.8% (BOF-c and 20.2% (BOF-d at 100% were attained. The energy requirements of the two analyzed process routes appeared to depend chiefly on the CO2 uptake of the slag. For both process route, the minimum overall energy requirements were found for the tests with 40% CO2 flows (i.e. 1400-1600 MJ/t CO2 for the slurry phase and 2220-2550 MJ/t CO2 for the thin film route.

  8. 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...

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

    DEFF Research Database (Denmark)

    Selsted, M.B.; Ambus, P.; Michelsen, A.;

    2011-01-01

    Carbon dioxide (CO(2)) 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 CO(2) concentration from c. 380 mu...

  10. Silicate Carbonation Processes in Water-Bearing Supercritical CO2 Fluids: Implications for Geologic Carbon Sequestration

    Science.gov (United States)

    Miller, Q. R.; Schaef, T.; Thompson, C.; Loring, J. S.; Windisch, C. F.; Bowden, M. E.; Arey, B. W.; McGrail, P.

    2012-12-01

    Global climate change is viewed by many as an anthropogenic phenomenon that could be mitigated through a combination of conservation efforts, alternative energy sources, and the development of technologies capable of reducing carbon dioxide (CO2) emissions. Continued increases of atmospheric CO2 concentrations are projected over the next decade, due to developing nations and growing populations. One economically favorable option for managing CO2 involves subsurface storage in deep basalt formations. The silicate minerals and glassy mesostasis basalt components act as metal cation sources, reacting with the CO2 to form carbonate minerals. Most prior work on mineral reactivity in geologic carbon sequestration settings involves only aqueous dominated reactions. However, in most sequestration scenarios, injected CO2 will reside as a buoyant fluid in contact with the sealing formation (caprock) and slowly become water bearing. Comparatively little laboratory research has been conducted on reactions occurring between minerals in the host rock and the wet scCO2. In this work, we studied the carbonation of wollastonite [CaSiO3] exposed to variably wet supercritical CO2 (scCO2) at a range of temperatures (50, 55 and 70 °C) and pressures (90,120 and 160 bar) in order to gain insight into reaction processes. Mineral transformation reactions were followed by two novel in situ high pressure techniques, including x-ray diffraction that tracked the rate and extents of wollastonite conversion to calcite. Increased dissolved water concentrations in the scCO2 resulted in increased carbonation approaching ~50 wt. %. Development of thin water films on the mineral surface were directly observed with infrared (IR) spectroscopy and indirectly with 18O isotopic labeling techniques (Raman spectroscopy). The thin water films were determined to be critical for facilitating carbonation processes in wet scCO2. Even in extreme low water conditions, the IR technique detected the formation of

  11. NEW CATALYTIC SYSTEMS FOR THE FIXATION OF CO2 Ⅲ. INFLUENCE OF ADDITIVES AND REACTION MEDIUM ON THE COPOLYMERIZATION OF CARBON DIOXIDE-EPICHLOROHYDRIN IN THE PRESENCE OF Nd(P204)3-Al(i-Bu)3

    Institute of Scientific and Technical Information of China (English)

    CHEN Xianhai; ZHANG Yifeng; SHEN Zhiquan

    1994-01-01

    Copolymerization of carbon dioxide with epichlorohydrin was successfully carried out by using Nd (P204)3-A1 (i-Bu)3 as catalyst (P204) = (RO)2POO -, R=CH3 (CH2)3CH(C2H5)CH2-). Addition of carbonyl compounds into the catalyst decreased the carbon dioxide content of the copolymer to some extent. Compared to nonpolar solvents, ethereal and moderate polar solvents were favourable to obtaining higher carbon dioxide content copolymer. The coincidence of these results with the assumed copolymerization scheme clearly indicated that the copolymerization proceeds via coordinate anionic mechanism.

  12. Bench-to-bedside review: Carbon dioxide

    OpenAIRE

    Curley, Gerard; Laffey, John G; Kavanagh, Brian P.

    2010-01-01

    Carbon dioxide is a waste product of aerobic cellular respiration in all aerobic life forms. PaCO2 represents the balance between the carbon dioxide produced and that eliminated. Hypocapnia remains a common - and generally underappreciated - component of many disease states, including early asthma, high-altitude pulmonary edema, and acute lung injury. Induction of hypocapnia remains a common, if controversial, practice in both adults and children with acute brain injury. In contrast, hypercap...

  13. Surface circulation patterns and the pathways of sea surface carbon dioxide (CO2 off northern Chile (~27.5° S between 30 and 10 kyr BP: global and/or local forcing?

    Directory of Open Access Journals (Sweden)

    R. Torres

    2010-03-01

    Full Text Available We present a reconstruction of past changes in partial pressure of CO2 (pCO2 from northern Chile (~27° S, between 10 and 30 kyr BP, based on carbon isotope composition of C37:2-alkenone. The high-pCO2 during the entire time series indicates that northern Chile upwelling system has been a permanent source of CO2 to the atmosphere. The multiproxy reconstruction suggests that the CO2 outgassing and sequestration pathways were modulated by local and global mechanisms. During global glacial conditions, an enhanced coastal upwelling forcing resulted in high-availability of deep water macronutrients and a CO2-supersaturated water column, which combined with high-inputs of iron from the continent, intensified the carbon sequestration pathway of the biological pump, through diatom biomass export. During the deglacial, a decrease in the upwelling forcing, an increment in water column stability and reduced continental inputs of iron are consistent with a larger role of calcifying organisms in the plankton assemblage in terms of carbon sequestration pathway through the carbonate system.

  14. The carbon dioxide capture and geological storage

    International Nuclear Information System (INIS)

    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 CO2 generated by the greenhouse gases emission in order to stabilize atmospheric concentrations. This sheet presents the CO2 capture from lage fossil-fueled combustion installations, the three capture techniques and the CO2 transport options, the geological storage of the CO2 and Total commitments in the domain. (A.L.B.)

  15. Carbon dioxide detection in adult Odonata.

    Science.gov (United States)

    Piersanti, Silvana; Frati, Francesca; Rebora, Manuela; Salerno, Gianandrea

    2016-04-01

    The present paper shows, by means of single-cell recordings, responses of antennal sensory neurons of the damselfly Ischnura elegans when stimulated by air streams at different CO2 concentrations. Unlike most insects, but similarly to termites, centipedes and ticks, Odonata possess sensory neurons strongly inhibited by CO2, with the magnitude of the off-response depending upon the CO2 concentration. The Odonata antennal sensory neurons responding to CO2 are also sensitive to airborne odors; in particular, the impulse frequency is increased by isoamylamine and decreased by heptanoic and pentanoic acid. Further behavioral investigations are necessary to assign a biological role to carbon dioxide detection in Odonata. PMID:26831359

  16. Forest soil carbon oxidation state and oxidative ratio responses to elevated CO2

    Science.gov (United States)

    Hockaday, William C.; Gallagher, Morgan E.; Masiello, Caroline A.; Baldock, Jeffrey A.; Iversen, Colleen M.; Norby, Richard J.

    2015-09-01

    The oxidative ratio (OR) of the biosphere is the stoichiometric ratio (O2/CO2) of gas exchange by photosynthesis and respiration—a key parameter in budgeting calculations of the land and ocean carbon sinks. Carbon cycle-climate feedbacks could alter the OR of the biosphere by affecting the quantity and quality of organic matter in plant biomass and soil carbon pools. This study considers the effect of elevated atmospheric carbon dioxide concentrations ([CO2]) on the OR of a hardwood forest after nine growing seasons of Free-Air CO2 Enrichment. We measured changes in the carbon oxidation state (Cox) of biomass and soil carbon pools as a proxy for the ecosystem OR. The OR of net primary production, 1.039, was not affected by elevated [CO2]. However, the Cox of the soil carbon pool was 40% higher at elevated [CO2], and the estimated OR values for soil respiration increased from 1.006 at ambient [CO2] to 1.054 at elevated [CO2]. A biochemical inventory of the soil organic matter ascribed the increases in Cox and OR to faster turnover of reduced substrates, lignin and lipids, at elevated [CO2]. This implicates the heterotrophic soil community response to elevated [CO2] as a driver of disequilibrium in the ecosystem OR. The oxidation of soil carbon pool constitutes an unexpected terrestrial O2 sink. Carbon budgets constructed under the assumption of OR equilibrium would equate such a terrestrial O2 sink to CO2 uptake by the ocean. The potential for climate-driven disequilibriua in the cycling of O2 and CO2 warrants further investigation.

  17. CO2 Capture by Carbon Aerogel–Potassium Carbonate Nanocomposites

    Directory of Open Access Journals (Sweden)

    Guang Yang

    2016-01-01

    Full Text Available Recently, various composites for reducing CO2 emissions have been extensively studied. Because of their high sorption capacity and low cost, alkali metal carbonates are recognized as a potential candidate to capture CO2 from flue gas under moist conditions. However, undesirable effects and characteristics such as high regeneration temperatures or the formation of byproducts lead to high energy costs associated with the desorption process and impede the application of these materials. In this study, we focused on the regeneration temperature of carbon aerogel–potassium carbonate (CA–KC nanocomposites, where KC nanocrystals were formed in the mesopores of the CAs. We observed that the nanopore size of the original CA plays an important role in decreasing the regeneration temperature and in enhancing the CO2 capture capacity. In particular, 7CA–KC, which was prepared from a CA with 7 nm pores, exhibited excellent performance, reducing the desorption temperature to 380 K and exhibiting a high CO2 capture capacity of 13.0 mmol/g-K2CO3, which is higher than the theoretical value for K2CO3 under moist conditions.

  18. Sustainable catalyst supports for carbon dioxide gas adsorbent

    Science.gov (United States)

    Mazlee, M. N.

    2016-07-01

    The adsorption of carbon dioxide (CO2) become the prime attention nowadays due to the fact that increasing CO2 emissions has been identified as a contributor to global climate change. Major sources of CO2 emissions are thermoelectric power plants and industrial plants which account for approximately 45% of global CO2 emissions. Therefore, it is an urgent need to develop an efficient CO2 reduction technology such as carbon capture and storage (CCS) that can reduce CO2 emissions particularly from the energy sector. A lot of sustainable catalyst supports have been developed particularly for CO2 gas adsorbent applications.

  19. Phenol-Formaldehyde Resin-Based Carbons for CO2 Separation at Sub-Atmospheric Pressures

    Directory of Open Access Journals (Sweden)

    Noelia Álvarez-Gutiérrez

    2016-03-01

    Full Text Available The challenge of developing effective separation and purification technologies that leave much smaller energy footprints is greater for carbon dioxide (CO2 than for other gases. In addition to its involvement in climate change, CO2 is present as an impurity in biogas and bio-hydrogen (biological production by dark fermentation, in post-combustion processes (flue gas, CO2-N2 and many other gas streams. Selected phenol-formaldehyde resin-based activated carbons prepared in our laboratory have been evaluated under static conditions (adsorption isotherms as potential adsorbents for CO2 separation at sub-atmospheric pressures, i.e., in post-combustion processes or from biogas and bio-hydrogen streams. CO2, H2, N2, and CH4 adsorption isotherms at 25 °C and up to 100 kPa were obtained using a volumetric equipment and were correlated by applying the Sips model. Adsorption equilibrium was then predicted for multicomponent gas mixtures by extending the multicomponent Sips model and the Ideal Adsorbed Solution Theory (IAST in conjunction with the Sips model. The CO2 uptakes of the resin-derived carbons from CO2-CH4, CO2-H2, and CO2-N2 at atmospheric pressure were greater than those of the reference commercial carbon (Calgon BPL. The performance of the resin-derived carbons in terms of equilibrium of adsorption seems therefore relevant to CO2 separation in post-combustion (flue gas, CO2-N2 and in hydrogen fermentation (CO2-H2, CO2-CH4.

  20. Algal-based CO2 Sequestration Technology and Global Scenario of Carbon Credit Market: A Review

    Directory of Open Access Journals (Sweden)

    Shailendra Kumar Singh

    2016-08-01

    Full Text Available The objective of this paper is to provide an overview of the global and national scenario of Carbon credit. This paper will also discuss the advantages of the algae-based carbon capture technology in growing carbon credit market. Carbon Dioxide (CO2, the most important greenhouse gas produced by combustion of fuels, has become a cause of global panic as its concentration in the Earth’s atmosphere has been rising alarmingly. However, it is now turning into a product that helps people, countries, consultants, traders, corporations and even farmers earn billion of rupees. A carbon credit is a generic term for any tradable certificate or permit representing the right to emit one tone of CO2 or CO2 equivalent (CO2-e. Businesses can exchange, buy or sell carbon credits in the international markets at the prevailing market price. India and China are likely to emerge as biggest seller and Europe is going to be biggest buyers of carbon credits. Using algae for reduction the CO2 concentration in the atmosphere is known as algae-based carbon capture technology. This new technology has attracted companies that need inexpensive CO2 sequestration solutions. Algae farming emerge as the best CO2 sequestration technique in comparison with other methods.

  1. Alteration of forest succession and carbon cycling under elevated CO2.

    Science.gov (United States)

    Miller, Adam D; Dietze, Michael C; DeLucia, Evan H; Anderson-Teixeira, Kristina J

    2016-01-01

    Regenerating forests influence the global carbon (C) cycle, and understanding how climate change will affect patterns of regeneration and C storage is necessary to predict the rate of atmospheric carbon dioxide (CO2 ) increase in future decades. While experimental elevation of CO2 has revealed that young forests respond with increased productivity, there remains considerable uncertainty as to how the long-term dynamics of forest regrowth are shaped by elevated CO2 (eCO2 ). Here, we use the mechanistic size- and age- structured Ecosystem Demography model to investigate the effects of CO2 enrichment on forest regeneration, using data from the Duke Forest Free-Air Carbon dioxide Enrichment (FACE) experiment, a forest chronosequence, and an eddy-covariance tower for model parameterization and evaluation. We find that the dynamics of forest regeneration are accelerated, and stands consistently hit a variety of developmental benchmarks earlier under eCO2 . Because responses to eCO2 varied by plant functional type, successional pathways, and mature forest composition differed under eCO2 , with mid- and late-successional hardwood functional types experiencing greater increases in biomass compared to early-successional functional types and the pine canopy. Over the simulation period, eCO2 led to an increase in total ecosystem C storage of 9.7 Mg C ha(-1) . Model predictions of mature forest biomass and ecosystem-atmosphere exchange of CO2 and H2 O were sensitive to assumptions about nitrogen limitation; both the magnitude and persistence of the ecosystem response to eCO2 were reduced under N limitation. In summary, our simulations demonstrate that eCO2 can result in a general acceleration of forest regeneration while altering the course of successional change and having a lasting impact on forest ecosystems. PMID:26316364

  2. Temperature dependence of the relationship between pCO2 and dissolved organic carbon in lakes

    KAUST Repository

    Pinho, L.

    2016-02-15

    The relationship between the partial pressure of carbon dioxide (pCO2) and dissolved organic carbon (DOC) concentration in Brazilian lakes, encompassing 225 samples across a wide latitudinal range in the tropics, was tested. Unlike the positive relationship reported for lake waters, which was largely based on temperate lakes, we found no significant relationship for low-latitude lakes (< 33°), despite very broad ranges in both pCO2 and DOC levels. These results suggest substantial differences in the carbon cycling of low-latitude lakes, which must be considered when upscaling limnetic carbon cycling to global scales.

  3. Carbon Dioxide, a Solvent and Synthon for Green Chemistry

    OpenAIRE

    Ballivet-Tkatchenko, D.; Camy, Séverine; Condoret, Jean-Stéphane

    2005-01-01

    Carbon dioxide is a renewable resource of carbon when we consider the reuse of existing CO2 as a carbon source for producing chemicals. The development of new applications is of major interest from the point of view of carbon dioxide sequestration and within the scope of green chemistry. For example, using CO2 instead of CO or COCl2 for chemical synthesis constitutes an attractive alternative avoiding hazardous and toxic reactants. However, it has the lowest chemical reactivity, which i...

  4. Method for carbon dioxide sequestration

    Science.gov (United States)

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

    2015-09-22

    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) 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. This process allows for the immobilization of the injected SC--CO.sub.2 for very long times. The dispersal of scCO2 into small ganglia is accomplished by alternating injection of SC--CO.sub.2 and water. The injection rate is required to be high enough to ensure the SC--CO.sub.2 at the advancing front to be broken into pieces and small enough for immobilization through viscous instability.

  5. EFFECTS OF CO2 AND O3 ON CARBON FLUX FOR PONDEROSA PINE PLANT/LITTER/SOIL SYSTEM

    Science.gov (United States)

    Carbon dioxide (CO2), a main contributor to global climate change, also adds carbon to forests. In contrast, tropospheric ozone (O3) can reduce carbon uptake and increase carbon loss by forests. Thus, the net balance of carbon uptake and loss for forests can be affected by concu...

  6. Real-World Carbon Dioxide Impacts of Traffic Congestion

    OpenAIRE

    Barth, Matthew; Boriboonsomsin, Kanok

    2010-01-01

    Transportation plays a significant role in carbon dioxide (CO2) emissions, accounting for approximately a third of the U.S. inventory. To reduce CO2 emissions in the future, transportation policy makers are planning on making vehicles more efficient and increasing the use of carbon-neutral alternative fuels. In addition, CO2 emissions can be lowered by improving traffic operations, specifically through the reduction of traffic congestion. Traffic congestion and its impact on CO2 emissions wer...

  7. Polyurethane Foam-Based Ultramicroporous Carbons for CO2 Capture.

    Science.gov (United States)

    Ge, Chao; Song, Jian; Qin, Zhangfeng; Wang, Jianguo; Fan, Weibin

    2016-07-27

    A series of sustainable porous carbon materials were prepared from waste polyurethane foam and investigated for capture of CO2. The effects of preparation conditions, such as precarbonization, KOH to carbon precursor weight ratio, and activation temperature, on the porous structure and CO2 adsorption properties were studied for the purpose of controlling pore sizes and nitrogen content and developing high-performance materials for capture of CO2. The sample prepared at optimum conditions shows CO2 adsorption capacities of 6.67 and 4.33 mmol·g(-1) at 0 and 25 °C under 1 bar, respectively, which are comparable to those of the best reported porous carbons prepared from waste materials. The HCl treatment experiment reveals that about 80% of CO2 adsorption capacity arises from physical adsorption, while the other 20% is due to the chemical adsorption originated from the interaction of basic N groups and CO2 molecules. The relationship between CO2 uptake and pore size at different temperatures indicates that the micropores with pore size smaller than 0.86 and 0.70 nm play a dominant role in the CO2 adsorption at 0 and 25 °C, respectively. It was found that the obtained carbon materials exhibited high recyclability and high selectivity to adsorption of CO2 from the CO2 and N2 mixture. PMID:27376177

  8. Accelerated carbonation of steel slags using CO2 diluted sources: CO2 uptakes and energy requirements

    OpenAIRE

    Renato eBaciocchi; Giulia eCosta; Alessandra ePolettini; Raffaella ePomi; Alessio eStramazzo; Daniela eZingaretti

    2016-01-01

    This work presents the results of carbonation experiments performed on Basic Oxygen Furnace (BOF) steel slag samples employing gas mixtures containing 40 and 10% CO2 vol. simulating the gaseous effluents of gasification and combustion processes respectively, as well as 100% CO2 for comparison purposes. Two routes were tested, the slurry phase (L/S=5 l/kg, T=100 °C and Ptot=10 bar) and the thin film (L/S =0.3-0.4 l/kg, T=50 °C and Ptot=7-10 bar) routes. For each one, the CO2 uptake achieved as...

  9. CO2 perturbation experiments: similarities and differences between dissolved inorganic carbon and total alkalinity manipulations

    Directory of Open Access Journals (Sweden)

    U. Riebesell

    2009-04-01

    Full Text Available Increasing atmospheric carbon dioxide (CO2 through human activities and invasion of anthropogenic CO2 into the surface ocean alters the seawater carbonate chemistry, increasing CO2 and bicarbonate (HCO3 at the expense of carbonate ion (CO32− concentrations. This redistribution in the dissolved inorganic carbon (DIC pool decreases pH and carbonate saturation state (Ω. Several of these components are considered potential key variables influencing calcium carbonate precipitation in marine calcifiers such as coccolithophores, foraminifera, corals, mollusks and echinoderms. In need for improved understanding of the sensitivities of marine organisms and ecosystems to CO2 induced ocean acidification (OA, experimental CO2 perturbation studies will continue to be a backbone in future OA research. This requires accurate carbonate system manipulations and well-controlled experimental setups. Here we describe and analyse the chemical changes involved in the two basic approaches for carbonate chemistry manipulation, i.e. changing DIC at constant total alkalinity (TA and changing TA at constant DIC. Furthermore, we briefly introduce several methods to experimentally manipulate DIC and TA. Finally, we examine responses obtained with both approaches using published results for the coccolithophore Emiliania huxleyi. We conclude that under most experimental conditions DIC or TA manipulations yield similar changes in all parameters of the carbonate system, which implies direct comparability of data obtained with the two basic approaches for CO2 perturbation.

  10. Monitoring CO2 sources and sinks from space : the Orbiting Carbon Observatory (OCO) Mission

    Science.gov (United States)

    Crisp, David

    2006-01-01

    NASA's Orbiting Carbon Observatory (OCO) will make the first space-based measurements of atmospheric carbon dioxide (CO2) with the precision, resolution, and coverage needed to characterize the geographic distribution of CO2 sources and sinks and quantify their variability over the seasonal cycle. OCO is currently scheduled for launch in 2008. The observatory will carry a single instrument that incorporates three high-resolution grating spectrometers designed to measure the near-infrared absorption by CO2 and molecular oxygen (O2) in reflected sunlight. OCO will fly 12 minutes ahead of the EOS Aqua platform in the Earth Observing System (EOS) Afternoon Constellation (A-Train). The in-strument will collect 12 to 24 soundings per second as the Observatory moves along its orbit track on the day side of the Earth. A small sampling footprint (sinks of CO2. This information could play an important role in monitoring the integrity of large scale CO2 sequestration projects.

  11. Monitoring CO2 sources and sinks from space : the Orbiting Carbon Observatory (OCO) Mission

    Science.gov (United States)

    Crisp, David

    2006-01-01

    NASA's Orbiting Carbon Observatory (OCO) will make the first space-based measurements of atmospheric carbon dioxide (CO2) with the precision, resolution, and coverage needed to characterize the geographic distribution of CO2 sources and sinks and quantify their variability over the seasonal cycle. OCO is currently scheduled for launch in 2008. The observatory will carry a single instrument that incorporates three high-resolution grating spectrometers designed to measure the near-infrared absorption by CO2 and molecular oxygen (O2) in reflected sunlight. OCO will fly 12 minutes ahead of the EOS Aqua platform in the Earth Observing System (EOS) Afternoon Constellation (A-Train). The in-strument will collect 12 to 24 soundings per second as the Observatory moves along its orbit track on the day side of the Earth. A small sampling footprint (CO2. This information could play an important role in monitoring the integrity of large scale CO2 sequestration projects.

  12. Water Uptake and Carbon Assimilation in Maize at Elevated and ambient CO2: Modeling and Measurement.

    Science.gov (United States)

    Timlin, Dennis; Chun, Jong-Ahn; Kim, Soo-Hyung; Yang, Yang; Fleisher, David; Reddy, Vangimalla

    2013-04-01

    Potential transpiration in crops is dependent on both plant and environmental properties. Carbon dioxide content of the atmosphere is linked to potential transpiration because CO2 diffuses onto water saturated surfaces within plant stomata. At high CO2 concentrations, CO2 diffuses rapidly into stomata and therefore stomata do not have to remain open to the atmosphere for long periods of time. This results in lower transpiration rates per unit CO2 assimilated at elevated CO2 concentrations. The objective of this study was to measure CO2 assimilation and water uptake by maize under different irrigation regimes and two CO2 concentrations. The data were then used to evaluate the ability of the maize model MaizSim to simulate the effects of water stress and CO2 on water use and photosynthesis. MaizSim uses a Farquhar type photosynthesis model coupled a Ball-Berry stomatal control model. Non-linear beta functions are used to estimate the effects of temperature on growth and development processes. The experimental data come from experiments in outdoor, sunlit growth chambers at the USDA-ARS Beltsville Agricultural Research Center. The eight treatments comprised two levels of carbon dioxide concentrations (400 and 800 ppm) and four levels of water stress (well-watered control, mild, moderate, and severe). The water stress treatments were applied at both CO2 levels. Water contents were monitored hourly by a Time Domain Reflectometry (TDR) system. The model simulated higher water contents at the same time after applying water stress at the high CO2 treatment than for the low CO2 treatment as was found in the measured data. Measurement of water uptake by roots and carbon assimilation rates in the chambers will be addressed.

  13. 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...... delayed 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...

  14. Biochemical Capture and Removal of Carbon Dioxide

    Science.gov (United States)

    Trachtenberg, Michael C.

    1998-01-01

    We devised an enzyme-based facilitated transport membrane bioreactor system to selectively remove carbon dioxide (CO2) from the space station environment. We developed and expressed site-directed enzyme mutants for CO2 capture. Enzyme kinetics showed the mutants to be almost identical to the wild type save at higher pH. Both native enzyme and mutant enzymes were immobilized to different supports including nylons, glasses, sepharose, methacrylate, titanium and nickel. Mutant enzyme could be attached and removed from metal ligand supports and the supports reused at least five times. Membrane systems were constructed to test CO2 selectivity. These included proteic membranes, thin liquid films and enzyme-immobilized teflon membranes. Selectivity ratios of more than 200:1 were obtained for CO2 versus oxygen with CO2 at 0.1%. The data indicate that a membrane based bioreactor can be constructed which could bring CO2 levels close to Earth.

  15. Stable carbon isotope ratios as proxies for CO2 migration: An experimental approach with analogue fluids

    Science.gov (United States)

    Myrttinen, A.; Becker, V.; Mayer, B.; Barth, J. A.

    2012-12-01

    . The experiments were conducted on a supercritical pressure device at 60 bar and between 20 and 100 °C, where fluids containing baseline DIC concentrations of 10 mmol/L were allowed to react with injected CO2. First results from 20-hour experiments revealed carbon isotope fractionation between DIC and CO2 to range between 1.5 and 0.8 ‰ and pH values between about 5.5 and 6.5. These results indicate that isotope fractionation occurred between CO2 and a mixture of H2CO3 and HCO3-. We demonstrate that experimental investigations of carbon isotope effects in analogue fluids can provide important insights into the usefulness of isotopic tracers for field applications in CO2 migration monitoring at various subsurface conditions. The stable isotope tracer method has significant potential as an early detection method for CO2 leakage. References: Mook, W.G., Bommerson, J.C., Staverman, W.H., 1974. Carbon isotope fractionation between dissolved bicarbonate and gaseous carbon dioxide. Earth and Planetary Science Letters, 22(2): 169-176. Vogel, J.C., Grootes, P.M., Mook, W.G., 1970. Isotopic fractionation between gaseous and dissolved carbon dioxide. Zeitschrift für Physik, 230(3): 225-238.

  16. Turning carbon dioxide into fuel.

    Science.gov (United States)

    Jiang, Z; Xiao, T; Kuznetsov, V L; Edwards, P P

    2010-07-28

    Our present dependence on fossil fuels means that, as our demand for energy inevitably increases, so do emissions of greenhouse gases, most notably carbon dioxide (CO2). To avoid the obvious consequences on climate change, the concentration of such greenhouse gases in the atmosphere must be stabilized. But, as populations grow and economies develop, future demands now ensure that energy will be one of the defining issues of this century. This unique set of (coupled) challenges also means that science and engineering have a unique opportunity-and a burgeoning challenge-to apply their understanding to provide sustainable energy solutions. Integrated carbon capture and subsequent sequestration is generally advanced as the most promising option to tackle greenhouse gases in the short to medium term. Here, we provide a brief overview of an alternative mid- to long-term option, namely, the capture and conversion of CO2, to produce sustainable, synthetic hydrocarbon or carbonaceous fuels, most notably for transportation purposes. Basically, the approach centres on the concept of the large-scale re-use of CO2 released by human activity to produce synthetic fuels, and how this challenging approach could assume an important role in tackling the issue of global CO2 emissions. We highlight three possible strategies involving CO2 conversion by physico-chemical approaches: sustainable (or renewable) synthetic methanol, syngas production derived from flue gases from coal-, gas- or oil-fired electric power stations, and photochemical production of synthetic fuels. The use of CO2 to synthesize commodity chemicals is covered elsewhere (Arakawa et al. 2001 Chem. Rev. 101, 953-996); this review is focused on the possibilities for the conversion of CO2 to fuels. Although these three prototypical areas differ in their ultimate applications, the underpinning thermodynamic considerations centre on the conversion-and hence the utilization-of CO2. Here, we hope to illustrate that advances

  17. Supercritical CO 2 -philic nanoparticles suitable for determining the viability of carbon sequestration in shale

    KAUST Repository

    Xu, Yisheng

    2015-01-01

    © The Royal Society of Chemistry. A fracture spacing less than a decimeter is probably required for the successful sequestration of CO2 in shale. Tracer experiments using inert nanoparticles could determine if a fracturing this intense has been achieved. Here we describe the synthesis of supercritical CO2-philic nanoparticles suitable for this application. The nanoparticles are ~50 nm in diameter and consist of iron oxide (Fe3O4) and silica (SiO2) cores functionalized with a fluorescent polymeric corona. The nanoparticles stably disperse in supercritical carbon dioxide (scCO2) and are detectable to concentrations of 10 ppm. This journal is

  18. CO2 perturbation experiments: similarities and differences between dissolved inorganic carbon and total alkalinity manipulations

    Directory of Open Access Journals (Sweden)

    U. Riebesell

    2009-10-01

    Full Text Available Increasing atmospheric carbon dioxide (CO2 through human activities and invasion of anthropogenic CO2 into the surface ocean alters the seawater carbonate chemistry, increasing CO2 and bicarbonate (HCO3− at the expense of carbonate ion (CO32− concentrations. This redistribution in the dissolved inorganic carbon (DIC pool decreases pH and carbonate saturation state (Ω. Several components of the carbonate system are considered potential key variables influencing for instance calcium carbonate precipitation in marine calcifiers such as coccolithophores, foraminifera, corals, mollusks and echinoderms. Unravelling the sensitivities of marine organisms and ecosystems to CO2 induced ocean acidification (OA requires well-controlled experimental setups and accurate carbonate system manipulations. Here we describe and analyse the chemical changes involved in the two basic approaches for carbonate chemistry manipulation, i.e. changing DIC at constant total alkalinity (TA and changing TA at constant DIC. Furthermore, we briefly introduce several methods to experimentally manipulate DIC and TA. Finally, we examine responses obtained with both approaches using published results for the coccolithophore Emiliania huxleyi. We conclude that under most experimental conditions in the context of ocean acidification DIC and TA manipulations yield similar changes in all parameters of the carbonate system, which implies direct comparability of data obtained with the two basic approaches for CO2 perturbation.

  19. 生物质气化尾气CO2联合微波重整甲苯制备合成气%Toluene reforming by carbon dioxide recycled from biomass gasification into syngas production under microwave irradiation

    Institute of Scientific and Technical Information of China (English)

    李龙之; 宋占龙; 马春元; 王孚懋; 田原宇

    2014-01-01

    The quality of gaseous products can be deteriorated by tar, CO2 and other impurities during the process of biomass gasification. Based on the those impurities analysis, tar conversion by CO2 is performed in this paper. Toluene was chosen as a model compound in this study, and it was used for converting into syngas production over a biomass-derived char. Biomass char is obtained from the pyrolysis of corn straw at a microwave-assisted experimental system. The influences of heating method includes microwave heating (MH) and electrical heating (EH) as well as CO2 flow rate on toluene conversion, syngas yield and carbon loss. The results show that toluene conversion from microwave heating is significantly higher than that from electrical heating under the same circumstances. And it is revealed that a maximum difference of toluene conversion between microwave heating and electrical heating is reached up to 15.58%at CO2 flow rate of 80 mL/min. When a certain amount of CO2 is imported, toluene conversion can be improved effectively. The highest toluene conversion of 93.73%is achieved under microwave heating at CO2 flow rate of 80 mL/min, while toluene conversion under electrical heating is reached a peak of 82.13%, corresponding to CO2 flow rate of 40 mL/min. Moreover, the introduction of CO2 can regulate the conversion of toluene into syngas production with a suitable ratio of H2 and CO. At the same time, an excess of CO2 can result in a loss of carbon contained in biomass-derived char. The carbon consumed through the gasification of CO2 can be converted into part of syngas production, which can impose a direct contribution to total syngas yield. With the increase of CO2 flow rate, a higher syngas yield from carbon consumption is achieved. The maximum contribution of carbon consumption to syngas yield is 15.40% under microwave heating at CO2 flow rate of 120 mL/min. According to the results, it is found that the highest yield of syngas derived from toluene reforming by

  20. Soil fertility limits carbon sequestration by forest ecosystems in a CO2-enriched atmosphere

    International Nuclear Information System (INIS)

    Northern mid-latitude forests are a larger terrestrial carbon sink. Ignoring nutrient limitations, large increases in carbon sequestration from carbon dioxide (CO2) fertilization are expected in these forests. Yet, forests are usually relegated to sites of moderate to poor fertility, where tree growth is often limited by nutrient supply, in particular nitrogen. Here we present evidence that estimates of increases in carbon sequestration of forests, which is expected to partially compensate for increasing CO2 in the atmosphere, are unduly optimistic. In two forest experiments on maturing pines exposed to elevated atmospheric CO2, the CO2-induced biomass carbon increment without added nutrients was undetectable at a nutritionally poor site, and the stimulation at a nutritionally moderate site was transient, stabilizing at a marginal gain after three years. However, a large synergistic gain from higher CO2 and nutrients was detected with nutrients added. This gain was even larger at the poor site (threefold higher than the expected additive effect) than at the moderate site (twofold higher). Thus, fertility can restrain the response of wood carbon sequestration to increased atmospheric CO2. Assessment of future carbon sequestration should consider the limitations imposed by soil fertility, as well as interactions with nitrogen deposition. (author)

  1. 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.

  2. Carbon Turnover in a Crop Rotation Under Free Air CO2 Enrichment (FACE)

    Institute of Scientific and Technical Information of China (English)

    H. J. WEIGEL; K. LEWIN; J. NAGY; A. PACHOLSKI; S. BURKART; M. HELAL; O. HEINEMEYER; B. KLEIKAMP; R. MANDERSCHEID; C. FR(U)HAUF; G. F. HENDREY

    2005-01-01

    Mostly based on assumptions derived from controlled-environment studies, predicted future atmospheric CO2 concentrations [CO2] are expected to have considerable impacts on carbon (C) turnover in agro-ecosystems. In order to allow the in situ examination of C-transformations in the plant-soil system of arable crop rotations under future [CO2], a free air carbon dioxide enrichment (FACE) experiment (550 μmol mol-1 CO2) was started at Braunschweig, Germany in 1999.The crop rotation under investigation comprised winter barley, a cover crop (ryegrass), sugar beets and winter wheat.Assessments of CO2 effects included the determination of above- and belowground biomass production, measurements of canopy CO2- and H2O- fluxes, soil microbial biomass and in situ soil respiration. The results obtained during the 1st crop rotation cycle (3 years) showed that for the selected crops elevated [CO2] entailed significant positive effects (P<0.05) on aboveground (6%-14% stimulation) and belowground biomass production (up to 90% stimulation), while canopy evapotranspiration was reduced. This resulted in increased soil water content. Also, depending on crop type and season, high CO2 stimulated in situ soil respiration (up to 30%), while soil microbial biomass did not show significant respoases to elevated [CO2] during the first rotation cycle.

  3. Vapor-liquid equilibrium data for the carbon dioxide and nitrogen (CO2+N2) system at the temperatures 223, 270, 298 and 303 K and pressures up to 18 MPa

    OpenAIRE

    Westman, Snorre Foss; Stang, Hans Georg Jacob; Løvseth, Sigurd Weidemann; Austegard, Anders; Snustad, Ingrid; Størset, Sigmund Østtveit; Ertesvåg, Ivar Ståle

    2015-01-01

    A new setup for the measurement of vapor-liquid phase equilibria of CO2-rich mixtures relevant for carbon capture and storage (CCS) transport conditions is presented. An isothermal analytical method with a variable volume cell is used. The apparatus is capable of highly accurate measurements in terms of pressure, temperature and composition, also in the critical region. Vapor-liquid equilibrium (VLE) measurements for the binary system CO2+N2 are reported at 223, 270, 298 and 303 K, with estim...

  4. 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 (carbon dioxide removal.

  5. Net carbon storage in a popular plantation (POPFACE) after three years of free-air CO2 enrichment

    NARCIS (Netherlands)

    Gielen, B.; Calfapietra, C.; Lukac, M.; Wittig, V.E.; Angelis, de P.; Janssens, I.A.; Moscatelli, M.C.; Grego, S.; Cotrufo, M.F.; Godbold, D.; Hoosbeek, M.R.; Long, S.; Miglietta, F.; Polle, A.; Bernacchi, C.; Davey, P.A.; Ceulemans, R.; Scarascia-Mugnozza, G.

    2005-01-01

    A high-density plantation of three genotypes of Populus was exposed to an elevated concentration of carbon dioxide ([CO2]; 550 µmol mol¿1) from planting through canopy closure using a free-air CO2 enrichment (FACE) technique. The FACE treatment stimulated gross primary productivity by 22 and 11% in

  6. Carbon dioxide capture and geological storage

    OpenAIRE

    2013-01-01

    Sustainable Carbon dioxide Capture and Storage, or CCS, can be achieved using geological means, an approach that differs in many ways from CO2 capture and storage in vegetation. Firstly, it differs because this latter approach enables CO2 to be stored only temporarily – for less than one year in annual plants or for several centuries in tree phytomass. Secondly, CO2 capture is associated with bioconversion of the sun’s energy which is then stored in biochemical form in the phytomass. As the t...

