WorldWideScience

Sample records for bench-scale steam reforming

  1. TWR Bench-Scale Steam Reforming Demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, D.W.; Soelberg, N.R.

    2003-05-21

    The Idaho Nuclear Technology and Engineering Center (INTEC) was home to nuclear fuel reprocessing activities for decades at the Idaho National Engineering and Environmental Laboratory. As a result of the reprocessing activities, INTEC has accumulated approximately one million gallons of acidic, radioactive, sodium-bearing waste (SBW). The purpose of this demonstration was to investigate a reforming technology, offered by ThermoChem Waste Remediation, LLC, (TWR) for treatment of SBW into a ''road ready'' waste form that would meet the waste acceptance criteria for the Waste Isolation Pilot Plant (WIPP). TWR is the licensee of Manufacturing Technology Conservation International (MTCI) steam-reforming technology in the field of radioactive waste treatment. A non-radioactive simulated SBW was used based on the known composition of waste tank WM-180 at INTEC. Rhenium was included as a non-radioactive surrogate for technetium. Data was collected to determine the nature and characteristics of the product, the operability of the technology, the composition of the off-gases, and the fate of key radionuclides (cesium and technetium) and volatile mercury compounds. The product contained a low fraction of elemental carbon residues in the cyclone and filter vessel catches. Mercury was quantitatively stripped from the product but cesium, rhenium (Tc surrogate), and the heavy metals were retained. Nitrate residues were about 400 ppm in the product and NOx destruction exceeded 86%. The demonstration was successful.

  2. TWR Bench-Scale Steam Reforming Demonstration

    Energy Technology Data Exchange (ETDEWEB)

    D. W. Marshall; N. R. Soelberg

    2003-05-01

    The Idaho Nuclear Technology and Engineering Center (INTEC) was home to nuclear fuel reprocessing activities for decades at the Idaho National Engineering and Environmental Laboratory. As a result of the reprocessing activities, INTEC has accumulated approximately one million gallons of acidic, radioactive, sodium-bearing waste (SBW). The purpose of this demonstration was to investigate a reforming technology, offered by ThermoChem Waste Remediation, LLC, (TWR) for treatment of SBW into a "road ready" waste form that would meet the waste acceptance criteria for the Waste Isolation Pilot Plant (WIPP). TWR is the licensee of Manufacturing Technology Conservation International (MTCI) steam-reforming technology in the field of radioactive waste treatment. A non-radioactive simulated SBW was used based on the known composition of waste tank WM-180 at INTEC. Rhenium was included as a non-radioactive surrogate for technetium. Data was collected to determine the nature and characteristics of the product, the operability of the technology, the composition of the off-gases, and the fate of key radionuclides (cesium and technetium) and volatile mercury compounds. The product contained a low fraction of elemental carbon residues in the cyclone and filter vessel catches. Mercury was quantitatively stripped from the product but cesium, rhenium (Tc surrogate), and the heavy metals were retained. Nitrate residues were about 400 ppm in the product and NOx destruction exceeded 86%. The demonstration was successful.

  3. THOR Bench-Scale Steam Reforming Demonstration

    International Nuclear Information System (INIS)

    The Idaho Nuclear Technology and Engineering Center (INTEC) was home to nuclear fuel reprocessing activities for decades at the Idaho National Engineering and Environmental Laboratory. As a result of the reprocessing activities, INTEC has accumulated approximately one million gallons of acidic, radioactive, sodium-bearing waste (SBW). The purpose of this demonstration was to investigate a reforming technology, offered by THORsm Treatment Technologies, LLC, for treatment of SBW into a ''road ready'' waste form that would meet the waste acceptance criteria for the Waste Isolation Pilot Plant (WIPP). A non-radioactive simulated SBW was used based on the known composition of waste tank WM-180 at INTEC. Rhenium was included as a non-radioactive surrogate for technetium. Data was collected to determine the nature and characteristics of the product, the operability of the technology, the composition of the off-gases, and the fate of key radionuclides (cesium and technetium) and volatile mercury compounds. The product contained a low fraction of elemental carbon residues in the cyclone and filter vessel catches. Mercury was quantitatively stripped from the product but cesium, rhenium (Tc surrogate), and the heavy metals were retained. Nitrates were not detected in the product and NOx destruction exceeded 98%. The demonstration was successful

  4. Steam Reforming, 6-in. Bench-Scale Design and Testing Project -- Technical and Functional Requirements Description

    Energy Technology Data Exchange (ETDEWEB)

    Losinski, Sylvester John; Marshall, Douglas William

    2002-08-01

    Feasibility studies and technology development work are currently being performed on several processes to treat radioactive liquids and solids currently stored at the Idaho Nuclear Technology and Engineering Center (INTEC), located within the Idaho National Engineering and Environmental Laboratory (INEEL). These studies and development work will be used to select a treatment process for treatment of the radioactive liquids and solids to meet treatment milestones of the Settlement Agreement between the Department of Energy and the State of Idaho. One process under consideration for treating the radioactive liquids and solids, specifically Sodium-Bearing Waste (SBW) and tank heel solids, is fluid bed steam reforming (FBSR). To support both feasibility and development studies a bench-scale FBSR is being designed and constructed. This report presents the technical and functional requirements, experimental objectives, process flow sheets, and equipment specifications for the bench-scale FBSR.

  5. BENCH-SCALE STEAM REFORMING OF ACTUAL TANK 48H WASTE

    Energy Technology Data Exchange (ETDEWEB)

    Burket, P; Gene Daniel, G; Charles Nash, C; Carol Jantzen, C; Michael Williams, M

    2008-09-25

    Fluidized Bed Steam Reforming (FBSR) has been demonstrated to be a viable technology to remove >99% of the organics from Tank 48H simulant, to remove >99% of the nitrate/nitrite from Tank 48H simulant, and to form a solid product that is primarily carbonate based. The technology was demonstrated in October of 2006 in the Engineering Scale Test Demonstration Fluidized Bed Steam Reformer1 (ESTD FBSR) at the Hazen Research Inc. (HRI) facility in Golden, CO. The purpose of the Bench-scale Steam Reformer (BSR) testing was to demonstrate that the same reactions occur and the same product is formed when steam reforming actual radioactive Tank 48H waste. The approach used in the current study was to test the BSR with the same Tank 48H simulant and same Erwin coal as was used at the ESTD FBSR under the same operating conditions. This comparison would allow verification that the same chemical reactions occur in both the BSR and ESTD FBSR. Then, actual radioactive Tank 48H material would be steam reformed in the BSR to verify that the actual tank 48H sample reacts the same way chemically as the simulant Tank 48H material. The conclusions from the BSR study and comparison to the ESTD FBSR are the following: (1) A Bench-scale Steam Reforming (BSR) unit was successfully designed and built that: (a) Emulated the chemistry of the ESTD FBSR Denitration Mineralization Reformer (DMR) and Carbon Reduction Reformer (CRR) known collectively as the dual reformer flowsheet. (b) Measured and controlled the off-gas stream. (c) Processed real (radioactive) Tank 48H waste. (d) Met the standards and specifications for radiological testing in the Savannah River National Laboratory (SRNL) Shielded Cells Facility (SCF). (2) Three runs with radioactive Tank 48H material were performed. (3) The Tetraphenylborate (TPB) was destroyed to > 99% for all radioactive Bench-scale tests. (4) The feed nitrate/nitrite was destroyed to >99% for all radioactive BSR tests the same as the ESTD FBSR. (5) The

  6. Steam reforming of methane in a bench-scale membrane reactor at realistic working conditions

    Energy Technology Data Exchange (ETDEWEB)

    Saric, M.; Van Delft, Y.C.; Sumbharaju, R.; Meyer, D.F.; De Groot, A.

    2012-10-15

    In this study, a bench-scale Pd membrane reactor was used to carry out the methane steam reforming reaction under realistic operating conditions: 580C, 28 bar(a) and GHSV (Gas hourly space velocity) values up to 950 h{sup -1}. The continuous withdrawal of the H2 product resulted in a maximum CH4 conversion of 98% and a H2 production rate of 0.13 N m{sup 3} h{sup -1}. A continuous methane conversion of 86% and a hydrogen flux of 0.1 mol m{sup -2} s{sup -1} were achieved in the membrane reactor under these challenging conditions for almost 1100 h, demonstrating the great potential of membrane reformers for H2 production.

  7. Radioactive Bench-scale Steam Reformer Demonstration of a Monolithic Steam Reformed Mineralized Waste Form for Hanford Waste Treatment Plant Secondary Waste - 12306

    International Nuclear Information System (INIS)

    Hanford currently has 212,000 m3 (56 million gallons) of highly radioactive mixed waste stored in the Hanford tank farm. This waste will be processed to produce both high-level and low-level activity fractions, both of which are to be vitrified. Supplemental treatment options have been under evaluation for treating portions of the low-activity waste, as well as the liquid secondary waste from the low-activity waste vitrification process. One technology under consideration has been the THORR fluidized bed steam reforming process offered by THOR Treatment Technologies, LLC (TTT). As a follow-on effort to TTT's 2008 pilot plant FBSR non-radioactive demonstration for treating low-activity waste and waste treatment plant secondary waste, TTT, in conjunction with Savannah River National Laboratory, has completed a bench scale evaluation of this same technology on a chemically adjusted radioactive surrogate of Hanford's waste treatment plant secondary waste stream. This test generated a granular product that was subsequently formed into monoliths, using a geo-polymer as the binding agent, that were subjected to compressibility testing, the Product Consistency Test and other leachability tests, and chemical composition analyses. This testing has demonstrated that the mineralized waste form, produced by co-processing waste with kaolin clay using the TTT process, is as durable as low-activity waste glass. Testing has shown the resulting monolith waste form is durable, leach resistant, and chemically stable, and has the added benefit of capturing and retaining the majority of Tc-99, I-129, and other target species at high levels. (authors)

  8. Cesium Removal From Tanks 241-AN-103 and 241-SX-105 and 241-AZ-101 and 241-AZ-102 Composite For Testing In Bench Scale Steam Reformer

    International Nuclear Information System (INIS)

    This report documents the preparation of three actual Hanford tank waste samples for shipment to the Savannah River National Laboratory (SRNL). Two of the samples were dissolved saltcakes from tank 241-AN-103 (hereafter AN-103) and tank 241-SX-105 (hereafter SX-105); one sample was a supernate composite from tanks 241-AZ-101 and 241-AZ-102 (hereafter AZ-101/102). The preparation of the samples was executed following the test plans LAB-PLAN-10-00006, Test Plan for the Preparation of Samples from Hanford Tanks 241-SX-105, 241-AN-103, 241-AN-107, and LAB-PLN-l0-00014, Test Plan for the Preparation of a Composite Sample from Hanford Tanks 241-AZ-101 and 241-AZ-102 for Steam Reformer Testing at the Savannah River National Laboratory. All procedural steps were recorded in laboratory notebook HNF-N-274 3. Sample breakdown diagrams for AN-103 and SX-105 are presented in Appendix A. The tank samples were prepared in support of a series of treatability studies of the Fluidized Bed Steam Reforming (FBSR) process using a Bench-Scale Reformer (BSR) at SRNL. Tests with simulants have shown that the FBSR mineralized waste form is comparable to low-activity waste glass with respect to environmental durability (WSRC-STI-2008-00268, Mineralization of Radioactive Wastes by Fluidized Bed Steam Reforming (FBSR): Comparisons to Vitreous Waste Forms and Pertinent Durability Testing). However, a rigorous assessment requires long-term performance data from FBSR product formed from actual Hanford tank waste. Washington River Protection Solutions, LLC (WRPS) has initiated a Waste Form Qualification Program (WP-5.2.1-2010-001, Fluidized Bed Steam Reformer Low-level Waste Form Qualification) to gather the data required to demonstrate that an adequate FBSR mineralized waste form can be produced. The documentation of the selection process of the three tank samples has been separately reported in RPP-48824, Sample Selection Process for Bench-Scale Steam Reforming Treatability Studies Using

  9. CESIUM REMOVAL FROM TANKS 241-AN-103 & 241-SX-105 & 241-AZ-101 & 241AZ-102 COMPOSITE FOR TESTING IN BENCH SCALE STEAM REFORMER

    Energy Technology Data Exchange (ETDEWEB)

    DUNCAN JB; HUBER HJ

    2011-04-21

    This report documents the preparation of three actual Hanford tank waste samples for shipment to the Savannah River National Laboratory (SRNL). Two of the samples were dissolved saltcakes from tank 241-AN-103 (hereafter AN-103) and tank 241-SX-105 (hereafter SX-105); one sample was a supernate composite from tanks 241-AZ-101 and 241-AZ-102 (hereafter AZ-101/102). The preparation of the samples was executed following the test plans LAB-PLAN-10-00006, Test Plan for the Preparation of Samples from Hanford Tanks 241-SX-105, 241-AN-103, 241-AN-107, and LAB-PLN-l0-00014, Test Plan for the Preparation of a Composite Sample from Hanford Tanks 241-AZ-101 and 241-AZ-102 for Steam Reformer Testing at the Savannah River National Laboratory. All procedural steps were recorded in laboratory notebook HNF-N-274 3. Sample breakdown diagrams for AN-103 and SX-105 are presented in Appendix A. The tank samples were prepared in support of a series of treatability studies of the Fluidized Bed Steam Reforming (FBSR) process using a Bench-Scale Reformer (BSR) at SRNL. Tests with simulants have shown that the FBSR mineralized waste form is comparable to low-activity waste glass with respect to environmental durability (WSRC-STI-2008-00268, Mineralization of Radioactive Wastes by Fluidized Bed Steam Reforming (FBSR): Comparisons to Vitreous Waste Forms and Pertinent Durability Testing). However, a rigorous assessment requires long-term performance data from FBSR product formed from actual Hanford tank waste. Washington River Protection Solutions, LLC (WRPS) has initiated a Waste Form Qualification Program (WP-5.2.1-2010-001, Fluidized Bed Steam Reformer Low-level Waste Form Qualification) to gather the data required to demonstrate that an adequate FBSR mineralized waste form can be produced. The documentation of the selection process of the three tank samples has been separately reported in RPP-48824, Sample Selection Process for Bench-Scale Steam Reforming Treatability Studies Using

  10. Radioactive Demonstration Of Final Mineralized Waste Forms For Hanford Waste Treatment Plant Secondary Waste By Fluidized Bed Steam Reforming Using The Bench Scale Reformer Platform

    International Nuclear Information System (INIS)

    The U.S. Department of Energy's Office of River Protection (ORP) is responsible for the retrieval, treatment, immobilization, and disposal of Hanford's tank waste. Currently there are approximately 56 million gallons of highly radioactive mixed wastes awaiting treatment. A key aspect of the River Protection Project (RPP) cleanup mission is to construct and operate the Waste Treatment and Immobilization Plant (WTP). The WTP will separate the tank waste into high-level and low-activity waste (LAW) fractions, both of which will subsequently be vitrified. The projected throughput capacity of the WTP LAW Vitrification Facility is insufficient to complete the RPP mission in the time frame required by the Hanford Federal Facility Agreement and Consent Order, also known as the Tri-Party Agreement (TPA), i.e. December 31, 2047. Therefore, Supplemental Treatment is required both to meet the TPA treatment requirements as well as to more cost effectively complete the tank waste treatment mission. In addition, the WTP LAW vitrification facility off-gas condensate known as WTP Secondary Waste (WTP-SW) will be generated and enriched in volatile components such as 137Cs, 129I, 99Tc, Cl, F, and SO4 that volatilize at the vitrification temperature of 1150 C in the absence of a continuous cold cap (that could minimize volatilization). The current waste disposal path for the WTP-SW is to process it through the Effluent Treatment Facility (ETF). Fluidized Bed Steam Reforming (FBSR) is being considered for immobilization of the ETF concentrate that would be generated by processing the WTP-SW. The focus of this current report is the WTP-SW. FBSR offers a moderate temperature (700-750 C) continuous method by which WTP-SW wastes can be processed irrespective of whether they contain organics, nitrates, sulfates/sulfides, chlorides, fluorides, volatile radionuclides or other aqueous components. The FBSR technology can process these wastes into a crystalline ceramic (mineral) waste form. The

  11. RADIOACTIVE DEMONSTRATION OF FINAL MINERALIZED WASTE FORMS FOR HANFORD WASTE TREATMENT PLANT SECONDARY WASTE BY FLUIDIZED BED STEAM REFORMING USING THE BENCH SCALE REFORMER PLATFORM

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, C.; Burket, P.; Cozzi, A.; Daniel, W.; Jantzen, C.; Missimer, D.

    2012-02-02

    The U.S. Department of Energy's Office of River Protection (ORP) is responsible for the retrieval, treatment, immobilization, and disposal of Hanford's tank waste. Currently there are approximately 56 million gallons of highly radioactive mixed wastes awaiting treatment. A key aspect of the River Protection Project (RPP) cleanup mission is to construct and operate the Waste Treatment and Immobilization Plant (WTP). The WTP will separate the tank waste into high-level and low-activity waste (LAW) fractions, both of which will subsequently be vitrified. The projected throughput capacity of the WTP LAW Vitrification Facility is insufficient to complete the RPP mission in the time frame required by the Hanford Federal Facility Agreement and Consent Order, also known as the Tri-Party Agreement (TPA), i.e. December 31, 2047. Therefore, Supplemental Treatment is required both to meet the TPA treatment requirements as well as to more cost effectively complete the tank waste treatment mission. In addition, the WTP LAW vitrification facility off-gas condensate known as WTP Secondary Waste (WTP-SW) will be generated and enriched in volatile components such as {sup 137}Cs, {sup 129}I, {sup 99}Tc, Cl, F, and SO{sub 4} that volatilize at the vitrification temperature of 1150 C in the absence of a continuous cold cap (that could minimize volatilization). The current waste disposal path for the WTP-SW is to process it through the Effluent Treatment Facility (ETF). Fluidized Bed Steam Reforming (FBSR) is being considered for immobilization of the ETF concentrate that would be generated by processing the WTP-SW. The focus of this current report is the WTP-SW. FBSR offers a moderate temperature (700-750 C) continuous method by which WTP-SW wastes can be processed irrespective of whether they contain organics, nitrates, sulfates/sulfides, chlorides, fluorides, volatile radionuclides or other aqueous components. The FBSR technology can process these wastes into a crystalline

  12. Radioactive demonstration of final mineralized waste forms for Hanford waste treatment plant secondary waste (WTP-SW) by fluidized bed steam reforming (FBSR) using the bench scale reformer platform

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Burket, P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Cozzi, A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Daniel, G. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Jantzen, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Missimer, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2014-08-01

    The U.S. Department of Energy’s Office of River Protection (ORP) is responsible for the retrieval, treatment, immobilization, and disposal of Hanford’s tank waste. Currently there are approximately 56 million gallons of highly radioactive mixed wastes awaiting treatment. A key aspect of the River Protection Project (RPP) cleanup mission is to construct and operate the Waste Treatment and Immobilization Plant (WTP). The WTP will separate the tank waste into high-level and low-activity waste (LAW) fractions, both of which will subsequently be vitrified. The projected throughput capacity of the WTP LAW Vitrification Facility is insufficient to complete the RPP mission in the time frame required by the Hanford Federal Facility Agreement and Consent Order, also known as the Tri-Party Agreement (TPA), i.e. December 31, 2047. Therefore, Supplemental Treatment is required both to meet the TPA treatment requirements as well as to more cost effectively complete the tank waste treatment mission. In addition, the WTP LAW vitrification facility off-gas condensate known as WTP Secondary Waste (WTP-SW) will be generated and enriched in volatile components such as 137Cs, 129I, 99Tc, Cl, F, and SO4 that volatilize at the vitrification temperature of 1150°C in the absence of a continuous cold cap (that could minimize volatilization). The current waste disposal path for the WTP-SW is to process it through the Effluent Treatment Facility (ETF). Fluidized Bed Steam Reforming (FBSR) is being considered for immobilization of the ETF concentrate that would be generated by processing the WTP-SW. The focus of this current report is the WTP-SW.

  13. SUMMARY PLAN FOR BENCH-SCALE REFORMER AND PRODUCT TESTING TREATABILITY STUDIES USING HANFORD TANK WASTE

    Energy Technology Data Exchange (ETDEWEB)

    DUNCAN JB

    2010-08-19

    ) was found to be comparable to immobilized low-activity waste glass waste form in the initial supplemental LAW treatment technology risk assessment (Mann 2003). To confirm this hypothesis, DOE is funding a treatability study where three actual Hanford tank waste samples (containing both {sup 99}Tc and {sup 125}I) will be processed in Savannah River National Laboratory's (SRNL) Bench-Scale Reformer (BSR) to form the mineral product, similar to the granular NAS waste form, that will then be subject to a number of waste form qualification tests. In previous tests, SRNL have demonstrated that the BSR product is chemically and physically equivalent to the FBSR product (Janzen 2005). The objective of this paper is to describe the sample selection, sample preparation, and environmental and regulatory considerations for treatability studies of the FBSR process using Hanford tank waste samples at the SNRL. The SNRL will process samples in its BSR. These samples will be decontaminated in the 222-S Laboratory to remove undissolved solids and selected radioisotopes to comply with Department of Transportation (DOT) shipping regulations and to ensure worker safety by limiting radiation exposure to As Low As Reasonably Achievable (ALARA). These decontamination levels will also meet the Nuclear Regulatory Commission's (NRC's) definition of low activity waste (LAW). After the SNRL has processed the tank samples to a granular mineral form, SRNL and Pacific Northwest National Laboratory (PNNL) will conduct waste form testing on both the granular material and monoliths prepared from the granular material. The tests being performed are outlined in Appendix A.

  14. Summary Plan For Bench-Scale Reformer And Product Testing Treatability Studies Using Hanford Tank Waste

    International Nuclear Information System (INIS)

    initial supplemental LAW treatment technology risk assessment (Mann 2003). To confirm this hypothesis, DOE is funding a treatability study where three actual Hanford tank waste samples (containing both 99Tc and 125I) will be processed in Savannah River National Laboratory's (SRNL) Bench-Scale Reformer (BSR) to form the mineral product, similar to the granular NAS waste form, that will then be subject to a number of waste form qualification tests. In previous tests, SRNL have demonstrated that the BSR product is chemically and physically equivalent to the FBSR product (Janzen 2005). The objective of this paper is to describe the sample selection, sample preparation, and environmental and regulatory considerations for treatability studies of the FBSR process using Hanford tank waste samples at the SNRL. The SNRL will process samples in its BSR. These samples will be decontaminated in the 222-S Laboratory to remove undissolved solids and selected radioisotopes to comply with Department of Transportation (DOT) shipping regulations and to ensure worker safety by limiting radiation exposure to As Low As Reasonably Achievable (ALARA). These decontamination levels will also meet the Nuclear Regulatory Commission's (NRC's) definition of low activity waste (LAW). After the SNRL has processed the tank samples to a granular mineral form, SRNL and Pacific Northwest National Laboratory (PNNL) will conduct waste form testing on both the granular material and monoliths prepared from the granular material. The tests being performed are outlined in Appendix A.

  15. Biomass to hydrogen via fast pyrolysis and catalytic steam reforming

    Energy Technology Data Exchange (ETDEWEB)

    Chornet, E.; Wang, D.; Montane, D. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1995-09-01

    Fast pyrolysis of biomass results in a pyrolytic oil which is a mixture of (a) carbohydrate-derived acids, aldehydes and polyols, (b) lignin-derived substituted phenolics, and (c) extractives-derived terpenoids and fatty acids. The conversion of this pyrolysis oil into H{sub 2} and CO{sub 2} is thermodynamically favored under appropriate steam reforming conditions. Our efforts have focused in understanding the catalysis of steam reforming which will lead to a successful process at reasonable steam/carbon ratios arid process severities. The experimental work, carried out at the laboratory and bench scale levels, has centered on the performance of Ni-based catalysts using model compounds as prototypes of the oxygenates present in the pyrolysis oil. Steam reforming of acetic acid, hydroxyacetaldehyde, furfural and syringol has been proven to proceed rapidly within a reasonable range of severities. Time-on-stream studies are now underway using a fixed bed barometric pressure reactor to ascertain the durability of the catalysts and thus substantiate the scientific and technical feasibility of the catalytic reforming option. Economic analyses are being carried out in parallel to determine the opportunity zones for the combined fast pyrolysis/steam reforming approach. A discussion on the current state of the project is presented.

  16. Steam reforming of ethanol

    DEFF Research Database (Denmark)

    Trane-Restrup, Rasmus; Dahl, Søren; Jensen, Anker Degn

    2013-01-01

    Steam reforming (SR) of oxygenated species like bio-oil or ethanol can be used to produce hydrogen or synthesis gas from renewable resources. However, deactivation due to carbon deposition is a major challenge for these processes. In this study, different strategies to minimize carbon deposition on...... Ni-based catalysts during SR of ethanol were investigated in a flow reactor. Four different supports for Ni were tested and Ce0.6Zr0.4O2 showed the highest activity, but also suffered from severe carbon deposition at 600 °C or below. Operation at 600 °C or above were needed for full conversion of...... ethanol over the most active catalysts at the applied conditions. At these temperatures the offgas composition was close to the thermodynamical equilibrium. Operation at high temperatures, 700 °C and 750 °C, gave the lowest carbon deposition corresponding to 30–60 ppm of the carbon in the feed ending as...

  17. Duplex steam reformer: alternate catalyst

    International Nuclear Information System (INIS)

    The manufacturing feasibility of a duplex steam reformer tube for potential use in a high temperature gas cooled reactor has been successfully demonstrated. This technique consists of explosively expanding the inner tube into the outer tube. To successfully achieve the desired 0 to 3 mil radial gap between the tubes it is necessary to perform the expansion in two steps with an intermediate anneal. A catalyst design that would have replaced the conventional Raschig rings with a metal supported catalyst has been evaluated and it has been concluded that further development and testing are needed before fabrication of a full scale prototype is warranted. Consequently, the immediate efforts are directed towards reevaluating the incentives for developing a catalyst and the probability of successfully developing a catalyst that could be used for steam reforming

  18. STEAM REFORMING TECHNOLOGY DEMONSTRATION FOR THE DESTRUCTION OF ORGANICS ON ACTUAL DOE SAVANNAH RIVER SITE TANK 48H WASTE 9138

    Energy Technology Data Exchange (ETDEWEB)

    Burket, P

    2009-02-24

    This paper describes the design of the Bench-scale Steam Reformer (BSR); a processing unit for demonstrating steam reforming technology on actual radioactive waste [1]. It describes the operating conditions of the unit used for processing a sample of Savannah River Site (SRS) Tank 48H waste. Finally, it compares the results from processing the actual waste in the BSR to processing simulant waste in the BSR to processing simulant waste in a large pilot scale unit, the Fluidized Bed Steam Reformer (FBSR), operated at Hazen Research Inc. in Golden, CO. The purpose of this work was to prove that the actual waste reacted in the same manner as the simulant waste in order to validate the work performed in the pilot scale unit which could only use simulant waste.

  19. Development of ATSR (Auto Thermal Steam Reformer)

    International Nuclear Information System (INIS)

    'Full text:' Auto-thermal reformers are used popularly for fuel cell vehicle because they are compact and can start up quickly. On the other hand, steam reformers are used for stationary fuel cell power plant because they are good thermal efficiency. While, there are many cases using the auto- thermal reformer for stationary use with expectation of cost reduction in USA, as well. However, they are still insufficient for its durability, compactness and cost. We have been developing the new type of fuel processing system that is auto-thermal steam reformer (ATSR), which is hybrid of a conventional steam reformer (STR) and a conventional auto-thermal reformer (ATR). In this study, some proto-type of ATSR for field test were designed, tried manufacturing and tested performance and durability. And we have tried to operate with fuel cell stack to evaluate the system interface performance, that is, operability and controllability. (author)

  20. Production of hydrogen from biomass by catalytic steam reforming of fast pyrolysis oil

    Energy Technology Data Exchange (ETDEWEB)

    Czernik, S.; Wang, D.; Chornet, E. [National Renewable Energy Lab., Golden, CO (United States). Center for Renewable Chemical Technologies and Materials

    1998-08-01

    Hydrogen is the prototype of the environmentally cleanest fuel of interest for power generation using fuel cells and for transportation. The thermochemical conversion of biomass to hydrogen can be carried out through two distinct strategies: (a) gasification followed by water-gas shift conversion, and (b) catalytic steam reforming of specific fractions derived from fast pyrolysis and aqueous/steam processes of biomass. This paper presents the latter route that begins with fast pyrolysis of biomass to produce bio-oil. This oil (as a whole or its selected fractions) can be converted to hydrogen via catalytic steam reforming followed by a water-gas shift conversion step. Such a process has been demonstrated at the bench scale using model compounds, poplar oil aqueous fraction, and the whole pyrolysis oil with commercial Ni-based steam reforming catalysts. Hydrogen yields as high as 85% have been obtained. Catalyst initial activity can be recovered through regeneration cycles by steam or CO{sub 2} gasification of carbonaceous deposits.

  1. FLUIDIZED BED STEAM REFORMING TECHNOLOGY FOR ORGANIC AND NITRATE SALT SUPERNATE

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C; Michael02 Smith, M

    2007-03-30

    About two decades ago a process was developed at the Savannah River Site (SRS) to remove Cs137 from radioactive high level waste (HLW) supernates so the supernates could be land disposed as low activity waste (LAW). Sodium tetraphenylborate (NaTPB) was used to precipitate Cs{sup 137} as CsTPB. The flowsheet called for destruction of the organic TPB by acid hydrolysis so that the Cs{sup 137} enriched residue could be mixed with other HLW sludge, vitrified, and disposed of in a federal geologic repository. The precipitation process was demonstrated full scale with actual HLW waste and a 2.5 wt% Cs137 rich precipitate containing organic TPB was produced admixed with 240,000 gallons of salt supernate. Organic destruction by acid hydrolysis proved to be problematic and other disposal technologies were investigated. Fluidized Bed Steam Reforming (FBSR), which destroys organics by pyrolysis, is the current baseline technology for destroying the TPB and the waste nitrates prior to vitrification. Bench scale tests were designed and conducted at the Savannah River National Laboratory (SRNL) to reproduce the pyrolysis reactions. The formation of alkali carbonate phases that are compatible with DWPF waste pre-processing and vitrification were demonstrated in the bench scale tests. Test parameters were optimized for a pilot scale FBSR demonstration that was performed at the SAIC Science & Technology Application Research (STAR) Center in Idaho Falls, ID by Idaho National Laboratory (INL) and SRNL in 2003. An engineering scale demonstration was completed by THOR{reg_sign} Treatment Technologies (TTT) and SRNL in 2006 at the Hazen Research, Inc. test facility in Golden, CO. The same mineral carbonate phases, the same organic destruction (>99.99%) and the same nitrate/nitrite destruction (>99.99%) were produced at the bench scale, pilot scale, and engineering scale although different sources of carbon were used during testing.

  2. Design of a nuclear steam reforming plant

    International Nuclear Information System (INIS)

    The design of a plant for the steam reforming of methane using a High Temperature Reactor has been studied by CEA in connection with the G.E.G.N. This group of companies (CEA, GAZ DE FRANCE, CHARBONNAGES DE FRANCE, CREUSOT-LOIRE, NOVATOME) is in charge of studying the feasibility of the coal gasification process by using a nuclear reactor. The process is based on the hydrogenation of the coal in liquid phase with hydrogen produced by a methane steam reformer. The reformer plant is fed by a pipe of natural gas or SNG. The produced hydrogen feeds the gasification plant which could not be located on the same site. An intermediate hydrogen storage between the two plants could make the coupling more flexible. The gasification plant does not need a great deal of heat and this heat can be satisfied mostly by internal heat exchanges

  3. Biomass-to-hydrogen via fast pyrolysis and catalytic steam reforming

    Energy Technology Data Exchange (ETDEWEB)

    Chornet, E.; Wang, D.; Czernik, S. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1996-10-01

    Pyrolysis of lignocellulosic biomass and reforming the pyroligneous oils is being studied as a strategy for producing hydrogen. Novel technologies for the rapid pyrolysis of biomass have been developed in the past decade. They provide compact and efficient systems to transform biomass into vapors that are condensed to oils, with yields as high as 75-80 wt.% of the anhydrous biomass. This {open_quotes}bio-oil{close_quotes} is a mixture of aldehydes, alcohols, acids, oligomers from the constitutive carbohydrates and lignin, and some water derived from the dehydration reactions. Hydrogen can be produced by reforming the bio-oil or its fractions with steam. A process of this nature has the potential to be cost competitive with conventional means of producing hydrogen. The reforming facility can be designed to handle alternate feedstocks, such as natural gas and naphtha, if necessary. Thermodynamic modeling of the major constituents of the bio-oil has shown that reforming is possible within a wide range of temperatures and steam-to-carbon ratios. Existing catalytic data on the reforming of oxygenates have been studied to guide catalyst selection. Tests performed on a microreactor interfaced with a molecular beam mass spectrometer showed that, by proper selection of the process variables: temperature, steam-to-carbon ratio, gas hourly space velocity, and contact time, almost total conversion of carbon in the feed to CO and CO{sub 2} could be obtained. These tests also provided possible reaction mechanisms where thermal cracking competes with catalytic processes. Bench-scale, fixed bed reactor tests demonstrated high hydrogen yields from model compounds and carbohydrate-derived pyrolysis oil fractions. Reforming bio-oil or its fractions required proper dispersion of the liquid to avoid vapor-phase carbonization of the feed in the inlet to the reactor. A special spraying nozzle injector was designed and successfully tested with an aqueous fraction of bio-oil.

  4. Methane reforming with fast nuclear reactor steam

    International Nuclear Information System (INIS)

    The paper considers the concept of utilizing nuclear fast reactor (FR) with a sodium coolant for methane steam reforming. Steam conditions of a power FR, e.g. the BN-600 now operating in Russia: steam pressure P=13.2 MPa and steam temperature T=500degC, do not absolutely comply with the catalytic reactor working parameters, which produces a synthetic gas (syngas), a mix of hydrogen and carbon oxide. In this connection, the present paper addresses a possibility of utilizing steam produced in one of three independent the BN-600 loops in an amount of 640 t/h for preparing a gas-steam mixture with T=500degC and its additional heating in a converter up to the operating temperature, T=850degC, at the expense of natural gas burning or electrical energy supplying. In this case, the fraction of burned natural gas burning or electrical energy supplying. In this case, the fraction of burned natural gas significantly decreases. It is estimated that steam parameters of the BN-600 afford to obtain ∼3·105 nm3/h of hydrogen. It is also considered a concept of nuclear heat transfer to remote regions to be achieved with the aid of syngas incoming from the converter, its cooling further and transmitting through a pipeline to the place of its utilization, where it is restored into methane with the heat extraction. (author)

  5. Catalytic glycerol steam reforming for hydrogen production

    International Nuclear Information System (INIS)

    Hydrogen production from glycerol by steam reforming combine two major advantages: (i) using glycerol as raw material add value to this by product of bio-diesel production which is obtained in large quantities around the world and have a very limited utilization now, and (ii) by implication of water molecules in the reaction the efficiency of hydrogen generation is increased as each mol of glycerol produces 7 mol of H2. In this work we present the results obtained in the process of steam reforming of glycerol on Ni/Al2O3. The catalyst was prepared by wet impregnation method and characterized through different methods: N2 adsorption-desorption, XRD, TPR. The catalytic study was performed in a stainless steel tubular reactor at atmospheric pressure by varying the reaction conditions: steam/carbon ratio (1-9), gas flow (35 ml/min -133 ml/min), temperature (450-650°C). The gaseous fraction of the reaction products contain: H2, CH4, CO, CO2. The optimum reaction conditions as resulted from this study are: temperature 550°C, Gly:H2O ratio 9:1 and Ar flow 133 ml/min. In these conditions the glycerol conversion to gaseous products was 43% and the hydrogen yield was 30%

  6. Catalytic glycerol steam reforming for hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Dan, Monica, E-mail: monica.dan@itim-cj.ro; Mihet, Maria, E-mail: maria.mihet@itim-cj.ro; Lazar, Mihaela D., E-mail: diana.lazar@itim-cj.ro [National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat Street, 400293 Cluj Napoca (Romania)

    2015-12-23

    Hydrogen production from glycerol by steam reforming combine two major advantages: (i) using glycerol as raw material add value to this by product of bio-diesel production which is obtained in large quantities around the world and have a very limited utilization now, and (ii) by implication of water molecules in the reaction the efficiency of hydrogen generation is increased as each mol of glycerol produces 7 mol of H{sub 2}. In this work we present the results obtained in the process of steam reforming of glycerol on Ni/Al{sub 2}O{sub 3}. The catalyst was prepared by wet impregnation method and characterized through different methods: N{sub 2} adsorption-desorption, XRD, TPR. The catalytic study was performed in a stainless steel tubular reactor at atmospheric pressure by varying the reaction conditions: steam/carbon ratio (1-9), gas flow (35 ml/min -133 ml/min), temperature (450-650°C). The gaseous fraction of the reaction products contain: H{sub 2}, CH{sub 4}, CO, CO{sub 2}. The optimum reaction conditions as resulted from this study are: temperature 550°C, Gly:H{sub 2}O ratio 9:1 and Ar flow 133 ml/min. In these conditions the glycerol conversion to gaseous products was 43% and the hydrogen yield was 30%.

  7. Catalytic glycerol steam reforming for hydrogen production

    Science.gov (United States)

    Dan, Monica; Mihet, Maria; Lazar, Mihaela D.

    2015-12-01

    Hydrogen production from glycerol by steam reforming combine two major advantages: (i) using glycerol as raw material add value to this by product of bio-diesel production which is obtained in large quantities around the world and have a very limited utilization now, and (ii) by implication of water molecules in the reaction the efficiency of hydrogen generation is increased as each mol of glycerol produces 7 mol of H2. In this work we present the results obtained in the process of steam reforming of glycerol on Ni/Al2O3. The catalyst was prepared by wet impregnation method and characterized through different methods: N2 adsorption-desorption, XRD, TPR. The catalytic study was performed in a stainless steel tubular reactor at atmospheric pressure by varying the reaction conditions: steam/carbon ratio (1-9), gas flow (35 ml/min -133 ml/min), temperature (450-650°C). The gaseous fraction of the reaction products contain: H2, CH4, CO, CO2. The optimum reaction conditions as resulted from this study are: temperature 550°C, Gly:H2O ratio 9:1 and Ar flow 133 ml/min. In these conditions the glycerol conversion to gaseous products was 43% and the hydrogen yield was 30%.

  8. Duplex tube steam reformer development program

    International Nuclear Information System (INIS)

    Work done in partial fulfillment of Task 7 of the Duplex Steam Reformer Development Program is described. The DSR concept acts as a double barrier between a process heat high temperature reactor plant (PNP) and a closed loop chemical heat pipe (CHP) for the long distance transport of chemical energy to a remote industrial user. The current state of the DSR design is described as well as related systems and equipment. The PNP concept presented is based upon work currently underway in the Federal Republic of Germany

  9. Bench scale demonstration of the Supermethanol concept : The synthesis of methanol from glycerol derived syngas

    NARCIS (Netherlands)

    van Bennekom, J. G.; Venderbosch, R. H.; Assink, D.; Lemmens, K. P. J.; Heeres, H. J.

    2012-01-01

    An integrated process for the synthesis of methanol from aqueous glycerol involving reforming of the feed to syngas followed by methanol synthesis is successfully demonstrated in a continuous bench scale unit. Glycerol reforming was carried out at pressures of 24-27 MPa and temperatures of 948-998 K

  10. Steam Reforming of Bio-oil Model Compounds

    DEFF Research Database (Denmark)

    Trane, Rasmus; Jensen, Anker Degn; Dahl, Søren

    The steam reforming of bio-oil is a sustainable and renewable route to synthesis gas and hydrogen, where one of the main hurdles is carbon formation on the catalyst.......The steam reforming of bio-oil is a sustainable and renewable route to synthesis gas and hydrogen, where one of the main hurdles is carbon formation on the catalyst....

  11. Steam reforming of technical bioethanol for hydrogen production

    DEFF Research Database (Denmark)

    Rass-Hansen, Jeppe; Johansson, Roger; Møller, Martin Hulbek;

    2008-01-01

    Essentially all work on ethanol steam reforming so far has been carried out using simulated bioethanol feedstocks, which means pure ethanol mixed with water. However, technical bioethanol consists of a lot of different components including sugars, which cannot be easily vaporized and steam reformed....... For ethanol steam reforming to be of practical interest, it is important to avoid the energy-intensive purification steps to fuel grade ethanol. Therefore, it is imperative to analyze how technical bioethanol, with the relevant impurities, reacts during the steam reforming process. We show how three...... different distillation fractions of technical 2nd generation bioethanol, produced in a pilot plant, influence the performance of nickel- and ruthenium-based catalysts during steam reforming, and we discuss what is required to obtain high activity and long catalyst lifetime. We conclude that the use of...

  12. Bench-scale co-processing

    Energy Technology Data Exchange (ETDEWEB)

    Nafis, D.A.; Gatsis, J.G.; Lea, C.; Miller, M.A.

    1990-03-07

    The objective of this current is to extend and optimize UOP's single-stage slurry-catalyzed co-processing scheme, which has developed under previous Contract AC22-84PC70002. Particular emphasis is given to defining and improving catalyst utilization and costs, evaluating alternative and disposable slurry-catalyst systems, and improving catalyst recycle and recovery techniques. The work during this quarter involved a series of bench-scale runs using a new Mo-based slurry catalyst. The results of bench-scale Runs 24 and 25 are discussed in the following report. 7 refs., 4 figs., 3 tabs.

  13. BENCH SCALE SALTSTONE PROCESS DEVELOPMENT MIXING STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Cozzi, A.; Hansen, E.

    2011-08-03

    The Savannah River National Laboratory (SRNL) was requested to develop a bench scale test facility, using a mixer, transfer pump, and transfer line to determine the impact of conveying the grout through the transfer lines to the vault on grout properties. Bench scale testing focused on the effect the transfer line has on the rheological property of the grout as it was processed through the transfer line. Rheological and other physical properties of grout samples were obtained prior to and after pumping through a transfer line. The Bench Scale Mixing Rig (BSMR) consisted of two mixing tanks, grout feed tank, transfer pump and transfer hose. The mixing tanks were used to batch the grout which was then transferred into the grout feed tank. The contents of the feed tank were then pumped through the transfer line (hose) using a progressive cavity pump. The grout flow rate and pump discharge pressure were monitored. Four sampling stations were located along the length of the transfer line at the 5, 105 and 205 feet past the transfer pump and at 305 feet, the discharge of the hose. Scaling between the full scale piping at Saltstone to bench scale testing at SRNL was performed by maintaining the same shear rate and total shear at the wall of the transfer line. The results of scaling down resulted in a shorter transfer line, a lower average velocity, the same transfer time and similar pressure drops. The condition of flow in the bench scale transfer line is laminar. The flow in the full scale pipe is in the transition region, but is more laminar than turbulent. The resulting plug in laminar flow in the bench scale results in a region of no-mixing. Hence mixing, or shearing, at the bench scale should be less than that observed in the full scale, where this plug is non existent due to the turbulent flow. The bench scale tests should be considered to be conservative due to the highly laminar condition of flow that exists. Two BSMR runs were performed. In both cases, wall

  14. Initial study on steam reformer of high-temperature gas-cooled reactor powered steam methane reforming hydrogen production system

    International Nuclear Information System (INIS)

    Based on one-dimension quasi-homogeneous phase model, a dynamic model for single-tube steam reformer of high-temperature gas-cooled reactor was presented, and computer program was developed. Steady state calculation and analysis were performed for the steam reformer design by Japan Atomic Energy Research Institute. The results show that heat loss at the entrance of helium influences the steam reformer performance remarkably, and reaction velocity is not main factor influencing the performance. The steady state calculation results fit well with experiment results. (authors)

  15. Thermodynamic analysis of steam reforming of methane with statistical approaches

    International Nuclear Information System (INIS)

    Highlights: • Application of the statistical models in steam reforming of methane has been studied. • Quadratic polynomial equations for main factors in product was successfully fitted to the results of thermodynamic analysis. • Insignificant operative parameters were determined in polynomial equations. - Abstract: Thermodynamic analysis of steam reforming of methane has been studied by method of Gibbs free energy minimization for hydrogen or syngas production in the ranges of steam to methane from 0.5 to 3, reaction pressure from 1 to 50 bar and operative temperature from 600 to 1200 K. The important considered parameters were methane conversion, selectivity of hydrogen, selectivity of carbon monoxide, hydrogen per carbon monoxide ratio, steam per carbon monoxide ratio and coke formation. Furthermore, this study investigates on the application of the statistical models in steam reforming of methane. The effect of parameters was determined via an orthogonal second order design

  16. Methane Steam Reforming Kinetics for a Rhodium-Based Catalyst

    DEFF Research Database (Denmark)

    Jakobsen, Jon Geest; Jakobsen, M.; Chorkendorff, Ib;

    2010-01-01

    Methane steam reforming is the key reaction to produce synthesis gas and hydrogen at the industrial scale. Here the kinetics of methane steam reforming over a rhodium-based catalyst is investigated in the temperature range 500-800 A degrees C and as a function of CH4, H2O and H-2 partial pressure...... that lowers the adsorption energy at high CO coverage. The CO-CO interaction is supported by comparison with fundamental surface science studies....

  17. Assembly and operation experience of EVA II steam reforming bundle

    International Nuclear Information System (INIS)

    The main test component of the experimental facility EVA-II/ADAM-II is a helium heated steam reformer bundle with 30 tubes. The tubes are filled with a catalyst of raschig ring type. The main test of the component were related to the power dependence. A series of experiment dealt with the influence of steam/methane ratio on the carbon deposit formation

  18. Steam reforming of DOE complex waste simulants

    International Nuclear Information System (INIS)

    Sandia National Laboratories has worked with Synthetica Technologies and Manufacturing and Technology Conversion International (MTCl) to demonstrate the applicability of their commercial steam reforming technologies for treating DOE low-level mixed wastes. Previously, Synthetica successfully demonstrated destruction of a Sandia formulated lab trash simulant. During November 1994 Synthetica did not adequately process the aqueous halogenated organic liquid mixed waste simulant (MWTP-2110) formulated by the DOE Mixed Waste Integrated Program (MWIP). Testing at MTCl is ongoing and initial results appear to be favorable. Approximately 200 lbs each of the MWIP aqueous halogenated organic liquids (MWTP-2110), and absorbed aqueous and organic liquids (MWTP-3113/3114) simulants have been processed. At 1650 degree F, destruction efficiencies of greater than 99% were obtained for tetrachloroethylene, toluene, and 1,2 dichlorobenzene. Product cases consisted primarily of H2, C02, CO, and CH4 and had higher heating values of up to 355 BTU/SCF. Conclusions concerning the suitability of the MTCI process for treating DOE mixed wastes will be drawn upon the completion of testing

  19. The nuclear heated steam reformer - design and semitechnical operating experiences

    International Nuclear Information System (INIS)

    Good operating experiences of the EVA I- and EVA II-plant have been described. Therein the comparison of the different catalyst concepts has been given. Further the behaviour of the bundle of EVA II plant by isolation of individual reformer tubes as well as the performance of the bundle under transient conditions have been explained. Different design concepts for a nuclear heated steam reformer based on the concentric tubes and baffles have been given. Main points of studies are constructional details, thermohydraulic of the bundle and stress analysis. It can be shown that the present standard of knowledge allows the application of the steam reformer for coal refinement with nuclear heat. (orig.)

  20. Hydrogen-based power generation from bioethanol steam reforming

    Energy Technology Data Exchange (ETDEWEB)

    Tasnadi-Asztalos, Zs., E-mail: tazsolt@chem.ubbcluj.ro; Cormos, C. C., E-mail: cormos@chem.ubbcluj.ro; Agachi, P. S. [Babes-Bolyai University, Faculty of Chemistry and Chemical Engineering, 11 Arany Janos, Postal code: 400028, Cluj-Napoca (Romania)

    2015-12-23

    This paper is evaluating two power generation concepts based on hydrogen produced from bioethanol steam reforming at industrial scale without and with carbon capture. The power generation from bioethanol conversion is based on two important steps: hydrogen production from bioethanol catalytic steam reforming and electricity generation using a hydrogen-fuelled gas turbine. As carbon capture method to be assessed in hydrogen-based power generation from bioethanol steam reforming, the gas-liquid absorption using methyl-di-ethanol-amine (MDEA) was used. Bioethanol is a renewable energy carrier mainly produced from biomass fermentation. Steam reforming of bioethanol (SRE) provides a promising method for hydrogen and power production from renewable resources. SRE is performed at high temperatures (e.g. 800-900°C) to reduce the reforming by-products (e.g. ethane, ethene). The power generation from hydrogen was done with M701G2 gas turbine (334 MW net power output). Hydrogen was obtained through catalytic steam reforming of bioethanol without and with carbon capture. For the evaluated plant concepts the following key performance indicators were assessed: fuel consumption, gross and net power outputs, net electrical efficiency, ancillary consumptions, carbon capture rate, specific CO{sub 2} emission etc. As the results show, the power generation based on bioethanol conversion has high energy efficiency and low carbon footprint.

  1. Hydrogen-based power generation from bioethanol steam reforming

    Science.gov (United States)

    Tasnadi-Asztalos, Zs.; Cormos, C. C.; Agachi, P. S.

    2015-12-01

    This paper is evaluating two power generation concepts based on hydrogen produced from bioethanol steam reforming at industrial scale without and with carbon capture. The power generation from bioethanol conversion is based on two important steps: hydrogen production from bioethanol catalytic steam reforming and electricity generation using a hydrogen-fuelled gas turbine. As carbon capture method to be assessed in hydrogen-based power generation from bioethanol steam reforming, the gas-liquid absorption using methyl-di-ethanol-amine (MDEA) was used. Bioethanol is a renewable energy carrier mainly produced from biomass fermentation. Steam reforming of bioethanol (SRE) provides a promising method for hydrogen and power production from renewable resources. SRE is performed at high temperatures (e.g. 800-900°C) to reduce the reforming by-products (e.g. ethane, ethene). The power generation from hydrogen was done with M701G2 gas turbine (334 MW net power output). Hydrogen was obtained through catalytic steam reforming of bioethanol without and with carbon capture. For the evaluated plant concepts the following key performance indicators were assessed: fuel consumption, gross and net power outputs, net electrical efficiency, ancillary consumptions, carbon capture rate, specific CO2 emission etc. As the results show, the power generation based on bioethanol conversion has high energy efficiency and low carbon footprint.

  2. Hydrogen-based power generation from bioethanol steam reforming

    International Nuclear Information System (INIS)

    This paper is evaluating two power generation concepts based on hydrogen produced from bioethanol steam reforming at industrial scale without and with carbon capture. The power generation from bioethanol conversion is based on two important steps: hydrogen production from bioethanol catalytic steam reforming and electricity generation using a hydrogen-fuelled gas turbine. As carbon capture method to be assessed in hydrogen-based power generation from bioethanol steam reforming, the gas-liquid absorption using methyl-di-ethanol-amine (MDEA) was used. Bioethanol is a renewable energy carrier mainly produced from biomass fermentation. Steam reforming of bioethanol (SRE) provides a promising method for hydrogen and power production from renewable resources. SRE is performed at high temperatures (e.g. 800-900°C) to reduce the reforming by-products (e.g. ethane, ethene). The power generation from hydrogen was done with M701G2 gas turbine (334 MW net power output). Hydrogen was obtained through catalytic steam reforming of bioethanol without and with carbon capture. For the evaluated plant concepts the following key performance indicators were assessed: fuel consumption, gross and net power outputs, net electrical efficiency, ancillary consumptions, carbon capture rate, specific CO2 emission etc. As the results show, the power generation based on bioethanol conversion has high energy efficiency and low carbon footprint

  3. Improvements of reforming performance of a nuclear heated steam reforming process

    International Nuclear Information System (INIS)

    Performance of an energy production process by utilizing high temperature nuclear process heat was not competitive to that by utilizing non-nuclear process heat, especially fossil-fired process heat due to its less favorable chemical reaction conditions. Less favorable conditions are because a temperature of the nuclear generated heat is around 950degC and the heat transferring fluid is the helium gas pressurized at around 4 MPa. Improvements of reforming performance of nuclear heated steam reforming process were proposed in the present report. The steam reforming process, one of hydrogen production processes, has the possibility to be industrialized as a nuclear heated process as early as expected, and technical solutions to resolve issues for coupling an HTGR with the steam reforming system are applicable to other nuclear-heated hydrogen production systems. The improvements are as follows: As for the steam reformer, (1) increase in heat input to process gas by applying a bayonet type of reformer tubes and so on, (2) increase in reforming temperature by enhancing heat transfer rate by the use of combined promoters of orifice baffles, cylindrical thermal radiation pipes and other proposal, and (3) increase in conversion rate of methane to hydrogen by optimizing chemical compositions of feed process gas. Regarding system arrangement, a steam generator and superheater are set in the helium loop as downstream coolers of the steam reformer, so as to effectively utilize the residual nuclear heat for generating feed steam. The improvements are estimated to achieve the hydrogen production rate of approximately 3800 STP-m3/h for the heat source of 10 MW and therefore will provide the potential competitiveness to a fossil-fired steam reforming process. Those improvements also provide the compactness of reformer tubes, giving the applicability of seamless tubes. (J.P.N.)

  4. A CFD approach on simulation of hydrogen production from steam reforming of glycerol in a fluidized bed reactor

    Energy Technology Data Exchange (ETDEWEB)

    Dou, Binlin; Song, Yongchen [School of Energy and Power Engineering, Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education, Dalian University of Technology, Dalian 116023 (China)

    2010-10-15

    Hydrogen production from steam reforming of glycerol in a fluidized bed reactor has been simulated using a CFD method by an additional transport equation with a kinetic term. The Eulerian-Eulerian two-fluid approach was adopted to simulate hydrodynamics of fluidization, and chemical reactions were modelled by laminar finite-rate model. The bed expansion and pressure drop were predicted for different inlet gas velocities. The results showed that the flow system exhibited a more heterogeneous structure, and the core-annulus structure of gas-solid flow led to back-mixing and internal circulation behaviour, and thus gave a poor velocity distribution. This suggests the bed should be agitated to maintain satisfactory fluidizing conditions. Glycerol conversion and H{sub 2} production were decreased with increasing inlet gas velocity. The increase in the value of steam to carbon molar ratio increases the conversion of glycerol and H{sub 2} selectivity. H{sub 2} concentrations in the bed were uneven and increased downstream and high concentrations of H{sub 2} production were also found on walls. The model demonstrated a relationship between hydrodynamics and hydrogen production, implying that the residence time and steam to carbon molar ratio are important parameters. The CFD simulation will provide helpful data to design and operate a bench scale catalytic fluidized bed reactor. (author)

  5. Produce synthesis gas by steam reforming natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Marsch, H.D.; Herbort, H.J.

    1982-06-01

    For production of synthesis gas from natural gas the steam reforming process is still the most economical. It generates synthesis gas for ammonia and methanol production as well as hydrogen, oxo gas and town gas. After desulfurization, the natural gas is mixed with steam and fed to the reforming furnace where decomposition of hydrocarbons takes place in the presence of a nickel-containing catalyst. Synthesis gas that must be free of CO and CO/sub 2/ is further treated in a CO shift conversion, a CO/sub 2/ scrubbing unit and a methanation unit. The discussion covers the following topics - reforming furnace; the outlet manifold system; secondary reformer; reformed gas cooling. Many design details of equipment used are given.

  6. Stabilization of Savannah River National Laboartory (SRNL) Aqueous Waste by Fluidized Bed Steam Reforming (FBSR)

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C

    2004-11-01

    The Savannah River National Laboratory (SRNL) is a multidisciplinary laboratory operated by Westinghouse Savannah River Company (WSRC) in Aiken, South Carolina. Research and development programs have been conducted at SRNL for {approx}50 years generating non-radioactive (hazardous and non-hazardous) and radioactive aqueous wastes. Typically the aqueous effluents from the R&D activities are disposed of from each laboratory module via the High Activity Drains (HAD) or the Low Activity Drains (LAD) depending on whether they are radioactive or not. The aqueous effluents are collected in holding tanks, analyzed and shipped to either H-Area (HAD waste) or the F/H Area Effluent Treatment Facility (ETF) (LAD waste) for volume reduction. Because collection, analysis, and transport of LAD and HAD waste is cumbersome and since future treatment of this waste may be curtailed as the F/H-Area evaporators and waste tanks are decommissioned, SRNL laboratory operations requested several proof of principle demonstrations of alternate technologies that would define an alternative disposal path for the aqueous wastes. Proof of principle for the disposal of SRNL HAD waste using a technology known as Fluidized Bed Steam Reforming (FBSR) is the focus of the current study. The FBSR technology can be performed either as a batch process, e.g. in each laboratory module in small furnaces with an 8'' by 8'' footprint, or in a semi-continuous Bench Scale Reformer (BSR). The proof of principle experiments described in this study cover the use of the FBSR technology at any scale (pilot or full scale). The proof of principle experiments described in this study used a non-radioactive HAD simulant.

  7. Kinetic Study of Nonequilibrium Plasma-Assisted Methane Steam Reforming

    OpenAIRE

    Hongtao Zheng; Qian Liu

    2014-01-01

    To develop a detailed reaction mechanism for plasma-assisted methane steam reforming, a comprehensive numerical and experimental study of effect laws on methane conversion and products yield is performed at different steam to methane molar ratio (S/C), residence time s, and reaction temperatures. A CHEMKIN-PRO software with sensitivity analysis module and path flux analysis module was used for simulations. A set of comparisons show that the developed reaction mechanism can accurately predict ...

  8. In silico search for novel methane steam reforming catalysts

    DEFF Research Database (Denmark)

    Xu, Yue; Lausche, Adam C; Wang, Shengguang;

    2013-01-01

    App’) with a microkinetic modeling technique to predict the rates and selectivities of a prospective material. This paper illustrates this screening technique using the steam reforming of methane to carbon monoxide and hydrogen as a test reaction. While catalysts are already commercially available for this...

  9. Steam Reforming of Low-Level Mixed Waste

    Energy Technology Data Exchange (ETDEWEB)

    None

    1998-01-01

    Under DOE Contract No. DE-AR21-95MC32091, Steam Reforming of Low-Level Mixed Waste, ThermoChem has successfully designed, fabricated and operated a nominal 90 pound per hour Process Development Unit (PDU) on various low-level mixed waste surrogates. The design construction, and testing of the PDU as well as performance and economic projections for a 500- lb/hr demonstration and commercial system are described. The overall system offers an environmentally safe, non-incinerating, cost-effective, and publicly acceptable method of processing LLMW. The steam-reforming technology was ranked the No. 1 non-incineration technology for destruction of hazardous organic wastes in a study commissioned by the Mixed Waste Focus Area published April 1997.1 The ThermoChem steam-reforming system has been developed over the last 13 years culminating in this successful test campaign on LLMW surrogates. Six surrogates were successfidly tested including a 750-hour test on material simulating a PCB- and Uranium- contaminated solid waste found at the Portsmouth Gaseous Diffusion Plant. The test results indicated essentially total (>99.9999oA) destruction of RCRA and TSCA hazardous halogenated organics, significant levels of volume reduction (> 400 to 1), and retention of radlonuclides in the volume-reduced solids. Cost studies have shown the steam-reforming system to be very cost competitive with more conventional and other emerging technologies.

  10. Optimizing a steam-methane reformer for hydrogen production

    NARCIS (Netherlands)

    Jong, de M.; Reinders, A.H.M.E.; Kok, J.B.W.; Westendorp, G.

    2009-01-01

    By means of steam reforming, natural gas is converted to carbon dioxide and hydrogen. The reactions take place in reactor tubes which are covered with catalyst at the inside, where the reactive mixture flows. At the outside they are heated by combustion of natural gas with air. In this paper the con

  11. Feasibility of a steam reforming plant heated by an HTGR

    International Nuclear Information System (INIS)

    The steam reforming of the methane using the heat from an H.T.G.R. has been studied to evaluate the feasibility of the process and the investment cost of the plant. The paper describes the main components of the plant in which each of the four intermediate heat exchangers integrated into the PCRV feeds one process train

  12. Optimizing the Heat Exchanger Network of a Steam Reforming System

    DEFF Research Database (Denmark)

    Nielsen, Mads Pagh; Korsgaard, Anders Risum; Kær, Søren Knudsen

    2004-01-01

    steam reforming reaction and steam must be generated. The dependence of the temperature profiles on conversion in shift reactors for gas purification is also significant. The optimum heat integration in the system is thus imperative in order to minimize the need for hot and cold utilities. A rigorous 1D......Proton Exchange Membrane (PEM) based combined heat and power production systems are highly integrated energy systems. They may include a hydrogen production system and fuel cell stacks along with post combustion units optionally coupled with gas turbines. The considered system is based on a natural...... gas steam reformer along with gas purification reactors to generate clean hydrogen suited for a PEM stack. The temperatures in the various reactors in the fuel processing system vary from around 1000°C to the stack temperature at 80°C. Furthermore, external heating must be supplied to the endothermic...

  13. Hydrogen Production with Steam Reforming of Dimethyl Ether

    Institute of Scientific and Technical Information of China (English)

    Kaoru TAKEISHI; Akane ARASE

    2005-01-01

    @@ 1Introduction Steam reforming of methanol and gasoline is actively researched and developed as hydrogen supply methods for the fuel cells of vehicles and so on. However, these materials have the problems such as the infrastructure, toxicity, difficulty of the reforming, and so forth. Dimethyl ether (DME) does not contain the poisonous substances, and is expected as a clean fuel of the next generation. DME is able to take the place of light oil and LPG, and its physical properties are similar to those of LPG. There is possibility that DME infrastructures will be settled more rapidly than those of hydrogen and methanol, because LPG infrastructures existing are able to use for DME. Then, we have been studying on steam reforming of DME for the hydrogen production.

  14. Kinetics of methanol steam reforming over COPZr-2 catalyst

    Institute of Scientific and Technical Information of China (English)

    Yongfeng Li; Weiming Lin; Lin Yu; Zhifeng Hao; Rongjian Mai

    2008-01-01

    The COPZr-2 catalyst, which was prepared in our prophase research, showed good catalytic performance in methanol steam reforming reaction. In this article, the best one was chosen as an example to study the reaction kinetics of methanol steam reforming over this type of catalyst. First, the effects of methanol conversion to outlet CO2 and methanol conversion to outlet CO on methanol pseudo contact time W/FMeOH were investigated. Then by applying the reaction route that methanol direct reforming (DR) and methanol decomposition (DE) were carried out in parallel, the reaction kinetic model with power function type was established. And the parameters for the model were estimated using a non-linear regression program which computed weighted least squares of the defined objects function. Finally, the kinetic model passed the correlation test and the F-test.

  15. Numerical analysis of steam reformer of steam methane reforming hydrogen production system connected with high temperature gas cooled reactor

    International Nuclear Information System (INIS)

    In order to quantitatively analyze the performance of the helium-heated reformer used in steam methane reforming hydrogen production system connected with high temperature gas cooled reactor, a dynamic model has been set up based on one-dimension quasi-homogeneous phase model. And a computer program is development. Model verification is performed under steady state using test results of Japan Atomic Energy Institute. The steady state calculation results fit well with the experiment results. Reaction velocity is not the main factor influencing the performance. Reformer tube with finned central tube improves the performance remarkably comparing with smooth central tube. (authors)

  16. Application of Flexible Micro Temperature Sensor in Oxidative Steam Reforming by a Methanol Micro Reformer

    Directory of Open Access Journals (Sweden)

    Yi-Man Lo

    2011-02-01

    Full Text Available Advances in fuel cell applications reflect the ability of reformers to produce hydrogen. This work presents a flexible micro temperature sensor that is fabricated based on micro-electro-mechanical systems (MEMS technology and integrated into a flat micro methanol reformer to observe the conditions inside that reformer. The micro temperature sensor has higher accuracy and sensitivity than a conventionally adopted thermocouple. Despite various micro temperature sensor applications, integrated micro reformers are still relatively new. This work proposes a novel method for integrating micro methanol reformers and micro temperature sensors, subsequently increasing the methanol conversion rate and the hydrogen production rate by varying the fuel supply rate and the water/methanol ratio. Importantly, the proposed micro temperature sensor adequately controls the interior temperature during oxidative steam reforming of methanol (OSRM, with the relevant parameters optimized as well.

  17. Effect of Cobalt Particle Size on Acetone Steam Reforming

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Junming; Zhang, He; Yu, Ning; Davidson, Stephen D.; Wang, Yong

    2015-06-11

    Carbon-supported cobalt nanoparticles with different particle sizes were synthesized and characterized by complementary characterization techniques such as X-ray diffraction, N-2 sorption, acetone temperature-programmed desorption, transmission electron microscopy, and CO chemisorption. Using acetone steam reforming reaction as a probe reaction, we revealed a volcano-shape curve of the intrinsic activity (turnover frequency of acetone) and the CO2 selectivity as a function of the cobalt particle size with the highest activity and selectivity observed at a particle size of approximately 12.8nm. Our results indicate that the overall performance of acetone steam reforming is related to a combination of particle-size-dependent acetone decomposition, water dissociation, and the oxidation state of the cobalt nanoparticles.

  18. Design of a surface alloy catalyst for steam reforming

    DEFF Research Database (Denmark)

    Besenbacher, F.; Chorkendorff, Ib; Clausen, B.S.;

    1998-01-01

    Detailed studies of elementary chemical processes on well-characterized single crystal surfaces have contributed substantially to the understanding of heterogeneous catalysis. insight into the structure of surface alloys combined with an understanding of the relation between the surface composition...... and reactivity is shown to lead directly to new ideas for catalyst design, The feasibility of such an approach is illustrated by the synthesis, characterization, and tests of a high-surface area gold-nickel catalyst for steam reforming....

  19. Steam Methane Reforming System for Hydrogen Production: Advanced Exergetic Analysis

    OpenAIRE

    Morosuk, Tatiana; Boyano, Alicia; Blanco-Marigorta, Ana-Maria; Tsatsaronis, George

    2012-01-01

    Steam methane reforming (SMR) is one of the most promising processes for the production of hydrogen. Therefore, the overall thermodynamic efficiency of this process is of particular importance. The thermodynamic inefficiencies in a thermal system are related to exergy destruction and exergy loss. However, a conventional exergetic analysis cannot evaluate the mutual interdependencies among the system components nor the real potential for improving the energy conversion system being considered....

  20. In silico search for novel methane steam reforming catalysts

    OpenAIRE

    Xu, Yue; Lausche, Adam C; Wang, Shengguang; Khan, Tuhin Suvra; Abild-Pedersen, Frank; Studt, Felix; Nørskov, Jens K.; Bligaard, Thomas

    2013-01-01

    This paper demonstrates a method for screening transition metal and metal alloy catalysts based on their predicted rates and stabilities for a given catalytic reaction. This method involves combining reaction and activation energies (available to the public via a web-based application ‘CatApp’) with a microkinetic modeling technique to predict the rates and selectivities of a prospective material. This paper illustrates this screening technique using the steam reforming of methane to carbon m...

  1. Thermoelectric generation coupling methanol steam reforming characteristic in microreactor

    International Nuclear Information System (INIS)

    Thermoelectric (TE) generator converts heat to electric energy by thermoelectric material. However, heat removal on the cold side of the generator represents a serious challenge. To address this problem and for improved energy conversion, a thermoelectric generation process coupled with methanol steam reforming (SR) for hydrogen production is designed and analyzed in this paper. Experimental study on the cold spot character in a micro-reactor with monolayer catalyst bed is first carried out to understand the endothermic nature of the reforming as the thermoelectric cold side. A novel methanol steam reforming micro-reactor heated by waste heat or methanol catalytic combustion for hydrogen production coupled with a thermoelectric generation module is then simulated. Results show that the cold spot effect exists in the catalyst bed under all conditions, and the associated temperature difference first increases and then decreases with the inlet temperature. In the micro-reactor, the temperature difference between the reforming and heating channel outlets decreases rapidly with an increase in thermoelectric material's conductivity coefficient. However, methanol conversion at the reforming outlet is mainly affected by the reactor inlet temperature; while at the combustion outlet, it is mainly affected by the reactor inlet velocity. Due to the strong endothermic effect of the methanol steam reforming, heat supply of both kinds cannot balance the heat needed at reactor local areas, resulting in the cold spot at the reactor inlet. When the temperature difference between the thermoelectric module's hot and cold sides is 22 K, the generator can achieve an output voltage of 55 mV. The corresponding molar fraction of hydrogen can reach about 62.6%, which corresponds to methanol conversion rate of 72.6%. - Highlights: • Cold spot character of methanol steam reforming was studied through experiment. • Thermoelectric generation Coupling MSR process has been

  2. Steam reforming of low-level mixed waste. Final report

    International Nuclear Information System (INIS)

    ThermoChem has successfully designed, fabricated and operated a nominal 90 pound per hour Process Development Unit (PDU) on various low-level mixed waste surrogates. The design, construction, and testing of the PDU as well as performance and economic projections for a 300-lb/hr demonstration and commercial system are described. The overall system offers an environmentally safe, non-incinerating, cost-effective, and publicly acceptable method of processing LLMW. The steam-reforming technology was ranked the No. 1 non-incineration technology for destruction of hazardous organic wastes in a study commissioned by the Mixed Waste Focus Area and published in April 1997. The ThermoChem steam-reforming system has been developed over the last 13 years culminating in this successful test campaign on LLMW surrogates. Six surrogates were successfully tested including a 750-hour test on material simulating a PCB- and Uranium-contaminated solid waste found at the Portsmouth Gaseous Diffusion Plant. The test results indicated essentially total (> 99.9999%) destruction of RCRA and TSCA hazardous halogenated organics, significant levels of volume reduction (> 400 to 1), and retention of radionuclides in the volume-reduced solids. Economic evaluations have shown the steam-reforming system to be very cost competitive with more conventional and other emerging technologies

  3. Hydrogen production by sorption-enhanced steam reforming of glycerol.

    Science.gov (United States)

    Dou, Binlin; Dupont, Valerie; Rickett, Gavin; Blakeman, Neil; Williams, Paul T; Chen, Haisheng; Ding, Yulong; Ghadiri, Mojtaba

    2009-07-01

    Catalytic steam reforming of glycerol for H(2) production has been evaluated experimentally in a continuous flow fixed-bed reactor. The experiments were carried out under atmospheric pressure within a temperature range of 400-700 degrees C. A commercial Ni-based catalyst and a dolomite sorbent were used for the steam reforming reactions and in situ CO(2) removal. The product gases were measured by on-line gas analysers. The results show that H(2) productivity is greatly increased with increasing temperature and the formation of methane by-product becomes negligible above 500 degrees C. The results suggest an optimal temperature of approximately 500 degrees C for the glycerol steam reforming with in situ CO(2) removal using calcined dolomite as the sorbent, at which the CO(2) breakthrough time is longest and the H(2) purity is highest. The shrinking core model and the 1D-diffusion model describe well the CO(2) removal under the conditions of this work. PMID:19318245

  4. Development and test evaluation of duplex steam reformer tube

    International Nuclear Information System (INIS)

    For HTR applications involving a steam reformer (SR), it is uncertain whether an intermediate heat exchanger (IHX) is required. There are several system configurations that could be developed for the application of nuclear heat using the steam reformer reaction. The considerations (advantages vs. disadvantages) for each of the system configurations are summarized. The approach that technically and economically appears to be the most attractive, in studies conducted by General Electric, combines the SR process heat exchanger and the IHX in a single component using a duplex tube. A central question concerning the duplex tube concept is whether the design would provide adequate leak monitoring capability and significant reduction in tritium and hydrogen diffusion, while introducing only a small increase in overall temperature difference from the helium to the process gas. A cooperative GE-KFA effort was undertaken to develop, fabricate, test, and evaluate a duplex steam reformer tube. GE was responsible for the development and fabrication of the tube, and KFA was responsible for testing the tube in the EVA I facility at Juelich. Both GE and KFA are evaluating the thermochemical and metallurgical test data. Actual fabrication of the tube was performed by Foster-Wheeler in accordance with the GE design. This paper reviews the highlights of the fabrication development and preliminary evaluation of the test data

  5. Steam reforming of low-level mixed waste. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-06-01

    ThermoChem has successfully designed, fabricated and operated a nominal 90 pound per hour Process Development Unit (PDU) on various low-level mixed waste surrogates. The design, construction, and testing of the PDU as well as performance and economic projections for a 300-lb/hr demonstration and commercial system are described. The overall system offers an environmentally safe, non-incinerating, cost-effective, and publicly acceptable method of processing LLMW. The steam-reforming technology was ranked the No. 1 non-incineration technology for destruction of hazardous organic wastes in a study commissioned by the Mixed Waste Focus Area and published in April 1997. The ThermoChem steam-reforming system has been developed over the last 13 years culminating in this successful test campaign on LLMW surrogates. Six surrogates were successfully tested including a 750-hour test on material simulating a PCB- and Uranium-contaminated solid waste found at the Portsmouth Gaseous Diffusion Plant. The test results indicated essentially total (> 99.9999%) destruction of RCRA and TSCA hazardous halogenated organics, significant levels of volume reduction (> 400 to 1), and retention of radionuclides in the volume-reduced solids. Economic evaluations have shown the steam-reforming system to be very cost competitive with more conventional and other emerging technologies.

  6. Novel zeolite-supported rhodium catalysts for ethanol steam reforming

    Science.gov (United States)

    Campos-Skrobot, Fabiana C.; Rizzo-Domingues, Roberta C. P.; Fernandes-Machado, Nádia R. C.; Cantão, Mauricio P.

    Renewable bioethanol is an interesting hydrogen source for fuel cells through steam reforming, but its C-C bond promotes parallel reactions, mainly coke and by-products formation. In this way, good ethanol reforming catalysts are still needed, which explains current research and development efforts around the world. Most catalysts proposed for ethanol reforming are based on oxide-supported noble metals with surface area below 100 m 2 g -1 and reaction temperatures above 500 °C. Novel Rh and Rh-K catalysts supported on NaY zeolite with surface area above 440 m 2 g -1 are presented in this work. Reaction temperature was fixed at 300 °C and H 2O/EtOH molar ratio and reagent flow were varied. Ethanol conversion varied from 50 to 99%, with average increase of 50% due to K promoter, and hydrogen production yield achieved 68%.

  7. Thermodynamic analysis of carbon formation boundary and reforming performance for steam reforming of dimethyl ether

    Science.gov (United States)

    Faungnawakij, Kajornsak; Kikuchi, Ryuji; Eguchi, Koichi

    Thermodynamic analysis of dimethyl ether steam reforming (DME SR) was investigated for carbon formation boundary, DME conversion, and hydrogen yield for fuel cell application. The equilibrium calculation employing Gibbs free minimization was performed to figure out the required steam-to-carbon ratio (S/C = 0-5) and reforming temperature (25-1000 °C) where coke formation was thermodynamically unfavorable. S/C, reforming temperature and product species strongly contributed to the coke formation and product composition. When chemical species DME, methanol, CO 2, CO, H 2, H 2O and coke were considered, complete conversion of DME and hydrogen yield above 78% without coke formation were achieved at the normal operating temperatures of molten carbonate fuel cell (600 °C) and solid oxide fuel cell (900 °C), when S/C was at or above 2.5. When CH 4 was favorable, production of coke and that of hydrogen were significantly suppressed.

  8. Bench-Scale Silicone Process for Low-Cost CO{sub 2} Capture

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Benjamin; Genovese, Sarah; Perry, Robert; Spiry, Irina; Farnum, Rachael; Sing, Surinder; Wilson, Paul; Buckley, Paul; Acharya, Harish; Chen, Wei; McDermott, John; Vipperia, Ravikumar; Yee, Michael; Steele, Ray; Fresia, Megan; Vogt, Kirk

    2013-12-31

    A bench-scale system was designed and built to test an aminosilicone-based solvent. A model was built of the bench-scale system and this model was scaled up to model the performance of a carbon capture unit, using aminosilicones, for CO{sub 2} capture and sequestration (CCS) for a pulverized coal (PC) boiler at 550 MW. System and economic analysis for the carbon capture unit demonstrates that the aminosilicone solvent has significant advantages relative to a monoethanol amine (MEA)-based system. The CCS energy penalty for MEA is 35.9% and the energy penalty for aminosilicone solvent is 30.4% using a steam temperature of 395 °C (743 °F). If the steam temperature is lowered to 204 °C (400 °F), the energy penalty for the aminosilicone solvent is reduced to 29%. The increase in cost of electricity (COE) over the non-capture case for MEA is ~109% and increase in COE for aminosilicone solvent is ~98 to 103% depending on the solvent cost at a steam temperature of 395 °C (743 °F). If the steam temperature is lowered to 204 °C (400 °F), the increase in COE for the aminosilicone solvent is reduced to ~95-100%.

  9. Methane-steam reforming by molten salt - membrane reactor using concentrated solar thermal energy

    International Nuclear Information System (INIS)

    By utilization of concentrated solar thermal energy for steam reforming of natural gas, which is an endothermic reaction, the chemical energy of natural gas can be up-graded. The chemical system for steam reforming of natural gas with concentrated solar thermal energy was studied to produce hydrogen by using the thermal storage with molten salt and the membrane reactor. The original steam reforming module with hydrogen permeable palladium membrane was developed and fabricated. Steam reforming of methane proceeded with the original module with palladium membrane below the decomposition temperature of molten salt (around 870 K). (authors)

  10. Thermodynamic evaluation of hydrogen production via bioethanol steam reforming

    Energy Technology Data Exchange (ETDEWEB)

    Tasnadi-Asztalos, Zsolt; Cormos, Ana-Maria; Imre-Lucaci, Árpád; Cormos, Călin C. [Babes-Bolyai University, Faculty of Chemistry and Chemical Engineering, Arany Janos 11, RO-400028, Cluj-Napoca (Romania)

    2013-11-13

    In this article, a thermodynamic analysis for bioethanol steam reforming for hydrogen production is presented. Bioethanol is a newly proposed renewable energy carrier mainly produced from biomass fermentation. Reforming of bioethanol provides a promising method for hydrogen production from renewable resources. Steam reforming of ethanol (SRE) takes place under the action of a metal catalyst capable of breaking C-C bonds into smaller molecules. A large domain for the water/bioethanol molar ratio as well as the temperature and average pressure has been used in the present work. The interval of investigated temperature was 100-800°C, the pressure was in the range of 1-10 bar and the molar ratio was between 3-25. The variations of gaseous species concentration e.g. H{sub 2}, CO, CO{sub 2}, CH{sub 4} were analyzed. The concentrations of the main products (H{sub 2} and CO) at lower temperature are smaller than the ones at higher temperature due to by-products formation (methane, carbon dioxide, acetylene etc.). The concentration of H2 obtained in the process using high molar ratio (>20) is higher than the one at small molar ratio (near stoichiometric). When the pressure is increased the hydrogen concentration decreases. The results were compared with literature data for validation purposes.

  11. Thermodynamic evaluation of hydrogen production via bioethanol steam reforming

    Science.gov (United States)

    Tasnadi-Asztalos, Zsolt; Cormos, Ana-Maria; Imre-Lucaci, Árpád; Cormos, Cǎlin C.

    2013-11-01

    In this article, a thermodynamic analysis for bioethanol steam reforming for hydrogen production is presented. Bioethanol is a newly proposed renewable energy carrier mainly produced from biomass fermentation. Reforming of bioethanol provides a promising method for hydrogen production from renewable resources. Steam reforming of ethanol (SRE) takes place under the action of a metal catalyst capable of breaking C-C bonds into smaller molecules. A large domain for the water/bioethanol molar ratio as well as the temperature and average pressure has been used in the present work. The interval of investigated temperature was 100-800°C, the pressure was in the range of 1-10 bar and the molar ratio was between 3-25. The variations of gaseous species concentration e.g. H2, CO, CO2, CH4 were analyzed. The concentrations of the main products (H2 and CO) at lower temperature are smaller than the ones at higher temperature due to by-products formation (methane, carbon dioxide, acetylene etc.). The concentration of H2 obtained in the process using high molar ratio (>20) is higher than the one at small molar ratio (near stoichiometric). When the pressure is increased the hydrogen concentration decreases. The results were compared with literature data for validation purposes.

  12. Thermodynamic evaluation of hydrogen production via bioethanol steam reforming

    International Nuclear Information System (INIS)

    In this article, a thermodynamic analysis for bioethanol steam reforming for hydrogen production is presented. Bioethanol is a newly proposed renewable energy carrier mainly produced from biomass fermentation. Reforming of bioethanol provides a promising method for hydrogen production from renewable resources. Steam reforming of ethanol (SRE) takes place under the action of a metal catalyst capable of breaking C-C bonds into smaller molecules. A large domain for the water/bioethanol molar ratio as well as the temperature and average pressure has been used in the present work. The interval of investigated temperature was 100-800°C, the pressure was in the range of 1-10 bar and the molar ratio was between 3-25. The variations of gaseous species concentration e.g. H2, CO, CO2, CH4 were analyzed. The concentrations of the main products (H2 and CO) at lower temperature are smaller than the ones at higher temperature due to by-products formation (methane, carbon dioxide, acetylene etc.). The concentration of H2 obtained in the process using high molar ratio (>20) is higher than the one at small molar ratio (near stoichiometric). When the pressure is increased the hydrogen concentration decreases. The results were compared with literature data for validation purposes

  13. 2009 PILOT SCALE FLUIDIZED BED STEAM REFORMING TESTING USING THE THOR (THERMAL ORGANIC REDUCTION) PROCESS: ANALYTICAL RESULTS FOR TANK 48H ORGANIC DESTRUCTION - 10408

    International Nuclear Information System (INIS)

    The Savannah River Site (SRS) must empty the contents of Tank 48H, a 1.3 million gallon Type IIIA HLW storage tank, to return this tank to service. The tank contains organic compounds, mainly potassium tetraphenylborate that cannot be processed downstream until the organic components are destroyed. The THOR(regsign) Treatment Technologies (TTT) Fluidized Bed Steam Reforming (FBSR) technology, herein after referred to as steam reforming, has been demonstrated to be a viable process to remove greater than 99.9% of the organics from Tank 48H during various bench scale and pilot scale tests. These demonstrations were supported by Savannah River Remediation (SRR) and the Department of Energy (DOE) has concurred with the SRR recommendation to proceed with the deployment of the FBSR technology to treat the contents of Tank 48H. The Savannah River National Laboratory (SRNL) developed and proved the concept with non-radioactive simulants for SRR beginning in 2003. By 2008, several pilot scale campaigns had been completed and extensive crucible testing and bench scale testing were performed in the SRNL Shielded Cells using Tank 48H radioactive sample. SRNL developed a Tank 48H non-radioactive simulant complete with organic compounds, salt, and metals characteristic of those measured in a sample of the radioactive contents of Tank 48H. FBSR Pilot Scaled Testing with the Tank 48H simulant has demonstrated the ability to remove greater than 98% of the nitrites and greater than 99.5% of the nitrates from the Tank 48H simulant, and to form a solid product that is primarily alkali carbonate. The alkali carbonate is soluble and, thus, amenable to pumping as a liquid to downstream facilities for processing. The FBSR technology was demonstrated in October of 2006 in the Engineering Scale Test Demonstration (ESTD) pilot scale steam reformer at the Hazen Research Inc. (HRI) facility in Golden, CO. Additional ESTD tests were completed in 2008 and in 2009 that further demonstrated the

  14. 2009 PILOT SCALE FLUIDIZED BED STEAM REFORMING TESTING USING THE THOR (THERMAL ORGANIC REDUCTION) PROCESS: ANALYTICAL RESULTS FOR TANK 48H ORGANIC DESTRUCTION - 10408

    Energy Technology Data Exchange (ETDEWEB)

    Williams, M.; Jantzen, C.; Burket, P.; Crawford, C.; Daniel, G.; Aponte, C.; Johnson, C.

    2009-12-28

    The Savannah River Site (SRS) must empty the contents of Tank 48H, a 1.3 million gallon Type IIIA HLW storage tank, to return this tank to service. The tank contains organic compounds, mainly potassium tetraphenylborate that cannot be processed downstream until the organic components are destroyed. The THOR{reg_sign} Treatment Technologies (TTT) Fluidized Bed Steam Reforming (FBSR) technology, herein after referred to as steam reforming, has been demonstrated to be a viable process to remove greater than 99.9% of the organics from Tank 48H during various bench scale and pilot scale tests. These demonstrations were supported by Savannah River Remediation (SRR) and the Department of Energy (DOE) has concurred with the SRR recommendation to proceed with the deployment of the FBSR technology to treat the contents of Tank 48H. The Savannah River National Laboratory (SRNL) developed and proved the concept with non-radioactive simulants for SRR beginning in 2003. By 2008, several pilot scale campaigns had been completed and extensive crucible testing and bench scale testing were performed in the SRNL Shielded Cells using Tank 48H radioactive sample. SRNL developed a Tank 48H non-radioactive simulant complete with organic compounds, salt, and metals characteristic of those measured in a sample of the radioactive contents of Tank 48H. FBSR Pilot Scaled Testing with the Tank 48H simulant has demonstrated the ability to remove greater than 98% of the nitrites and greater than 99.5% of the nitrates from the Tank 48H simulant, and to form a solid product that is primarily alkali carbonate. The alkali carbonate is soluble and, thus, amenable to pumping as a liquid to downstream facilities for processing. The FBSR technology was demonstrated in October of 2006 in the Engineering Scale Test Demonstration (ESTD) pilot scale steam reformer at the Hazen Research Inc. (HRI) facility in Golden, CO. Additional ESTD tests were completed in 2008 and in 2009 that further demonstrated the

  15. Modified Ni-Cu catalysts for ethanol steam reforming

    International Nuclear Information System (INIS)

    Three Ni-Cu catalysts, having different Cu content, supported on γ-alumina were synthesized by wet co-impregnation method, characterized and tested in the ethanol steam reforming (ESR) reaction. The catalysts were characterized for determination of: total surface area and porosity (N2 adsorption - desorption using BET and Dollimer Heal methods), Ni surface area (hydrogen chemisorption), crystallinity and Ni crystallites size (X-Ray Diffraction), type of catalytic active centers (Hydrogen Temperature Programmed Reduction). Total surface area and Ni crystallites size are not significantly influenced by the addition of Cu, while Ni surface area is drastically diminished by increasing of Cu concentration. Steam reforming experiments were performed at atmospheric pressure, temperature range 150-350°C, and ethanol - water molar ration of 1 at 30, using Ar as carrier gas. Ethanol conversion and hydrogen production increase by the addition of Cu. At 350°C there is a direct connection between hydrogen production and Cu concentration. Catalysts deactivation in 24h time on stream was studied by Transmission Electron Microscopy (TEM) and temperature-programmed reduction (TPR) on used catalysts. Coke deposition was observed at all studied temperatures; at 150°C amorphous carbon was evidenced, while at 350°C crystalline, filamentous carbon is formed

  16. Kinetic Study of Nonequilibrium Plasma-Assisted Methane Steam Reforming

    Directory of Open Access Journals (Sweden)

    Hongtao Zheng

    2014-01-01

    Full Text Available To develop a detailed reaction mechanism for plasma-assisted methane steam reforming, a comprehensive numerical and experimental study of effect laws on methane conversion and products yield is performed at different steam to methane molar ratio (S/C, residence time s, and reaction temperatures. A CHEMKIN-PRO software with sensitivity analysis module and path flux analysis module was used for simulations. A set of comparisons show that the developed reaction mechanism can accurately predict methane conversion and the trend of products yield in different operating conditions. Using the developed reaction mechanism in plasma-assisted kinetic model, the reaction path flux analysis was carried out. The result shows that CH3 recombination is the limiting reaction for CO production and O is the critical species for CO production. Adding 40 wt.% Ni/SiO2 in discharge region has significantly promoted the yield of H2, CO, or CO2 in dielectric packed bed (DPB reactor. Plasma catalytic hybrid reforming experiment verifies the reaction path flux analysis tentatively.

  17. Ni Catalysts Supported on Modified Alumina for Diesel Steam Reforming

    Directory of Open Access Journals (Sweden)

    Antonios Tribalis

    2016-01-01

    Full Text Available Nickel catalysts are the most popular for steam reforming, however, they have a number of drawbacks, such as high propensity toward coke formation and intolerance to sulfur. In an effort to improve their behavior, a series of Ni-catalysts supported on pure and La-, Ba-, (La+Ba- and Ce-doped γ-alumina has been prepared. The doped supports and the catalysts have been extensively characterized. The catalysts performance was evaluated for steam reforming of n-hexadecane pure or doped with dibenzothiophene as surrogate for sulphur-free or commercial diesel, respectively. The undoped catalyst lost its activity after 1.5 h on stream. Doping of the support with La improved the initial catalyst activity. However, this catalyst was completely deactivated after 2 h on stream. Doping with Ba or La+Ba improved the stability of the catalysts. This improvement is attributed to the increase of the dispersion of the nickel phase, the decrease of the support acidity and the increase of Ni-phase reducibility. The best catalyst of the series doped with La+Ba proved to be sulphur tolerant and stable for more than 160 h on stream. Doping of the support with Ce also improved the catalytic performance of the corresponding catalyst, but more work is needed to explain this behavior.

  18. Modified Ni-Cu catalysts for ethanol steam reforming

    Energy Technology Data Exchange (ETDEWEB)

    Dan, M.; Mihet, M.; Almasan, V.; Borodi, G. [National Institute for Research and Development of Isotopic and Molecular Technologies, 65-103 Donath Street, 400293, Cluj-Napoca (Romania); Katona, G.; Muresan, L. [Univ. Babes Bolyai, Fac. Chem. and Chem. Eng.,11 Arany Janos, 400028, Cluj-Napoca (Romania); Lazar, M. D., E-mail: diana.lazar@itim-cj.ro [65-103 Donath Street (Romania)

    2013-11-13

    Three Ni-Cu catalysts, having different Cu content, supported on γ-alumina were synthesized by wet co-impregnation method, characterized and tested in the ethanol steam reforming (ESR) reaction. The catalysts were characterized for determination of: total surface area and porosity (N{sub 2} adsorption - desorption using BET and Dollimer Heal methods), Ni surface area (hydrogen chemisorption), crystallinity and Ni crystallites size (X-Ray Diffraction), type of catalytic active centers (Hydrogen Temperature Programmed Reduction). Total surface area and Ni crystallites size are not significantly influenced by the addition of Cu, while Ni surface area is drastically diminished by increasing of Cu concentration. Steam reforming experiments were performed at atmospheric pressure, temperature range 150-350°C, and ethanol - water molar ration of 1 at 30, using Ar as carrier gas. Ethanol conversion and hydrogen production increase by the addition of Cu. At 350°C there is a direct connection between hydrogen production and Cu concentration. Catalysts deactivation in 24h time on stream was studied by Transmission Electron Microscopy (TEM) and temperature-programmed reduction (TPR) on used catalysts. Coke deposition was observed at all studied temperatures; at 150°C amorphous carbon was evidenced, while at 350°C crystalline, filamentous carbon is formed.

  19. Kinetics of methane steam reforming over Ni/Ce-ZrO2

    International Nuclear Information System (INIS)

    'Full text:' This paper investigates the steam reforming of methane over Ni catalyst on Ce-ZrO2 support with different Ce/Zr ratios. Firstly, the pretreatment conditions of each catalyst were investigated in order to provide the best performance toward methane steam reforming. Ni/Ce- ZrO2 with the Ce/Zr ratio of 3/1 showed the best performance in terms of activity and stability. Essential kinetic information for this catalyst was determined. The reaction order in methane was always 1. The catalyst showed a positive effect of hydrogen and a negative effect of steam on the methane steam reforming reactivity. The negative effect of steam became weaker with increasing hydrogen partial pressure and temperature, whereas the positive effect of hydrogen became slightly stronger with increasing steam partial pressure but seemed to be independent of temperature. Addition of carbon monoxide promoted the conversion of methane, whereas addition of carbon dioxide inhibited the reforming rate. Methane steam reforming mechanism proposed by Boudart et al. (1972) can be applied to explain the experimental results for the steam reforming of methane over Ni/Ce-ZrO2. In addition, the experimental data can be well fitted to the methane steam reforming rate equation reported by Dick et al. (2000). (author)

  20. Development and validation of a CFD-based steam reformer model

    DEFF Research Database (Denmark)

    Kær, Søren Knudsen; Dahlqvist, Mathis; Saksager, Anders;

    2006-01-01

    Steam reforming of liquid biofuels (ethanol, bio-diesel etc.) represents a sustainable source of hydrogen for micro Combined Heat and Power (CHP) production as well as Auxiliary Power Units (APUs). In relation to the design of the steam reforming reactor several parameter are important including...

  1. Alcohols and bio-alcohols steam and autothermal reforming in a membrane reactor

    OpenAIRE

    Llorca Piqué, Jordi; Hedayati, Ali

    2014-01-01

    Considerable work has been reported concerning catalytic steam reforming, partial oxidation and oxidative steam reforming (autothermal reforming) aimed at hydrogen generation from alcohol-water mixtures. They include methanol, ethanol, glycerol, and the exploitiation of renewable bio-alcohols. The use of catalytic membrane reactors, with simultaneous generation and separation of hydrogen, appears as an attractive approach to optimize downstream separation and to substantially simplify on-site...

  2. Influence of Steam Reforming Catalyst Geometry on the Performance of Tubular Reformer – Simulation Calculations

    Directory of Open Access Journals (Sweden)

    Franczyk Ewelina

    2015-06-01

    Full Text Available A proper selection of steam reforming catalyst geometry has a direct effect on the efficiency and economy of hydrogen production from natural gas and is a very important technological and engineering issue in terms of process optimisation. This paper determines the influence of widely used seven-hole grain diameter (ranging from 11 to 21 mm, h/d (height/diameter ratio of catalyst grain and Sh/St (hole surface/total cylinder surface in cross-section ratio (ranging from 0.13 to 0.37 on the gas load of catalyst bed, gas flow resistance, maximum wall temperature and the risk of catalyst coking. Calculations were based on the one-dimensional pseudo-homogeneous model of a steam reforming tubular reactor, with catalyst parameters derived from our investigations. The process analysis shows that it is advantageous, along the whole reformer tube length, to apply catalyst forms of h/d = 1 ratio, relatively large dimensions, possibly high bed porosity and Sh/St ≈ 0.30-0.37 ratio. It enables a considerable process intensification and the processing of more natural gas at the same flow resistance, despite lower bed activity, without catalyst coking risk. Alternatively, plant pressure drop can be reduced maintaining the same gas load, which translates directly into diminishing the operating costs as a result of lowering power consumption for gas compression.

  3. Catalytic deactivation on methane steam reforming catalysts. 2. Kinetic study

    Energy Technology Data Exchange (ETDEWEB)

    Agnelli, M.E.; Ponzi, E.N.; Yeramian, A.A.

    1987-08-01

    The kinetics of methane steam reforming reaction over an alumina-supported nickel catalyst was investigated at a temperature range of 640-740/sup 0/C in a flow reactor at atmospheric pressure. The experiments were performed varying the inlet concentration of methane, hydrogen, and water. A kinetic scheme of the Houghen-Watson type was satisfactorily proposed assuming the dissociative adsorption of CH/sub 4/ as the rate-limiting step, but this kinetic scheme can be easily replaced by a first-order kinetics (r/sub CH/4/sub / = kapparho/sub CH/4/sub /) for engineering purposes. Catalyst activation with H/sub 2/ and N/sub 2/ mixtures or with the reactant mixture results in the same extent of reaction.

  4. In silico search for novel methane steam reforming catalysts

    Science.gov (United States)

    Xu, Yue; Lausche, Adam C.; Wang, Shengguang; Khan, Tuhin S.; Abild-Pedersen, Frank; Studt, Felix; Nørskov, Jens K.; Bligaard, Thomas

    2013-12-01

    This paper demonstrates a method for screening transition metal and metal alloy catalysts based on their predicted rates and stabilities for a given catalytic reaction. This method involves combining reaction and activation energies (available to the public via a web-based application ‘CatApp’) with a microkinetic modeling technique to predict the rates and selectivities of a prospective material. This paper illustrates this screening technique using the steam reforming of methane to carbon monoxide and hydrogen as a test reaction. While catalysts are already commercially available for this process, the method demonstrated in this paper is very general and could be applied to a wide range of catalytic reactions. Following the steps outlined herein, such an analysis could potentially enable researchers to understand reaction mechanisms on a fundamental level and, on this basis, develop leads for new metal alloy catalysts.

  5. In silico search for novel methane steam reforming catalysts

    International Nuclear Information System (INIS)

    This paper demonstrates a method for screening transition metal and metal alloy catalysts based on their predicted rates and stabilities for a given catalytic reaction. This method involves combining reaction and activation energies (available to the public via a web-based application ‘CatApp’) with a microkinetic modeling technique to predict the rates and selectivities of a prospective material. This paper illustrates this screening technique using the steam reforming of methane to carbon monoxide and hydrogen as a test reaction. While catalysts are already commercially available for this process, the method demonstrated in this paper is very general and could be applied to a wide range of catalytic reactions. Following the steps outlined herein, such an analysis could potentially enable researchers to understand reaction mechanisms on a fundamental level and, on this basis, develop leads for new metal alloy catalysts. (paper)

  6. Steam Methane Reforming System for Hydrogen Production: Advanced Exergetic Analysis

    Directory of Open Access Journals (Sweden)

    Tatiana Morosuk

    2012-02-01

    Full Text Available Steam methane reforming (SMR is one of the most promising processes for the production of hydrogen. Therefore, the overall thermodynamic efficiency of this process is of particular importance. The thermodynamic inefficiencies in a thermal system are related to exergy destruction and exergy loss. However, a conventional exergetic analysis cannot evaluate the mutual interdependencies among the system components nor the real potential for improving the energy conversion system being considered. One of the tools under development for the improvement of energy conversion systems from the thermodynamic viewpoint is the advanced exergetic analysis. In this paper, the avoidable part of the exergy destruction is estimated and the interactions among components of the overall system are evaluated in terms of endogenous and exogenous exergy destruction. The assumptions required for these calculations are discussed in detail, especially for those components that are typically used in chemical processes. Results of this paper suggest options for increasing the thermodynamic efficiency of hydrogen production by steam-methane reforming.