  7. Abiotic CO2 reduction during geologic carbon sequestration facilitated by Fe(II)-bearing minerals

    Science.gov (United States)

    Nielsen, L. C.; Maher, K.; Bird, D. K.; Brown, G. E.; Thomas, B.; Johnson, N. C.; Rosenbauer, R. J.

    2012-12-01

    Redox reactions involving subsurface minerals and fluids and can lead to the abiotic generation of hydrocarbons from CO2 under certain conditions. Depleted oil reservoirs and saline aquifers targeted for geologic carbon sequestration (GCS) can contain significant quantities of minerals such as ferrous chlorite, which could facilitate the abiotic reduction of carbon dioxide to n-carboxylic acids, hydrocarbons, and amorphous carbon (C0). If such reactions occur, the injection of supercritical CO2 (scCO2) could significantly alter the oxidation state of the reservoir and cause extensive reorganization of the stable mineral assemblage via dissolution and reprecipitation reactions. Naturally occurring iron oxide minerals such as magnetite are known to catalyze CO2 reduction, resulting in the synthesis of organic compounds. Magnetite is thermodynamically stable in Fe(II) chlorite-bearing mineral assemblages typical of some reservoir formations. Thermodynamic calculations demonstrate that GCS reservoirs buffered by the chlorite-kaolinite-carbonate(siderite/magnesite)-quartz assemblage favor the reduction of CO2 to n-carboxylic acids, hydrocarbons, and C0, although the extent of abiotic CO2 reduction may be kinetically limited. To investigate the rates of abiotic CO2 reduction in the presence of magnetite, we performed batch abiotic CO2 reduction experiments using a Dickson-type rocking hydrothermal apparatus at temperatures (373 K) and pressures (100 bar) within the range of conditions relevant to GCS. Blank experiments containing CO2 and H2 were used to rule out the possibility of catalytic activity of the experimental apparatus. Reaction of brine-suspended magnetite nanoparticles with scCO2 at H2 partial pressures typical of reservoir rocks - up to 100 and 0.1 bars respectively - was used to investigate the kinetics of magnetite-catalyzed abiotic CO2 reduction. Later experiments introducing ferrous chlorite (ripidolite) were carried out to determine the potential for

  8. 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.

  9. Contribution of increasing CO2 and climate to carbon storage by ecosystems in the United States

    Science.gov (United States)

    Schimel, D.; Melillo, J.; Tian, H.; McGuire, A.D.; Kicklighter, D.; Kittel, T.; Rosenbloom, N.; Running, S.; Thornton, P.; Ojima, D.; Parton, W.; Kelly, R.; Sykes, M.; Neilson, R.; Rizzo, B.

    2000-01-01

    The effects of increasing carbon dioxide (CO2) and climate on net carbon storage in terrestrial ecosystems of the conterminous United States for the period 1895-1993 were modeled with new, detailed historical climate information. For the period 1980-1993, results from an ensemble of three models agree within 25%, simulating a land carbon sink from CO2 and climate effects of 0.08 gigaton of carbon per year. The best estimates of the total sink from inventory data are about three times larger, suggesting that processes such as regrowth on abandoned agricultural land or in forests harvested before 1980 have effects as large as or larger than the direct effects of CO2 and climate. The modeled sink varies by about 100% from year to year as a result of climate variability.

  10. Development of Hollow Fiber Carbon Membranes for CO2 Separation

    OpenAIRE

    He, Xuezhong

    2011-01-01

    CO2 capture from flue gases by membrane technology in post combustion power plants could be used for the reducing of CO2 emissions. Previous work has demonstrated that the carbon membrane can achieve a high separation performance with respect to high CO2 permeability and selectivity over the other gases, such as N2 and O2. The focus of the current work was to find a low-cost precursor and develop a simple process for the preparation of high performance hollow fiber carbon membranes (HFCMs) fo...

  11. Deposition of carbon dioxide

    International Nuclear Information System (INIS)

    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

  12. 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...

  13. Miniature Carbon Dioxide Sensor for Small Unmanned Aircraft Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Phase 1 has seen the development of a revolutionary new type of sensor for making carbon dioxide (CO2) measurements from small Unmanned Aircraft Systems (UAS) and...

  14. Global carbon dioxide emissions from inland waters

    Science.gov (United States)

    Raymond, Peter A.; Hartmann, Jens; Lauerwald, Ronny; Sobek, Sebastian; McDonald, Cory P.; Hoover, Mark; Butman, David; Striegl, Rob; Mayorga, Emilio; Humborg, Christoph; Kortelainen, Pirkko; Durr, Hans H.; Meybeck, Michel; Ciais, Philippe; Guth, Peter

    2013-01-01

    Carbon dioxide (CO2) transfer from inland waters to the atmosphere, known as CO2 evasion, is a component of the global carbon cycle. Global estimates of CO2 evasion have been hampered, however, by the lack of a framework for estimating the inland water surface area and gas transfer velocity and by the absence of a global CO2 database. Here we report regional variations in global inland water surface area, dissolved CO2 and gas transfer velocity. We obtain global CO2 evasion rates of 1.8   petagrams of carbon (Pg C) per year from streams and rivers and 0.32  Pg C yr−1 from lakes and reservoirs, where the upper and lower limits are respectively the 5th and 95th confidence interval percentiles. The resulting global evasion rate of 2.1 Pg C yr−1 is higher than previous estimates owing to a larger stream and river evasion rate. Our analysis predicts global hotspots in stream and river evasion, with about 70 per cent of the flux occurring over just 20 per cent of the land surface. The source of inland water CO2 is still not known with certainty and new studies are needed to research the mechanisms controlling CO2 evasion globally.

  15. Carbon Dioxide Angiography: Scientific Principles and Practice.

    Science.gov (United States)

    Cho, Kyung Jae

    2015-09-01

    Carbon dioxide (CO2) is a colorless, odorless gas which occurs naturally in the atmosphere and human body. With the advent of digital subtraction angiography, the gas has been used as a safe and useful alternative contrast agent in both arteriography and venography. Because of its lack of renal toxicity and allergic potential, CO2 is a preferred contrast agent in patients with renal failure or contrast allergy, and particularly in patients who require large volumes of contrast medium for complex endovascular procedures. Understanding of the unique physical properties of CO2 (high solubility, low viscosity, buoyancy, and compressibility) is essential in obtaining a successful CO2 angiogram and in guiding endovascular intervention. Unlike iodinated contrast material, CO2 displaces the blood and produces a negative contrast for digital subtraction imaging. Indications for use of CO2 as a contrast agent include: aortography and runoff, detection of bleeding, renal transplant arteriography, portal vein visualization with wedged hepatic venous injection, venography, arterial and venous interventions, and endovascular aneurysm repair. CO2 should not be used in the thoracic aorta, the coronary artery, and cerebral circulation. Exploitation of CO2 properties, avoidance of air contamination and facile catheterization technique are important to the safe and effective performance of CO2 angiography and CO2-guided endovascular intervention. PMID:26509137

  16. Response of Heterogeneous and Fractured Carbonate Samples to CO2-Brine Exposure

    Science.gov (United States)

    Smith, M. M.; Mason, H. E.; Hao, Y.; Carroll, S.

    2014-12-01

    Carbonate rock units are often considered as candidate sites for storage of carbon dioxide (CO2), whether as stand-alone reservoirs or coupled with enhanced oil recovery efforts. In order to accept injected carbon dioxide, carbonate reservoirs must either possess sufficient preexisting connected void space, or react with CO2-acidified fluids to produce more pore space and improve permeability. However, upward migration of CO2 through barrier zones or seal layers must be minimized for effective safe storage. Therefore, prediction of the changes to porosity and permeability in these systems over time is a key component of reservoir management. Towards this goal, we present the results of several experiments on carbonate core samples from the Wellington, Kansas 1-32 well, conducted under reservoir temperature, pressure, and CO2 conditions. These samples were imaged by X-ray computed tomography (XRCT) and analyzed with nuclear magnetic resonance (NMR) spectroscopy both prior to and after reaction with CO2-enriched brines. The carbonate samples each displayed distinct responses to CO2 exposure in terms of permeability change with time and relative abundance of calcite versus dolomite dissolution. The measured permeability of each sample was also much lower than that estimated by downhole NMR logging, with samples with larger fractured regions possessing higher permeability values. We present also our modeling approach and preliminary simulation results for a specific sample from the targeted injection zone. The heterogeneous composition as well as the presence of large fractured zones within the rock necessitated the use of a nested three-region approach to represent the range of void space observed via tomography. Currently, the physical response to CO2-brine flow (i.e., pressure declines with time) is reproduced well but the extent of chemical reaction is overestimated by the model.

  17. Cost evaluation of CO2 sequestration by aqueous mineral carbonation

    International Nuclear Information System (INIS)

    A cost evaluation of CO2 sequestration by aqueous mineral carbonation has been made using either wollastonite (CaSiO3) or steel slag as feedstock. First, the process was simulated to determine the properties of the streams as well as the power and heat consumption of the process equipment. Second, a basic design was made for the major process equipment, and total investment costs were estimated with the help of the publicly available literature and a factorial cost estimation method. Finally, the sequestration costs were determined on the basis of the depreciation of investments and variable and fixed operating costs. Estimated costs are 102 and 77 euro/ton CO2 net avoided for wollastonite and steel slag, respectively. For wollastonite, the major costs are associated with the feedstock and the electricity consumption for grinding and compression (54 and 26 euro/ton CO2 avoided, respectively). A sensitivity analysis showed that additional influential parameters in the sequestration costs include the liquid-to-solid ratio in the carbonation reactor and the possible value of the carbonated product. The sequestration costs for steel slag are significantly lower due to the absence of costs for the feedstock. Although various options for potential cost reduction have been identified, CO2 sequestration by current aqueous carbonation processes seems expensive relative to other CO2 storage technologies. The permanent and inherently safe sequestration of CO2 by mineral carbonation may justify higher costs, but further cost reductions are required, particularly in view of (current) prices of CO2 emission rights. Niche applications of mineral carbonation with a solid residue such as steel slag as feedstock and/or a useful carbonated product hold the best prospects for an economically feasible CO2 sequestration process

  18. Accelerated Carbonation of Steel Slags Using CO2 Diluted Sources: CO2 Uptakes and Energy Requirements

    OpenAIRE

    Baciocchi, Renato; Costa, Giulia; Polettini, Alessandra; Pomi, Raffaella; Stramazzo, Alessio; Zingaretti, Daniela

    2016-01-01

    This work presents the results of carbonation experiments performed on Basic Oxygen Furnace (BOF) steel slag samples employing gas mixtures containing 40 and 10% CO2 vol. simulating the gaseous effluents of gasification and combustion processes respectively, as well as 100% CO2 for comparison purposes. Two routes were tested, the slurry-phase (L/S = 5 l/kg, T = 100°C and Ptot = 10 bar) and the thin-film (L/S = 0.3–0.4 l kg, T = 50°C and Ptot = 7–10 bar) routes. For each one, the CO2 uptake ac...

  19. Removal of CO2 in a multistage fluidized bed reactor by diethanol amine impregnated activated carbon.

    Science.gov (United States)

    Das, Dipa; Samal, Debi Prasad; Meikap, Bhim C

    2016-07-28

    To mitigate the emission of carbon dioxide (CO2), we have developed and designed a four-stage fluidized bed reactor. There is a counter current exchange between solid adsorbent and gas flow. In this present investigation diethanol amine (DEA) impregnated activated carbon made from green coconut shell was used as adsorbent. This type of adsorbent not only adsorbs CO2 due to the presence of pore but also chemically reacts with CO2 and form secondary zwitterions. Sampling and analysis of CO2 was performed using Orsat apparatus. The effect of initial CO2 concentration, gas velocity, solid rate, weir height etc. on removal efficiency of CO2 have been investigated and presented. The percentage removal of CO2 has been found close to 80% under low gas flow rate (0.188 m/s), high solid flow rate (4.12 kg/h) and weir height of 50 mm. From this result it has been found out that multistage fluidized bed reactor may be a suitable equipment for removal of CO2 from flue gas. PMID:27163861

  20. The Fluid Mechanics of Carbon Dioxide Sequestration

    Science.gov (United States)

    Huppert, Herbert E.; Neufeld, Jerome A.

    2014-01-01

    Humans are faced with a potentially disastrous global problem owing to the current emission of 32 gigatonnes of carbon dioxide (CO2) annually into the atmosphere. A possible way to mitigate the effects is to store CO2 in large porous reservoirs within the Earth. Fluid mechanics plays a key role in determining both the feasibility and risks involved in this geological sequestration. We review current research efforts looking at the propagation of CO2 within the subsurface, the possible rates of leakage, the mechanisms that act to stably trap CO2, and the geomechanical response of the crust to large-scale CO2 injection. We conclude with an outline for future research.

  1. Supercritical carbon dioxide: a solvent like no other

    OpenAIRE

    Jocelyn Peach; Julian Eastoe

    2014-01-01

    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 at...

  2. Carbon dioxide kinetics and capnography during critical care

    OpenAIRE

    Anderson, Cynthia T; Breen, Peter H

    2000-01-01

    Greater understanding of the pathophysiology of carbon dioxide kinetics during steady and nonsteady state should improve, we believe, clinical care during intensive care treatment. Capnography and the measurement of end-tidal partial pressure of carbon dioxide (PETCO2) will gradually be augmented by relatively new measurement methodology, including the volume of carbon dioxide exhaled per breath (VCO2,br) and average alveolar expired PCO2 (PA̅E̅CO2). Future directions include the study of oxy...

  3. Reduction of CO2 emissions by mineral carbonation : steelmaking slags as rawmaterial with a pure calcium carbonate end product

    OpenAIRE

    Eloneva, Sanni

    2010-01-01

    Mineral carbonation is one of the options that can contribute to the reduction of carbon dioxide emissions for climate change mitigation purposes. Steel manufacturing, which is one of the biggest industrial sources of CO2 emissions, could benefit from this option by utilizing its own by-products, i.e., steelmaking slags, to combine with CO2. Additional benefits would be achieved if the end product was a pure and marketable calcium carbonate. The utilization of CaCO3 derived from steelmaking s...

  4. 开放式空气CO2浓度升高对冬小麦生长和N吸收的影响%Effects of Free-air Carbon Dioxide Enrichment on Growth and Uptake of Nitrogen in Winter Wheat

    Institute of Scientific and Technical Information of China (English)

    马红亮; 朱建国; 谢祖彬; 刘钢; 张雅丽; 曾青

    2005-01-01

    利用FACE(free-air carbon dioxide enrichment)技术平台,设常CO2(ambient CO2)和高CO2(elevated CO2,ambient+200 μmol*mol-1)2个水平和常N(NN,250 kg N·hm-2)和低N(LN,150 kg N·hm-2)2个水平,研究CO2浓度升高对冬小麦(Triticum aestivum L.)整个生长期生物量和氮(N)吸收的影响.结果表明,CO2浓度升高使冬小麦各部分的生物量平均增加28.3%~44.5%,拔节期增幅最大,达36.8%~91.2%,而且NN处理的生物量增幅比LN处理低.CO2浓度升高不同程度地降低了小麦的N含量,但是增加了N的吸收,在拔节期LN和NN处理下分别增加20.8%和29.2%.CO2浓度升高使小麦在拔节期NN处理的N相对吸收速率增加44.1%.说明在大气CO2浓度升高条件下,小麦会通过生物量的增加固定更多的C,增加对N养分的需求,应着重考虑提高小麦拔节期间的施氮肥水平.

  5. Effect of accelerated carbonation on AOD stainless steel slag for its valorisation as a CO2-sequestering construction material

    OpenAIRE

    Salman, Muhammad Salman; Cizer, Özlem; Pontikes, Yiannis; Santos, Rafael; Vandewalle, Lucie; Blanpain, Bart; Van Balen, Koen

    2014-01-01

    Non-stabilized Argon Oxygen Decarburisation (AODNS) slag in powdered form was examined for its carbon dioxide sequestration capacity and for its potential utilization in the fabrication of high value building materials. The curing of the sample was carried out in two accelerated carbonation environments: i) in a carbonation chamber, maintained at atmospheric pressure, 22 °C, 5 vol.% CO2 and 80% RH; and ii) in a carbonation reactor, where the CO2 partial pressure (pCO2) and temperature could b...

  6. Maintaining quality of not from concentrate peach juice by high pressure carbon dioxide treatment%高压CO2处理保持非还原桃汁的品质

    Institute of Scientific and Technical Information of China (English)

    周林燕; 王永涛; 刘凤霞; 毕秀芳; 廖小军

    2013-01-01

    In the juice industry, thermal treatment is the most common and least expensive technology for pasteurization or sterilization. Unfortunately, the method easily leads to degradation of some product qualities as well. HPCD (high pressure carbon dioxide) has been reported as an alternative cold pasteurization technique for foods, since it could effectively inactivate microorganisms and enzymes in liquid food. Some detrimental effects of HPCD on food quality have been reported. But compared to traditional techniques, HPCD avoids drawbacks such as lack of retention of flavor, denaturation of nutrients, of production of side toxic reactions, as well as changes in physical, mechanical, and optical properties of the material involved in the treatment. In this study, the effects of HPCD on NFC (Not from concentrate) peach juice quality were investigated, and temperature, pressure, and time were proposed as the main parameters. The pH value and the total soluble content of untreated NFC peach juice were 3.82 and 10.3°Brix, respectively. HPCD had no effect on the pH values and total soluble contents. This was possibly attributed to a lower pH (3.82) in the original juices. At this pH the carbonic acid formed by CO2 dissolution into juices with difficultly dissociated into free hydrogen ions, because the dissociation constants of carbonic acid and bicarbonate were pKa=6.57 and pKa=10.62, respectively. The L, a, b values of color parameters was decreased while browning degrees were increased in HPCD-treated juice, possibly due to the non-enzyme browning during HPCD. Thereafter, it was found that the polyphenol oxidase was susceptible to HPCD. The main phenolic compounds in the NFC juice were (+)-catechin, chlorogenic acid, neochlorogenic acid, and ferulic acid measured by HPLC, and the results showed that HPCD had no effect on the phenolic compounds. Moreover, the antioxidant capacities of NFC juice after HPCD were enhanced with increasing treatment time measured by FRAP and

  7. An Empirical Research on Measuring Carbon Dioxide Emissions from Urban Tourism:A Case Study of Shenzhen%城市旅游业CO2排放量估算研究——以深圳市为例

    Institute of Scientific and Technical Information of China (English)

    汪清蓉

    2012-01-01

    基于碳排放理论及旅游者的消费结构特征,提出城市旅游业能源消耗及CO2排放测算模型,计算并分析了2008年深圳市旅游业能源消耗及CO2排放.结果表明:各组分排放量从大到小依次是行、食、游、住、购、娱,旅游业产生的温室气体不容忽视;旅游规模、旅游交通工具的选择是影响旅游业CO2排放量的重要因素;在旅游产业日益发展的情况下旅游业面临能源消耗、排放量增加和节能减排的双重压力.最后就能源消耗计算模型的完善、能源参数的研究以及下一步研究方向进行了讨论,并提出了相应的建议.%Measuring carbon dioxide emissions from tourism is the starting point for the realization of industrial energy saving goals and the basis for the formulation of governmental reduction policies. However, it has also become a big problem due to the current situation of tourism in the country and the lack of energy consumption data Case studies on CQz emissions from urban tourism are rare, though city remains the most important space vector for tourism development Based on the theory of carbon dioxide emissions and the consumption structure of tourists, the paper proposes the calculation model of energy consumption and carbon dioxide emissions. Taking Shenzhen City for example, this paper calculates and analyses energy consumption and carbon dioxide emissions from Shenzhen s urban tourism in 2008. The result shows that; l)the descending order of carbon dioxide emissions of tourism s component is transportation,food, tour,housing,shopping, entertainment, which indicates that GHG emission from urban tourism cannot be ignored; 2) travel size and travel transport choices are two key factors affecting energy consumption and CO2 emissions from urban, tourism; 3)though growing fast,urban tourism is facing dual pressure from energy consumption, increase in emissions and mitigation. The paper also makes suggestions on the improvement of

  8. Kinetics of CO2 exchange with carbonic anhydrase immobilized on fiber membranes in artificial lungs.

    Science.gov (United States)

    Arazawa, D T; Kimmel, J D; Federspiel, W J

    2015-06-01

    Artificial lung devices comprised of hollow fiber membranes (HFMs) coated with the enzyme carbonic anhydrase (CA), accelerate removal of carbon dioxide (CO2) from blood for the treatment of acute respiratory failure. While previous work demonstrated CA coatings increase HFM CO2 removal by 115 % in phosphate buffered saline (PBS), testing in blood revealed a 36 % increase compared to unmodified HFMs. In this work, we sought to characterize the CO2 mass transport processes within these biocatalytic devices which impede CA coating efficacy and develop approaches towards improving bioactive HFM efficiency. Aminated HFMs were sequentially reacted with glutaraldehyde (GA), chitosan, GA and afterwards incubated with a CA solution, covalently linking CA to the surface. Bioactive CA-HFMs were potted in model gas exchange devices (0.0119 m(2)) and tested for esterase activity and CO2 removal under various flow rates with PBS, whole blood, and solutions containing individual blood components (plasma albumin, red blood cells or free carbonic anhydrase). Results demonstrated that increasing the immobilized enzyme activity did not significantly impact CO2 removal rate, as the diffusional resistance from the liquid boundary layer is the primary impediment to CO2 transport by both unmodified and bioactive HFMs under clinically relevant conditions. Furthermore, endogenous CA within red blood cells competes with HFM immobilized CA to increase CO2 removal. Based on our findings, we propose a bicarbonate/CO2 disequilibrium hypothesis to describe performance of CA-modified devices in both buffer and blood. Improvement in CO2 removal rates using CA-modified devices in blood may be realized by maximizing bicarbonate/CO2 disequilibrium at the fiber surface via strategies such as blood acidification and active mixing within the device. PMID:26032115

  9. 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 with...

  10. Development of a Method for Measuring Carbon Balance in Chemical Sequestration of CO2

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Zhongxian; Pan, Wei-Ping; Riley, John T.

    2006-09-09

    Anthropogenic CO2 released from fossil fuel combustion is a primary greenhouse gas which contributes to “global warming.” It is estimated that stationary power generation contributes over one-third of total CO2 emissions. Reducing CO2 in the atmosphere can be accomplished either by decreasing the rate at which CO2 is emitted into the atmosphere or by increasing the rate at which it is removed from it. Extensive research has been conducted on determining a fast and inexpensive method to sequester carbon dioxide. These methods can be classified into two categories, CO2 fixation by natural sink process for CO2, or direct CO2 sequestration by artificial processes. In direct sequestration, CO2 produced from sources such as coal-fired power plants, would be captured from the exhausted gases. CO2 from a combustion exhaust gas is absorbed with an aqueous ammonia solution through scrubbing. The captured CO2 is then used to synthesize ammonium bicarbonate (ABC or NH4HCO3), an economical source of nitrogen fertilizer. In this work, we studied the carbon distribution after fertilizer is synthesized from CO2. The synthesized fertilizer in laboratory is used as a “CO2 carrier” to “transport” CO2 from the atmosphere to crops. After biological assimilation and metabolism in crops treated with ABC, a considerable amount of the carbon source is absorbed by the plants with increased biomass production. The majority of the unused carbon source percolates into the soil as carbonates, such as calcium carbonate (CaCO3) and magnesium carbonate (MgCO3). These carbonates are environmentally benign. As insoluble salts, they are found in normal rocks and can be stored safely and permanently in soil. This investigation mainly focuses on the carbon distribution after the synthesized fertilizer is applied to soil. Quantitative examination of carbon distribution in an ecosystem is a challenging task since the carbon in the soil may come from various sources. Therefore synthesized 14C

  11. Carbon dioxide accounting:2014 Commonwealth Games Atheletes’ Village

    OpenAIRE

    Sampson, Jennifer; Biesta, Mark; Crapper, Martin; Hall, Iain; Shepherd, Alan

    2013-01-01

    A spreadsheet-based tool for whole-life carbon dioxide accounting of soil remediation projects has been created. The tool carries out whole-life analysis of projects, including supply chain emissions. It was applied to the Glasgow 2014 Commonwealth Games Athletes' Village remediation project, for which a calculated total ‘carbon footprint’ of 2328 t of carbon dioxide equivalent emission (tCO2e) was obtained. This is 71 tCO2e/ha of the site or 13·3 kgCO2e/t whole life of soil treated. These fi...

  12. DUSEL CO2: A deep underground laboratory for geologic carbon sequestration studies

    Science.gov (United States)

    Peters, C. A.; Dobson, P. F.; Oldenburg, C. M.; Scherer, G.; Onstott, T. C.; Birkholzer, J. T.; Freifeld, B. M.; Celia, M. A.; Wang, J. S.; Prevost, J.

    2009-12-01

    The objective of geologic sequestration of carbon dioxide as a greenhouse gas mitigation strategy is the long-term containment of CO2 in deep underground formations. To develop a sound understanding of geologic carbon sequestration, we will build a deep underground laboratory to study the processes of storing and trapping CO2, including the risks of unintended leakage. The laboratory will be part of the new DUSEL facility at the Homestake mine in South Dakota. In this presentation, we will highlight the features and capabilities of the planned facility, to be called “DUSEL CO2”. The experimental design exploits the nearly half-kilometer vertical extent of existing “sandline” borings at Homestake. Pipes will be installed within the sandlines to serve as long flow columns. These columns will contain the CO2 and allow experimentation at the same pressure and temperature conditions as in deep subsurface reservoirs. Fill materials will mimic sedimentary layering, as well as cements in plugged wells. Instrumentation will enable detailed monitoring of flow, pressure, temperature, brine composition, geomechanics, and microbial activity. As part of the initial suite of experiments, we plan to simulate a leak in which CO2 changes from a supercritical fluid to a subcritical gas as the pressure drops during upflow over tens to hundreds of meters. We will test for possible acceleration in CO2 flow due to increasing buoyancy. Also, we will examine the interactions of CO2 with caprocks and well cements, and determine whether CO2 will enlarge flow pathways or cause self-sealing. Finally, we will investigate the effects of anaerobic, thermophilic bacteria on CO2 conversion to methane and carbonate. The findings from these unique experiments will advance carbon management technology worldwide and help reduce global greenhouse gas emissions.

  13. 超临界CO2萃取穿心莲内酯的实验研究%Supercritical Carbon Dioxide Extraction of Andrographolide from Andrographis paniculata: Effect of the Solvent Flow Rate,Pressure,and Temperature

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Andrographis paniculata Nees has been extensively used for traditional medicine and help against fever,dysentery,diarrhoea,inflammation,and sore throat. In this study,andrographolide,the main component of this plant was extracted from the leaves of A. paniculata using supercritical carbon dioxide. The operating pressures were varied from 7.50 to 20 MPa,the temperatures were varied from 30℃ to 60℃,and the flow rates were varied 3g sample of A. paniculata ground-dried leaves. The measured extraction rate was found to be about 0.0174g of andrographolide per gram of andrographolide present in the leaves per hour of operation. The future studies must focus on the interaction between the various operating parameters such as temperature,pressure,and flow rate of supercritical carbon dioxide.

  14. 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.

  15. Natural CO2 Analogs for Carbon Sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Scott H. Stevens; B. Scott Tye

    2005-07-31

    The report summarizes research conducted at three naturally occurring geologic CO{sub 2} fields in the US. The fields are natural analogs useful for the design of engineered long-term storage of anthropogenic CO{sub 2} in geologic formations. Geologic, engineering, and operational databases were developed for McElmo Dome in Colorado; St. Johns Dome in Arizona and New Mexico; and Jackson Dome in Mississippi. The three study sites stored a total of 2.4 billion t (46 Tcf) of CO{sub 2} equivalent to 1.5 years of power plant emissions in the US and comparable in size with the largest proposed sequestration projects. The three CO{sub 2} fields offer a scientifically useful range of contrasting geologic settings (carbonate vs. sandstone reservoir; supercritical vs. free gas state; normally pressured vs. overpressured), as well as different stages of commercial development (mostly undeveloped to mature). The current study relied mainly on existing data provided by the CO{sub 2} field operator partners, augmented with new geochemical data. Additional study at these unique natural CO{sub 2} accumulations could further help guide the development of safe and cost-effective design and operation methods for engineered CO{sub 2} storage sites.

  16. Mineral sequestration of CO2 by aqueous carbonation of coal combustion fly-ash

    International Nuclear Information System (INIS)

    The increasing CO2 concentration in the Earth's atmosphere, mainly caused by fossil fuel combustion, has led to concerns about global warming. A technology that could possibly contribute to reducing carbon dioxide emissions is the in-situ mineral sequestration (long term geological storage) or the ex-situ mineral sequestration (controlled industrial reactors) of CO2. In the present study, we propose to use coal combustion fly-ash, an industrial waste that contains about 4.1 wt.% of lime (CaO), to sequester carbon dioxide by aqueous carbonation. The carbonation reaction was carried out in two successive chemical reactions, first, the irreversible hydration of lime. CaO + H2O → Ca(OH)2 second, the spontaneous carbonation of calcium hydroxide suspension. Ca(OH)2 + CO2 → CaCO3 + H2O A significant CaO-CaCO3 chemical transformation (approximately 82% of carbonation efficiency) was estimated by pressure-mass balance after 2 h of reaction at 30 deg. C. In addition, the qualitative comparison of X-ray diffraction spectra for reactants and products revealed a complete CaO-CaCO3 conversion. The carbonation efficiency of CaO was independent on the initial pressure of CO2 (10, 20, 30 and 40 bar) and it was not significantly affected by reaction temperature (room temperature '20-25', 30 and 60 deg. C) and by fly-ash dose (50, 100, 150 g). The kinetic data demonstrated that the initial rate of CO2 transfer was enhanced by carbonation process for our experiments. The precipitate calcium carbonate was characterized by isolated micrometric particles and micrometric agglomerates of calcite (SEM observations). Finally, the geochemical modelling using PHREEQC software indicated that the final solutions (i.e. after reaction) are supersaturated with respect to calcium carbonate (0.7 ≤ saturation index ≤ 1.1). This experimental study demonstrates that 1 ton of fly-ash could sequester up to 26 kg of CO2, i.e. 38.18 ton of fly-ash per ton of CO2 sequestered. This confirms the

  17. Capillary Trapping of CO2 in Oil Reservoirs: Observations in a Mixed-Wet Carbonate Rock.

    Science.gov (United States)

    Al-Menhali, Ali S; Krevor, Samuel

    2016-03-01

    Early deployment of carbon dioxide storage is likely to focus on injection into mature oil reservoirs, most of which occur in carbonate rock units. Observations and modeling have shown how capillary trapping leads to the immobilization of CO2 in saline aquifers, enhancing the security and capacity of storage. There are, however, no observations of trapping in rocks with a mixed-wet-state characteristic of hydrocarbon-bearing carbonate reservoirs. Here, we found that residual trapping of supercritical CO2 in a limestone altered to a mixed-wet state with oil was significantly less than trapping in the unaltered rock. In unaltered samples, the trapping of CO2 and N2 were indistinguishable, with a maximum residual saturation of 24%. After the alteration of the wetting state, the trapping of N2 was reduced, with a maximum residual saturation of 19%. The trapping of CO2 was reduced even further, with a maximum residual saturation of 15%. Best-fit Land-model constants shifted from C = 1.73 in the water-wet rock to C = 2.82 for N2 and C = 4.11 for the CO2 in the mixed-wet rock. The results indicate that plume migration will be less constrained by capillary trapping for CO2 storage projects using oil fields compared with those for saline aquifers. PMID:26812184

  18. 长三角地区旅游业能源消耗的CO_2排放测度研究%Measuring carbon dioxide emissions from energy consumption by tourism in Yangtze River Delta

    Institute of Scientific and Technical Information of China (English)

    谢园方; 赵媛

    2012-01-01

    旅游业与气候环境变化息息相关,低碳旅游是旅游业对气候变化的积极响应,也是低碳经济的延伸,将会给全球旅游业带来深远影响。但目前国内大部分有关低碳旅游的研究仍停留在定性阶段,尤其是旅游业碳排放的测度研究仍比较薄弱。本文在深入分析和总结国内外已有研究的基础上,以能源消耗平衡表为依据,借鉴"旅游消费剥离系数"概念,构建出符合我国目前统计口径的旅游业碳排放测度方法。并以长江三角洲地区为研究范围,对江苏、浙江和上海三地旅游业碳排放进行测度和对比分析。研究表明:目前在长三角地区,旅游业碳排放总量持续攀升,并与旅游业总收入成正相关。其中旅游交通仓储和邮电业碳排放在旅游业碳排放总量中占主导地位,而旅游餐饮、住宿和购物过程中的碳排放也不容忽视。旅游收入增长与旅游低碳化发展的矛盾仍然十分突出,迫切需要转变旅游业发展方式。%Climate change is projected to have great impact on tourism in various ways;however,tourism also contributes to climate change through the carbon dioxide emissions from transport,accommodation and other tourist activities.Now low-carbon tourism is becoming a popular choice to protect the environment for tourists.A lot of people have already accepted the low-carbon conception,and more and more people like it.But there are still numerous hurdles on the road to really achieve the low-carbon goal in our travels,because there is a large amount of direct energy consumption in the form of fossil fuels or indirect energy consumption in the form of electricity during the whole journey.And this consumption directly leads to more emissions of carbon dioxide.According to international experience,measuring carbon dioxide emissions from tourism is a key step to developing low-carbon tourism.However,the study of low-carbon tourism in China is still in its

  19. Killing wild geese with carbon dioxide or a mixture of carbon dioxide and argon

    NARCIS (Netherlands)

    Gerritzen, M.A.; Reimert, H.G.M.; Lourens, A.; Bracke, M.B.M.; Verhoeven, M.T.W.

    2013-01-01

    The killing of animals is the subject of societal and political debate. Wild geese are caught and killed on a regular basis for fauna conservation and damage control. Killing geese with carbon dioxide (CO2) is commonly practiced, but not listed in legislation on the protection of flora and fauna, an

  20. Urban carbon dioxide in Portland, Oregon

    Science.gov (United States)

    Bostrom, G. A.; Brooks, M.; Rice, A. L.

    2010-12-01

    Ambient concentrations of atmospheric carbon dioxide (CO2) are reported for the Portland, Oregon (USA) metropolitan region since late July, 2009. Three stationary locations were established: a downtown location on the campus of Portland State University; a residential site in southeast Portland; and a rural station on Sauvie Island, located ~30km northwest of Portland in the Columbia River Gorge. Continuous measurements of CO2 at the sites average 400-410ppm and show considerable variability due to CO2 sources, sinks and meteorological drivers of ventilation. Within this variability, a marked 20-30ppm diurnal cycle is observed due to photosynthetic activity and variations in the planetary boundary layer. In-city CO2 concentrations are on average enhanced by 5-6ppm over the Sauvie Island site during upgorge wind conditions, a difference which is greatest in the afternoon. Measurements of the 13C/12C ratio of CO2 in downtown Portland are significantly depleted in 13C relative to 12C compared with background air and suggest that regional CO2 is dominated by petroleum sources (70-80%). High degrees of relationship between CO2 variability and primary air pollutants CO and NO (r2=0.70 to 0.80), measured by the Oregon Department of Environmental Quality at the Southeast Portland location, corroborate this finding and illustrate the importance of traffic emissions on elevated ambient CO2 concentrations. In addition to CO2 at the fixed sites, measurements of street-level CO2 concentrations were obtained using a mobile instrument mounted in a bike trailer. Results from these field data show relatively homogenous CO2 concentrations throughout residential Portland neighborhoods with significant enhancements in CO2 on busy roadways or near areas of traffic congestion.

  1. Surface chemistry of polymers. The adsorption of carbon dioxide and sulfur dioxide on polyvinylidene chloride

    OpenAIRE

    Stoeckli, Fritz

    2007-01-01

    Isotherms for the adsorption of nitrogen (77 K), carbon dioxide (195-247 K) and sulfur dioxide (254-293 K) on polyvinylidene chloride have been measured volumetrically. The B.E.T. cross-sectional areas of 18 Å2 (CO2) and 24 Å2 (SO2) are comparable to liquid density values. The isosteric heat of adsorption of CO2 is constant for 0.2

  2. 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.

  3. Electrochemical carbon dioxide reduction on rough copper surfaces

    NARCIS (Netherlands)

    Kas, R.

    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 renewa

  4. Synthesis and characterization of zwitterionic carbon dioxide fixing reagents

    DEFF Research Database (Denmark)

    Mikkelsen, Mette; Jørgensen, Mikkel; Krebs, Frederik C

    2010-01-01

    The synthesis of three amine-based carbon dioxide fixing reagents is presented. The reagents were designed so that they would be able to bind CO2 reversibly through the formation of the well known carbamates that was stabilized through forming a zwitterion. CO2 fixing experiments were performed...

  5. Miniaturized remission sensor for carbon dioxide detection

    International Nuclear Information System (INIS)

    Recently, optical sensors for detection of carbon dioxide (CO2) 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 CO2 detection. The principle of CO2 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 CO2 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.

  6. Carbon dioxide and the radiation budget

    International Nuclear Information System (INIS)

    This chapter addresses the radiative forcing of the Earth-atmosphere system caused by an increase in carbon dioxide (CO2) levels that can lead to climate change. The importance of the Earth's radiation budget is described, and the radiative properties of CO2 and other radiatively important gases are presented. Methods of computing gaseous absorption and their accuracy are discussed. Components of the radiation budget (solar and longwave) are described along with the effect of variations in CO2 concentration. Because aerosols and clouds also have important radiative properties, the effects of changes in aerosol and cloud amounts are also discussed. The purpose of this chapter is to provide an overview of the radiative effects of CO2 and other atmospheric constituents that are important in determining the potential climatic effects of changes in atmospheric composition

  7. Histidine-catalyzed synthesis of cyclic carbonates in supercritical carbon dioxide

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The coupling reaction of carbon dioxide with epoxides was investigated using naturally occurring α-amino acids as the catalyst in supercritical carbon dioxide and it was found that L-histidine is the most active catalyst.In the presence of 0.8 mol% of L-histidine at 130°C under 8 MPa of CO2,the reaction of carbon dioxide with epoxides proceeded smoothly,affording corresponding cyclic carbonates in good to excellent yields.