  7. Influence of Steam Reforming Catalyst Geometry on the Performance of Tubular Reformer – Simulation Calculations

    OpenAIRE

    Franczyk Ewelina; Gołębiowski Andrzej; Borowiecki Tadeusz; Kowalik Paweł; Wróbel Waldemar

    2015-01-01

    A proper selection of steam reforming catalyst geometry has a direct effect on the efficiency and economy of hydrogen production from natural gas and is a very important technological and engineering issue in terms of process optimisation. This paper determines the influence of widely used seven-hole grain diameter (ranging from 11 to 21 mm), h/d (height/diameter) ratio of catalyst grain and Sh/St (hole surface/total cylinder surface in cross-section) ratio (ranging from 0.13 to 0.37) on the ...

  8. Kinetic behaviour of commercial catalysts for methane reforming in ethanol steam reforming process

    Institute of Scientific and Technical Information of China (English)

    Jorge Vicente; Javier Ere˜na; Martin Olazar; Pedro L. Benito; Javier Bilbao; Ana G. Gayubo

    2014-01-01

    Ethanol steam reforming has been studied in a fluidized bed (in order to ensure bed isothermicity) on commercial catalysts for methane reforming. The results allow analyzing the effect of temperature (in 300-700◦C range), and both metal and support nature on the reaction indices (ethanol conversion, yields and selectivities to H2 and byproducts (CO2, CO, CH4 and C2H4O)). Special attention has been paid to catalysts’ stability by comparing the evolution of the reaction indices with time on stream at 500◦C (minimum CO formation) and 700◦C (minimum deactivation by coke deposition). Although they provide a slightly lower H2 yield, the results evidence a good behaviour of Ni based catalysts, indicating that they are an interesting alternative of more expensive Rh based ones.

  9. Sorption-enhanced steam methane reforming in fluidized bed reactors

    Energy Technology Data Exchange (ETDEWEB)

    Johnsen, Kim

    2006-10-15

    Hydrogen is considered to be an important potential energy carrier; however, its advantages are unlikely to be realized unless efficient means can be found to produce it without generation of CO{sub 2}. Sorption-enhanced steam methane reforming (SE-SMR) represent a novel, energy-efficient hydrogen production route with in situ CO{sub 2} capture, shifting the reforming and water gas shift reactions beyond their conventional thermodynamic limits. The use of fluidized bed reactors for SE-SMR has been investigated. Arctic dolomite, a calcium-based natural sorbent, was chosen as the primary CO{sub 2}-acceptor in this study due to high absorption capacity, relatively high reaction rate and low cost. An experimental investigation was conducted in a bubbling fluidized bed reactor of diameter 0.1 m, which was operated cyclically and batch wise, alternating between reforming/carbonation conditions and higher-temperature calcination conditions. Hydrogen concentrations of >98 mole% on a dry basis were reached at 600 C and 1 atm, for superficial gas velocities in the range of {approx}0.03-0.1 m/s. Multiple reforming-regeneration cycles showed that the hydrogen concentration remained at {approx}98 mole% after four cycles. The total production time was reduced with an increasing number of cycles due to loss of CO{sub 2}-uptake capacity of the dolomite, but the reaction rates of steam reforming and carbonation seemed to be unaffected for the conditions investigated. A modified shrinking core model was applied for deriving carbonation kinetics of Arctic dolomite, using experimental data from a novel thermo gravimetric reactor. An apparent activation energy of 32.6 kj/mole was found from parameter fitting, which is in good agreement with previous reported results. The derived rate expression was able to predict experimental conversion up to {approx}30% very well, whereas the prediction of higher conversion levels was poorer. However, the residence time of sorbent in a continuous

  10. Investigations on a new internally-heated tubular packed-bed methanol–steam reformer

    KAUST Repository

    Nehe, Prashant

    2015-05-01

    Small-scale reformers for hydrogen production through steam reforming of methanol can provide an alternative solution to the demand of continuous supply of hydrogen gas for the operation of Proton Exchange Membrane Fuel Cells (PEMFCs). A packed-bed type reformer is one of the potential designs for such purpose. An externally heated reformer has issues of adverse lower temperature in the core of the reformer and significant heat loss to the environment thus impacting its performance. Experimental and numerical studies on a new concept of internally heated tubular packed-bed methanol-steam reformer have been reported in this paper with improved performance in terms of higher methanol conversion and reduced heat losses to surroundings. CuO/ZnO/Al2O3 is used as the catalyst for the methanol-steam reforming reaction and a rod-type electric heater at the center of the reactor is used for supplying necessary heat for endothermic steam reforming reaction. The vaporizer and the reformer unit with a constant volume catalyst bed are integrated in the annular section of a tubular reformer unit. The performance of the reformer was investigated at various operating conditions like feed rate of water-methanol mixture, mass of the catalyst and reforming temperature. The experimental and numerical results show that the methanol conversion and CO concentration increase with internal heating for a wide range of operating conditions. The developed reformer unit generates 50-80W (based on lower heating value) of hydrogen gas for applications in PEMFCs. For optimized design and operating conditions, the reformer unit produced 298sccm reformed gas containing 70% H2, 27% CO2 and 3% CO at 200-240°C which can produce a power output of 25-32W assuming 60% fuel cell efficiency and 80% of hydrogen utilization in a PEMFC. © 2015 Hydrogen Energy Publications, LLC.

  11. Lab and Bench-Scale Pelletization of Torrefied Wood Chips

    DEFF Research Database (Denmark)

    Shang, Lei; Nielsen, Niels Peter K.; Stelte, Wolfgang;

    2013-01-01

    Combined torrefaction and pelletization is used to increase the fuel value of biomass by increasing its energy density and improving its handling and combustion properties. In the present study, a single-pellet press tool was used to screen for the effects of pellet die temperature, moisture...... content, additive addition, and the degree of torrefaction on the pelletizing properties and pellet quality, i.e., density, static friction, and pellet strength. Results were compared with pellet production using a bench-scale pelletizer. The results indicate that friction is the key factor when scaling...... up from single-pellet press to bench-scale pelletizer. Tuning moisture content or increasing the die temperature did not ease the pellet production of torrefied wood chips significantly. The addition of rapeseed oil as a lubricant reduced the static friction by half and stabilized pellet production...

  12. Rare-earth oxides promoted nickel based catalysts for steam reforming

    International Nuclear Information System (INIS)

    Full text: The effect of ceria, samaria and praseodymia as promoters for nickel based catalysts for the steam reforming of methane has been studied. The catalysts, prepared by a two-step impregnation method, showed significant enhancement of activity for methane steam reforming. The activity increased linearly with increased loading of the rare-earth oxides. The positive effect of the rare-earth oxides on the steam reforming activity decreased as CeO2>Pr2O3>Sm2O3. The ceria-containing catalysts exhibited excellent anti-coking ability comparable to that of advanced commercial catalysts. This was explained in terms of the larger adsorption of water on the surface of ceria and the resulting relatively high rates of carbon gasification. The selectivity of the nickel-ceria catalysts to hydrogen and carbon dioxide production during methane steam re-forming was also significantly improved due to the increase of importance of the water gas shift reaction

  13. Kinetic model on coke oven gas with steam reforming

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jia-yuan; ZHOU Jie-min; YAN Hong-jie

    2008-01-01

    The effects of factors such as the molar ratio of H2O to CH4 (n(H2O)/n(CH4)), methane conversion temperature and time on methane conversion rate were investigated to build kinetic model for reforming of coke-oven gas with steam. The results of experiments show that the optimal conditions for methane conversion are that the molar ratio of H2O to CH4 varies from 1.1 to 1.3and the conversion temperature varies from 1 223 to 1 273 K. The methane conversion rate is more than 95% when the molar ratio ofH2O to CH4 is 1.2, the conversion temperature is above 1 223 K and the conversion time is longer than 0.75 s. Kinetic model of methane conversion was proposed. All results demonstrate that the calculated values by the kinetic model accord with the experimental data well, and the error is less than 1.5%.

  14. FLUIDIZED BED STEAM REFORMING ENABLING ORGANIC HIGH LEVEL WASTE DISPOSAL

    International Nuclear Information System (INIS)

    Waste streams planned for generation by the Global Nuclear Energy Partnership (GNEP) and existing radioactive High Level Waste (HLW) streams containing organic compounds such as the Tank 48H waste stream at Savannah River Site have completed simulant and radioactive testing, respectfully, by Savannah River National Laboratory (SRNL). GNEP waste streams will include up to 53 wt% organic compounds and nitrates up to 56 wt%. Decomposition of high nitrate streams requires reducing conditions, e.g. provided by organic additives such as sugar or coal, to reduce NOX in the off-gas to N2 to meet Clean Air Act (CAA) standards during processing. Thus, organics will be present during the waste form stabilization process regardless of the GNEP processes utilized and exists in some of the high level radioactive waste tanks at Savannah River Site and Hanford Tank Farms, e.g. organics in the feed or organics used for nitrate destruction. Waste streams containing high organic concentrations cannot be stabilized with the existing HLW Best Developed Available Technology (BDAT) which is HLW vitrification (HLVIT) unless the organics are removed by pretreatment. The alternative waste stabilization pretreatment process of Fluidized Bed Steam Reforming (FBSR) operates at moderate temperatures (650-750 C) compared to vitrification (1150-1300 C). The FBSR process has been demonstrated on GNEP simulated waste and radioactive waste containing high organics from Tank 48H to convert organics to CAA compliant gases, create no secondary liquid waste streams and create a stable mineral waste form

  15. FLUIDIZED BED STEAM REFORMING ENABLING ORGANIC HIGH LEVEL WASTE DISPOSAL

    Energy Technology Data Exchange (ETDEWEB)

    Williams, M

    2008-05-09

    Waste streams planned for generation by the Global Nuclear Energy Partnership (GNEP) and existing radioactive High Level Waste (HLW) streams containing organic compounds such as the Tank 48H waste stream at Savannah River Site have completed simulant and radioactive testing, respectfully, by Savannah River National Laboratory (SRNL). GNEP waste streams will include up to 53 wt% organic compounds and nitrates up to 56 wt%. Decomposition of high nitrate streams requires reducing conditions, e.g. provided by organic additives such as sugar or coal, to reduce NOX in the off-gas to N2 to meet Clean Air Act (CAA) standards during processing. Thus, organics will be present during the waste form stabilization process regardless of the GNEP processes utilized and exists in some of the high level radioactive waste tanks at Savannah River Site and Hanford Tank Farms, e.g. organics in the feed or organics used for nitrate destruction. Waste streams containing high organic concentrations cannot be stabilized with the existing HLW Best Developed Available Technology (BDAT) which is HLW vitrification (HLVIT) unless the organics are removed by pretreatment. The alternative waste stabilization pretreatment process of Fluidized Bed Steam Reforming (FBSR) operates at moderate temperatures (650-750 C) compared to vitrification (1150-1300 C). The FBSR process has been demonstrated on GNEP simulated waste and radioactive waste containing high organics from Tank 48H to convert organics to CAA compliant gases, create no secondary liquid waste streams and create a stable mineral waste form.

  16. Large scale experiment tests of the heat linkage between HTR and steam/methane reforming process

    International Nuclear Information System (INIS)

    The EVA Pilot Plant of the KFA Julich has been operating since the beginning of 1973. The heat linkage between HTR and steam/methane reforming process is investigated at an industrial reforming tube. Technical data and constructional details of the plant and a survey of the present results are given. (author)

  17. Dynamic simulation of a furnace of steam reforming of natural gas

    International Nuclear Information System (INIS)

    Steam reforming of natural gas is a very important industrial process in refineries and ammonia and methanol plants. Hydrogen is produced by reforming methane with steam. This hydrogen is essential in the hydro-treating process in the refineries thus, it is important to supervise and control the performance of the hydrogen plant. Mathematical models of refineries and chemical plants are used to simulate the behavior of the process units. However, the models especially of reactors like reformers are not very reliable. This paper presents a dynamic model of a furnace-reactor. The simulation results are validated with industrial data

  18. High-temperature gas-cooled-reactor steam-methane reformer design

    International Nuclear Information System (INIS)

    The concept of the long distance transportation of process heat energy from a High Temperature Gas Cooled Reactor (HTGR) heat source, based on the steam reforming reaction, is currently being evaluated as an energy source/application for use early in the 21st century. The steam-methane reforming reaction is an endothermic reaction at temperatures approximately 7000C and higher, which produces hydrogen, carbon monoxide and carbon dioxide. The heat of the reaction products can then be released, after being pumped to industrial site users, in a methanation process producing superheated steam and methane which is then returned to the reactor plant site. In this application the steam reforming reaction temperatures are produced by the heat energy from the core of the HTGR through forced convection of the primary or secondary helium circuit to the catalytic chemical reactor (steam reformer). This paper summarizes the design of a helium heated steam reformer utilized in conjunction with a 1170 MW(t) intermediate loop, 8500C reactor outlet temperature, HTGR process heat plant concept. This paper also discusses various design considerations leading to the mechanical design features, the thermochemical performance, materials selection and the structural design analysis

  19. Modeling, Simulation and Optimization of Hydrogen Production Process from Glycerol using Steam Reforming

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jeongpil; Cho, Sunghyun; Kim, Tae-Ok; Shin, Dongil [Myongji University, Yongin (Korea, Republic of); Lee, Seunghwan [JNK Heaters, Seoul (Korea, Republic of); Moon, Dong Ju [Korea Institute of Science and Technology, Seoul (Korea, Republic of)

    2014-12-15

    For improved sustainability of the biorefinery industry, biorefinery-byproduct glycerol is being investigated as an alternate source for hydrogen production. This research designs and optimizes a hydrogen-production process for small hydrogen stations using steam reforming of purified glycerol as the main reaction, replacing existing processes relying on steam methane reforming. Modeling, simulation and optimization using a commercial process simulator are performed for the proposed hydrogen production process from glycerol. The mixture of glycerol and steam are used for making syngas in the reforming process. Then hydrogen are produced from carbon monoxide and steam through the water-gas shift reaction. Finally, hydrogen is separated from carbon dioxide using PSA. This study shows higher yield than former U.S.. DOE and Linde studies. Economic evaluations are performed for optimal planning of constructing domestic hydrogen energy infrastructure based on the proposed glycerol-based hydrogen station.

  20. Steam reforming as a method to treat Hanford underground storage tank (UST) wastes

    International Nuclear Information System (INIS)

    This report summarizes a Sandia program that included partnerships with Lawrence Livermore National Laboratory and Synthetica Technologies, Inc. to design and test a steam reforming system for treating Hanford underground storage tank (UST) wastes. The benefits of steam reforming the wastes include the resolution of tank safety issues and improved radionuclide separations. Steam reforming destroys organic materials by first gasifying, then reacting them with high temperature steam. Tests indicate that up to 99% of the organics could be removed from the UST wastes by steam exposure. In addition, it was shown that nitrates in the wastes could be destroyed by steam exposure if they were first distributed as a thin layer on a surface. High purity alumina and nickel alloys were shown to be good candidates for materials to be used in the severe environment associated with steam reforming the highly alkaline, high nitrate content wastes. Work was performed on designing, building, and demonstrating components of a 0.5 gallon per minute (gpm) system suitable for radioactive waste treatment. Scale-up of the unit to 20 gpm was also considered and is feasible. Finally, process demonstrations conducted on non-radioactive waste surrogates were carried out, including a successful demonstration of the technology at the 0.1 gpm scale

  1. Operation of an industrial steam reformer under severe condition : a simulation study

    Energy Technology Data Exchange (ETDEWEB)

    Shayegan, J. [Sharif Univ., Tehran (Iran, Islamic Republic of). Dept of Chemical and Petroleum Engineering; Yousef Motamed Hashemi, M.M. [Southern California Univ., Los Angeles, CA (United States). Mork Family Dept. of Chemical Engineering and Material Sciences; Vakhshouri, K. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Chemical and Biological Engineering

    2008-08-15

    Steam reforming involves the reaction of hydrocarbons with water vapours in order to produce hydrogen and carbon monoxide (CO). Reformers typically use nickel catalysts to accelerate reforming reactions. Large quantities of heat are needed to react the hydrocarbons. This article described a 2-D model designed to simulate steam reformers with lower generating Reynolds numbers, a higher tube diameter, and the non-availability of extra steam in the feed. Reformer feed gas was a mixture of fresh natural gas and off-gas streams. Carbon dioxide (CO{sub 2}) content was higher than conventional steam reformers. The steady state operation of a large-scale Midrex reformer was investigated in order to obtain furnace-side and reactor-side equations. A Roesler flux-type model was used to model the furnace-side. The reactor side model used a fluid radial Peclet number as well as an extension of Ergun's equation in order to estimate pressure drop. Reactions were evaluated by a set of first order kinetic expressions. Thermodynamic properties of combustion products and process gases were obtained using SRK equations of state. Axial and radial temperature profiles were obtained, and the effect of the catalyst loading profile was investigated. The study showed that the 2-D model was adequate but not entirely accurate. It was concluded that further research is needed to understand the effects of catalyst loading profiles and the risks of carbon formation. 30 refs., 7 tabs., 6 figs.

  2. FLUIDIZED BED STEAM REFORMER (FBSR) PRODUCT: MONOLITH FORMATION AND CHARACTERIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C

    2006-09-13

    The most important requirement for Hanford's low activity waste (LAW) form for shallow land disposal is the chemical durability of the product. A secondary, but still essential specification, is the compressive strength of the material with regards to the strength of the material under shallow land disposal conditions, e.g. the weight of soil overburden and potential intrusion by future generations, because the term ''near-surface disposal'' indicates disposal in the uppermost portion, or approximately the top 30 meters, of the earth's surface. The THOR{reg_sign} Treatment Technologies (TTT) mineral waste form for LAW is granular in nature because it is formed by Fluidized Bed Steam Reforming (FBSR). As a granular product it has been shown to be as durable as Hanford's LAW glass during testing with ASTM C-1285-02 known as the Product Consistency Test (PCT) and with the Single Pass Flow Through Test (SPFT). Hanford Envelope A and Envelope C simulants both performed well during PCT and SPFT testing and during subsequent performance assessment modeling. This is partially due to the high aluminosilicate content of the mineral product which provides a natural aluminosilicate buffering mechanism that inhibits leaching and is known to occur in naturally occurring aluminosilicate mineral analogs. In order for the TTT Na-Al-Si (NAS) granular mineral product to meet the compressive strength requirements (ASTM C39) for a Hanford waste form, the granular product needs to be made into a monolith or disposed of in High Integrity Containers (HIC's). Additionally, the Hanford intruder scenario for disposal in the Immobilized Low Activity Waste (ILAW) trench is mitigated as there is reduced intruder exposure when a waste form is in a monolithic form. During the preliminary testing of a monolith binder for TTT's FBSR mineral product, four parameters were monitored: (1) waste loading (not optimized for each waste form tested); (2) density

  3. Production of synthetic fuels using syngas from a steam hydrogasification and reforming process

    Science.gov (United States)

    Raju, Arun Satheesh Kumar

    This thesis is aimed at the research, optimization and development of a thermo-chemical process aimed at the production of synthesis gas (mixture of H2 and CO) with a flexible H2 to CO ratio using coupled steam hydrogasification and steam reforming processes. The steam hydrogasification step generates a product gas containing significant amounts of methane by gasifying a carbonaceous feed material with steam and internally generated H2. This product gas is converted to synthesis gas with an excess H2 to CO using the steam reformer. Research involving experimental and simulation work has been conducted on steam hydrogasification, steam reforming and the Fischer-Tropsch reaction. The Aspen Plus simulation tool has been used to develop a process model that can perform heat and mass balance calculations of the whole process using built-in reactor modules and an empirical FT model available in the literature. This model has been used to estimate optimum feed ratios and process conditions for specific feedstocks and products. Steam hydrogasification of coal and wood mixtures of varying coal to wood ratios has been performed in a stirred batch reactor. The carbon conversion of the feedstocks to gaseous products is around 60% at 700°C and 80% at 800°C. The coal to wood ratio of the feedstock does not exert a significant influence on the carbon conversion. The rates of formation of CO, CO 2 and CH4 during gasification have been calculated based on the experimental results using a simple kinetic model. Experimental research on steam reforming has been performed. It has been shown that temperature and the feed CO2/CH4 ratio play a dominant role in determining the product gas H2/CO ratio. Reforming of typical steam hydrogasification product-gas stream has been investigated over a commercial steam reforming catalyst. The results demonstrate that the combined use of steam hydrogasification process with a reformer can generate a synthesis gas with a predetermined H2/CO ratio

  4. DURABILITY TESTING OF FLUIDIZED BED STEAM REFORMER (FBSR) WASTE FORMS

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C

    2006-01-06

    Fluidized Bed Steam Reforming (FBSR) is being considered as a potential technology for the immobilization of a wide variety of high sodium aqueous radioactive wastes. The addition of clay and a catalyst as co-reactants converts high sodium aqueous low activity wastes (LAW) such as those existing at the Hanford and Idaho DOE sites to a granular ''mineralized'' waste form that may be made into a monolith form if necessary. Simulant Hanford and Idaho high sodium wastes were processed in a pilot scale FBSR at Science Applications International Corporation (SAIC) Science and Technology Applications Research (STAR) facility in Idaho Falls, ID. Granular mineral waste forms were made from (1) a basic Hanford Envelope A low-activity waste (LAW) simulant and (2) an acidic INL simulant commonly referred to as sodium-bearing waste (SBW). The FBSR waste forms were characterized and the durability tested via ASTM C1285 (Product Consistency Test), the Environmental Protection Agency (EPA) Toxic Characteristic Leaching Procedure (TCLP), and the Single Pass Flow Through (SPFT) test. The durability of the FBSR waste form products was tested in order to compare the measured durability to previous FBSR waste form testing on Hanford Envelope C waste forms that were made by THOR Treatment Technologies (TTT) and to compare the FBSR durability to vitreous LAW waste forms, specifically the Hanford low activity waste (LAW) glass known as the Low-activity Reference Material (LRM). The durability of the FBSR waste form is comparable to that of the LRM glass for the test responses studied.

  5. Experiments for combining nuclear heat with the methane steam-reforming process

    International Nuclear Information System (INIS)

    A high temperature reactor with the cooling gas helium leaving at an average temperature of 9500C offers an interesting possibility for combining nuclear heat with the methane steam-reforming process. However, the incorporation of nuclear heat into this process still requires comprehensive experimental and theoretical studies before an economic and technical optimization of a combined nuclear/chemical plant can be reached. Thus the EVA (single reforming tube, Einzelrohr-Versuchsanlage) pilot plant was set up to examine the methane steam-reforming process in a helium-heated conventional reforming tube. This report describes the plant and specifies some representative experimental results. It follows that convective helium heating is an appropriate method of transferring heat to the reforming tube. In addition, the report describes two accompanying experiments in smaller high pressure test plants and summarizes some of the measured results. (Auth.)

  6. Bench-scale magnetic separation of Department of Energy wastes

    International Nuclear Information System (INIS)

    Criteria were developed for selection of candidate wastes for testing magnetic separation of uranium and/or other paramagnetic materials. A survey of Department of Energy (DOE) hazardous wastes was conducted to determine good candidates for bench-scale magnetic separation tests. Representatives of 21 DOE sites were contacted, and 11 materials were identified as potential candidates for magnetic separation. To date, seven samples have been obtained and tested for separability of uranium with a bench-scale magnetic assaying device. The samples tested have been obtained from the K-1401B and K-1401C ponds in Oak Ridge, Tennessee; from waste piles in Maywood, New Jersey; from North and South Ponds in Richland, Washington; and from magnesium fluoride drums in Fernald, Ohio. The magnetic device utilized in these tests can be used in an open-gradient mode with dry particulate or liquid-suspended materials. Uranium separation from magnesium fluoride has shown exceptionally good performance in both open- and high-gradient modes and could be an important application of the technology

  7. Bench-scale Analysis of Surrogates for Anaerobic Digestion Processes.

    Science.gov (United States)

    Carroll, Zachary S; Long, Sharon C

    2016-05-01

    Frequent monitoring of anaerobic digestion processes for pathogen destruction is both cost and time prohibitive. The use of surrogates to supplement regulatory monitoring may be one solution. To evaluate surrogates, a semi-batch bench-scale anaerobic digester design was tested. Bench-scale reactors were operated under mesophilic (36 °C) and thermophilic (53-55 °C) conditions, with a 15 day solids retention time. Biosolids from different facilities and during different seasons were examined. USEPA regulated pathogens and surrogate organisms were enumerated at different times throughout each experiment. The surrogate organisms included fecal coliforms, E. coli, enterococci, male-specific and somatic coliphages, Clostridium perfringens, and bacterial spores. Male-specific coliphages tested well as a potential surrogate organism for virus inactivation. None of the tested surrogate organisms correlated well with helminth inactivation under the conditions studied. There were statistically significant differences in the inactivation rates between the facilities in this study, but not between seasons. PMID:27131309

  8. New Insights into Reaction Mechanisms of Ethanol Steam Reforming on Co-ZrO2

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Junming; Karim, Ayman M.; Mei, Donghai; Engelhard, Mark H.; Bao, Xinhe; Wang, Yong

    2015-01-01

    The reaction pathway of ethanol steam reforming on Co-ZrO2 has been identified and the active sites associated with each step are proposed. Ethanol is converted to acetaldehyde and then to acetone, followed by acetone steam reforming. More than 90% carbon was found to follow this reaction pathway. N2-Sorption, X-ray Diffraction (XRD), Temperature Programmed Reduction (TPR), in situ X-ray Photoelectron Spectroscopy (XPS), Transmission Electron Microscopy, as well as theoretical Density Functional Theory (DFT) calculations have been employed to identify the structure and functionality of the catalysts, which was further used to correlate their performance in ESR. It was found that metallic cobalt is mainly responsible for the acetone steam reforming reactions; while, CoO and basic sites on the support play a key role in converting ethanol to acetone via dehydrogenation and condensation/ketonization reaction pathways. The current work provides fundamental understanding of the ethanol steam reforming reaction mechanisms on Co-ZrO2 catalysts and sheds light on the rational design of selective and durable ethanol steam reforming catalysts.

  9. In-Space Propulsion, Logistics Reduction, and Evaluation of Steam Reformer Kinetics: Problems and Prospects

    Science.gov (United States)

    Jaworske, D. A.; Palaszewski, B. A.; Kulis, M. J.; Gokoglu, S. A.

    2015-01-01

    Human space missions generate waste materials. A 70-kg crewmember creates a waste stream of 1 kg per day, and a four-person crew on a deep space habitat for a 400+ day mission would create over 1600 kg of waste. Converted into methane, the carbon could be used as a fuel for propulsion or power. The NASA Advanced Exploration Systems (AES) Logistics Reduction and Repurposing (LRR) project is investing in space resource utilization with an emphasis on repurposing logistics materials for useful purposes and has selected steam reforming among many different competitive processes as the preferred method for repurposing organic waste into methane. Already demonstrated at the relevant processing rate of 5.4 kg of waste per day, high temperature oxygenated steam consumes waste and produces carbon dioxide, carbon monoxide, and hydrogen which can then be converted into methane catalytically. However, the steam reforming process has not been studied in microgravity. Data are critically needed to understand the mechanisms that allow use of steam reforming in a reduced gravity environment. This paper reviews the relevant literature, identifies gravity-dependent mechanisms within the steam gasification process, and describes an innovative experiment to acquire the crucial kinetic information in a small-scale reactor specifically designed to operate within the requirements of a reduced gravity aircraft flight. The experiment will determine if the steam reformer process is mass-transport limited, and if so, what level of forced convection will be needed to obtain performance comparable to that in 1-g.

  10. Hydrogen production from biomass pyrolysis gas via high temperature steam reforming process

    International Nuclear Information System (INIS)

    Full text: The aim of this work has been undertaken as part of the design of continuous hydrogen production using the high temperature steam reforming process. The steady-state test condition was carried out using syngas from biomass pyrolysis, whilst operating at high temperatures between 600 and 1200 degree Celsius. The main reformer operating parameters (e.g. temperature, resident time and steam to biomass ratio (S/B)) have been examined in order to optimize the performance of the reformer. The operating temperature is a key factor in determining the extent to which hydrogen production is increased at higher temperatures (900 -1200 degree Celsius) whilst maintaining the same as resident time and S/B ratio. The effects of exhaust gas composition on heating value were also investigated. The steam reforming process produced methane (CH4) and ethylene (C2H4) between 600 to 800 degree Celsius and enhanced production ethane (C2H6) at 700 degree Celsius. However carbon monoxide (CO) emission was slightly increased for higher temperatures all conditions. The results show that the use of biomass pyrolysis gas can produce higher hydrogen production from high temperature steam reforming. In addition the increasing reformer efficiency needs to be optimized for different operating conditions. (author)

  11. Steam reforming on transition-metal carbides from density-functional theory

    CERN Document Server

    Vojvodic, Aleksandra

    2009-01-01

    A screening study of the steam reforming reaction (CH_4 + H_2O -> CO + 3H_2) on early transition-metal carbides (TMC's) is performed by means of density-functional theory calculations. The set of considered surfaces includes the alpha-Mo_2C(100) surfaces, the low-index (111) and (100) surfaces of TiC, VC, and delta-MoC, and the oxygenated alpha-Mo_2C(100) and TMC(111) surfaces. It is found that carbides provide a wide spectrum of reactivities towards the steam reforming reaction, from too reactive via suitable to too inert. The reactivity is discussed in terms of the electronic structure of the clean surfaces. Two surfaces, the delta-MoC(100) and the oxygen passivated alpha-Mo_2C(100) surfaces, are identified as promising steam reforming catalysts. These findings suggest that carbides provide a playground for reactivity tuning, comparable to the one for pure metals.

  12. First principles calculations and experimental insight into methane steam reforming over transition metal catalysts

    DEFF Research Database (Denmark)

    Jones, Glenn; Jakobsen, Jon Geest; Shim, Signe Sarah;

    2008-01-01

    situ TEM measurements under a hydrogen atmosphere. The overall agreement between theory and experiment (at 773 K, 1 bar pressure and 10% conversion) is found to be excellent with Ru and Rh being the most active pure transition metals for methane steam reforming, while Ni, Ir, Pt, and Pd are...... metal Surfaces to develop an overview of the steam reforming process catalyzed by a range of transition metal surfaces. By combining scaling relationships with thermodynamic and kinetic analysis, we show that it is possible to determine the reactivity trends of the pure metals for methane steam...... reforming. The reaction is found to be kinetically controlled by a methane dissociation step and a CO formation step, where the latter step is found to be dominant at lower temperatures. The particle size of the metal catalysts particles have been determined by transmission electron microscopy (TEM) and the...

  13. Steam Reforming Technology for Denitration and Immobilization of DOE Tank Wastes

    International Nuclear Information System (INIS)

    THOR Treatment Technologies, LLC (THOR) is a joint venture formed in June 2002 by Studsvik, Inc. (Studsvik) and Westinghouse Government Environmental Services Company LLC to further develop, market, and deploy Studsvik's patented THORSM non-incineration, steam reforming waste treatment technology. This paper provides an overview of the THORSM steam reforming process as applied to the denitration and conversion of Department of Energy (DOE) tank wastes to an immobilized mineral form. Using the THORSM steam reforming technology to treat nitrate containing tank wastes could significantly benefit the DOE by reducing capital and life-cycle costs, reducing processing and programmatic risks, and positioning the DOE to meet or exceed its stakeholder commitments for tank closure. Specifically, use of the THORSM technology can facilitate processing of up to 75% of tank wastes without the use of vitrification, yielding substantial life-cycle cost savings

  14. Development of Ni-Based Catalysts for Steam Reforming of Tar Derived from Biomass Pyrolysis

    Institute of Scientific and Technical Information of China (English)

    Dalin LI; Yoshinao NAKAGAWA; Keiichi TOMISHIGE

    2012-01-01

    Nickel catalysts are effective for the steam reforming of tar derived from biomass pyrolysis,but the improvement is needed in terms of activity,stability,suppression of coke deposition and aggregation,and regeneration.Our recent development of Ni-based catalysts for the steam reforming of tar is reviewed including the modification with CeO2 (or MnO),trace Pt,and MgO.The role of additives such as CeO2,MnO,Pt,and MgO is also discussed.

  15. Computational fluid dynamics simulation of ethanol steam reforming in catalytic wall microchannels

    OpenAIRE

    Uriz, I.; Arzamendi, G.; López, E.; Llorca Piqué, Jordi; Gandía, L.M.

    2011-01-01

    A three-dimensional computational fluid dynamics (CFD) simulation study of the ethanol steam reforming (ESR) in microreactors with square channels has been carried out. A phenomenological kinetic model describing the ESR on a Co3O4–ZnO catalyst has been established and implemented in the CFD codes. This model includes the ethanol dehydrogenation to acetaldehyde, ethanol decomposition to CO and CH4, acetaldehyde steam reforming to H2 and CO2 and water–gas shift as the reactions des...

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

    DEFF Research Database (Denmark)

    Mogensen, David

    Solid Oxide Fuel Cells (SOFC) is a technology with great potential. Its high efficiency makes it a relevant alternative to existing technologies for utilizing fossil fuels and its fuel versatility makes it invaluable in the transition from a fossil fuel based energy system to on based on renewable...... energy. The overall efficiency of a fuel cell system operating on natural gas can be significantly improved by having part of the steam reforming take place inside the SOFC stack. In order to avoid large temperature gradients as a result of the highly endothermal steam reforming reaction, the amount of...

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

    DEFF Research Database (Denmark)

    Mogensen, David

    Solid Oxide Fuel Cells (SOFC) is a technology with great potential. Its high efficiency makes it a relevant alternative to existing technologies for utilizing fossil fuels and its fuel versatility makes it invaluable in the transition from a fossil fuel based energy system to on based on renewable...... energy. The overall efficiency of a fuel cell system operating on natural gas can be significantly improved by having part of the steam reforming take place inside the SOFC stack. In order to avoid large temperature gradients as a result of the highly endothermal steam reforming reaction, the amount of...

  18. Bench-Scale Demonstration of Hot-Gas Desulfurization Technology

    International Nuclear Information System (INIS)

    Prior to the current project, development of the DSRP was done in a laboratory setting, using synthetic gas mixtures to simulate the regeneration off-gas and coal gas feeds. The objective of the current work is to further the development of zinc titanate fluidized-bed desulfurization (ZTFBD) and the DSRP for hot-gas cleanup by testing with actual coal gas. The objectives of this project are to: (1) Develop and test an integrated, skid-mounted, bench-scale ZTFBD/DSRP reactor system with a slipstream of actual coal gas; (2) Test the bench-scale DSRP over an extended period with a slipstream of actual coal gas to quantify the degradation in performance, if any, caused by the trace contaminants present in coal gas (including heavy metals, chlorides, fluorides, and ammonia); (3) Expose the DSRP catalyst to actual coal gas for extended periods and then test its activity in a laboratory reactor to quantify the degradation in performance, if any, caused by static exposure to the trace contaminants in coal gas; (4) Design and fabricate a six-fold larger-scale DSRP reactor system for future slipstream testing; (5) Further develop the fluidized-bed DSRP to handle high concentrations (up to 14 percent) of SO2 that are likely to be encountered when pure air is used for regeneration of desulfurization sorbents; and (6) Conduct extended field testing of the 6X DSRP reactor with actual coal gas and high concentrations of SO2. The accomplishment of the first three objectives--testing the DSRP with actual coal gas, integration with hot-gas desulfurization, and catalyst exposure testing--was described previously (Portzer and Gangwal, 1994, 1995; Portzer et al., 1996). This paper summarizes the results of previous work and describes the current activities and plans to accomplish the remaining objectives

  19. Numerical study of heat mass transfer characteristics in microchannel steam methane reforming reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Seung Won; Lee, Kyn Jung; Cho, Yeon Hwa [Korea Univ., Seoul (Korea, Republic of); Moon, Dong Ju [Korea Institute of Science and Technology, Seoul (Korea, Republic of)

    2012-09-15

    A numerical study of a microchannel steam methane reforming reactor has been performed to understand the characteristics of heat and mass transfer. The integration of Rh catalyzed steam methane reforming and Pt catalyzed methane combustion has been simulated. The reaction rates for chemical reactions have been incorporated into the simulation. This study investigated the effect of contact time, flow pattern (parallel of counter), and channel size on the reforming performance and temperature distribution. The parallel and counter flow have opposite temperature distribution, and they show a different type of reaction rate and species mole fraction. As the contact time decreases and channel size increases, mass transfer between the catalyst layer and the flow is limited, and the reforming performance is decreased.

  20. Numerical study of heat mass transfer characteristics in microchannel steam methane reforming reactor

    International Nuclear Information System (INIS)

    A numerical study of a microchannel steam methane reforming reactor has been performed to understand the characteristics of heat and mass transfer. The integration of Rh catalyzed steam methane reforming and Pt catalyzed methane combustion has been simulated. The reaction rates for chemical reactions have been incorporated into the simulation. This study investigated the effect of contact time, flow pattern (parallel of counter), and channel size on the reforming performance and temperature distribution. The parallel and counter flow have opposite temperature distribution, and they show a different type of reaction rate and species mole fraction. As the contact time decreases and channel size increases, mass transfer between the catalyst layer and the flow is limited, and the reforming performance is decreased

  1. Preparation of Hydrogen through Catalytic Steam Reforming of Bio-oil

    Institute of Scientific and Technical Information of China (English)

    吴层; 颜涌捷; 李庭琛; 亓伟

    2007-01-01

    Hydrogen was prepared via catalytic steam reforming of bio-oil which was obtained from fast pyrolysis of biomass in a fluidized bed reactor. Influential factors including temperature, weight hourly space velocity (WHSV) of bio-oil, mass ratio of steam to bio-oil (S/B) as well as catalyst type on hydrogen selectivity and other desirable gas products were investigated. Based on hydrogen in stoichiometric potential and carbon balance in gaseous phase and feed, hydrogen yield and carbon selectivity were examined. The experimental results show that higher temperature favors the hydrogen selectivity by H2 mole fraction in gaseous products stream and it plays an important role in hydrogen yield and carbon selectivity. Higher hydrogen selectivity and yield, and carbon selectivity were obtained at lower bio-oil WHSV. In catalytic steam reforming system a maximum steam concentration value exists, at which hydrogen selectivity and yield, and carbon selectivity keep constant. Through experiments, preferential operation conditions were obtained as follows: temperature 800~850℃, bio-oil WHSV below 3.0 h-1, and mass ratio of steam to bio-oil 10~12. The performance tests indicate that Ni-based catalysts are optional, especially Ni/a-Al2O3 effective in the steam reforming process.

  2. Steam reforming of fuel to hydrogen in fuel cells

    International Nuclear Information System (INIS)

    A fuel cell is claimed capable of utilizing a hydrocarbon such as methane as fuel and having an internal dual catalyst system within the anode zone, the dual catalyst system including an anode catalyst supporting and in heat conducting relationship with a reforming catalyst with heat for the reforming reaction being supplied by the reaction at the anode catalyst

  3. PRODUCTION OF HYDROGEN FROM THE STEAM AND OXIDATIVE REFORMING OF LPG: THERMODYNAMIC AND EXPERIMENTAL STUDY

    OpenAIRE

    P. P. Silva; Ferreira, R A; J.F. Nunes; Sousa, J.A.; L. L. Romanielo; F. B. Noronha; HORI C. E.

    2015-01-01

    AbstractThe objective of this paper was to use a thermodynamic analysis to find operational conditions that favor the production of hydrogen from steam and oxidative reforming of liquefied petroleum gas (LPG). We also analyzed the performance of a catalyst precursor, LaNiO3, in order to compare the performance of the obtained catalyst with the thermodynamic equilibrium predictions. The results showed that it is possible to produce high concentrations of hydrogen from LPG reforming. The gradua...

  4. A methanol steam reforming micro reactor for proton exchange membrane micro fuel cell system

    International Nuclear Information System (INIS)

    The heat, mass and momentum transfer from a fuel reforming packed bed to a surrounding silicon wafer has been simulated. Modeling showed quantitatively reasonable agreement with experimental data for fuel conversion efficiency, hydrogen production rate, outlet methanol mole fraction and outlet steam mole fraction. The variation in fuel conversion efficiency with the micro reformer thermal isolation can be used to optimize fuel-processing conditions for micro PEM fuel cells. (author)

  5. Design of linear controllers applied to an ethanol steam reformer for PEM fuel cell applications

    OpenAIRE

    García, Vanesa M.; Serra, Maria; Llorca, Jordi; Riera, Jordi

    2013-01-01

    This paper focuses on the design of a controller for a low temperature ethanol steam reformer for the production of hydrogen to feed a protonic exchange membrane (PEM) fuel cell. It describes different control structures for the reformer and treats the control structure selection of this multiple input multiple output (MIMO) system. For each considered control structure, decentralised 2 × 2 controllers with proportional integral (PI) control actions in each control loop are implemented. The t...

  6. Thermodynamic modeling of the power plant based on the SOFC with internal steam reforming of methane

    International Nuclear Information System (INIS)

    Mathematical model based on the thermodynamic modeling of gaseous mixtures is developed for SOFC with internal steam reforming of methane. Macroscopic porous-electrode theory, including non-linear kinetics and gas-phase diffusion, is used to calculate the reforming reaction and the concentration polarization. Provided the data concerning properties and costs of materials the model is fit for wide range of parametric analysis of thermodynamic cycles including SOFC

  7. 2D heat and mass transfer modeling of methane steam reforming for hydrogen production in a compact reformer

    International Nuclear Information System (INIS)

    Highlights: ► A heat and mass transfer model is developed for a compact reformer. ► Hydrogen production from methane steam reforming is simulated. ► Increasing temperature greatly increases the reaction rates at the inlet. ► Temperature in the downstream is increased at higher rate of heat supply. ► Larger permeability enhances gas flow and reaction rates in the catalyst layer. - Abstract: Compact reformers (CRs) are promising devices for efficient fuel processing. In CRs, a thin solid plate is sandwiched between two catalyst layers to enable efficient heat transfer from combustion duct to the reforming duct for fuel processing. In this study, a 2D heat and mass transfer model is developed to investigate the fundamental transport phenomenon and chemical reaction kinetics in a CR for hydrogen production by methane steam reforming (MSR). Both MSR reaction and water gas shift reaction (WGSR) are considered in the numerical model. Parametric simulations are performed to examine the effects of various structural/operating parameters, such as pore size, permeability, gas velocity, temperature, and rate of heat supply on the reformer performance. It is found that the reaction rates of MSR and WGSR are the highest at the inlet but decrease significantly along the reformer. Increasing the operating temperature raises the reaction rates at the inlet but shows very small influence in the downstream. For comparison, increasing the rate of heat supply raises the reaction rates in the downstream due to increased temperature. A high gas velocity and permeability facilitates gas transport in the porous structure thus enhances reaction rates in the downstream of the reformer.

  8. Numerical study of effect of operating and design parameters for design of steam reforming reactor

    International Nuclear Information System (INIS)

    A numerical study on the design of a steam reforming reactor consisting of several reforming tubes and one burner is conducted with respect to various operating and design parameters such as GHSV (gas hourly space velocity), input heat capacity, catalyst layer length, and number of tubes. The calculation of the reforming reaction rate is coupled with a three-dimensional heat and mass transfer calculation. It is shown that a large temperature gradient exists in the reforming reactor, resulting in significant variation of the gas temperature and reaction rate along the reforming tube. The reduction of the catalyst layer length induces a decrease in H2 (hydrogen) concentration as well as pressure loss. An increased number of tubes leads to better system efficiency owing to the enhanced heat transfer to the reforming tube. Consequently, to improve the system efficiency and reduce the pressure loss, an increase in heat transfer area and decrease in catalyst layer length should be essential design considerations. - Highlights: • A numerical study for the design on a steam reforming reactor is investigated. • The gas concentrations change significantly with variations in the GHSV and input heat capacity. • The reduction of the catalyst layer length induces a decrease in H2 concentration as well as pressure loss. • An increased number of tubes leads to better system efficiency owing to the enhanced heat transfer to reforming tube

  9. Study on a methane-steam reformer by high-temperature helium

    International Nuclear Information System (INIS)

    This report concerns the preliminary study on a methane-steam reformer by high-temperature helium, for which the high-temperature heat exchanger loop, previously reported at the BNES conference on the High-Temperature Reactor and Process Applications in 1974, was reconstructed and redesigned. The loop was designed for use in basic research on methane-steam reforming using high-temperature helium to develop a reformer for a nuclear complex producing iron and steel. As in the case of the high-temperature heat exchanger, the Iron and Steel Institute of Japan provided an outline for the research and IHI undertook its execution, including both the design and construction of the loop. The purpose of the research is to conduct studies on reformed gas production and permeation of hydrogen contained in the reformed gas through heat-resisting alloys. The primary coolant used was helium at a maximum pressure of 6kg/cm2(g) and maximum temperature of 10100C at the reformer inlet. Reduction gas reformed in the secondary side had a maximum pressure of 4kg/cm2(g) and maximum temperature of 9250C at the reformer outlet. (author)

  10. Steam and CO2 reforming of methane over a Ru/ZrO2 catalyst

    DEFF Research Database (Denmark)

    Jakobsen, Jon Geest; Jørgensen, T.L.; Chorkendorff, Ib;

    2010-01-01

    The kinetics of methane steam reforming over a Ru/ZrO2 catalyst was studied at 1.3 bar total pressure and in the temperature range 425-575 degrees C. These data were fitted by combining a reactor model with a series of kinetic models. The best fit was obtained by a model with methane dissociative...

  11. Renewable hydrogen: carbon formation on Ni and Ru catalysts during ethanol steam-reforming

    DEFF Research Database (Denmark)

    Rass-Hansen, Jeppe; Christensen, Christina Hviid; Sehested, J.;

    2007-01-01

    Biomass is probably the only realistic green and sustainable carbonaceous alternative to fossil fuels. By degradation and fermentation, it can be converted into bioethanol, which is a chemical with a range of possible applications. In this study, the catalytic steam-reforming of ethanol for the...

  12. Design of a steam reforming system to be connected to the HTTR

    International Nuclear Information System (INIS)

    Top priority objective for developing the first heat utilization system to be connected to the HTTR is to demonstrate technical feasibility of a nuclear process heat utilization system for production of hydrogen for the first time in the world. Major issues to be resolved for coupling the heat utilization system to the HTTR are 1)to develop safety philosophy for reasonably and reliably ensuring safety of the nuclear reactor, 2)to develop control design concept for the total system of the nuclear reactor and heat utilization system because thermal dynamics of endothermic chemical reactor to be heated by nuclear heat is much different from the nuclear reactor, 3)to develop helium-heated components and 4)to develop enhanced hydrogen production technologies for achieving competitiveness to a fossil-fired plant. A steam reforming hydrogen production system was studied as one of the first priority candidates for an HTTR-heat utilization system due to matured technology in fossil-fired plants and since technical solutions demonstrated by the coupling of the steam reforming system to the HTTR will contribute to all other hydrogen production systems. Basic design philosophy for the HTTR-steam reforming system is that the steam reforming plant downstream of an intermediate secondary helium loop is designed at the same safety level as fossil-fired plants and therefore the secondary helium loop was selected as a safety barrier to the HTTR nuclear reactor. (J.P.N.)

  13. First-principles investigations of the Ni3Sn alloy at steam reforming conditions

    DEFF Research Database (Denmark)

    Saadi, Souheil; Hinnemann, Berit; Helveg, Stig;

    2009-01-01

    The structure and surface composition of a Ni3Sn alloy at conditions relevant for the steam reforming reaction was investigated using density functional theory calculations. Both the flat Ni3Sn [1 0 (1) over bar 0] surface and a surface with steps in the closed packed direction [1 0 (1) over bar 0...

  14. Thermal analysis of cylindrical natural-gas steam reformer for 5 kW PEMFC

    Science.gov (United States)

    Jo, Taehyun; Han, Junhee; Koo, Bonchan; Lee, Dohyung

    2016-01-01

    The thermal characteristics of a natural-gas based cylindrical steam reformer coupled with a combustor are investigated for the use with a 5 kW polymer electrolyte membrane fuel cell. A reactor unit equipped with nickel-based catalysts was designed to activate the steam reforming reaction without the inclusion of high-temperature shift and low-temperature shift processes. Reactor temperature distribution and its overall thermal efficiency depend on various inlet conditions such as the equivalence ratio, the steam to carbon ratio (SCR), and the fuel distribution ratio (FDR) into the reactor and the combustor components. These experiments attempted to analyze the reformer's thermal and chemical properties through quantitative evaluation of product composition and heat exchange between the combustor and the reactor. FDR is critical factor in determining the overall performance as unbalanced fuel injection into the reactor and the combustor deteriorates overall thermal efficiency. Local temperature distribution also influences greatly on the fuel conversion rate and thermal efficiency. For the experiments, the operation conditions were set as SCR was in range of 2.5-4.0 and FDR was in 0.4-0.7 along with equivalence ratio of 0.9-1.1; optimum results were observed for FDR of 0.63 and SCR of 3.0 in the cylindrical steam reformer.

  15. FLUIDIZED BED STEAM REFORMING FOR TREATMENT AND IMMOBILIZATION OF LOW-ACTIVITY WASTE

    Energy Technology Data Exchange (ETDEWEB)

    HEWITT WM

    2011-04-08

    This report is one of four reports written to provide background information regarding immobilization technologies remaining under consideration for supplemental immobilization of Hanford's low-activity waste. This paper provides the reader a general understanding of fluidized bed steam reforming and its possible application to treat and immobilize Hanford low-activity waste.

  16. Modeling and simulation of an isothermal reactor for methanol steam reforming

    Directory of Open Access Journals (Sweden)

    Raphael Menechini Neto

    2014-04-01

    Full Text Available Due to growing electricity demand, cheap renewable energy sources are needed. Fuel cells are an interesting alternative for generating electricity since they use hydrogen as their main fuel and release only water and heat to the environment. Although fuel cells show great flexibility in size and operating temperature (some models even operate at low temperatures, the technology has the drawback for hydrogen transportation and storage. However, hydrogen may be produced from methanol steam reforming obtained from renewable sources such as biomass. The use of methanol as raw material in hydrogen production process by steam reforming is highly interesting owing to the fact that alcohol has the best hydrogen carbon-1 ratio (4:1 and may be processed at low temperatures and atmospheric pressures. They are features which are desirable for its use in autonomous fuel cells. Current research develops a mathematical model of an isothermal methanol steam reforming reactor and validates it against experimental data from the literature. The mathematical model was solved numerically by MATLAB® and the comparison of its predictions for different experimental conditions indicated that the developed model and the methodology for its numerical solution were adequate. Further, a preliminary analysis was undertaken on methanol steam reforming reactor project for autonomous fuel cell.

  17. Fluidized Bed Steam Reforming For Treatment And Immobilization Of Low-Activity Waste

    International Nuclear Information System (INIS)

    This report is one of four reports written to provide background information regarding immobilization technologies remaining under consideration for supplemental immobilization of Hanford's low-activity waste. This paper provides the reader a general understanding of fluidized bed steam reforming and its possible application to treat and immobilize Hanford low-activity waste.

  18. Synergetic mechanism of methanol–steam reforming reaction in a catalytic reactor with electric discharges

    International Nuclear Information System (INIS)

    Highlights: • Methanol–steam reforming was performed on Cu catalysts under an electric discharge. • Discharge had a synergetic effect on the catalytic reaction for methanol conversion. • Discharge lowered the temperature for catalyst activation or light off. • Discharge controlled the yield and selectivity of species in a reforming process. • Adsorption triggered by a discharge was a possible mechanism for a synergetic effect. - Abstract: Methanol–steam reforming was performed on Cu/ZnO/Al2O3 catalysts under an electric discharge. The discharge occurred between the electrodes where the catalysts were packed. The electric discharge was characterized by the discharge voltage and electric power to generate the discharge. The existence of a discharge had a synergetic effect on the catalytic reaction for methanol conversion. The electric discharge provided modified reaction paths resulting in a lower temperature for catalyst activation or light off. The discharge partially controlled the yield and selectivity of species in a reforming process. The aspect of control was examined in view of the reaction kinetics. The possible mechanisms for the synergetic effect between the catalytic reaction and electric discharge on methanol–steam reforming were addressed. A discrete reaction path, particularly adsorption triggered by an electric discharge, was suggested to be the most likely mechanism for the synergetic effect. These results are expected to provide a guide for understanding the plasma–catalyst hybrid reaction

  19. Syngas production via methane steam reforming with oxygen: plasma reactors versus chemical reactors

    International Nuclear Information System (INIS)

    Steam reforming with oxygen (SRO) is a combination of non-catalytic partial oxidation and steam reforming of methane, industrially used for syngas production. There are several models of the chemical reactors used for this purpose but in the last decade a new direction has developed - plasma devices. The aim of the present paper is to make a comparative analysis between the autothermal reformers, including their improved variants, and the plasma reactors. The study is conceived in terms of advantages and disadvantages coming from the exploitation parameters, methane conversion, selectivity, energy efficiency and investment costs. Although SRO by means of chemical reactors may be the most efficient, plasma reactors represent an incisive approach by their simplicity, compactness and low price. (author)

  20. Effect of microchannel structure on the reaction performance of methanol steam reforming

    International Nuclear Information System (INIS)

    Highlights: • Effect of microchannel cross-section and distribution on MSR are investigated. • Microchannel distribution shows much more influence on reaction performance. • SLDR and ELR with rectangular cross-section present better reaction performance. • DLSR and EUU with tooth cross-section have better reaction performance. • Equal-distribution of microchannels present the best reaction performance. - Abstract: Methanol steam reforming inside microchannel reactors is regarded as one of effective methods for supplying hydrogen for fuel cells. Microchannel structure plays an important role on the reaction performance of methanol steam reforming. Parallel and uniform-distributed microchannels with rectangular cross-section are generally adopted. In this work, two kinds of microchannel cross-sections and four kinds of microchannel distributions are selected to investigate the effect of microchannel structure on the reaction performance of methanol steam reforming. The result indicates that microchannel distribution shows much more influences on the reaction performance of methanol steam reforming than the microchannel cross-section. Sparse-distribution in the Left direction and Dense-distribution in the Right direction (SLDR) as well as Equal-distribution in the Left–Right direction (ELR) with rectangular cross-section present relatively good reaction performances, whereas Dense-distribution in the Left direction and Sparse-distribution in the Right direction (DLSR) as well as Equal-distribution in the Upside–Underside direction (EUU) with tooth cross-section have relatively good performances. ELR presents the best reaction performances of methanol steam reforming among all the investigated microchannel structures, whether rectangular or tooth cross-section

  1. Bench Scale Test of Absorption Slurry-ice Maker

    Science.gov (United States)

    Sasao, Hiroyuki; Yoshida, Takashi

    Slurry ice system is desirable as cold heat source for air conditioning, because it requires less conveyance power or less pipe size. On the other hand, recently absorption refrigerator is reevaluated because it can utilize various types of waste heat and it does not use fluorocarbon refrigerant. But it had been regarded to be difficult to make ice by absorption refrigerator because the refrigerant is water. However making slurry ice is possible, of cource, if the slurry ice generated by partial freezing of water is continuously taken away from the evaporator. This method was certified experimentally with a bench scale model. For ice making continuously, ice had not to be frozen stiff at water surface or inside wall of the evaporator. Then refrigerant water in the evaporator was raised swirl flow. And inside wall of the evaporator was finished by water repellent coating, and heated from outside wall. This slurry ice was adaptable to hydraulic transportation, because ice was needle crystal with about 5 mm length and ice temperature was 0°C.

  2. 100 Area groundwater biodenitrification bench-scale treatability study procedures

    Energy Technology Data Exchange (ETDEWEB)

    Peyton, B.M.; Martin, K.R.

    1993-05-01

    This document describes the methodologies and procedures for conducting the bench-scale biodenitrification treatability tests at Pacific Northwest Laboratory{sup a} (PNL). Biodenitrification is the biological conversion of nitrate and nitrite to gaseous nitrogen. The tests will use statistically designed batch studies to determine if biodenitrification can reduce residual nitrate concentrations to 45 mg/L, the current maximum contaminant level (MCL). These tests will be carried out in anaerobic flasks with a carbon source added to demonstrate nitrate removal. At the pilot scale, an incremental amount of additional carbon will be required to remove the small amount of oxygen present in the incoming groundwater. These tests will be conducted under the guidance of Westinghouse Hanford Company (WHC) and the 100-HR-3 Groundwater Treatability Test Plan (DOE/RL-92-73) and the Treatability Study Program Plan (DOE/RL-92-48) using groundwater from 100-HR-3. In addition to the procedures, requirements for safety, quality assurance, reporting, and schedule are given. Appendices include analytical procedures, a Quality Assurance Project Plan, a Health and Safety Plan, and Applicable Material Data Safety Sheets. The procedures contained herein are designed specifically for the 100-HR-3 Groundwater Treatability Test Plan, and while the author believes that the methods described herein are scientifically valid, the procedures should not be construed or mistaken to be generally applicable to any other treatability study.

  3. Kinetic Studies on State of the Art Solid Oxide Cells – A Comparison between Hydrogen/Steam and Reformate Fuels

    DEFF Research Database (Denmark)

    Njodzefon, Jean-Claude; Graves, Christopher R.; Mogensen, Mogens Bjerg;

    2015-01-01

    reformate fuels hydrogen/carbon-dioxide and hydrogen/methane/steam. It was found that the kinetics at the fuel electrode were exactly the same in both reformates. The hydrogen/steam fuel displayed slightly faster kinetics than the reformate fuels. Furthermore the gas conversion impedance in the hydrogen....../steam fuel split into two processes with opposing temperature behavior in the reformate fuels. An 87.5% reduction in active electrode area diminishes the gas conversion impedance in the hydrogen/steam fuel at high fuel flow rates. In both reformates, the second and third lowest frequency processes merged...... into a single process as the gas conversion was reduced. The SOC with finer electrode microstructure displayed improved kinetics....

  4. Study on methane-steam reformer heated by high temperature helium

    International Nuclear Information System (INIS)

    A joint study on the performance characteristics of a methane-steam reformer heated by high temperature helium was conducted by the Iron and Steel Institute of Japan and IHI, using the high temperature heat exchanger loop that was previously reported in Ishikawajima-Harima Engineering Review (Vol. 15 No. 3, May 1975) and modified this time for the study. After surveying the technical problems of reducing gas producing units for nuclear steelmaking, it was decided that the objects of the study should be reducing gas production by means of helium heating and the permeation of hydrogen, contained in the reformed gas, through the reformer tube in operation. The following results were obtained. (1) A good agreement was attained between theoretical predictions and experimental determinations of reforming characteristics under widely varying conditions of operation, so that a satisfactory basis for designing commercial plants has been constructed. (2) The hydrogen permeation characteristics through the reformer tube for the actual reducing gas atmosphere were established experimentally in the methane-steam reforming test. The data obtained can contribute much to the design of reducing gas producing units for nuclear steelmaking. (auth.)

  5. The Engine of Reform Gathers Steam: Kentucky Starts from Scratch.

    Science.gov (United States)

    Harrington-Lueker, Donna

    1990-01-01

    Charged with overhauling the state's educational system, the Kentucky General Assembly last spring devised a landmark reform scheme that mandates site-based management, abolishes the existing state board of education, and institutes an ambitious system of rewards and sanctions aimed at holding schools accountable for student performance. A sidebar…

  6. Steam reforming of toluene as model compound of biomass pyrolysis tar for hydrogen

    International Nuclear Information System (INIS)

    Steam reforming of tar during biomass pyrolysis for hydrogen will not only avoid frequent equipment shutdown for maintenance and repair but also increase hydrogen yield. In this paper, the effects of temperature and steam/carbon molar ration on steam reforming of toluene as model compound of tar was studied by simulation of thermodynamic equilibrium and experiments using Ni/cordierite catalyst in a fixed bed reactor. The results of thermodynamic simulations indicate that the S/C molar ratio of 2 and the temperature range from 1023 K to 1173 K provide favorable operating conditions for steam reforming of toluene in order to get high hydrogen productivity. These operating parameters were adopted in the experiments using Ni/cordierite catalyst in a fixed bed reactor. H2 content remains about 66 mol% and slightly varies with the increasing temperature. Conversion efficiency of toluene increases with temperature, reaching 94.1% at 1173 K. The simulation was improved in order to be closer to experimental results. It is found that only a very small amount of toluene did not participate in the reaction. In the aromatic hydrocarbons of reactive system, benzene and naphthalene were the main products and the proportion of naphthalene decreases with increasing temperature while that of benzene increases.

  7. Evaluation of the feasibility of ethanol steam reforming in a molten carbonate fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Cavallaro, S. [Universita di Messina (Italy); Passalacqua, E.; Maggio, G.; Patti, A.; Freni, S. [Istituto CNR-TAE, Messina (Italy)

    1996-12-31

    The molten carbonate fuel cells (MCFCs) utilizing traditional fuels represent a suitable technological progress in comparison with pure hydrogen-fed MCFCs. The more investigated fuel for such an application is the methane, which has the advantages of low cost and large availability; besides, several authors demonstrated the feasibility of a methane based MCFC. In particular, the methane steam-reforming allows the conversion of the fuel in hydrogen also inside the cell (internal reforming configuration), utilizing the excess heat to compensate the reaction endothermicity. In this case, however, both the catalyst and the cell materials are subjected to thermal stresses due to the cold spots arising near to the reaction sites MCFC. An alternative, in accordance with the recent proposals of other authors, may be to produce hydrogen from methane by the partial oxidation reaction, rather than by steam reforming. This reaction is exothermic ({Delta}H{degrees}=-19.1 kJ/mol H{sub 2}) and it needs to verify the possibility to obtain an acceptable distribution of the temperature inside the cell. The alcohols and, in particular, methanol shows the gas reformed compositions as a function of the steam/ethanol molar ratio, ranging from 1.0 to 3.5. The hydrogen production enhances with this ratio, but it presents a maximum at S/EtOH of about 2.0. Otherwise, the increase of S/EtOH depresses the production of CO and CH{sub 4}, and ethanol may be a further solution for the hydrogen production inside a MCFC. In this case, also, the reaction in cell is less endothermic compared with the methane steam reforming with the additional advantage of a liquid fuel more easily storable and transportable. Aim of the present work is to perform a comparative evaluation of the different solutions, with particular reference to the use of ethanol.

  8. Application of Flexible Micro Temperature Sensor in Oxidative Steam Reforming by a Methanol Micro Reformer

    OpenAIRE

    Yi-Man Lo; Chi-Chung Chang; Chia-Chieh Shen; Shuo-Jen Lee; Chi-Yuan Lee; Chuin-Tih Yeh

    2011-01-01

    Advances in fuel cell applications reflect the ability of reformers to produce hydrogen. This work presents a flexible micro temperature sensor that is fabricated based on micro-electro-mechanical systems (MEMS) technology and integrated into a flat micro methanol reformer to observe the conditions inside that reformer. The micro temperature sensor has higher accuracy and sensitivity than a conventionally adopted thermocouple. Despite various micro temperature sensor applications, integrated ...

  9. Thermodynamic analysis of hydrogen production by steam and autothermal reforming of soybean waste frying oil

    International Nuclear Information System (INIS)

    Highlights: • Thermodynamic analysis of steam and autothermal reforming of soybean frying oil. • Soybean frying oil is considered as a mixture of triglycerides. • Coke formation is avoided by increasing the temperature and/or the S/C ratio. • Optimum steam reforming conditions are 650–850 °C and S/C ratio around 5. • Optimum autothermal conditions are 600–800 °C, S/C of 3–5 and O/C of 0.391–0.455. - Abstract: Hydrogen production via steam and autothermal reforming of soybean waste frying oils (WFOs) is thermodynamically investigated via the Gibbs free energy minimization method. The thermodynamic optimum conditions are determined to maximize hydrogen production while minimizing the methane and carbon monoxide contents and coke formation. Equilibrium calculations are performed at atmospheric pressure over a wide range of temperatures (400–1200 °C), steam-to-WFO ratios (S/C: 1–15) and oxygen-to-WFO ratios (O/C: 0.0–2.0). The baseline case used for the study considers soybean WFO after 8 h of use (WFO8). The influence of frying time on the performance of reforming reactors is also discussed. The results show that the optimum conditions for steam reforming can be achieved at reforming temperatures between 650 °C and 850 °C and at a steam to carbon molar (S/C) ratio of approximately 5. The recommended operation conditions for the SR of WFO8 are proposed to be T = 650 °C and S/C ratio = 5. Under these conditions, a hydrogen yield of 169.83 mol/kg WFO8 can be obtained with a CO concentration in the SG of 3.91% and trace CH4 (0.03%), without the risk of coke formation. Hydrogen production from autothermal systems can be optimized at temperatures of 600–800 °C, S/C ratios of 3–5, and O/C ratios of 0.0–0.5. Under these conditions, thermoneutrality is obtained with O/C ratios of 0.391–0.455. The recommended thermoneutral conditions are S/C = 5, T = 600 °C and O/C = 0.453. Under these conditions, 146.45 mol H2/kg WFO8 can be produced

  10. Design of a Compact and Versatile Bench Scale Tubular Reactor

    Directory of Open Access Journals (Sweden)

    R. Prasad

    2009-06-01

    Full Text Available A compact and versatile laboratory tubular reactor has been designed and fabricated keeping in view of reducing capital cost and minimising energy consumption for gas/vapor-phase heterogeneous catalytic reactions. The reactor is consisted of two coaxial corning glass tubes with a helical coil of glass tube in between the coaxial tubes serving as vaporiser and pre-heater, the catalyst bed is in the inner tube. A schematic diagram of the reactor with detailed dimensions and working principles are described. The attractive feature of the reactor is that the vaporiser, pre-heater and fixed bed reactor are merged in a single compact unit. Thus, the unit minimises separate vaporiser and pre-heater, also avoids separate furnaces used for them and eliminate auxiliary instrumentation such as temperature controller etc. To demonstrate the system operation and illustrate the key features, catalyst screening data and the efficient collection of complete, and accurate intrinsic kinetic data are provided for oxidation of CO over copper chromite catalyst. CO oxidation is an important reaction for auto-exhaust pollution control. The suitability of the versatile nature of the reactor has been ascertained for catalytic reactions where either volatile or vaporizable feeds can be introduced to the reaction zone, e.g. oxidation of iso-octane, reduction of nitric oxide, dehydrogenation of methanol, ethanol and iso-propanol, hydrogenation of nitrobenzene to aniline, etc. Copyright (c 2009 by BCREC. All Rights reserved.[Received: 10 February 2009, Accepted: 9 May 2009][How to Cite: R. Prasad, G. Rattan. (2009. Design of a Compact and Versatile Bench Scale Tubular Reactor. Bulletin of Chemical Reaction Engineering and Catalysis, 4(1: 5-9.  doi:10.9767/bcrec.4.1.1250.5-9][How to Link/ DOI: http://dx.doi.org/10.9767/bcrec.4.1.1250.5-9

  11. Bench-scale co-processing economic assessment. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Gala, H.B.; Marker, T.L.; Miller, E.N.

    1994-11-01

    The UOP Co-Processing scheme is a single-stage slurry catalyzed process in which petroleum vacuum resid and coal are simultaneously upgraded to a high-quality synthetic oil. A highly active dispersed catalyst has been developed which enables the operation of the co-processing unit at relatively moderate and high temperatures and relatively high pressure. Under the current contract, a multi-year research program was undertaken to study the technical and economic feasibility of this technology. All the contractual tasks were completed. Autoclave experiments were carried out to evaluate dispersed vanadium catalysts, molybdenum catalysts, and a less costly UOP-proprietary catalyst preparation technique. Autoclave experiments were also carried out in support of the continuous pilot plant unit operation and to study the effects of the process variables (pressure, temperature, and metal loading on the catalyst). A total of 24 continuous pilot plant runs were made. Research and development efforts during the pilot plant operations were concentrated on addressing the cost effectiveness of the UOP single-stage slurry catalyzed co-processing concept based on UOP experience gained in the previous DOE contract. To this end, effect of catalyst metal concentration was studied and a highly-active Mo-based catalyst was developed. This catalyst enabled successful long-term operation (924 hours) of the continuous bench-scale plant at highly severe operating conditions of 3,000 psig, 465{degree}C temperature, and 2:1 resid-to-MAF (moisture- and ash-free) coal ratio with 0.1 wt % active metal. The metal loading of the catalyst was low enough to consider the catalyst as a disposable slurry catalyst. Also, liquid recycle was incorporated in the pilot plant design to increase the, reactor back mixing and to increase the flow of liquid through the reactor (to introduce turbulence in the reactor) and to represent the design of a commercial-scale reactor.

  12. Bench-scale studies with mercury contaminated SRS soil

    International Nuclear Information System (INIS)

    Bench-scale studies with mercury contaminated soil were performed at the SRTC to determine the optimum waste loading obtainable in the glass product without sacrificing durability, leach resistance, and processability. Vitrifying this waste stream also required offgas treatment for the capture of the vaporized mercury. Four soil glasses with slight variations in composition were produced, which were capable of passing the Product Consistency Test (PCT) and the Toxicity Characteristic Leaching Procedure (TCLP). The optimum glass feed composition contained 60 weight percent soil and produced a soda-lime-silica glass when melted at 1,350 C. The glass additives used to produce this glass were 24 weight percent Na2CO3 and 16 weight percent CaCO3. Volatilized mercury released during the vitrification process was released to the proposed mercury collection system. The proposed mercury collection system consisted of quartz and silica tubing with a Na2S wash bottle followed by a NaOH wash bottle. Once in the system, the volatile mercury would pass through the wash bottle containing Na2S, where it would be converted to Hg2S, which is a stable form of mercury. However, attempts to capture the volatilized mercury in a Na2S solution wash bottle were not as successful as anticipated. Maximum mercury captured was only about 3.24% of the mercury contained in the feed. Mercury capture efforts then shifted to condensing and capturing the volatilized mercury. These attempts were much more successful at capturing the volatile mercury, with a capture efficiency of 34.24% when dry ice was used to pack the condenser. This captured mercury was treated on a mercury specific resin after digestion of the volatilized mercury

  13. Destruction of UST organics and nitrates, polymeric organic wastes, and chlorocarbon solvents by steam reforming

    International Nuclear Information System (INIS)

    In support of the UST, WeDID, VOC/Non-Arid, and VOC/Arid, and VOC/Arid Integrated Demonstrations, organic contaminants and nitrates in Hanford Underground Storage Tank (UST) wastes, polymeric organics in weapon components, and chlorocarbon soil contaminants have been destroyed by exposure to high-temperature steam during bench tests with a quartz reactor and full-scale tests that used the Synthetica Detoxifier, a commercial one-ton-per-day steam reforming waste destruction system. Reactivation of Granular Activated Carbon (GAC) in the Detoxifier and Thermal Gravimetric Analyses (TGA) of the decomposition of sodium nitrate have also been performed

  14. Safety aspect of high temperature nuclear reactor application for natural gas steam reforming

    International Nuclear Information System (INIS)

    An assessment of the safety aspect of high temperature nuclear reactor application for natural gas steam reforming has been carried out. The basic safety aspect associated with nuclear coupling to chemical process is to prevent the release of radioactive materials to the environment and or the chemical process. In utilizing nuclear heat for chemical process, intermediate heat exchanger (IHX) is used as an interface that separates nuclear and non nuclear zones. IHX is helium-helium heat exchanger in which the primary helium (905oC) coming out from the reactor, and transfer its heat to the secondary helium gas (890oC). To prevent possible release of radioactive materials from nuclear zone, balanced pressure is applied. The pressure of chemical process (4.5 MPa) is designed to be higher than the pressure of secondary helium (4.1 MPa) or primary helium (4 MPa). The design of balance pressure and the use of IHX cause some inferior condition of the nuclear heated reformer since the lower temperature (~800oC) reaches catalyst tube of reformer. This condition gives impact on lower thermal efficiency (~50%) compared to the fossil-fuelled plant (80-85%). Some modification in design and operation, such as: selecting the bayonet type of reformer equipped with orifice baffle, and enhancing heat utilization, can improve the lack of condition and are capable to increase the thermal efficiency of nuclear heated natural gas steam reformer to reach about 78%. (author)

  15. Steam reforming of methane using double-walled reformer tubes containing high-temperature thermal storage Na2CO3/MgO composites for solar fuel production

    International Nuclear Information System (INIS)

    Double-walled reactor tubes containing thermal storage materials based on the molten carbonate salts—100 wt% Na2CO3 molten salt, 90 wt% Na2CO3/10 wt% MgO and 80 wt% Na2CO3/20 wt% MgO composite materials—were studied for the performances of the reactor during the heat charging mode, while those of methane reforming with steam during heat discharging mode for solar steam reforming. The variations in the temperatures of the catalyst and storage material, methane conversion, duration of reforming for obtaining high levels of methane conversion (>90%), higher heating value (HHV) power of reformed gas and efficiency of the reactor tubes were evaluated for the double-walled reactor tubes and a single-wall reactor tube without the thermal storage. The results for the heat charging mode indicated that the composite thermal storage could successfully store the heat transferred from the exterior wall of the reactor in comparison to the pure molten-salt. The double-walled reactor tubes with the 90 wt% Na2CO3/10 wt% MgO composite material was the most desirable for steam reforming of methane to realize large HHV amounts of reformed gas and higher efficiencies during heat-discharging mode. - Highlights: • Double-walled reactor tubes containing high-temperature thermal storage are examined for solar steam reforming. • The reactor performances were evaluated for the heat charging, while those of steam reforming for heat discharging. • The 90 wt% Na2CO3/10 wt% MgO composite material was the most desirable for steam reforming of methane by the reactor tubes

  16. A Comparative Study between Co and Rh for Steam Reforming of Ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Karim, Ayman M.; Su, Yu; Sun, Junming; Yang, Cheng; Strohm, James J.; King, David L.; Wang, Yong

    2010-06-01

    Rh and Co-based catalyst performance was compared for steam reforming of ethanol under conditions suitable for industrial hydrogen production. The reaction conditions were varied to elucidate the differences in reaction pathways on both catalysts. On Co/ZnO, CH4 is a secondary product formed through the methanation reaction, while it is produced directly by ethanol decomposition on Rh. The difference in the reaction mechanism is shown to favor Co-based catalysts for selective hydrogen production under elevated system pressures (up to 15 bar) of industrial importance. The carbon deposition rate was also studied, and we show that Co is more prone to coking and catalyst failure. However, the Co/ZnO catalyst can be regenerated, by mild oxidation, despite the high carbon deposition rate. We conclude that Co/ZnO is a more suitable catalyst system for steam reforming of ethanol due to the low methane selectivity, low cost and possibility of regeneration with mild oxidation.

  17. Effect of ZnO facet on ethanol steam reforming over Co/ZnO

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Ning; Zhang, He; Davidson, Stephen; Sun, Junming; Wang, Yong

    2016-01-05

    The effects of ZnO facets on ethanol steam reforming (ESR) were investigated over Co/ZnO catalysts synthesized using ZnO with different fractions of (10-10) non-polar facet. Co supported on ZnO with a higher fraction of (10-10) non-polar facet shows higher C-C cleavage activity and higher selectivity to CO2 (lower selectivity to CO) compared with Co supported on ZnO with less (10-10) non-polar facet exposed. The improved ethanol steam reforming performances are attributed to the high fraction of metallic Co stabilized by the ZnO (10-10) non-polar facet, which enhanced C-C cleavage and water-gas-shift (WGS) activities.

  18. Task 19 - Sampling, Analysis, and Vitrification Study for Thermochem's Steam Reformer Treatment Technology

    Energy Technology Data Exchange (ETDEWEB)

    Lillemoen, C.M.; McCollor, D.P.; Qi Sun

    1998-11-01

    The overall objective of the project is to provide support to Thermochem, Inc., in the demonstration of the steam reformer treatment technology to treat LLMW. Within this program, specific objectives include the following: (1) Analyze cerium, chlorine, and fluorine concentrations in samples from the pilot-scale steam reformer tests to determine partitioning of these elements, mass balances, and changes in concentration with time. (2) Perform experimental characterization of temperature--viscosity profiles to aid in determining vitrification viability for long-term stabilization. Additionally, calculations of viscosity will be performed for several blend combinations to complement the experimentally determined values. (3) Conduct leachability tests on the vitrified slags to aid in determining if product leachability falls within EPA guidelines and to assess the suitability of the vitrified material for long-term disposal.

  19. Membrane steam reforming of natural gas for hydrogen production by utilization of medium temperature nuclear reactor

    International Nuclear Information System (INIS)

    The assessment of steam reforming process with membrane reactor for hydrogen production by utilizing of medium temperature nuclear reactor has been carried out. Difference with the conventional process of natural gas steam reforming that operates at high temperature (800-1000°C), the process with membrane reactor operates at lower temperature (~500°C). This condition is possible because the use of perm-selective membrane that separate product simultaneously in reactor, drive the optimum conversion at the lower temperature. Besides that, membrane reactor also acts the role of separation unit, so the plant will be more compact. From the point of nuclear heat utilization, the low temperature of process opens the chance of medium temperature nuclear reactor utilization as heat source. Couple the medium temperature nuclear reactor with the process give the advantage from the point of saving fossil fuel that give direct implication of decreasing green house gas emission. (author)

  20. Parametric study of hydrogen production from ethanol steam reforming in a membrane microreactor

    OpenAIRE

    M. de-Souza; G. M. Zanin; F. F. Moraes

    2013-01-01

    Microreactors are miniaturized chemical reaction systems, which contain reaction channels with characteristic dimensions in the range of 10-500 µm. One possible application for microreactors is the conversion of ethanol to hydrogen used in fuel cells to generate electricity. In this paper a rigorous isothermal, steady-state two-dimensional model was developed to simulate the behavior of a membrane microreactor based on the hydrogen yield from ethanol steam reforming. Furthermore, this membran...

  1. Methanol Steam Reforming Promoted by Molten Salt-Modified Platinum on Alumina Catalysts

    OpenAIRE

    Kusche, Matthias; Agel, Friederike; Ní Bhriain, Nollaig; Kaftan, Andre; Laurin, Mathias; Libuda, Jörg; Wasserscheid, Peter

    2014-01-01

    We herein describe a straight forward procedure to increase the performance of platinum-on-alumina catalysts in methanol steam reforming by applying an alkali hydroxide coating according to the “solid catalyst with ionic liquid layer” (SCILL) approach. We demonstrate by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and temperature-programmed desorption (TPD) studies that potassium doping plays an important role in the catalyst activation. Moreover, the hygroscopic natur...

  2. MATHEMATICAL MODELLING OF METHANE STEAM REFORMING IN A MEMBRANE REACTOR: AN ISOTHERMIC MODEL

    OpenAIRE

    ASSAF E.M.; JESUS C.D.F.; J.M. ASSAF

    1998-01-01

    A mathematical modelling of one-dimensional, stationary and isothermic membrane reactor for methane steam reforming was developed to compare the maximum yield for methane conversion in this reactor with that in a conventional fixed-bed reactor. Fick's first law was used to describe the mechanism of hydrogen permeation. The variables studied include: reaction temperature, hydrogen feed flow rate and membrane thickness. The results show that the membrane reactor presents a higher methane conver...

  3. MATHEMATICAL MODELLING OF METHANE STEAM REFORMING IN A MEMBRANE REACTOR : AN ISOTHERMIC MODEL

    OpenAIRE

    ASSAF E.M.; JESUS C.D.F.; J.M. ASSAF

    1998-01-01

    A mathematical modelling of one-dimensional, stationary and isothermic membrane reactor for methane steam reforming was developed to compare the maximum yield for methane conversion in this reactor with that in a conventional fixed-bed reactor. Fick's first law was used to describe the mechanism of hydrogen permeation. The variables studied include: reaction temperature, hydrogen feed flow rate and membrane thickness. The results show that the membrane reactor presents a higher methane conver...

  4. Synthesis gas production via hybrid steam reforming of natural gas and bio-liquids

    OpenAIRE

    Balegedde Ramachandran, P.

    2013-01-01

    This thesis deals with (catalytic) steam reforming of bio-liquids for the production of synthesis gas. Glycerol, both crude from the biodiesel manufacturing and refined, and pyrolysis oil are tested as bio-based feedstocks. Liquid bio-based feeds could be preferred over inhomogeneous fibrous solid biomass because of their logistic advantages, better mineral balance, and better processability. Especially the ease of pressurization, which is required for large scale synthesis gas production, is...

  5. Hydrogen Production via Steam Reforming of Ethyl Alcohol over Palladium/Indium Oxide Catalyst

    OpenAIRE

    Tetsuo Umegaki; Yusuke Yamada; Atsushi Ueda; Nobuhiro Kuriyama; Qiang Xu

    2009-01-01

    We report the synergetic effect between palladium and indium oxide on hydrogen production in the steam reforming reaction of ethyl alcohol. The palladium/indium oxide catalyst shows higher hydrogen production rate than indium oxide and palladium. Palladium/indium oxide affords ketonization of ethyl alcohol with negligible by-product carbon monoxide, while indium oxide mainly affords dehydration of ethyl alcohol, and palladium affords decomposition of ethyl alcohol with large amount of by-prod...

  6. Bench-Scale Testing of the Micronized Magnetite Process

    Energy Technology Data Exchange (ETDEWEB)

    Edward R. Torak; Peter J. Suardini

    1997-11-01

    A recent emphasis of the Department of Energy's (DOE's), Coal Preparation Program has been the development of high-efficiency technologies that offer near-term, low-cost improvements in the ability of coal preparation plants to address problems associated with coal fines. In 1992, three cost-shared contracts were awarded to industry, under the first High-Efficiency Preparation (HEP I) solicitation. All three projects involved bench-scale testing of various emerging technologies, at the Federal Energy Technology Center*s (FETC*s), Process Research Facility (PRF). The first HEP I project, completed in mid-1993, was conducted by Process Technology, Inc., with the objective of developing a computerized, on-line system for monitoring and controlling the operation of a column flotation circuit. The second HEP I project, completed in mid-1994, was conducted by a team led by Virginia Polytechnic Institute to test the Mozely Multi-Gravity Separator in combination with the Microcel Flotation Column, for improved removal of mineral matter and pyritic sulfur from fine coal. The last HEP I project, of which the findings are contained in this report, was conducted by Custom Coals Corporation to evaluate and advance a micronized-magnetite-based, fine-coal cycloning technology. The micronized-magnetite coal cleaning technology, also know as the Micro-Mag process, is based on widely used conventional dense-medium cyclone applications, in that it utilizes a finely ground magnetite/water suspension as a separating medium for cleaning fine coal, by density, in a cyclone. However, the micronized-magnetite cleaning technology differs from conventional systems in several ways: ! It utilizes significantly finer magnetite (about 5 to 10 micron mean particle size), as compared to normal mean particle sizes of 20 microns. ! It can effectively beneficiate coal particles down to 500M in size, as compared to the most advanced, existing conventional systems that are limited to a

  7. BENCH-SCALE RECOVERY OF LEAD USING AN ELECTROMEMBRANE/CHELATION PROCESS

    Science.gov (United States)

    This report presents the results of a bench-scale treatability test to investigate key process parameters influencing an innovative chelation electrodeposition process for recovery of lead from contaminated sons. thylenediamine tetraacetic acid (EDTA) and diethylenetriamine penta...

  8. BENCH-SCALE RECOVERY OF LEAD USING AND ELECTRO- MEMBRANE/CHELATION PROCESS

    Science.gov (United States)

    This report presents the results of a bench-scale treatability test to investigate key process parameters influencing an innovative chelation electrodeposition process for recovery of lead from contaminated sons. thylenediamine tetraacetic acid (EDTA) and diethylenetriamine penta...

  9. Parametric study of hydrogen production from ethanol steam reforming in a membrane microreactor

    Directory of Open Access Journals (Sweden)

    M. de-Souza

    2013-06-01

    Full Text Available Microreactors are miniaturized chemical reaction systems, which contain reaction channels with characteristic dimensions in the range of 10-500 µm. One possible application for microreactors is the conversion of ethanol to hydrogen used in fuel cells to generate electricity. In this paper a rigorous isothermal, steady-state two-dimensional model was developed to simulate the behavior of a membrane microreactor based on the hydrogen yield from ethanol steam reforming. Furthermore, this membrane microreactor is compared to a membraneless microreactor. A potential advantage of the membrane microreactor is the fact that both ethanol steam reforming and the separation of hydrogen by a permselective membrane occur in one single microdevice. The simulation results for steam reforming yields are in agreement with experimental data found in the literature. The results show that the membrane microreactorpermits a hydrogen yield of up to 0.833 which is more than twice that generated by the membraneless reactor. More than 80% of the generated hydrogen permeates through the membrane and, due to its high selectivity, the membrane microreactor delivers high-purity hydrogen to the fuel cell.

  10. Studies of potassium-promoted nickel catalysts for methane steam reforming: Effect of surface potassium location

    Science.gov (United States)

    Borowiecki, Tadeusz; Denis, Andrzej; Rawski, Michał; Gołębiowski, Andrzej; Stołecki, Kazimierz; Dmytrzyk, Jaromir; Kotarba, Andrzej

    2014-05-01

    The effect of potassium addition to the Ni/Al2O3 steam reforming catalyst has been investigated on several model systems, including K/Al2O3 with various amounts of alkali promoters (1-4 wt% of K2O), a model catalyst 90%NiO-10%Al2O3 promoted with potassium and a commercial catalyst. The potassium surface state and stability were investigated by means of the Species Resolved Thermal Alkali Desorption method (SR-TAD). The activity of the catalysts in the steam reforming of methane and their coking-resistance were also evaluated. The results reveal that the beneficial effect of potassium addition is strongly related to its location in the catalysts. The catalyst surface should be promoted with potassium in order to obtain high coking-resistant catalysts. Moreover, the catalyst preparation procedure should ensure a direct interaction of potassium with the Al2O3 support surface. Due to the low stability of potassium on θ-Al2O3 this phase is undesirable during the preparation of a stable steam reforming catalyst.

  11. PRODUCTION OF HYDROGEN FROM THE STEAM AND OXIDATIVE REFORMING OF LPG: THERMODYNAMIC AND EXPERIMENTAL STUDY

    Directory of Open Access Journals (Sweden)

    P. P. Silva

    2015-09-01

    Full Text Available AbstractThe objective of this paper was to use a thermodynamic analysis to find operational conditions that favor the production of hydrogen from steam and oxidative reforming of liquefied petroleum gas (LPG. We also analyzed the performance of a catalyst precursor, LaNiO3, in order to compare the performance of the obtained catalyst with the thermodynamic equilibrium predictions. The results showed that it is possible to produce high concentrations of hydrogen from LPG reforming. The gradual increase of temperature and the use of high water concentrations decrease the production of coke and increase the formation of H2. The reaction of oxidative reforming of LPG was more suitable for the production of hydrogen and lower coke formation. Furthermore the use of an excess of water (H2O/LPG =7.0 and intermediate temperatures (973 K are the most suitable conditions for the process.

  12. INVESTIGATION OF FUEL CHEMISTRY AND BED PERFORMANCE IN A FLUIDIZED BED BLACK LIQUOR STEAM REFORMER

    Energy Technology Data Exchange (ETDEWEB)

    Kevin Whitty

    2003-12-01

    The University of Utah project ''Investigation of Fuel Chemistry and Bed Performance in a Fluidized Bed Black Liquor Steam Reformer'' (DOE award number DE-FC26-02NT41490) was developed in response to a solicitation for projects to provide technical support for black liquor and biomass gasification. The primary focus of the project is to provide support for a DOE-sponsored demonstration of MTCI's black liquor steam reforming technology at Georgia-Pacific's paper mill in Big Island, Virginia. A more overarching goal is to improve the understanding of phenomena that take place during low temperature black liquor gasification. This is achieved through five complementary technical tasks: (1) construction of a fluidized bed black liquor gasification test system, (2) investigation of bed performance, (3) evaluation of product gas quality, (4) black liquor conversion analysis and modeling and (5) computational modeling of the Big Island gasifier. Four experimental devices have been constructed under this project. The largest facility, which is the heart of the experimental effort, is a pressurized fluidized bed gasification test system. The system is designed to be able to reproduce conditions near the black liquor injectors in the Big Island steam reformer, so the behavior of black liquor pyrolysis and char gasification can be quantified in a representative environment. The gasification test system comprises five subsystems: steam generation and superheating, black liquor feed, fluidized bed reactor, afterburner for syngas combustion and a flue gas cooler/condenser. The three-story system is located at University of Utah's Industrial Combustion and Gasification Research Facility, and all resources there are available to support the research.

  13. Maximum Hydrogen Production by Autothermal Steam Reforming of Bio-oil With NiCuZnAl Catalyst

    Institute of Scientific and Technical Information of China (English)

    Shi-zhi Yan; Qi Zhai; Quan-xin Li

    2012-01-01

    Autothermal steam reforming (ATR) of bio-oil,which couples the endothermic steam reforming reaction with the exothermic partial oxidation,offers many advantages from a technical and economic point of view.Effective production of hydrogen through ATR of bio-oil was performed at lower temperature with NiCuZnAl catalyst.The highest hydrogen yield from bio-oil reached 64.3% with a nearly complete bio-oil conversion at 600 ℃,the ratio of steam to carbon fed (S/C) of 3 and the oxygen to carbon ratio (O/C) of 0.34.The reaction conditions in ATR including temperature,O/C,S/C and weight hourly space velocity can be used to control both hydrogen yield and products distribution.The comparison between the ATR and common steam reforming of bio-oil was studied.The mechanism of the ATR of bio-oil was also discussed.

  14. Internal steam reforming in solid oxide fuel cells: Status and opportunities of kinetic studies and their impact on modelling

    DEFF Research Database (Denmark)

    Mogensen, David; Grunwaldt, J.-D.; Hendriksen, Peter Vang;

    2011-01-01

    operating conditions, catalyst support material and structure it is critical to transfer this knowledge directly to internal reforming in SOFCs, which is discussed in further detail in this article. There are big differences in the reported kinetic expression for steam reforming over both industrial Ni...... catalysts and SOFC anode materials. Surprisingly, there is a good agreement between measured rates pr. geometric anode area at high operating temperatures, even for very different anodes. Detailed experimental data on the intrinsic steam reforming kinetics of Ni-YSZ are necessary for micro structure SOFC......Solid oxide fuel cells (SOFC) systems with internal steam reforming have the potential to become an economically competitive technology for cogeneration power plants, exploiting its significantly higher electrical efficiency compared to existing technologies. Optimal design and operation of such a...

  15. Preliminary design of steam reformer in out-pile demonstration test facility for HTTR heat utilization system

    International Nuclear Information System (INIS)

    One of the key objectives of HTTR is to demonstrate effectiveness of high-temperature nuclear heat utilization system. Prior to connecting a heat utilization system to HTTR, an out-pile demonstration test is indispensable for the development of experimental apparatuses, operational control and safety technology, and verification of the analysis code of safety assessment. For the first heat utilization system of HTTR, design of the hydrogen production system by steam reforming is going on. We have proposed the out-pile demonstration test plan of the heat utilization system and conducted preliminary design of the test facility. In this report, design of the steam reformer, which is the principal component of the test facility, is described. In the course of the design, two types of reformers are considered. The one reformer contains three reactor tubes and the other contains one reactor tube to reduce the construction cost of the test facility. We have selected the steam reformer operational conditions and structural specifications by analyzing the steam reforming characteristics and component structural strength for each type of reformer. (author)

  16. Sorption enhanced steam reforming of biomass-derived compounds: process and material

    Energy Technology Data Exchange (ETDEWEB)

    He, Li

    2010-07-01

    An attempt has been made to develop a flexible system to produce very pure H{sub 2} with high efficiency from renewable bio-based recourses. First, such model compounds as ethanol, glycerol, sorbitol and glucose, have been tested for H{sub 2} production via sorption enhanced steam reforming (SESR) over Co-Ni/hydrotalcite-like (HTls) derived catalyst and CaO-based CO{sub 2} acceptor. The experimental results show that all of feedstocks, even heavy feedstocks, were able to offer high H{sub 2} purity (97.3approx99.1%) and yield at low steam to carbon (S/C = 1.3approx6) ratio in comparison to the corresponding steam reforming process. In addition, the studied system also presents encouraging potential for improvement of energy efficiency. Chemical looping combustion (CLC) was coupled to the cyclic multi-step SESR process to assist the acceptor regeneration by using multifunctional Pd/Co-Ni/HTls catalyst. With coupling of CLC to SESR, H{sub 2} concentration in the gas effluent of the SESR reactions was still higher than 95 mol% on a dry basis. The assembled CLC-SESR process has inherent high efficiency in H{sub 2} production. (Author)

  17. Numerical analysis of performance of steam reformer of methane reforming hydrogen production system connected with high-temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    Methane conversion rate and hydrogen output are important performance indexes of the steam reformer. The paper presents numerical analysis of performance of the reformer connected with high-temperature gas-cooled reactor HTR-10. Setting helium inlet flow rate fixed, performance of the reformer was examined with different helium inlet temperature, pressure, different process gas temperature, pressure, flow rate, and different steam to carbon ratio. As the range concerned, helium inlet temperature has remarkable influence on the performance, and helium inlet temperature, process gas temperature and pressure have little influence on the performance, and improving process gas flow rate, methane conversion rate decreases and hydrogen output increases, however improving steam to carbon ratio has reverse influence on the performance. (authors)

  18. The role of surface reactions on the active and selective catalyst design for bioethanol steam reforming

    Science.gov (United States)

    Benito, M.; Padilla, R.; Serrano-Lotina, A.; Rodríguez, L.; Brey, J. J.; Daza, L.

    In order to study the role of surface reactions involved in bioethanol steam reforming mechanism, a very active and selective catalyst for hydrogen production was analysed. The highest activity was obtained at 700 °C, temperature at which the catalyst achieved an ethanol conversion of 100% and a selectivity to hydrogen close to 70%. It also exhibited a very high hydrogen production efficiency, higher than 4.5 mol H 2 per mol of EtOH fed. The catalyst was operated at a steam to carbon ratio (S/C) of 4.8, at 700 °C and atmospheric pressure. No by-products, such as ethylene or acetaldehyde were observed. In order to consider a further application in an ethanol processor, a long-term stability test was performed under the conditions previously reported. After 750 h, the catalyst still exhibited a high stability and selectivity to hydrogen production. Based on the intermediate products detected by temperature programmed desorption and reaction (TPD and TPR) experiments, a reaction pathway was proposed. Firstly, the adsorbed ethanol is dehydrogenated to acetaldehyde producing hydrogen. Secondly, the adsorbed acetaldehyde is transformed into acetone via acetic acid formation. Finally, acetone is reformed to produce hydrogen and carbon dioxide, which were the final reaction products. The promotion of such reaction sequence is the key to develop an active, selective and stable catalyst, which is the technical barrier for hydrogen production by ethanol reforming.