  8. Carbon dioxide emissions from biochar in soil

    DEFF Research Database (Denmark)

    Bruun, S; Clauson-Kaas, S; Bobul'ská, L;

    2014-01-01

    -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...... evolution. Finally, we found that both production temperature and clay content affect biochar mineralization. As protective mechanisms hypothesized to prevent degradation of organic matter in soil usually implicate clay, we conclude that biochar is likely to be protected from mineralization during the early......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...

  9. CO2 sensing at room temperature using carbon nanotubes coated core fiber Bragg grating

    Science.gov (United States)

    Shivananju, B. N.; Yamdagni, S.; Fazuldeen, R.; Sarin Kumar, A. K.; Hegde, G. M.; Varma, M. M.; Asokan, S.

    2013-06-01

    The sensing of carbon dioxide (CO2) at room temperature, which has potential applications in environmental monitoring, healthcare, mining, biotechnology, food industry, etc., is a challenge for the scientific community due to the relative inertness of CO2. Here, we propose a novel gas sensor based on clad-etched Fiber Bragg Grating (FBG) with polyallylamine-amino-carbon nanotube coated on the surface of the core for detecting the concentrations of CO2 gas at room temperature, in ppm levels over a wide range (1000 ppm-4000 ppm). The limit of detection observed in polyallylamine-amino-carbon nanotube coated core-FBG has been found to be about 75 ppm. In this approach, when CO2 gas molecules interact with the polyallylamine-amino-carbon nanotube coated FBG, the effective refractive index of the fiber core changes, resulting in a shift in Bragg wavelength. The experimental data show a linear response of Bragg wavelength shift for increase in concentration of CO2 gas. Besides being reproducible and repeatable, the technique is fast, compact, and highly sensitive.

  10. Supercritical CO2-driven,periodic patterning on one-dimensionals carbon nanomaterials

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    One-dimensional carbon nano-materials,in particular carbon nanotubes (CNTs) and carbon nanofibers (CNFs),are of scientific and technological interest due to their satisfactory properties and ability to serve as templates for directed assembly.In this work,linear high density polyethylene (PE) was periodically decorated on CNTs and CNFs using a supercritical carbon dioxide (scCO2)antisolvent-induced polymer epitaxy (SAIPE) method,leading to nano-hybrid shish-kebab (NHSK) structures.The formation mechanism of different morphologies of PE lamellae on CNTs and CNFs has been discussed.Palladium nanoparticles were synthesized and immobilized on the PE/CNF NHSK structure with the assistance of scCO2.The obtained hierarchical nano-hybrid architecture may find applications in microfabrication and other related fields.

  11. Mechanisms of aqueous wollastonite carbonation as a possible CO2 sequestration process

    International Nuclear Information System (INIS)

    The mechanisms of aqueous wollastonite carbonation as a possible carbon dioxide sequestration process were investigated experimentally by systematic variation of the reaction temperature, CO2 pressure, particle size, reaction time, liquid to solid ratio and agitation power. The carbonation reaction was observed to occur via the aqueous phase in two steps: (1) Ca leaching from the CaSiO3 matrix and (2) CaCO3 nucleation and growth. Leaching is hindered by a Ca-depleted silicate rim resulting from incongruent Ca-dissolution. Two temperature regimes were identified in the overall carbonation process. At temperatures below an optimum reaction temperature, the overall reaction rate is probably limited by the leaching rate of Ca. At higher temperatures, nucleation and growth of calcium carbonate is probably limiting the conversion, due to a reduced (bi)carbonate activity. The mechanisms for the aqueous carbonation of wollastonite were shown to be similar to those reported previously for an industrial residue and a Mg-silicate. The carbonation of wollastonite proceeds rapidly relative to Mg-silicates, with a maximum conversion in 15 min of 70% at 200C, 20 bar CO2 partial pressure and a particle size of <38 μm. The obtained insight in the reaction mechanisms enables the energetic and economic assessment of CO2 sequestration by wollastonite carbonation, which forms an essential next step in its further development

  12. Magnesium oxide nanoparticles on green activated carbon as efficient CO2 adsorbent

    International Nuclear Information System (INIS)

    This study was focused on carbon dioxide (CO2) adsorption ability using Magnesium oxide (MgO) nanoparticles and MgO nanoparticles supported activated carbon based bamboo (BAC). The suitability of MgO as a good CO2 adsorbent was clarified using Thermodynamic considerations (Gibbs-Helmholtz relationship). The ΔH and ΔG of this reaction were − 117.5 kJ⋅mol−1 and − 65.4 kJ⋅mol−1, respectively, at standard condition (298 K and 1 atm). The complete characterization of these adsorbent were conducted by using BET, XRD, FTIR, TEM and TPD−CO2. The surface areas for MgO nanoparticles and MgO nanoparticles supported BAC were 297.1 m2/g and 702.5 m2/g, respectively. The MgO nanoparticles supported BAC shown better physical and chemical adsorption ability with 39.8 cm3/g and 6.5 mmol/g, respectively. The combination of MgO nanoparticle and BAC which previously prepared by chemical method can reduce CO2 emissions as well as better CO2 adsorption behavior. Overall, our results indicate that nanoparticles of MgO on BAC posses unique surface chemistry and their high surface reactivity coupled with high surface area allowed them to approach the goal as an efficient CO2 adsorbent

  13. Porous Carbon Based Solid Adsorbents for Carbon Dioxide Capture

    OpenAIRE

    Travis, W.

    2015-01-01

    The aim of this project is the design, synthesis and characterisation of porous carbon structures capable of the selective capture of carbon dioxide (CO2) from the exhaust gases of coal and gas post-combustion power stations. In such systems, the fossil fuel is burnt in an air environment producing CO2 as just one of a multi-component flue gas. This flue gas is expected to contain nitrogen and water among other constituents. It is at ambient pressures and temperatures of ≥323 K. Successful ca...

  14. Carbon dioxide methanation for intensified reactors

    OpenAIRE

    Coronado Martín, Irene

    2015-01-01

    The present work is related to the development of sustainable energy systems based on the Power-to-Gas concept. The main objective is to utilise renewable hydrogen and carbon dioxide to produce methane for storage in the natural gas infrastructure. Multitubular fixed-bed reactors are established at industrial scale for CO2 methanation. Catalytic pellets commonly loaded in this type of reactor involve poor heat transfer and high pressure drop that lead to inefficient processes. Today, reac...

  15. Pulsed discharge plasmas in supercritical carbon dioxide

    OpenAIRE

    Kiyan, Tsuyoshi; Uemura, A.; Tanaka, K.; Zhang, C. H.; Namihira, Takao; Sakugawa, Takashi; Katsuki, Sunao; Akiyama, Hidenori; Roy, B.C; Sasaki, M.; Goto, M; キヤン, ツヨシ; ナミヒラ, タカオ; サクガワ, タカシ; カツキ, スナオ

    2005-01-01

    In recent years, several studies about electrical discharge plasma in supercritical carbon dioxide (CO2) have been carried out. One of the unique characteristics of supercritical fluid is a large density fluctuation near the critical point that can result in marked dramatic changes of thermal conductivity. Therefore, the electrical discharge plasma produced in supercritical fluid has unique features and reactions unlike those of normal plasma produced in gas phase. In our experiments, two typ...

  16. CIVIL AVIATION CARBON DIOXIDE EMISSIONS IN CHINA

    OpenAIRE

    Chen, Sainan

    2013-01-01

    With the social and economic development, the civil aviation industry of China is experiencing rapid growth. This growth will lead to more CO2 emissions. Carbon dioxide emissions and greenhouse effect are already serious problems especially in China, but also all over the world. Civil aviation has brought environmental pollution in the context of improving social activity and economic growth. Because of civil aviation, the rapid increase of the total amount of air pollutants are also in...

  17. 1-(3-sulfonic acid group) propyl piperidinium dodecylbenzenesulfonic acid applied in carbon dioxide capture%1-(3-磺酸基)丙基哌啶十二烷基苯磺酸在CO2捕集中的应用∗

    Institute of Scientific and Technical Information of China (English)

    李工; 丁嘉; 郭剑桥; 徐小军; 王树立; 余益松

    2015-01-01

    A surface active functional ionic liquid, 1⁃(3⁃sulfonic acid group) propyl piperidinium dodecylbenzenesulfonic acid ([ PIPS] DBSA) was synthesized and characterized by 1H NMR, FTIR, and element analysis. [ PIPS] DBSA was used to promote the formation of carbon dioxide hydrate, and its effect on the temperature and pressure was investigated. Experimental results show that, by comparing 300 mg·L-1 [ PIPS ] DBSA solution with the 700 mg·kg-1 sodium dodecylbenzenesulfonate solution( SDBS) , the phase equilibrium pressure of carbon dioxide hydrate was decreased by 13.60% —14.96% in the range of 4℃ —6℃, and the required time for steady CO2 pressure was reduced by 50 min at 4 ℃. The investigation indicated that [ PIPS] DBSA has a good promotion effect on the formation of cardon dioxide hydrate.%合成了一种具有表面活性功能的离子液体1⁃(3⁃磺酸基)丙基哌啶十二烷基苯磺酸([PIPS]DBSA),采用FT⁃IR,1 H NMR 和元素分析等方法对产物进行表征,并将其用于促进 CO2水合物的生成,考察[ PIPS] DBSA对CO2水合物生成过程中温度和压力的影响.实验表明在温度4℃—6℃时,300 mg·L-1[ PIPS] DBSA溶液中CO2的相平衡压力比700 mg·L-1的十二烷基苯磺酸钠( SDBS)溶液的相平衡压力下降了13�6%—14.96%.在4℃时,300 mg·L-1[ PIPS] DBSA溶液中CO2压力稳定所用的时间与700 mg·L-1 SDBS溶液相比减少了50 min,表明[ PIPS] DBSA对CO2水合物的形成具有良好的促进作用.

  18. Chemoselective Synthesis of Carbamates using CO2 as Carbon Source.

    Science.gov (United States)

    Riemer, Daniel; Hirapara, Pradipbhai; Das, Shoubhik

    2016-08-01

    Synthesis of carbamates directly from amines using CO2 as the carbon source is a straightforward and sustainable approach. Herein, we describe a highly effective and chemoselective methodology for the synthesis of carbamates at room temperature and atmospheric pressure. This methodology can also be applied to protect the amino group in amino acids and peptides, and also to synthesize important pharmaceuticals. PMID:27376902

  19. CyclicCO2R: production of cyclic carbonates from CO2 using renewable feedstocks

    OpenAIRE

    Kimball, E; Schuurbiers, C.A.H.; Zevenbergen, J.F.; Håkonsen, S.F.; Heyn, R.; Offermans, W.; Leitner, W.; Ostapowicz, T.; Müller, T. E.; Mul, G.; North, M.; Ngomsik-Fanselow, A.F.; Sarron, E.; Sigurbjörnsson, O.; Schäffner, B.

    2013-01-01

    The consortium behind CyclicCO2R wants to kick-start the implementation of CO2 utilization technologies by converting CO2 into a high value-added product, thus providing a showcase that inspires industry to further develop technologies utilizing CO2 as a sustainable raw material and valorizing CO2 in such a way that drives the market for CO2 capture and utilization.

  20. Effects of nitrogen addition and precipitation change on soil methane and carbon dioxide fluxes%施氮和降水格局改变对土壤CH4和CO2通量的影响

    Institute of Scientific and Technical Information of China (English)

    李伟; 白娥; 李善龙; 孙建飞; 彭勃; 姜萍

    2013-01-01

    ,and even,converted the CH4 consumption into CH4 release.However,this inhibition effect only lasted for approximately 5 days.Nitrogen addition also affected the relationships between the CH4 flux and environmental factors (soil temperature,pH,and clay content) to some extent.The changed precipitation regime had no significant effects on the CH4 flux.Nitrogen addition decreased the CO2 flux,with an average decrement of 27.4% after 4 years continuous nitrogen addition.It was predicted that the effects of long-term continuous nitrogen addition on the CO2 flux would be increased with time,and reached the maximum after certain years of nitrogen addition.Oppositely,the effects of single time nitrogen addition would be decreased with time,and disappeared by the end of the 1-month cycle.The inhibition effect of nitrogen addition on the CO2 flux was negatively correlated with soil water filled pore space (WFPS) (P =0.022),and enhanced and extended at higher temperature.Nitrogen addition and precipitation change could possibly alter the temperature sensitivity of soil respiration.Our results indicated that the soil nitrogen in temperate forest in Changbai Mountains had not reached a threshold,and the future nitrogen deposition increase would inhibit the CO2 release and CH4 uptake.Overall,nitrogen addition would inhibit the soil carbon release.

  1. CarbFix I: Rapid CO2 mineralization in basalt for permanent carbon storage

    Science.gov (United States)

    Matter, J. M.; Stute, M.; Snæbjörnsdóttir, S.; Gíslason, S. R.; Oelkers, E. H.; Sigfússon, B.; Gunnarsson, I.; Aradottir, E. S.; Gunnlaugsson, E.; Broecker, W. S.

    2015-12-01

    Carbon dioxide mineralization via CO2-fluid-rock reactions provides the most permanent solution for geologic CO2 storage. Basalts, onshore or offshore, have the potential to store million metric tons of CO2 as (Ca, Mg, Fe) carbonates [1, 2]. However, as of today it was unclear how fast CO2 is converted to carbonate minerals in-situ in a basalt storage reservoir. The CarbFix I project in Iceland was designed to verify in-situ CO2 mineralization in basaltic rocks. Two injection tests were performed at the CarbFix I pilot injection site near the Hellisheidi geothermal power plant in 2012. 175 tons of pure CO2 and 73 tons of a CO2+H2S mixture were injection from January to March 2012 and in June 2013, respectively. The gases were injected fully dissolved in groundwater into a permeable basalt formation between 400 and 800 m depth using a novel CO2 injection system. Using conservative (SF6, SF5CF3) and reactive (14C) tracers, we quantitatively monitor and detect dissolved and chemically transformed CO2. Tracer breakthrough curves obtained from the first monitoring well indicate that the injected solution arrived in a fast short pulse and a late broad peak. Ratios of 14C/SF6, 14C/SF5CF3 or DIC/SF6 and DIC/SF5CF3 are significantly lower in the monitoring well compared to the injection well, indicating that the injected dissolved CO2 reacted. Mass balance calculations using the tracer data reveal that >95% of the injected CO2 has been mineralized over a period of two years. Evidence of carbonate precipitation has been found in core samples that were collected from the storage reservoir using wireline core drilling as well as in and on the submersible pump in the monitoring well. Results from the core analysis will be presented with emphasis on the CO2 mineralization. [1] McGrail et al. (2006) JGR 111, B12201; [2] Goldberg et al. (2008) PNAS 105(29), 9920-9925.

  2. Does carbon dioxide pool or stream in the subsurface?

    CERN Document Server

    Cardoso, Silvana S S

    2014-01-01

    Pools of carbon dioxide are found in natural geological accumulations and in engineered storage in saline aquifers. It has been thought that once this CO2 dissolves in the formation water, making it denser, convection streams would transport it efficiently to depth, but this may not be so. Here, we assess the impact of natural chemical reactions between the dissolved CO2 and the rock formation on the convection streams in the subsurface. We show that, while in carbonate rocks the streaming of dissolved carbon dioxide persists, the chemical interactions in silicate-rich rocks may curb this transport drastically and even inhibit it altogether. New laboratory experiments confirm the curtailing of convection by reaction. Wide and narrow streams of dense carbon-rich water are shut-off gradually as reaction strength increases until all transport of the pooled carbon dioxide occurs by slow molecular diffusion. These results show that the complex fluid dynamic and kinetic interactions between pooled carbon dioxide an...

  3. Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Ronald H. Brown Repeat Hydrography Cruise in the Atlantic Ocean: CLIVAR CO2 Section A16S_2005 (11 January - 24 February, 2005)

    Energy Technology Data Exchange (ETDEWEB)

    Kozyr, Alex [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Carbon Dioxide Information Analysis Center

    2006-08-30

    This report presents methods, and analytical and quality control procedures for salinity, oxygen, nutrient, inorganic carbon, organic carbon, chlorofluorocarbon (CFC), and bomb 14C system parameters performed during the A16S_2005 cruise, which took place from January 11 to February 24, 2005, aboard research vessel (R/V) Ronald H. Brown under the auspices of the National Oceanic and Atmospheric Administration (NOAA). The R/V Ronald H. Brown departed Punta Arenas, Chile, on January 11, 2005, and ended its cruise in Fortaleza, Brazil, on February 24, 2005. The research conducted was one of a series of repeat hydrography sections jointly funded by NOAA and the National Science Foundation as part of the CLIVAR/CO2/repeat hydrography/tracer program. Samples were taken from 36 depths at 121 stations. The data presented in this report include the analyses of water samples for total inorganic carbon (TCO2), fugacity of CO2 (fCO2), total alkalinity (TALK), pH, dissolved organic carbon (DOC), CFC, 14C, hydrographic, and other chemical measurements. The R/V Ronald H. Brown A16S_2005 data set is available free of charge as a numeric data package (NDP) from the Carbon Dioxide Information Analysis Center (CDIAC). The NDP consists of the oceanographic data files and this printed documentation, which describes the procedures and methods used to obtain the data.

  4. Design and Implementation of a CO2 Flood Utilizing Advanced Reservoir Characterization and Horizontal Injection Wells In a Shallow Shelf Carbonate Approaching Waterflood Depletion, Class II; ANNUAL

    International Nuclear Information System (INIS)

    The principle objective of this project is to demonstrate the economic viability and widespread applicability of an innovative reservoir management and carbon dioxide (CO2) flood project development approach for improving CO2 flood project economics in shallow shelf carbonate (SSC) reservoirs

  5. High CO2 subsurface environment enriches for novel microbial lineages capable of autotrophic carbon fixation

    Science.gov (United States)

    Probst, A. J.; Jerett, J.; Castelle, C. J.; Thomas, B. C.; Sharon, I.; Brown, C. T.; Anantharaman, K.; Emerson, J. B.; Hernsdorf, A. W.; Amano, Y.; Suzuki, Y.; Tringe, S. G.; Woyke, T.; Banfield, J. F.

    2015-12-01

    Subsurface environments span the planet but remain little understood from the perspective of the capacity of the resident organisms to fix CO2. Here we investigated the autotrophic capacity of microbial communities in range of a high-CO2 subsurface environments via analysis of 250 near-complete microbial genomes (151 of them from distinct species) that represent the most abundant organisms over a subsurface depth transect. More than one third of the genomes belonged to the so-called candidate phyla radiation (CPR), which have limited metabolic capabilities. Approximately 30% of the community members are autotrophs that comprise 70% of the microbiome with metabolism likely supported by sulfur and nitrogen respiration. Of the carbon fixation pathways, the Calvin Benson Basham Cycle was most common, but the Wood-Ljungdhal pathway was present in the greatest phylogenetic diversity of organisms. Unexpectedly, one organism from a novel phylum sibling to the CPR is predicted to fix carbon by the reverse TCA cycle. The genome of the most abundant organism, an archaeon designated "Candidatus Altiarchaeum hamiconexum", was also found in subsurface samples from other continents including Europe and Asia. The archaeon was proven to be a carbon fixer using a novel reductive acetyl-CoA pathway. These results provide evidence that carbon dioxide is the major carbon source in these environments and suggest that autotrophy in the subsurface represents a substantial carbon dioxide sink affecting the global carbon cycle.

  6. Six-fold coordinated carbon dioxide VI.

    Science.gov (United States)

    Iota, Valentin; Yoo, Choong-Shik; Klepeis, Jae-Hyun; Jenei, Zsolt; Evans, William; Cynn, Hyunchae

    2007-01-01

    Under standard conditions, carbon dioxide (CO2) is a simple molecular gas and an important atmospheric constituent, whereas silicon dioxide (SiO2) is a covalent solid, and one of the fundamental minerals of the planet. The remarkable dissimilarity between these two group IV oxides is diminished at higher pressures and temperatures as CO2 transforms to a series of solid phases, from simple molecular to a fully covalent extended-solid V, structurally analogous to SiO2 tridymite. Here, we present the discovery of an extended-solid phase of CO2: a six-fold coordinated stishovite-like phase VI, obtained by isothermal compression of associated CO2-II (refs 1,2) above 50 GPa at 530-650 K. Together with the previously reported CO2-V (refs 3-5) and a-carbonia, this extended phase indicates a fundamental similarity between CO2 (a prototypical molecular solid) and SiO2 (one of Earth's fundamental building blocks). We present a phase diagram with a limited stability domain for molecular CO2-I, and suggest that the conversion to extended-network solids above 40-50 GPa occurs via intermediate phases II (refs 1,2), III (refs 7,8) and IV (refs 9,10). The crystal structure of phase VI suggests strong disorder along the c axis in stishovite-like P42/mnm, with carbon atoms manifesting an average six-fold coordination within the framework of sp3 hybridization. PMID:17160005

  7. The effect of atmospheric CO2 concentration on carbon isotope fractionation in C3 land plants

    Science.gov (United States)

    Schubert, Brian A.; Jahren, A. Hope

    2012-11-01

    Because atmospheric carbon dioxide is the ultimate source of all land-plant carbon, workers have suggested that pCO2 level may exert control over the amount of 13C incorporated into plant tissues. However, experiments growing plants under elevated pCO2 in both chamber and field settings, as well as meta-analyses of ecological and agricultural data, have yielded a wide range of estimates for the effect of pCO2 on the net isotopic discrimination (Δδ13Cp) between plant tissue (δ13Cp) and atmospheric CO2 (δ13CCO2). Because plant stomata respond sensitively to plant water status and simultaneously alter the concentration of pCO2 inside the plant (ci) relative to outside the plant (ca), any experiment that lacks environmental control over water availability across treatments could result in additional isotopic variation sufficient to mask or cancel the direct influence of pCO2 on Δδ13Cp. We present new data from plant growth chambers featuring enhanced dynamic stabilization of moisture availability and relative humidity, in addition to providing constant light, nutrient, δ13CCO2, and pCO2 level for up to four weeks of plant growth. Within these chambers, we grew a total of 191 C3 plants (128 Raphanus sativus plants and 63 Arabidopsis thaliana) across fifteen levels of pCO2 ranging from 370 to 4200 ppm. Three types of plant tissue were harvested and analyzed for carbon isotope value: above-ground tissues, below-ground tissues, and leaf-extracted nC31-alkanes. We observed strong hyperbolic correlations (R ⩾ 0.94) between the pCO2 level and Δδ13Cp for each type of plant tissue analyzed; furthermore the linear relationships previously suggested by experiments across small (10-350 ppm) changes in pCO2 (e.g., 300-310 ppm or 350-700 ppm) closely agree with the amount of fractionation per ppm increase in pCO2 calculated from our hyperbolic relationship. In this way, our work is consistent with, and provides a unifying relationship for, previous work on carbon isotopes

  8. Kinetics of carbonate dissolution in CO2-saturated aqueous system at reservoir conditions

    Science.gov (United States)

    Peng, Cheng; Crawshaw, John P.; Maitland, Geoffrey; Trusler, J. P. Martin

    2014-05-01

    results of the study indicate that the rotating disc technique can allow accurate measurement of the carbonate dissolution rate under surface-reaction-controlled conditions, and that the carbonate dissolution rate typically increases with the increase of temperature, CO2 partial pressure and solution acidity. The study shows that the dissolution of carbonate in CO2-free acidic solutions can be described as a first order heterogeneous reaction; however, this model is not sufficient to describe the reaction kinetics of carbonate minerals in the (CO2 + H2O) system, particularly for high reactivity carbonates, such as calcite, at reservoir conditions. For these systems, both pH and the activity of CO2(aq) influence the dissolution rate. Based on the experimental results, kinetic models have been developed and parameterised to describe the dissolution of different carbonate minerals. The results of this study should facilitate more rigorous modelling of mineral dissolution in deep saline aquifers used for CO2 storage. We gratefully acknowledge the funding of QCCSRC provided jointly by Qatar Petroleum, Shell, and the Qatar Science & Technology Park. Keywords: Carbon Dioxide, Carbonate, High Pressure, High Temperature, Reaction Kinetics.

  9. Accuracy of transcutaneous carbon dioxide tension measurements during cardiopulmonary exercise testing.

    NARCIS (Netherlands)

    Stege, G.; Elshout, F.J.J. van den; Heijdra, Y.F.; Ven, M.J.T. van de; Dekhuijzen, P.N.R.; Vos, P.J.E.

    2009-01-01

    BACKGROUND: Measurements of transcutaneous carbon dioxide tension (PtcCO(2)) with current devices are proven to provide clinically acceptable agreement with measurements of partial arterial carbon dioxide tension (PaCO(2)) in several settings but not during cardiopulmonary exercise testing (CPET). O

  10. Experimental studies on removal of carbon dioxide by aqueous ammonia fine spray

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Experimental studies on carbon dioxide capture in a spray scrubber were carried out.Fine spray of aqueous ammonia was used as CO2 absorbent.Effects of different operating and design parameters on CO2 removal efficiency including concentration of aqueous ammonia,liquid flow rate,total gas flow rate,initial temperature and concentration of carbon dioxide were investigated.

  11. Palladium-Catalyzed Carbonylation of Primary Amines in Supercritical Carbon Dioxide

    Institute of Scientific and Technical Information of China (English)

    李金恒; 江焕峰; 陈鸣才

    2001-01-01

    The chemoselectity of the palladimm-catalyzed carbonylation of amines was affected by the addition of MeOH in supercritical carbon dioxide. The results show different selectivity in supercritical carbon dioxide CO2(sc) from that in alcohol.Methyl carbamate and its derivatives were obtained in high yields in CO2(sc).

  12. Process Evaluation of Carbon Dioxide Capture for Coal-Fired Power Plants

    OpenAIRE

    Satoshi Kodama; Kazuya Goto; Hidetoshi Sekiguchi

    2014-01-01

    Carbon capture is a promising technology for carbon dioxide (CO2) removal from large stationary CO2 sources. The effects of carbon dioxide capture process on output efficiency of fossil power plants were investigated. Supercritical pulverized coal and integrated coal gasification combined cycle (IGCC) were assumed as model coal-fired power plants for this investigation. Heat-driven and pressure-driven CO2 capture processes such as chemical absorption and physical adsorption were assumed for C...

  13. Carbon dioxide catastrophes: Past and future menace

    Science.gov (United States)

    Baur, Mario E.

    1988-01-01

    Carbon dioxide is important in its role as coupler of the terrestrial biosphere to inorganic chemical processes and as the principal greenhouse gas controlling Earth's surface temperature. The hypothesis that atmospheric CO2 levels have diminished with time, with the resulting cooling effect offsetting an increase in the solar constant, seems firmly established, and it is shown that feedback mechanisms exist which can maintain the terrestrial surface in a relatively narrow temperature range over geological time. Of the factors involved in such CO2 variation, the oceanic reservoir appears the most important. Surface waters are probably in approximate equilibrium with regard to CO2 exchange with the ambient atmosphere in most regions, but data from deep-ocean water sampling indicates that such waters are somewhat undersaturated in the sense that they would tend to absorb CO2 from the atmosphere if brought to the surface without change in composition or temperature. If major impacts into the ocean can result in loss of a substantial portion of the atmospheric CO2 reservoir, then any such future event could imperil the continuation of most higher forms of life on Earth. The most likely candidate for an inverse Nyos global event in previous Earth history is the Cretaceous-Tertiary terminal extinction event. The Cretaceous was characterized by warm, equable temperatures presumably indicative of relatively high CO2 levels and an intense greenhouse heating. Cooling of the oceans in absence of massive transfer of CO2 to the oceanic reservoir in itself would promote a condition of CO2 undersaturation in abyssal waters, and this is made even more extreme by the pattern of ocean water circulation. It is possible to envision a situation in which deep ocean waters were at least occasionally profoundly undersaturated with regard to CO2. Turnover of a major fraction of such an ocean would then remove, on a very short time scale, as much as 90 percent of the atmospheric CO2

  14. Modeling and calculation of open carbon dioxide refrigeration system

    International Nuclear Information System (INIS)

    Highlights: • A model of open refrigeration system is developed. • The state of CO2 has great effect on Refrigeration capacity loss by heat transfer. • Refrigeration capacity loss by remaining CO2 has little relation to the state of CO2. • 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

  15. CO2 emissions: mineral carbonation and Finnish pulp and paper industry (CO2 Nordic Plus) and use of serpentinites in energy and metal industry (ECOSERP)

    International Nuclear Information System (INIS)

    Abstract Mineral carbonation has been investigated at Helsinki University of Technology (TKK), laboratory of energy engineering and environmental protection since year 2000. The Finnish Technology Agency Tekes and the Finnish Recovery Boiler Committee are funding through the ClimBus technology programme, in conjunction with the Nordic Energy Research Programme, the research regarding the application of ex situ mineral carbonation processes. One aspect is to verify the possible use of mineral carbonation for the separation, utilisation and long-term storage of carbon dioxide (CO2) in the pulp and paper industry. The Geological Survey of Finland (GTK) has been screening since 2004 the location, quality and suitability of the Finnish processed serpentine and stoped serpentinite storage of mines and in situ serpentinite bodies of ultramafic rock formations for mineral carbonation of CO2. Tekes and the GTK are funding development work through the ClimBus technology programme on the utilisation of serpentine and serpentinite for CO2 sequestration purposes, based on economical and environmental evaluation of mineral and mining processing operations. Also the options for other use of serpentine and serpentinite are evaluated. The most promising magnesium- and calcium-based sources for carbonation are by-products of mining processes of ultramafic rocks (such as serpentinites and serpentine) and steelmaking slags. Carbonated minerals could possibly be used as paper coating materials (PCC), fillers or construction materials. For magnesium carbonate new markets and applications must be developed. (orig.)

  16. 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. PMID:26802362

  17. Flue gas CO2 mineralization using thermally activated serpentine: from single- to double-step carbonation.

    Science.gov (United States)

    Werner, Mischa; Hariharan, Subrahmaniam; Mazzotti, Marco

    2014-12-01

    Carbon dioxide capture and utilization by mineralization seeks to combine greenhouse gas emission control with the production of value-added materials in the form of solid carbonates. This experimental work demonstrates that the world's most abundant mineralization precursor, the magnesium (Mg) silicate serpentine, in its thermally activated, partially dehydroxylated form can be carbonated without the use of chemical additives at process temperatures (T) below 90 °C and CO2 partial pressures (pCO2) below 1 bar. A first series of single-step batch experiments was performed varying the temperature and slurry density to systematically assess the precipitation regime of the relevant Mg-carbonates and the fate of silicon (Si) species in solution. The results suggested that the reaction progress was hindered by a passivating layer of re-precipitated silica or quartz, as well as by equilibrium limitations. Concurrent grinding proved effective in tackling the former problem. A double-step strategy proved successful in addressing the latter problem by controlling the pH of the solution. This is achieved by continuously removing the Mg from the dissolution reactor and letting it precipitate at a higher T and a lower pCO2 in a separate reactor, thus yielding a combined T-pCO2-swing-the working principle of a new flue gas mineralization route is presented herein. Simulations and experiments of the different individual steps of the process are reported, in order to make an assessment of its feasibility. PMID:25327589

  18. Effect of Activation Temperature on CO2 Capture Behaviors of Resorcinol-based Carbon Aerogels

    International Nuclear Information System (INIS)

    In this study, carbon aerogel (CA) was synthesized using a soft-template method, and the optimum conditions for the adsorption of carbon dioxide (CO2) by the carbon aerogel were evaluated by controlling the activation temperature. KOH was used as the activation agent at a KOH/CA activation ratio of 4:1. Three types of activated CAs were synthesized at activation temperatures of 800 .deg. C (CA-K-800), 900 .deg. C (CA-K-900), and 1000 .deg. C (CA-K-1000), and their surface and pore characteristics along with the CO2 adsorption characteristics were examined. The results showed that with the increase in activation temperature from 800 to 900 .deg. C, the total pore volume and specific surface area sharply increased from 1.2165 to 1.2500 cm3/g and 1281 to 1526 m2/g, respectively. However, the values for both these parameters decreased at temperatures above 1000 .deg. C. The best CO2 adsorption capacity of 10.9 wt % was obtained for the CA-K-900 sample at 298 K and 1 bar. This result highlights the importance of the structural and textural characteristics of the carbon aerogel, prepared at different activation temperatures on CO2 adsorption behaviors

  19. Synergetic effect of carbon nanopore size and surface oxidation on CO2 capture from CO2/CH4 mixtures

    OpenAIRE

    Furmaniak, Sylwester; KOWALCZYK, PIOTR; Terzyk, Artur P.; Gauden, Piotr A.; Harris , P. J. F.

    2013-01-01

    We have studied the synergetic effect of confinement (carbon nanopore size) and surface chemistry (the number of carbonyl groups) on CO2 capture from its mixtures with CH4 at typical operating conditions for industrial adsorptive separation (298 K and compressed CO2CH4 mixtures). Although both confinement and surface oxidation have an impact on the efficiency of CO2/CH4 adsorptive separation at thermodynamics equilibrium, we show that surface functionalization is the most important factor in ...

  20. 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.

  1. CARBON DIOXIDE SEQUESTRATION BY ULTRAMAFIC-HOSTED MINE TAILINGS: EXAMPLE FROM JINCHUAN COPPER-NICKEL MINE TAILING%应用超基性岩尾矿封存CO2——以金川铜镍矿尾矿为例

    Institute of Scientific and Technical Information of China (English)

    李子波; 刘连文; 赵良; 季峻峰; 陈骏

    2011-01-01

    通过CO2矿物封存可以降低人类活动产生的温室气体的排放,富镁硅酸盐矿物经碳酸盐化作用转化为镁碳酸盐矿物可以实现CO2的封存,而超基性岩尾矿是CO2矿物封存的理想原料.我国可用于封存CO2的超基性岩尾矿包括铜镍矿尾矿、石棉尾矿、蛇纹石尾矿以及钒钛磁铁矿尾矿等.本文重点介绍金川铜镍矿尾矿的粒度、矿物组成、常量和微量元素,以及其自然风化固碳能力和CO2封存潜力.该研究通过对金川铜镍矿1号尾矿坝和2号尾矿坝样品的粒度、元素、红外光谱、扫描电镜、X-射线衍射以及选择性淋溶结果分析,发现1号尾矿坝和2号尾矿坝中五水菱镁矿(lansfordite)的平均含量分别为4.19wt%和1.95wt%,初步估算出金川铜镍矿尾矿自然风化固定大气中CO2的量高达70.68×10t.对尾矿中所含有价金属进行综合利用可以极大的降低CO2矿物封存成本.%Anthropogenic greenhouse gas emissions may be offset by carbon dioxide mineral sequestration, through carbonation of magnesium silicate minerals to form magnesium carbonate minerals. Ultramafic-hosted mine tailings are ideal raw material for carbon dioxide mineral sequestration. Tailings that can be used to sequestrate carbon dioxide include copper-nickel mine tailings, chrysotile mine tailings, serpentine mine tailings, and V-Ti-magnetite mine tailings in China. We analyzed the particle size, mineral composition, major elements and trace elements, and the potential and capability of natural weathering for carbon dioxide sequestration in Jinchuan copper-nickel mine tailing. Jinchuan is located in the middle of Gansu, China(38° 29'N, 102° 10'E) at an elevation of 1563m. To examine the capability of carbon dioxide fixed in Jinchuan copper-nickel mine tailing, a profile was dug in tailing Dam No. 1 and 9 samples were collected at 10cm intervals,and 5 other samples were collected from Dam No. 2.Particle size ,XRF, FT-IR, XRD, and

  2. An Experimental Study of CO2 Exsolution and Relative Permeability Measurements during CO2 Saturated Water Depressurization Relevant to Carbon Sequestration

    Science.gov (United States)

    Zuo, L.; Krevor, S. C.; Falta, R. W.; Benson, S. M.

    2011-12-01

    Saline aquifers and depleted oil and gas fields have been considered as preferred geological sequestration options for carbon dioxide to reduce greenhouse gas emissions. Given the high solubility of CO2 in water, over time, the fraction of CO2 in the subsurface may be dominated by dissolved CO2. CO2 laden brine may permeate cap rocks and carry dissolved CO2 to shallower depths, if there is an upward pressure gradient from the reservoir to the overlying groundwater aquifers. This kind of non-hydrostatic pressure gradients can be caused by gas injection in deeper formations, or groundwater depletion. Such upward flows will depressurize the brine and the dissolved CO2 will come out of solution as pressure drops. We present the results of an experimental investigation into the effects of CO2 exsolution on multiphase flow properties in a CO2-water system with various reservoir rocks and a risk assessment of CO2 leakage due to exsolution in carbon sequestration. The relative permeability of exsolved CO2 and water was measured in a core-flooding apparatus during depressurization with X-ray computed tomography. Very low relative permeabilities of CO2 and water are measured in the exsolution experiments, compared to the relative permeabilities derived from steady-state drainage measurements in the same cores, even when the CO2 saturation is as high as 40%. The large relative permeability reduction in both the CO2 and water phases is hypothesized to result from the presence of a disconnected exsolution gas phase in this flow system. After the CO2 was exsolved, a CO2-saturated water flooding experiment demonstrated the durability and the stability of the low water mobility in the presence of the exsolution gas phase, while the water mobility returned to normal after all of the exsolved CO2 dissolved by a fresh water. A large pressure drop across the core, which is 4~5 times higher than the pressure drop predicted by the drainage relative permeability, was maintained over 120

  3. CO2 Sequestraion by Mineral Carbonation of Cement Material

    Science.gov (United States)

    Jo, H.; Jang, Y.