  19. The role of surface reactions on the active and selective catalyst design for bioethanol steam reforming

    Energy Technology Data Exchange (ETDEWEB)

    Benito, M. [Instituto de Catalisis y Petroleoquimica (CSIC), C/Marie Curie 2, Campus Cantoblanco, 28049 Madrid (Spain); Ciemat, Av. Complutense 22, 28040 Madrid (Spain); Padilla, R.; Serrano-Lotina, A.; Rodriguez, L.; Daza, L. [Instituto de Catalisis y Petroleoquimica (CSIC), C/Marie Curie 2, Campus Cantoblanco, 28049 Madrid (Spain); Brey, J.J. [Hynergreen Technologies, Av. Buhaira 2, 41018 Sevilla (Spain)

    2009-07-01

    In order to study the role of surface reactions involved in bioethanol steam reforming mechanism, a very active and selective catalyst for hydrogen production was analysed. The highest activity was obtained at 700 C, temperature at which the catalyst achieved an ethanol conversion of 100% and a selectivity to hydrogen close to 70%. It also exhibited a very high hydrogen production efficiency, higher than 4.5 mol H{sub 2} per mol of EtOH fed. The catalyst was operated at a steam to carbon ratio (S/C) of 4.8, at 700 C and atmospheric pressure. No by-products, such as ethylene or acetaldehyde were observed. In order to consider a further application in an ethanol processor, a long-term stability test was performed under the conditions previously reported. After 750 h, the catalyst still exhibited a high stability and selectivity to hydrogen production. Based on the intermediate products detected by temperature programmed desorption and reaction (TPD and TPR) experiments, a reaction pathway was proposed. Firstly, the adsorbed ethanol is dehydrogenated to acetaldehyde producing hydrogen. Secondly, the adsorbed acetaldehyde is transformed into acetone via acetic acid formation. Finally, acetone is reformed to produce hydrogen and carbon dioxide, which were the final reaction products. The promotion of such reaction sequence is the key to develop an active, selective and stable catalyst, which is the technical barrier for hydrogen production by ethanol reforming. (author)

  20. Effect of equilibrium-shift by using lithium silicate in methane steam reforming

    International Nuclear Information System (INIS)

    Equilibrium shifting is considered to be effective for promoting H2 production by methane (CH4) steam reforming. In this study, a packed bed reactor with a mixture of reforming catalyst and CO2 absorbent was used. Lithium silicate (Li4SiO4) was applied as the absorbent, which Toshiba has developed. In the case of Li4SiO4, CO2 emission occurs at considerably lower temperature than in the case of the well-known calcium oxide (CaO) and the reaction between Li4SiO4 and CO2 is highly reversible. This is a report on the relationship between CO2 absorption by Li4SiO4 and the equilibrium-shift effect for steam reforming of CH4. Experiments showed strong influence of temperature on the equilibrium-shift effect. The effect was obvious, which resulted in keeping not only the concentration of H2 at ca. 94 vol% but also that of CO at 0.2 vol%. This result indicates the possibility of dispensing with a CO-shift reactor and simplifying the preferential oxidation reactor, which would improve the conventional H2 production system. (authors)

  1. Thermodynamic investigation and environment impact assessment of hydrogen production from steam reforming of poultry tallow

    International Nuclear Information System (INIS)

    Highlights: • Thermodynamic analysis and environmental impact assessment of H2 production system. • Thermodynamic analysis identifies optimal conditions for H2 production. • LCA is applied to evaluate the environmental impacts of H2 production system. • Inventories data are derived from process simulation and from literature review. • Thermal energy process is the main contributor to the environmental impact. - Abstract: In this research, various assessment tools are applied to comprehensively investigate hydrogen production from steam reforming of poultry tallow (PT). These tools investigate the chemical reactions, design and simulate the entire hydrogen production process, study the energetic performance and perform an environment impact assessment using life cycle assessment (LCA) methodology. The chemical reaction investigation identifies thermodynamically optimal operating conditions at which PT may be converted to hydrogen via the steam reforming process. The synthesis gas composition was determined by simulations to minimize the Gibbs free energy using the Aspen Plus™ 10.2 software. These optimal conditions are, subsequently, used in the design and simulation of the entire PT-to-hydrogen process. LCA is applied to evaluate the environmental impacts of PT-to-hydrogen system. The system boundaries include rendering and reforming along with the required transportation process. The reforming inventories data are derived from process simulation in Aspen Plus™, whereas the rendering data are adapted from a literature review. The life cycle inventories data of PT-to-hydrogen are computationally implemented into SimaPro 7.3. A set of seven relevant environmental impact categories are evaluated: global warming, abiotic depletion, acidification, eutrophication, ozone layer depletion, photochemical oxidant formation, and cumulative non-renewable fossil and nuclear energy demand. The results are subject to a systematic sensitivity analysis and compared to

  2. Bio-ethanol steam reforming and autothermal reforming in 3- m channels coated with RhPd/CeO2 for hydrogen generation

    OpenAIRE

    Divins, N.J.; López, Eduardo; Rodríguez Martínez, Ángel; Vega, Didac; Llorca Piqué, Jordi

    2013-01-01

    A silicon micromonolith of 7 mm diameter and 0.2 mm length containing 1.5 million regular channels with a diameter of 3.3 μm was used for obtaining hydrogen through ethanol or bio-ethanol steam reforming (ESR) and oxidative steam reforming (OSR). The microchannels were coated with RhPd/CeO2 catalyst by a two-step method. First a CeO2 layer of ca. 100 nm thickness was deposited from cerium methoxyethoxide over a SiO2 layer, which was previously grown over the silicon microchannels by oxidation...

  3. Steam reforming as an alternative technique for treatment of oil sludge containing naturally occurring radioactive material

    International Nuclear Information System (INIS)

    Steam reforming treatment system is an innovative technology that holds a potential to treat mixed waste containing radioactive material. The system is utilizing the thermal heat of the superheated steam at 500 degree C to produce combustible gases and integrates it with ash melting at 1400 degree C for final destruction. In this system, liquids are evaporated, organics are converted into a hydrogen-rich gas, chlorinated compounds are converted in hydrochloric acid, and reactive chemicals in the waste containing radionuclide and heavy metals are converted into the stable product through ash melting dioxins and furans are not formed, but instead are destroyed in the reducing environment of the system. No secondary pollutants are produced from the system that requires subsequent treatment. The system is divided into three development stages, and currently the project is progressing at development stage 1. This project is an entailment of a concentrated effort to solve oil sludge containing radioactive material treatment issue. (Author)

  4. Steam reforming of methane over Pt/Rh based wire mesh catalyst in single channel reformer for small scale syngas production

    DEFF Research Database (Denmark)

    Sigurdsson, Haftor Örn; Kær, Søren Knudsen

    2012-01-01

    The purpose of this study is to investigate a small scale steam methane reformer for syngas production for a micro combined heat and power (mCPH) unit under different operational conditions. The study presents an experimental analysis of the performance of a specially built single channel of a...... evaluate the effect of flow maldistribution in a CPHE reformer stack on the CH4 conversion and H2 yield....

  5. Steam reforming of ethanol over Ni-based catalysts: Effect of feed composition on catalyst stability

    DEFF Research Database (Denmark)

    Trane-Restrup, Rasmus; Dahl, Søren; Jensen, Anker Degn

    2014-01-01

    In this work the effects of steam-to-carbon ratio (S/C), and addition of H2 or O2 to the feed on the product yields and carbon deposition in the steam reforming (SR) of ethanol over Ni/MgAl2O4, Ni/Ce0.6Zr0.4O2, and Ni/CeO2 at 600 °C have been investigated. Increasing the S/C-ratio from 1.6 to 8.3....../MgAl2O4 showed stable behavior and an average rate of carbon deposition of less than 7 μg C/gCat h. The results indicate that stable operation of ethanol SR is only possible under oxidative conditions.......In this work the effects of steam-to-carbon ratio (S/C), and addition of H2 or O2 to the feed on the product yields and carbon deposition in the steam reforming (SR) of ethanol over Ni/MgAl2O4, Ni/Ce0.6Zr0.4O2, and Ni/CeO2 at 600 °C have been investigated. Increasing the S/C-ratio from 1.6 to 8.......3 over Ni/MgAl2O4 increased conversion of ethanol as well as the yield of H2, while the carbon deposition and yield of hydrocarbons decreased. Oxygen addition at S/C-ratio of 6 over Ni/MgAl2O4, Ni/Ce0.6Zr0.4O2, and Ni/CeO2 increased conversion, decreased the yield of hydrocarbons, and led to a decrease...

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

    DEFF Research Database (Denmark)

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

    2014-01-01

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

  7. Catalytic Steam Reforming of Bio-Oil to Hydrogen Rich Gas

    OpenAIRE

    Trane-Restrup, Rasmus; Jensen, Anker Degn; Dahl, Søren

    2013-01-01

    Bio-oil is a liquid produced by pyrolysis of biomass and its main advantage compared with biomass is an up to ten times higher energy density. This entails lower transportation costs associated with the utilization of biomass for production of energy and fuels. Nevertheless, the bio-oil has a low heating value and high content of oxygen, which makes it unsuited for direct utilization in engines. One prospective technology for upgrading of bio-oil is steam reforming(SR), which can be used to p...

  8. Investigation of Fuel Chemistry and Bed Performance in a Fluidized Bed Black Liquor Steam Reformer

    Energy Technology Data Exchange (ETDEWEB)

    Kevin Whitty

    2007-06-30

    University of Utah's project entitled 'Investigation of Fuel Chemistry and Bed Performance in a Fluidized Bed Black Liquor Steam Reformer' (DOE Cooperative Agreement DE-FC26-02NT41490) was developed in response to a solicitation released by the U.S. Department of Energy in December 2001, requesting proposals for projects targeted towards black liquor/biomass gasification technology support research and development. Specifically, the solicitation was seeking projects that would provide technical support for Department of Energy supported black liquor and biomass gasification demonstration projects under development at the time.

  9. Methanol steam reforming over Cu/CeO2 catalysts: influence of zinc addition

    OpenAIRE

    Franco Tonelli; Osvaldo Gorriz; Luis Arrúa; Maria Cristina Abello

    2011-01-01

    Methanol steam reforming reaction was studied over Cu(5 wt.%)/CeO2 with and without the presence of Zn. The Zn addition decreased the Cu+2 reducibility and increased the oxygen mobility of ceria. The main products were CO2 and H2 with small amount of CO. Selectivity to CO decreased with the Zn addition and it was lower at lower reaction temperatures and lower space velocities. At 230 ºC and W/F MeOH = 648 g min mol-1 selectivities to H2 and to CO2 were 100% on Zn/Cu/Ce. The catalytic results ...

  10. Catalytic Study of Copper based Catalysts for Steam Reforming of Methanol

    OpenAIRE

    Purnama, H.

    2003-01-01

    The aim of this work is to study the catalytic properties of copper based catalysts used in the steam reforming of methanol. This method is known as one of the most favourable catalytic processes for producing hydrogen on-board. The catalysts investigated in this work are CuO/ZrO2 catalysts, which were prepared using different kinds of preparation methods and a commercial CuO/ZnO/Al2O3 catalyst which was used as a reference. The results of the studies can be divided into three sections: (i) T...

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

    OpenAIRE

    Mogensen, D.; J.-D. Grunwaldt; Hendriksen, P. V.; J. U. Nielsen; K. Dam-Johansen

    2014-01-01

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

  12. MATHEMATICAL MODELLING OF METHANE STEAM REFORMING IN A MEMBRANE REACTOR: AN ISOTHERMIC MODEL

    Directory of Open Access Journals (Sweden)

    E.M. ASSAF

    1998-06-01

    Full Text Available A mathematical modelling of one-dimensional, stationary and isothermic membrane reactor for methane steam reforming was developed to compare the maximum yield for methane conversion in this reactor with that in a conventional fixed-bed reactor. Fick's first law was used to describe the mechanism of hydrogen permeation. The variables studied include: reaction temperature, hydrogen feed flow rate and membrane thickness. The results show that the membrane reactor presents a higher methane conversion yield than the conventional fixed-bed reactor.

  13. Comparative thermoeconomic analysis of hydrogen production by water electrolysis and by ethanol steam reforming

    Energy Technology Data Exchange (ETDEWEB)

    Riveros-Godoy, Gustavo; Chavez-Rodriguez, Mauro; Cavaliero, Carla [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Mechanical Engineering School], Email: garg@fem.unicamp.br

    2010-07-01

    Hydrogen is the focus of this work that evaluates in comparative form through thermo economic analysis two hydrogen production processes: water electrolysis and ethanol steam reforming. Even though technical-economical barriers still exist for the development of an economy based on hydrogen, these difficulties are opportunities for the appearance of new business of goods and services, diversification of the energy mix, focus of research activities, development and support to provide sustainability to the new economy. Exergy and rational efficiency concept are used to make a comparison between both processes. (author)

  14. Stability of bimetallic Pd-Zn catalysts for the steam reforming of methanol

    OpenAIRE

    Conant, T.; Karim, A.; Lebarbier, V.; Wang, Y.; F. Girgsdies; Schlögl, R.; Datye, A.

    2008-01-01

    ZnO-supported palladium-based catalysts have been shown in recent years to be both active and selective towards the steam reforming of methanol, although they are still considered to be less active than traditional copper-based catalysts. The activity of PdZn catalysts can be significantly improved by supporting them on alumina. Here we show that the Pd/ZnO/Al2O3 catalysts have better long-term stability when compared with commercial Cu/ZnO/Al2O3 catalysts, and that they are also stable under...

  15. Hydrogen/syngas generation by simultaneous steam reforming and carbon dioxide absorption

    Energy Technology Data Exchange (ETDEWEB)

    Weimer, T.; Specht, M.; Baumgart, F.; Marquard-Moellenstedt, T.; Sichler, P. [IVE Weimer Process and Energy Technology, Sindelfingen (Germany)

    2002-07-01

    A new process for hydrogen or syngas production from various carbonaceous feedstocks is presented. The main feature of the Absorption Enhanced Reforming (AER-process) is the combination of simultaneous steam reforming, shift reaction and carbon dioxide removal in one reactor. Characterised by high efficiency, low investment cost and a high hydrogen content in the product gas, AER-processes are a promising option for hydrogen generation. Calcinated lime is a suitable carbon dioxide absorbent. In addition to hydrogen supply for electricity generation using PEM-fuel cells, industrial applications are in the refinery sector with a growing hydrogen demand for hydrotreating crude oil and the pulp industry where a lime recycle loop and power generation unit are already installed. 6 refs., 6 figs.

  16. Basic characteristics of heat-exchanger type steam reformer heated by high temperature helium gas, (2)

    International Nuclear Information System (INIS)

    A computer simulation model has been developed to analyze the basic characteristics of heat-exchanger type steam-methane reformer which is the key component to produce hydrogen using the nuclear process heat from high temperature gas cooled reactor. This model is based on the one-dimensional one taking account of heat transfer and reaction kinetics. In the previous report, the analytical model and the solution procedure have been described, and an example of calculation result has been shown compared with the experimental data in reference. This report describes simulation results of the dependencies of the characteristic quantities such as heat flux, reaction rates and hydrogen production rate in reformer tube on selected parameters, namely, the operating conditions (inlet gas temperatures, pressure and flow rates), the activities of the catalyst, the heat transfer rate and the dimensions of reaction tube. (author)

  17. Fabrication and characteristics of cube-post microreactors for methanol steam reforming

    International Nuclear Information System (INIS)

    Highlights: ► We developed a cube-post microreactor for methanol steam reforming. ► We investigated the influences of micro-milling parameters on the burr formation during fabricating the cube posts. ► Larger cutting speed, smaller feed rate and cutting depth are in favor of obtaining relatively small burrs. ► Cube post and manifold structure show important effects on reaction performances at relatively low reaction temperature. -- Abstract: The lamination-plate structure patterned with microchannels and triangle manifolds regarded as one of the preferred constructions for micro fuel reformers. Learned from the microchannel plate structure, a similar plate structure with cube-post array and triangle manifolds is proposed in this work. A micro-milling process is applied to fabricate the cube posts on the plate surface, and the influences of cutting parameters on the burr formation are analyzed. Experimental results indicate that larger cutting speed, smaller feed rate and cutting depth are in favor of obtaining relatively small burrs. Two plates with different cube-post dimensions and manifold structures are experimentally investigated the performances of methanol steam reforming over the Cu/Zn/Al/Zr catalyst. It indicates that the reactor with small-scale cube posts and acute triangle manifold presents better reforming performances at 260 °C than that of the one with large-scale cube posts and right triangle manifolds. However, their performances are closed to each other at relatively high reaction temperature since the catalyst activity is situated in dominated position at the time.

  18. STEAM AND SOFC BASED REFORMING OPTIONS OF PEM FUEL CELLS FOR MARINE APPLICATIONS

    Directory of Open Access Journals (Sweden)

    Mohamed M. El Gohary

    2015-06-01

    Full Text Available The need for green energy sources without or with low emissions in addition to improve the using efficiency of current fossil fuels in the marine field makes it important to replace or improve current fossil-fuelled engines. The replacement process should work on narrowing the gap between the most scientific innovative clean energy technologies and the concepts of feasibility and cost-effective solutions. Early expectations of very low emissions and relatively high efficiencies have been met in marine power plants using fuel cell. In this study, steam and SOFC based reforming options of natural gas for PEM fuel cells are proposed as an attractive option to limit the environmental impact of the marine sector. The benefits of these two different reforming options can be assessed using computer predictions incorporating chemical flow sheeting software. It is found that a high overall efficiency approaching 60% may be achieved using SOFC based reforming systems which are significantly better than a reformed PEM system or an SOFC only system.

  19. Bench-scale treatability studies for simulated incinerator scrubber blowdown containing radioactive cesium and strontium

    International Nuclear Information System (INIS)

    The purpose of this report is to document the results of bench-scale testing completed to remove 137Cs and 90Sr from the Oak Ridge K-25 Site Toxic Substances Control Act (TSCA) Incinerator blowdown at the K-25 Site Central Neutralization Facility, a wastewater treatment facility designed to remove heavy metals and uranium from various wastewaters. The report presents results of bench-scale testing using chabazite and clinoptilolite zeolites to remove cesium and strontium; using potassium cobalt ferrocyanide (KCCF) to remove cesium; and using strontium chloride coprecipitation, sodium phosphate coprecipitation, and calcium sulfate coprecipitation to remove strontium. Low-range, average-range, and high-range concentration blowdown surrogates were used to complete the bench-scale testing

  20. Semiconductor Photocatalysts for Non-oxidative Coupling, Dry Reforming and Steam Reforming of Methane

    OpenAIRE

    Shimura, Katsuya; Yoshida, Hisao

    2014-01-01

    Methane is one of the promising alternatives of petroleum, which should be used for not only a fuel but also a resource for hydrogen and more useful chemicals as with the petroleum. However, the selective methane conversion to them is still difficult in contrast to the combustion. Three types of photocatalytic reactions for methane conversion, i.e., the photocatalytic non-oxidative coupling of methane (2CH[4] → C[2]H[6] + H[2]), the photocatalytic dry reforming of methane (CH[4] + CO[2] → 2CO...

  1. Modelagem de um reator integral aplicado na reação de reforma a vapor de metano = Modeling of integral reactor applied methane steam reforming

    Directory of Open Access Journals (Sweden)

    Giane Gonçalves

    2007-07-01

    Full Text Available Freqüentemente, a validação de modelos matemáticos aplicados a reatores industriais esbarra na dificuldade de obtenção de medidas experimentais confiáveis. Uma maneira de contornar esta limitação corresponde à implantação de uma unidade em escala de bancada devidamente instrumentada, na qual são obtidos dados experimentais emcondições controladas. Neste contexto, foram efetuados ensaios em um reator integral de reforma a vapor de metano em escala de bancada, em diversas condições experimentais. As medidas de temperatura no leito foram efetuadas por meio de um termopar multiponto em seis posições axiais distintas, enquanto a composição do efluente do reator foi determinada por cromatografia gasosa. Estes dados experimentais foram comparados com as previsões de um modelo pseudo-homogêneo, unidimensional e dinâmico. Os resultados indicam que o modelo é adequado, sendo que tanto a atividade catalítica como a conversão são sensíveis à temperatura operacional, enquanto a temperatura do leito é praticamente insensível à vazão nas condições experimentais exploradas.Frequently, the validation of applied mathematical models of industrial reactors dash into the difficulty of obtaining reliable experimental data. A way to overcome this limitation is the proper use and operation or a in bench scale, experimental setup from whichexperimental data can be obtained in controlled conditions. In this context, experiments were carried out in an integral reactor of steam reform, in different experimental conditions. Thermocouples were placed along the catalyst bed to allow for temperature monitoring in six equally spaced and distinct positions of the reactor, the composition of the effluent of the reactor was determined by gas chromatography. These experimental data were compared with the theoretical results of a pseudo-homogeneous one-dimensional,dynamic mathematical model. The results indicate that the model can successfully

  2. Simulation Studies of the Hydrogen Production from Methanol Partial Oxidation Steam Reforming by a Tubular Packed-bed Catalytic Reactor

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Hydrogen production by partial oxidation steam reforming of methanol over a Cu/ZnO/Al2 O3 cata lyst has been paid more and more attention. The chemical equilibria involved in the methanol partial oxidation steam reforming reaction network such as methanol partial oxidation, methanol steam reforming, decomposition of methanol and water-gas shift reaction have been examined over the ranges of temperature 473-1073 K under normal pressure. Based on the detailed kinetics of these reactions over a Cu/ZnO/Al2O3 catalyst, and from the basic concept of the effectiveness factor, the intraparticle diffusion limitations were taken into account. The effec tiveness factors for each reaction along the bed length were calculated. Then important results were offered for the simulation of this reaction process.

  3. Low-temperature steam-reforming of ethanol over ZnO-supported Ni and Cu catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Homs, Narcis; Llorca, Jordi; De la Piscina, Pilar Ramirez [Departament de Quimica Inorganica, Universitat de Barcelona, C/Marti i Franques 1-11, 08028 Barcelona (Spain)

    2006-08-15

    ZnO-supported Ni and Cu as well as bimetallic Co-Ni and Co-Cu catalysts containing ca. 0.7wt% sodium promoter and prepared by the co-precipitation method were tested in the ethanol steam-reforming reaction at low temperature (523-723K), using a bioethanol-like mixture diluted in Ar. Monometallic ZnO-supported Cu or Ni samples do not exhibit good catalytic performance in the steam-reforming of ethanol for hydrogen production. Copper catalyst mainly dehydrogenates ethanol to acetaldehyde, whereas nickel catalyst favours ethanol decomposition. However, the addition of Ni to ZnO-supported cobalt has a positive effect both on the production of hydrogen at low temperature (<573K), and on catalyst stability. Evidence for alloy formation as well as mixed oxides at the microstructural level was found in the bimetallic systems after running the ethanol steam-reforming reaction by HRTEM-EELS. (author)

  4. Revised validation of thermal-hydraulic model of SCWO bench scale reactor

    International Nuclear Information System (INIS)

    The FLUENT computer code was used to construct a coupled fluid flow-chemical kinetics model of a MODAR bench scale reactor. This model predicted temperatures measured during MODAR test run 523.F very satisfactorily but required some modification to the measured boundary conditions. Several improvements to the model were made during a similar study of a MODAR pilot scale reactor. This report presents a rerun of the bench scale results using the updated model and shows better predictions than the initial runs. As before, the results of these calculations indicate that for better model validation, we need to obtain more accurate boundary conditions in future test runs

  5. Cometabolic biotreatment of TCE-contaminated groundwater: Laboratory and bench-scale development studies

    International Nuclear Information System (INIS)

    The Oak Ridge National Laboratory is conducting a demonstration of two cometabolic technologies for biotreatment of groundwater contaminated with trichloroethylene (TCE) and other organics. Technologies based on methanotrophic (methane-utilizing) and toluene-degrading microorganisms will be compared side-by-side on the same groundwater stream. Laboratory and bench-scale bioreactor studies have been conducted to guide selection of microbial cultures and operating conditions for the field demonstration. This report presents the results of the laboratory and bench-scale studies for the methanotrophic system

  6. Cometabolic biotreatment of TCE-contaminated groundwater - Laboratory and bench-scale development studies

    International Nuclear Information System (INIS)

    The Oak Ridge National Laboratory is conducting a demonstration of two cometabolic technologies for biotreatment of groundwater contaminated with trichloroethylene (TCE) and other organics. Technologies based on methanotrophic (methane-utilizing) and toluene-degrading microorganisms will be compared side-by-side on the same groundwater stream. Laboratory and bench-scale bioreactor studies have been conducted to guide selection of microbial cultures and operating conditions for the field demonstration. This report presents the results of the laboratory and bench-scale studies for the methanotrophic system. (author)

  7. Phase 2 THOR Steam Reforming Tests for Sodium Bearing Waste Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Nicholas R. Soelberg

    2004-01-01

    About one million gallons of acidic, hazardous, and radioactive sodium-bearing waste is stored in stainless steel tanks at the Idaho Nuclear Technology and Engineering Center (INTEC), which is a major operating facility of the Idaho National Engineering and Environmental Laboratory. Steam reforming is a candidate technology being investigated for converting the waste into a road ready waste form that can be shipped to the Waste Isolation Pilot Plant in New Mexico for interment. A steam reforming technology patented by Studsvik, Inc., and licensed to THOR Treatment Technologies has been tested in two phases using a Department of Energy-owned fluidized bed test system located at the Science Applications International Corporation (SAIC) Science and Technology Applications Research Center located in Idaho Falls, Idaho. The Phase 1 tests were reported earlier in 2003. The Phase 2 tests are reported here. For Phase 2, the process feed rate, stoichiometry, and chemistry were varied to identify and demonstrate process operation and product characteristics under different operating conditions. Two test series were performed. During the first series, the process chemistry was designed to produce a sodium carbonate product. The second series was designed to produce a more leach-resistant, mineralized sodium aluminosilicate product. The tests also demonstrated the performance of a MACT-compliant off-gas system.

  8. Phase 2 TWR Steam Reforming Test for Sodium-Bearing Waste Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Nicholas R. Soelberg; Doug Marshall; Dean Taylor; Steven Bates

    2004-01-01

    About one million gallons of acidic, hazardous, and radioactive sodium-bearing waste (SBW) is stored in stainless steel tanks a the Idaho Nuclear Technology and Engineering Center (INTEC), which is a major operating facility of the Idaho National Engineering and Environmental Laboratory (INEEL). Steam reforming is a candidate technology being investigated for converting the SBW into a road ready waste form that can be shipped to the Waste Isolation Pilot Plant in New Mexico for interment. Fluidized bed steam reforming technology, licensed to ThermoChem Waste Remediation, LLC (TWR) by Manufacturing Technology Conversion International, was tested in two phases using an INEEL (Department of Energy) fluidized bed test system located at the Science Applications International Corporation (SAIC) Science and Technology Applications Research Center in Idaho Falls, Idaho. The Phase 1 tests were reported earlier. The Phase 2 tests are reported here. For Phase 2, the process feed rate, reductant stoichiometry, and process temperature were varied to identify and demonstrate how the process might be optimized to improve operation and product characteristics. The first week of testing was devoted primarily to process chemistry and the second week was devoted more toward bed stability and particle size control.

  9. Phase 2 THOR Steam Reforming Tests for Sodium Bearing Waste Treatment

    International Nuclear Information System (INIS)

    About one million gallons of acidic, hazardous, and radioactive sodium-bearing waste is stored in stainless steel tanks at the Idaho Nuclear Technology and Engineering Center (INTEC), which is a major operating facility of the Idaho National Engineering and Environmental Laboratory. Steam reforming is a candidate technology being investigated for converting the waste into a road ready waste form that can be shipped to the Waste Isolation Pilot Plant in New Mexico for interment. A steam reforming technology patented by Studsvik, Inc., and licensed to THOR Treatment Technologies has been tested in two phases using a Department of Energy-owned fluidized bed test system located at the Science Applications International Corporation (SAIC) Science and Technology Applications Research Center located in Idaho Falls, Idaho. The Phase 1 tests were reported earlier in 2003. The Phase 2 tests are reported here. For Phase 2, the process feed rate, stoichiometry, and chemistry were varied to identify and demonstrate process operation and product characteristics under different operating conditions. Two test series were performed. During the first series, the process chemistry was designed to produce a sodium carbonate product. The second series was designed to produce a more leach-resistant, mineralized sodium aluminosilicate product. The tests also demonstrated the performance of a MACT-compliant off-gas system

  10. Dimethyl ether (DME) steam reforming process for hydrogen production by utilization of low temperature nuclear reactor

    International Nuclear Information System (INIS)

    he assessment of DME steam reforming process for hydrogen production by utilizing of low temperature nuclear reactor has been carried out. Difference with natural gas steam reforming that operates at high temperature (800-1000°C), the process operates at low temperature (300°C). This condition give the advantage since this process is not require high temperature materials for the plant, that economically more expensive. From the point of nuclear reactor application, all temperature range of nuclear reactors can be applied to supplied their heat for the process, include of commercially nuclear reactor in operation now. While, DME as raw material is free from sulfur content, so the operation unit of plant can be more compact, because the plant is not require the unit of desulfurization. The couple of the process with nuclear reactor is operate in cogeneration mode to produce electricity and hydrogen. The couple of low temperature nuclear reactor (LWR) with the process, with the configuration of upstream from turbine shows the potential of increasing efficiency from about 33% to 53% (30% efficiency of hydrogen production, and 23% electricity). While couple of the process with medium temperature nuclear reactor of FBR shows the potential of increasing efficiency from about 33% to 75% (49% efficiency of hydrogen production, and 26% electricity). (author)

  11. Exergoenvironmental analysis of a steam methane reforming process for hydrogen production

    International Nuclear Information System (INIS)

    Steam methane reforming (SMR) is one of the most promising processes for hydrogen production. Several studies have demonstrated its advantages from the economic viewpoint. Nowadays process development is based on technical and economical aspects; however, in the near future, the environmental impact will play a significant role in the design of such processes. In this paper, an SMR process is studied from the viewpoint of overall environmental impact, using an exergoenvironmental analysis. This analysis presents the combination of exergy analysis and life cycle assessment. Components where chemical reactions occur are the most important plant components from the exergoenvironmental point of view, because, in general, there is a high environmental impact associated with these components. This is mainly caused by the exergy destruction within the components, and this in turn is mainly due to the chemical reactions. The obtained results show that the largest potential for reducing the overall environmental impact is associated with the combustion reactor, the steam reformer, the hydrogen separation unit and the major heat exchangers. The environmental impact in these components can mainly be reduced by improving their exergetic efficiency. A sensitivity analysis for some important exergoenvironmental variables is also presented in the paper.

  12. Thermodynamic analysis of steam methane reforming reaction applied in Tokamak exhaust processing

    International Nuclear Information System (INIS)

    In Tokamak exhaust processing system, steam methane reforming reaction is expected to convert deuterium and tritium in the gaseous compounds to elementary gas, then the deuterium and tritium can be reclaimed. The method of Gibbs free energy minimization was employed to analyze the thermodynamic balance of steam methane reforming reaction. The effect of many factors, such as reaction temperature, reactants ratio, pressure, O2, CO2, H2 and CO, was investigated. The appropriate reaction condition is as follows: The temperature is between 650 ℃ and 700 ℃, the pressure is 1 × 105 Pa, and the ratio of water to methane is 1.5-2.0. Moreover, the presence of O2 or CO2 in reactants is favorable to lessen the yield of solid carbon and increase the conversion rate of hydrogen isotope. The presence of H2 does not affect the thermodynamic balance obviously, while CO increases solid carbon yield, which is a disadvantage to the reaction, so it needs to be wiped off before reaction. (authors)

  13. Influence of potassium on the competition between methane and ethane in steam reforming over Pt supported on yttrium-stabilized zirconia

    NARCIS (Netherlands)

    Graf, Patrick O.; Mojet, Barbara L.; Lefferts, Leon

    2008-01-01

    effect of addition of potassium to Pt supported on yttrium-stabilized zirconia (PtYSZ) catalyst for steam reforming of methane, ethane and methane/ethane mixtures was explored. Addition of potassium has a positive effect on preferential steam reforming of methane in mixtures of methane and ethane ov

  14. Methanol steam reforming in microreactor with constructal tree-shaped network

    Science.gov (United States)

    Chen, Yongping; Zhang, Chengbin; Wu, Rui; Shi, Mingheng

    2011-08-01

    The construcal tree-shaped network is introduced into the design of a methanol steam microreactor in the context of optimization of the flow configuration. A three-dimensional model for methanol steam reaction in this designed microreactor is developed and numerically analyzed. The methanol conversion, CO concentration in the product and the total pressure drop of the gases in the microreactor with constructal tree-shaped network are evaluated and compared with those in the serpentine reactor. It is found that the reaction of methanol steam reforming is enhanced in the constructal tree-shaped microreactor, since the tree-shaped reactor configuration, which acts an optimizer for the reactant distribution, provides a reaction space with larger surface-to-volume ratio and the reduction of reactant velocities in the branches. Compared with the serpentine microreactor, the constructal reactor possesses a higher methanol conversion rate accompanied with a higher CO concentration. The conversion rate of the constructal microreactor is more than 10% over that of serpentine reactor. More particularly, the reduction of flow distance makes the constructal microreactor still possess almost the same pressure drop as the corresponding serpentine reactor, despite that the bifurcations induce extra local pressure loss, and the reduction of channel size in branches also causes pressure losses.

  15. Engineering Study for a Full Scale Demonstration of Steam Reforming Black Liquor Gasification at Georgia-Pacific's Mill in Big Island, Virginia; FINAL

    International Nuclear Information System (INIS)

    Georgia-Pacific Corporation performed an engineering study to determine the feasibility of installing a full-scale demonstration project of steam reforming black liquor chemical recovery at Georgia-Pacific's mill in Big Island, Virginia. The technology considered was the Pulse Enhanced Steam Reforming technology that was developed and patented by Manufacturing and Technology Conversion, International (MTCI) and is currently licensed to StoneChem, Inc., for use in North America. Pilot studies of steam reforming have been carried out on a 25-ton per day reformer at Inland Container's Ontario, California mill and on a 50-ton per day unit at Weyerhaeuser's New Bern, North Carolina mill

  16. Hydrogen from biomass gas steam reforming for low temperature fuel cell: energy and exergy analysis

    Directory of Open Access Journals (Sweden)

    A. Sordi

    2009-03-01

    Full Text Available This work presents a method to analyze hydrogen production by biomass gasification, as well as electric power generation in small scale fuel cells. The proposed methodology is the thermodynamic modeling of a reaction system for the conversion of methane and carbon monoxide (steam reforming, as well as the energy balance of gaseous flow purification in PSA (Pressure Swing Adsorption is used with eight types of gasification gases in this study. The electric power is generated by electrochemical hydrogen conversion in fuel cell type PEMFC (Proton Exchange Membrane Fuel Cell. Energy and exergy analyses are applied to evaluate the performance of the system model. The simulation demonstrates that hydrogen production varies with the operation temperature of the reforming reactor and with the composition of the gas mixture. The maximum H2 mole fraction (0.6-0.64 mol.mol-1 and exergetic efficiency of 91- 92.5% for the reforming reactor are achieved when gas mixtures of higher quality such as: GGAS2, GGAS4 and GGAS5 are used. The use of those gas mixtures for electric power generation results in lower irreversibility and higher exergetic efficiency of 30-30.5%.

  17. Effects of key factors on solar aided methane steam reforming in porous medium thermochemical reactor

    International Nuclear Information System (INIS)

    Highlights: • Effects of key factors on chemical reaction for solar methane reforming are studied. • MCRT and FVM method coupled with UDFs is used to establish numerical model. • Heat and mass transfer model coupled with thermochemical reaction is established. • LTNE model coupled with P1 approximation is used for porous matrix solar reactor. • A formula between H2 production and conductivity of porous matrix is put forward. - Abstract: With the aid of solar energy, methane reforming process can save up to 20% of the total methane consumption. Monte Carlo Ray Tracing (MCRT) method and Finite Volume Method (FVM) combined method are developed to establish the heat and mass transfer model coupled with thermochemical reaction kinetics for porous medium solar thermochemical reactor. In order to provide more temperature information, local thermal non-equilibrium (LTNE) model coupled with P1 approximation is established to investigate the thermal performance of porous medium solar thermochemical reaction. Effects of radiative heat loss and thermal conductivity of porous matrix on temperature distribution and thermochemical reaction for solar driven steam methane reforming process are numerically studied. Besides, the relationship between hydrogen production and thermal conductivity of porous matrix are analyzed. The results illustrate that hydrogen production shows a 3 order polynomial relation with thermal conductivity of porous matrix

  18. Investigation of methane steam reforming in planar porous support of solid oxide fuel cell

    International Nuclear Information System (INIS)

    Adopting the porous support in integrated-planar solid oxide fuel cell (IP-SOFC) can reduce the operating temperature by reducing thickness of electrolyte layer, and also, provide internal reforming environment for hydrogen-rich fuel gas. The distributions of reactant and product components, and temperature of methane steam reforming for IP-SOFC were investigated by the developed physical and mathematical model with thermodynamic analysis, in which eleven possible reaction mechanisms were considered by the source terms and Arrhenius relationship. Numerical simulation of the model revealed that the progress of reforming reaction and the distribution of the product, H2, were influenced by the operating conditions, included that of temperature, ratio of H2O and CH4, as well as by the porosity of the supporting material. The simulating results indicate that the methane conversion rate can reach its maximum value under the operating temperature of 800 deg. C and porosity of ε = 0.4, which rather approximate to the practical operating conditions of IP-SOFC. In addition, characteristics of carbon deposition on surface of catalyst were discussed under various operating conditions and configuration parameters of the porous support. The present works provided some theoretical explanations to the numerous experimental observations and engineered practices

  19. Ni-Based Catalysts for Low Temperature Methane Steam Reforming: Recent Results on Ni-Au and Comparison with Other Bi-Metallic Systems

    OpenAIRE

    Anna M. Venezia; Fabrizio Puleo; Valeria La Parola; Giuseppe Pantaleo; Hongjing Wu; Leonarda F. Liotta

    2013-01-01

    Steam reforming of light hydrocarbons provides a promising method for hydrogen production. Ni-based catalysts are so far the best and the most commonly used catalysts for steam reforming because of their acceptably high activity and significantly lower cost in comparison with alternative precious metal-based catalysts. However, nickel catalysts are susceptible to deactivation from the deposition of carbon, even when operating at steam-to-carbon ratios predicted to be thermodynamically outside...

  20. Activity of Ni–Cu–Al based catalyst for renewable hydrogen production from steam reforming of glycerol

    International Nuclear Information System (INIS)

    Highlights: • Ni–Cu–Al catalyst for hydrogen production was synthesized by rising pH technique. • Experimental data were analyzed with non-stoichiometric thermodynamic calculation. • Catalyst deactivation due to carbon deposits in glycerol steam reforming was found. • Carbon removal was analyzed by TGA experiment during medium temperature oxidation. • Reforming was tested by separability kinetics of rate law and catalyst deactivation. - Abstract: In this study, the activity of Ni–Cu–Al based catalyst for renewable hydrogen production from glycerol steam reforming has been evaluated in a continuous flow fixed-bed reactor under atmospheric pressure at 500–600 °C. The catalyst synthesized by the co-precipitation method with rising pH technique was characterized by the elemental analysis, Brenauer–Emmett–Teller (N2-BET) adsorption method, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM) and thermogravimetric analysis (TGA). The thermodynamic analysis for glycerol steam reforming was conducted by using a non-stoichiometric methodology based on the minimization of Gibbs free energy. The obtained results revealed that the great quantity of hydrogen is produced at excess water and the formations of CH4 and CO in the glycerol steam reforming were almost negligible. The deactivation of catalyst due to the formation of carbon residues was observed. The carbons removal was measured by TGA experiment during medium temperature oxidation conditions. The kinetics on glycerol steam reforming was described by means of the separability concept of reaction rate law and deactivation model, and the kinetic parameters were calculated

  1. Energy efficiency of a direct-injection internal combustion engine with high-pressure methanol steam reforming

    International Nuclear Information System (INIS)

    This article discusses the concept of a direct-injection ICE (internal combustion engine) with thermo-chemical recuperation realized through SRM (steam reforming of methanol). It is shown that the energy required to compress the reformate gas prior to its injection into the cylinder is substantial and has to be accounted for. Results of the analysis prove that the method of reformate direct-injection is unviable when the reforming is carried-out under atmospheric pressure. To reduce the energy penalty resulted from the gas compression, it is suggested to implement a high-pressure reforming process. Effects of the injection timing and the injector's flow area on the ICE-SRM system's fuel conversion efficiency are studied. The significance of cooling the reforming products prior to their injection into the engine-cylinder is demonstrated. We show that a direct-injection ICE with high-pressure SRM is feasible and provides a potential for significant efficiency improvement. Development of injectors with greater flow area shall contribute to further efficiency improvements. - Highlights: • Energy needed to compress the reformate is substantial and has to be accounted for. • Reformate direct-injection is unviable if reforming is done at atmospheric pressure. • Direct-injection engine with high-pressure methanol reforming is feasible. • Efficiency improvement by 12–14% compared with a gasoline-fed engine was shown

  2. Bench-scale Kinetics Study of Mercury Reactions in FGD Liquors

    Energy Technology Data Exchange (ETDEWEB)

    Gary Blythe; John Currie; David DeBerry

    2008-03-31

    This document is the final report for Cooperative Agreement DE-FC26-04NT42314, 'Kinetics Study of Mercury Reactions in FGD Liquors'. The project was co-funded by the U.S. DOE National Energy Technology Laboratory and EPRI. The objective of the project has been to determine the mechanisms and kinetics of the aqueous reactions of mercury absorbed by wet flue gas desulfurization (FGD) systems, and develop a kinetics model to predict mercury reactions in wet FGD systems. The model may be used to determine optimum wet FGD design and operating conditions to maximize mercury capture in wet FGD systems. Initially, a series of bench-top, liquid-phase reactor tests were conducted and mercury species concentrations were measured by UV/visible light spectroscopy to determine reactant and byproduct concentrations over time. Other measurement methods, such as atomic absorption, were used to measure concentrations of vapor-phase elemental mercury, that cannot be measured by UV/visible light spectroscopy. Next, a series of bench-scale wet FGD simulation tests were conducted. Because of the significant effects of sulfite concentration on mercury re-emission rates, new methods were developed for operating and controlling the bench-scale FGD experiments. Approximately 140 bench-scale wet FGD tests were conducted and several unusual and pertinent effects of process chemistry on mercury re-emissions were identified and characterized. These data have been used to develop an empirically adjusted, theoretically based kinetics model to predict mercury species reactions in wet FGD systems. The model has been verified in tests conducted with the bench-scale wet FGD system, where both gas-phase and liquid-phase mercury concentrations were measured to determine if the model accurately predicts the tendency for mercury re-emissions. This report presents and discusses results from the initial laboratory kinetics measurements, the bench-scale wet FGD tests, and the kinetics modeling

  3. Steam Reforming of Ethylene Glycol over MgAl₂O₄ Supported Rh, Ni, and Co Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Mei, Donghai; Lebarbier, Vanessa M.; Xing, Rong; Albrecht, Karl O.; Dagle, Robert A.

    2015-11-25

    Steam reforming of ethylene glycol (EG) over MgAl₂O₄ supported metal (15 wt.% Ni, 5 wt.% Rh, and 15 wt.% Co) catalysts were investigated using combined experimental and theoretical methods. Compared to highly active Rh and Ni catalysts with 100% conversion, the steam reforming activity of EG over the Co catalyst is comparatively lower with only 42% conversion under the same reaction conditions (500°C, 1 atm, 119,000 h⁻¹, S/C=3.3 mol). However, CH₄ selectivity over the Co catalyst is remarkably lower. For example, by varying the gas hour space velocity (GHSV) such that complete conversion is achieved for all the catalysts, CH₄ selectivity for the Co catalyst is only 8%, which is much lower than the equilibrium CH₄ selectivity of ~ 24% obtained for both the Rh and Ni catalysts. Further studies show that varying H₂O concentration over the Co catalyst has a negligible effect on activity, thus indicating zero-order dependence on H₂O. These experimental results suggest that the supported Co catalyst is a promising EG steam reforming catalyst for high hydrogen production. To gain mechanistic insight for rationalizing the lower CH₃ selectivity observed for the Co catalyst, the initial decomposition reaction steps of ethylene glycol via C-O, O-H, C-H, and C-C bond scissions on the Rh(111), Ni(111) and Co(0001) surfaces were investigated using density functional theory (DFT) calculations. Despite the fact that the bond scission sequence in the EG decomposition on the three metal surfaces varies, which leads to different reaction intermediates, the lower CH₄ selectivity over the Co catalyst, as compared to the Rh and Ni catalysts, is primarily due to the higher barrier for CH₄ formation. The higher S/C ratio enhances the Co catalyst stability, which can be elucidated by the facile water dissociation and an alternative reaction path to remove the CH species as a coking precursor via the HCOH formation. This work was financially supported by the United

  4. Fluidized Bed Steam Reforming of INEEL SBW Using THORsm Mineralizing Technology

    Energy Technology Data Exchange (ETDEWEB)

    Arlin L. Olson; Nicholas R. Soelberg; Douglas W. Marshall; Gary L. Anderson

    2004-12-01

    Sodium bearing waste (SBW) disposition is one of the U.S. Department of Energy (DOE) Idaho Operation Office’s (NE-ID) and State of Idaho’s top priorities at the Idaho National Engineering and Environmental Laboratory (INEEL). Many studies have resulted in the identification of five treatment alternatives that form a short list of perhaps the most appropriate technologies for the DOE to select from. The alternatives are (a) calcination with maximum achievable control technology (MACT) upgrade, (b) steam reforming, (c) cesium ion exchange (CsIX) with immobilization, (d) direct evaporation, and (e) vitrification. Each alternative has undergone some degree of applied technical development and preliminary process design over the past four years. DOE desired further experimental data, with regard to steam reforming technology, to make informed decisions concerning selection of treatment technology for SBW. Mineralizing steam reforming technology, offered by THOR Treatment Technologies, LLC would produce a denitrated, granular mineral waste form using a high-temperature fluidized bed process. A pilot scale demonstration of the technology was performed in a 15-cm-diameter reactor vessel September 27 through October 1, 2004. The pilot scale equipment is owned by the DOE, and located at the Science and Technology Applications Research (STAR) Center in Idaho Falls, ID. Flowsheet chemistry and operational parameters were defined through a collaborative effort involving Idaho National Engineering and Environmental Laboratory, Savannah River National Laboratory (SRNL), and THOR Treatment Technologies personnel. Personnel from Science Applications International Corporation, owners of the STAR Center, operated the pilot plant. The pilot scale test was terminated as planned after achieving a total of 100 hrs of cumulative/continuous processing operation. About 230 kg of SBW surrogate were processed that resulted in about 88 kg of solid product, a mass reduction of about 62

  5. An attempt to minimize the temperature gradient along a plug-flow methane/steam reforming reactor by adopting locally controlled heating zones

    Science.gov (United States)

    Mozdzierz, M.; Brus, G.; Sciazko, A.; Komatsu, Y.; Kimijima, S.; Szmyd, J. S.

    2014-08-01

    Plug flow reactors are very common in the chemical process industry, including methane/steam reforming applications. Their operation presents many challenges, such as a strong dependence of temperature and composition distribution on the inlet conditions. The strongly endothermic methane/steam reforming reaction might result in a temperature drop at the inlet of the reactor and consequently the occurrence of large temperature gradients. The strongly non-uniform temperature distribution due to endothermic chemical reaction can have tremendous consequences on the operation of the reactor, such as catalyst degradation, undesired side reactions and thermal stresses. To avoid such unfavorable conditions, thermal management of the reactor becomes an important issue. To carry out thermal management properly, detailed modeling and corresponding numerical analyses of the phenomena occurring inside the reforming system is required. This paper presents experimental and numerical studies on the methane/steam reforming process inside a plug-flow reactor. To optimize the reforming reactors, detailed data about the entire reforming process is required. In this study the kinetics of methane/steam reforming on the Ni/YSZ catalyst was experimentally investigated. Measurements including different thermal boundary conditions, the fuel flow rate and the steam- to-methane ratios were performed. The reforming rate equation derived from experimental data was used in the numerical model to predict gas composition and temperature distribution along the steam-reforming reactor. Finally, an attempt was made to control the temperature distribution by adopting locally controlled heating zones.

  6. An attempt to minimize the temperature gradient along a plug-flow methane/steam reforming reactor by adopting locally controlled heating zones

    International Nuclear Information System (INIS)

    Plug flow reactors are very common in the chemical process industry, including methane/steam reforming applications. Their operation presents many challenges, such as a strong dependence of temperature and composition distribution on the inlet conditions. The strongly endothermic methane/steam reforming reaction might result in a temperature drop at the inlet of the reactor and consequently the occurrence of large temperature gradients. The strongly non-uniform temperature distribution due to endothermic chemical reaction can have tremendous consequences on the operation of the reactor, such as catalyst degradation, undesired side reactions and thermal stresses. To avoid such unfavorable conditions, thermal management of the reactor becomes an important issue. To carry out thermal management properly, detailed modeling and corresponding numerical analyses of the phenomena occurring inside the reforming system is required. This paper presents experimental and numerical studies on the methane/steam reforming process inside a plug-flow reactor. To optimize the reforming reactors, detailed data about the entire reforming process is required. In this study the kinetics of methane/steam reforming on the Ni/YSZ catalyst was experimentally investigated. Measurements including different thermal boundary conditions, the fuel flow rate and the steam- to-methane ratios were performed. The reforming rate equation derived from experimental data was used in the numerical model to predict gas composition and temperature distribution along the steam-reforming reactor. Finally, an attempt was made to control the temperature distribution by adopting locally controlled heating zones.

  7. Fluidized bed steam reformed mineral waste form performance testing to support Hanford Supplemental Low Activity Waste Immobilization Technology Selection

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Pierce, E. M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bannochie, C. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Burket, P. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Cozzi, A. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Crawford, C. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Daniel, W. E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Herman, C. C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Miller, D. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Missimer, D. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nash, C. A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Williams, M. F. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Brown, C. F. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Qafoku, N. P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Neeway, J. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Valenta, M. M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gill, G. A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Swanberg, D. J. [Washington River Protection Solutions (WRPS), Richland, WA (United States); Robbins, R. A. [Washington River Protection Solutions (WRPS), Richland, WA (United States); Thompson, L. E. [Washington River Protection Solutions (WRPS), Richland, WA (United States)

    2015-10-01

    This report describes the benchscale testing with simulant and radioactive Hanford Tank Blends, mineral product characterization and testing, and monolith testing and characterization. These projects were funded by DOE EM-31 Technology Development & Deployment (TDD) Program Technical Task Plan WP-5.2.1-2010-001 and are entitled “Fluidized Bed Steam Reformer Low-Level Waste Form Qualification”, Inter-Entity Work Order (IEWO) M0SRV00054 with Washington River Protection Solutions (WRPS) entitled “Fluidized Bed Steam Reforming Treatability Studies Using Savannah River Site (SRS) Low Activity Waste and Hanford Low Activity Waste Tank Samples”, and IEWO M0SRV00080, “Fluidized Bed Steam Reforming Waste Form Qualification Testing Using SRS Low Activity Waste and Hanford Low Activity Waste Tank Samples”. This was a multi-organizational program that included Savannah River National Laboratory (SRNL), THOR® Treatment Technologies (TTT), Pacific Northwest National Laboratory (PNNL), Oak Ridge National Laboratory (ORNL), Office of River Protection (ORP), and Washington River Protection Solutions (WRPS). The SRNL testing of the non-radioactive pilot-scale Fluidized Bed Steam Reformer (FBSR) products made by TTT, subsequent SRNL monolith formulation and testing and studies of these products, and SRNL Waste Treatment Plant Secondary Waste (WTP-SW) radioactive campaign were funded by DOE Advanced Remediation Technologies (ART) Phase 2 Project in connection with a Work-For-Others (WFO) between SRNL and TTT.