    2010-12-01

    CO2 sequestration by mineral carbonation with cement materials was investigated in this study. Ca extraction and CO2 injection tests were conducted on three different materials (lime, Portland cement, waste concrete) using different extract reagents (NH4Cl, CH3COOH, HCl, and Deionized water) under ambient temperature and pressure conditions. CO2 gas (99.9%) was injected to either supernatant without solids or suspension with solids obtained from extraction tests at 4 ml/min of flow rate. Ca concentrations were measured from filtered solutions before and after CO2 injection. The chemical and mineralogical composition of raw materials and precipitates were determined using X-ray fluorescence and X-ray diffraction, respectively. The morphology and chemical composition of precipitates were analyzed with Field Emission Scanning Electron Microscopy equipped with the Energy Dispersive X-ray analysis. For the extraction tests, Ca concentrations of the extracts were related with the CaO content and type of CaO bearing minerals of the materials, regardless of the extraction solutions. Lime had a higher Ca concentration ranging between 942.7 and 39945.0 mg/L in the extracts than waste concrete (188.4 ~ 2978.1 mg/L) in the extracts due to its higher content of CaO (CaO : 24.5% and waste concrete : 20.3%). In contrast, the Portland cement (6346.0 and 28903.5 mg/L) had lower Ca concentrations than lime (94.27 ~ 39945.0 mg/L), even though the Portland cement (56.3%) had a higher CaO content than lime (24.5%). For a given extraction solution, lime had the highest CO2 carbonation efficiency. In addition, for a given material, the CO2 carbonation efficiency was the highest when NH4Cl solution was used as an extraction solution. Results of material analyses indicate that precipitates from the CO2 injection tests consisted of mostly CaCO3, regardless of types of materials and extraction solutions.

  4. Photocatalytic and Electrocatalytic Reduction of Carbon Dioxide in Pressurized Systems

    OpenAIRE

    Voyame, Patrick

    2016-01-01

    The depletion of carbon-based fossil fuels and the rise in atmospheric carbon dioxide concentration will force an inevitable change in the future global energy landscape. CO2 reduction presents the advantages of decreasing its atmospheric concentration and storing energy in chemical form in CO2 reduction products. With a predicted conversion to renewable energy such as solar or wind energy, energy storage will become a key process in the near future for buffering the fluctuating energy produc...

  5. Influence of Carbonic Anhydrase Activity in Terrestrial Vegetation on the 18O Content of Atmospheric CO2

    Science.gov (United States)

    Gillon, Jim; Yakir, Dan

    2001-03-01

    The oxygen-18 (18O) content of atmospheric carbon dioxide (CO2) is an important indicator of CO2 uptake on land. It has generally been assumed that during photosynthesis, oxygen in CO2 reaches isotopic equilibrium with oxygen in 18O-enriched water in leaves. We show, however, large differences in the activity of carbonic anhydrase (which catalyzes CO2 hydration and 18O exchange in leaves) among major plant groups that cause variations in the extent of 18O equilibrium (θeq). A clear distinction in θeq between C3 trees and shrubs, and C4 grasses makes atmospheric C18OO a potentially sensitive indicator to changes in C3 and C4 productivity. We estimate a global mean θeq value of ~0.8, which reasonably reconciles inconsistencies between 18O budgets of atmospheric O2 (Dole effect) and CO2.

  6. Carbon dioxide vs. air insufflation in ileo-colonoscopy and in gastroscopy plus ileo-colonoscopy: a comparative study Insuflación de CO2 vs. aire en íleo-colonoscopia y en gastroscopia más íleo-colonoscopia: estudio comparativo

    Directory of Open Access Journals (Sweden)

    María Fernández-Calderón

    2012-05-01

    Full Text Available Introduction: insufflation with carbon dioxide (CO2 during endoscopies compared to air is associated with a decrease in abdominal discomfort after the examination, because CO2 is readily absorbed through the small intestine and eliminated by the lungs. Aims: the objective of this randomized clinical trial was to assess the effect of CO2 insufflation on pain and abdominal distension after an ileo-colonoscopy (I and after an ileo-colonoscopy plus gastroscopy (I+G. Material and methods: we included a total of 309 patients in the study and all endoscopies were performed under sedation with propofol. Two hundred fourteen patients underwent an I (132 with CO2 / 82 with air and 95 underwent an I+G (53 with CO2 / 42 with air. Abdominal pain was studied at 10, 30 and 120 minutes of exploration and abdominal perimeter difference before and after the procedure. Results: both in group I and in group I+G, the use of CO2 translated into an average of abdominal pain significantly lower (p Introducción: la insuflación con dióxido de carbono (CO2 durante las endoscopias digestivas comparado con el aire, se asocia a una disminución de las molestias abdominales después de la exploración, ya que el CO2 es fácilmente absorbido por el intestino delgado y eliminado por los pulmones. Objetivo: el objetivo de este ensayo clínico aleatorizado fue valorar el efecto de la insuflación de CO2 sobre el dolor y la distensión abdominal después de una ileo-colonoscopia (I y después de una íleo-colonoscopia + gastroscopia (I+G. Material y métodos: se incluyeron un total de 309 pacientes en el estudio y todas las endoscopias fueron realizadas bajo sedación con propofol. A 214 pacientes se les realizó una I (132 con CO2 / 82 con aire y a 95 se les realizó una I+G (53 con CO2 / 42 con aire. Se estudió el dolor abdominal a los 10, 30 y 120 min de la exploración y la diferencia de perímetro abdominal antes y después del procedimiento. Resultados: tanto en el grupo

  7. Nuclear power and the carbon dioxide problem

    International Nuclear Information System (INIS)

    This study deals with the question, which contribution can be delivered by nuclear power to the redution of the emission of carbon dioxide (CO2) from the power supply. The emphasis lays upon the following aspects: the emissions of CO2 which occur in the nuclear-power cycle (the so-called indirect emission of CO2 power plants); the amount of uranium stocks; the change of CO2 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 CO2 uranium can be calculated. The role of nuclear power in the reduction of CO2 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 CO2, 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 CO2 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 CO2 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

  8. Carbon dioxide removal in gas treating processes

    International Nuclear Information System (INIS)

    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 CO2 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 140oC, for CO2 loadings from 0.001 to 1 mol/mol, and for amine molarities usually encountered in acid gas treating processes. The absorption of CO2 into solutions containing the sterically hindered amine AMP, is also well described by the model. The equilibrium of CO2 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 CO2/TEG/MEA system for estimation of CO2 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

  9. 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.

  10. Delrin registered for Propulsion with CO2 Laser: Carbon Doping Effects

    International Nuclear Information System (INIS)

    Polyoxymethylene (POM) a.k.a. Delrin has been commonly used for propulsion with carbon dioxide (CO2) lasers as a solid fuel providing excellent combination of coupling coefficient and specific impulse. In this paper the propulsive characteristics of white and black (carbon-doped) Delrin will be examined and compared. A Transverse Electric discharge in gas at Atmospheric pressure (TEA) CO2 laser with 300 ns pulse width was operated at up to 20 J pulse energy to produce irradiances on the order of 1-500 MW/cm2 on Delrin targets. Fourier Transform Infrared (FTIR) spectroscopy, time-resolved force sensors, a ballistic pendulum, and Schlieren imaging techniques were used to determine absorption spectra, coupling coefficient, specific impulse, and internal efficiency of Delrin. An analysis will be made of the possible routes for force generation

  11. CO2 activation and carbonate intermediates: an operando AP-XPS study of CO2 electrolysis reactions on solid oxide electrochemical cells.

    Science.gov (United States)

    Yu, Yi; Mao, Baohua; Geller, Aaron; Chang, Rui; Gaskell, Karen; Liu, Zhi; Eichhorn, Bryan W

    2014-06-21

    Through the use of ambient pressure X-ray photoelectron spectroscopy and specially designed ceria-based solid oxide electrochemical cells, carbon dioxide (CO2) electrolysis reactions (CO2 + 2e(-)→ CO + O(2-)) and carbon monoxide (CO) electro-oxidation reactions (CO + O(2-)→ CO2 + 2e(-)) over cerium oxide electrodes have been investigated in the presence of 0.5 Torr CO-CO2 gas mixtures at ∼600 °C. Carbonate species (CO3(2-)) are identified on the ceria surface as reaction intermediates. When CO2 electrolysis is promoted on ceria electrodes at +2.0 V applied bias, we observe a higher concentration of CO3(2-) over a 400 μm-wide active region on the ceria surface, accompanied by Ce(3+)/Ce(4+) redox changes. This increase in the CO3(2-) steady-state concentration suggests that the process of pre-coordination of CO2 to the ceria surface to form a CO3(2-) intermediate (CO2(g) + O(2-)(surface)→ CO3(2-)(surface)) precedes a rate-limiting electron transfer process involving CO3(2-) reduction to give CO and oxide ions (CO3(2-)(surface) + 2Ce(3+)→ CO(g) + 2O(2-)(surface) + 2Ce(4+)). When the applied bias is switched to -1.5 V to promote CO electro-oxidation on ceria, the surface CO3(2-) concentration slightly decreases from the equilibrium value, suggesting that the electron transfer process is also a rate-limiting process in the reverse direction. PMID:24806971

  12. CO2 Utilization For Mechanochemical Carbonation Of Celestine

    Directory of Open Access Journals (Sweden)

    Turianicova Erika

    2015-09-01

    Full Text Available Natural celestine (SrSO4 has been succesfully transformed into strontianite (SrCO3 via fast one-step mechanochemical carbonation utilizing gaseous CO2. The process was realized in the environment enriched with LiOH or NaOH additives. The mixtures were milled in a high-energy planetary ball mill for 40 min. The phases formed during the milling were characterized by different characterization techniques, such as X-ray diffraction (XRD and infrared spectroscopy (FT-IR. The presence or absence of carbon or sulphur in the products was confirmed by a CHNS analysis.

  13. Carbon dioxide utilisation in anaerobic digesters as an on-site carbon revalorisation strategy

    OpenAIRE

    Bajón Fernández, Yadira

    2014-01-01

    The increasing carbon footprint of the water and organic waste sectors has led to water utilities to voluntarily include carbon mitigation approaches within their strategic plans and to an increase in research aimed at mitigating carbon dioxide (CO2) emissions. Injection of CO2 in anaerobic digesters (ADs) for its bioconversion into methane (CH4) has been identified as a potential solution. However, previous literature provided limited knowledge of the carbon benefits obtainable and presented...

  14. Amazon river carbon dioxide outgassing fuelled by wetlands

    OpenAIRE

    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 ecosystems(2). 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 ...

  15. Synthesis of dimethyl carbonate in supercritical carbon dioxide

    Directory of Open Access Journals (Sweden)

    D. Ballivet-Tkatchenko

    2006-03-01

    Full Text Available The reactivity of carbon dioxide with methanol to form dimethyl carbonate was studied in the presence of the n-butylmethoxytin compounds n-Bu3SnOCH3, n-Bu2Sn(OCH32 , and [n-Bu2(CH3OSn]2 O. The reaction occurred under solventless conditions at 423 K and was produced by an increase in CO2 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 CO2 pressure higher than 16 MPa. Under these conditions, CO2 acted as a reactant and a solvent.

  16. Carbon Dioxide Reduction Technology Trade Study

    Science.gov (United States)

    Jeng, Frank F.; Anderson, Molly S.; Abney, Morgan B.

    2011-01-01

    For long-term human missions, a closed-loop atmosphere revitalization system (ARS) is essential to minimize consumables. A carbon dioxide (CO2) reduction technology is used to reclaim oxygen (O2) from metabolic CO2 and is vital to reduce the delivery mass of metabolic O2. A key step in closing the loop for ARS will include a proper CO2 reduction subsystem that is reliable and with low equivalent system mass (ESM). Sabatier and Bosch CO2 reduction are two traditional CO2 reduction subsystems (CRS). Although a Sabatier CRS has been delivered to International Space Station (ISS) and is an important step toward closing the ISS ARS loop, it recovers only 50% of the available O2 in CO2. A Bosch CRS is able to reclaim all O2 in CO2. However, due to continuous carbon deposition on the catalyst surface, the penalties of replacing spent catalysts and reactors and crew time in a Bosch CRS are significant. Recently, technologies have been developed for recovering hydrogen (H2) from Sabatier-product methane (CH4). These include methane pyrolysis using a microwave plasma, catalytic thermal pyrolysis of CH4 and thermal pyrolysis of CH4. Further, development in Sabatier reactor designs based on microchannel and microlith technology could open up opportunities in reducing system mass and enhancing system control. Improvements in Bosch CRS conversion have also been reported. In addition, co-electrolysis of steam and CO2 is a new technology that integrates oxygen generation and CO2 reduction functions in a single system. A co-electrolysis unit followed by either a Sabatier or a carbon formation reactor based on Bosch chemistry could improve the overall competitiveness of an integrated O2 generation and CO2 reduction subsystem. This study evaluates all these CO2 reduction technologies, conducts water mass balances for required external supply of water for 1-, 5- and 10-yr missions, evaluates mass, volume, power, cooling and resupply requirements of various technologies. A system

  17. Carbon dioxide embolism during laparoscopic sleeve gastrectomy

    Directory of Open Access Journals (Sweden)

    Amir Abu Zikry

    2011-01-01

    Full Text Available Bariatric restrictive and malabsorptive operations are being carried out in most countries laparoscopically. Carbon dioxide or gas embolism has never been reported in obese patients undergoing bariatric surgery. We report a case of carbon dioxide embolism during laparoscopic sleeve gastrectomy (LSG in a young super obese female patient. Early diagnosis and successful management of this complication are discussed. An 18-year-old super obese female patient with enlarged fatty liver underwent LSG under general anesthesia. During initial intra-peritoneal insufflation with CO 2 at high flows through upper left quadrant of the abdomen, she had precipitous fall of end-tidal CO 2 and SaO 2 % accompanied with tachycardia. Early suspicion led to stoppage of further insufflation. Clinical parameters were stabilized after almost 30 min, while the blood gas analysis was restored to normal levels after 1 h. The area of gas entrainment on the damaged liver was recognized by the surgeon and sealed and the surgery was successfully carried out uneventfully. Like any other laparoscopic surgery, carbon dioxide embolism can occur during bariatric laparoscopic surgery also. Caution should be exercised when Veress needle is inserted through upper left quadrant of the abdomen in patients with enlarged liver. A high degree of suspicion and prompt collaboration between the surgeon and anesthetist can lead to complete recovery from this potentially fatal complication.

  18. Materials for carbon dioxide separation

    International Nuclear Information System (INIS)

    The CO2 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 CO2 adsorption ability. Another promising class of materials for CO2 capture and separation are CaO derived from the eggshells. Two aspects were studied in present work: a new hybrid materials synthesized by doping the CaTiO3 and the relationship between physisorption and chemisorption properties of CaO-based materials.

  19. Disintegration of Carbon Dioxide Molecules in a Microwave Plasma Torch

    Science.gov (United States)

    Kwak, Hyoung S.; Uhm, Han S.; Hong, Yong C.; Choi, Eun H.

    2015-12-01

    A pure carbon dioxide torch is generated by making use of 2.45 GHz microwave. Carbon dioxide gas becomes the working gas and produces a stable carbon dioxide torch. The torch volume is almost linearly proportional to the microwave power. Temperature of the torch flame is measured by making use of optical spectroscopy and thermocouple. Two distinctive regions are exhibited, a bright, whitish region of high-temperature zone and a bluish, dimmer region of relatively low-temperature zone. Study of carbon dioxide disintegration and gas temperature effects on the molecular fraction characteristics in the carbon dioxide plasma of a microwave plasma torch under atmospheric pressure is carried out. An analytical investigation of carbon dioxide disintegration indicates that substantial fraction of carbon dioxide molecules disintegrate and form other compounds in the torch. For example, the normalized particle densities at center of plasma are given by nCO2/nN = 6.12 × 10-3, nCO/nN = 0.13, nC/nN = 0.24, nO/nN = 0.61, nC2/nN = 8.32 × 10-7, nO2/nN = 5.39 × 10-5, where nCO2, nCO, nC, nO, nC2, and nO2 are carbon dioxide, carbon monoxide, carbon and oxygen atom, carbon and oxygen molecule densities, respectively. nN is the neutral particle density. Emission profiles of the oxygen and carbon atom radicals and the carbon monoxide molecules confirm the theoretical predictions of carbon dioxide disintegration in the torch.

  20. CO2 emission standards and investment in carbon capture

    International Nuclear Information System (INIS)

    Policy makers in a number of countries have proposed or are considering proposing CO2 emission standards for new fossil fuel-fired power plants. The proposed standards require coal-fired power plants to have approximately the same carbon emissions as an uncontrolled natural gas-fired power plant, effectively mandating the adoption of carbon capture and sequestration (CCS) technologies for new coal plants. However, given the uncertainty in the capital and operating costs of a commercial scale coal plant with CCS, the impact of such a standard is not apparent a priori. We apply a stochastic generation expansion model to determine the impact of CO2 emission standards on generation investment decisions, and in particular for coal plants with CCS. Moreover, we demonstrate how the incentive to invest in coal-CCS from emission standards depends on the natural gas price, the CO2 price, and the enhanced oil recovery price, as well as on the level of the emission standard. This analysis is the first to consider the entire power system and at the same time allow the capture percentage for CCS plants to be chosen from a continuous range to meet the given standard at minimum cost. Previous system level studies have assumed that CCS plants capture 90% of the carbon, while studies of individual units have demonstrated the costs of carbon capture over a continuous range. We show that 1) currently proposed levels of emission standards are more likely to shift fossil fuel generation from coal to natural gas rather than to incentivize investment in CCS; 2) tighter standards that require some carbon reductions from natural gas-fired power plants are more likely than proposed standards to incentivize investments in CCS, especially on natural gas plants, but also on coal plants at high gas prices; and 3) imposing a less strict emission standard (emission rates higher than natural gas but lower than coal; e.g., 1500 lbs/MWh) is more likely than current proposals to incentivize investment

  1. CO2 blood test

    Science.gov (United States)

    Bicarbonate test; HCO3-; Carbon dioxide test; TCO2; Total CO2; CO2 test - serum ... Many medicines can interfere with blood test results. Your health care provider will tell you if you need to stop taking any medicines before you have this test. DO ...

  2. Phase equilibrium condition of marine carbon dioxide hydrate

    International Nuclear Information System (INIS)

    Highlights: ► CO2 hydrate phase equilibrium was studied in simulated marine sediments. ► CO2 hydrate equilibrium temperature in NaCl and submarine pore water was depressed. ► Coarse-grained silica sand does not affect CO2 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.

  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. Olivine reactivity with CO 2 and H 2O on a microscale: Implications for carbon sequestration

    Science.gov (United States)

    Olsson, J.; Bovet, N.; Makovicky, E.; Bechgaard, K.; Balogh, Z.; Stipp, S. L. S.

    2012-01-01

    The silicate mineral olivine, (Mg,Fe)2SiO4, reacts exothermally with CO2 and forms secondary minerals, including carbonates. Therefore olivine reaction is a promising process for carbon sequestration, to convert carbon dioxide from the atmosphere to mineral form. The purpose of this study was (1) to explore the composition, structure and reactivity of olivine surfaces during exposure to air and to water at ambient conditions, (2) to investigate the effect of elevated CO2 pressure and temperature, and (3) to identify the secondary minerals. Olivine surfaces have been examined with atomic force microscopy (AFM), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), before and after reaction with CO2. Experiments were carried out in pure water equilibrated with CO2 at total pressures up to 80 bars, at temperatures 25 °C and 120 °C and both in the absence and presence of oxygen. New formation products appeared on the olivine surface as a homogeneous layer of bumps, less than 100 nm in diameter, within hours of exposure to air. Olivine crystals, exposed to water, dissolved and secondary minerals formed within days. Colonies of bacteria populated olivine surfaces on samples stored in water for more than 4 days at room temperature. Loosely attached material formed on olivine surfaces and could easily be scraped away with the AFM tip. A red precipitate formed when crystals where reacted at increased temperatures and CO2 partial pressures for less than 4 days. The new phases were identified as goethite, hematite, silica and carbonate minerals. Olivine surfaces oxidize and iron oxides form even when oxygen is absent, suggesting hydrolysis, where water is converted to hydrogen and oxygen.

  5. Nitrogen and Carbon Cycling in a Grassland Community Ecosystem as Affected by Elevated Atmospheric CO2

    Directory of Open Access Journals (Sweden)

    H. A. Torbert

    2012-01-01

    Full Text Available Increasing global atmospheric carbon dioxide (CO2 concentration has led to concerns regarding its potential effects on terrestrial ecosystems and the long-term storage of carbon (C and nitrogen (N in soil. This study examined responses to elevated CO2 in a grass ecosystem invaded with a leguminous shrub Acacia farnesiana (L. Willd (Huisache. Seedlings of Acacia along with grass species were grown for 13 months at CO2 concentrations of 385 (ambient, 690, and 980 μmol mol−1. Elevated CO2 increased both C and N inputs from plant growth which would result in higher soil C from litter fall, root turnover, and excretions. Results from the incubation indicated an initial (20 days decrease in N mineralization which resulted in no change in C mineralization. However, after 40 and 60 days, an increase in both C and N mineralization was observed. These increases would indicate that increases in soil C storage may not occur in grass ecosystems that are invaded with Acacia over the long term.

  6. 控制和减缓电力生产过程中CO2排放的技术%Abatement and Mitigation of Carbon Dioxide Emissions from Power Generation

    Institute of Scientific and Technical Information of China (English)

    刘彦丰; 阎维平; 丁千岭

    2000-01-01

    One important measure for controlling greenhouse gas CO2 emissions is to capture CO2 from power plant flue gas and store it or utilize it. In this paper, the principal technologies to capture CO2 are introduced,including absorption, adsorption, membrane separation and cryogenic separation. Their application in 4 kinds of power plants is analysed and compared. Some methods to store and utilize CO2 are also discussed.%直接从热力发电站的烟气中分离CO2,然后对其进行储存或加以利用,是控制和减缓温室气体排放的重要措施之一。本文描述了利用吸收、吸附、薄膜分离和低温分离等原理从热力发电站烟气中分离CO2的技术,对它们在4种发电技术上的应用做了分析比较。同时,也给出了一些有可能的储存和利用CO2的途径。

  7. CO2 Sink Effect Of Concrete Carbonation Spain

    OpenAIRE

    Galan Garcia, Isabel; Andrade Perdrix, Maria del Carmen; Mora Peris, Pedro; San Juan Barbudo, Miguel Angel; Lopez Agüi, Juan Carlos; Prieto Rabade, Miguel

    2010-01-01

    Although carbonation of cement phases is well known, the amount of carbon dioxide combined during the process has been much less investigated. Related to the greenhouse effect much more attention is being paid to the sinks for C 0 2 in order to correctly compute the gases emission during production of materials. In the case of cement a strict calculation should discount the C 0 2 emitted from that fixed by the concrete. This is the aim of present work which is a study of the cement bas...

  8. Nitric oxide is involved in the induced stomatal closure of tomato by high level of carbon dioxide%NO参与调节高浓度CO2诱导的番茄气孔关闭

    Institute of Scientific and Technical Information of China (English)

    王欢; 肖文丹; 牛耀芳; 柴如山; 刘秒; 章永松

    2015-01-01

    [Objectives]Elevated CO2 has been shown to play a role in enhancing the photosynthesis of plants, and induce stomatal closure of leaf. Stomatal closure significantly decreases plant transpiration, and contributes to enhanced water use efficiency and resistance to water stress. The effect of elevated CO2 on the aperture of stomata, the level of nitric oxide( NO) in guard cells and the role of NO in CO2 elevation-induced stomatal closure in tomato ( Solanum lycocarpum L. ) were examined. In order to identify the enzymatic source of endogenous NO in guard cells, the role of nitric oxide synthase ( NOS ) and nitrate reductase ( NR ) in the CO2 elevation-induced NO accumulation was investigated. [Methods] Tomato( Solanum lycocarpum L. ) was used as experimental material.In E7/2 growth chambers, CO2 treatments and/or pharmacological experiment were initiated by treating stomata at a concentration of either 350 or 800 μL/L. Then, the stomatal aperture and NO level in guard cells were measured. The levels of NO in guard cells of tomato were determined using the cell NO-specific fluorescent probe. NO levels in guard cells were measured based on the intensity of fluorescence. NOS inhibitor L-NAME and NR inhibitor tungstate were used to assess the role of NOS and NR in the CO2 elevation-induced NO production, respectively.[Results] The present study showed that the stomatal aperture decreased to 2. 3 μm after 6 hours of elevated CO2 treatment, and decreased by 32% related to ambient CO2 treatment. The intensity of green fluorescence showed that the level of NO in guard cells were 88% higher under elevated CO2 than that under ambient CO2 . CO2 elevation-induced stomatal closure was reversed by treatment with NO scavenger cPTIO, the level of NO in guard cells decreased by 35% and the stomatal aperture increased to 3. 2μm, similar to those under ambient CO2 . Under elevated CO2 , addition of 200 μmol/L L-NAME increased the stomatal aperture by 30%, and decreased NO

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

    International Nuclear Information System (INIS)

    The DOE program focuses on three areas each of which requires more research before the many CO2-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 CO2. Research efforts include an attempt to estimate regional and global changes in temperature and precipitation. Increased atmospheric CO2 may be a potential benefit to vegetation and crops because it is an essential element required for plant growth. Eight separate papers are included

  10. CO2 adsorption on chemically modified activated carbon.

    Science.gov (United States)

    Caglayan, Burcu Selen; Aksoylu, A Erhan

    2013-05-15

    CO2 adsorption capacity of a commercial activated carbon was improved by using HNO3 oxidation, air oxidation, alkali impregnation and heat treatment under helium gas atmosphere. The surface functional groups produced were investigated by diffuse reflectance infrared Fourier transform spectrometer (DRIFTS). CO2 adsorption capacities of the samples were determined by gravimetric analyses for 25-200°C temperature range. DRIFTS studies revealed the formation of carboxylic acid groups on the HNO3 oxidized adsorbents. Increased aromatization and uniform distribution of the Na particles were observed on the samples prepared by Na2CO3 impregnation onto HNO3 oxidized AC support. The adsorption capacities of the nonimpregnated samples were increased by high temperature helium treatments or by increasing the adsorption temperature; both leading to decomposition of surface oxygen groups, forming sites that can easily adsorb CO2. The adsorption capacity loss due to cyclic adsorption/desorption procedures was overcome with further surface stabilization of Na2CO3 modified samples with high temperature He treatments. With Na2CO3 impregnation the mass uptakes of the adsorbents at 20 bars and 25 °C were improved by 8 and 7 folds and at 1 bar were increased 15 and 16 folds, on the average, compared to their air oxidized and nitric acid oxidized supports, respectively. PMID:23500788

  11. Carbon Dioxide Corrosion:

    DEFF Research Database (Denmark)

    Fosbøl, Philip Loldrup

    2008-01-01

    CO2 corrosion is a general problem in the industry and it is expensive. The focus of this study is an oil gas production related problem. CO2 corrosion is observed in offshore natural gas transportation pipelines. A general overview of the problem is presented in chapter 1. The chemical system co...

  12. 超临界CO2萃取姜黄油的工艺研究%Study on the extraction of curcuma Longa oils with supercritical carbon dioxide

    Institute of Scientific and Technical Information of China (English)

    胡小军; 刘树兴

    2005-01-01

    本文运用均匀试验设计研究了超临界CO2流体萃取姜黄油的工艺条件,试验结果表明:最佳的萃取工艺条件为萃取压力36MPa,萃取温度50℃,CO2流量15kg/h,萃取时间3h.

  13. CO2在人体内代谢是“碱”不是“酸”%The metabolic result of carbon dioxide in human body is base instead of acid

    Institute of Scientific and Technical Information of China (English)

    汪建; 田维毅

    2015-01-01

    凡涉及人体“酸碱平衡”的教科书,都认为生物氧化产生的CO2可与H2O结合成H2CO3,是机体代谢产生最多的酸.然而CO2在人体内的主要存在形式是碱性物质HCO3-,在血液中HCO3-浓度比H2CO3高20倍,24 h由CO2转化的HCO3-是血液HCO3-含量的110倍.CO2维持了血液HCO3-的恒定,维持了血液pH=7.4;可见CO2在健康人体内发挥着碱性物质的作用.因此,CO2是碱不是酸.

  14. 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...... Menzengraben mine experienced an extreme outburst in 1953, possibly involving a several thousand tons of carbon dioxide. This source of accidents fills an important gap in the available carbon dioxide accident history and may provide a unique empirical perspective on the hazards of handling very large amounts...

  15. Carbon-13 isotope composition of the mean CO2 source in the urban atmosphere of Krakow, southern Poland

    Science.gov (United States)

    Zimnoch, Miroslaw; Jasek, Alina; Rozanski, Kazimierz

    2014-05-01

    Quantification of carbon emissions in urbanized areas constitutes an important part of the current research on the global carbon cycle. As the carbon isotopic composition of atmospheric carbon dioxide can serve as a fingerprint of its origin, systematic observations of δ13CO2 and/or Δ14CO2, combined with atmospheric CO2mixing ratio measurements can be used to better constrain the urban sources of this gas. Nowadays, high precision optical analysers based on absorption of laser radiation in the cavity allow a real-time monitoring of atmospheric CO2 concentration and its 13CO2/12CO2 ratio, thus enabling better quantification of the contribution of different anthropogenic and natural sources of this gas to the local atmospheric CO2load. Here we present results of a 2-year study aimed at quantifying carbon isotopic signature of the mean CO2 source and its seasonal variability in the urban atmosphere of Krakow, southern Poland. The Picarro G2101-i CRDS isotopic analyser system for CO2and 13CO2/12CO2 mixing ratio measurements has been installed at the AGH University of Science and Technology campus in July 2011. Air inlet was located at the top of a 20m tower mounted on the roof of the faculty building (ca. 42m a.g.l.), close to the city centre. While temporal resolution of the analyser is equal 1s, a 2-minute moving average was used for calculations of δ13CO2 and CO2 mixing ratio to reduce measurement uncertainty. The measurements were calibrated against 2 NOAA (National Oceanic and Atmospheric Administration) primary standard tanks for CO2 mixing ratio and 1 JRAC (Jena Reference Air Cylinder) isotope primary standard for δ13C. A Keeling approach based on two-component mass and isotope balance was used to derive daily mean isotopic signatures of local CO2 from individual measurements of δ13CO2 and CO2 mixing ratios. The record covers a 2-year period, from July 2011 to July 2013. It shows a clear seasonal pattern, with less negative and less variable δ13CO2 values

  16. Electrochemical CO2 reduction

    OpenAIRE

    Kriescher, Stefanie M. A.

    2015-01-01

    The atmospheric concentration of CO2 has increased significantly during the last two centuries. Since CO2 is considered to be one of the largest contributors to the greenhouse effect and is postulated to cause global warming, it is important to stabilize and/or reduce its concentration. Apart from regulations for the amount of CO2 that may be emmitted, carbon dioxide capture and storage (CCS), biological and chemical conversions are potential ways to stabilize and/or reduce the atmospheric co...

  17. Arterial and end-tidal carbon dioxide difference in pediatric intensive care

    OpenAIRE

    Chulananda Dias Goonasekera; Alison Goodwin; Yanzhong Wang; James Goodman; Akash Deep

    2014-01-01

    Background and Aim: Arterial carbon dioxide tension (PaCO 2 ) is considered the gold standard for scrupulous monitoring in pediatric intensive care unit (PICU), but it is invasive, laborious, expensive, and intermittent. The study aims to explore when we can use end-tidal carbon dioxide tension (P ET CO 2 ) as a reliable, continuous, and noninvasive monitor of arterial CO 2 Materials and Methods: Concurrent P ET CO 2 , fraction of inspired oxygen, PaCO 2 , and arterial oxygen tension values o...

  18. Highly flexible NiCo2O4/CNTs doped carbon nanofibers for CO2 adsorption and supercapacitor electrodes.

    Science.gov (United States)

    Iqbal, Nousheen; Wang, Xianfeng; Ahmed Babar, Aijaz; Yu, Jianyong; Ding, Bin

    2016-08-15

    Controllable synthesis of carbon nanofibers (CNFs) with hierarchical porosity and high flexibility are extremely desirable for CO2 adsorption and energy storage applications. Herein, we report a nickel cobaltite/carbon nanotubes doped CNFs (NiCo2O4/CNTs CNFs) mesoporous membrane that shows well-developed flexibility, tailored pore structure, hydrophobic character, and high stability. Ascribed to these unique features, NiCo2O4/CNTs CNFs membrane shows high CO2 capture of 1.54mmol/g at 25°C and 1.0bar, and electrochemical measurements for supercapacitors exhibit good performance with specific capacitances of 220F/g (in 1M KOH) at a current density of 1A/g. The successful synthesis of such hybrid membrane provides new insight into development of various multifunctional applications. PMID:27209394

  19. Enzymatic conversion of carbon dioxide.

    Science.gov (United States)

    Shi, Jiafu; Jiang, Yanjun; Jiang, Zhongyi; Wang, Xueyan; Wang, Xiaoli; Zhang, Shaohua; Han, Pingping; Yang, Chen

    2015-10-01

    With the continuous increase in fossil fuels consumption and the rapid growth of atmospheric CO2 concentration, the harmonious state between human and nature faces severe challenges. Exploring green and sustainable energy resources and devising efficient methods for CO2 capture, sequestration and utilization are urgently required. Converting CO2 into fuels/chemicals/materials as an indispensable element for CO2 capture, sequestration and utilization may offer a win-win strategy to both decrease the CO2 concentration and achieve the efficient exploitation of carbon resources. Among the current major methods (including chemical, photochemical, electrochemical and enzymatic methods), the enzymatic method, which is inspired by the CO2 metabolic process in cells, offers a green and potent alternative for efficient CO2 conversion due to its superior stereo-specificity and region/chemo-selectivity. Thus, in this tutorial review, we firstly provide a brief background about enzymatic conversion for CO2 capture, sequestration and utilization. Next, we depict six major routes of the CO2 metabolic process in cells, which are taken as the inspiration source for the construction of enzymatic systems in vitro. Next, we focus on the state-of-the-art routes for the catalytic conversion of CO2 by a single enzyme system and by a multienzyme system. Some emerging approaches and materials utilized for constructing single-enzyme/multienzyme systems to enhance the catalytic activity/stability will be highlighted. Finally, a summary about the current advances and the future perspectives of the enzymatic conversion of CO2 will be presented. PMID:26055659

  20. Effects of CO2-induced changes in seawater carbonate chemistry speciation on Coccolithus braarudii: a conceptual model of coccolithophorid sensitivities

    Directory of Open Access Journals (Sweden)

    U. Riebesell

    2010-12-01

    Full Text Available Ocean acidification and associated shifts in carbonate chemistry speciation induced by increasing levels of atmospheric carbon dioxide (CO2 have the potential to impact marine biota in various ways. The process of biogenic calcification, for instance, is usually shown to be negatively affected. In coccolithophores, an important group of pelagic calcifiers, changes in cellular calcification rates in response to changing ocean carbonate chemistry appear to differ among species. By applying a wider CO2 range we show that a species previously reported insensitive to seawater acidification, Coccolithus braarudii, responds both in terms of calcification and photosynthesis, although at higher thresholds. Thus, observed differences between species seem to be related to individual sensitivities while the underlying mechanisms could be the same. On this basis we develop a conceptual model of coccolithophorid calcification and photosynthesis in response to CO2-induced changes in seawater carbonate chemistry speciation.

  1. Net carbon storage in a popular plantation (POPFACE) after three years of free-air CO2 enrichment

    OpenAIRE

    GIELEN B.; Calfapietra, C.; Lukac, M.; Wittig, V.E.; De, Angelis, Maria; I. A. Janssens; Moscatelli, M. C.; Grego, S; Cotrufo, M. F.; Godbold, D.; M. R. Hoosbeek; Long, S.; Miglietta, F.; Polle, A.; Bernacchi, C.

    2005-01-01

    A high-density plantation of three genotypes of Populus was exposed to an elevated concentration of carbon dioxide ([CO2]; 550 µmol mol¿1) from planting through canopy closure using a free-air CO2 enrichment (FACE) technique. The FACE treatment stimulated gross primary productivity by 22 and 11% in the second and third years, respectively. Partitioning of extra carbon (C) among C pools of different turnover rates is of critical interest; thus, we calculated net ecosystem productivity (NEP) to...

  2. Development of activated carbon derived from banana peel for CO2 removal

    International Nuclear Information System (INIS)

    This research work highlights on the constraints involved in the preparation of the banana peel bio-sorbent, such as impregnation ratio, activation temperature and period of activation for reducing carbon dioxide (CO2) in the atmosphere. Micromeritics ASAP 2020 and Field Emission Scanning Electron Microscope (FESEM) were used in identifying the best sample preparation method with the largest surface area which directly contributes to the effectiveness of adsorbent in removing CO2. Sample A10 was identified to yield activated carbon with the largest surface area (260.3841 m2/g), total pore volume (0.01638 cm3/g) and pore diameter (0.2508 nm). Through nitrogen adsorption-desorption isotherm analysis, the existence of sub-micropores was proven when a combination of Type-I and Type-II isotherms were exhibited by the activated carbon produced. The results from the final adsorption test found that the material synthesized from the above mentioned parameter is capable of removing up to 1.65% wt of CO2 through adsorption at 25°C, suggesting that it can be effectively used as an adsorption material

  3. Double-walled carbon nanotube array for CO2 and SO2 adsorption.

    Science.gov (United States)

    Rahimi, Mahshid; Babu, Deepu J; Singh, Jayant K; Yang, Yong-Biao; Schneider, Jörg J; Müller-Plathe, Florian

    2015-09-28

    Grand-canonical Monte Carlo simulations and adsorption experiments are combined to find the optimized carbon nanotube (CNT) arrays for gas adsorption at low pressures and 303 K. Bundles of 3D aligned double-walled carbon nanotube (DWCNT) with inner diameter of 8 nm and different intertube distances were made experimentally. The experimental results show that decreasing intertube distance leads to a significant enhancement in carbon-dioxide (CO2) adsorption capacity at 1 bar. The molecular simulation study on CO2 adsorption onto bundles of 3D aligned DWCNT with inner diameters of 1, 3, and 8 nm and intertube distance of 0-15 nm shows that the intertube distance plays a more important role than the CNT diameter. The simulation results show that decreasing the intertube distance up to 1 nm increases the excess adsorption generally in all the studied systems at pressures 0 simulations are conducted to obtain the optimal parameters, for the DWCNT bundle, for SO2 adsorption, which are similar to those observed for CO2 in the pressure range 0 < p < 3 bars. PMID:26429026

  4. Development of activated carbon derived from banana peel for CO2 removal

    Science.gov (United States)

    Borhan, Azry; Thangamuthu, Subhashini; Taha, Mohd Faisal; Ramdan, Amira Nurain

    2015-08-01

    This research work highlights on the constraints involved in the preparation of the banana peel bio-sorbent, such as impregnation ratio, activation temperature and period of activation for reducing carbon dioxide (CO2) in the atmosphere. Micromeritics ASAP 2020 and Field Emission Scanning Electron Microscope (FESEM) were used in identifying the best sample preparation method with the largest surface area which directly contributes to the effectiveness of adsorbent in removing CO2. Sample A10 was identified to yield activated carbon with the largest surface area (260.3841 m2/g), total pore volume (0.01638 cm3/g) and pore diameter (0.2508 nm). Through nitrogen adsorption-desorption isotherm analysis, the existence of sub-micropores was proven when a combination of Type-I and Type-II isotherms were exhibited by the activated carbon produced. The results from the final adsorption test found that the material synthesized from the above mentioned parameter is capable of removing up to 1.65% wt of CO2 through adsorption at 25°C, suggesting that it can be effectively used as an adsorption material.