  8. Methanol steam reforming over Cu/Ce O2 catalysts. Influence of zinc addition

    International Nuclear Information System (INIS)

    Methanol steam reforming reaction was studied over Cu(5 wt.%)/CeO2 with and without the presence of Zn. The Zn addition decreased the Cu+2 reducibility and increased the oxygen mobility of ceria. The main products were CO2 and H2 with small amount of CO. Selectivity to CO decreased with the Zn addition and it was lower at lower reaction temperatures and lower space velocities. At 230 degree C and W/FMeOH = 648 g min mol-1 selectivities to H2 and to CO2 were 100% on Zn/Cu/Ce. The catalytic results indicated that CO was mainly a secondary product formed from reverse water gas shift reaction. (author)

  9. Methanol steam reforming over Cu/CeO2 catalysts: influence of zinc addition

    Directory of Open Access Journals (Sweden)

    Franco Tonelli

    2011-01-01

    Full Text Available Methanol steam reforming reaction was studied over Cu(5 wt.%/CeO2 with and without the presence of Zn. The Zn addition decreased the Cu+2 reducibility and increased the oxygen mobility of ceria. The main products were CO2 and H2 with small amount of CO. Selectivity to CO decreased with the Zn addition and it was lower at lower reaction temperatures and lower space velocities. At 230 ºC and W/F MeOH = 648 g min mol-1 selectivities to H2 and to CO2 were 100% on Zn/Cu/Ce. The catalytic results indicated that CO was mainly a secondary product formed from reverse water gas shift reaction.

  10. Cu-Al spinel oxide as an efficient catalyst for methanol steam reforming.

    Science.gov (United States)

    Xi, Hongjuan; Hou, Xiaoning; Liu, Yajie; Qing, Shaojun; Gao, Zhixian

    2014-10-27

    Cu-Al spinel oxide, which contains a small portion of the CuO phase, has been successfully used in methanol steam reforming (MSR) without prereduction. The omission of prereduction not only avoids the copper sintering prior to the catalytic reaction, but also slows down the copper-sintering rate in MSR. During this process, the CuO phase can initiate MSR at a lower temperature, and CuAl2O4 releases active copper gradually. The catalyst CA2.5-900, calcined at 900 °C with n(Al)/n(Cu) = 2.5, has a higher CuAl2O4 content, higher BET surface area, and smaller CuAl2O4 crystal size. Its activity first increases and then decreases during MSR. Furthermore, both fresh and regenerated CA2.5-900 showed better catalytic performance than the commercial Cu-Zn-Al catalyst. PMID:25213737

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

    Directory of Open Access Journals (Sweden)

    D. Mogensen

    2014-01-01

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

  12. The influence of Ni loading on coke formation in steam reforming of acetic acid

    Energy Technology Data Exchange (ETDEWEB)

    An, Lu; Dong, Changqing; Yang, Yongping; Zhang, Junjiao; He, Lei [National Engineering Laboratory of Biomass Power Generation Equipment, North China Electric Power University, Beijing 102206 (China)

    2011-03-15

    Steam reforming of acetic acid on Ni/{gamma}-Al{sub 2}O{sub 3} with different nickel loading for hydrogen production was investigated in a tubular reactor at 600 C, 1 atm, H2O/HAc = 4, and WHSV = 5.01 g-acetic acid/g-cata.h{sup -1}. The catalysts were characterized by temperature programmed oxidation (TPO) and differential thermal analysis (DTA), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The results showed that the amount of deposited carbidic-like carbon decreased and graphitic-like carbon increased with Ni loading increasing from 9 to 15 wt%. The Ni/{gamma}-Al{sub 2}O{sub 3} catalyst with 12 wt% Ni loading had higher catalytic activity and lower coke deposited rate. (author)

  13. Radioactive Demonstrations Of Fluidized Bed Steam Reforming (FBSR) With Hanford Low Activity Wastes

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C. M.; Crawford, C. L.; Burket, P. R.; Bannochie, C. J.; Daniel, W. G.; Nash, C. A.; Cozzi, A. D.; Herman, C. C.

    2012-10-22

    Several supplemental technologies for treating and immobilizing Hanford low activity waste (LAW) are being evaluated. One immobilization technology being considered is Fluidized Bed Steam Reforming (FBSR) which offers a low temperature (700-750?C) continuous method by which wastes high in organics, nitrates, sulfates/sulfides, or other aqueous components may be processed into a crystalline ceramic (mineral) waste form. The granular waste form produced by co-processing the waste with kaolin clay has been shown to be as durable as LAW glass. The FBSR granular product will be monolithed into a final waste form. The granular component is composed of insoluble sodium aluminosilicate (NAS) feldspathoid minerals such as sodalite. Production of the FBSR mineral product has been demonstrated both at the industrial, engineering, pilot, and laboratory scales on simulants. Radioactive testing at SRNL commenced in late 2010 to demonstrate the technology on radioactive LAW streams which is the focus of this study.

  14. Steam Reforming of Dimethyl Ether by Gliding Arc Gas Discharge Plasma for Hydrogen Production

    Institute of Scientific and Technical Information of China (English)

    王保伟; 孙启梅; 吕一军; 杨美琳; 闫文娟

    2014-01-01

    Gliding arc gas discharge plasma was used for the generation of hydrogen from steam reforming of di-methyl ether (DME). A systemic procedure was employed to determine the suitable experimental conditions. It was found that DME conversion first increased up to the maximum and then decreased slightly with the increase of added water and air. The increase of total feed gas flow rate resulted in the decrease of DME conversion and hy-drogen yield, but hydrogen energy consumption dropped down to the lowest as total feed gas flow rate increased to 76 ml·min-1. Larger electrode gap and higher discharge voltage were advantageous. Electrode shape had an impor-tant effect on the conversion of DME and production of H2. Among the five electrodes, electrode 2# with valid length of 55 mm and the radian of 34 degrees of the top electrode section was the best option, which enhanced ob-viously the conversion of DME.

  15. The Activity of Ni-Based Catalysts on Steam Reforming of Glycerol for Hydrogen Production

    Directory of Open Access Journals (Sweden)

    ALI SALEM EBSHISH

    2011-09-01

    Full Text Available Glycerol, the readily available bio renewable material, is effectively utilized for hydrogen production by a steam reforming reaction. The experiments were carried out in a continuous flow fixed-bed reactor over Nickel supported alumina catalysts under atmospheric pressure at 600°C and three hours reaction time. 5%wt Ni was loaded over γ-Al2O3 and effect of promoter metals such as Fe and Co over Ni/γ-Al2O3 catalytic systems were evaluated. The catalysts were characterized by BET surface area, XRD and SEM techniques. The activity results showed that the addition of Co enhanced the catalyst performance. The catalysts exhibited a good activity and selectivity to hydrogen.

  16. Stable hydrogen production by methane steam reforming in a two zone fluidized bed reactor: Experimental assessment

    Science.gov (United States)

    Pérez-Moreno, L.; Soler, J.; Herguido, J.; Menéndez, M.

    2013-12-01

    The Two Zone Fluidized Bed Reactor concept is proposed for hydrogen production via the steam reforming of methane (SRM) including integrated catalyst regeneration. In order to study the effect of the contact mode, the oxidative SRM has been carried out over a Ni/Al2O3 catalyst using a fixed bed reactor (fBR), a conventional fluidized-bed reactor (FBR) and the proposed two-zone fluidized bed reactor (TZFBR). The technical feasibility of these reactors has been studied experimentally, investigating their performance (CH4 conversion, CO and H2 selectivity, and H2 global yield) and stability under different operating conditions. Coke generation in the process has been verified by several techniques. A stable performance was obtained in the TZFBR, where coke formation was counteracted with continuous catalyst regeneration. The viability of the TZFBR for carrying out this process with a valuable global yield to hydrogen is demonstrated.

  17. Out-of-pile demonstration test of HTTR hydrogen production system structure and fabrication technology of steam reformer. Contract research

    International Nuclear Information System (INIS)

    A hydrogen production system by steam reforming of natural gas, chemical reaction; CH4+H2O = 3H2+CO, is to be the first heat utilization system of the HTTR. Prior to coupling of the steam reforming system with the HTTR, an out-of-pile test facility is presently under construction in order to confirm safety, controllability and performance of the steam reforming system under simulated operational conditions of the HTTR hydrogen production system. The out-of-pile test facility, using an electric heater as a reactor substitute, simulates key components downstream an intermediate heat exchanger of the HTTR hydrogen production system on a scale of 1 to 30 with a hydrogen production rate of 110 Nm3/h. A steam reformer (SR) is a key component to produce hydrogen by steam reforming of natural gas. A bayonet-type catalyst tube was applied to the SR of the out-of-pile test facility in order to enhance the heat utilization rate. Also to promote heat transfer, the thickness of the catalyst tube should be decreased to 10 mm while augmenting heat transfer by fins formed on the outer surface of the catalyst tube. Therefore, the catalyst tube was designed on the basis of pressure difference between helium and process gases instead of total pressure of them. This design method was authorized for the first time in Japan. Furthermore, a function of explosion proof was applied to the SR because it contains inflammable gas and electric heater. This report describes the structure of the SR as well as the authorization both of the design method of the catalyst tube and the explosion proof function of the SR. (author)

  18. Hydrogen production through sorption-enhanced steam methane reforming and membrane technology: A review

    International Nuclear Information System (INIS)

    With the rapid development of industry, more and more waste gases are emitted into the atmosphere. In terms of total air emissions, CO2 is emitted in the greatest amount, accounting for 99 wt% of the total air emissions, therefore contributing to global warming, the so-called 'Greenhouse Effect'. The recovery and disposal of CO2 from flue gas is currently the object of great international interest. Most of the CO2 comes from the combustion of fossil fuels in power generation, industrial boilers, residential and commercial heating, and transportation sectors. Consequently, in the last years' interest in hydrogen as an energy carrier has significantly increased both for vehicle fuelling and stationary energy production from fuel cells. The benefits of a hydrogen energy policy are the reduction of the greenhouse effect, principally due to the centralization of the emission sources. Moreover, an improvement to the environmental benefits can be achieved if hydrogen is produced from renewable sources, as biomass. The present paper provides an overview of the steam methane reforming (SMR) process and methodologies for performances improvement such as hydrogen removal, by selective permeation through a membrane or simultaneous reaction of the targeted molecule with a chemical acceptor, and equilibrium shift by the addition of a CO2 acceptor to the reactor. In particular, attention was focused on the sorption-enhanced steam methane reforming (SE-SMR) process in which sorbents are added in order to enhance the reactions and realize in situ CO2 separation. The major operating parameters of SE-SMR are described by the authors in order to project and then realize the innovative carbonation reactor developed in previous studies

  19. Energy balance of a dielectric barrier discharge reactor for hydrocarbon steam reforming

    International Nuclear Information System (INIS)

    In the future, hydrogen is supposed to play an important role in the worldwide energy supply. It allows a more efficient utilization of fossil fuels and the reduction of noxious emissions, e. g. by fuel cells or the use of hydrogen enriched fuels in combustion engines or gas turbines. Plasma methods are expected to allow low temperature and fuel flexible on-site hydrogen generation. They are also favorable in terms of a dynamic behavior at load changes, which is particularly important in mobile applications. However, one has to ensure an efficient plasma generation. Experiments on methane steam reforming for hydrogen generation with a dielectric barrier discharge (DBD) reactor were performed. A strong temperature rise of the reactor was observed when the plasma was ignited. To investigate the source of this heating effect, the DBD reactor was furnished with a series of temperature sensors and a constant power electrical heating to determine and quantify the input and output heat fluxes of the reactor. It was possible to strike an energy balance over the reactor including both thermal heat fluxes and the reaction enthalpy. It appears that more than 60 % of the electrical energy input is spent for heating of the dielectric barrier. This effect is independent of the gas type or the presence of chemical conversion, since similar results are obtained when pure nitrogen is fed to the DBD reactor. Nevertheless, it has been demonstrated that steam reforming reactions can be induced by DBD at temperatures below 400 Celsius degrees, which is not possible with purely catalytic methods. (author)

  20. Improved catalytic performance of Ni catalysts for steam methane reforming in a micro-channel reactor

    Institute of Scientific and Technical Information of China (English)

    Bozhao Chu; Nian Zhang; Xuli Zhai; Xin Chen; Yi Cheng

    2014-01-01

    Milliseconds process to produce hydrogen by steam methane reforming (SMR) reaction, based on Ni catalyst rather than noble catalyst such as Pd, Rh or Ru, in micro-channel reactors has been paid more and more attentions in recent years. This work aimed to further improve the catalytic performance of nickel-based catalyst by the introduction of additives, i.e., MgO and FeO, prepared by impregnation method on the micro-channels made of metal-ceramic complex substrate. The prepared catalysts were tested in the same micro-channel reactor by switching the catalyst plates. The results showed that among the tested catalysts Ni-Mg catalyst had the highest activity, especially under harsh conditions, i.e., at high space velocity and/or low reaction temperature. Moreover, the catalyst activity and selectivity were stable during the 12 h on stream test even when the ratio of steam to carbon (S/C) was as low as 1.0. The addition of MgO promoted the active Ni species to have a good dispersion on the substrate, leading to a better catalytic performance for SMR reaction.

  1. Catalytic steam reforming of tar derived from steam gasification of sunflower stalk over ethylene glycol assisting prepared Ni/MCM-41

    International Nuclear Information System (INIS)

    Highlights: • Ni/MCM-41 was prepared by EG-assisted co-impregnation method. • EG-assisted co-impregnation method resulted in Ni particles well dispersed on MCM-41. • Ni/MCM-41-EG catalyst had high catalytic activity for tar reforming. • The highest H2 gas yield was obtained when using 20 wt.% Ni/MCM-41-EG. • The catalysts were reused up to 5 cycles without any serious deactivation. - Abstract: Ethylene glycol (EG) assisted impregnation of nickel catalyst on MCM-41 (Ni/MCM-41-EG) was performed and applied for steam reforming of tar derived from biomass. The catalyst was characterized by SEM–EDX, BET, XRD, and TPR. It is found that smaller nickel particles were well dispersed on MCM-41 and better catalytic activity was shown for the Ni/MCM-41-EG when compared with the catalyst of Ni/MCM-41 prepared by using the conventional impregnation method. H2 yield increased approximately 8% when using 20 wt.% Ni/MCM-41-EG instead of 20 wt.% Ni/MCM-41 for the steam reforming of tar derived from sunflower stalk. The catalyst reusability was also tested up to five cycles, and no obvious activity reduction was observed. It indicates that EG assisted impregnation method is a good way to prepare metal loaded porous catalyst with high catalytic activity, high loading amount and long-term stability for the tar reforming

  2. Hydrogen production from etanol steam reforming over NiZnAl catalysts

    International Nuclear Information System (INIS)

    The ethanol steam reforming reaction has been studied over NiZnAl catalysts.The catalysts were prepared by the citrate method, with 1 and 8 wt.% of Ni and a Zn:Al molar ratio nearly constant.They were characterized by different techniques such as BET specific surface area, X-ray diffraction, infrared spectroscopy and temperature programmed reduction.The preparation method leads to the formation of a highly crystalline normal spinel (ZnAl2O4) with ZnO segregation.NiO is also observed in the sample with 8 wt.% Ni.The presence of NiAl2O4 cannot be ruled out.Both samples are equally active under reforming conditions with 100% of ethanol conversion at 500 degree C.Hydrogen yield expressed as mol of hydrogen per mol of ethanol increases from 2 to 3, when the Ni loading increases.An important fraction of carbon compounds (C3H6O, C3H6 y C2H4, etc.), besides CO2, CH4 and CO is also observed

  3. Co-Fe-Si Aerogel Catalytic Honeycombs for Low Temperature Ethanol Steam Reforming

    Directory of Open Access Journals (Sweden)

    Montserrat Domínguez

    2012-09-01

    Full Text Available Cobalt talc doped with iron (Fe/Co~0.1 and dispersed in SiO2 aerogel was prepared from silica alcogel impregnated with metal nitrates by supercritical drying. Catalytic honeycombs were prepared following the same procedure, with the alcogel synthesized directly over cordierite honeycomb pieces. The composite aerogel catalyst was characterized by X-ray diffraction, scanning electron microscopy, focus ion beam, specific surface area and X-ray photoelectron spectroscopy. The catalytic layer is about 8 µm thick and adheres well to the cordierite support. It is constituted of talc layers of about 1.5 µm × 300 nm × 50 nm which are well dispersed and anchored in a SiO2 aerogel matrix with excellent mass-transfer properties. The catalyst was tested in the ethanol steam reforming reaction, aimed at producing hydrogen for on-board, on-demand applications at moderate temperature (573–673 K and pressure (1–7 bar. Compared to non-promoted cobalt talc, the catalyst doped with iron produces less methane as byproduct, which can only be reformed at high temperature, thereby resulting in higher hydrogen yields. At 673 K and 2 bar, 1.04 NLH2·mLEtOH(l−1·min−1 are obtained at S/C = 3 and W/F = 390 g·min·molEtOH−1.

  4. Optimization of steam methane reforming coupled with pressure swing adsorption hydrogen production process by heat integration

    International Nuclear Information System (INIS)

    Highlights: • A novel energy-saving H2 production process is exploited. • Heat integration technology is used to recover the wasted heat. • Heat coupling of heat exchangers is optimized in SMR and PSA sections. • Energy consumption is reduced to 39.5% that of the conventional process. - Abstract: Hydrogen has been widely researched as a promising alternative fuel. Steam methane reforming (SMR) coupled with pressure swing adsorption (PSA) is one of the most dominant processes for hydrogen production. In order to reduce the energy consumption, a novel energy saving SMR–PSA H2 production process by combining heat integration technology has been put forward. In SMR section, the waste heat of reformer and water–gas-shift (WGS) reactors is recovered to pre-heat feed gas and H2O. In the view of exergy, a compressor is used to achieve a well heat pairing of sensible and latent heat between hot and cold streams. In PSA section, the generated adsorption heat is recovered by heat pump and reused for regeneration of sorbent. In the total process, optimal heat coupling between hot and cold streams is realized. The simulation results indicated that the SMR and PSA sections in the optimized hydrogen production process can save 55.77 kJ/mol H2 and 6.01 kJ/mol H2, respectively. The total energy consumption of the novel SMR–PSA process can be reduced to 39.5% that of the conventional process

  5. Effects of electric current upon catalytic steam reforming of biomass gasification tar model compounds to syngas

    International Nuclear Information System (INIS)

    Highlights: • ECR technique was proposed to convert biomass gasification tar model compounds. • Electric current enhanced the reforming efficiency remarkably. • The highest toluene conversion reached 99.9%. • Ni–CeO2/γ-Al2O3 exhibited good stability during the ECR performance. - Abstract: Electrochemical catalytic reforming (ECR) technique, known as electric current enhanced catalytic reforming technique, was proposed to convert the biomass gasification tar into syngas. In this study, Ni–CeO2/γ-Al2O3 catalyst was prepared, and toluene was employed as the major feedstock for ECR experiments using a fixed-bed lab-scale setup where thermal electrons could be generated and provided to the catalyst. Several factors, including the electric current intensity, reaction temperature and steam/carbon (S/C) ratio, were investigated to reveal their effects on the conversion of toluene as well as the composition of the gas products. Moreover, toluene, two other tar model compounds (benzene and 1-methylnaphthalene) and real tar (tar-containing wastewater) were subjected to the long period catalytic stability tests. All the used catalysts were analyzed to determine their carbon contents. The results indicated that the presence of electric current enhanced the catalytic performance remarkably. The toluene conversion reached 99.9% under the electric current of 4 A, catalytic temperature of 800 °C and S/C ratio of 3. Stable conversion performances of benzene, 1-methylnaphthalene and tar-containing wastewater were also observed in the ECR process. H2 and CO were the major gas products, while CO2 and CH4 were the minor ones. Due to the promising capability, the ECR technique deserves further investigation and application for efficient tar conversion

  6. Bench scale flotation of spodume/quartz and lepidolite/quartz synthetic mixtures

    International Nuclear Information System (INIS)

    Based on results of zeta potential determinations and microflotation tests, bench scale flotation experiments were carried out using spodume/quartz and lepodolite/quartz synthetic mixtures. Pure natural samples, further purified in laboratory, and commercial reagents were employed. The minerals were characterized by X-ray diffraction technique. Selectivity between spodume and quartz was achieved through modification with corn starch and between lepidolite and quartz through pH control in the acidic range. (Author)

  7. Hydrogen production by enhanced-sorption chemical looping steam reforming of glycerol in moving-bed reactors

    International Nuclear Information System (INIS)

    Highlights: • New approach on continuous high-purity H2 produced auto-thermally with long time. • Low-cost NiO/NiAl2O4 exhibited high redox performance to H2 from glycerol. • Oxidation, steam reforming, WSG and CO2 capture were combined into a reactor. • H2 purity of above 90% was produced without heating at 1.5–3.0 S/C and 500–600 °C. • Sorbent regeneration and catalyst oxidization achieved simultaneously in a reactor. - Abstract: The continuous high-purity hydrogen production by the enhanced-sorption chemical looping steam reforming of glycerol based on redox reactions integrated with in situ CO2 removal has been experimentally studied. The process was carried out by a flow of catalyst and sorbent mixture using two moving-bed reactors. Various unit operations including oxidation, steam reforming, water gas shrift reaction and CO2 removal were combined into a single reactor for hydrogen production in an overall economic and efficient process. The low-cost NiO/NiAl2O4 catalyst efficiently converted glycerol and steam to H2 by redox reactions and the CO2 produced in the process was simultaneously removed by CaO sorbent. The best results with an enriched hydrogen product of above 90% in auto-thermal operation for reforming reactor were achieved at initial temperatures of 500–600 °C and ratios of steam to carbon (S/C) of 1.5–3.0. The results indicated also that not all of NiO in the catalyst can be reduced to Ni by the reaction with glycerol, and the reduced Ni can be oxidized to NiO by air at 900 °C. The catalyst oxidization and sorbent regeneration were achieved under the same conditions in air reactor

  8. Embedded Sensors and Controls to Improve Component Performance and Reliability -- Bench-scale Testbed Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Melin, Alexander M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kisner, Roger A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Drira, Anis [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Reed, Frederick K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-09-01

    Embedded instrumentation and control systems that can operate in extreme environments are challenging due to restrictions on sensors and materials. As a part of the Department of Energy's Nuclear Energy Enabling Technology cross-cutting technology development programs Advanced Sensors and Instrumentation topic, this report details the design of a bench-scale embedded instrumentation and control testbed. The design goal of the bench-scale testbed is to build a re-configurable system that can rapidly deploy and test advanced control algorithms in a hardware in the loop setup. The bench-scale testbed will be designed as a fluid pump analog that uses active magnetic bearings to support the shaft. The testbed represents an application that would improve the efficiency and performance of high temperature (700 C) pumps for liquid salt reactors that operate in an extreme environment and provide many engineering challenges that can be overcome with embedded instrumentation and control. This report will give details of the mechanical design, electromagnetic design, geometry optimization, power electronics design, and initial control system design.

  9. Thermal inactivation of Bacillus anthracis surrogate spores in a bench-scale enclosed landfill gas flare.

    Science.gov (United States)

    Tufts, Jenia A McBrian; Rosati, Jacky A

    2012-02-01

    A bench-scale landfill flare system was designed and built to test the potential for landfilled biological spores that migrate from the waste into the landfill gas to pass through the flare and exit into the environment as viable. The residence times and temperatures of the flare were characterized and compared to full-scale systems. Geobacillus stearothermophilus and Bacillus atrophaeus, nonpathogenic spores that may serve as surrogates for Bacillus anthracis, the causative agent for anthrax, were investigated to determine whether these organisms would be inactivated or remain viable after passing through a simulated landfill flare. High concentration spore solutions were aerosolized, dried, and sent through a bench-scale system to simulate the fate of biological weapon (BW)-grade spores in a landfill gas flare. Sampling was conducted downstream of the flare using a bioaerosol collection device containing sterile white mineral oil. The samples were cultured, incubated for seven days, and assessed for viability. Results showed that the bench-scale system exhibited good similarity to the real-world conditions of an enclosed standard combustor flare stack with a single orifice, forced-draft diffusion burner. All spores of G. stearothermophilus and B. atrophaeus were inactivated in the flare, indicating that spores that become re-entrained in landfill gas may not escape the landfill as viable, apparently becoming completely inactivated as they exit through a landfill flare. PMID:22442931

  10. Embedded Sensors and Controls to Improve Component Performance and Reliability -- Bench-scale Testbed Design Report

    International Nuclear Information System (INIS)

    Embedded instrumentation and control systems that can operate in extreme environments are challenging due to restrictions on sensors and materials. As a part of the Department of Energy's Nuclear Energy Enabling Technology cross-cutting technology development programs Advanced Sensors and Instrumentation topic, this report details the design of a bench-scale embedded instrumentation and control testbed. The design goal of the bench-scale testbed is to build a re-configurable system that can rapidly deploy and test advanced control algorithms in a hardware in the loop setup. The bench-scale testbed will be designed as a fluid pump analog that uses active magnetic bearings to support the shaft. The testbed represents an application that would improve the efficiency and performance of high temperature (700 C) pumps for liquid salt reactors that operate in an extreme environment and provide many engineering challenges that can be overcome with embedded instrumentation and control. This report will give details of the mechanical design, electromagnetic design, geometry optimization, power electronics design, and initial control system design.

  11. Design and fabrication of a glovebox for the Plasma Hearth Process radioactive bench-scale system

    International Nuclear Information System (INIS)

    This paper presents some of the design considerations and fabrication techniques for building a glovebox for the Plasma Hearth Process (PHP) radioactive bench-scale system. The PHP radioactive bench-scale system uses a plasma torch to process a variety of radioactive materials into a final vitrified waste form. The processed waste will contain plutonium and trace amounts of other radioactive materials. The glovebox used in this system is located directly below the plasma chamber and is called the Hearth Handling Enclosure (HHE). The HHE is designed to maintain a confinement boundary between the processed waste and the operator. Operations that take place inside the HHE include raising and lowering the hearth using a hydraulic lift table, transporting the hearth within the HHE using an overhead monorail and hoist system, sampling and disassembly of the processed waste and hearth, weighing the hearth, rebuilding a hearth, and sampling HEPA filters. The PHP radioactive bench-scale system is located at the TREAT facility at Argonne National Laboratory-West in Idaho Falls, Idaho

  12. Manual of procedures for the operation of bench-scale anaerobic digesters

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, R.R.

    1978-12-01

    The successful operation of any laboratory-scale biological system is often a difficult and frustrating experience. This is especially true when dealing with the anaerobic digestion process. Because of the stringent environmental requirements associated with anaerobic digesters, efficient operation of bench-scale units requires rigid monitoring and control. The purpose of this manual is to present the methods and procedures which are followed in bench-scale anaerobic digestion studies at Pacific Northwest Laboratory (PNL). Among the topics discussed are operating parameters, a description of the experimental system, typical digestion substrates, operational procedures, analytical techniques, and safety considerations. The document serves as a technical guide to PNL personnel assigned to a U.S. Department of Energy sponsored program evaluating the effect of powdered activated carbon on the anaerobic digestio of sewage sludge. It should be noted that the methods described in this manual do not necessarily represent the best or only means of conducting the research. They are merely procedures that have been found to be successful at PNL. It is hoped that this information may be useful to other researchers who are contemplating or pursuing bench-scale studies of their own.

  13. SUMMARY PLAN FOR BENCH-SCALE REFORMER AND PRODUCT TESTING TREATABILITY STUDIES USING HANFORD TANK WASTE

    Energy Technology Data Exchange (ETDEWEB)

    ROBBINS RA

    2011-02-11

    This paper describes the sample selection, sample preparation, environmental, and regulatory considerations for shipment of Hanford radioactive waste samples for treatability studies of the FBSR process at the Savannah River National Laboratory and the Pacific Northwest National Laboratory.

  14. Summary Plan For Bench-Scale Reformer And Product Testing Treatability Studies Using Hanford Tank Waste

    International Nuclear Information System (INIS)

    This paper describes the sample selection, sample preparation, environmental, and regulatory considerations for shipment of Hanford radioactive waste samples for treatability studies of the FBSR process at the Savannah River National Laboratory and the Pacific Northwest National Laboratory.

  15. Steam reforming of CH4 over Ni-Ru catalysts supported on Mg-Al mixed oxide

    OpenAIRE

    Takehira, Katsuomi; Ohi, Takenori; Miyata, Takeshi; Shiraga, Masato; Sano, Tsuneji

    2007-01-01

    Ni0.5/Mg2.5(Al)O catalyst prepared from hydrotalcite precursors showed high and stable activity in the CH4 steam reforming, but was severely deactivated in the daily start-up and shut-down (DSS) operation under steam purging. The addition of Ru drastically improved the behavior of Ni0.5/Mg2.5(Al)O catalyst for the DSS operation. During the wet Ru loading on the Ni0.5/Mg2.5(Al)O catalyst, the reconstitution of hydrotalcite took place by "memory effect," resulting in the formation of Ru-Ni allo...

  16. A Feasibility Study of a Steam Methane Reforming Hydrogen Production Plant with a Sodium-Cooled Fast Reactor

    International Nuclear Information System (INIS)

    A thermal source for hydrogen production is an attractive utilization of nuclear energy. Hydrogen production from natural gas is a promising method in an early stage of hydrogen society, though hydrogen production with water splitting without carbon dioxide emission is the final goal. Steam methane reforming is a well-known method for producing hydrogen from natural gas. A hydrogen separation membrane makes the reforming temperature much lower than that of the equilibrium condition, and a sodium-cooled fast reactor, which supplies heat at ∼500 deg. C, can be used as a heat source for hydrogen production.In this study, a hydrogen production plant with the membrane reforming method using a sodium-cooled reactor as a thermal source has been designed, and its economic potential is roughly evaluated. The hydrogen production cost is estimated to be about $1.67/kg, achieving the economic target of $1.7/kg. The construction cost is largely shared by the reformers' cost, and it can be decreased using a more efficient hydrogen separation membrane. This shows that steam methane reforming hydrogen production with a sodium-cooled reactor has high economical potential

  17. Development of steam-methane reforming (SMR) membrane reactor for hydrogen production in ICIT - Rm. Valcea, Romania

    International Nuclear Information System (INIS)

    The hydrogen economy has enormous societal and technical appeal as a potential solution to the fundamental energy concerns of abundant supply and minimal environmental impact. Generation of pure hydrogen represents a critical technology component for power generation by PEM fuel cells in a variety of mobile and stationary power applications. Hydrogen is conventionally produced by steam reforming of hydrocarbon fuels followed by a water gas shift reaction and hydrogen separation and purification. One of the newest fields of research and technical applications is to combine the reformer reactor and the hydrogen purification steps into a single membrane reactor. (authors)

  18. EFRT M12 Issue Resolution: Comparison of PEP and Bench-Scale Oxidative Leaching Results

    Energy Technology Data Exchange (ETDEWEB)

    Rapko, Brian M.; Brown, Christopher F.; Eslinger, Paul W.; Fountain, Matthew S.; Hausmann, Tom S.; Huckaby, James L.; Hanson, Brady D.; Kurath, Dean E.; Minette, Michael J.

    2009-08-14

    20 wt% solids using cross-flow ultrafiltration before the addition of caustic. For wastes that have significantly high chromium content, the caustic leaching and slurry dewatering is followed by adding sodium permanganate to UFP-VSL-T02A, and the slurry is subjected to oxidative leaching at nominally ambient temperature. The purpose of the oxidative leaching is to selectively oxidize the poorly alkaline-soluble Cr(III) believed to be the insoluble form in Hanford tank sludge to the much more alkaline-soluble Cr(VI), e.g., chromate. The work described in this report provides the test results that are related to the efficiency of the oxidative leaching process to support process modeling based on tests performed with a Hanford waste simulant. The tests were completed both at the lab-bench scale and in the PEP. The purpose of this report is to summarize the results from both scales that are related to oxidative leaching chemistry to support a scale factor for the submodels to be used in the G2 model, which predicts WTP operating performance. Owing to schedule constraints, the PEP test data to be included in this report are limited to those from Integrated Tests A (T01 A/B caustic leaching) and B (T02A caustic leaching).

  19. Thermodynamic comparison of two processes of hydrogen production: steam methane reforming-A solar thermochemical process

    International Nuclear Information System (INIS)

    Hydrogen is mainly employed like primary product, for the synthesis of ammonia. The ammonia is synthesized by chemically combining hydrogen and nitrogen under pressure, in the presence of a catalyst. This ammonia is used, for the production of the nitrate fertilizers. Nowadays hydrogen gains more attention mainly because, it is regarded as a future significant fuel by much of experts. The widespread use of hydrogen as source of energy could help to reduce the concern concerning the safety of energy, the total change of climate and the quality of air. Hydrogen is presented then as an excellent alternate initially and as substitute thereafter. It can play a role even more significant than conventional energies. Indeed, it has the advantage of being nonpolluting and it can use the same means of transport as conventional energies. For Algeria, it proves of importance capital. It not only makes it possible to increase and diversify its energy reserves and its exports but also to provide for its energy needs which become increasingly significant. Although hydrogen can be produced starting from a large variety of resources using a range of various technologies, the natural gas is generally preferred and will remain in the near future the principal primary product for the manufacture of hydrogen. Currently the most effective means of production of hydrogen is the Steam Reforming of Natural Gas (SMR). This process is seen as a one of principal technologies for the production of hydrogen. The disadvantages of this process it's that it consumes a great quantity of primary energy and that it releases in the atmosphere the gases that contribute to the warming of the plane. Among the alternatives processes of hydrogen production one can quote solar thermochemical processes. In this study, an exergetic analysis of the process of hydrogen production based on Zn/ZnO redox reactions is presented. In the first part of this study, an exergetic analysis is made for a temperature of the

  20. Fluidized Bed Steam Reforming of Hanford LAW Using THORsm Mineralizing Technology

    International Nuclear Information System (INIS)

    The U.S. Department of Energy (DOE) documented, in 2002, a plan for accelerating cleanup of the Hanford Site, located in southeastern Washington State, by at least 35 years. A key element of the plan was acceleration of the tank waste program and completion of tank waste treatment by 2028 by increasing the capacity of the planned Waste Treatment Plant (WTP) and using supplemental technologies for waste treatment and immobilization. The plan identified steam reforming technology as a candidate for supplemental treatment of as much as 70% of the low-activity waste (LAW). Mineralizing steam reforming technology, offered by THOR Treatment Technologies, LLC would produce a denitrated, granular mineral waste form using a high-temperature fluidized bed process. A pilot scale demonstration of the technology was completed in a 15-cm-diameter reactor vessel. The pilot scale facility was equipped with a highly efficient cyclone separator and heated sintered metal filters for particulate removal, a thermal oxidizer for reduced gas species and NOx destruction, and a packed activated carbon bed for residual volatile species capture. The pilot scale equipment is owned by the DOE, but located at the Science and Technology Applications Research (STAR) Center in Idaho Falls, ID. Pilot scale testing was performed August 2-5, 2004. Flowsheet chemistry and operational parameters were defined through a collaborative effort involving Idaho National Engineering and Environmental Laboratory, Savannah River National Laboratory (SRNL), and THOR Treatment Technologies personnel. Science Application International Corporation, owners of the STAR Center, personnel performed actual pilot scale operation. The pilot scale test achieved a total of 68.7 hrs of cumulative/continuous processing operation before termination in response to a bed de-fluidization condition. 178 kg of LAW surrogate were processed that resulted in 148 kg of solid product, a mass reduction of about 17%. The process achieved

  1. Fluidized Bed Steam Reforming of Hanford LAW Using THORsm Mineralizing Technology

    Energy Technology Data Exchange (ETDEWEB)

    Olson, Arlin L.; Nicholas R Soelberg; Douglas W. Marshall; Gary L. Anderson

    2004-11-01

    The U.S. Department of Energy (DOE) documented, in 2002, a plan for accelerating cleanup of the Hanford Site, located in southeastern Washington State, by at least 35 years. A key element of the plan was acceleration of the tank waste program and completion of ''tank waste treatment by 2028 by increasing the capacity of the planned Waste Treatment Plant (WTP) and using supplemental technologies for waste treatment and immobilization.'' The plan identified steam reforming technology as a candidate for supplemental treatment of as much as 70% of the low-activity waste (LAW). Mineralizing steam reforming technology, offered by THOR Treatment Technologies, LLC would produce a denitrated, granular mineral waste form using a high-temperature fluidized bed process. A pilot scale demonstration of the technology was completed in a 15-cm-diameter reactor vessel. The pilot scale facility was equipped with a highly efficient cyclone separator and heated sintered metal filters for particulate removal, a thermal oxidizer for reduced gas species and NOx destruction, and a packed activated carbon bed for residual volatile species capture. The pilot scale equipment is owned by the DOE, but located at the Science and Technology Applications Research (STAR) Center in Idaho Falls, ID. Pilot scale testing was performed August 2–5, 2004. Flowsheet chemistry and operational parameters were defined through a collaborative effort involving Idaho National Engineering and Environmental Laboratory, Savannah River National Laboratory (SRNL), and THOR Treatment Technologies personnel. Science Application International Corporation, owners of the STAR Center, personnel performed actual pilot scale operation. The pilot scale test achieved a total of 68.7 hrs of cumulative/continuous processing operation before termination in response to a bed de-fluidization condition. 178 kg of LAW surrogate were processed that resulted in 148 kg of solid product, a mass reduction of about 17%. The process

  2. Stable Hydrogen Production from Ethanol through Steam Reforming Reaction over Nickel-Containing Smectite-Derived Catalyst

    Directory of Open Access Journals (Sweden)

    Hiroshi Yoshida

    2014-12-01

    Full Text Available Hydrogen production through steam reforming of ethanol was investigated with conventional supported nickel catalysts and a Ni-containing smectite-derived catalyst. The former is initially active, but significant catalyst deactivation occurs during the reaction due to carbon deposition. Side reactions of the decomposition of CO and CH4 are the main reason for the catalyst deactivation, and these reactions can relatively be suppressed by the use of the Ni-containing smectite. The Ni-containing smectite-derived catalyst contains, after H2 reduction, stable and active Ni nanocrystallites, and as a result, it shows a stable and high catalytic performance for the steam reforming of ethanol, producing H2.

  3. Nickel-carbon nanocomposites prepared using castor oil as precursor: A novel catalyst for ethanol steam reforming

    Science.gov (United States)

    Carreño, Neftalí L. V.; Garcia, Irene T. S.; Raubach, Cristiane W.; Krolow, Mateus; Santos, Cláudia C. G.; Probst, Luiz F. D.; Fajardo, Humberto V.

    A novel and simple method to prepare nickel-based catalysts for ethanol steam reforming is proposed. The present method was developed using castor oil as a precursor. The results clarify that the nickel-carbon (Ni/C) catalyst has a high activity for ethanol steam reforming. It was observed that the catalytic behavior could be modified according to the experimental conditions employed. Moreover, it is interesting to note that the increase in the catalytic activity of the Ni/C nanocomposite over time, at 500 and 600 °C of reaction temperature, may be associated with the formation of filamentous carbon. The preliminary results indicate that the novel methodology used, led to the obtainment of materials with important properties that can be extended to applications in different catalytic process.

  4. Steam reforming of ethanol over bimetallic RhPt/La2O3: Long-term stability under favorable reaction conditions

    OpenAIRE

    Cobo, Martha; Pieruccini, Diana; Abello, Ricardo; Ariza, Laura; Córdoba, Luis Fernando; Conesa Ferrer, Juan Antonio

    2013-01-01

    Recently, the steam reforming of biofuels has been presented as a potential hydrogen source for fuel cells. Because this scenario represents an interesting opportunity for Colombia (South America), which produces large amounts of bioethanol, the steam reforming of ethanol was studied over a bimetallic RhPt/La2O3 catalyst under bulk mass transfer conditions. The effect of temperature and the initial concentrations of ethanol and water were evaluated at space velocities above 55,000 h−1 to dete...

  5. Methanol steam reforming via internal recycle reactor. Paper no. IGEC-1-144

    International Nuclear Information System (INIS)

    Hydrogen generation for PEMFC by methanol steam reforming using a Caldwell internal recycle reactor (IRR) was studied. BASF K3-110 copper-based catalyst was used. The impeller speed and methanol retention time almost proportionally affected the recycle ratio, one of the most direct and important indices to show the gradientlessness of concentration and temperature. When the recycle ratio was greater than 20, internal recycle reactor could be considered as continuously stirred tank reactor (CSTR), one ideal reactor for kinetics studies with no appreciable concentration and temperature gradients. The experiment results via CSTR fit very well with the kinetics model developed using a differential reactor by Peppley et al.. This verified the accuracy of the Peppley model and vice versa. The pseudo first order reaction rate constant developed in the CSTR was found to be 0.1-0.15 mol/bar.kg.s, and the activation energy was 93 kJ/mol, which were in good accordance with Peppley model and other values reported in the literature. However, when the recycle ratio was too low, less than 20 for instance, either because of the high GHSV of reactants or low impeller speed, methanol conversion rate as well as CO2, H2 production rates were well below the values predicted by the Peppley model due to the existence of strong gradients of concentration and temperature. Regardless of the recycle ratio, CO producing rate in the IRR was lower than that via the plug flow reactor (PFR) in terms of Peppley model, which could be presumably ascribed to the strong inhibition effect of hydrogen on the reaction rate of methanol decomposition and reverse water gas shift (WGS) reaction over Cu based catalyst. This characteristic could be of benefit in reactor design to suppress CO yield which will be beneficial for producing PEMFC-grade reformate. (author)

  6. Hydrogen production from steam reforming of acetic acid over Cu-Zn supported calcium aluminate.

    Science.gov (United States)

    Mohanty, Pravakar; Patel, Madhumita; Pant, Kamal K

    2012-11-01

    Hydrogen can be produced by catalytic steam reforming (CSR) of biomass-derived oil. Typically bio oil contains 12-14% acetic acid; therefore, this acid was chosen as model compound for reforming of biooil with the help of a Cu-Zn/Ca-Al catalyst for high yield of H(2) with low CH(4) and CO content. Calcium aluminate support was prepared by solid-solid reaction at 1350°C. X-ray diffraction indicates 12CaO·7Al(2)O(3) as major, CaA(l4)O(7) and Ca(5)A(l6)O(14) as minor phases. Cu and Zn were loaded onto the support by wet-impregnation at 10 and 1wt.%, respectively. The catalysts were characterized by Brunauer-Emmett-Teller (BET), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy TEM and the surface area for both support and Cu-Zn were 10.5 and 5.8m(2)/g, respectively. CSR was carried out in a tubular fixed bed reactor (I.D.=19mm) at temperatures between 600 and 800°C with 3-g loadings and (H(2)O/acetic acid) wt. ratio of 9:1. Significantly high (80%) yield of hydrogen was obtained over Cu-Zn/Ca-Al catalyst, as incorporation of Zn enhanced the H(2) yield by reducing deactivation of the catalyst. The coke formation on the support (Ca-12/Al-7) surface was negligible due to the presence of excess oxygen in the 12CaO·7Al(2)O(3) phase. PMID:22944490

  7. Stable Hydrogen Production from Ethanol through Steam Reforming Reaction over Nickel-Containing Smectite-Derived Catalyst

    OpenAIRE

    Hiroshi Yoshida; Ryohei Yamaoka; Masahiko Arai

    2014-01-01

    Hydrogen production through steam reforming of ethanol was investigated with conventional supported nickel catalysts and a Ni-containing smectite-derived catalyst. The former is initially active, but significant catalyst deactivation occurs during the reaction due to carbon deposition. Side reactions of the decomposition of CO and CH4 are the main reason for the catalyst deactivation, and these reactions can relatively be suppressed by the use of the Ni-containing smectite. The Ni-containing ...

  8. Experimental and Modeling Studies of the Methane Steam Reforming Reaction at High Pressure in a Ceramic Membrane Reactor

    OpenAIRE

    Hacarlioglu, Pelin

    2007-01-01

    This dissertation describes the preparation of a novel inorganic membrane for hydrogen permeation and its application in a membrane reactor for the study of the methane steam reforming reaction. The investigations include both experimental studies of the membrane permeation mechanism and theoretical modeling of mass transfer through the membrane and simulation of the membrane reactor with 1-D and 2-D models. A hydrothermally stable and hydrogen selective membrane composed of silica and a...

  9. Surface Reaction Kinetics of Steam- and CO2-Reforming as Well as Oxidation of Methane over Nickel-Based Catalysts

    OpenAIRE

    Karla Herrera Delgado; Lubow Maier; Steffen Tischer; Alexander Zellner; Henning Stotz; Olaf Deutschmann

    2015-01-01

    An experimental and kinetic modeling study on the Ni-catalyzed conversion of methane under oxidative and reforming conditions is presented. The numerical model is based on a surface reaction mechanism consisting of 52 elementary-step like reactions with 14 surface and six gas-phase species. Reactions for the conversion of methane with oxygen, steam, and CO2 as well as methanation, water-gas shift reaction and carbon formation via Boudouard reaction are included. The mechanism is implemented i...

  10. Experimental facilities for the investigation of hydrogen and tritium permeation problems involved with steam methane reforming by nuclear process heat

    International Nuclear Information System (INIS)

    Problems of the permeation of hydrogen and tritium through heat exchangers for HTGR reactors and for steam/methane reforming processes in which nuclear heat is used, are discussed. An experimental facility is described which was designed to investigate hydrogen permeability through materials of interest at the high temperature involved under process conditions and results of the tests are presented. Plans are also discussed for determination of permeation of tritium, produced in the HTR, into the chemical products. (U.K.)

  11. Enhanced hydrogen production from methane steam reforming using a new thin layered structural coating on a metal substrate

    OpenAIRE

    Lugo, Michael; Tiliakos, Nickolas; Wilde, Juray De; Gill, Rajinder; W. Davis, Andrew; Soltani, Elaine C.; Modroukas, Dean; Castaldi, Marco J.; AICHE 2015 Annual Meeting

    2015-01-01

    The recent increase in the availability of hydrocarbons, especially methane, from shale gas exploration has led to renewed interest in converting or upgrading methane to higher value chemicals. Steam reforming is still the most developed and widely practiced industrial process for converting methane to hydrogen/syngas and its derivatives. It has no oxygen requirement and the most favorable H2/CO ratio for methanol and ammonia production of all available technologies. However, opportunities st...

  12. Steam reforming of ethanol over Ni/support catalysts for generation of hydrogen for fuel cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Denis, Andrzej; Grzegorczyk, Wieslaw; Gac, Wojciech; Machocki, Andrzej [University of Maria Curie-Sklodowska, Faculty of Chemistry, Department of Chemical Technology, 3 Maria Curie-Sklodowska Square, 20-031 Lublin (Poland)

    2008-09-30

    The paper reports experimental results concerning the influence of the support nature (TiO{sub 2}, ZnO, Al{sub 2}O{sub 3} and Al{sub 2}O{sub 3}-Fe{sub 2}O{sub 3}) of nickel catalysts on their activity, selectivity and coking phenomenon in the steam reforming of ethanol in the range of 570-870K. The chemical transformations of ethanol occurring on the catalyst support make its chemical nature an important factor affecting the productivity and selectivity of the process. It was found that the most suitable supports in nickel catalysts designed for hydrogen generation in the steam reforming of ethanol are ZnO and TiO{sub 2}. Taking into consideration both the efficiency of hydrogen generation and the intensity of carbon deposition, the optimum temperature of the process of the steam reforming of ethanol is below 750K. An improvement in the selectivity of hydrogen generation and diminishing of the formation of undesirable products may be obtained by promoting nickel catalysts with sodium. (author)

  13. Model biogas steam reforming in a thin Pd-supported membrane reactor to generate clean hydrogen for fuel cells

    Science.gov (United States)

    Iulianelli, A.; Liguori, S.; Huang, Y.; Basile, A.

    2015-01-01

    Steam reforming of a model biogas mixture is studied for generating clean hydrogen by using an inorganic membrane reactor, in which a composite Pd/Al2O3 membrane separates part of the produced hydrogen through its selective permeation. The characteristics of H2 perm-selectivity of the fresh membrane is expressed in terms of H2/N2 ideal selectivity, in this case equal to 4300. Concerning biogas steam reforming reaction, at 380 °C, 2.0 bar H2O:CH4 = 3:1, GHSV = 9000 h-1 the permeate purity of the recovered hydrogen is around 96%, although the conversion (15%) and hydrogen recovery (>20%) are relatively low; on the contrary, at 450 °C, 3.5 bar H2O:CH4 = 4:1, GHSV = 11000 h-1 the conversion is increased up to more than 30% and the recovery of hydrogen to about 70%. This novel work constitutes a reference study for new developments on biogas steam reforming reaction in membrane reactors.