  5. Towards quantitave ecological risk assessment of elevated carbon dioxide levels in the marine environment

    NARCIS (Netherlands)

    Vries, de P.; Tamis, J.E.; Foekema, E.M.; Klok, T.C.; Murk, A.J.

    2013-01-01

    The environmental impact of elevated carbon dioxide (CO2) levels has become of more interest in recent years. This, in relation to globally rising CO2 levels and related considerations of geological CO2 storage as a mitigating measure. In the present study effect data from literature were collected

  6. Carbon dioxide degassing in fresh and saline water I: Degassing performance of a cascade column

    DEFF Research Database (Denmark)

    Moran, Damian

    2010-01-01

    exchange. The CO2 concentration of the influent and effluent water was measured using submersible infrared CO2 probes over an influent range of 10-60 mg L−1 CO2. Carbon dioxide degassing was quantified in terms of the mass transfer coefficient (kLa, log concentration driving force divided by packing height...

  7. Transient influence of end-tidal carbon dioxide tension on the postural restraint in cerebral perfusion

    DEFF Research Database (Denmark)

    Immink, R.V.; Truijen, J.; Secher, Niels H.;

    2009-01-01

    In the upright position, cerebral blood flow is reduced, maybe because arterial carbon dioxide partial pressure (Pa(CO(2))) decreases. We evaluated the time-dependent influence of a reduction in Pa(CO(2)), as indicated by the end-tidal Pco(2) tension (Pet(CO(2))), on cerebral perfusion during head...

  8. Carbon dioxide reduction in housing: experiences in urban renewal projects in the Netherlands

    NARCIS (Netherlands)

    Waals, F.M. van der; Vermeulen, W.J.V.; Glasbergen, P.

    2003-01-01

    It is increasingly being recognised that the housing sector can contribute to reductions in the levels of carbon dioxide (CO2 ). The renewal of existing residential areas offers opportunities to reduce CO2 emissions. However, technical options for CO2-reduction, such as insulation, solar energy, and

  9. 75 FR 18575 - Mandatory Reporting of Greenhouse Gases: Injection and Geologic Sequestration of Carbon Dioxide

    Science.gov (United States)

    2010-04-12

    ...EPA is proposing a rule to require reporting on carbon dioxide (CO2) injection and geologic sequestration (GS). The proposed rulemaking does not require control of greenhouse gases (GHGs), rather it requires only monitoring and reporting of CO2 injection and geologic sequestration. EPA first proposed that suppliers of CO2 be subject to mandatory GHG reporting......

  10. Carbon Dioxide Mitigation by Microalgal Photosynthesis

    International Nuclear Information System (INIS)

    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 CO2/mL, 10 mM ammonia, and 1 mM phosphate, with an initial pH range of 7-8

  11. Geochemical Impacts of Leaking CO2 from Subsurface Storage Reservoirs to an Unconfined Oxidizing Carbonate Aquifer

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Guohui; Qafoku, Nikolla; Lawter, Amanda R.; Bowden, Mark E.; Harvey, Omar; Sullivan, E. C.; Brown, Christopher F.

    2015-07-15

    A series of batch and column experiments combined with solid phase characterization studies (i.e., quantitative x-ray diffraction and wet chemical extractions) were conducted to address a variety of scientific issues and evaluate the impacts of the potential leakage of carbon dioxide (CO2) from deep subsurface storage reservoirs. The main objective was to gain an understanding of how CO2 gas influences: 1) the aqueous phase pH; and 2) mobilization of major, minor, and trace elements from minerals present in an aquifer overlying potential CO2 sequestration subsurface repositories. Rocks and slightly weathered rocks representative of an unconfined, oxidizing carbonate aquifer within the continental US, i.e., the Edwards aquifer in Texas, were used in these studies. These materials were exposed to a CO2 gas stream or were leached with a CO2-saturated influent solution to simulate different CO2 gas leakage scenarios, and changes in aqueous phase pH and chemical composition were measured in the liquid samples collected at pre-determined experimental times (batch experiments) or continuously (column experiments). The results from the strong acid extraction tests confirmed that in addition to the usual elements present in most soils, rocks, and sediments, the Edward aquifer samples contain As, Cd, Pb, Cu, and occasionally Zn, which may potentially be mobilized from the solid to the aqueous phase during or after exposure to CO2. The results from the batch and column experiments confirmed the release of major chemical elements into the contacting aqueous phase (such as Ca, Mg, Ba, Sr, Si, Na, and K); the mobilization and possible rapid immobilization of minor elements (such as Fe, Al, and Mn), which are able to form highly reactive secondary phases; and sporadic mobilization of only low concentrations of trace elements (such as As, Cd, Pb, Cu, Zn, Mo, etc.). The results from this experimental research effort will help in developing a systematic understanding of how CO2

  12. 不同褐煤在O2/CO2条件下燃烧特性的实验研究%Experimental study on combustion characteristics of brown coal on oxygen/carbon dioxide conditions

    Institute of Scientific and Technical Information of China (English)

    杨利

    2010-01-01

    利用热重分析仪,系统地研究了霍林河褐煤、印尼1#褐煤和印尼2#褐煤在空气和O2/CO2条件下的燃烧特性,比较了不同褐煤样品在燃烧过程中失重与温度和时间的关系.实验结果表明,褐煤在O2/CO2条件下的燃烧特性与空气条件下的燃烧特性存在明显的区别,富氧燃烧条件下CO2分压力的大小影响褐煤的反应活性.

  13. Noninvasive Measurement of Carbon Dioxide during One-Lung Ventilation with Low Tidal Volume for Two Hours: End-Tidal versus Transcutaneous Techniques

    OpenAIRE

    Zhang, Hong; Wang, Dong-Xin

    2015-01-01

    Background There may be significant difference between measurement of end-tidal carbon dioxide partial pressure (PetCO2) and arterial carbon dioxide partial pressure (PaCO2) during one-lung ventilation with low tidal volume for thoracic surgeries. Transcutaneous carbon dioxide partial pressure (PtcCO2) monitoring can be used continuously to evaluate PaCO2 in a noninvasive fashion. In this study, we compared the accuracy between PetCO2 and PtcCO2 in predicting PaCO2 during prolonged one-lung v...

  14. Hierarchical N-Doped Carbon as CO2 Adsorbent with High CO2 Selectivity from Rationally Designed Polypyrrole Precursor.

    Science.gov (United States)

    To, John W F; He, Jiajun; Mei, Jianguo; Haghpanah, Reza; Chen, Zheng; Kurosawa, Tadanori; Chen, Shucheng; Bae, Won-Gyu; Pan, Lijia; Tok, Jeffrey B-H; Wilcox, Jennifer; Bao, Zhenan

    2016-01-27

    Carbon capture and sequestration from point sources is an important component in the CO2 emission mitigation portfolio. In particular, sorbents with both high capacity and selectivity are required for reducing the cost of carbon capture. Although physisorbents have the advantage of low energy consumption for regeneration, it remains a challenge to obtain both high capacity and sufficient CO2/N2 selectivity at the same time. Here, we report the controlled synthesis of a novel N-doped hierarchical carbon that exhibits record-high Henry's law CO2/N2 selectivity among physisorptive carbons while having a high CO2 adsorption capacity. Specifically, our synthesis involves the rational design of a modified pyrrole molecule that can co-assemble with the soft Pluronic template via hydrogen bonding and electrostatic interactions to give rise to mesopores followed by carbonization. The low-temperature carbonization and activation processes allow for the development of ultrasmall pores (d carbon-based materials for various potential applications. PMID:26717034

  15. Investigation of CO2 Plume Behavior for a Large-Scale Pilot Test of Geologic Carbon Storage in a Saline Formation

    OpenAIRE

    Doughty, Christine

    2010-01-01

    The hydrodynamic behavior of carbon dioxide (CO2) injected into a deep saline formation is investigated, focusing on trapping mechanisms that lead to CO2 plume stabilization. A numerical model of the subsurface at a proposed power plant with CO2 capture is developed to simulate a planned pilot test, in which 1,000,000 metric tons of CO2 is injected over a 4-year period, and the subsequent evolution of the CO2 plume for hundreds of years. Key measures are plume migration distance and the time ...

  16. Carbon Dioxide Embolism during Laparoscopic Surgery

    OpenAIRE

    Park, Eun Young; Kwon, Ja-Young; Kim, Ki Jun

    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 ra...

  17. Catalytic Formation of Propylene Carbonate from Supercritical Carbon Dioxide/Propylene Oxide Mixture

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Propylene carbonate was synthesized from supercritical carbon dioxide (SC-CO2)/ propylene oxide mixture with phthalocyaninatoaluminium chloride (ClAlPc)/ tetrabutylammon-ium bromide (n-Bu4NBr) as catalyst. The high rate of reaction was attributed to rapid diffusion and the high miscibility of propylene oxide in SC-CO2 under employed conditions. Various reaction periods present different formation rate of propylene carbonate, mainly due to the existence of phase change during the reaction. The experimental results demonstrate that SC-CO2 could be used as not only an environmentally benign solvent but also a carbon precursor in synthesis.

  18. Potential impact of DOM accumulation on fCO2 and carbonate ion computations in ocean acidification experiments

    Directory of Open Access Journals (Sweden)

    A. Oschlies

    2012-10-01

    Full Text Available The internal consistency of measurements and computations of components of the CO2-system, namely total alkalinity (AT, total dissolved carbon dioxide (CT, CO2 fugacity (fCO2 and pH, has been confirmed repeatedly in open ocean studies when the CO2 system had been over determined. Differences between measured and computed properties, such as ΔfCO2 (= fCO2 (measured – fCO2 (computed from AT and CT / fCO2 (measured × 100, are usually below 5%. Recently, Hoppe et al. (2012 provided evidence of significantly larger ΔfCO2 in some experimental setups. These observations are currently not well understood. Here we discuss a case from a series of phytoplankton culture experiments with ΔfCO2 of up to about 25%. ΔfCO2 varied systematically during the course of these experiments and showed a clear correlation with the accumulation of dissolved organic matter (DOM. Culture and mesocosm experiments are often carried out under high initial nutrient concentrations, yielding high biomass concentrations that in turn often lead to a substantial build-up of DOM. In such experiments, DOM can reach concentrations much higher than typically observed in the open ocean. To the extent that DOM includes organic acids and bases, it will contribute to the alkalinity of the seawater contained in the experimental device. Our analysis suggests that whenever substantial amounts of DOM are produced during the experiment, standard computer programmes used to compute CO2 fugacity can underestimate true fCO2 significantly when the computation is based on AT and CT. Unless the effect of DOM-alkalinity can be accounted for, this might lead to significant errors in the interpretation of the system under consideration with respect to the experimentally applied CO2 perturbation. Errors in the inferred fCO2 can misguide the development of parameterisations used in simulations with global carbon cycle models in future CO2-scenarios. Over determination of the CO2-system in

  19. Oxygen Generation from Carbon Dioxide for Advanced Life Support

    Science.gov (United States)

    Bishop, Sean; Duncan, Keith; Hagelin-Weaver, Helena; Neal, Luke; Sanchez, Jose; Paul, Heather L.; Wachsman, Eric

    2007-01-01

    The partial electrochemical reduction of carbon dioxide (CO2) using ceramic oxygen generators (COGs) is well known and widely studied. However, complete reduction of metabolically produced CO2 (into carbon and oxygen) has the potential of reducing oxygen storage weight for life support if the oxygen can be recovered. Recently, the University of Florida devel- oped novel ceramic oxygen generators employing a bilayer elec- trolyte of gadolinia-doped ceria and erbia-stabilized bismuth ox- ide (ESB) for NASA's future exploration of Mars. The results showed that oxygen could be reliably produced from CO2 at temperatures as low as 400 C. The strategy discussed here for advanced life support systems employs a catalytic layer com- bined with a COG cell so that CO2 is reduced all the way to solid carbon and oxygen without carbon buildup on the COG cell and subsequent deactivation.

  20. SEPARATION OF HYDROGEN/CARBON DIOXIDE MIXTURES USING SUPPORTED IONIC LIQUID MEMBRANES%离子液体支撑液膜分离H2/CO2混合气体

    Institute of Scientific and Technical Information of China (English)

    刘振; 秦伟; 常庆辉

    2014-01-01

    将1-丁基-3-甲基咪唑二氰铵盐([BMIM] [DCA])、1-丁基-3-甲基咪唑苯甲酸盐([BMIM][BA])、1-丁基-3-甲基咪唑三氟甲烷磺酸盐([BMIM] [TfO])、1-丁基-3-甲基咪唑双三氟甲磺酰亚铵盐([BMIM][NTf2])等4种离子液体分别固定在PES膜中,制备成离子液体支撑液膜(SILMs)用来分离H2/CO2混合气体.实验结果表明,气体在SILMs中的渗透速率随温度的升高而增加;PES-[BMIM] [TfO]膜对H2/CO2混合气体分离能力最强,40 ℃下分离因子达15.8.利用Gaussian 09软件计算这4种离子液体与H2和CO2分子间的结合能(Ec),通过结合能的差异预测SILMs对H2/CO2的分离能力,计算与实验结果相吻合.

  1. European CO2 prices and carbon capture investments

    International Nuclear Information System (INIS)

    We assess the option to install a carbon capture and storage (CCS) unit in a coal-fired power plant operating in a carbon-constrained environment. We consider two sources of risk, namely the price of emission allowance and the price of the electricity output. First we analyse the performance of the EU market for CO2 emission allowances. Specifically, we focus on the contracts maturing in the Kyoto Protocol's first commitment period (2008 to 2012) and calibrate the underlying parameters of the allowance price process. Then we refer to the Spanish wholesale electricity market and calibrate the parameters of the electricity price process. We use a two-dimensional binomial lattice to derive the optimal investment rule. In particular, we obtain the trigger allowance prices above which it is optimal to install the capture unit immediately. We further analyse the effect of changes in several variables on these critical prices, among them allowance price volatility and a hypothetical government subsidy. We conclude that, at current permit prices, immediate installation does not seem justified from a financial point of view. This need not be the case, though, if carbon market parameters change dramatically, carbon capture technology undergoes significant improvements, and/or a specific governmental policy to promote these units is adopted. (author)

  2. Serpentinite Carbonation in the Pollino Massif (southern Italy) for CO2 Sequestration

    Science.gov (United States)

    Carmela Dichicco, Maria; Mongelli, Giovanni; Paternoster, Michele; Rizzo, Giovanna

    2015-04-01

    and medium to high-grade metamorphic rocks. Primary mantle minerals are olivine, clinopyroxene, orthopyroxene, and spinel whereas serpentine, magnetite, chlorite, and amphibole are pseudomorphic minerals. Olivine is replaced by serpentine forming a mesh texture and orthopyroxene is mostly altered to bastite. Water chemistry indicates serpentinites interact with meteoric water producing a Mg-HCO3 type water in a system open to CO2. Brown Jr., G.E., Calas, G., (2011) - Environmental mineralogy - understanding element behavior in ecosystems. Comptes Rendus Geoscience 343, 90-112. Huijgen W.JJ., and Comans R.N.J., (2003) - Carbon dioxide sequestrationby mineral carbonation. Report Number ECN-C-03-016, Energy research Centre of the Netherlands (ECN), Petten, the Netherlands. Keller PJ, Schmidt AD, Wittbrodt J, Stelzer EHK. (2008) - Reconstruction of zebrafish early embryonic development by scanned light sheet microscopy. Science 322: 1065-1069. Margiotta, S., Mongelli, G., Summa, V., Paternoster, M., Fiore S. (2012) - Trace element distribution and Cr(VI) speciation in Ca-HCO3 and Mg-HCO3 spring waters from the northern sector of the Pollino massif, southern Italy. Journal of Geochemical Exploration. Power I.M., Wilson S.A., Dipple G.M. (2013) - Serpentinite Carbonation for CO2 Sequestration. Elements, 9, 115-121. Sansone M.T.C., Prosser G., Rizzo G., Tartarotti P. (2012) - Spinel-peridotites of the Frido Unit ophiolites: evidence for oceanic evolution. Periodico di Mineralogia. 81, 35-59. 10.2451/2012PM0003

  3. Post-combustion CO2 capture with a commercial activated carbon: Comparison of different regeneration strategies

    OpenAIRE

    González Plaza, Marta; García López, Susana; Rubiera González, Fernando; Pis Martínez, José Juan; Pevida García, Covadonga

    2010-01-01

    A commercial activated carbon supplied by Norit, R2030CO2, was evaluated as CO2 adsorbent under conditions relevant to post-combustion CO2 capture (ambient pressure and diluted CO2). It has been demonstrated that this carbon possesses sufficient CO2/N2 selectivity in order to efficiently separate a binary mixture composed of 17% CO2 in N2. Moreover, this carbon was easily completely regenerated and it did not show capacity decay after 10 consecutive cycles. Three different regeneration strate...

  4. Potential impact of DOC accumulation on fCO2 and carbonate ion computations in ocean acidification experiments

    Directory of Open Access Journals (Sweden)

    A. Oschlies

    2011-04-01

    Full Text Available The internal consistency of measurements and computations of components of the CO2-system, namely total alkalinity (AT, total dissolved carbon dioxide (CT, CO2 fugacity (fCO2, and pH, has been confirmed repeatedly in open ocean studies when the CO2 system had been over determined. Differences between measured and computed properties, such as ΔfCO2 (=fCO2(measured – fCO2(computed from AT and CT/ fCO2(measured× 100, there are usually below 5%. Recently, Hoppe et al. (2010 provided evidence of significantly larger ΔfCO2 in experimental setups. These observations are currently not well understood. Here we discuss a case from a series of phytoplankton culture experiments with ΔfCO2 of up to about 25%. ΔfCO2 varied systematically during the course of these experiments and showed a clear correlation with the accumulation of dissolved organic carbon (DOC. Culture and mesocosm experiments are often carried out under very high initial nutrient concentrations, yielding high biomass concentrations that in turn often lead to a substantial build-up of DOC. DOC can reach concentrations much higher than typically observed in the open ocean. To the extent that DOC includes organic acids and bases, it will contribute to the alkalinity of the seawater contained in the experimental device. Our analysis suggests that whenever substantial amounts of DOC are produced during the experiment, standard computer programs used to compute CO2 fugacity can underestimate true fCO2 significantly when the computation is based on AT and CT. Alternative explanations for large ΔfCO2, e.g. uncertainties of pKs, are explored as well, but are found to be of minor importance. Unless the effect of DOC-alkalinity is accounted for, this might lead to significant errors in the interpretation of the system under consideration to the experimentally applied CO2 perturbation, which could misguide the development of parameterisations used in simulations with global carbon cycle models

  5. Carbon dioxide sequestration by mineral carbonation. Literature Review

    International Nuclear Information System (INIS)

    In order to prevent CO2 concentrations in the atmosphere rising to unacceptable levels, carbon dioxide can be separated from the flue gas of, for example, a power plant and subsequently sequestrated. Various technologies for carbon dioxide sequestration have been proposed, such as storage in depleted gas fields, oceans and aquifers. An alternative sequestration route is the so-called 'mineral CO2 sequestration' route in which CO2 is chemically stored in solid carbonates by the carbonation of minerals. As mineral feedstock, rocks that are rich in alkaline earth silicates can be used. Examples are olivine (MgSiO4) and wollastonite (CaSiO3). Mineral CO2 sequestration has some fundamental advantages compared to other sequestration routes. The formed products are thermodynamically stable and therefore the sequestration of CO2 is permanent and safe. Furthermore, the sequestration capacity is large because large suitable feedstock deposits are available worldwide. Finally, the carbonation reactions are exothermic and occur spontaneously in nature. The reaction rates of the process at atmospheric conditions, however, are much too slow for an industrial process. Therefore, research focuses on increasing the reaction rate in order to obtain an industrial viable process. Optimisation of the process conditions is constrained by the thermodynamics of the process. Increasing the temperature and CO2 pressure accelerates the reaction rate, but gaseous CO2 is favoured over mineral carbonates at high temperatures. Using water or another solvent to extract the reactive component from the matrix accelerates the process. Pre-treatment of the mineral by size reduction and thermal or mechanical activation and optimisation of the solution chemistry result in major improvements of the reaction rate. During recent years, laboratory-scale experiments have shown major improvements of the conversion rates by developing various process routes and optimising process conditions. The most

  6. 太阳能技术对我国未来减排CO2的贡献%Contribution of solar energy technology to reduction of carbon dioxide in china

    Institute of Scientific and Technical Information of China (English)

    赵玉文

    2003-01-01

    @@ 1世界对可再生能源减排作用的估计 可再生能源不但是重要的后续能源,而且对未来减排CO2将发挥重要作用.国际上许多组织和国家预测,本世纪中叶可再生能源在一次性能源消耗中将超过50%.最近20年来,各种可再生能源技术的日趋成熟和生产规模的不断扩大,对能源的贡献也日渐增大.可以预料,随着可再生能源的快速发展,对未来CO2减排的贡献会越来越大.

  7. Carbon dioxide uptake by a temperate tidal sea

    NARCIS (Netherlands)

    Klaassen, Wim

    2007-01-01

    Carbon dioxide (CO2) exchange between the atmosphere and the Wadden Sea, a shallow coastal region along the northern Netherlands, has been measured from April 2006 onwards on a tidal flat and over open water. Tidal flat measurements were done using a flux chamber, and ship borne measurements using a

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

    International Nuclear Information System (INIS)

    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 CO2 emissions in six sectors among 28 provinces in China. • Examine the convergence of CO2 emissions in six sectors. • Investigate factors impact on convergence of CO2 emissions in each sector. • Factors impact on convergence of per capita CO2 emissions in each sector vary

  9. 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 of...

  10. Drivers of seasonality in Arctic carbon dioxide fluxes

    DEFF Research Database (Denmark)

    Mbufong, Herbert Njuabe

    perturbations and the potential for widespread feedbacks with global consequences. In this thesis, I present and discuss the findings of an investigation of comparable drivers of the seasonality in carbon dioxide (CO2) fluxes across heterogeneous Arctic tundra ecosystems. Due to the remoteness and the harsh...

  11. 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...

  12. Supercritical carbon dioxide process for pasteurization of fruit juices

    Science.gov (United States)

    Supercritical carbon dioxide (SCCO2) nonthermal processing inactivates microorganisms in juices using non-toxic and non-reactive CO2. However, data is lacking on the inactivation of E. coli K12 and L. plantarum in apple cider using pilot plant scale SCCO2 equipment. For this study, pasteurized pres...

  13. Carbon dioxide digital subtraction angiography manifestations of hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    LU Wei; LI Yan-hao; HE Xiao-feng; CHEN Yong; ZENG Qing-le; XU Xiao-li

    2002-01-01

    Objective: To investigate the imaging features and clinical significance of carbon dioxide digital subtraction angiography (CO2-DSA) in the diagnosis and treatment of hepatocellular carcinoma (HCC).Methods: Both CO2-DSA and conventional DSA were performed in all 47 patients with HCC, and the angiographic manifestations of CO2-DSA were compared with those of conventional DSA in the same patients.Results: Peripheral arterial and capillary imaging by CO2-DSA was inferior to that by conventional DSA, although blood pools were well visualized with CO2. Improved visualization of arterioportal shunting (APS)was obtained with CO2-DSA compared with that by conventional angiography. APS was observed in 33 cases by CO2-DSA and in 12 cases by conventional angiography (P<0. 001). Retrograde visualization of the portal vein (PV) trunk and its large branches was demonstrated in 16 cases by CO2-DSA and in 1 case by conventional DSA (P<0. 001). The manifestation of lipiodol retention in the tumors was consistent with CO2-DSA images after TAE in 38 cases, and with those of conventional DSA in 23 cases (P<0. 01). Conclusion: CO2-DSA was superior to conventional DSA in the detection of APS and retrograde visualization of PV system,and the former can provide usefulness information for the treatment planning (chemoembolization) and patient prognosis. Demonstration of APS by CO2-DSA may suggest the presence of intrahepatic metastases.

  14. Hydrologic support of carbon dioxide flux revealed by whole-lake carbon budgets

    Science.gov (United States)

    Stets, E.G.; Striegl, R.G.; Aiken, G.R.; Rosenberry, D.O.; Winter, T.C.

    2009-01-01

    Freshwater lakes are an important component of the global carbon cycle through both organic carbon (OC) sequestration and carbon dioxide (CO 2) emission. Most lakes have a net annual loss of CO2 to the atmosphere and substantial current evidence suggests that biologic mineralization of allochthonous OC maintains this flux. Because net CO 2 flux to the atmosphere implies net mineralization of OC within the lake ecosystem, it is also commonly assumed that net annual CO2 emission indicates negative net ecosystem production (NEP). We explored the relationship between atmospheric CO2 emission and NEP in two lakes known to have contrasting hydrologie characteristics and net CO2 emission. We calculated NEP for calendar year 2004 using whole-lake OC and inorganic carbon (IC) budgets, NEPoc and NEPIC, respectively, and compared the resulting values to measured annual CO 2 flux from the lakes. In both lakes, NEPIc and NEP Ic were positive, indicating net autotrophy. Therefore CO2 emission from these lakes was apparently not supported by mineralization of allochthonous organic material. In both lakes, hydrologie CO2 inputs, as well as CO2 evolved from netcalcite precipitation, could account for the net CO2 emission. NEP calculated from diel CO2 measurements was also affected by hydrologie inputs of CO2. These results indicate that CO2 emission and positive NEP may coincide in lakes, especially in carbonate terrain, and that all potential geologic, biogeochemical, and hydrologie sources of CO2 need to be accounted for when using CO2 concentrations to infer lake NEP. Copyright 2009 by the American Geophysical Union.

  15. 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.

  16. Production of precipitated calcium carbonate (PCC) from steelmaking slag for fixation of CO2

    International Nuclear Information System (INIS)

    Highlights: ► Ca extraction efficiency. ► Grain size and solid to liquid ratio. ► Production of PCC. - Abstract: Producing precipitated calcium carbonate (PCC) from steelmaking slag is a technology that contributes to the reduction of carbon dioxide emissions from iron and steel industries. While the carbon dioxide emissions from the sector are large, it could benefit from this option by utilizing its own by-products, i.e. steelmaking slags for fixation of CO2. Since the calcium content of the steelmaking slag is high, a calcium carbonate precipitate can be produced with the method which we have recently developed, and, if fulfilling the requirements (e.g. purity and crystal shape), it can be utilized as PCC. Therefore, the objective of this study is to further evaluate the feasibility of this method. Calcium was extracted selectively from the slag with aqueous solution of ammonium salt (NH4NO3, CH3COONH4 or NH4Cl) in an extraction reactor. After removal of the residual slag, the calcium-rich solution reacted with CO2 in a carbonation reactor producing PCC. Based on the experimental results, the slag’s grain size has a clear effect on the calcium extraction efficiency; the smaller the steel converter slag’s grain size, the larger the surface area, and the better the mass transfer rate which in turn results in a higher extraction efficiency. Grinding to smaller sizes is therefore one strategy towards improved efficiencies and chemical conversion rates. Solid to liquid ratio is another important parameter for improving extraction efficiency. The smallest solid to liquid ratio 5 g/l resulted in the maximum calcium extraction efficiency (73%) while the highest solid to liquid ratio 100 g/l resulted in the lowest extraction efficiency (6%). Consequently this option will be operationally expensive because of larger reactor volumes. The PCC produced from the calcium rich solution is comparable to the PCC produced with conventional methods

  17. Fluid phase equilibria during propylene carbonate synthesis from propylene oxide in carbon dioxide medium

    DEFF Research Database (Denmark)

    Gharnati, Loubna; Musko, Nikolai; Jensen, Anker Degn;

    2013-01-01

    In the present study the influence of the amount of carbon dioxide on the catalytic performance during the propylene carbonate synthesis from propylene oxide and CO2 was investigated. The reaction was performed in high-pressure batch autoclaves using immobilized 1-hydroxyethyl-9-propyl......-phase region where a CO2-expanded reactant/product phase (larger volume due to the dissolution of carbon dioxide in the liquid phase) is present. Optimal conditions for performing the reaction have been derived which requires consideration not only of the phase behavior of the starting phase but also of the...

  18. Multi-walled carbon nanotubes as catalyst promoter for dimethyl ether synthesis from CO2 hydrogenation

    International Nuclear Information System (INIS)

    The mixed acid of H2SO4/HNO3-pretreated multi-walled carbon nanotubes was employed as supports and ultrasound-assisted co-precipitation method was designed to prepare multi-walled carbon nanotubes supported CuO–ZnO–Al2O3/HZSM-5 catalyst. The catalyst was characterized by means of X-ray diffraction spectrum (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), thermal analysis (TG) and Brunauer–Emmett–Teller (BET). The catalyst activity for the preparation of dimethyl ether from hydrogenation of CO2 was investigated in a fixed-bed reactor, which showed that multi-walled carbon nanotubes could promote the catalyst activity of CuO–ZnO–Al2O3/HZSM-5. Under the reaction conditions of temperature at 262 °C, pressure at 3.0 MPa, H2/CO2 = 3 (volume ratio) and space velocity (SV) = 1800 mL gcat−1 h−1, the conversion per pass of carbon dioxide was 46.2%, with the dimethyl ether yield and selectivity of 20.9% and 45.2%.

  19. Dissolved CO2 in small catchment streams of eastern Amazonia: A minor pathway of terrestrial carbon loss

    Science.gov (United States)

    Davidson, Eric A.; Figueiredo, Ricardo O.; Markewitz, Daniel; Aufdenkampe, Anthony K.

    2010-12-01

    Production of carbon dioxide (CO2) in soils can lead to supersaturation of dissolved free CO2 (pCO2) in groundwater, which later evades to the atmosphere as groundwater enters streams and rivers. This process could be a significant pathway for return of terrestrially fixed C to the atmosphere. We measured pCO2 monthly over two years at multiple stations along three streams from their headwaters in remnant mature forests through multiple land covers in Pará, Brazil. The pCO2 averaged 19,000 μatm in headwaters and decreased to about 4,500 μatm downstream. Similar values were measured in headwaters of two small pristine mature forest catchments. Two approaches were used to estimate groundwater pCO2 evasion: assuming that headwater pCO2 measurements reflected incoming groundwater pCO2 or that all entering stream water was in equilibrium with previously measured deep soil CO2. With these assumptions, losses from the terrestrial environment through aquatic evasion of pCO2 would be 0.02-0.15 Mg C ha-1 of land area yr-1, which is about 2-3 orders of magnitude lower than annual estimates of soil respiration and net primary productivity. However, downstream pCO2 values that appear to be in quasi-steady state indicate contributions from other C sources, such as aquatic primary production, soil erosion, dissolved organic matter, or litter inputs from streamside vegetation. Hence, lateral pCO2 loss from groundwater to streams is minor for most of the terrestrial ecosystems of this region, although C loss to streams could be significant for net terrestrial budgets in riparian ecosystems or areas experiencing erosion.

  20. Extraction of Rosemary Oil by Supercritical Carbon Dioxide Fluid and Activity Component of the Extract%超临界CO2流体萃取法提取迷迭香中主要挥发性成分研究

    Institute of Scientific and Technical Information of China (English)

    黎乃维; 马丽杰; 金海珠

    2014-01-01

    Essential oil was extracted from the stems and leaves of the plant produced in Yunnan by Supercritical Carbon Dioxide Fluid Extraction. With the single-factor and orthogonal design, to determine the optimal conditions test. Experimental results show that the optimal conditions as follow:Extraction temperature 40℃, Pressure 20 MPa, Time 120 min, CO2 Flow 25 L/h. The activity components of the essential oil were analyzed by GC-MS. From the Experimental date, we can see Essential oil composition is complex and diverse. Mixed aroma of high contents, such as Camphor (25%),Eucalyptol (32%),Ammonium acetat e (9%),beta.-Pinene (4%), make up the featured aroma of Rosemary.%以云南迷迭香为原料,利用超临界CO2流体萃取装置提取迷迭香精油,然后采用GC-MS联用分析仪对所得的萃取物进行分析。通过单因素和正交试验优化萃取条件,实验结果表明萃取温度40℃、萃取压力20 MPa、萃取时间120 min、CO2流量25 L/h为最优萃取条件。通过GC-MS联用进行活性成分分析,所得迷迭香精油主要是樟脑(25%),桉叶油素(32%),乙酸铵(9%), beta.-蒎烯(4%)等混合香气构成了迷迭香的特征香气。

  1. Application of carbon isotope for discriminating sources of soil CO2 in karst area, Guizhou

    Institute of Scientific and Technical Information of China (English)

    黎廷宇; 王世杰

    2001-01-01

    Using carbon isotope of soil CO2 this paper discussed the sources of soil CO2 in karst area, Guizhou Province, China. Oxidation-decomposition of organic matter, respiration of plant root and activity of microbe are thought to be the major sources of soil CO2. However, in karst area, the contribution of dissolution of underlying carbonate rock to soil CO2 should be considered as in acidic environment. Atmospheric CO2 is the major composition of soil CO2 in surface layer of soil profiles and its proportion in soil CO2 decreases with increase of soil depth. CO2 produced by dissolution of carbonate rock contributes 34%-46% to soil CO2 below the depth of 10cm in the studied soil profiles covered by grass.

  2. Nanostructured Graphene-Titanium Dioxide Composites Synthesized by a Single-Step Aerosol Process for Photoreduction of Carbon Dioxide

    OpenAIRE

    Wang, Wei-Ning; Jiang, Yi; Fortner, John D.; Biswas, Pratim

    2014-01-01

    Photocatalytic reduction of carbon dioxide (CO2) to hydrocarbons by using nanostructured materials activated by solar energy is a promising approach to recycling CO2 as a fuel feedstock. CO2 photoreduction, however, suffers from low efficiency mainly due to the inherent drawback of fast electron-hole recombination in photocatalysts. This work reports the synthesis of nanostructured composites of titania (TiO2) nanoparticles (NPs) encapsulated by reduced graphene oxide (rGO) nanosheets via an ...

  3. Intravenous carbon dioxide as an echocardiographic contrast agent

    OpenAIRE

    Meltzer, Richard; Serruys, Patrick; Hugenholtz, Paul; 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 patients contrast density from 5% dextrose was compared with that from 5% dextrose-CO2 injections. Six of these patients had no contrast on the initial 5% dextrose injection and definite contrast with the...

  4. The Manufacture of Polymer Nanocomposite Materials Using Supercritical Carbon Dioxide

    OpenAIRE

    Chen, Chen

    2011-01-01

    The use of supercritical carbon dioxide (scCO2) as a processing aid to help exfoliate nano-clays and improve their dispersion during melt blending in polymer matrices has been reported in the literature. One of the best processes in terms of improving the degree of nano-clay dispersion and composite mechanical properties was developed in our laboratory. This process allows the clay to be in direct contact with scCO2 and expanding the clay-CO2 mixture via rapid depressurization into a two-stag...

  5. Highly precise atmospheric oxygen measurements as a tool to detect leaks of carbon dioxide from Carbon Capture and Storage sites

    NARCIS (Netherlands)

    van Leeuwen, Charlotte

    2015-01-01

    In Carbon Capture and Storage (CCS), carbon dioxide (CO2) from fossil fuel combustion is stored underground into a geological formation. Although the storage of CO2 is considered as safe, leakage to the atmosphere is an important concern and monitoring is necessary. Detecting and quantifying leaks o

  6. CO2 capture by biomimetic adsorption: enzyme mediated co2 absorption for post-combustion carbon sequestration and storage process

    NARCIS (Netherlands)

    Russo, M.E.; Olivieri, G.; Salatino, P.; Marzocchella, A.

    2013-01-01

    The huge emission of greenhouse gases from fossil-fuelled power plants is emphasizing the need for efficient Carbon Capture and Storage (CCS) technologies. The biomimetic CO2 absorption in aqueous solutions has been recently investigated as a promising innovative alternative for post-combustion CCS.