  14. Methanol steam reforming promoted by molten salt-modified platinum on alumina catalysts.

    Science.gov (United States)

    Kusche, Matthias; Agel, Friederike; Ní Bhriain, Nollaig; Kaftan, Andre; Laurin, Mathias; Libuda, Jörg; Wasserscheid, Peter

    2014-09-01

    We herein describe a straight forward procedure to increase the performance of platinum-on-alumina catalysts in methanol steam reforming by applying an alkali hydroxide coating according to the "solid catalyst with ionic liquid layer" (SCILL) approach. We demonstrate by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and temperature-programmed desorption (TPD) studies that potassium doping plays an important role in the catalyst activation. Moreover, the hygroscopic nature and the basicity of the salt modification contribute to the considerable enhancement in catalytic performance. During reaction, a partly liquid film of alkali hydroxides/carbonates forms on the catalyst/alumina surface, thus significantly enhancing the availability of water at the catalytically active sites. Too high catalyst pore fillings with salt introduce a considerable mass transfer barrier into the system as indicated by kinetic studies. Thus, the optimum interplay between beneficial catalyst modification and detrimental mass transfer effects had to be identified and was found on the applied platinum-on-alumina catalyst at KOH loadings around 7.5 mass%. PMID:25124120

  15. Promotion effect of cobalt-based catalyst with rare earth for the ethanol steam reforming

    Energy Technology Data Exchange (ETDEWEB)

    Chiou, Josh Y. Z.; Chen, Ya-Ping; Yu, Shen-Wei; Wang, Chen-Bin [Department of Chemical and Materials Engineering, Chung Cheng Institute of Technology, National Defense University, Tahsi, Taoyuan 33509, Taiwan (China)

    2013-12-16

    Catalytic performance of ethanol steam reforming (ESR) was investigated on praseodymium (Pr) modified ceria-supported cobalt oxide catalyst. The ceria-supported cobalt oxide (Ce-Co) catalyst was prepared by co-precipitation-oxidation (CPO) method, and the doped Pr (5 and 10 wt% loading) catalysts (Pr{sub 5}−Ce−Co and Pr{sub 10}−Ce−Co) were prepared by incipient wetness impregnation method. The reduction pretreatment under 250 and 400 °C (H250 and H400) was also studied. All samples were characterized by XRD, TPR and TEM. Catalytic performance of ESR was tested from 250 to 500 °C in a fixed-bed reactor. The doping of Pr into the ceria lattice has significantly promoted the activity and reduced the coke formation. The products distribution also can be influenced by the different reduction pretreatment. The Pr{sub 10}−Ce−Co−H400 sample is a preferential ESR catalyst, where the hydrogen distribution approaches 73% at 475 °C with less amounts (< 2%) of CO and CH{sub 4}.

  16. Thermodynamic and kinetic model of reforming coke-oven gas with steam

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jiayuan; Zhang, Xiaohui; Chen, Zhuo; Li, Li [School of Energy Science and Engineering, Central South University, Changsha, 932 South Lushan Rd, Hunan 410083 (China)

    2010-07-15

    The experiments of reforming the methane of coke-oven gas with steam were performed. The effects of the thermodynamic factors, such as the H{sub 2}O/CH{sub 4} ratio, the conversion temperature (T) of methane and the reaction time (t), on the methane conversion rate have been investigated. The experimental results show that the H{sub 2}O/CH{sub 4} ratio within the range of 1.1-1.3 and the temperature 1223-1273 K are the reasonable thermodynamic conditions for methane conversion. A methane conversion of more than 95% can be achieved when the H{sub 2}O/CH{sub 4} ratio is 1.2, the conversion temperature is above 1223 K and the conversion time is up to 15 s respectively. In additional, kinetic data of different reaction conditions were measured, and a dynamic model of methane conversion was proposed and verified. All results demonstrated that the results of the dynamic models agree well with the experiments, of which the deviation is less than 1.5%. (author)

  17. Optimization of catalytic glycerol steam reforming to light olefins using Cu/ZSM-5 catalyst

    International Nuclear Information System (INIS)

    Highlights: • Glycerol steam reforming to light olefin using Cu/ZSM-5 process was optimized. • Response surface methodology and multi-objective genetic algorithm were employed. • Second order polynomial model produced adequately fitted experimental data. • Thermodynamic study inferred high temperature requirement for ethylene formation. • Turn-over-frequency at optimized responses is higher than the non-optimized process. - Abstract: Response surface methodology (RSM) and multi-objective genetic algorithm was employed to optimize the process parameters for catalytic conversion of glycerol, a byproduct from biodiesel production, to light olefins using Cu/ZSM-5 catalyst. The effects of operating temperature, weight hourly space velocity (WHSV) and glycerol concentration on light olefins selectivity and yield were observed. Experimental results revealed the data adequately fitted into a second-order polynomial model. The linear temperature and quadratic WHSV terms gave significant effect on both responses. Optimization of both the responses indicated that temperature favouring high light olefin formation lied beyond the experimental design range. The trend in the temperature profile concurred commensurately with the thermodynamic analysis. Multi-objective genetic algorithm was performed to attain a single set of processing parameters that could produce both the highest light olefin selectivity and yield. The turn-over-frequency (TOF) of the optimized responses demonstrated a slightly higher value than the one which was not optimized. Combination of RSM, multi-objective response and thermodynamic is useful to determine the process optimal operating conditions for industrial applications

  18. Preparation of copper catalyst washcoats for methanol steam reforming in microchannels based on nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Pfeifer, P.; Schubert, K. [Institute for Micro Process Engineering, Forschungszentrum Karlsruhe GmbH, POB 3640, 76021 Karlsruhe (Germany); Emig, G. [LTC1, University Erlangen-Nuernberg, Egerlandstrasse 3, 91058 Erlangen (Germany)

    2005-06-07

    The demand of fast load alternations for hydrogen generation by methanol steam reforming for automotive fuel cell application may be met in an excellent manner by microstructured reactors. However, catalyst incorporation is difficult in the micrometer size. By the use of dispersed nanoparticles a washcoating procedure was developed and is explained on the basis of a copper catalyst system. The mixing of CuO particles with other necessary materials like ZnO was examined during high energy ball milling (dry mixing) or dispersing the powders in a solution of cellulose derivatives (wet mixing). For the latter technique the shearing of agglomerates and re-agglomeration were investigated for the pure substances using laser diffraction. The influence of ball milling on particle sizes was determined by adsorption experiments and X-ray diffraction. All mixtures were characterized by temperature programmed reduction (TPR) followed by the measurement of the Cu(0) particle size (X-ray diffraction). A special method based upon X-ray structure analysis was applied for determination of the mixing quality. The relationship between these catalyst properties and additional measurements of the catalyst activity/degradation done was obvious.

  19. Highly loaded Ni-based catalysts for low temperature ethanol steam reforming

    Science.gov (United States)

    Wang, Tuo; Ma, Hongyan; Zeng, Liang; Li, Di; Tian, Hao; Xiao, Shengning; Gong, Jinlong

    2016-05-01

    This paper describes the design of high-loading Ni/Al2O3 catalysts (78 wt% Ni) for low temperature ethanol steam reforming. The catalysts were synthesized via both co-precipitation (COP) and impregnation (IMP) methods. All the catalysts were measured by N2 adsorption-desorption, XRD, H2-TPR, and H2 pulse chemisorption. The characterization results demonstrated that the preparation method and the loading significantly affected the nickel particle size, active nickel surface area and catalytic performance. Over COP catalysts, large nickel particles were presented in nickel aluminum mixed oxides. In comparison, IMP catalysts gained more ``free'' NiO particles with weak interaction with the aluminum oxide. Consequently, COP catalysts yielded smaller nickel particles and larger active nickel surface areas than those of IMP catalysts. High loading is beneficial for obtaining sufficient active nickel sites when nickel particles are dispersed via COP, whereas excessive nickel content is not desired for catalysts prepared by IMP. Specifically, the 78 wt% nickel loaded catalyst synthesized by COP possessed small nickel particles (~6.0 nm) and an abundant active nickel area (35.1 m2 gcat-1). Consequently, COP-78 achieved superior stability with 92% ethanol conversion and ~35% H2 selectivity at 673 K for 30 h despite the presence of a considerable amount of coke.

  20. Sorption-enhanced steam reforming of ethanol: thermodynamic comparison of CO{sub 2} sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Y.J.; Santos, J.C.; Cunha, A.F.; Rodrigues, A.E. [University of Porto, Faculty of Engineering, Department of Chemical Engineering, Associated Laboratory LSRE/LCM, Laboratory of Separation and Reaction Engineering, Porto (Portugal); Diaz Alvarado, F.; Gracia, F. [Universidad de Chile, Facultad de Ingenieria, Departamento de Ingenieria Quimica y Biotecnologia, Laboratorio de Catalisis, Santiago (Chile)

    2012-05-15

    A thermodynamic analysis is performed with a Gibbs free energy minimization method to compare the conventional steam reforming of ethanol (SRE) process and sorption-enhanced SRE (SE-SRE) with three different sorbents, namely, CaO, Li{sub 2}ZrO{sub 3}, and hydrotalcite-like compounds (HTlc). As a result, the use of a CO{sub 2} adsorbent can enhance the hydrogen yield and provide a lower CO content in the product gas at the same time. The best performance of SE-SRE is found to be at 500 C with an HTlc sorbent. Nearly 6 moles hydrogen per mole ethanol can be produced, when the CO content in the vent stream is less than 10 ppm, so that the hydrogen produced via SE-SRE with HTlc sorbents can be directly used for fuel cells. Higher pressures do not favor the overall SE-SRE process due to lower yielding of hydrogen, although CO{sub 2} adsorption is enhanced. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Thermodynamic and kinetic model of reforming coke-oven gas with steam

    International Nuclear Information System (INIS)

    The experiments of reforming the methane of coke-oven gas with steam were performed. The effects of the thermodynamic factors, such as the H2O/CH4 ratio, the conversion temperature (T) of methane and the reaction time (t), on the methane conversion rate have been investigated. The experimental results show that the H2O/CH4 ratio within the range of 1.1-1.3 and the temperature 1223-1273 K are the reasonable thermodynamic conditions for methane conversion. A methane conversion of more than 95% can be achieved when the H2O/CH4 ratio is 1.2, the conversion temperature is above 1223 K and the conversion time is up to 15 s respectively. In additional, kinetic data of different reaction conditions were measured, and a dynamic model of methane conversion was proposed and verified. All results demonstrated that the results of the dynamic models agree well with the experiments, of which the deviation is less than 1.5%.

  2. Hydrogen Production by Methane Steam Reforming Over Ru and Cu Supported on Hydrotalcite Precursors

    International Nuclear Information System (INIS)

    Co6Al2 oxide was prepared using the hydrotalcite route. The obtained solid was thermally stabilized at 500 degC and then impregnated with 5 wt.% copper or 1 wt.% ruthenium nitrate solution followed by calcination at 500degC under an air flow. X-ray diffraction results showed that the calcination of the impregnated solids led to the formation of various oxides (CuO, RuO2, Co3O4, CoAl2O4, CoAl2O4). The different impregnated and non impregnated solids were tested in the methane steam reforming reaction (MSR). Methane conversion did not exceed 5% at 800 degC in the case of the non impregnated solid, whereas the impregnation strongly enhanced the reactivity: ∼ 89% and ∼ 92% conversions were reached at 600 degC for Cu and Ru respectively. The good reactivity of ruthenium impregnated catalyst was attributed to the formation of easily reducible ruthenium and cobalt oxide species at the surface of the support. The addition of ruthenium made the reduction of surface and bulk cobalt oxides possible at lower temperatures. (author)

  3. Investigations of heat supply of a low-capacity natural gas steam reformer; Untersuchungen zur Waermeversorgung eines Erdgas-Dampf-Reformers kleiner Leistung

    Energy Technology Data Exchange (ETDEWEB)

    Gardemann, Ulrich

    2010-07-21

    The author investigated the heat supply of a natural gas steam reformer in a fuel cell heating system for hydrogen production. Heat is normally supplied by a burner which together with the air supply system, sensors and control system makes up the burner system. Aspects like the general function in specific operating conditions, pollutant emissions and reformer efficiency were investigated theoretically and practically. The dissertation starts by describing the technological fundamentals of the fuel cell technology, hydrogen production technology and combustion technology. The focus was on the PEM fuel cell and on steam reforming; both technologies are considered promising options for fuel cell heating systems and resulted in specific requirements on the burner system. For an objective assessment of emissions, emission units were converted from volumetric into fuel energy related. A conversion tool was developed according to VDI 4660. Further, an emission assessment concept for fuel cell heating systems was developed which uses the fuel energy related emission unit mg/kWh and enables accurate assessment of the burner and the whole fuel cell system in terms of pollutant emissions. (orig.)

  4. Characterization of ZrO 2-promoted Cu/ZnO/nano-Al 2O 3 methanol steam reforming catalysts

    Science.gov (United States)

    Jones, Samuel D.; Neal, Luke M.; Everett, Michael L.; Hoflund, Gar B.; Hagelin-Weaver, Helena E.

    2010-10-01

    Three Cu/ZnO/ZrO 2/Al 2O 3 methanol reforming catalysts were investigated using X-ray photoelectron spectroscopy (XPS). The catalysts which contained ZrO 2 from a monoclinic nanoparticle ZrO 2 precursor exhibit both a higher activity toward the methanol steam reforming reaction and a lower CO production rate compared to catalysts composed of an XRD-amorphous ZrO 2 produced by impregnation using a Zr(NO 3) 2 precursor. The presence of a monoclinic phase appears to result in an increased charge transfer between the Zr and Cu species, as evidenced by a relatively electron-rich ZrO 2 phase and a partially oxidized Cu species on reduced catalysts. This electron deficient Cu species is more reactive toward the methanol reforming reaction and partially suppresses CO formation through the reverse water gas shift or methanol decomposition reactions.

  5. Characterization of ZrO2-promoted Cu/ZnO/nano-Al2O3 methanol steam reforming catalysts

    International Nuclear Information System (INIS)

    Three Cu/ZnO/ZrO2/Al2O3 methanol reforming catalysts were investigated using X-ray photoelectron spectroscopy (XPS). The catalysts which contained ZrO2 from a monoclinic nanoparticle ZrO2 precursor exhibit both a higher activity toward the methanol steam reforming reaction and a lower CO production rate compared to catalysts composed of an XRD-amorphous ZrO2 produced by impregnation using a Zr(NO3)2 precursor. The presence of a monoclinic phase appears to result in an increased charge transfer between the Zr and Cu species, as evidenced by a relatively electron-rich ZrO2 phase and a partially oxidized Cu species on reduced catalysts. This electron deficient Cu species is more reactive toward the methanol reforming reaction and partially suppresses CO formation through the reverse water gas shift or methanol decomposition reactions.

  6. The application of inelastic neutron scattering to investigate the steam reforming of methane over an alumina-supported nickel catalyst

    Science.gov (United States)

    McFarlane, Andrew R.; Silverwood, Ian P.; Norris, Elizabeth L.; Ormerod, R. Mark; Frost, Christopher D.; Parker, Stewart F.; Lennon, David

    2013-12-01

    An alumina-supported nickel catalyst, previously used in methane reforming experiments employing CO2 as the oxidant, is applied here in the steam reforming variant of the process. Micro-reactor experiments are used to discern an operational window compatible with sample cells designed for inelastic neutron scattering (INS) experiments. INS spectra are recorded after 6 h reaction of a 1:1 mixture of CH4 and H2O at 898 K. Weak INS spectra are observed, indicating minimal hydrogen retention by the catalyst in this operational regime. Post-reaction, the catalyst is further characterised by powder X-ray diffraction, transmission electron microscopy and Raman scattering. In a comparable fashion to that seen for the ‘dry’ reforming experiments, the catalyst retains substantial quantities of carbon in the form of filamentous coke. The role for hydrogen incorporation by the catalyst is briefly considered.

  7. Boiling behavior of sodium-potassium alloy in a bench-scale solar receiver

    Science.gov (United States)

    Moreno, J. B.; Andraka, C. E.; Moss, T. A.

    During 1989-90, a 75-kW(sub t) sodium reflux pool-boiler solar receiver was successfully demonstrated at Sandia National Laboratories. Significant features of this receiver include the following: (1) boiling sodium as the heat transfer medium, and (2) electric-discharge-machined (EDM) cavities as artificial nucleation sites to stabilize boiling. Since this first demonstration, design of a second-generation pool-boiler receiver that will bring the concept closer to commercialization has begun. For long life, the new receiver uses Haynes Alloy 230. For increased safety factors against film boiling and flooding, it has a refined shape and somewhat larger dimensions. To eliminate the need for trace heating, the receiver will boil the sodium-potassium alloy NaK-78 instead of sodium. To reduce manufacturing costs, it will use one of a number of alternatives to EDM cavities for stabilization of boiling. To control incipient-boiling superheats, especially during hot restarts, it will contain a small amount of inert gas. Before the new receiver design could be finalized, bench-scale tests of some of the proposed changes were necessary. A series of bench-scale pool boilers were built from Haynes Alloy 230 and filled with NaK-78. Various boiling-stabilizer candidates were incorporated into them, including laser-drilled cavities and a number of different sintered-powder-metal coatings. These bench-scale pool boilers have been operated at temperatures up to 750 C, heated by quartz lamps with incident radiant fluxes up to 95 W/sq cm. The effects of various orientations and added gases have been studied. Results of these studies are presented.

  8. Characterization of Japanese cedar bio-oil produced using a bench-scale auger pyrolyzer

    OpenAIRE

    Kato, Yoshiaki; Enomoto, Ryohei; Akazawa, Minami; Kojima, Yasuo

    2016-01-01

    A bench-scale auger reactor was designed for use as a laboratory-scale fast pyrolyzer for producing bio-oil from Japanese cedar. An analytical pyrolysis method was performed simultaneously to determine the distribution of pyrolysis products. The pyrolysis temperature was found to have the greatest influence on the bio-oil characteristics; bio-oil yields increased as the pyrolysis temperature increased from 450 to 550 °C. The concentration of levoglucosan in the bio-oil, however, decreased sig...

  9. Accumulation of uranium, cesium, and radium by microbial cells: bench-scale studies

    International Nuclear Information System (INIS)

    This report describes bench-scale studies on the utilization of microbial cells for the concentration and removal of uranium, radium, and cesium from nuclear processing waste streams. Included are studies aimed at elucidating the basic mechanism of uranium uptake, process development efforts for the use of a combined denitrification-uranium removal process to treat a specific nuclear processing waste stream, and a preliminary investigation of the applicability of microorganisms for the removal of 137Cs and 226Ra from existing waste solutions

  10. 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

  11. Treatment of simulated high-level radioactive waste with formic acid: Bench-scale study on hydrogen evolution

    International Nuclear Information System (INIS)

    At the Savannah River Site, the Defense Waste Processing Facility (DWPF) was constructed to vitrify high-level radioactive liquid waste in borosilicate glass for permanent storage. Formic acid, which serves as both an acid and a reducing agent, is used to treat the washed alkaline sludge during melter feed preparation primarily to improve the processability of the feed and to reduce mercury to its zero state for steam stripping. The high-level sludge is composed of many transition metal hydroxides. Among them, there are small quantities of platinum group metals. During the treatment of simulated sludge with formic acid, significant amounts of hydrogen were generated when the platinum group metals were included in the sludge. Apparently the noble metals in the sludge were reduced to their zero states and caused formic acid to decompose catalytically into hydrogen and carbon dioxide, usually with an induction period. The production of hydrogen gas presented the DWPF with a safety issue. Therefore, the objective of this research was to gain a fundamental understanding of what controlled the hydrogen evolution so that a practical solution to the safety issue could be obtained. A bench-scale parametric study revealed the following: increasing the amount of formic acid added to the sludge increased the hydrogen generation rate dramatically; once the catalysts were activated, the hydrogen generation rate decreased significantly with a lowering of the temperature of the sludge; the relative catalytic activities of the noble metals in the sludge decreased in the following order: rhodium > ruthenium much-gt palladium; ammonium ions were generated catalytically from the reaction between formic acid and nitrate; and when present, the noble metals caused higher upward drifts of the sludge pH

  12. Performance and economic assessments of a solid oxide fuel cell system with a two-step ethanol-steam-reforming process using CaO sorbent

    Science.gov (United States)

    Tippawan, Phanicha; Arpornwichanop, Amornchai

    2016-02-01

    The hydrogen production process is known to be important to a fuel cell system. In this study, a carbon-free hydrogen production process is proposed by using a two-step ethanol-steam-reforming procedure, which consists of ethanol dehydrogenation and steam reforming, as a fuel processor in the solid oxide fuel cell (SOFC) system. An addition of CaO in the reformer for CO2 capture is also considered to enhance the hydrogen production. The performance of the SOFC system is analyzed under thermally self-sufficient conditions in terms of the technical and economic aspects. The simulation results show that the two-step reforming process can be run in the operating window without carbon formation. The addition of CaO in the steam reformer, which runs at a steam-to-ethanol ratio of 5, temperature of 900 K and atmospheric pressure, minimizes the presence of CO2; 93% CO2 is removed from the steam-reforming environment. This factor causes an increase in the SOFC power density of 6.62%. Although the economic analysis shows that the proposed fuel processor provides a higher capital cost, it offers a reducing active area of the SOFC stack and the most favorable process economics in term of net cost saving.

  13. Development and performance of bench-scale reactor for the photocatalytic generation of hydrogen

    International Nuclear Information System (INIS)

    In this study, a new novel bench-scale (5 L) tubular photocatalytic reactor was developed and its feasibility studies were conducted for optimizing the operating variables, namely concentration of sulfide ion, concentration of sulfite ion, pH, catalyst concentration, lamp power, volume of wastewater and recycle flow rates at batch recycle mode for the generation of hydrogen from aqueous sodium sulfide using CdS–ZnS/TiO2 core–shell NPs (nanoparticles). The maximum H2 generation was found at 0.05 M concentration of sulfide ion, 0.2 M concentration of sulfite ion, pH 11.3, 0.5 g/L catalyst concentration and recycle flow rate of 18 L/h. Reusability studies were conducted for analyzing stability of photocatalyst. The results showed that the generation of hydrogen depends on light intensity, photoreactor used, nature of photocatalysts and the operating conditions. - Highlights: • Clean fuel production using solar energy. • Bench-scale tubular photocatalytic reactor was developed. • Operating variables have significant effect

  14. Pyrolysis/Steam Reforming Technology for Treatment of TRU Orphan Wastes

    International Nuclear Information System (INIS)

    Certain transuranic (TRU) waste streams within the Department of Energy (DOE) complex cannot be disposed of at the Waste Isolation Pilot Plant (WIPP) because they do not meet the shipping requirements of the TRUPACT-II or the disposal requirements of the Waste Analysis Plan (WAP) in the WIPP RCRA Part B Permit. These waste streams, referred to as orphan wastes, cannot be shipped or disposed of because they contain one or more prohibited items, such as liquids, volatile organic compounds (VOCs), hydrogen gas, corrosive acids or bases, reactive metals, or high concentrations of polychlorinated biphenyl (PCB), etc. The patented, non-incineration, pyrolysis and steam reforming processes marketed by THOR Treatment Technologies LLC removes all of these prohibited items from drums of TRU waste and produces a dry, inert, inorganic waste material that meets the existing TRUPACT-II requirements for shipping, as well as the existing WAP requirements for disposal of TRU waste at WIPP. THOR Treatment Technologies is a joint venture formed in June 2002 by Studsvik, Inc. (Studsvik) and Westinghouse Government Environmental Services Company LLC (WGES) to further develop and deploy Studsvik's patented THORSM technology within the DOE and Department of Defense (DoD) markets. The THORSM treatment process is a commercially proven system that has treated over 100,000 cu. ft. of nuclear waste from commercial power plants since 1999. Some of this waste has had contact dose rates of up to 400 R/hr. A distinguishing characteristic of the THORSM process for TRU waste treatment is the ability to treat drums of waste without removing the waste contents from the drum. This feature greatly minimizes criticality and contamination issues for processing of plutonium-containing wastes. The novel features described herein are protected by issued and pending patents

  15. THORR Steam Reforming Technology for the Treatment of Complex and Problematic Wastes - 59084

    International Nuclear Information System (INIS)

    Many types of complex radioactive wastes exist, that due to their chemical and radiological characteristics, are problematic to treat using traditional methods. Studsvik has developed the THORR process that has the capability to successfully treat a wide variety of radioactive wastes including those with high organic content, high nitrate and nitrite content, high solids content, and heavy metal bearing. The process produces a dry stable waste form with no liquid effluents and environmentally compliant off-gas emissions, while reducing the overall waste volume. The more than 10 years of successful operations at Studsvik's facility in Erwin, TN USA provides the foundation for the deployment of the THORR steam reforming process for the treatment of many complex wastes. The THORR process has been shown to effectively convert numerous types of U.S. Department of Energy (DOE) liquid radioactive wastes into solid products while providing a final waste form with leach resistance comparable to vitrified glass waste forms. In addition to testing and on-going project work in the U.S., multiple test programs including lab-scale and engineering-scale demonstrations have been successfully completed for several international organizations. This international work has included testing and development work with solid and liquid organic wastes, as well as high nitrate content liquid waste and graphite. In order to better meet the needs of the international market, Studsvik offers a modular form of its THORR process that is transportable to multiple locations, enabling customers to treat a wide variety of waste streams at multiple sites without the need to design and construct multiple treatment facilities. This paper will provide an up to date overview of the THORR technology, its current capabilities, and a summary of current THORR projects. (authors)

  16. Steam reforming of methane over Ni catalysts prepared from hydrotalcite-type precursors:Catalytic activity and reaction kinetics

    Institute of Scientific and Technical Information of China (English)

    Yang Qi; Zhenmin Cheng; Zhiming Zhou

    2015-01-01

    Ni/Mg–Al catalysts derived from hydrotalcite-type precursors were prepared by a co-precipitation technique and applied to steam reforming of methane. By comparison with Ni/γ-Al2O3 and Ni/α-Al2O3 catalysts prepared by in-cipient wetness impregnation, the Ni/Mg–Al catalyst presented much higher activity as a result of higher specific surface area and better Ni dispersion. The Ni/Mg–Al catalyst with a Ni/Mg/Al molar ratio of 0.5:2.5:1 exhibited the highest activity for steam methane reforming and was selected for kinetic investigation. With external and inter-nal diffusion limitations eliminated, kinetic experiments were carried out at atmospheric pressure and over a temperature range of 823–973 K. The results demonstrated that the overal conversion of CH4 and the conversion of CH4 to CO2 were strongly influenced by reaction temperature, residence time of reactants as wel as molar ratio of steam to methane. A classical Langmuir–Hinshelwood kinetic model proposed by Xu and Froment (1989) fitted the experimental data with excellent agreement. The estimated adsorption parameters were consistent thermodynamical y.

  17. Comparative Investigation of Benzene Steam Reforming over Spinel Supported Rh and Ir Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Mei, Donghai; Lebarbier, Vanessa MC; Rousseau, Roger J.; Glezakou, Vassiliki Alexandra; Albrecht, Karl O.; Kovarik, Libor; Flake, Matthew D.; Dagle, Robert A.

    2013-06-01

    In a combined experimental and first-principles density functional theory (DFT) study, benzene steam reforming (BSR) over MgAl2O4 supported Rh and Ir catalysts was investigated. Experimentally, it has been found that both highly dispersed Rh and Ir clusters (1-2 nm) on the MgAl2O4 spinel support are stable during the BSR in the temperature range of 700-850˚C. Compared to the Ir/MgAl2O4 catalyst, the Rh/MgAl2O4 catalyst is more active with higher benzene turnover frequency and conversion. At typical steam conditions with the steam-to-carbon ratio > 12, the benzene conversion is only a weak function of the H2O concentration in the feed. This suggests that the initial benzene decomposition step rather than the benzene adsorption is most likely the rate-determined step in BSR over supported Rh and Ir catalysts. In order to understand the differences between the two catalysts, we followed with a comparative DFT study of initial benzene decomposition pathways over two representative model systems for each supported metal (Rh and Ir) catalysts. A periodic terrace (111) surface and an amorphous 50-atom metal cluster with a diameter of 1.0 nm were used to represent the two supported model catalysts under low and high dispersion conditions. Our DFT results show that the decreasing catalyst particle size enhances the benzene decomposition on supported Rh catalysts by lowering both C-C and C-H bond scission. The activation barriers of the C-C and the C-H bond scission decrease from 1.60 and 1.61 eV on the Rh(111) surface to 1.34 and 1.26 eV on the Rh50 cluster. For supported Ir catalysts, the decreasing particle size only affects the C-C scission. The activation barrier of the C-C scission of benzene decreases from 1.60 eV on the Ir(111) surface to 1.35 eV on the Ir50 cluster while the barriers of the C-H scission are practically the same. The experimentally measured higher BSR activity on the supported highly dispersed Rh catalyst can be rationalized by the thermodynamic

  18. Steam reforming of ethanol over Co3O4–Fe2O3 mixed oxides

    KAUST Repository

    Abdelkader, A.

    2013-05-03

    Co3O4, Fe2O3 and a mixture of the two oxides Co-Fe (molar ratio of Co3O4/Fe 2O3 = 0.67 and atomic ratio of Co/Fe = 1) were prepared by the calcination of cobalt oxalate and/or iron oxalate salts at 500 C for 2 h in static air using water as a solvent/dispersing agent. The catalysts were studied in the steam reforming of ethanol to investigate the effect of the partial substitution of Co3O4 with Fe2O 3 on the catalytic behaviour. The reforming activity over Fe 2O3, while initially high, underwent fast deactivation. In comparison, over the Co-Fe catalyst both the H2 yield and stability were higher than that found over the pure Co3O4 or Fe 2O3 catalysts. DRIFTS-MS studies under the reaction feed highlighted that the Co-Fe catalyst had increased amounts of adsorbed OH/water; similar to Fe2O3. Increasing the amount of reactive species (water/OH species) adsorbed on the Co-Fe catalyst surface is proposed to facilitate the steam reforming reaction rather than decomposition reactions reducing by-product formation and providing a higher H2 yield. © Copyright © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

  19. A core-shell structured, metal-ceramic composite-supported Ru catalyst for methane steam reforming

    Science.gov (United States)

    Lee, Hyun Chul; Potapova, Yulia; Lee, Doohwan

    2012-10-01

    Methane steam reforming on a metal-ceramic composite-supported ruthenium catalyst is studied at high temperatures. The core-shell structured Al2O3@Al composite consisting primarily of an Al metal core with a high surface area γ-Al2O3 overlayer is obtained by hydrothermal oxidation. Under the synthesis condition, primary Al2O3@Al particles aggregate to form a hierarchal secondary structure with macrosize inter-pores. This core-shell composite support enhances the heat conductivity and provides a high surface area for fine dispersion of a catalytic Ru component on the γ-Al2O3 overlayer. The Ru/Al2O3@Al catalyst exhibits significantly higher CH4 conversion than the conventional Ru/Al2O3 catalyst, indicating its superior properties for methane steam reforming at high temperatures contributed due to the fine Ru dispersion and facilitated heat and mass transfer via the unique catalyst structure. This metal-ceramic composite catalyst is stable in the reforming reaction for an extended time, suggesting reasonable stability in its physicochemical properties.

  20. Ethanol steam reforming heated up by molten salt CSP: Reactor assessment

    NARCIS (Netherlands)

    Falco, De Marcello; Gallucci, Fausto

    2010-01-01

    In this paper hydrogen production via reforming of ethanol has been studied in a novel hybrid plant consisting in a ethanol reformer and a concentrating solar power (CSP) plant using molten salt as heat carrier fluid. The heat needed for the reforming of ethanol has been supplied to the system by mo

  1. Effectiveness factors for a commercial steam reforming (Ni) catalyst and for a calcined dolomite used downstream biomass gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Corella, J.; Narvaez, I.; Orio, A. [Madrid Univ. (Spain). Dept. of Chem. Eng.

    1996-12-31

    A commercial steam reforming catalyst from BASF, the G1-25 S one, and a calcined dolomite, Norte-1, from Cantabria-Spain, have been used, once crushed and sieved to different particle fractions between 1.0 and 4.0 mm. The materials have been tested downstream small pilot biomass gasifiers, bubbling fluidized bed type, gasifying with air and with steam. The Thiele modulus and the effectiveness factor have been calculated at temperatures of 750-850 deg C. It is experimentally shown that diffusion control plays an important part when particle size is larger than ca. 0.5 mm. This has to be taken into account when comparing the quality of the solids for tar elimination. (author) (5 refs.)

  2. Exergy analysis: An efficient tool for understanding and improving hydrogen production via the steam methane reforming process

    International Nuclear Information System (INIS)

    Exergy analysis has been shown to be an efficient tool for understanding and improvement of industrial processes. In the present study, exergy analysis has been used to examine the energy consumption of an existing Steam Methane Reforming (SMR) process and then to test for possible savings in primary energy consumption and environmental protection. In the first step, energy and exergy balances of a steam methane reforming process were established to identify the thermodynamic imperfections of the process. Recommendations from this study have contributed to the building of a new and more efficient process. Consequently, a heat exchanger, corresponding to 44.9% of the total required area for the SMR heat exchange, has been incorporated in the SMR for waste heat recovery. The thermal and exergetic efficiencies of the original process are 70% and 65.5%, respectively. For the new process, the thermal and exergetic efficiencies are 74% and 69.1%, respectively. The unused exergy is reduced by 9.3% from 125.9 to 114.2 kJ per mole of H2 produced. One mole of methane produces 2.48 mol of H2 compared to 2.35 mol of H2 produced in the original process. Furthermore, the new SMR process produces the lower greenhouse gas emissions. - Highlights: ► Exergy analysis is used for evaluating a steam methane reforming process and for guiding efficiency-improvement efforts. ► The main part of the processes exergy destroyed occurs in the chemical reactors. ► To improve the exergetic efficiency the system components should be improved and/or the exhaust exergy should be decreased. ► Heat recovery not only helps to save energy but also decreases the environmental impact.

  3. Steam reforming: an old process for a new solution; Le vaporeformage catalytique: un vieux procede pour une solution nouvelle...

    Energy Technology Data Exchange (ETDEWEB)

    Aupretre, F.; Descorme, C.; Duprez, D. [Poitiers Univ., Lab. de Catalyse en Chimie Organique, LACCO, UMR CNRS 6503, 86 (France)

    2000-07-01

    A bibliographic review allows to understand very quickly the stake that the electric-powered vehicle represents. The research of a hydrogen production process answering to the demands of the fuel cell application is then one of the main stakes. The catalytic steam reforming of hydrocarbons or of alcohols is a very promising way. The choices of ethanol and of rhodium based catalysts supported on oxides with strong oxygen mobility will be entirely justified because of the physico-chemical characteristics of the ethanol, of the reaction mechanism, of the cerium based oxide catalyst and of the specifications involved in the fuel cell application. (O.M.)

  4. Significantly Improved Catalytic Performance of Ni-Based MgO Catalyst in Steam Reforming of Phenol by Inducing Mesostructure

    OpenAIRE

    Xiaoxuan Yang; Yajing Wang; Yuhe Wang

    2015-01-01

    A Ni/meso-MgO catalyst with high surface area and small Ni nanoparticles was synthesized and investigated for hydrogen production by steam reforming of phenol for the first time. Compared to conventional Ni/MgO, the Ni/meso-MgO catalyst showed higher catalytic activity and stability. X-ray Diffraction, N2 adsorption, hydrogen temperature programmed reduction, transmission electron microscopy and thermal gravimetry results indicated that the Ni/meso-MgO catalyst had higher surface area than Ni...

  5. Thermodynamic analysis of performance of steam methane reforming hydrogen production system connected with high-temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    Thermodynamic analysis of performance of steam methane reforming hydrogen production system connected with High-Temperature Gas-Cooled Reactor is presented, which provides a framework for further detailed research. Complete reaction model and equilibrium reaction model were developed. System efficiency and hydrogen output variation related to process parameters were researched. Limit value of performance index and optimum process parameter were determined. The comparison of equilibrium reaction model prediction to experimental data shows that the equilibrium reaction model is appropriate for preliminary analysis for the system. (authors)

  6. Study on Methanol Conversion Efficiency and Mass Transfer of Steam-Methanol Reforming on Flow Rate Variation in Curved Channel

    International Nuclear Information System (INIS)

    In this study, numerical analysis of curved channel steam-methanol reformer was conducted using the computational fluid dynamics (CFD) commercial code STAR-CCM. A pre-numerical analysis of reference model with a cylindrical channel reactor was performed to validate the combustion model of the CFD commercial code. The result of advance validation was in agreement with reference model over 95%. After completing the validation, a curved channel reactor was designed to determine the effects of shape and length of flow path on methanol conversion efficiency and generation of hydrogen. Numerical analysis of the curved-channel reformer was conducted under various flow rate (10/15/20 μl/min). As a result, the characteristics of flow and mass transfer were confirmed in the cylindrical channel and curved channel reactor, and useful information about methanol conversion efficiency and hydrogen generation was obtained for various flow rate.

  7. Surface Reaction Kinetics of Steam- and CO2-Reforming as Well as Oxidation of Methane over Nickel-Based Catalysts

    Directory of Open Access Journals (Sweden)

    Karla Herrera Delgado

    2015-05-01

    Full Text Available An experimental and kinetic modeling study on the Ni-catalyzed conversion of methane under oxidative and reforming conditions is presented. The numerical model is based on a surface reaction mechanism consisting of 52 elementary-step like reactions with 14 surface and six gas-phase species. Reactions for the conversion of methane with oxygen, steam, and CO2 as well as methanation, water-gas shift reaction and carbon formation via Boudouard reaction are included. The mechanism is implemented in a one-dimensional flow field description of a fixed bed reactor. The model is evaluated by comparison of numerical simulations with data derived from isothermal experiments in a flow reactor over a powdered nickel-based catalyst using varying inlet gas compositions and operating temperatures. Furthermore, the influence of hydrogen and water as co-feed on methane dry reforming with CO2 is also investigated.

  8. Comparisons of the hydrogen-rich syngas compositions from wet rice husk slurry steam reforming reactions using different catalysts

    International Nuclear Information System (INIS)

    Rice husk slurry is pumped into a packed reactor and the products from the steam reforming reactions using different catalysts are studied. The steam/biomass weight ratio of such a system is between 3.47 and 5.25. The solids, liquid and gaseous products are a mass fraction of 2.8-4.1%, a mass fraction of 92.4-93.0% and a mass fraction of 3.5-4.7%, respectively. The hydrogen concentration in the gaseous product is approximate a volume fraction of 41% using the Al2O3 catalyst of a CuO mass fraction of 13%, a volume fraction of 38% using the Al2O3 catalyst of a Ni mass fraction of 13%, a volume fraction of 31% using the Al2O3 catalyst of a ZnO mass fraction of 13%, and a volume fraction of 20% using the Al2O3 catalyst at the reactor temperature of 800 oC. In the reactor temperature range studied (350-800 oC), the hydrogen concentration in the product stream increases monotonically with the increasing of the reactor temperature and the steam/carbon molar ratio. The value of dry gas LHV is between 9.4 MJ m-3 and 12 MJ m-3 at the reaction temperature of 600-800 oC. Considering the simple catalyst used in current study, the syngas of a hydrogen volume fraction of approximate 40% is obtained by pumping the biomass slurry to carry out the catalytic steam reforming reaction. -- Highlights: → We carry out steam reforming reaction using rice husk slurry as the feeding. → CuO/Al2O3, Ni/Al2O3, ZnO/Al2O3 and Al2O3 catalysts are used. → The syngas of a hydrogen volume fraction of approximate 40% is obtained. → Gas LHV is between 9.4 MJ m-3 and 12 MJ m-3 at reaction temperature 600-800 oC.

  9. Experimental and predicted approaches for biomass gasification with enriched air-steam in a fluidised bed.

    Science.gov (United States)

    Fu, Qirang; Huang, Yaji; Niu, Miaomiao; Yang, Gaoqiang; Shao, Zhiwei

    2014-10-01

    Thermo-chemical gasification of sawdust refuse-derived fuel was performed on a bench-scale fluidised bed gasifier with enriched air and steam as fluidising and oxidising agents. Dolomite as a natural mineral catalyst was used as bed material to reform tars and hydrocarbons. A series of experiments were carried out under typical operating conditions for gasification, as reported in the article. A modified equilibrium model, based on equilibrium constants, was developed to predict the gasification process. The sensitivity analysis of operating parameters, such as the fluidisation velocity, oxygen percentage of the enriched air and steam to biomass ratios on the produced gas composition, lower heating value, carbon conversion and cold gas efficiency was investigated. The results showed that the predicted syngas composition was in better agreement with the experimental data compared with the original equilibrium model. The higher fluidisation velocity enhanced gas-solid mixing, heat and mass transfers, and carbon fines elutriation, simultaneously. With the increase of oxygen percentage from 21% to 45%, the lower heating value of syngas increased from 5.52 MJ m(-3) to 7.75 MJ m(-3) and cold gas efficiency from 49.09% to 61.39%. The introduction of steam improved gas quality, but a higher steam to biomass ratio could decrease carbon conversion and gasification efficiency owing to a low steam temperature. The optimal value of steam to biomass ratio in this work was 1.0. PMID:25265865

  10. The hot bench scale plant Ester for the vitrification of high level wastes

    International Nuclear Information System (INIS)

    In this paper the hot bench-scale plant ESTER for the vitrification of the high-level radioactive wastes is described, and the main results of the first radioactive campaign are reported. The ESTER plant, which is placed in the ADECO-ESSOR hot cells of the C.C.R.-EURATOM-ISPRA, has been built and is operated by the ENEA, Departement of Fuel Cycle. It began operating with real radioactive wastes about 1 year ago, solidifying a total of 12 Ci of fission products into 2,02 Kg of borosilicate glass, corresponding to 757 ml of glass. During the vitrification many samples of liquid and gaseous streams have been taken and analyzed. A radioactivity balance in the plant has been calculated, as well as a mass balance of nitrates and of the 137Cs and 106Ru volatized in the process

  11. A bench scale hydrogen production test by the thermochemical water-splitting iodine-sulfur process

    International Nuclear Information System (INIS)

    The iodine-sulfur process which utilize nuclear energy has attracted a great deal of interest for economy, environmental conservation and massive production. The IS process should have unique features whereby all chemicals except hydrogen and oxygen circulate through the process. This enables continuous and closed-cycle operations. In order to achieve the operation, process control methods and its automation to maintain the process in a stable state are indispensable. A fundamental concept of the methods was developed, which was installed with automatization in a bench scaled experimental facility made of glass. To demonstrate usefulness of the method, a long-term hydrogen production test was performed. In consequence, stable hydrogen production for 1 weak was successfully accomplished. The production rate of hydrogen was 31NL/h, and the production ratio of oxygen to hydrogen agrees to 0.5:1. This result shows that the water splitting took place stably by effective performance of the control method. (author)

  12. Study on saccharification of cellulosic wastes with bench scale test plant, (2)

    International Nuclear Information System (INIS)

    The mechanical pretreatment of irradiated chaff for saccharification was studied with the bench scale test plant. Chaff was pulverized by an impact type pulverizer which could treat a large amount of cellulosic wastes in short time. The effect of pulverizing on irradiated chaff was investigated from the point of view of particle size and saccharification. From untreated chaff the low accessibility of enzyme reduces the yield of glucose. Pulverized chaff, however, gave high glucose yield resulting from the increase of the enzyme accessibility because of decrease of particle size. The fine powder of chaff rendered the possibility of the saccharification at the high slurry concentration. The radiation pretreatment with electron beam introduced the decrease of electric energy to obtain the fine powder with pulverizer. This pretreatment also increased the fine powder yield. After irradiation dose increased to more than 70 Mrad in the pretreatment, high glucose concentration was obtained only by coarse pulverizing. (author)

  13. Bench-scale testing of a micronized magnetite, fine-coal cleaning process

    Energy Technology Data Exchange (ETDEWEB)

    Suardini, P.J. [Custom Coals, International, Pittsburgh, PA (United States)

    1995-11-01

    Custom Coals, International has installed and is presently testing a 500 lb/hr. micronized-magnetite, fine-coal cleaning circuit at PETC`s Process Research Facility (PRF). The cost-shared project was awarded as part of the Coal Preparation Program`s, High Efficiency Preparation Subprogram. The project includes design, construction, testing, and decommissioning of a fully-integrated, bench-scale circuit, complete with feed coal classification to remove the minus 30 micron slimes, dense medium cycloning of the 300 by 30 micron feed coal using a nominal minus 10 micron size magnetite medium, and medium recovery using drain and rinse screens and various stages and types of magnetic separators. This paper describes the project circuit and goals, including a description of the current project status and the sources of coal and magnetite which are being tested.

  14. Final PHP bench-scale report for the DOE-ID/SAIC sole source contract

    International Nuclear Information System (INIS)

    The Plasma Hearth Process (PHP) Technology Development Project was established to develop, test, and evaluate a new concept for treating mixed waste. The new concept uses direct current (dc) transferred-arc plasma torch technology to process mixed waste into a glass-like end-product. Under the cognizance of the US Department of Energy (DOE) Office of Technology Development (OTD) Mixed Waste Focus Area (MWFA), the technology is being explored for its potential to treat mixed waste. Because it is a mature technology, well-understood and commercially available, it is expected to develop rapidly in this new application. This report summarizes the radioactive bench-scale system activities funded under PHP Sole Source Contract DE-AC07-94ID13266 through the end of the contract

  15. From a single pellet press to a bench scale pellet mill - Pelletizing six different biomass feedstocks

    DEFF Research Database (Denmark)

    Puig Arnavat, Maria; Shang, Lei; Sárossy, Zsuzsa;

    2016-01-01

    (SPP) can be extrapolated to larger scale pellet mills. The single pellet press was used to find the optimum moisture content and die operating temperature for pellet production. Then, these results were compared with those obtained from a bench-scale pellet mill. A moisture content of around 10 wt......The increasing demand for biomass pellets requires the investigation of alternative raw materials for pelletizetion. In the present paper, the pelletization process of fescue, alfalfa, sorghum, triticale, miscanthus and willow is studied to determine if results obtained in a single pellet press.......% was found to be optimal for the six biomass feedstocks. A friction increase was seen when the die temperature increased from room temperature to 60-90 degrees C for most biomass types, and then a friction decrease when the die temperature increased further. The results obtained in the bench...

  16. Bench-Scale Filtration Testing in Support of the Pretreatment Engineering Platform (PEP)

    Energy Technology Data Exchange (ETDEWEB)

    Billing, Justin M.; Daniel, Richard C.; Kurath, Dean E.; Peterson, Reid A.

    2009-09-28

    Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed, constructed and operated as part of a plan to respond to issue M12, “Undemonstrated Leaching Processes.” The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP testing program specifies that bench-scale testing is to be performed in support of specific operations, including filtration, caustic leaching, and oxidative leaching.

  17. Temperature control of bench-scaled batch reactor equipped with a monofluid heating/cooling system

    Science.gov (United States)

    Teng, Hai-peng; Song, Yi-ming

    2014-04-01

    An advanced control concept, Predictive Functional Control (PFC), is applied for temperature control of a bench-scaled batch reactor equipped with monofluid heating/cooling system. First principles process models are developed. Based on achieved models, significant process variables, which are difficult or impossible to measure online, are estimated from easily measured variables, and cascade PFC control strategy has been projected and implemented in Matlab R14. The dynamics of individual subunits is explicitly taken into consideration by internal model in the control algorithms, and model uncertainty, various process disturbances are compensated by modification of internal model. The experimental results present an excellent capability of tracking the set point, and the success of PFC technique as a process control paradigm is illustratively demonstrated.

  18. Performance evaluation of the DCMD desalination process under bench scale and large scale module operating conditions

    KAUST Repository

    Francis, Lijo

    2014-04-01

    The flux performance of different hydrophobic microporous flat sheet commercial membranes made of poly tetrafluoroethylene (PTFE) and poly propylene (PP) was tested for Red Sea water desalination using the direct contact membrane distillation (DCMD) process, under bench scale (high δT) and large scale module (low δT) operating conditions. Membranes were characterized for their surface morphology, water contact angle, thickness, porosity, pore size and pore size distribution. The DCMD process performance was optimized using a locally designed and fabricated module aiming to maximize the flux at different levels of operating parameters, mainly feed water and coolant inlet temperatures at different temperature differences across the membrane (δT). Water vapor flux of 88.8kg/m2h was obtained using a PTFE membrane at high δT (60°C). In addition, the flux performance was compared to the first generation of a new locally synthesized and fabricated membrane made of a different class of polymer under the same conditions. A total salt rejection of 99.99% and boron rejection of 99.41% were achieved under extreme operating conditions. On the other hand, a detailed water characterization revealed that low molecular weight non-ionic molecules (ppb level) were transported with the water vapor molecules through the membrane structure. The membrane which provided the highest flux was then tested under large scale module operating conditions. The average flux of the latter study (low δT) was found to be eight times lower than that of the bench scale (high δT) operating conditions.