  7. Carbon-14 measurement using carbon dioxide absorption method - Our experience

    International Nuclear Information System (INIS)

    Carbon-C14 measurement using absorption technique consists of direct absorption of sample carbon dioxide into an absorber - scintillator mixture. This technique is a simple, fast, less expensive and less hazardous technique compared to benzene synthesis or any other technique. This techniques enable us in preparing six/seven samples in a day while benzene synthesis technique takes two days for the preparation of one sample. It is useful for radiocarbon age up to about 38,000 a BP (∼1 pMC), which is adequate for most of the hydrological investigations. All the total dissolved inorganic carbon (TDIC) is precipitated as barium carbonate from the ∼60 to 70 liters of water at the site. In the laboratory, it is reacted with orthophosphoric acid to give carbon dioxide (CO2). This carbon dioxide is transferred into 0.5 L capacity cylinder. The reaction and collection of gas is done under vacuum using a glass vacuum line. Carbon dioxide is directly absorbed in 11.5 ml of carbasorb + 11 ml of Permaflour V (commercially not available) or its equivalent scintillator in the specially made absorption apparatus. Since, absorption process is exothermic, temperature of the medium is maintained at about 220 deg. C, it results in the absorption of ∼7 m moles of carbon dioxide per mL of cabasorb. As reaction progresses, bubbles can be seen rising slowly. The end point is marked by rapid rise in the solution level. Carbon dioxide obtained from oxalic acid (Standard) and background carbon dioxide are also absorbed in the same quantity of absorber and scintillator mixture. Samples, standard and background are transferred in 22 mL teflon vials and counted in low level liquid scintillation counter (LKB Wallac 1220 Quantulus) for 1000 minutes. The counting efficiency at best factor of merit (AON/ON/√B) is ∼60 % where AON is normalized net count rate of standard and B is the background count rate. The mean count rate of last fifteen background samples is 0.64 ± .0005 cpm with an

  8. Crescimento e índices de troca gasosa em plantas de pepino irrigadas com água enriquecida com CO2 Growth analysis and gaseous exchange in cucumber plants irrigated with carbon dioxide enriched water

    Directory of Open Access Journals (Sweden)

    Kathia A.L. Canizares

    2004-12-01

    Full Text Available Avaliou-se o efeito do enriquecimento da água de irrigação com CO2 sobre índices fisiológicos de desenvolvimento e troca gasosa de folhas de plantas de pepino do tipo japonês, cultivados em ambiente protegido. Os experimentos realizados em duas épocas do ano foram instalados em delineamento experimental de blocos ao acaso com 4 tratamentos e 5 repetições. Os tratamentos foram constituídos pelos híbridos Hokuho e Tsuyataro, irrigados com água comum ou enriquecida com CO2, em uma concentração de 1‰ no primeiro e 0,25‰ no segundo experimento. A produção de massa de material seco e área foliar adotaram tendência exponencial, não sendo possível observar o início da diminuição da taxa de produção de massa do material seco aos 63 dias após transplante (DAT. A taxa de crescimento da comunidade e taxa de crescimento relativa do híbrido Hokuho irrigado com água comum foi diferente do irrigado com água enriquecida com CO2, no entanto, no híbrido Tsuyataro foram semelhantes. A taxa de assimilação líquida atingiu a máxima pendente na fase de crescimento vegetativo e floração, e foi reduzida drasticamente após os 20 DAT no híbrido Hokuho, e após os 35 DAT no híbrido Tsuyataro. A razão de área foliar diminuiu ligeiramente nos dois híbridos com o desenvolvimento do cultivo. No início observaram-se diferenças entre irrigação com água comum e enriquecida com CO2, porém após 20 DAT não se apreciaram mais diferenças. Quanto a troca gasosa, a taxa assimilatória líquida de CO2 e de transpiração, conductância estomática e eficiência no uso da água foram semelhantes entre plantas irrigadas com água comum e enriquecida com CO2 durante o primeiro semestre. Já no segundo semestre, maiores valores foram registrados pelas plantas irrigadas com água enriquecida.Experiments under protected cultivation, in two sowing dates, were set up to evaluate the effect of irrigation water enriched or not with CO2, on

  9. SIMULATION OF CARBON DIOXIDE EMISSIONS FROM DAIRY FARMS TO ASSESS GREENHOUSE GAS REDUCTION STRATEGIES

    Science.gov (United States)

    Farming practices can have a large impact on the soil carbon cycle and the resulting net emission of greenhouse gases including carbon dioxide (CO**2), methane and nitrous oxide. Primary sources of CO**2 emission on dairy farms are soil, plant, and animal respiration with smaller contributions from ...

  10. One strategy for estimating the potential soil carbon storage due to CO2 fertilization

    International Nuclear Information System (INIS)

    Soil radiocarbon measurements can be used to estimate soil carbon turnover rates and inventories. A labile component of soil carbon has the potential to respond to perturbations such as CO2 fertilization, changing climate, and changing land use. Soil carbon has influenced past and present atmospheric CO2 levels and will influence future levels. A model is used to calculate the amount of additional carbon stored in soil because of CO2 fertilization

  11. 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

    2014-01-01

    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.

  12. Carbon Dioxide - Our Common "Enemy"

    Science.gov (United States)

    James, John T.; Macatangay, Ariel

    2009-01-01

    Health effects of brief and prolonged exposure to carbon dioxide continue to be a concern for those of us who manage this pollutant in closed volumes, such as in spacecraft and submarines. In both examples, considerable resources are required to scrub the atmosphere to levels that are considered totally safe for maintenance of crew health and performance. Defining safe levels is not a simple task because of many confounding factors, including: lack of a robust database on human exposures, suspected significant variations in individual susceptibility, variations in the endpoints used to assess potentially adverse effects, the added effects of stress, and the fluid shifts associated with micro-gravity (astronauts only). In 2007 the National Research Council proposed revised Continuous Exposure Guidelines (CEGLs) and Emergency Exposure Guidelines (EEGLs) to the U.S. Navy. Similarly, in 2008 the NASA Toxicology Group, in cooperation with another subcommittee of the National Research Council, revised Spacecraft Maximum Allowable Concentrations (SMACs). In addition, a 1000-day exposure limit was set for long-duration spaceflights to celestial bodies. Herein we examine the rationale for the levels proposed to the U.S. Navy and compare this rationale with the one used by NASA to set its limits. We include a critical review of previous studies on the effects of exposure to carbon dioxide and attempt to dissect out the challenges associated with setting fully-defensible limits. We also describe recent experiences with management of carbon dioxide aboard the International Space Station with 13 persons aboard. This includes the tandem operations of the Russian Vozduk and the U.S. Carbon Dioxide Removal System. A third removal system is present while the station is docked to the Shuttle spacecraft, so our experience includes the lithium hydroxide system aboard Shuttle for the removal of carbon dioxide. We discuss strategies for highly-efficient, regenerable removal of carbon

  13. CO2 sequestration using accelerated gas-solid carbonation of pre-treated EAF steel-making bag house dust.

    Science.gov (United States)

    El-Naas, Muftah H; El Gamal, Maisa; Hameedi, Suhaib; Mohamed, Abdel-Mohsen O

    2015-06-01

    Mineral CO2 sequestration is a promising process for the reduction of carbon dioxide emissions to the atmosphere. In this paper, alkaline calcium-rich dust particles collected from bag filters of electric arc furnaces (EAF) for steel making were utilized as a viable raw material for mineral CO2 sequestration. The dust particles were pre-treated through hydration, drying and screening. The pre-treated particles were then subjected to direct gas-solid carbonation reaction in a fluidized-bed reactor. The carbonated products were characterized to determine the overall sequestration capacity and the mineralogical structures. Leaching tests were also performed to measure the extracted minerals from the carbonated dust and evaluate the carbonation process on dust stabilization. The experimental results indicated that CO2 could be sequestered using the pre-treated bag house dust. The maximum sequestration of CO2 was 0.657 kg/kg of dust, based on the total calcium content. The highest degree of carbonation achieved was 42.5% and the carbonation efficiency was 69% at room temperature. PMID:25846002

  14. The underground storages of carbon dioxide. Juridical aspects

    International Nuclear Information System (INIS)

    In the framework of the reduction of the carbon dioxide emissions in the air, the underground storage of the CO2 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 CO2 underground storages and the first artificial storages are discussed. The CO2 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.)

  15. Carbon dioxide reduction in housing: experiences in urban renewal projects in the Netherlands

    OpenAIRE

    Waals, F.M. van der; Vermeulen, W.J.V.; Glasbergen, P.

    2003-01-01

    It is increasingly being recognised that the housing sector can contribute to reductions in the levels of carbon dioxide (CO 2 ). The renewal of existing residential areas offers opportunities to reduce CO 2 emissions. However, technical options for CO 2 -reduction, such as insulation, solar energy, and combined heat and power, often fail to materialise. For a better understanding of why options for CO 2 -reduction are applied or rejected, it is insufficient to consider only the economic and ...

  16. Measuring CO2 from Space: The NASA Orbiting Carbon Observatory-2

    Science.gov (United States)

    Crisp, D.

    2010-01-01

    The Orbiting Carbon Observatory (OCO) was the first NASA satellite designed to measure atmospheric carbon dioxide (CO2) from space with the precision, resolution, and coverage needed to detect CO2 surface fluxes. OCO was designed to collect 0.5 to 1 million soundings each day. Typical measurements over land were expected to have precisions of 0.3% within surface footprints smaller less than 3 square km. This project suffered a major setback in February 2009 when the OCO launch vehicle failed to achieve orbit and the satellite was lost. The U.S. Congress has since authorized a restart of the OCO project, and the President's 2010 budget proposal includes funding to develop and fly a replacement for OCO that could be ready for launch no later than February 2013. This mission has been designated OCO-2. While this mission will be a near "carbon copy" of OCO, some changes were needed to replace components that were no longer available. Here, we describe the capabilities, of the OCO-2 mission, highlighting its differences from OCO.

  17. EVALUATION OF SUPERCRITICAL CARBON DIOXIDE TECHNOLOGY TO REDUCE SOLVENT IN SPRAY COATING APPLICATIONS

    Science.gov (United States)

    This evaluation, part of the Pollution Prevention Clean Technology Demonstration (CTD) Program, addresses the product quality, waste reduction, and economic issues of spray paint application using supercritical carbon dioxide (CO2). Anion Carbide has developed this technology and...

  18. Bio-Electrochemical Carbon Dioxide Removal for Air Revitalization in Exploration Life Support Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — An important aspect of the ISS air revitalization system for life support is the removal of carbon dioxide from cabin air and retrieves oxygen from CO2. The current...

  19. Contribution of Soil Carbonates to CO2 Emissions Following Land Use Change

    Science.gov (United States)

    Grand, S.; Rothstein, D.

    2014-12-01

    Land disturbance is known to contribute to carbon dioxide emission through accelerated decomposition of soil organic matter. Many soils also contain large stocks of potentially reactive inorganic C (Ci) in the form of carbonate minerals. Under strong acidification conditions, as can be generated by nitrification and other biogeochemical reactions, carbonate weathering has the potential to generate CO2 emissions on a short time scale; yet little is known about the contribution of this process to disturbance-related C emissions. Information is particularly scarce for high-latitude alkaline soils. The objective of this study is to determine the contribution of Ci to total greenhouse gas emissions from soil following a land disturbance event. The perturbation consisted of the conversion of long-idled agricultural land to a woody bioenergy plantation. We hypothesized that this land use change would intensify acidification processes and increase the release of Ci. We tested this hypothesis by monitoring greenhouse gas emissions during the establishment of a poplar plantation on soils developed from limestone-derived glacial drift in northern Michigan, USA. We used 13C natural abundance to estimate the contribution of Ci to soil C emissions. We found that carbonates were abundant in the soil profile despite the leaching associated with the humid climate. Carbonate-C concentration averaged 2 g/kg in the topsoil and 15 to 25 g/kg in the deep subsoil. The persistence of measurable carbonate concentrations above the expected weathering front was likely due to biological translocation processes. Using a Bayesian isotopic mixing model accounting for endmember uncertainties, we detected a significant contribution of Ci to total soil CO2 emissions at the plot scale. There was a significant interaction between disturbance and season. In the spring, Ci emissions were three times higher in newly established poplar plots than in control plots. In the summer, Ci emissions in control

  20. Industrial structural transformation and carbon dioxide emissions in China

    International Nuclear Information System (INIS)

    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 CO2 emissions in China. ► Dynamic panel data model. ► Industrial structural adjustments can effectively reduce current CO2 emissions. ► Technical progress leads to decreasing CO2 emissions through upgrading of industrial structure

  1. Refrigeration plants using carbon dioxide as refrigerant: measuring and modelling the solubility and diffusion of carbon dioxide in polymers used as sealing materials

    DEFF Research Database (Denmark)

    von Solms, Nicolas; Kristensen, Jakob

    2010-01-01

    Because of increased environmental pressure, there is currently a movement away from more traditional refrigerants such as HCFC's toward refrigerants with lower global warming potential such as carbon dioxide (CO2). However, the use of CO2 as a refrigerant requires a refrigeration cycle with...

  2. Carbon analysis for inspecting carbonation of concrete using a TEA CO2 laser-induced plasma.

    Science.gov (United States)

    Kagawa, Kiichiro; Idris, Nasrullah; Wada, Munehide; Kurniawan, Hendrik; Tsuyuki, Kenichiro; Miura, Satoru

    2004-08-01

    It has been demonstrated that a spectrochemical analysis of carbon using the laser plasma method can be successfully applied to inspect the carbonation of concrete by detecting carbon produced in aged concrete by a chemical reaction of Ca(OH)2 with CO2 gas in environmental air, turning into CaCO3, which induces degradation of the quality of building concrete. A comparative study has been made using a TEA CO2 laser (500-1000 mJ) and a Q-switched Nd-YAG laser (50-200 mJ) to search for the optimum conditions for carbon analysis, proving the advantage of the TEA CO2 laser for this purpose. Also, it was clarified that laser irradiation with suitable defocusing conditions is a crucial point for obtaining high sensitivity in the detection of carbon. Practical experiments on the inspection of carbonation were carried out using both a concrete sample that had been intentionally carbonated by exposure to high concentrations of CO2 gas and a naturally carbonated concrete sample. As a result, good coincidence was observed between the laser method and the ordinary method, which uses the chemical indicator phenolphthalein, implying that this laser technique is applicable as an in situ quantitative method of inspection for carbonation of concrete. PMID:18070383

  3. Preparation of Hydrophobic Silica Membranes for Methane and Carbon Dioxide Separation%用于分离CH4/CO2疏水性SiO2膜的制备

    Institute of Scientific and Technical Information of China (English)

    李文秀; 葛珂宁; 张兵; 陈立峰; 张志刚

    2013-01-01

    分别采用KH-570,KH-560和A-151代替部分TEOS作为前驱体,通过溶胶-凝胶法制备了疏水性SiO2气体分离膜,利用IR,BET,TG,SEM以及接触角测试仪等对其进行了表征,并对(0.8KH-570)SiO2膜进行了CH4/CO2气体渗透性能评价.结果表明,当A-151,KH-570和KH-560与TEOS的摩尔比均为0.8时,膜的接触角分别从28.6°增大到97.8,94.2°和90.7°.膜样品的疏水性增强,修饰后的膜孔径分布更加狭窄,平均孔径减小,抵抗水蒸汽的能力明显增强;膜层无开裂,表面完整.其中,KH-570修饰的膜性能较好,在n(KH-570)/n(TEOS)=0.8时,压力为30kPa的条件下,(0.8KH-570)SiO2膜对CH4/CO2的分离因子为2.13,大于纯SiO2膜的分离因子(1.58)和努森扩散理论的分离因子(1.67),分离效果较好.%Hydrophobic silica gas separation membranes were prepared by acid catalysed co-hydrolysis and condensation reaction of tetraethylorthosilicate (TEOS) and γ-methacryloxypropyltrimethoxy-silane(KH-570) or γ-glycidyltrimethoxysilane(KH-560) or vinyl triethoxysilane in ethanol,characterized by IR,BET,TG-DTG , SEM, the measurement of contact angle,and (0. 8KH-570) silica membranes were evaluated by CH4/CO2 gas permeability. The results showed that,as the molar ratio of A-151/TEOS, KH-570/TEOS and KH-560/TEOS increased to 0. 8, it was found that the water contact angle were respectively 97. 8,94. 2°and 90. 7°, and the unmodified membrane was only 28. 6°. The hy-drophobicity of modified membrane samples enhanced. Modified silica membranes had a desirable pore structure,pore size distribution was more narrow and pore width gradually reduced. In the moisture environment , modified silica membranes could be better for resisting water vapor than the unmodified silica membranes. Modified silica membranes were basically free crack, and the surfaces were integrated. Modified silica membrane by KH-570 was best. For the modified silica membranes with KH-570/ TEOS molar ratio of 0. 8,CH4/CO2 separation

  4. Review on Capture and Utilization Technology of Carbon Dioxide in Coal-fired Power Plant%燃煤电厂CO2捕集与利用技术综述

    Institute of Scientific and Technical Information of China (English)

    纪龙; 曾鸣

    2014-01-01

    随着全球气候变暖的不断加剧,C02排放控制技术正受到越来越多的关注.文章全面介绍了近期国内外适用于燃煤电厂的二氧化碳捕集与利用技术的研究进展,对以氨水作为吸收剂的化学吸收法、CO2碳化利用技术、CO2捕集与矿化利用一体化技术做了重点介绍和客观评价.其中,氨水、法相比其他吸收工艺具有更高的吸收能力,较快的反应速度,不产生腐蚀问题,且能耗和价格较低;碳化利用技术因可用矿物资源储量大、分布广,受地域限制较小而表现出巨大的发展潜力;C02捕集与矿化利用一体化的新工艺,被证明能够克服传统工艺高能耗、低效率的缺点,同时还能生产有较高附加值的副产品来降低成本,有着良好的发展前景.

  5. Carbon dioxide storage capacity in gas shale reservoirs

    International Nuclear Information System (INIS)

    As the commercial success of shale gas exploitation in USA, there also amount of water resource depleted and some potential environmental problems exist. According to the low pore pressure, low porosity, low permeability characteristic of shale gas reservoir, and the successful experience of CO2 sequestration and enhanced methane recovery in the unminable coalbed, incorporating the differential adsorption capacity of CO2 and CH4 in shale, the injection technology of CO2 into shale gas reservoir for storage and enhancing shale gas recovery was pro- posed. Then the technology, economic and safety feasibility of this solution was analyzed. The result suggested that the shales adsorb more carbon dioxide than methane at reservoir conditions, the methane can be displaced by carbon dioxide injection and enhanced shale gas recovery could be achieved. A model for calculation of CO2 storage capacity was development, the preliminary estimate of the CO2 storage potential was 2.11∼4.32 times of the shale gas. So Injection of carbon di- oxide into shale gas reservoir is a promising technology which has the potential to enhance shale gas recovery, while simultaneously sequestering amount of CO2. (authors)

  6. Carbon dioxide removal from coal-fired power plants

    International Nuclear Information System (INIS)

    To diminish the threat of a rapidly changing climate, emissions of CO2 should be reduced. One way to reduce these emissions is CO2 removal -the recovery of carbon dioxide from energy conversion processes and storage outside the atmosphere. This book gives an extensive description of three methods of capturing CO2 from flue gases of a conventional coal-fired power plant using amines, polymer membranes; and low temperature distillation, and two methods that are based on the modification of an integrated coal gasifier combined cycle plant, one using a shift reactor and a scrubber, the other using membrane separation and a CO2 gas turbine. The present state of the technology is described and optimized recovery designs are presented. Energy use is calculated in detail and elaborate cost calculations are given. In the last chapter, global storage potentials and costs of CO2 in aquifers, empty natural gas, and oil fields, are discussed. 170 refs

  7. Transcutaneous carbon dioxide during sleep-disordered breathing.

    Science.gov (United States)

    Rimpilä, Ville; Hosokawa, Keisuke; Huhtala, Heini; Saaresranta, Tarja; Salminen, Aaro V; Polo, Olli

    2015-12-01

    Respiratory drive is tightly controlled by the carbon dioxide levels. We tested the hypothesis that sequences of sleep apnoea (obstructive, central or mixed), hypopnoea and flow limitation are characterized by different levels of transcutaneous CO2 (PtcCO2). Polygraphic recordings (n=555) from patients with suspected sleep-disordered breathing (SDB) were retrospectively screened to find sequences (5 min or 10 events) of both SDB and steady breathing. Eighty-eight SDB sequences from 44 patients were included and PtcCO2 and SpO2 values were collected. PtcCO2 values during sequences were normalized by setting wakefulness level as 100%. In terms of PtcCO2, apnoea sequences with central component (central (n=7) and mixed (n=3) apnoea) did not differ from wakefulness (102.0% vs 100%, p=0.122) whereas obstructive apnoea (105.8%, pmonitoring during sleep adds to the understanding of different SDB phenotypes. PMID:26474829

  8. 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.

  9. Carbonic anhydrase mediated carbon dioxide sequestration: promises, challenges and future prospects.

    Science.gov (United States)

    Yadav, Raju R; Krishnamurthi, Kannan; Mudliar, Sandeep N; Devi, S Saravana; Naoghare, Pravin K; Bafana, Amit; Chakrabarti, Tapan

    2014-06-01

    Anthropogenic activities have substantially increased the level of greenhouse gases (GHGs) in the atmosphere and are contributing significantly to the global warming. Carbon dioxide (CO2 ) is one of the major GHGs which plays a key role in the climate change. Various approaches and methodologies are under investigation to address CO2 capture and sequestration worldwide. Carbonic anhydrase (CA) mediated CO2 sequestration is one of the promising options. Therefore, the present review elaborates recent developments in CA, its immobilization and bioreactor methodologies towards CO2 sequestration using the CA enzyme. The promises and challenges associated with the efficient utilization of CA for CO2 sequestration and scale up from flask to lab-scale bioreactor are critically discussed. Finally, the current review also recommends the possible future needs and directions to utilize CA for CO2 sequestration. PMID:24740638

  10. Effects of the transcutaneous electrode temperature on the accuracy of transcutaneous carbon dioxide tension

    DEFF Research Database (Denmark)

    Sørensen, Line C; Brage-Andersen, Lene; Greisen, Gorm

    2011-01-01

    The harmful effect of hypocapnia on the neonatal brain emphasizes the importance of monitoring arterial carbon dioxide tension (PaCO2). Transcutaneous monitoring of carbon dioxide (tcPCO2) reduces the need for arterial blood sampling. Drawbacks are high electrode temperature causing risks of skin...

  11. Constraining terrestrial ecosystem CO2 fluxes by integrating models of biogeochemistry and atmospheric transport and data of surface carbon fluxes and atmospheric CO2 concentrations

    OpenAIRE

    Zhu, Q.; Zhuang, Q.; D. Henze; Bowman, K.; M. Chen; Liu, Y.; He, Y.; Matsueda, H.; Machida, T.; Sawa, Y.; W. Oechel

    2014-01-01

    Regional net carbon fluxes of terrestrial ecosystems could be estimated with either biogeochemistry models by assimilating surface carbon flux measurements or atmospheric CO2 inversions by assimilating observations of atmospheric CO2 concentrations. Here we combine the ecosystem biogeochemistry modeling and atmospheric CO2 inverse modeling to investigate the magnitude and spatial distribution of the terrestrial ecosystem CO2 sources and sinks. First, we constrain a terrestri...

  12. High capacity carbon dioxide sorbent

    Energy Technology Data Exchange (ETDEWEB)

    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.

  13. Partial pressure of carbon dioxide (pCO2), temperature, salinity and other variables collected from surface underway observations using shower head equilibrator, carbon dioxide gas detector, and other instruments from R/V Oscar Dyson in the Berling Sea and coast of Alaska from 2014-03-03 to 2014-08-13 (NCEI Accession 0132046)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This archival package contains underway measurements of pCO2, salinity, sea surface temperature, and other parameters collected in 2014 on board the NOAA Ship Oscar...

  14. Partial pressure of carbon dioxide (pCO2), temperature, salinity and other variables collected from surface underway observations using shower head equilibrator, carbon dioxide gas detector, and other instruments from container ship Cap Vilano in the Pacific Ocean from 2013-02-01 to 2013-06-06 (NCEI Accession 0132054)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This archival package contains underway measurements of pCO2, salinity, sea surface temperature, and other parameters were collected during 3 trans-Pacific...

  15. Partial pressure of carbon dioxide (pCO2), temperature, salinity and other variables collected from surface underway observations using shower head equilibrator, carbon dioxide gas detector, and other instruments from container ship Cap Blanche in the Pacific Ocean from 2014-02-01 to 2014-11-26 (NCEI Accession 0132047)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This archival package contains underway measurements of pCO2, salinity, sea surface temperature, and other parameters were collected during 6 trans-Pacific...

  16. Partial pressure of carbon dioxide (pCO2), temperature, salinity and other variables collected from surface underway observations using shower head equilibrator, carbon dioxide gas detector, and other instruments from 4 trans-Pacific crossings onboard container ship Cap Blanche in the Pacific Ocean from 2015-03-28 to 2015-12-04 (NCEI Accession 0141304)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Underway measurements of pCO2, salinity, sea surface temperature, and other parameters were collected during 4 trans-Pacific crossings in 2015 on the container ship...

  17. Carbon dioxide transport over complex terrain

    OpenAIRE

    Sun, RC

    2004-01-01

    The nocturnal transport of carbon dioxide over complex terrain was investigated. The high carbon dioxide under very stable conditions flows to local low-ground. The regional drainage flow dominates the carbon dioxide transport at the 6 m above the ground and carbon dioxide was transported to the regional low ground. The results show that the local drainage flow was sensitive to turbulent mixing associated with local wind shear.

  18. Perspectives in the use of carbon dioxide

    OpenAIRE

    1999-01-01

    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...

  19. Measurement of regional pulmonary function with carbon-11-labeled CO2 and CO

    International Nuclear Information System (INIS)

    Carbon dioxide and carbon monoxide labelled with carbon-11 have been produced in the remotecontrolled system for a large scale production of short lived radioactive substance with cyclotron in National Institute of Radiological Sciences. The single breath measurement with 11CO2 and 11CO, using inhalation system and a coincidence positron camera combined with an on-line computer system (TOSBAC 3400 Model 31) has been employed to evaluate regional pulmonary blood flow and diffusing capacity in three normal volunteers and seven patients with chronic obstructive pulmonary disease (COPD), old lung tuberculosis and benign tumor. Regional clearance rate constant (lambda) and distribution index (lambda i/lambda t) were calculated from monoexponential removal curves measured by external counting over the chest in supine position. This process was performed in a short period of breath-holding (10 - 20 sec.) after a single breath of these radioactive gases mixed with room air. These parameters were calculated for each lung fields divided into four zones (bilateral upper and lower lung region). In our method, the activity of the inspired mixture were 5 - 35 mCi/L and each value in lung fields, divided into four zones, can be measured with time interval for one second. While the clearance rate of 11CO2 seemed to be mainly limited by pulmonary blood flow, it was considered that the rate of 11CO were limited by not only the diffusing capacity but also the perfusion in each lung fields. In normal subjects, the distribution of regional clearance rate was showed approximately even for 11CO2 and 11CO. It was caused of the measurement in supine position. In contrast, the distribution of these parameter was showed uneven in patients with lung disease, particularly with COPD. (author)

  20. 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…

  1. Ocean uptake of carbon dioxide

    International Nuclear Information System (INIS)

    Factors controlling the capacity of the ocean for taking up anthropogenic C02 include carbon chemistry, distribution of alkalinity, pCO2 and total concentration of dissolved C02, sea-air pCO2 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 C02 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 C02 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 C02 fertilization is a potential candidate for such missing carbon sinks

  2. Carbon capture and biogas enhancement by carbon dioxide enrichment of anaerobic digesters treating sewage sludge or food waste

    OpenAIRE

    Bajón, Fernández Y; Soares, Ana; Villa, Raffaella; Vale, P; Cartmell, Elise

    2014-01-01

    The increasing concentration of carbon dioxide (CO2) in the atmosphere and the stringent greenhouse gases (GHG) reduction targets, require the development of CO2 sequestration technologies applicable for the waste and wastewater sector. This study addressed the reduction of CO2 emissions and enhancement of biogas production associated with CO2 enrichment of anaerobic digesters (ADs). The benefits of CO2 enrichment were examined by injecting CO2 at 0, 0.3, 0.6 and 0.9M fractions into batch ADs...

  3. Carbon and oxygen isotopes in apatite CO2 and co-existing calcite

    International Nuclear Information System (INIS)

    Carbon and oxygen isotopes were analyzed in carbonate apatite CO2 and in co-existing calcite. Both C and O in apatite CO2 are enriched in the respective light isotopes relative to calcite. These results confirm the proposition that carbonate is part of the apatite structure

  4. A Molecular Dynamics Study on the Confinement of Carbon Dioxide Molecules in Carbon Nanotubes

    Science.gov (United States)

    Lazor, Meagan; Rende, Deniz; Baysal, Nihat; Ozisik, Rahmi

    2012-02-01

    The influence of atmospheric carbon dioxide (CO2) concentration on global warming is considered as one of the primary environmental issues of the past two decades. The main source of CO2 emission is human activity, such as the use of fossil fuels in transportation and industrial plants. Following the release of Kyoto Protocol in 1997, effective ways of controlling CO2 emissions received much attention. As a result, various materials such as activated carbon, zeolites, and carbon nanotubes (CNTs) were investigated for their CO2 adsorbing properties. CNTs were reported to have CO2 adsorption capability twice that of activated carbon, hence they received the most attention. In the current study, single walled carbon nanotubes (SWNTs) were used as one dimensional nanoporous materials and their CO2 adsorption capacity was analyzed with Molecular Dynamics simulations. Results indicated that SWNTs are excellent CO2 adsorbers and their effectiveness increase at low CO2 concentrations. In addition, we showed that by varying temperature, CO2 can be removed from the SWNTs, providing a simple method to reuse SWNTs.

  5. 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...

  6. Highly precise atmospheric oxygen measurements as a tool to detect leaks of carbon dioxide from Carbon Capture and Storage sites

    OpenAIRE

    Leeuwen van, Charlotte

    2015-01-01

    In Carbon Capture and Storage (CCS), carbon dioxide (CO2) from fossil fuel combustion is stored underground into a geological formation. Although the storage of CO2 is considered as safe, leakage to the atmosphere is an important concern and monitoring is necessary. Detecting and quantifying leaks of CO2 in the atmosphere is, however, difficult due to the rapid mixing of the emitted CO2 with the surroundings and the high natural variability of the CO2 concentration. In this thesis we present ...

  7. 超临界CO2技术在制备电磁屏蔽材料中的应用%Preparation of electromagnetic shielding material using supercritical carbon dioxide

    Institute of Scientific and Technical Information of China (English)

    郑光洪; 蒋学军; 赵习; 掘照夫

    2011-01-01

    Supercritical CO2(SCCO2) fluid technique is applied to the pretreatment of ramie fabrics. It can remove the impurities and lignin with good swelling action. Flexible electromagnetic shielding material is prepared by electroless copper plating with the organometallic complex Palladium (ll)-hexafluoroacetylacetonate, which is dissolved in SCCO2 and impregnated into the ramie fibers. Results show that the impregnation effect can be improved with alcohol as a co-solvent, and the ramie fabric features high electromagnetic shielding effect up to 63 -92 dB in frequency range from 10 to 1 000 MHz.%超临界二氧化碳流体对苎麻纤维有明显的膨化作用.采用超临界二氧化碳流体( SCCO2)技术对苎麻织物进行预处理,能够有效去除苎麻纤维中的杂质及木质素;利用超临界二氧化碳流体的高溶解能力,将六氟乙酰丙酮钯(Ⅱ)溶解并注入苎麻纤维中,并通过化学镀铜制备柔性抗电磁波屏蔽材料.结果表明,采用乙醇作为共溶剂,可以提高钯络合物的注入效果,再经化学镀铜,苎麻织物表现出良好的电磁屏蔽效果,在10~1 000 MHz的频率范围内,电磁屏蔽效果可达到63~92 dB.

  8. Synthesis and carbon dioxide sorption of layered double hydroxide/silica foam nanocomposites with hierarchical mesostructure

    KAUST Repository

    Fu, Liling

    2014-03-05

    Layered double hydroxides (LDHs) with a hierarchical mesostructure are successfully synthesized on mesoporous silica foams by simple impregnation and hydrothermal treatment. The as-synthesized LDH/silica foam nanocomposites show well-defined mesostructures with high surface areas, large pore volumes, and mesopores of 6-7 nm. The nanocomposites act as carbon dioxide (CO2) sorbents under simulated flue gas conditions. They also exhibit significantly enhanced CO2 capacities under high-pressure conditions and high CO2/N2 and CO2/CH4 selectivities. Respect the hierarchy: Hierarchical mesoporous layered double hydroxide (LDH) nanocomposites with high surface areas and large pore volumes are synthesized by controlled hydrothermal growth of LDH precursors on a mesoporous silica foam. The as-synthesized nanocomposites exhibit a significantly enhanced capacity and selectivity towards carbon dioxide, making them very promising candidates for carbon dioxide (CO2) separation applications. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. 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

  10. Alteration of Oceanic Nitrification Under Elevated Carbon Dioxide Concentrations

    Science.gov (United States)

    Beman, J.; Chow, C. E.; Popp, B. N.; Fuhrman, J. A.; Feng, Y.; Hutchins, D. A.

    2008-12-01

    Atmospheric carbon dioxide (CO2) concentrations are increasing exponentially and expected to double by the year 2100. Dissolution of excess CO2 in the upper ocean reduces pH, alters carbonate chemistry, and also represents a potential resource for autotrophic organisms that convert inorganic carbon into biomass--including a broad spectrum of marine microbes. These bacteria and archaea drive global biogeochemical cycles of carbon and nitrogen and constitute the vast majority of biomass in the sea, yet their responses to reduced pH and increased pCO2 remain largely undocumented. Here we show that elevated pCO2 may sharply reduce nitrification rates and populations of nitrifying microorganisms in the ocean. Multiple experiments were performed in the Sargasso Sea and the Southern California Bight under glacial maximum (193 ppm), present day (390 ppm), and projected (750 ppm) pCO2 concentrations, over time scales from hours to multiple days, and at depths of 45 m to 240 m. Measurement of nitrification rates using isotopically-labeled nitrogen showed 2-5 fold reduction under elevated pCO2--as well as an increase under glacial maximum pCO2. Marine Crenarchaeota are likely involved in nitrification as ammonia-oxidizing archaea (AOA) and are among the most abundant microbial groups in the ocean, yet this group decreased by 40-80% under increased pCO2, based on quantification of both 16S rRNA and ammonia monooxygenase (amoA) gene copies. Crenarchaeota also steadily declined over the course of multiple days under elevated pCO2, whereas ammonia-oxidizing (AOB) and nitrite-oxidizing bacteria (NOB) were more variable in their responses or were not detected. These findings suggest that projected increases in pCO2 and subsequent decreases in pH may strongly influence marine biogeochemistry and microbial community structure in the sea.

  11. Experimental reactivity with CO2 of clayey cap-rock and carbonate reservoir of the Paris basin

    International Nuclear Information System (INIS)

    The constant increase in the quantity of carbon dioxide in the atmosphere is regarded as being the principal cause of the current global warming. The geological sequestration of CO2 seems to be an ideal solution to reduce the increase of greenhouse gases (of which CO2) in the atmosphere but only if the reservoir's cap-rock keep its integrity for several hundreds or thousands of years. Batch experimental simulations were conducted to observe the reactivity of a cap-rock made of clay and a carbonate reservoir with CO2 at 80 C and 150 C for a pressure of 150 bar with an equilibrated water. The analytical protocol established allowed to compare the rocks before and after experimentations finding a very low reactivity, focusing on aluminium in phyllosilicates. Textural analysis shows that CO2 does not affect the properties of adsorption and the specific surface. The study of carbonate reservoir by confocal microscopy has revealed phenomena of dissolution-precipitation which have no significant impact on chemistry and structure of the reservoir. The numerical simulations carried out on mineral reference as calcium montmorillonite or clinochlore show a significant reaction in the presence of CO2 not achieved experimentally, probably due to lacunas in the thermodynamic databases or the kinetics of reactions. The simulations on Bure show no reaction on the major minerals confirming the results with batch experiments. (author)

  12. Significance of pCO2 values in determining carbonate chemistry in groundwater of Pondicherry region,India

    Institute of Scientific and Technical Information of China (English)

    S Chidambaram; M.V Prasanna; U Karmegam; C Singaraja; S Pethaperumal; R Manivannan; P Anandhan; K Tirumalesh

    2011-01-01

    The partial pressure of Carbon-Dioxide plays a significant role in the water chemistry.It reflects the geochemical process and relates to the saturation index (SI) of the Carbonate minerals.A total number of 98 samples were collected from layered sequential aquifers like Alluvium,Upper Cuddalore sandstone,Lower Cuddalore Sandstone and Cretaceous formations,during Pre-Monsoon and Post-Monsoon seasons.Chemical parameters of groundwater such as pH,EC,TDS,Na+,K+,Ca2+,Mg2+,Cl-,HCO-3,SO2-4,pO3-4 and H4SiO4 were determined.The study shows that an increase in the log pCO2 values during water-rock interaction which influences the process of mineral dissolution.Saturation index of the carbonate minerals like Calcite,Aragonite,Dolomite and Magnesite were derived and compared with the log pCO2 values.In both the seasons the decreasing log pCO2 increases the saturation index of most of the carbonate minerals studied.The saturation index of almost all carbonate minerals during both the seasons showed negative correlation irrespective of the formation.Log pCO2 also develops a negative correlation with pH in groundwater of the study area.

  13. IMPROVING THE EFFICIENCY OF CARBON DIOXIDE SUPPLY ON UREA SYNTHESIS

    OpenAIRE

    Лавренченко, Г. К.; Копытин, А. В.; Афанасьев, С. В.; Рощенко, О. С.

    2011-01-01

    Aggregates of urea synthesis are reconstructed with the purpose decrease in specific expenses and increase their productivity. Supply of additional quantities of carbon dioxide and ammonia is necessary to increase production volumes of urea. In most cases there is a problem with the supply of СО2, as the equipment for its compression is not any necessary reserves. Installation for supply of carbon dioxide using a pump is considered. For liquefaction of CO2 at low pressure the cold of the liqu...

  14. 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.

  15. 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.

  16. Overview on CO2 Valorization: Challenge of Molten Carbonates

    OpenAIRE

    Chery, Déborah; Lair, Virginie; Cassir, Michel

    2015-01-01

    The capture and utilization of CO2 is becoming progressively one of the significant challenges in the field of energetic resources. Whatever the energetic device, it is impossible to avoid completely the production of greenhouse gas, even parting from renewable energies. Transforming CO2 into a valuable fuel, such as alcohols, CO, or even C, could constitute a conceptual revolution in the energetic bouquet offering a huge application domain. Although several routes have been tested for this p...

  17. Image of Carbon dioxide capture and storage. Analysis of reports in Dutch national newspapers; Beeldvorming over CO2 afvang en opslag. Analyse van de berichtgeving in Nederlandse landelijke dagbladen

    Energy Technology Data Exchange (ETDEWEB)

    Kliest, A. Arman Kliest Januari 2010

    2010-02-15

    Carbon Capture and Storage (CCS) has positioned itself as a newsworthy item in the Dutch media. The number of articles on CCS in the national newspapers has increased rapidly since 2005. This study focuses on the CCS demonstration project in the town of Barendrecht, which has featured regularly in the media. The analysis provides details of the portrayal of CCS in the newspapers from July 2006 to April 2009. In the first quarter of 2009 the articles became mainly negative caused by onesided and vigorous debates about the demonstration project. During the entire period of investigation there is a great variety in coverage of CCS per newspaper. The papers' different position towards the subject is noteworthy. If one believes the press, actors such as the general public, the government, environmental lobby groups and the industry position themselves very differently towards CCS. This, however, does not always correspond with their actual position. It is concluded that the national debate on CCS is captured by the papers in a partial and unbalanced way. [Dutch] Carbon Capture and Storage (CCS) is een nieuwswaardig onderwerp in de Nederlandse media. De berichtgeving over CCS is vanaf 2005 sterk toegenomen in landelijke dagbladen. Dit onderzoek focust zich op het CCS demonstratieproject in Barendrecht, dat veelvuldig in de media verschijnt. De krantenanalyse laat de vermeende houding van de kranten ten opzichte van CCS zien tussen juli 2006 tot en met april 2009. In het eerste kwartaal van 2009 berichten de dagbladen het meest negatief over het onderwerp, hetgeen wordt veroorzaakt door commotie omtrent het Barendrecht project. Gedurende de hele onderzoeksperiode is een grote variatie zichtbaar in het aantal gepubliceerde berichten per krant, als mede de verschillende houdingen die de kranten aannemen. Volgens de landelijke dagbladen varieert de positie van de actoren zoals het publiek, overheid, milieuorganisaties en de industrie. De vermeende houding komt niet

  18. Molecular transport: Catch the carbon dioxide

    Science.gov (United States)

    Kirchner, Barbara; Intemann, Barbara

    2016-05-01

    Understanding the minute details of CO2 transport is key to finding new technologies that reduce the hazardous levels of CO2 in our atmosphere. Now, the observation that the transport of CO2 in molten calcium carbonate occurs faster than standard molecular diffusion brings us one step closer.

  19. Improved model calculation of atmospheric CO2 increment in affecting carbon stock of tropical mangrove forest

    OpenAIRE

    Jana, Tapan Kumar; Ray, Raghab; Chowdhury, Chumki; Majumder, Natasha; Dutta, Manab Kumar; Mukhopadhyay, Sandip Kumar

    2013-01-01

    Because of the difficulties in setting up arrangements in the intertidal zone for free-air carbon dioxide enrichment experimentation, the responses to increasing atmospheric carbon dioxide in mangrove forests are poorly studied. This study applied box model to overcome this limitation, and the relative changes in present level of reservoirs organic carbon contents in response to the future increase of atmospheric carbon dioxide were examined in the Avicennia-dominated mangrove forest at the l...

  20. Biomimetic sequestration of CO2 in carbonate form: Role of produced waters and other brines

    International Nuclear Information System (INIS)

    The objective of our research is the development of a system resembling a CO2 scrubber, in which carbonic anhydrase catalyzes the rate of CO2 hydration for subsequent fixation into stable mineral carbonates. The present focus is on the use of produced waters as one of various possible sources of the counterions for precipitation. Carbonate precipitation has been studied from synthetic brines corresponding to a range of compositions of produced waters from the Permian and San Juan Basins, and promising results have been obtained with carbonic anhydrase. CO2 sequestration capacities are estimated to be 0.49-1.85x103 tonnes CO2/year and 1.28-2.80x105 tonnes CO2/year for the San Juan and Permian Basins, respectively, per cycle, up to ∼3mt CO2 per year total, based on the volumes of produced waters in 2002. (author)

  1. Determination of the Effect of Geological Reservoir Variability on Carbon Dioxide Storage Using Numerical Experiments Détermination de la variabilité des réservoirs géologiques sur le stockage du CO2 par la méthodologie des plans d’expériences

    Directory of Open Access Journals (Sweden)

    Diedro F.

    2013-06-01

    Full Text Available The simulations of carbon dioxide storage in sedimentary reservoirs model the fluid and gas flow and the chemical reactions which occur between the minerals (calcite and dolomite and the injected CO2 [André et al. (2007 Energy Convers. Manage. 48, 17821797; Gunter et al. (1999 Appl. Geochem. 4, 1-111. However because of the lack of data, these reservoirs are always partially known and the fitted variograms of petrophysical and mineralogical quantities are approximate. The aim is to quantify the impact of uncertainties on reservoir characteristics on the storage predictions. We focus on two operational parameters: the quantity of the stored carbon dioxide and the mean variation of the porosity. Two sources of uncertainties are examined: the draw dispersion and the approximation on the variogram parameters. To study the influence of the draw dispersion, variogram parameters are kept fixed and different simulations are run; the associated variance on the operational parameters then has the meaning of a repeatability error. In the second case, a sensibility analysis is carried out to study the influence of variogram parameters variations (sill, range, nugget effect on the CO2 storage. The chosen methodology is the designs of experiments. The simulations are carried out using reactive transport software. The studied carbonated reservoir is built in reference to the Dogger formation of Paris Basin (France [Diedro (2009 Thèse, École Nationale Supérieure des Mines de St- Étienne. This reservoir is composed of several minerals, some of them being disposed in spots. The results show that the impact of the draw dispersion remains lower than the impact of the variogram parameters. The effect of the size of the dolomite spots within the rock on the stored carbon dioxide is to be noticed. Larger spots of the dolomite field with low concentration lead to a greater precipitation of carbonate and reduction of porosity than little ,spots with higher

  2. Design and Implementation of a CO2 Flood Utilizing Advanced Reservoir Characterization and Horizontal Injection Wells In a Shallow Shelf Carbonate Approaching Waterflood Depletion, Class II

    Energy Technology Data Exchange (ETDEWEB)

    Wier, Don R. Chimanhusky, John S.; Czirr, Kirk L.; Hallenbeck, Larry; Gerard, Matthew G.; Dollens, Kim B.; Owen, Rex; Gaddis, Maurice; Moshell, M.K.

    2002-11-18

    The purpose of this project was to economically design an optimum carbon dioxide (CO2) flood for a mature waterflood nearing its economic abandonment. The original project utilized advanced reservoir characterization and CO2 horizontal injection wells as the primary methods to redevelop the South Cowden Unit (SCU). The development plans; project implementation and reservoir management techniques were to be transferred to the public domain to assist in preventing premature abandonment of similar fields.

  3. CO2-pressure swing activation for efficient production of highly porous carbons

    OpenAIRE

    Wang, Shuwen; Kaneko, Katsumi

    2015-01-01

    In this work, we describe a new type of activation method of carbon materials using pressure swing of CO2. The porosity development markedly depends on the pressure swinging frequency. The porous carbon obtained from pressure-swing activation shows an additional porosity development without pitting corrosion on the surface, which occurs on CO2 activation without pressure-swing. This phenomenon is ascribed to the enhancement of Knudsen diffusion and/or configurational diffusion of CO2 which is...

  4. On CO2 pertubation experiments: over-determination of carbonate chemistry reveals inconsistencies

    OpenAIRE

    Hoppe, C. J. M.; Langer, G.; S. D. Rokitta; Wolf-Gladrow, D. A.; Rost, B.

    2010-01-01

    Seawater carbonate chemistry is typically calculated from two measured parameters. Depending on the choice of these input parameters, discrepancies in calculated pCO2 have been recognized by marine chemists, but the significance of this phenomenon for CO2 perturbation experiments has so far not been determined. To mimic different pCO2 scenarios, two common perturbation methods for seawater carbonate chemistry (changing either DIC or TA) were applied using state-of-the-art pr...

  5. Effect of CO2 concentrations on the activity of photosynthetic CO2 fixation and extracelluar carbonic anhydrase in the marine diatom Skeletonema costatum

    Institute of Scientific and Technical Information of China (English)

    CHEN Xiongwen; GAO Kunshan

    2003-01-01

    The growth and activity of photosynthetic CO2 uptake and extracellular carbonic anhydrase (Caext) of the marine diatom Skeletonema costatum were investigated while cultured at different levels of CO2 in order to see its physiological response to different CO2 concentrations under either a low (30 μmol·m-2·s-1) or high (210 μmol·m-2·s-1) irradiance. The changes in CO2 concentrations (4-31 μmol/L) affected the growth and net photosynthesis to a greater extent under the low than under the high light regime. Caext was detected in the cells grown at 4 μmol/L CO2 but not at 31 and 12 μmol/L CO2, with its activity being about 2.5-fold higher at the high than at the low irradiance. Photo- synthetic CO2 affinity (1/ K1/2(CO2)) of the cells decreased with increased CO2 concentrations in culture. The cells cultured under the high-light show significantly higher photosynthetic CO2 affinity than those grown at the low-light level. It is concluded that the regulations of Caext activity and photosynthetic CO2 affinity are dependent not only on CO2 concentration but also on light availability, and that the development of higher Caext activity and CO2 affinity under higher light level could sufficiently support the photosynthetic demand for CO2 even at low level of CO2.

  6. 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)

  7. Summer Ice and Carbon Dioxide

    Science.gov (United States)

    Kukla, G.; Gavin, J.

    1981-10-01

    The extent of Antarctic pack ice in the summer, as charted from satellite imagery, decreased by 2.5 million square kilometers between 1973 and 1980. The U.S. Navy and Russian atlases and whaling and research ship reports from the 1930's indicate that summer ice conditions earlier in this century were heavier than the current average. Surface air temperatures along the seasonally shifting belt of melting snow between 55 degrees and 80 degrees N during spring and summer were higher in 1974 to 1978 than in 1934 to 1938. The observed departures in the two hemispheres qualitatively agree with the predicted impact of an increase in atmospheric carbon dioxide. However, since it is not known to what extent the changes in snow and ice cover and in temperature can be explained by the natural variability of the climate system or by other processes unrelated to carbon dioxide, a cause-and-effect relation cannot yet be established.

  8. 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.

  9. Carbon Deposition during CO2 Electrolysis in Ni-Based Solid-Oxide-Cell Electrodes

    DEFF Research Database (Denmark)

    Skafte, Theis Løye; Graves, Christopher R.; Blennow, P.;

    2015-01-01

    . Electrochemical impedance spectroscopy in both H2/H2O and CO/CO2 revealed an increase in resistance of the fuel electrode after each CO2 electrolysis current-voltage curve, indicating possible carbon deposition. The difference in partial oxygen pressure between inlet and outlet was analyzed to verify carbon...

  10. Carbon dioxide direct cycle modular reactor

    International Nuclear Information System (INIS)

    Recently, as the micro gas-turbine power generation is clean for environment and has high convenience, it is focused as a small size dispersion electric source for super markets, hospitals, factories, and so on. And, a modular high temperature gas reactor (PBMR) adopting the gas turbine is also focused recently, and is progressed on its construction in South Africa and reported on construction plan of the Exelon Inc. in U.S.A. PBMR has specific safety for a small size and pebble-bed reactor and also has some characters on low construction cost similar to that of LWR due to simplification and small size module adoption of its plant. The PBMR uses helium for its coolants, of which exit temperature is set for at 900degC to get higher thermal efficiency. This is because of its adoption of Brayton cycle to fast reduce the efficiency with falling temperature. However, as helium is a costly and easy-emission vapor, it is desired to alternate to cheaper and more difficult-emission vapor. Here were introduced on carbon dioxide (CO2) direct cycle using carbon dioxide with extremely higher thermal efficiency than helium and its applicability to nuclear reactors. (G.K.)

  11. Adaptation to carbon dioxide tax in shipping

    International Nuclear Information System (INIS)

    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 CO2 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

  12. Metal–organic framework-based catalysts: Chemical fixation of CO2 with epoxides leading to cyclic organic carbonates

    Directory of Open Access Journals (Sweden)

    M. Hassan eBeyzavi

    2015-01-01

    Full Text Available As a C1 feedstock, CO2 has the potential to be uniquely highly economical in both a chemical and a financial sense. In particular, the highly atom-economical acid-catalyzed cycloaddition of CO2 to epoxides to yield cyclic organic carbonates (OCs, a functionality having many important industrial applications, is an attractive reaction for the utilization of CO2 as a chemical feedstock. Metal–organic frameworks (MOFs are promising candidates in catalysis as they are a class of crystalline, porous and functional materials with remarkable properties including great surface area, high stability, open channels and permanent porosity. MOFs structure tunability and their affinity for CO2, makes them great catalysts for the formation of OCs using CO2 and epoxides. In this review, we examine MOF-based catalytic materials for the cycloaddition of carbon dioxide to epoxides. Catalysts are grouped based on the location of catalytic sites, i.e., at the struts, nodes, defect sites, or some combination thereof. Additionally, important features of each catalyst system are critically discussed.

  13. Characterization of Tropospheric Emission Spectrometer (TES CO2 for carbon cycle science

    Directory of Open Access Journals (Sweden)

    S. C. Biraud

    2009-12-01

    Full Text Available We present carbon dioxide (CO2 estimates from the Tropospheric Emission Spectrometer (TES on the EOS-Aura satellite launched in 2004. For observations between 40° S and 45° N, we find about 1 degree of freedom with peak sensitivity at 511 hPa. The estimated error is ~10 ppm for a single target and about 1.3 ppm for monthly averages on spatial scales of 20°×30°. Monthly spatially-averaged TES results from 2005–2008 processed with a uniform initial guess and prior are compared to CONTRAIL aircraft data over the Pacific ocean, aircraft data at the Southern Great Plains (SGP ARM site in the southern US, and the Mauna Loa and Samoa surface stations. Comparisons to Mauna Loa observatory show a correlation of 0.92, a standard deviation of 1.3 ppm, a predicted error of 1.2 ppm, and a ~2% low bias, which is subsequently corrected, and comparisons to SGP aircraft data over land show a correlation of 0.67 and a standard deviation of 2.3 ppm. TES data between 40° S and 45° N for 2006–2007 are compared to surface flask data, GLOBALVIEW, the Atmospheric Infrared Sounder (AIRS, and CarbonTracker. Comparison to GLOBALVIEW-CO2 ocean surface sites shows a correlation of 0.60 which drops when TES is offset in latitude, longitude, or time. At these same locations, TES shows a 0.62 and 0.67 correlation to CarbonTracker with TES observation operator at the surface and 5 km, respectively. We also conducted an observing system simulation experiment to assess the potential utility of the TES data for inverse modeling of CO2 fluxes. We find that if biases in the data and model are well characterized, the averaged data have the potential to provide sufficient information to significantly reduce uncertainty on annual estimates of regional CO2 sources and sinks. Averaged pseudo-data at 10°×10° reduced uncertainty in flux estimates by as much as 70% for some tropical regions.

  14. Using conservative and reactive tracers to monitor and verify permanent carbon dioxide storage in basalt

    Science.gov (United States)

    Hall, J. L.; Matter, J. M.; Stute, M.; Bausch, A.

    2012-12-01

    Carbon capture and storage methods can assist in reducing greenhouse gas emissions and tackling global warming. Long term, thermodynamically stable storage of carbon dioxide through mineral carbonation is one such method, in which divalent cations released from rocks such as basalt react with CO2 to form carbonates. [1] Currently used monitoring techniques for geologic CO2 storage fail to detect dissolved or chemically transformed CO2. We use conservative and reactive tracers in an ongoing pilot CO2 injection project in Iceland to characterize subsurface CO2 transport and in situ CO2-water-rock reactions. The Carbfix project in Iceland is a field scale pilot project where CO2 and H2S emissions from the Hellisheidi geothermal power plant are dissolved in groundwater and injected into a permeable basalt formation at ~500 m depth below surface. Trifluormethylsulphur pentafluoride (SF5CF3) and sulfurhexafluoride (SF6) are added as conservative tracers to the injected CO2 for the purpose of characterizing the migration of the injected CO2 in the basaltic storage reservoir. Furthermore, the injected CO2 is labeled with radiocarbon (14C) to monitor the extent of CO2-water-rock reactions and mineral carbonation. Initial results from the monitoring wells show a fast dispersion and reaction of the injected CO2. Breakthrough curves of SF6, SF5CF3 and 14C can be observed in nearby monitoring wells from samples collected and analyzed by gas chromatography or accelerator mass spectrometry, respectively. Changes in the ratios between reactive and conservative tracers demonstrate that mixing and CO2-water-rock reactions are occurring. The use of conservative and reactive tracers contributes to the monitoring, verification and accounting information needed to establish the extent and security of carbon storage and be helpful in furthering the public acceptance of geological CO2 storage via mineral carbonation as a contribution to reducing carbon dioxide emissions. [1] Oelkers, et

  15. Enhanced polystyrene surface mobility under carbon dioxide at low temperature for nanoparticle embedding control

    NARCIS (Netherlands)

    Yang, Qiuyan; Xu, Qun; Loos, Katja

    2015-01-01

    The surface properties of polystyrene (PS) films under carbon dioxide (CO2) were studied via a particle embedding technique at quite a low temperature range (308 to 323 K) in which polystyrene is typically considered to be in a glassy state without CO2. Atomic force microscope (AFM) technique with a

  16. UNDERSTANDING AND MANAGING RISKS POSED BY BRINES CONTAINING DISSOLVED CARBON DIOXIDE

    Science.gov (United States)

    Geologic disposal of supercritical carbon dioxide in saline aquifers and depleted oil and gas fields will cause large volumes of brine to become saturated with dissolved CO2 at concentrations of 50 g/l or more.  As CO2 dissolves in brine, the brine de...

  17. Carbon dioxide control in an open system that measures canopy gas exchanges

    Science.gov (United States)

    Atmospheric carbon dioxide concentration ([CO2]) effects both C3 net assimilation (A) as well as crop water use. Methods for measuring whole canopy gas exchange responses under [CO2] enrichment are needed for breeding programs aiming to develop crop cultivars resistant to stresses like drought in a...

  18. Rising carbon dioxide as a selection factor in rice/red rice competition

    Science.gov (United States)

    Carbon dioxide (CO2), along with sunlight, water, and nutrients constitutes one of the four resources needed for plants to grow. As such, the sudden increase in its concentration in the atmosphere (up 22% since 1960) could be exploited in order to boost crop yields. However, the rise in CO2 is indi...

  19. Genotypic Variation in Soybean Molecular Responses to Elevated Carbon Dioxide Concentration

    Science.gov (United States)

    A critical step in maximizing crop yield in a future of elevated atmospheric carbon dioxide concentration ([CO2]) is identifying genotypic variability in response to elevated [CO2] and understanding the molecular basis for the variation. We compared photosynthesis, leaf metabolites and global gene e...

  20. Photosynthesis in tropical cover crop legumes influenced by irradiance, external carbon dioxide concentration and temperature

    Science.gov (United States)

    In plantation crops perennial tropical legumes are grown as understory plants, receive limited irradiance, and are subjected to elevated levels of CO2 and temperature. Independent short-term effects of photosynthetic photon flux density (PPFD), external carbon dioxide concentration [CO2] and temper...

  1. The extreme carbon dioxide outburst at the Menzengraben potash mine 7 July 1953

    DEFF Research Database (Denmark)

    Hedlund, Frank Huess

    2012-01-01

    PHAST. Output from the model is inconsistent with the asphyxiation harm observed. The high-momentum release is predicted to disperse safely and never reach the ground. Carbon dioxide capture and storage (CCS) schemes will involve handling and transportation of unprecedented quantities of CO2. Case......Carbon dioxide is an asphyxiant and an irritant gas. An extreme outburst of carbon dioxide took place 7 July 1953 in a potash mine in the former East Germany. During 25 min, a large amount of CO2 was blown out of the mine shaft with great force. It was wind still and concentrated CO2 accumulated in...... a valley leading to multiple asphyxiation casualties. Based on a review of concentration–response relationships, the location of victims, and other information, it is concluded that concentrations of 10–30% carbon dioxide may have occurred 450 m from the point of release for at least 45 min. It is...

  2. Cobalamin Catalytic Centers for Stable Fuels Generation from Carbon Dioxide

    Science.gov (United States)

    Robertson, Wesley D.; Jawdat, Benmaan I.; Ennist, Nathan M.; Warncke, Kurt

    2010-03-01

    Our aim is to design and construct protein-based artificial photosynthetic systems that reduce carbon dioxide (CO2) to stable fuel forms within the robust and adaptable (βα)8 TIM-barrel protein structure. The EutB subunit of the adenosylcobalamin-dependent enzyme, ethanolamine ammonia-lyase, from Salmonella typhimurium, was selected as the protein template. This system was selected because the Co^I forms of the native cobalamin (Cbl) cofactor, and the related cobinamide (Cbi), possess redox properties that are commensurate with reduction of CO2. The kinetics of photo- (excited 5'-deazariboflavin electron donor) and chemical [Ti(III)] reduction, and subsequent reaction, of the Cbl and Cbi with CO2 are measured by time-resolved UV/visible absorption spectroscopy. Products are quantified by NMR spectroscopy. The results address the efficacy of the organocobalt catalytic centers for CO2 reduction to stable fuels, towards protein device integration.

  3. A district heating system as a sink for carbon dioxide

    International Nuclear Information System (INIS)

    Within a strategy of carbn dioxide (CO2) abatement, district heating systems, driven by small nuclear heating reactors, could be used not only to deliver sensible heat to the consumers, but also as a CO2-absorber/desorber system for the collection of diffusively scattered CO2-sources. For this, potassium carbonate (K2CO3) is dissolved in the heating system which converts into potassium bicarbonate (KHCO3) when CO2 from flue gases is absorbed. At the heating reactor CO2 is desorbed and disposed of. Hence, a district heating system could work as a 'CO2-collecting system', too. Using this additional feature of a district heating system, its so-called effective, climate-related, CO2-neutrality factor is increased by almost a factor of three compared with the direct substitution effect of the CO2-free nuclear heating energy alone. Such a hybrid system could be of interest in a transitional phase when nuclear district heating energy will penetrate into a yet fossil-fuelled heating market. (orig.)

  4. Impact of carbon dioxide co-injection on the performance of SAGD

    Energy Technology Data Exchange (ETDEWEB)

    Gates, I.D.; Wang, J. [Dept. of Chemical and Petroleum Engineering, University of Calgary (Canada); Bunio, G.; Robinson, B. [Paramount Resources (Canada)

    2011-07-01

    In the oil industry, steam assisted gravity drainage (SAGD) is used as an effective method to recover bitumen from oil sands. However, development of alternative methods is needed since SAGD is a heavy consumer of energy and emits considerable amounts of CO2. A new method consists of using carbon dioxide as a solvent along with SAGD. The aim of this study is to assess the impact of the addition of carbon dioxide on SAGD performance. Thermal reservoir simulations were carried out using the CMG simulator on a Grand Rapids oil sands reservoir. Results showed that this new method permits a large fraction of CO2 to sequestered within the reservoir and moderate carbon dioxide content does not harm SAGD performance. A steam carbon dioxide co-injection method to recover bitumen from oil sands was presented herein and it was proved to be effective at moderate carbon dioxide content.

  5. A review of the contrasting behavior of two magmatic volatiles: Chlorine and carbon dioxide

    Science.gov (United States)

    Lowenstern, J. B.

    2000-01-01

    Chlorine (Cl) and carbon dioxide (CO2) are common magmatic volatiles with contrasting behaviors. CO2 solubility increases with pressure whereas Cl solubility shows relatively little pressure or temperature effect. CO2 speciation changes with silicate melt composition, dissolving as carbonate in basaltic magmas and molecular CO2 in more silicic compositions. In H2O-bearing systems, the strongly non-ideal behavior of alkali chlorides causes unmixing of the volatile phase to form a H2O-rich vapor and a hydrosaline phase with important implications for the maximum concentration of Cl in magmas. Addition of CO2 to magma hastens immiscibility at crustal pressures (Chlorine (Cl) and carbon dioxide (CO2) are common magmatic volatiles with contrasting behaviors. CO2 solubility increases with pressure whereas Cl solubility shows relatively little pressure or temperature effect. CO2 speciation changes with silicate melt composition, dissolving as carbonate in basaltic magmas and molecular CO2 in more silicic compositions. In H2O-bearing systems, the strongly non-ideal behavior of alkali chlorides causes unmixing of the volatile phase to form a H2O-rich vapor and a hydrosaline phase with important implications for the maximum concentration of Cl in magmas. Addition of CO2 to magma hastens immiscibility at crustal pressures (<500 MPa), inducing the formation of CO2-rich vapors and Cl-rich hydrosaline melts.

  6. Photosynthetic carbon metabolism in photoautotrophic cell suspension cultures grown at low and high CO2

    International Nuclear Information System (INIS)

    Photosynthetic carbon metabolism was characterized in four photoautotrophic cell suspension cultures. There was no apparent difference between two soybeans (Glycine max) and one cotton (Gossypium hirsutum) cell line which required 5% CO2 for growth, and a unique cotton cell line that grows at ambient CO2 (660 microliters per liter). Photosynthetic characteristics in all four lines were more like C3 mesophyll leaf cells than the cell suspension cultures previously studied. The pattern of 14C-labeling reflected the high ratio of ribulosebisphosphate carboxylase to phosphoenolpyruvate carboxylase activity and showed that CO2 fixation occurred primarily by the C3 pathway. Photorespiration occurred at 330 microliters per liter CO2, 21% O2 as indicated by the synthesis of high levels of 14C-labeled glycine and serine in a pulse-chase experiment and by oxygen inhibition of CO2 fixation. Short-term CO2 fixation in the presence and absence of carbonic anhydrase showed CO2, not HCO3-, to be the main source of inorganic carbon taken up by the low CO2-requiring cotton cells. The cells did not have a CO2-concentrating mechanism as indicated by silicone oil centrifugation experiments. Carbonic anhydrase was absent in the low CO2-requiring cotton cells, present in the high CO2-requiring soybean cell lines, and absent in other high CO2 cell lines examined. Thus, the presence of carbonic anhydrase is not an essential requirement for photoautotrophy in cell suspension cultures which grow at either high or low CO2 concentrations

  7. The Arctic Ocean marine carbon cycle: evaluation of air-sea CO2 exchanges, ocean acidification impacts and potential feedbacks

    Directory of Open Access Journals (Sweden)

    N. R. Bates

    2009-11-01

    Full Text Available At present, although seasonal sea-ice cover mitigates atmosphere-ocean gas exchange, the Arctic Ocean takes up carbon dioxide (CO2 on the order of −66 to −199 Tg C year−1 (1012 g C, contributing 5–14% to the global balance of CO2 sinks and sources. Because of this, the Arctic Ocean has an important influence on the global carbon cycle, with the marine carbon cycle and atmosphere-ocean CO2 exchanges sensitive to Arctic Ocean and global climate change feedbacks. In the near-term, further sea-ice loss and increases in phytoplankton growth rates are expected to increase the uptake of CO2 by Arctic Ocean surface waters, although mitigated somewhat by surface warming in the Arctic. Thus, the capacity of the Arctic Ocean to uptake CO2 is expected to alter in response to environmental changes driven largely by climate. These changes are likely to continue to modify the physics, biogeochemistry, and ecology of the Arctic Ocean in ways that are not yet fully understood. In surface waters, sea-ice melt, river runoff, cooling and uptake of CO2 through air-sea gas exchange combine to decrease the calcium carbonate (CaCO3 mineral saturation states (Ω of seawater while seasonal phytoplankton primary production (PP mitigates this effect. Biological amplification of ocean acidification effects in subsurface waters, due to the remineralization of organic matter, is likely to reduce the ability of many species to produce CaCO3 shells or tests with profound implications for Arctic marine ecosystems

  8. The Arctic Ocean marine carbon cycle: evaluation of air-sea CO2 exchanges, ocean acidification impacts and potential feedbacks

    Directory of Open Access Journals (Sweden)

    J. T. Mathis

    2009-07-01

    Full Text Available At present, although seasonal sea-ice cover mitigates atmosphere-ocean gas exchange, the Arctic Ocean takes up carbon dioxide (CO2 on the order of −65 to −175 Tg C year−1, contributing 5–14% to the global balance of CO2 sinks and sources. Because of this, the Arctic Ocean is an important influence on the global carbon cycle, with the marine carbon cycle and atmosphere-ocean CO2 exchanges sensitive to Arctic Ocean and global climate change feedbacks. In the near-term, further sea-ice loss and increases in phytoplankton growth rates are expected to increase the uptake of CO2 by Arctic surface waters, although mitigated somewhat by surface warming in the Arctic. Thus, the capacity of the Arctic Ocean to uptake CO2 is expected to alter in response to environmental changes driven largely by climate. These changes are likely to continue to modify the physics, biogeochemistry, and ecology of the Arctic Ocean in ways that are not yet fully understood. In surface waters, sea-ice melt, river runoff, cooling and uptake of CO2 through air-sea gas exchange combine to decrease the calcium carbonate (CaCO3 mineral saturation states (Ω of seawater that is counteracted by seasonal phytoplankton primary production (PP. Biological processes drive divergent trajectories for Ω in surface and subsurface waters of Arctic shelves with subsurface water experiencing undersaturation with respect to aragonite and calcite. Thus, in response to increased sea-ice loss, warming and enhanced phytoplankton PP, the benthic ecosystem of the Arctic shelves are expected to be negatively impacted by the biological amplification of ocean acidification. This in turn reduces the ability of many species to produce CaCO3 shells or tests with profound implications for Arctic marine ecosystems.

  9. Sea-ice melt CO2-carbonate chemistry in the western Arctic Ocean: meltwater contributions to air-sea CO2 gas exchange, mixed layer properties and rates of net community production under sea ice

    Directory of Open Access Journals (Sweden)

    N. R. Bates

    2014-01-01

    Full Text Available The carbon dioxide (CO2-carbonate chemistry of sea-ice melt and co-located, contemporaneous seawater has rarely been studied in sea ice covered oceans. Here, we describe the CO2-carbonate chemistry of sea-ice melt (both above sea ice as "melt ponds" and below sea ice as "interface waters" and mixed layer properties in the western Arctic Ocean in the early summer of 2010 and 2011. At nineteen stations, the salinity (~ 0.5 to –1 and total alkalinity (TA; ~ 30 to –1 of above-ice melt pond water was low compared to water in the underlying mixed layer. The partial pressure of CO2 (pCO2 in these melt ponds was highly variable (~ 1500 μatm with the majority of melt ponds acting as potentially strong sources of CO2 to the atmosphere. The pH of melt pond waters was also highly variable ranging from mildly acidic (6.1 to 7 to slightly more alkaline than underlying seawater (8 to 10.7. All of observed melt ponds had very low (3 minerals such as aragonite (Ωaragonite. Our data suggests that sea ice generated "alkaline" or "acidic" melt pond water. This melt-water chemistry dictates whether the ponds are sources of CO2 to the atmosphere or CO2 sinks. Below-ice interface water CO2-carbonate chemistry data also indicated substantial generation of alkalinity, presumably owing to dissolution of calcium CaCO3 in sea ice. The interface waters generally had lower pCO2 and higher pH/Ωaragonite than the co-located mixed layer beneath. Sea-ice melt thus contributed to the suppression of mixed layer pCO2 enhancing the surface ocean's capacity to uptake CO2 from the atmosphere. Meltwater contributions to changes in mixed–layer DIC were also used to estimate net community production rates (mean of 46.9 ±29.8 g C m–2 for the early-season period under sea-ice cover. Although sea-ice melt is a transient seasonal feature, above-ice melt pond coverage can be substantial (10 to > 50% and under-ice interface melt water is ubiquitous during this spring/summer sea

  10. Breakthrough adsorption study of a commercial activated carbon for pre-combustion CO2 capture

    OpenAIRE

    García López, Susana; Gil Matellanes, María Victoria; Fernández Martín, Claudia; Pis Martínez, José Juan; Rubiera González, Fernando; Pevida García, Covadonga

    2011-01-01

    In this study a commercial activated carbon (Norit R2030CO2) was assessed as a solid sorbent for precombustion CO2 capture. This technology involves the removal of CO2 from the shifted-syngas prior to the generation of electricity and the production of high-purity clean H2. The CO2 equilibrium adsorption capacity and breakthrough time were evaluated in a flow-through system where the adsorbent was subjected to four consecutive adsorption–desorption cycles. A CO2/H2/N2 gas mixture (20/70/10 vo...

  11. Understanding Geochemical Impacts of Carbon Dioxide Leakage from Carbon Capture and Sequestration

    Science.gov (United States)

    US EPA held a technical Geochemical Impact Workshop in Washington, DC on July 10 and 11, 2007 to discuss geological considerations and Area of Review (AoR) issues related to geologic sequestration (GS) of Carbon Dioxide (CO2). Seventy=one (71) representatives of the electric uti...

  12. Localized surface plasmon fiber device coated with carbon nanotubes for the specific detection of CO2

    Science.gov (United States)

    Allsop, T.; Arif, R.; Neal, R.; Kalli, K.; Kundrát, V.; Rozhin, A.; Culverhouse, P.; Webb, D. J.

    2015-08-01

    We explored the potential of a carbon nanotube (CNT) coating working in conjunction with a recently developed localized surface plasmon (LSP) device (based upon a nanostructured thin film consisting of of nano-wires of platinum) with ultra-high sensitivity to changes in the surrounding index. The uncoated LSP sensor's transmission resonances exhibited a refractive index sensitivity of Δλ/Δn ~ -6200nm/RIU and ΔΙ/Δn ~5900dB/RIU, which is the highest reported spectral sensitivity of a fiber optic sensor to bulk index changes within the gas regime. The complete device provides the first demonstration of the chemically specific gas sensing capabilities of CNTs utilizing their optical characteristics. This is proven by investigating the spectral response of the sensor before and after the adhesion of CNTs to alkane gases along with carbon dioxide. The device shows a distinctive spectral response in the presence of gaseous CO2 over and above what is expected from general changes in the bulk refractive index. This fiber device yielded a limit of detection of 150ppm for CO2 at a pressure of one atmosphere. Additionally the adhered CNTs actually reduce sensitivity of the device to changes in bulk refractive index of the surrounding medium. The polarization properties of the LSP sensor resonances are also investigated and it is shown that there is a reduction in the overall azimuthal polarization after the CNTs are applied. These optical devices offer a way of exploiting optically the chemical selectivity of carbon nanotubes, thus providing the potential for real-world applications in gas sensing in many inflammable and explosive environments.

  13. Study of CO2 recovery in a carbonate fuel cell tri-generation plant

    Science.gov (United States)

    Rinaldi, Giorgio; McLarty, Dustin; Brouwer, Jack; Lanzini, Andrea; Santarelli, Massimo

    2015-06-01

    The possibility of separating and recovering CO2 in a biogas plant that co-produces electricity, hydrogen, and heat is investigated. Exploiting the ability of a molten carbonate fuel cell (MCFC) to concentrate CO2 in the anode exhaust stream reduces the energy consumption and complexity of CO2 separation techniques that would otherwise be required to remove dilute CO2 from combustion exhaust streams. Three potential CO2 concentrating configurations are numerically simulated to evaluate potential CO2 recovery rates: 1) anode oxidation and partial CO2 recirculation, 2) integration with exhaust from an internal combustion engine, and 3) series connection of molten carbonate cathodes initially fed with internal combustion engine (ICE) exhaust. Physical models have been calibrated with data acquired from an operating MCFC tri-generating plant. Results illustrate a high compatibility between hydrogen co-production and CO2 recovery with series connection of molten carbonate systems offering the best results for efficient CO2 recovery. In this case the carbon capture ratio (CCR) exceeds 73% for two systems in series and 90% for 3 MCFC in series. This remarkably high carbon recovery is possible with 1.4 MWe delivered by the ICE system and 0.9 MWe and about 350 kg day-1 of H2 delivered by the three MCFC.

  14. Numerical investigation on the expansion of supercritical carbon dioxide jet

    International Nuclear Information System (INIS)

    Supercritical carbon dioxide (SC-CO2) fluid is characterized by low rock breaking threshold pressure and high rock breaking rate. Meanwhile, SC-CO2 fluid has relatively low viscosity near to gas and high density near to liquid. So, it has great advantages in drilling and rock breaking over water. In this paper, numerical study of SC-CO2 flowing through a nozzle is presented. The purpose of this simulation is to ascertain why the SC-CO2 jet flow has better ability in drilling and rock breaking than the water jet flow. The simulation model was controlled by the RANS equations together with the continuity equation as well as the energy equation. The realizable k-epsilon turbulence model was adopted to govern the turbulent characteristics. Pressure boundary conditions were applied to the inlet and outlet boundary. The properties of carbon dioxide and water were described by UDF. It is found that: (1) under the same boundary conditions, the decay of dimensionless central axial velocity and dynamic pressure of water is quicker than that of the SC-CO2, and the core length of SC-CO2 jet is about 4.5 times of the nozzle diameter, which is 1 times longer than that of the water; (2) With the increase of inlet pressure or the decrease of outlet pressure, the dimensionless central axial velocity and dynamic pressure attenuation of water keeps the same, while the decay of central axial velocity of SC-CO2 turns gentle; (3) the change of central axial temperature of SC-CO2 is more complex than that of the water

  15. Carbon dioxide conversion by means of coplanar dielectric barrier discharges

    Science.gov (United States)

    Schiorlin, Milko; Klink, Rouven; Brandenburg, Ronny

    2016-08-01

    To face the worldwide problem of anthropogenic carbon dioxide (CO2) emission new techniques have to be developed. One approach for carbon capture utilization (CCU) is the conversion of CO2 to more valuable chemicals, e.g., carbon monoxide (CO) by means of non-thermal plasma generated at ambient conditions and supplied by excess energy from renewable sources. This paper reports about the effect of the admixture of inert gases, namely nitrogen or argon to CO2 in a coplanar dielectric barrier discharge (DBD). Systematic experiments were conducted to investigate the effects of applied voltage, frequency, flowrate and CO2 concentration in the influent. The composition of products, energy efficiency and yield were determined. Within the investigated parameter ranges, the maximum conversion of CO2 to CO efficiency of 1% was achieved when the specific input energy was 190 J L-1, whereas the maximum CO yield of 0.7% was achieved when the specific input energy was 210 J L-1. In conclusion, the energy efficiency can be significantly increased by operating the plasma in a diluted CO2 gas. Contribution to the topical issue "6th Central European Symposium on Plasma Chemistry (CESPC-6)", edited by Nicolas Gherardi, Ester Marotta and Cristina Paradisi

  16. The streaming potential of liquid carbon dioxide in Berea sandstone

    OpenAIRE

    Moore, Jeffrey R.; Glaser, S D; Morrison, H.F.; Hoversten, G M

    2004-01-01

    We report here, for the first time, evolution of the streaming potential coupling coefficient as liquid carbon dioxide infiltrates Berea sandstone. Using 125 Omega-m tap water, the coupling coefficient determined before and after each CO2 flood of five samples averaged approximately -30 mV/0.1 MPa. After liquid CO2 passed through the specimens displacing all mobile pore water, trapped water remained and the coupling coefficient was approximately -3 mV/0.1 MPa. A bound water limit of the coupl...

  17. 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

  18. TIR-1 carbon dioxide laser system for fusion

    Science.gov (United States)

    Adamovich, V. A.; Anisimov, V. N.; Afonin, E. A.; Baranov, V. Iu.; Borzenko, V. L.; Kozochkin, S. M.; Maliuta, D. D.; Satov, Iu. A.; Sebrant, A. Iu.; Smakovski, Iu. B.

    1980-03-01

    The paper examines the TIR-1 carbon dioxide laser system for fusion. The current efforts are concentrated on (1) the microsecond laser pulse plasma heating in solenoids and theta pinches, and (2) nanosecond CO2 laser utilization for inertial confinement fusion. The TIR-1 system was designed to develop nanosecond CO2 laser technology and to study laser-target interaction at 10 microns. This system consists of an oscillator-preamplifier that produces about 1-nsec laser pulse with an energy contrast ratio of 1 million, a large triple-pass amplifier, and a target chamber with diagnostic equipment.

  19. The streaming potential of liquid carbon dioxide in Brea Sandstone

    OpenAIRE

    Moore, J.; GLASER, S; Morrison, F.; Hoversten, G M

    2004-01-01

    We report here, for the first time, evolution of the streaming potential coupling coefficient as liquid carbon dioxide infiltrates Berea sandstone. Using 125 Omega-m tap water, the coupling coefficient determined before and after each CO2 flood of five samples averaged approximately -30 mV/0.1 MPa. After liquid CO2 passed through the specimens displacing all mobile pore water, trapped water remained and the coupling coefficient was approximately -3 mV/0.1 MPa. A bound water limit of the ...

  20. The reduction of carbon dioxide with photo-active catalyst

    International Nuclear Information System (INIS)

    In our study, we focused on the preparation of a photoactive catalyst capable of reducing CO2 with water under the influence of UV A-VIS radiation. We prepared two different photocatalysts of Fe-ZSM-5 and Pt-Fe-ZSM-5 Pt-ULT by oxidative polymerization of thiophene on the zeolite Na-ZSM-5 Pt in the presence of FeCl3. We tested these photocatalysts for capability of reducing CO2. The results of gas chromatography show that the photocatalysts prepared by us are able to reduce carbon dioxide to organic compounds.

  1. Perspectives of nuclear power and carbon dioxide abatement

    International Nuclear Information System (INIS)

    The papers presented at the conference particularly look at reactor safety aspects and nuclear power programmes worldwide, which are discussed in connection with the demand for ensuring power supplies in the future, and reducing atmospheric pollution by carbon dioxide. The CO2 problem as it is encountered at present and strategies for CO2 abatement are explained in some papers, whereas other papers are concerned with nuclear power reactors and the related major aspects of safety engineering, nuclear fuel supply and radioactive waste management, and further development of nuclear installations, comparing the technical details and pro and cons of LWR, HTR, and breeder reactor programmes. (DG)

  2. Carbon Dioxide Management on the International Space Station

    Science.gov (United States)

    Burlingame, Katie

    2016-01-01

    The International Space Station (ISS) is a manned laboratory operating in orbit around the Earth that was built and is currently operated by several countries across the world. The ISS is a platform for novel scientific research as well as a testbed for technologies that will be required for the next step in space exploration. In order for astronauts to live on ISS for an extended period of time, it is vital that on board systems consistently provide a clean atmosphere. One contaminant that must be removed from the atmosphere is carbon dioxide (CO2). CO2 levels on ISS are higher than those on Earth and can cause crew members to experience symptoms such as headaches, lethargy and mental slowness. A variety of systems exist on ISS to remove carbon dioxide, including adsorbent technologies which can be reused and testbed technologies for future space vehicles.

  3. Indomethacin lowers optic nerve oxygen tension and reduces the effect of carbonic anhydrase inhibition and carbon dioxide breathing

    DEFF Research Database (Denmark)

    Pedersen, D B; Eysteinsson, T; Stefánsson, E;

    2004-01-01

    Prostaglandins are important in blood flow regulation. Carbon dioxide (CO(2)) breathing and carbonic anhydrase inhibition increase the oxygen tension in the retina and optic nerve. To study the mechanism of this effect and the role of cyclo-oxygenase in the regulation of optic nerve oxygen tension...... (ONPO(2)), the authors investigated how indomethacin affects ONPO(2) and the ONPO(2) increases caused by CO(2) breathing and carbonic anhydrase inhibition in the pig....

  4. 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.

  5. Oxygenator Exhaust Capnography for Prediction of Arterial Carbon Dioxide Tension During Hypothermic Cardiopulmonary Bypass

    OpenAIRE

    Baraka, Anis; El-Khatib, Mohamad; Muallem, Eva; Jamal, Salim; Haroun-Bizri, Sania; Aouad, Marie

    2005-01-01

    Continuous monitoring and control of arterial carbon dioxide tension (PaCO2) during cardiopulmonary bypass (CPB) is essential. A reliable, accurate, and inexpensive system is not currently available. This study was undertaken to assess whether the continuous monitoring of oxygenator exhaust carbon dioxide tension (PexCO2) can be used to reflect PaCO2 during CPB. A total of 33 patients undergoing CPB for cardiac surgery were included in the study. During normothermia (37°C) and stable hypother...

  6. Carbon Dioxide Removal Troubleshooting aboard the International Space Station (ISS) during Space Shuttle (STS) Docked Operations

    Science.gov (United States)

    Matty, Christopher M.; Cover, John M.

    2009-01-01

    The International Space Station (ISS) represents a largely closed-system habitable volume which requires active control of atmospheric constituents, including removal of exhaled Carbon Dioxide (CO2). The ISS provides a unique opportunity to observe system requirements for (CO2) removal. CO2 removal is managed by the Carbon Dioxide Removal Assembly (CDRA) aboard the US segment of ISS and by Lithium Hydroxide (LiOH) aboard the Space Shuttle (STS). While the ISS and STS are docked, various methods are used to balance the CO2 levels between the two vehicles, including mechanical air handling and management of general crew locations. Over the course of ISS operation, several unexpected anomalies have occurred which have required troubleshooting, including possible compromised performance of the CDRA and LiOH systems, and possible imbalance in CO2 levels between the ISS and STS while docked. This paper will cover efforts to troubleshoot the CO2 removal systems aboard the ISS and docked STS.

  7. Conversion of carbon dioxide to valuable petrochemicals:An approach to clean development mechanism

    Institute of Scientific and Technical Information of China (English)

    Farnaz Tahriri Zangeneh; Saeed Sahebdelfar; Maryam Takht Ravanchi

    2011-01-01

    The increase of atmospheric carbon dioxide and the global warming due to its greenhouse effect resulted in worldwide concerns. On the other hand, carbon dioxide might be considered as a valuable and renewable carbon source. One approach to reduce carbon dioxide emissions could be its capture and recycle via transformation into chemicals using the technologies in C1 chemistry. Despite its great interest, there are difficulties in CO2 separation on the one hand, and thermodynamic stability of carbon dioxide molecule rendering its chemical activity low on the other hand. Carbon dioxide has been already used in petrochemical industries for production of limited chemicals such as urea.The utilization of carbon dioxide does not necessarily involve development of new processes, and in certain processes such as methanol synthesis and methane steam reforming, addition of CO2 into the feed results in its utilization and increases carbon efficiency. In other cases,modifications in catalyst and/or processes, or even new catalysts and processes, are necessary. In either case, catalysis plays a crucial role in carbon dioxide conversion and effective catalysts are required for commercial realization of the related processes. Technologies for CO2 utilization are emerging after many years of research and development efforts.

  8. Thermodynamics and Widom lines in supercritical carbon dioxide

    OpenAIRE

    Fomin, Yu. D.; Ryzhov, V.N.; Tsiok, E. N.; Brazhkin, V. V.; Trachenko, K.

    2014-01-01

    Behavior of supercritical fluids attracts a lot of attention nowadays. It is important both from the point of view of fundamental science and technological applications. However, up to now the progress in the field is rather moderate. In this article we report a computational study of supercritical carbon dioxide which is one of the most important fluids for chemical industry. We study the response functions of $CO_2$ in supercritical regime and calculate the locations of their maxima (Widom ...

  9. Per Capita Carbon Dioxide Emissions: Convergence or Divergence?

    OpenAIRE

    Aldy, Joseph

    2005-01-01

    Understanding and considering the distribution of per capita carbon dioxide (CO2) emissions is important in designing international climate change proposals and incentives for participation. I evaluate historic international emissions distributions and forecast future distributions to assess whether per capita emissions have been converging or will converge. I find evidence of convergence among 23 member countries of the Organisation for Economic Co-operation and Development (OECD), whereas e...

  10. Carbon-Based Adsorbents for Postcombustion CO2 Capture: A Critical Review.

    Science.gov (United States)

    Creamer, Anne Elise; Gao, Bin

    2016-07-19

    The persistent increase in atmospheric CO2 from anthropogenic sources makes research directed toward carbon capture and storage imperative. Current liquid amine absorption technology has several drawbacks including hazardous byproducts and a high-energy requirement for regeneration; therefore, research is ongoing to develop more practical methods for capturing CO2 in postcombustion scenarios. The unique properties of carbon-based materials make them specifically promising for CO2 adsorption at low temperature and moderate to high partial pressure. This critical review aims to highlight the development of carbon-based solid sorbents for postcombustion CO2 capture. Specifically, it provides an overview of postcombustion CO2 capture processes with solid adsorbents and discusses a variety of carbon-based materials that could be used. This review focuses on low-cost pyrogenic carbon, activated carbon (AC), and metal-carbon composites for CO2 capture. Further, it touches upon the recent progress made to develop metal organic frameworks (MOFs) and carbon nanomaterials and their general CO2 sorption potential. PMID:27257991

  11. Ocean Surface Carbon Dioxide Fugacity Observed from Space

    Science.gov (United States)

    Liu, W. Timothy; Xie, Xiaosu

    2014-01-01

    We have developed and validated a statistical model to estimate the fugacity (or partial pressure) of carbon dioxide (CO2) at sea surface (pCO2sea) from space-based observations of sea surface temperature (SST), chlorophyll, and salinity. More than a quarter million in situ measurements coincident with satellite data were compiled to train and validate the model. We have produced and made accessible 9 years (2002-2010) of the pCO2sea at 0.5 degree resolutions daily over the global ocean. The results help to identify uncertainties in current JPL Carbon Monitoring System (CMS) model-based and bottom-up estimates over the ocean. The utility of the data to reveal multi-year and regional variability of the fugacity in relation to prevalent oceanic parameters is demonstrated.

  12. Monitoring of Geological CO2, based on Wireless Sensor Networks

    OpenAIRE

    Ms. Wagh Sushama Mohan*; Prof. Mr. Devi R.J.

    2014-01-01

    Carbon Capture and Storage (CCS), also known as Carbon Capture and Sequestration, includes geological storage CO2. Safe, long-term geological storage (sequestration) of CO2 also requires a continuous monitoring system to detect CO2 leakage from reservior. This paper gives details about a remote carbon dioxide (CO2) concentration monitoring system developed, based on the technologies of wireless sensor networks, in allusion to the gas leakage monitoring requirement for CO2 capture ...

  13. CO2 mitigation potential of mineral carbonation with industrial alkalinity sources in the United States.

    Science.gov (United States)

    Kirchofer, Abby; Becker, Austin; Brandt, Adam; Wilcox, Jennifer

    2013-07-01

    The availability of industrial alkalinity sources is investigated to determine their potential for the simultaneous capture and sequestration of CO2 from point-source emissions in the United States. Industrial alkalinity sources investigated include fly ash, cement kiln dust, and iron and steel slag. Their feasibility for mineral carbonation is determined by their relative abundance for CO2 reactivity and their proximity to point-source CO2 emissions. In addition, the available aggregate markets are investigated as possible sinks for mineral carbonation products. We show that in the U.S., industrial alkaline byproducts have the potential to mitigate approximately 7.6 Mt CO2/yr, of which 7.0 Mt CO2/yr are CO2 captured through mineral carbonation and 0.6 Mt CO2/yr are CO2 emissions avoided through reuse as synthetic aggregate (replacing sand and gravel). The emission reductions represent a small share (i.e., 0.1%) of total U.S. CO2 emissions; however, industrial byproducts may represent comparatively low-cost methods for the advancement of mineral carbonation technologies, which may be extended to more abundant yet expensive natural alkalinity sources. PMID:23738892

  14. Arterial and end-tidal carbon dioxide difference in pediatric intensive care

    Directory of Open Access Journals (Sweden)

    Chulananda Dias Goonasekera

    2014-01-01

    Full Text Available Background and Aim: Arterial carbon dioxide tension (PaCO 2 is considered the gold standard for scrupulous monitoring in pediatric intensive care unit (PICU, but it is invasive, laborious, expensive, and intermittent. The study aims to explore when we can use end-tidal carbon dioxide tension (P ET CO 2 as a reliable, continuous, and noninvasive monitor of arterial CO 2 Materials and Methods: Concurrent P ET CO 2 , fraction of inspired oxygen, PaCO 2 , and arterial oxygen tension values of clinically stable children on mechanical ventilation were recorded. Children with extra-pulmonary ventriculoatrial shunts were excluded. The P ET CO 2 and PaCO 2 difference and its variability and reproducibility were studied. Results: A total of 624 concurrent readings were obtained from 105 children (mean age [SD] 5.53 [5.43] years requiring invasive bi-level positive airway pressure ventilation in the PICU. All had continuous P ET CO 2 monitoring and an arterial line for blood gas measurement. The mean (SD number of concurrent readings obtained from each child, 4-6 h apart was 6.0 (4.05. The P ET CO 2 values were higher than PaCO 2 in 142 observations (22.7%. The PaCO 2 -P ET CO 2 difference was individual admission specific (ANOVA, P < 0.001. The PaCO 2 -P ET CO 2 difference correlated positively with the alveolar-arterial oxygen tension [P(A-aO 2 ] difference (ρ = 0.381 P < 0.0001. There was a fixed bias between the P ET CO 2 and PaCO 2 measuring methods, difference +0.66 KPa (95% confidence interval: +0.57 to +0.76. Conclusions: The PaCO 2 -P ET CO 2 difference was individual specific. It was not affected by the primary disorder leading to the ventilation.

  15. Techno-economic evaluation of different CO2-based processes for dimethyl carbonate production

    DEFF Research Database (Denmark)

    Kongpanna, Pichayapan; Pavarajarn, Varong; Gani, Rafiqul;

    2015-01-01

    In this work, several chemical processes for production of dimethyl carbonate (DMC) based on CO2 utilization are evaluated. Four CO2-based processes for production of DMC are considered: (1) direct synthesis from CO2 and methanol; (2) synthesis from urea; (3) synthesis from propylene carbonate; and...... (4) synthesis from ethylene carbonate. The processes avoid the use of toxic chemicals such as phosgene, CO and NO that are required in conventional DMC production processes. From preliminary thermodynamic analysis, the yields of DMC are found to have the following order (higher to lower): ethylene...... carbonate route > urea route > propylene carbonate route > direct synthesis from CO2. Therefore, only the urea and ethylene carbonate routes are further investigated by comparing their performances with the commercial BAYER process on the basis of kg of DMC produced at a specific purity. The ethylene...

  16. Carbon dioxide level and form of soil nitrogen regulate assimilation of atmospheric ammonia in young trees

    OpenAIRE

    Lucas C. R. Silva; Alveiro Salamanca-Jimenez; Timothy A. Doane; Horwath, William R.

    2015-01-01

    The influence of carbon dioxide (CO2) and soil fertility on the physiological performance of plants has been extensively studied, but their combined effect is notoriously difficult to predict. Using Coffea arabica as a model tree species, we observed an additive effect on growth, by which aboveground productivity was highest under elevated CO2 and ammonium fertilization, while nitrate fertilization favored greater belowground biomass allocation regardless of CO2 concentration. A pulse of labe...

  17. TOPICAL REVIEW Advances in principal factors influencing carbon dioxide adsorption on zeolites

    OpenAIRE

    Danielle Bonenfant et al

    2008-01-01

    We report the advances in the principal structural and experimental factors that might influence the carbon dioxide (CO2) adsorption on natural and synthetic zeolites. The CO2 adsorption is principally govern by the inclusion of exchangeable cations (countercations) within the cavities of zeolites, which induce basicity and an electric field, two key parameters for CO2 adsorption. More specifically, these two parameters vary with diverse factors including the nature, distribution and number o...

  18. DEVELOPMENT OF ADSORBENTS FOR THE CAPTURE AND STORAGE OF HYDROGEN AND CARBON DIOXIDE BY MAGNETRON SPUTTERING

    OpenAIRE

    Roberts, Christopher

    2013-01-01

    Concerns about climate change have rejuvenated global efforts in reducing carbon dioxide (CO2) emissions. Tactics include capture and sequestration of CO2 from point sources and the promotion of hydrogen (H2) as a “transport fuel”. Current H2 vehicles use high pressure H2 tanks which lack the convenience of their fossil fuel counterparts and present potential safety hazards. Development of adsorbent materials that reduce the energetic costs of H2 and CO2 capture, facilitatin...

  19. Kinetics of absorption of carbon dioxide into aqueous potassium salt of proline

    DEFF Research Database (Denmark)

    Paul, Subham; Thomsen, Kaj

    2012-01-01

    with KPr for the above mentioned concentration and temperature range. Following the reaction mechanism of CO2 with primary and secondary alkanolamies, the reaction of CO2 with KPr is also described using zwitterionic mechanism. Based on the pseudo-first-order condition for the CO2 absorption, the......The absorption of carbon dioxide (CO2) into aqueous solution of potassium prolinate (KPr) are studied at 303, 313, and 323K within the salt concentration range of 0.5–3.0kmolm−3 using a wetted wall column absorber. The experimental results are used to interpret the kinetics of the reaction of CO2...

  20. Sequestration of Carbon Dioxide with Enhanced Gas Recovery-CaseStudy Altmark, North German Basin

    Energy Technology Data Exchange (ETDEWEB)

    Rebscher, Dorothee; Oldenburg, Curtis M.

    2005-10-12

    Geologic carbon dioxide storage is one strategy for reducingCO2 emissions into the atmosphere. Depleted natural gas reservoirs are anobvious target for CO2 storage due to their proven record of gascontainment. Germany has both large industrial sources of CO2 anddepleting gas reservoirs. The purpose of this report is to describe theanalysis and modeling performed to investigate the feasibility ofinjecting CO2 into nearly depleted gas reservoirs in the Altmark area inNorth Germany for geologic CO2 storage with enhanced gasrecovery.

  1. Sea-ice melt CO2-carbonate chemistry in the western Arctic Ocean: meltwater contributions to air-sea CO2 gas exchange, mixed layer properties and rates of net community production under sea ice

    Science.gov (United States)

    Bates, N. R.; Garley, R.; Frey, K. E.; Shake, K. L.; Mathis, J. T.

    2014-01-01

    The carbon dioxide (CO2)-carbonate chemistry of sea-ice melt and co-located, contemporaneous seawater has rarely been studied in sea ice covered oceans. Here, we describe the CO2-carbonate chemistry of sea-ice melt (both above sea ice as "melt ponds" and below sea ice as "interface waters") and mixed layer properties in the western Arctic Ocean in the early summer of 2010 and 2011. At nineteen stations, the salinity (~ 0.5 to 1500 μatm) with the majority of melt ponds acting as potentially strong sources of CO2 to the atmosphere. The pH of melt pond waters was also highly variable ranging from mildly acidic (6.1 to 7) to slightly more alkaline than underlying seawater (8 to 10.7). All of observed melt ponds had very low ( 50%) and under-ice interface melt water is ubiquitous during this spring/summer sea-ice retreat. Our observations contribute to growing evidence that sea-ice CO2-carbonate chemistry is highly variable and its contribution to the complex factors that influence the balance of CO2 sinks and sources (and thereby ocean acidification) is difficult to predict in an era of rapid warming and sea ice loss in the Arctic Ocean.

  2. Effects of elevated carbon dioxide and sucrose concentrations on Arabidopsis thaliana root architecture and anatomy

    International Nuclear Information System (INIS)

    Plant root growth is known to be influenced by higher levels of atmospheric carbon dioxide (CO2). Roots of some species grown in hydroponics under elevated CO2 concentrations may be more competitive sinks for photosynthetic assimilates than roots grown under lower CO2 conditions. Root branching patterns may also be influenced by elevated CO2 concentrations. Studies have also shown that factors such as soil compaction, salinity and the availability of nitrate, phosphorous, oxygen and water also influence root growth, and the effects of higher CO2 on roots can be confounded by such environmental factors. This study evaluated the effects of elevated carbon dioxide and sucrose concentrations on Arabidopsis thaliana root growth, morphology, and architecture. Both ambient and elevated CO2 levels were used along with various sucrose concentrations. The study revealed that A. thaliana plants grown on a phytagar medium in small chambers with elevated CO2 had longer roots, more lateral root growth than plants grown in ambient CO2. Roots in elevated CO2 were found to have wider root diameters, and more secondary growth. The addition of sucrose to the media closely resembled the effects of elevated CO2. In addition, the increase in sucrose concentration had a bigger effect on root morphology under ambient, than elevated CO2. Therefore, both elevated CO2 and increased sucrose concentrations promote root growth by increasing their number, length, and diameter. The dichotomy branching index (DBI) also dropped resulting in a more dichotomous branching pattern. 34 refs., 5 figs

  3. Carbon-14 as an indicator of CO2 pollution in cities

    International Nuclear Information System (INIS)

    The combustion of fossil fuels in cities, and especially in industrial areas, releases large quantities of carbon dioxide into the local atmosphere. This carbon dioxide does not contain carbon-14, with the result that the carbon-14 content of the atmospheric carbon dioxide is locally depleted. The degree of depletion provides a measure for the carbon dioxide pollution at the sampling site. Since growing plants represent a convenient average sample of the carbon dioxide in the air, the leaves of deciduous trees can be used for comparing the magnitude of local pollution in different localities during the summer growing period. A series of leaf samples collected in 1973 from Europe, North America and South Africa reveals the expected differences in the degree of pollution. Extreme instances occur in Scholven (Ruhrgebiet, Germany), where the average day-time carbon dioxide content during the summer months is found to be 8.7% above normal, and in Manhatten, New York City, where the corresponding figure is 6.4%. The technique can easily be extended to include the winter months by directly absorbing carbon dioxide in a hydroxide solution during different seasons. The proposed method is sensitive but much less time-consuming than the continuous measurement of the carbon dioxide concentration in the air. It thus lends itself to the monitoring of impact areas of pollution. (author)

  4. Fundamental Science for Geologic Carbon Sequestration: Molecular Probes for Understanding Wet CO2 Interaction with Caprock Minerals (Invited)

    Science.gov (United States)

    Rosso, K. M.; White, D.; Murphy, E. M.; Hu, J.; Hoyt, D. W.; Wang, Z.; Lea, A. S.; Schaef, H. T.; McGrail, P.

    2009-12-01

    Capture and storage of carbon dioxide and other greenhouse gases in deep geologic formations represents one of the most promising options for minimizing the impacts of greenhouse gases on climate change. A critical issue is to demonstrate in a scientifically defensible manner that CO2 will remain stored over the long-term in the geological formation where it is injected. With regards to mineral-fluid interaction, the majority of previous research has focused on mineral reactivity in aqueous solutions containing CO2. However, at the caprock-fluid interface, interaction with the supercritical CO2 (scCO2) phase itself may become more important as the buoyant plume slowly displaces or dessicates residual aqueous solution. Mechanisms of mineral interfacial reactions with wet or water-saturated CO2 are unknown. The measurement of kinetic and thermodynamic data for mineral transformation reactions in these fluids present unique challenges. New experimental tools under development at Pacific Northwest National Laboratory are enabling in situ characterization of mineral transformation processes in scCO2/H2O fluids with molecular resolution. 29Si and 13C magic angle sample spinning nuclear magnetic resonance spectroscopy of metal carbonation reactions of model magnesium silicate minerals (e.g., Mg2SiO4 forsterite) in scCO2 shows initial transformation to MgCO3 magnesite within 20 hours at 80 atm and 80°C only when water is present for nucleophilic attack on Mg-O-Si. High pressure infrared spectroscopy detects unique spectral signatures for H2O and D2O dissolved in trace quantities (mineral surfaces in contact with scCO2 fluids. High-pressure x-ray diffraction will enable phase identification in situ. Collectively, this set of capabilities provides a unique platform for elucidating the role of water for catalyzing mineral transformation to metal carbonates and provides a means for determining effective kinetic constants. Understanding and accurately representing chemical

  5. Capnography: monitoring CO2.

    Science.gov (United States)

    Casey, Georgina

    2015-10-01

    MONITORING RESPIRATORY and metabolic function by using capnography to measure end tidal carbon dioxide is standard practice in anaesthesia. It is also becoming more common in intensive care units and during procedural sedation. End tidal carbon dioxide (EtCO2) monitoring may also be used to assess effectiveness of cardiopulmonary resuscitation. Capnography is now emerging in general medical and surgical wards to monitor respiratory depression in patients using opioid analgesics. Using EtCO2 to monitor respiratory function offers many benefits over pulse oximetry. It is important to understand the differences between these two monitoring methods, and why capnography is increasingly favoured in many situations. An understanding of the physiological processes involved in CO2 excretion allows nurses to use capnography in a safe and meaningful way, while monitoring at-risk patients in acute care. PMID:26638570

  6. Continuous flow isotope ratio mass spectrometry of carbon dioxide trapped as strontium carbonate

    International Nuclear Information System (INIS)

    The isotopic signal provided by differential discrimination against atmospheric carbon dioxide (13CO2) by C3 and C4 plant photosynthetic pathways is being widely used to study the processes of carbon (C) fixation, soil organic matter formation, and mineralization in nature. These studies have been facilitated by the availability of automated C and nitrogen (N) combustion analyzers (ANCA) combined with continuous flow isotope ratio mass spectrometers (CFIRMS). Analysis of 13CO2 in these instruments requires consistent sample mass for best precision, a requirement that is easily satisfied for soil and tissue samples by adjusting sample weight. Consistent CO2 sample size is much more difficult to achieve using gas handling systems for samples of headspace gases when CO2 concentrations vary widely. Long storage of gaseous samples also is difficult. Extended respiration studies are most easily conducted by trapping CO2 in alkali and conversion to an insoluble carbonate. Thermal decomposition of the carbonate in an on-line ANCA allows consistent and optimal CO2 sample mass to be obtained. The use of precipitated carbonates also facilitates storage of samples and enables full automation of sample analysis using an ANCA interfaced to a CFIRMS. Calcium (Ca), strontium (Sr), and barium (Ba) carbonates were tested. Strontium carbonate (SrCO3) with the addition of vanadium pentoxide (V2O5) as a combustion catalyst was found most suitable

  7. Evidence for Carbonate Surface Complexation during Forsterite Carbonation in Wet Supercritical Carbon Dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Loring, John S.; Chen, Jeffrey; Benezeth Ep Gisquet, Pascale; Qafoku, Odeta; Ilton, Eugene S.; Washton, Nancy M.; Thompson, Christopher J.; Martin, Paul F.; McGrail, B. Peter; Rosso, Kevin M.; Felmy, Andrew R.; Schaef, Herbert T.

    2015-07-14

    Continental flood basalts are attractive formations for geologic sequestration of carbon dioxide because of their reactive divalent-cation containing silicates, such as forsterite (Mg2SiO4), suitable for long-term trapping of CO2 mineralized as metal carbonates. The goal of this study was to investigate at a molecular level the carbonation products formed during the reaction of forsterite with supercritical CO2 (scCO2) as a function of the concentration of H2O adsorbed to the forsterite surface. Experiments were performed at 50 °C and 90 bar using an in situ IR titration capability, and post-reaction samples were examined by ex situ techniques, including SEM, XPS, FIB-TEM, TGA-MS, and MAS-NMR. Carbonation products and reaction extents varied greatly with adsorbed H2O. We show for the first time evidence of Mg-carbonate surface complexation under wet scCO2 conditions. Carbonate is found to be coordinated to Mg at the forsterite surface in a predominately bidentate fashion at adsorbed H2O concentrations below 27 µmol/m2. Above this concentration and up to 76 µmol/m2, monodentate coordinated complexes become dominant. Beyond a threshold adsorbed H2O concentration of 76 µmol/m2, crystalline carbonates continuously precipitate as magnesite, and the particles that form are hundreds of times larger than the estimated thicknesses of the adsorbed water films of about 7 to 15 Å. At an applied level, these results suggest that mineral carbonation in scCO2 dominated fluids near the wellbore and adjacent to caprocks will be insignificant and limited to surface complexation, unless adsorbed H2O concentrations are high enough to promote crystalline carbonate formation. At a fundamental level, the surface complexes and their dependence on adsorbed H2O concentration give insights regarding forsterite dissolution processes and magnesite nucleation and growth.

  8. Absorption of carbon dioxide in waste tanks

    International Nuclear Information System (INIS)

    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

  9. Pre-Combustion Carbon Dioxide Capture by a New Dual Phase Ceramic-Carbonate Membrane Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Jerry

    2014-09-30

    This report documents synthesis, characterization and carbon dioxide permeation and separation properties of a new group of ceramic-carbonate dual-phase membranes and results of a laboratory study on their application for water gas shift reaction with carbon dioxide separation. A series of ceramic-carbonate dual phase membranes with various oxygen ionic or mixed ionic and electronic conducting metal oxide materials in disk, tube, symmetric, and asymmetric geometric configurations was developed. These membranes, with the thickness of 10 μm to 1.5 mm, show CO2 permeance in the range of 0.5-5×10-7 mol·m-2·s-1·Pa-1 in 500-900oC and measured CO2/N2 selectivity of up to 3000. CO2 permeation mechanism and factors that affect CO2 permeation through the dual-phase membranes have been identified. A reliable CO2 permeation model was developed. A robust method was established for the optimization of the microstructures of ceramic-carbonate membranes. The ceramic-carbonate membranes exhibit high stability for high temperature CO2 separations and water gas shift reaction. Water gas shift reaction in the dual-phase membrane reactors was studied by both modeling and experiments. It is found that high temperature syngas water gas shift reaction in tubular ceramic-carbonate dual phase membrane reactor is feasible even without catalyst. The membrane reactor exhibits good CO2 permeation flux, high thermal and chemical stability and high thermal shock resistance. Reaction and separation conditions in the membrane reactor to produce hydrogen of 93% purity and CO2 stream of >95% purity, with 90% CO2 capture have been identified. Integration of the ceramic-carbonate dual-phase membrane reactor with IGCC process for carbon dioxide capture was analyzed. A methodology was developed to identify optimum operation conditions for a membrane tube of given dimensions that would treat coal syngas with targeted performance. The calculation results show that the dual-phase membrane reactor could

  10. ECOLOGICAL, ECONOMIC AND SOCIAL ISSUES OF IMPLEMENTING CARBON DIOXIDE SEQUESTRATION TECHNOLOGIES IN THE OIL AND GAS INDUSTRY IN RUSSIA

    OpenAIRE

    Alexey Cherepovitsyn; Alina Ilinova

    2016-01-01

    The objective of this paper is to define the main approaches to the implementation of carbon dioxide sequestration technologies in the oil and gas industry in Russia, and also to identify ecological, economic and social issues of their usage. Promotion of the technology of carbon dioxide (CO2) sequestration by means of capturing and injecting it into underground reservoirs is a promising mechanism of reducing carbon dioxide concentration. Carbon capture and storage (CCS) technologies might be...

  11. 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. PMID:15474375

  12. A Numerical Study on Combining CO2 Mineral Carbonation and Geothermal Energy Development

    Science.gov (United States)

    Wan, Y.; Xu, T.; Pruess, K.

    2010-12-01

    There is growing interest in the novel concept of operating Enhanced Geothermal Systems (EGS) with CO2 instead of water as heat transmission fluid. Initial studies have suggested that CO2 may achieve larger rates of heat extraction, and can offer geologic storage of carbon as an ancillary benefit. A fully developed EGS with CO2 would consist of three distinct zones, (1) a central zone or “core” in which all aqueous phase has been removed by dissolution into the flowing CO2 stream, so that the reservoir fluid is a single supercritical CO2 phase; (2) a surrounding intermediate zone, in which the reservoir fluid consists of a two-phase water-CO2 mixture; and (3) an outer or peripheral zone, in which the reservoir fluid is a single aqueous phase with dissolved CO2. Fluid-rock interactions in EGS operated with CO2 are expected to be vastly different in zones with an aqueous phase present, as compared to the central reservoir zone with anhydrous supercritical CO2. We have performed chemically reactive transport (TOUGHREACT ) modeling to investigate fluid-rock interactions and CO2 mineral carbonation of an EGS operated with CO2. The quartz monzodiorite unit at the Enhanced Geothermal Systems (EGS) site at Desert Peak (Nevada) was taken as an example. A geothermal injection well system with supercritical CO2 injection was simulated to (1) investigate mineral dissolution/precipitation and associated porosity changes, and (2) impacts on reservoir growth and longevity, with ramifications for sustaining energy recovery, for estimating CO2 loss rates, and for figuring tradeoffs between power generation and CO2 mineralization (geologic storage).

  13. Conductive Graphitic Carbon Nitride as an Ideal Material for Electrocatalytically Switchable CO2 Capture

    OpenAIRE

    Xin Tan; Liangzhi Kou; Tahini, Hassan A.; Smith, Sean C.

    2015-01-01

    Good electrical conductivity and high electron mobility of the sorbent materials are prerequisite for electrocatalytically switchable CO2 capture. However, no conductive and easily synthetic sorbent materials are available until now. Here, we examined the possibility of conductive graphitic carbon nitride (g-C4N3) nanosheets as sorbent materials for electrocatalytically switchable CO2 capture. Using first-principle calculations, we found that the adsorption energy of CO2 molecules on g-C4N3 n...

  14. Highly integrated CO2 capture and conversion: Direct synthesis of cyclic carbonates from industrial flue gas

    KAUST Repository

    Barthel, Alexander

    2016-02-08

    Robust and selective catalytic systems based on early transition metal halides (Y, Sc, Zr) and organic nucleophiles were found able to quantitatively capture CO2 from diluted streams via formation of hemicarbonate species and to convert it to cyclic organic carbonates under ambient conditions. This observation was exploited in the direct and selective chemical fixation of flue gas CO2 collected from an industrial exhaust, affording high degrees of CO2 capture and conversion.

  15. Effects of high CO2 levels on dynamic photosynthesis: carbon gain, mechanisms, and environmental interactions.

    Science.gov (United States)

    Tomimatsu, Hajime; Tang, Yanhong

    2016-05-01

    Understanding the photosynthetic responses of terrestrial plants to environments with high levels of CO2 is essential to address the ecological effects of elevated atmospheric CO2. Most photosynthetic models used for global carbon issues are based on steady-state photosynthesis, whereby photosynthesis is measured under constant environmental conditions; however, terrestrial plant photosynthesis under natural conditions is highly dynamic, and photosynthetic rates change in response to rapid changes in environmental factors. To predict future contributions of photosynthesis to the global carbon cycle, it is necessary to understand the dynamic nature of photosynthesis in relation to high CO2 levels. In this review, we summarize the current body of knowledge on the photosynthetic response to changes in light intensity under experimentally elevated CO2 conditions. We found that short-term exposure to high CO2 enhances photosynthetic rate, reduces photosynthetic induction time, and reduces post-illumination CO2 burst, resulting in increased leaf carbon gain during dynamic photosynthesis. However, long-term exposure to high CO2 during plant growth has varying effects on dynamic photosynthesis. High levels of CO2 increase the carbon gain in photosynthetic induction in some species, but have no significant effects in other species. Some studies have shown that high CO2 levels reduce the biochemical limitation on RuBP regeneration and Rubisco activation during photosynthetic induction, whereas the effects of high levels of CO2 on stomatal conductance differ among species. Few studies have examined the influence of environmental factors on effects of high levels of CO2 on dynamic photosynthesis. We identified several knowledge gaps that should be addressed to aid future predictions of photosynthesis in high-CO2 environments. PMID:27094437

  16. 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

  17. Transformation and utilization of carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Bhanage, Bhalchandra M. [Institute of Chemical Technology, Mumbai (India). Dept. of Chemistry; Arai, Masahiko (ed.) [Hokkaido Univ., Sapporo (Japan). Division of Chemical Process Engineering

    2014-04-01

    This book shows the various organic, polymeric and inorganic compounds which result from the transformation of carbon dioxide through chemical, photocatalytic, electrochemical, inorganic and biological processes. The book consists of twelve chapters demonstrating interesting examples of these reactions, depending on the types of reaction and catalyst. It also includes two chapters dealing with the utilization of carbon dioxide as a reaction promoter and presents a wide range of examples of chemistry and chemical engineering with carbon dioxide.

  18. Elevated CO2 effects on plant carbon, nitrogen, and water relations: six important lessons from FACE.

    Science.gov (United States)