  19. Torrefaction of pine in a bench-scale screw conveyor reactor

    International Nuclear Information System (INIS)

    Numerous works are reported in the literature regarding the torrefaction of biomass in batch processes. However, in industrial applications, continuous reactors and processes may by more interesting as this allows for the integration of continuous mass and heat flows. To shed light on the operation of continuous torrefaction processes, this work presents the findings of continuous, bench-scale (2.5 kg h−1) torrefaction experiments using pine wood particles as a feed material in a screw conveyor reactor. The shifts in product mass yields were in line with theoretical expectations for changes in reactor temperature and reactor residence times whereas the degree of filling within the screw reactor and the flow of the nitrogen purge gas were found to be negligible. The process allowed for the measurement of the particle surface temperatures throughout the length of the reactor and significant temperature differences where measured between the wall of the reactor and the reactor screw. The proximate composition and the higher heating value of the torrefied biomass were found to be correlated to the ratio of the mass of dry biomass feed to the mass of the torrefied biomass produced. Important observations regarding the operability of such a process, also relevant to larger-scale processes, include the need to prevent the occurrence of torrefaction vapour condensation (which leaves the torrefaction reactor in the form of a saturated vapour) in the presence of fine, solid particles as this leads to rapid particle agglomeration and process blockage. - Highlights: • Successful, continuous torrefaction of pine at bench-scale (2.5 kg h−1). • Internal reactor temperatures were significantly lower than reactor wall temperatures in all cases. • Agglomeration of fine particles with condensed vapours, and the occurrence of feed variability were encountered. • Proximate composition and HHV of torrefied biomass can be predicted by linear correlation against inverse of

  20. Bench-scale screening tests for a boiling sodium-potassium alloy solar receiver

    Science.gov (United States)

    Moreno, J. B.; Moss, T. A.

    1993-06-01

    Bench-scale tests were carried out in support of the design of a second-generation 75-kW(sub t) reflux pool-boiler solar receiver. The receiver will be made from Haynes Alloy 230 and will contain the sodium-potassium alloy NaK-78. The bench-scale tests used quartz lamp heated boilers to screen candidate boiling stabilization materials and methods at temperatures up to 750 degree C. Candidates that provided stable boiling were tested for hot-restart behavior. Poor stability was obtained with single 1/4-inch diameter patches of powdered metal hot press sintered onto the wetted side of the heat-input area. Laser-drilled and electric discharge machined cavities in the heated surface also performed poorly. Small additions of xenon, and heated-surface tilt out of the vertical, dramatically improved poor boiling stability; additions of helium or oxygen did not. The most stable boiling was obtained when the entire heat-input area was covered by a powdered-metal coating. The effect of heated-area size was assessed for one coating: at low incident fluxes, when even this coating performed poorly, increasing the heated-area size markedly improved boiling stability. Good hot-restart behavior was not observed with any candidate, although results were significantly better with added xenon in a boiler shortened from 3 to 2 feet. In addition to the screening tests, flash-radiography imaging of metal-vapor bubbles during boiling was attempted. Contrary to the Cole-Rohsenow correlation, these bubble-size estimates did not vary with pressure; instead they were constant, consistent with the only other alkali metal measurements, but about 1/2 their size.

  1. Preparation and initial characterization of fluidized bed steam reforming pure-phase standards

    Energy Technology Data Exchange (ETDEWEB)

    Missimer, D. M.; Rutherford, R. L.

    2013-03-21

    Hanford is investigating the Fluidized Bed Steam Reforming (FBSR) process for their Low Activity Waste. The FBSR process offers a low-temperature continuous method by which liquid waste can be processed with the addition of clay into a sodium aluminosilicate (NAS) waste form. The NAS waste form is mainly comprised of nepheline (NaAlSiO{sub 4}), sodalite (Na{sub 8}[AlSiO{sub 4}]{sub 6}Cl{sub 2}), and nosean (Na{sub 8}[AlSiO{sub 4}]{sub 6}SO{sub 4}). Anions such as perrhenate (ReO{sub 4}{sup -}), pertechnetate (TcO{sub 4}{sup -}), and iodine (I{sup -}) are expected to replace sulfate in the nosean structure and/or chloride in the sodalite mineral structure (atomically bonded inside the aluminosilicate cages that these mineral structures possess). In the FBSR waste form, each of these phases can exist in a variety of solid solutions that differ from the idealized forms observed in single crystals in nature. The lack of understanding of the durability of these stoichiometric or idealized mineral phases complicates the ability to deconvolute the durability of the mixed phase FBSR product since it is a combination of different NAS phases. To better understand the behavior, fabrication and testing of the individual phases of the FBSR product is required. Analytical Development (AD) of the Science and Technology directorate of the Savannah River National Laboratory (SRNL) was requested to prepare the series of phase-pure standards, consisting of nepheline, nosean, and Cl, Re, and I sodalite. Once prepared, X-ray Diffraction (XRD) analyses were used to confirm the products were phase pure. These standards are being used for subsequent characterization studies consisting of the following: single-pass flow-through (SPFT) testing, development of thermodynamic data, and x-ray diffraction (XRD) calibration curves. In addition to the above mentioned phase-pure standards, AD was tasked with fabricating a mixed Tc-Re sodalite.

  2. MECHANISTIC KINETIC MODELS FOR STEAM REFORMING OF CONCENTRATED CRUDE ETHANOL ON NI/AL2O3 CATALYST

    Directory of Open Access Journals (Sweden)

    O. A. OLAFADEHAN

    2015-05-01

    Full Text Available Mechanistic kinetic models were postulated for the catalytic steam reforming of concentrated crude ethanol on a Ni-based commercial catalyst at atmosphere pressure in the temperature range of 673-863 K, and at different catalyst weight to the crude ethanol molar flow rate ratio (in the range 0.9645-9.6451 kg catalyst h/kg mole crude ethanol in a stainless steel packed bed tubular microreactor. The models were based on Langmuir-Hinshelwood-Hougen-Watson (LHHW and Eley-Rideal (ER mechanisms. The optimization routine of Nelder-Mead simplex algorithm was used to estimate the inherent kinetic parameters in the proposed models. The selection of the best kinetic model amongst the rival kinetic models was based on physicochemical, statistical and thermodynamic scrutinies. The rate determining step for the steam reforming of concentrated crude ethanol on Ni/Al2O3 catalyst was found to be surface reaction between chemisorbed CH3O and O when hydrogen and oxygen were adsorbed as monomolecular species on the catalyst surface. Excellent agreement was obtained between the experimental rate of reaction and conversion of crude ethanol, and the simulated results, with ADD% being ±0.46.

  3. Steam Reforming Technology Demonstration Program for Treatment of DOE Sodium Bearing Tank Wastes at Idaho National Laboratory

    International Nuclear Information System (INIS)

    The patented THORR steam reforming waste treatment technology has been selected by the Department of Energy (DOE) for treatment of Sodium Bearing Waste (SBW) at the Idaho National Laboratory (INL). SBW is an acidic waste created primarily from cleanup of the fuel reprocessing equipment at the Idaho Nuclear Technology and Engineering Center (INTEC) at the INL. The SBW contains high concentrations of nitric acid and alkali and aluminum nitrates, along with many other inorganic compounds, including substantial levels of radionuclides. As part of the implementation of the THORR process at INTEC, an engineering-scale test demonstration (ESTD) was conducted using a specially designed pilot plant located at Hazen Research, Inc. in Golden Colorado. The purpose of the ESTD was to confirm and optimize operation of the THORR dual fluidized bed steam reforming (FBSR) process for treating the SBW. The performance of the integrated FBSR thermal and off-gas systems was demonstrated while treating waste simulants representative of the actual SBW. Simulants were utilized that consisted of highly acidic nitrate solutions, with both dissolved and undissolved solids (UDS). The SBW simulant solutions were converted into a dry, granular solid, consisting of carbonate and aluminate product compounds. The successful performance of the integrated FBSR system was verified and demonstrated. (authors)

  4. Steam Reforming Application for Treatment of DOE Sodium Bearing Tank Wastes at Idaho National Laboratory for Idaho Cleanup Project

    International Nuclear Information System (INIS)

    The patented THORR steam reforming waste treatment technology has been selected as the technology of choice for treatment of Sodium Bearing Waste (SBW) at the Idaho National Laboratory (INL) for the Idaho Cleanup Project (ICP). SBW is an acidic tank waste at the Idaho Nuclear Technology and Engineering Center (INTEC) at INL. It consists primarily of waste from decontamination activities and laboratory wastes. SBW contains high concentrations of nitric acid, alkali and aluminum nitrates, with minor amounts of many inorganic compounds including radionuclides, mainly cesium and strontium. The THORR steam reforming process will convert the SBW tank waste feed into a dry, solid, granular product. The THORR technology was selected to treat SBW, in part, because it can provide flexible disposal options to accommodate the final disposition path selected for SBW. THORR can produce a final end-product that will meet anticipated requirements for disposal as Remote-Handled TRU (RH-TRU) waste; and, with modifications, THORR can also produce a final end-product that could be qualified for disposal as High Level Waste (HLW). SBW treatment will be take place within the Integrated Waste Treatment Unit (IWTU), a new facility that will be located at the INTEC. This paper provides an overview of the THORR process chemistry and process equipment being designed for the IWTU. (authors)

  5. Hydrogen production from raw bioethanol steam reforming : optimization of catalyst composition with improved stability against various impurities

    Energy Technology Data Exchange (ETDEWEB)

    Le Valant, A.; Can, F.; Bion, N.; Epron, F.; Duprez, D. [Poitiers Univ., Poitiers (France). Laboratoire de Catalyse en Chimie organique

    2009-07-01

    This study investigated the effects of raw ethanol impurities on catalytic performance during ethanol steam reforming processes. An Rh/MgAI{sub 2}O{sub 4} reference catalyst was used. Steam reforming was conducted in a fixed bed reactor. The study showed that aldehyde, amine, and methanol have no negative impacts on catalytic performance. Deactivation is caused by coke formation as a result of the presence of the impurities in the feed. The composition of the support and metallic phases of the catalyst formulation were then modified in order to improve the stability of the catalyst in the presence of deactivating impurities. Rare earth elements were used to replace magnesium and decrease strong and medium acid sites. Ethanol conversion and hydrogen yield were both increased when the dehydration reaction was disfavoured. The metallic phase was modified by the addition of a second metal. It was concluded that the Rh-NiY-Al{sub 2}O{sub 3} catalyst has the highest hydrogen yield, and is more stable than the reference catalyst. 16 refs., 7 figs.

  6. Modeling the kinetics of methane conversion in steam reforming process of coke-oven gas based on experimental data

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jia-yuan; ZHOU Jie-min

    2007-01-01

    Steam-reforming is an effective approach for upgrading methane and hydrocarbon of coke-oven gas into CO and H2, but the kinetic behavior needs more study. We investigated the conversion of methane in coke-oven gas by steam reforming process in an electric tubular flow at 14 kPa with temperature varying from 500℃ to 950℃, and developed a kenetic model for , ignoring the effects of adsorption and diffusion. The optimal dynamic conditions for methane conversion 14 kPa are as follows: the ratio of the amount of water to the amount of methane is from 1.1 to 1.3; the reaction temperature is from 1 223 K to 1 273 K. The methane conversion rate is larger than 95% when the ratio of the amount of water to the amount of methane is 1.2 at a temperature above 1 223 K with the residence time up to 0.75 s.

  7. Minimizing the formation of coke and methane on Co nanoparticles in steam reforming of biomass-derived oxygenates

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Junming; Mei, Donghai; Karim, Ayman M.; Datye, Abhaya K.; Wang, Yong

    2013-06-01

    Fundamental understanding and control of chemical transformations are essential to the development of technically feasible and economically viable catalytic processes for efficient conversion of biomass to fuels and chemicals. Using an integrated experimental and theoretical approach, we report high hydrogen selectivity and catalyst durability of acetone steam reforming (ASR) on inert carbon supported Co nanoparticles. The observed catalytic performance is further elucidated on the basis of comprehensive first-principles calculations. Instead of being considered as an undesired intermediate prone for catalyst deactivation during bioethanol steam reforming (ESR), acetone is suggested as a key and desired intermediate in proposed two-stage ESR process that leads to high hydrogen selectivity and low methane formation on Co-based catalysts. The significance of the present work also sheds a light on controlling the chemical transformations of key intermediates in biomass conversion such as ketones. We gratefully acknowledge the financial support from U. S. Department of Energy (DOE), Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences, and the Laboratory directed research and development (LDRD) project of Pacific Northwest National Laboratory (PNNL). Computing time was granted by the William R. Wiley Environmental Molecular Sciences Laboratory (EMSL). The EMSL is a U.S. DOE national scientific user facility located at PNNL, and sponsored by the U.S. DOE’s Office of Biological and Environmental Research.

  8. Significantly Improved Catalytic Performance of Ni-Based MgO Catalyst in Steam Reforming of Phenol by Inducing Mesostructure

    Directory of Open Access Journals (Sweden)

    Xiaoxuan Yang

    2015-10-01

    Full Text Available A Ni/meso-MgO catalyst with high surface area and small Ni nanoparticles was synthesized and investigated for hydrogen production by steam reforming of phenol for the first time. Compared to conventional Ni/MgO, the Ni/meso-MgO catalyst showed higher catalytic activity and stability. X-ray Diffraction, N2 adsorption, hydrogen temperature programmed reduction, transmission electron microscopy and thermal gravimetry results indicated that the Ni/meso-MgO catalyst had higher surface area than Ni/MgO and Ni particles of Ni/meso-MgO were narrowly distributed in the range of 5~6 nm with an average size of 5.3 nm, while Ni particles of Ni/MgO were in the range of 6~10 nm with an average size of 7.92 nm. The small and uniform Ni nanoparticles in Ni/meso-MgO were attributed to the high surface area and the confinement effect of the mesoporous structure of meso-MgO, which could effectively limit the growth of the active metal and stabilize Ni particles during the procedure of NiO reduction. The mesoporous structure of Ni/meso-MgO also played an important role in suppressing Ni nanoparticle sintering and carbon deposition during the steam reforming of phenol reaction.

  9. Polymer electrolyte membrane fuel cell grade hydrogen production by methanol steam reforming: A comparative multiple reactor modeling study

    Science.gov (United States)

    Katiyar, Nisha; Kumar, Shashi; Kumar, Surendra

    2013-12-01

    Analysis of a fuel processor based on methanol steam reforming has been carried out to produce fuel cell grade H2. Six reactor configurations namely FBR1 (fixed bed reactor), MR1 (H2 selective membrane reactor with one reaction tube), MR2 (H2 selective membrane reactor with two reaction tubes), FBR2 (FBR1 + preferential CO oxidation (PROX) reactor), MR3 (MR1 + PROX), and MR4 (MR2 + PROX) are evaluated by simulation to identify the suitable processing scheme. The yield of H2 is significantly affected by H2 selective membrane, residence time, temperature, and pressure conditions at complete methanol conversion. The enhancement in residence time in MR2 by using two identical reaction tubes provides H2 yield of 2.96 with 91.25 mol% recovery at steam/methanol ratio of 1.5, pressure of 2 bar and 560 K temperature. The exit retentate gases from MR2 are further treated in PROX reactor of MR4 to reduce CO concentration to 4.1 ppm to ensure the safe discharge to the environment. The risk of carbon deposition on reforming catalyst is highly reduced in MR4, and MR4 reactor configuration generates 7.4 NL min-1 of CO free H2 from 0.12 mol min-1 of methanol which can provide 470 W PEMFC feedstock requirement. Hence, process scheme in MR4 provides a compact and innovative fuel cell grade H2 generating unit.

  10. Synthesis and Activity Test of Cu/ZnO/Al2O3 for the Methanol Steam Reforming as a Fuel Cell’s Hydrogen Supplier

    OpenAIRE

    IGBN Makertihartha; Subagjo; Melia Laniwati Gunawan

    2009-01-01

    The synthesis of hydrogen from hydrocarbons through the steam reforming of methanol on Cu/ZnO/Al2O3 catalyst has been investigated. This process is assigned to be one of the promising alternatives for fuel cell hydrogen process source. Hydrogen synthesis from methanol can be carried out by means of methanol steam reforming which is a gas phase catalytic reaction between methanol and water. In this research, the Cu/ZnO/Al2O3 catalyst prepared by the dry impregnation was used. The specific surf...

  11. A bimodal catalytic membrane having a hydrogen-permselective silica layer on a bimodal catalytic support: Preparation and application to the steam reforming of methane

    OpenAIRE

    Tsuru, Toshinori; Shintani, Hiroaki; Yoshioka, Tomohisa; Asaeda, Masashi

    2006-01-01

    The steam reforming of methane for hydrogen production was experimentally investigated using catalytic membrane reactors, consisting of a microporous silica top layer, for the selective permeation of hydrogen, and an α-alumina support layer, for catalytic reaction of the steam reforming of methane. An α-alumina support layer with a bimodal structure, which was proposed for the enhanced dispersion of Ni catalysts, was prepared by impregnating γ-Al2O3 inside α-Al2O3 microfiltration membranes (1...

  12. Feasibility of the direct generation of hydrogen for fuel-cell-powered vehicles by on-board steam reforming of naphtha

    OpenAIRE

    Darwish, Naif A.; Hilal, Nidal; Versteeg, Geert; Heesink, Bert

    2004-01-01

    A process flow sheet for the production of hydrogen to run a 50 kW fuel-cell-powered-vehicle by steam reforming of naphtha is presented. The major units in the flow sheet involve a desulfurization unit, a steam reformer, a low temperature (LT) shift reactor, a methanation reactor, and a membrane separator unit. The flow sheet is simulated using HYSYS (a steady state simulator) and the material and energy flows for each stream are obtained. For the peak load of 50 kW, it is found that 14 l/h n...

  13. Development of methane conversion improvement method by recycling of residual methane for steam reforming as a part of R and D of HTGR-hydrogen production system

    International Nuclear Information System (INIS)

    The purpose of the present study is to improve methane conversion for an HTGR-steam reforming system by recycling of residual methane. The residual methane in a product gas after steam reforming was recycled with a gas separator of polyimide membrane. Gas separation characteristics of the separator were investigated experimentally and numerically, and an experimental study on recycling system was carried out. The results showed that the recycling system improves apparent methane conversion, ratio of methane conversion to methane supply from a cylinder, from 20 to 32% compared with those without recycling. (author)

  14. Numerical simulation of effect of catalyst wire-mesh pressure drop characteristics on flow distribution in catalytic parallel plate steam reformer

    DEFF Research Database (Denmark)

    Sigurdsson, Haftor Örn; Kær, Søren Knudsen

    2012-01-01

    Steam reforming of hydrocarbons using a catalytic plate-type-heat-exchanger (CPHE) reformer is an attractive method of producing hydrogen for a fuel cell-based micro combined-heat-and-power system. In this study the flow distribution in a CPHE reformer, which uses a coated wire-mesh catalyst, is...... with momentum source to account for the pressure drop. The numerical model is verified experimentally, numerical and experimental results are found to be in good agreement. The study shows that severe flow maldistribution exists in the current reformer stack. At nominal load some channels in the CPHE...... coefficients and at five different flow rates. Experiments are performed on a single CPHE reformer channel to evaluate the pressure drop characteristics of the catalyst wire-mesh in the current CPHE reformer design. The results are used in the numerical model where the catalyst zone is simulated as domains...

  15. Numerical study of methanol–steam reforming and methanol–air catalytic combustion in annulus reactors for hydrogen production

    International Nuclear Information System (INIS)

    Highlights: ► Performance of mini-scale integrated annulus reactors for hydrogen production. ► Flow rates fed to combustor and reformer control the reactor performance. ► Optimum performance is found from balance of flow rates to combustor and reformer. ► Better performance can be found when shell side is designed as combustor. -- Abstract: This study presents the numerical simulation on the performance of mini-scale reactors for hydrogen production coupled with liquid methanol/water vaporizer, methanol/steam reformer, and methanol/air catalytic combustor. These reactors are designed similar to tube-and-shell heat exchangers. The combustor for heat supply is arranged as the tube or shell side. Based on the obtained results, the methanol/air flow rate through the combustor (in terms of gas hourly space velocity of combustor, GHSV-C) and the methanol/water feed rate to the reformer (in terms of gas hourly space velocity of reformer, GHSV-R) control the reactor performance. With higher GHSV-C and lower GHSV-R, higher methanol conversion can be achieved because of higher reaction temperature. However, hydrogen yield is reduced and the carbon monoxide concentration is increased due to the reversed water gas shift reaction. Optimum reactor performance is found using the balance between GHSV-C and GHSV-R. Because of more effective heat transfer characteristics in the vaporizer, it is found that the reactor with combustor arranged as the shell side has better performance compared with the reactor design having the combustor as the tube side under the same operating conditions.

  16. Optimization of H2 production with CO2 capture by steam reforming of methane integrated with a chemical-looping combustion system

    OpenAIRE

    Pans Castillo, Miguel Ángel; Abad Secades, Alberto; Diego Poza, Luis F. de; García Labiano, Francisco; Gayán Sanz, Pilar; Adánez Elorza, Juan

    2013-01-01

    Methane steam reforming (SR) integrated with a chemical-looping combustion (CLC) system is a new process for producing hydrogen from natural gas, allowing carbon dioxide capture with a low energy penalty. In this study, mass and enthalpy balances of an SR-CLC system were carried out to determine the autothermal operating conditions for optimal H2 production. The evaluation was conducted using iron-based oxygen carriers. Two configurations were analysed, firstly with the reformer tubes inside ...

  17. Hydrogen generation having CO2 removal with steam reforming

    Energy Technology Data Exchange (ETDEWEB)

    Kandaswamy, Duraiswamy; Chellappa, Anand S.; Knobbe, Mack

    2015-07-28

    A method for producing hydrogen using fuel cell off gases, the method feeding hydrocarbon fuel to a sulfur adsorbent to produce a desulfurized fuel and a spent sulfur adsorbent; feeding said desulfurized fuel and water to an adsorption enhanced reformer that comprises of a plurality of reforming chambers or compartments; reforming said desulfurized fuel in the presence of a one or more of a reforming catalyst and one or more of a CO2 adsorbent to produce hydrogen and a spent CO2 adsorbent; feeding said hydrogen to the anode side of the fuel cell; regenerating said spent CO2 adsorbents using the fuel cell cathode off-gases, producing a flow of hydrogen by cycling between said plurality of reforming chambers or compartments in a predetermined timing sequence; and, replacing the spent sulfur adsorbent with a fresh sulfur adsorbent at a predetermined time.

  18. Hydrogen-Rich Gas Production by Sorption Enhanced Steam Reforming of Woodgas Containing TAR over a Commercial Ni Catalyst and Calcined Dolomite as CO2 Sorbent

    OpenAIRE

    Vincenzo Naso; Andrea Micangeli; Mario Sisinni; Enrico Bocci; Andrea Di Carlo

    2013-01-01

    The aim of this work was the evaluation of the catalytic steam reforming of a gaseous fuel obtained by steam biomass gasification to convert topping atmosphere residue (TAR) and CH4 and to produce pure H2 by means of a CO2 sorbent. This experimental work deals with the demonstration of the practical feasibility of such concepts, using a real woodgas obtained from fluidized bed steam gasification of hazelnut shells. This study evaluates the use of a commercial Ni catalyst and calcined dolomite...

  19. Hydrogen-Rich Gas Production by Sorption Enhanced Steam Reforming of Woodgas Containing TAR over a Commercial Ni Catalyst and Calcined Dolomite as CO 2 Sorbent

    OpenAIRE

    Mario Sisinni; Andrea Di Carlo; Enrico Bocci; Andrea Micangeli; Vincenzo Naso

    2013-01-01

    The aim of this work was the evaluation of the catalytic steam reforming of a gaseous fuel obtained by steam biomass gasification to convert topping atmosphere residue (TAR) and CH 4 and to produce pure H 2 by means of a CO 2 sorbent. This experimental work deals with the demonstration of the practical feasibility of such concepts, using a real woodgas obtained from fluidized bed steam gasification of hazelnut shells. This study evaluates the use of a commercial Ni catalyst and calcined dolom...

  20. Hydrogen production by steam reforming of bio-alcohols. The use of conventional and membrane-assisted catalytic reactors

    Energy Technology Data Exchange (ETDEWEB)

    Seelam, P. K.

    2013-11-01

    The energy consumption around the globe is on the rise due to the exponential population growth and urbanization. There is a need for alternative and non-conventional energy sources, which are CO{sub 2}-neutral, and a need to produce less or no environmental pollutants and to have high energy efficiency. One of the alternative approaches is hydrogen economy with the fuel cell (FC) technology which is forecasted to lead to a sustainable society. Hydrogen (H{sub 2}) is recognized as a potential fuel and clean energy carrier being at the same time a carbon-free element. Moreover, H{sub 2} is utilized in many processes in chemical, food, metallurgical, and pharmaceutical industry and it is also a valuable chemical in many reactions (e.g. refineries). Non-renewable resources have been the major feedstock for H{sub 2} production for many years. At present, {approx}50% of H{sub 2} is produced via catalytic steam reforming of natural gas followed by various down-stream purification steps to produce {approx}99.99% H{sub 2}, the process being highly energy intensive. Henceforth, bio-fuels like biomass derived alcohols (e.g. bio-ethanol and bio-glycerol), can be viable raw materials for the H{sub 2} production. In a membrane based reactor, the reaction and selective separation of H{sub 2} occur simultaneously in one unit, thus improving the overall reactor efficiency. The main motivation of this work is to produce H{sub 2} more efficiently and in an environmentally friendly way from bio-alcohols with a high H{sub 2} selectivity, purity and yield. In this thesis, the work was divided into two research areas, the first being the catalytic studies using metal decorated carbon nanotube (CNT) based catalysts in steam reforming of ethanol (SRE) at low temperatures (<450 deg C). The second part was the study of steam reforming (SR) and the water-gas-shift (WGS) reactions in a membrane reactor (MR) using dense and composite Pd-based membranes to produce high purity H{sub 2}. CNTs

  1. The application of inelastic neutron scattering to investigate the steam reforming of methane over an alumina-supported nickel catalyst

    International Nuclear Information System (INIS)

    Highlights: • Inelastic neutron scattering has been used to investigate a Ni/alumina catalyst. • The extent of hydrogen retention by the catalyst has been determined. • Filamentous carbon is identified as a by-product. - Abstract: An alumina-supported nickel catalyst, previously used in methane reforming experiments employing CO2 as the oxidant, is applied here in the steam reforming variant of the process. Micro-reactor experiments are used to discern an operational window compatible with sample cells designed for inelastic neutron scattering (INS) experiments. INS spectra are recorded after 6 h reaction of a 1:1 mixture of CH4 and H2O at 898 K. Weak INS spectra are observed, indicating minimal hydrogen retention by the catalyst in this operational regime. Post-reaction, the catalyst is further characterised by powder X-ray diffraction, transmission electron microscopy and Raman scattering. In a comparable fashion to that seen for the ‘dry’ reforming experiments, the catalyst retains substantial quantities of carbon in the form of filamentous coke. The role for hydrogen incorporation by the catalyst is briefly considered

  2. The application of inelastic neutron scattering to investigate the steam reforming of methane over an alumina-supported nickel catalyst

    Energy Technology Data Exchange (ETDEWEB)

    McFarlane, Andrew R.; Silverwood, Ian P. [School of Chemistry, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Norris, Elizabeth L.; Ormerod, R. Mark [Department of Chemistry, School of Physical and Geographical Sciences, Keele University, Staffs ST5 5BG (United Kingdom); Frost, Christopher D.; Parker, Stewart F. [ISIS Facility, STFC Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX (United Kingdom); Lennon, David, E-mail: David.Lennon@glasgow.ac.uk [School of Chemistry, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ (United Kingdom)

    2013-12-12

    Highlights: • Inelastic neutron scattering has been used to investigate a Ni/alumina catalyst. • The extent of hydrogen retention by the catalyst has been determined. • Filamentous carbon is identified as a by-product. - Abstract: An alumina-supported nickel catalyst, previously used in methane reforming experiments employing CO{sub 2} as the oxidant, is applied here in the steam reforming variant of the process. Micro-reactor experiments are used to discern an operational window compatible with sample cells designed for inelastic neutron scattering (INS) experiments. INS spectra are recorded after 6 h reaction of a 1:1 mixture of CH{sub 4} and H{sub 2}O at 898 K. Weak INS spectra are observed, indicating minimal hydrogen retention by the catalyst in this operational regime. Post-reaction, the catalyst is further characterised by powder X-ray diffraction, transmission electron microscopy and Raman scattering. In a comparable fashion to that seen for the ‘dry’ reforming experiments, the catalyst retains substantial quantities of carbon in the form of filamentous coke. The role for hydrogen incorporation by the catalyst is briefly considered.

  3. Development and application of a two-dimensional computer code for the investigation of the transient behaviour of a steam reformer with segmental baffles

    International Nuclear Information System (INIS)

    This study deals with the theoretical description of heat transport and flow distribution in a helium-heated steam reformer with segmental baffles. For this purpose a two-dimensional, transient computer code is developed, which is described in detail. A first application of this code is demonstrated by designing an 8.25 MW steam reformer for the planned AVR-process heat plant. In a parameter study the sensitivity of such a heat exchanger to the variation of some constructional features is demonstrated and the above mentioned 8.25 MW steam reformer is optimized by the aid of the so gained knowledge. Finally the transient behaviour of the hot gas duct and the steam reformer of the AVR-process heat plant during start up is investigated. It is shown, that, from the technical point of view, it will be possible to start operating the process heat loop with a helium temperature above 600degC while keeping within safety requirements. (orig.)

  4. Treatment studies of plutonium-bearing INEEL waste surrogates in a bench-scale arc furnace

    International Nuclear Information System (INIS)

    Since 1989, the Subsurface Disposal Area (SDA) at the Idaho National Environmental and Engineering Laboratory (INEEL) has been included on the National Priority List for remediation. Arc- and plasma-heated furnaces are being considered for converting the radioactive mixed waste buried in the SDA to a stabilized-vitreous form. Nonradioactive, surrogate SDA wastes have been melted during tests in these types of furnaces, but data are needed on the behavior of transuranic (TRU) constituents, primarily plutonium, during thermal treatment. To begin collecting this data, plutonium-spiked SDA surrogates were processed in a bench-scale arc furnace to quantify the fate of the plutonium and other hazardous and nonhazardous metals. Test conditions included elevating the organic, lead, chloride, and sodium contents of the surrogates. Blends having higher organic contents caused furnace power levels to fluctuate. An organic content corresponding to 50% INEEL soil in a soil-waste blend was the highest achievable before power fluctuations made operating conditions unacceptable. The glass, metal, and off-gas solids produced from each surrogate blend tested were analyzed for elemental (including plutonium) content and the partitioning of each element to the corresponding phase was calculated

  5. Dissolved gas exsolution to enhance gas production and transport during bench-scale electrical resistance heating

    Science.gov (United States)

    Hegele, P. R.; Mumford, K. G.

    2015-05-01

    Condensation of volatile organic compounds in colder zones can be detrimental to the performance of an in situ thermal treatment application for the remediation of chlorinated solvent source zones. A novel method to increase gas production and limit convective heat loss in more permeable, potentially colder, zones involves the injection and liberation of dissolved gas from solution during heating. Bench-scale electrical resistance heating experiments were performed with a dissolved carbon dioxide and sodium chloride solution to investigate exsolved gas saturations and transport regimes at elevated, but sub-boiling, temperatures. At sub-boiling temperatures, maximum exsolved gas saturations of Sg = 0.12 were attained, and could be sustained when the carbon dioxide solution was injected during heating rather than emplaced prior to heating. This gas saturation was estimated to decrease groundwater relative permeability to krw = 0.64. Discontinuous gas transport was observed above saturations of Sg = 0.07, demonstrating the potential of exsolved CO2 to bridge vertical gas transport through colder zones.

  6. A bench scale study of a one-step dissolution process for treating contaminated fiberglass filters

    International Nuclear Information System (INIS)

    High efficiency mist eliminators (HEME) and high efficiency particulate air filters (HEPA) made of High fiberglass will be used at the Savannah River Site (SRS) to remove particulate matter from offgases generated during melter feed preparation and vitrification of high-level radioactive waste (HLW) at the Defense Waste Processing Facility (DWPF). These filters will be contaminated with high-level, radioactive species and also with various high-boiling organic compounds. For this reason, a process was developed at the Savannah River Technology Center (SRTC) that will dissolve the spent filters so that the residues may be recycled to the HLW tanks for eventual vitrification. This process involves boiling the filters sequentially in NaOH, HN03 and NaOH, while contained in a stainless steal wire mesh frame assembly. The objective of this communication is to present some of the original preliminary work done by Ritter on the simple one-step dissolution process. The results from six bench-scale experiments are reported for the dissolution of an organically-fouled sample of HEME obtained from the Integrated DWPF Melter (IDMS) offgas filtration system. The preliminary effects of filter packing density, air sparging versus rotating basket agitation, fouling, and adding Triton X-405 as a dispersing agent are reported

  7. Continuous bench-scale slurry catalyst testing direct coal liquefaction rawhide sub-bituminous coal

    Energy Technology Data Exchange (ETDEWEB)

    Bauman, R.F.; Coless, L.A.; Davis, S.M. [and others

    1995-12-31

    In 1992, the Department of Energy (DOE) sponsored research to demonstrate a dispersed catalyst system using a combination of molybdenum and iron precursors for direct coal liquefaction. This dispersed catalyst system was successfully demonstrated using Black Thunder sub-bituminous coal at Wilsonville, Alabama by Southern Electric International, Inc. The DOE sponsored research continues at Exxon Research and Development Laboratories (ERDL). A six month continuous bench-scale program using ERDL`s Recycle Coal Liquefaction Unit (RCLU) is planned, three months in 1994 and three months in 1995. The initial conditions in RCLU reflect experience gained from the Wilsonville facility in their Test Run 263. Rawhide sub-bituminous coal which is similar to the Black Thunder coal tested at Wilsonville was used as the feed coal. A slate of five dispersed catalysts for direct coal liquefaction of Rawhide sub-bituminous coal has been tested. Throughout the experiments, the molybdenum addition rate was held constant at 100 wppm while the iron oxide addition rate was varied from 0.25 to 1.0 weight percent (dry coal basis). This report covers the 1994 operations and accomplishments.

  8. Destruction of methylphosphonic acid in a supercritical water oxidation bench-scale double wall reactor

    Institute of Scientific and Technical Information of China (English)

    Bambang Veriansyah; Eun-Seok Song; Jae-Duck Kim

    2011-01-01

    The destruction of methylphosphonic acid (MPA), a final product by hydrolysis/neutralization of organophosphorus agents such as satin and VX (O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothionate), was investigated in a a bench-scale, continuous concentric vertical double wall reactor under supercritical water oxidation condition. The experiments were conducted at a temperature range of 450-600~C and a fixed pressure of 25 MPa. Hydrogen peroxide was used as an oxidant. The destruction efficiency (DE) was monitored by analyzing total organic carbon (TOC) and MPA concentrations using ion chromatography on the liquid effluent samples. The results showed that the DE of MPA up to 99.999% was achieved at a reaction temperature of 600~C, oxygen concentration of 113% storichiometric requirement, and reactor residence time of 8 sec. On the basis of the data derived from experiments, a global kinetic rate equation for the DE of MPA and DE of TOC were developed by nonlinear regression analysis. The model predictions agreed well with the experimental data.

  9. Study on hydrogen sulfide removal based on bench-scale experiment by bio-trickling filter

    Institute of Scientific and Technical Information of China (English)

    TIAN Shu-lei; ZHANG Lan-he; WANG Qun-hui; WANG Xu-ming; XIE Wei-min

    2007-01-01

    A bench-scale experiment for control of hydrogen sulfide (H2S) emissions was carried out continuously for nearly four months by using bio-trickling filter packed with ZX01 stuffing. The results suggested that the bio-trickling filter had proven excellent performance over substantial operational periods. Removal efficiency of H2S was nearly 100% when volumetric loading of the bio-trickling filter varied from 0.64 g/(m3·h)to 38.20 g/(m3·h) and metabolism products of H2S were mainly composed of SO42-. When inlet concentration of H2S was 250 mg/m3, the optimum gas retention time was 30 s and the optimum spray water not blocked during experiments for nearly four months during which resistance was maintained at relatively lower value, so that the bio-trickling filter need not carry out back washing frequently and can be operated steadily for long-term.

  10. 100 Area soil washing: Bench scale tests on 116-F-4 pluto crib soil

    Energy Technology Data Exchange (ETDEWEB)

    Field, J.G.

    1994-06-10

    The Pacific Northwest Laboratory conducted a bench-scale treatability study on a pluto crib soil sample from 100 Area of the Hanford Site. The objective of this study was to evaluate the use of physical separation (wet sieving), treatment processes (attrition scrubbing, and autogenous surface grinding), and chemical extraction methods as a means of separating radioactively-contaminated soil fractions from uncontaminated soil fractions. The soil washing treatability study was conducted on a soil sample from the 116-F-4 Pluto Crib that had been dug up as part of an excavation treatability study. Trace element analyses of this soil showed no elevated concentrations above typically uncontaminated soil background levels. Data on the distribution of radionuclide in various size fractions indicated that the soil-washing tests should be focused on the gravel and sand fractions of the 116-F-4 soil. The radionuclide data also showed that {sup 137}Cs was the only contaminant in this soil that exceeded the test performance goal (TPG). Therefore, the effectiveness of subsequent soil-washing tests for 116-F-4 soil was evaluated on the basis of activity attenuation of {sup 137}Cs in the gravel- and sand-size fractions.

  11. Destruction of chemical agent simulants in a supercritical water oxidation bench-scale reactor

    International Nuclear Information System (INIS)

    A new design of supercritical water oxidation (SCWO) bench-scale reactor has been developed to handle high-risk wastes resulting from munitions demilitarization. The reactor consists of a concentric vertical double wall in which SCWO reaction takes place inside an inner tube (titanium grade 2, non-porous) whereas pressure resistance is ensured by a Hastelloy C-276 external vessel. The performances of this reactor were investigated with two different kinds of chemical warfare agent simulants: OPA (a mixture of isopropyl amine and isopropyl alcohol) as the binary precursor for nerve agent of sarin and thiodiglycol [TDG (HOC2H4)2S] as the model organic sulfur heteroatom. High destruction rates based on total organic carbon (TOC) were achieved (>99.99%) without production of chars or undesired gases such as carbon monoxide and methane. The carbon-containing product was carbon dioxide whereas the nitrogen-containing products were nitrogen and nitrous oxide. Sulfur was totally recovered in the aqueous effluent as sulfuric acid. No corrosion was noticed in the reactor after a cumulative operation time of more than 250 h. The titanium tube shielded successfully the pressure vessel from corrosion

  12. 100 Area soil washing: Bench scale tests on 116-F-4 pluto crib soil

    International Nuclear Information System (INIS)

    The Pacific Northwest Laboratory conducted a bench-scale treatability study on a pluto crib soil sample from 100 Area of the Hanford Site. The objective of this study was to evaluate the use of physical separation (wet sieving), treatment processes (attrition scrubbing, and autogenous surface grinding), and chemical extraction methods as a means of separating radioactively-contaminated soil fractions from uncontaminated soil fractions. The soil washing treatability study was conducted on a soil sample from the 116-F-4 Pluto Crib that had been dug up as part of an excavation treatability study. Trace element analyses of this soil showed no elevated concentrations above typically uncontaminated soil background levels. Data on the distribution of radionuclide in various size fractions indicated that the soil-washing tests should be focused on the gravel and sand fractions of the 116-F-4 soil. The radionuclide data also showed that 137Cs was the only contaminant in this soil that exceeded the test performance goal (TPG). Therefore, the effectiveness of subsequent soil-washing tests for 116-F-4 soil was evaluated on the basis of activity attenuation of 137Cs in the gravel- and sand-size fractions

  13. Bench-scale vitrification studies with Savannah River Site mercury contaminated soil

    International Nuclear Information System (INIS)

    The Savannah River Technology Center (SRTC) has been charted by the Department of Energy (DOE)--Office of Technology Development (OTD) to investigate vitrification technology for the treatment of Low Level Mixed Wastes (LLMW). In fiscal year 1995, mercury containing LLMW streams were targeted. In order to successfully apply vitrification technology to mercury containing LLMW, the types and quantities of glass forming additives necessary for producing homogeneous glasses from the wastes have to be determined and the treatment for the mercury portion must also be determined. Selected additives should ensure that a durable and leach resistant waste form is produced, while the mercury treatment should ensure that hazardous amounts of mercury are not released into the environment. The mercury containing LLMW selected for vitrification studies at the SRTC was mercury contaminated soil from the TNX pilot-plant facility at the Savannah River Site (SRS). Samples of this soil were obtained so bench-scale vitrification studies could be performed at the SRTC to determine the optimum waste loading obtainable in the glass product without sacrificing durability and leach resistance. Vitrifying this waste stream also required offgas treatment for the capture of the vaporized mercury

  14. Safety analysis of the CSTR-1 bench-scale coal liquefaction unit

    Energy Technology Data Exchange (ETDEWEB)

    Hulburt, D.A.

    1981-05-01

    The objective of the program reported herein was to provide a Safety Analysis of the CSTR-1 bench scale unit located in Building 167 at the Pittsburgh Energy Technology Center. It was apparent that considerable effort was expended in the design and construction of the unit, and in the development of operating procedures, with regard to safety. Exhaust ventilation, H/sub 2/ and H/sub 2/S monitoring, overpressure protection, overtemperature protection, and interlock systems have been provided. Present settings on the pressure and temperature safety systems are too high, however, to insure prevention of vessel deformation or damage in all cases. While the occurrence of catastrophic rupture of a system pressure vessel (e.g., reactor, high pressure separators) is unlikely, the potential consequences to personnel are severe. Feasibility of providing shielding for these components should be considered. A more probable mode of vessel failure in the event of overpressure or overtemperature and failure of the safety system is yielding of the closure bolts followed by high pressure flow across the mating surfaces. As a minimum, shielding should be designed to restrict travel of resultant spray. The requirements for personal protective equipment are presently stated in rather broad and general terms in the operating procedures. Safe practices and procedures would be more assured if specific requirements were stated and included for each operational step. Recommendations were developed for all hazards triggered by the guidelines.

  15. Influence of Gold on Ce-Zr-Co Fluorite-Type Mixed Oxide Catalysts for Ethanol Steam Reforming

    Directory of Open Access Journals (Sweden)

    Véronique Pitchon

    2012-02-01

    Full Text Available The effect of gold presence on carbon monoxide oxidation and ethanol steam reforming catalytic behavior of two Ce-Zr-Co mixed oxides catalysts with a constant Co charge and different Ce/Zr ratios was investigated. The Ce-Zr-Co mixed oxides were obtained by the pseudo sol-gel like method, based on metallic propionates polymerization and thermal decomposition, whereas the gold-supported Ce-Zr-Co mixed oxides catalysts were prepared using the direct anionic exchange. The catalysts were characterized using XRD, TPR, and EDXS-TEM. The presence of Au in doped Ce-Zr-Co oxide catalyst decreases the temperature necessary to reduce the cobalt and the cerium loaded in the catalyst and favors a different reaction pathway, improving the acetaldehyde route by ethanol dehydrogenation, instead of the ethylene route by ethanol dehydration or methane re-adsorption, thus increasing the catalytic activity and selectivity into hydrogen.

  16. Co/Zr substitution in a cerium-zirconium oxide by catalytic steam reforming of bio-ethanol

    International Nuclear Information System (INIS)

    This work deals with the production of hydrogen by bio-ethanol catalytic steam reforming. The aim is to develop a catalyst active in ethanol conversion, selective in hydrogen and resistant to deactivation, particularly those induced by the formation of carbon deposition. The metal-support interaction being one of the keys of this challenge, catalysts in which a transition metal is inserted into an oxide by a liquid synthesis method (by the precursor method) have been developed. The initial insertion of cobalt into a cerium oxide-zirconia structure presents the advantages to increase the redox properties of the host oxide and to allow a stable reduction of a cobalt part while favoring the metal-support interaction. (O.M.)

  17. Washcoating copper catalyst on ZrO2 coated stainless steel plate with yttria sol for steam reforming of methanol in a microreactor

    Energy Technology Data Exchange (ETDEWEB)

    Wang, J.H.; Chen, K.Y. [Yuan Ze Univ., Taiwan (China). Fuel Cell Center; Shen, C.C. [Yuan Ze Univ., Taiwan (China). Dept. of Mechanical Engineering; Yeh, C.T. [Yuan Ze Univ., Taiwan (China). Fuel Cell Center, Dept. of Chemical Engineering and Materials Science

    2009-07-01

    A copper-aluminium (CuO/ZnO-Al2O3) catalyst was washcoated on a microchannel. A brushing method was used to make a slurry with commercial yttria sol for the steam reforming of methanol (SRM). Increases in adhesion were investigated by tuning the solid content (SC) and ratio of the catalyst to the binder in the slurry as well as the pH values and stirring times. Catalyst adhesion was quantified by estimating the weight losses of the catalyst layer. The catalysts were then characterized using X-ray diffraction (XRD); scanning electron microscopy (SEM); X-ray photoelectron spectroscopy (XPS); and temperature programmed reduction (TPR). The micro-reformer was then tested in a steam reforming methanol reaction at temperatures ranging between 210 and 300 degrees C. It was concluded that methanol conversion was lower at 210 degrees C, and increased with increases in temperature.

  18. Hydrogen production from raw bioethanol steam reforming: optimization of catalyst composition with improved stability against various impurities

    International Nuclear Information System (INIS)

    Usually, ethanol steam reforming is performed using pure ethanol, whereas the use of raw bioethanol is of major importance for a cost effective industrial application. Raw bioethanol contains higher alcohols as the main impurities and also aldehydes, amines, acids and esters. The effect of these impurities on the catalytic performances for ethanol steam reforming (ESR) has been studied, using a reference catalyst, Rh/MgAl2O4. It was shown that the aldehyde, the amine and methanol has no negative effect on the catalytic performances, contrary to the ester, acid and higher alcohols. The deactivation is mainly explained by coke formation favored by the presence of these impurities in the feed. In order to improve the stability of the catalyst and its performances in the presence of these deactivating impurities, the catalyst formulation, i.e. the composition of the support and of the metallic phase, was modified. The addition of rare earth elements instead of magnesium to the alumina support leads to a decrease of the strong and medium acid sites and to an increase of the basicity. On these modified supports, the dehydration reaction, leading to olefins, which are coke precursors, is disfavored, the ethanol conversion and the hydrogen yield are increased. The best catalytic performances were obtained with Rh/Y-Al2O3. Then, the metallic phase was also modified by adding a second metal (Ni, Pt or Pd). The Rh-Ni/Y-Al2O3 catalyst leads to the highest hydrogen yield. This catalyst, tested in the presence of raw bioethanol during 24h was very stable compared to the reference catalyst Rh/MgAl2O4, which was strongly deactivated after 2h of time-on-stream. (author)

  19. Effect of Ce and Zr Addition to Ni/SiO2 Catalysts for Hydrogen Production through Ethanol Steam Reforming

    Directory of Open Access Journals (Sweden)

    Jose Antonio Calles

    2015-01-01

    Full Text Available A series of Ni/Ce\\(_{x}\\Zr\\(_{1-x}\\O\\(_{2}\\/SiO\\(_{2}\\ catalysts with different Zr/Ce mass ratios were prepared by incipient wetness impregnation. Ni/SiO\\(_{2}\\, Ni/CeO\\(_{2}\\ and Ni/ZrO\\(_{2}\\ were also prepared as reference materials to compare. Catalysts' performances were tested in ethanol steam reforming for hydrogen production and characterized by XRD, H\\(_{2}\\-temperature programmed reduction (TPR, NH\\(_{3}\\-temperature programmed desorption (TPD, TEM, ICP-AES and N\\(_{2}\\-sorption measurements. The Ni/SiO\\(_{2}\\ catalyst led to a higher hydrogen selectivity than Ni/CeO\\(_{2}\\ and Ni/ZrO\\(_{2}\\, but it could not maintain complete ethanol conversion due to deactivation. The incorporation of Ce or Zr prior to Ni on the silica support resulted in catalysts with better performance for steam reforming, keeping complete ethanol conversion over time. When both Zr and Ce were incorporated into the catalyst, Ce\\(_{x}\\Zr\\(_{1-x}\\O\\(_{2}\\ solid solution was formed, as confirmed by XRD analyses. TPR results revealed stronger Ni-support interaction in the Ce\\(_{x}\\Zr\\(_{1-x}\\O\\(_{2}\\-modified catalysts than in Ni/SiO\\(_{2}\\ one, which can be attributed to an increase of the dispersion of Ni species. All of the Ni/Ce\\(_{x}\\Zr\\(_{1-x}\\O\\(_{2}\\/SiO\\(_{2}\\ catalysts exhibited good catalytic activity and stability after 8 h of time on stream at 600°. The best catalytic performance in terms of hydrogen selectivity was achieved when the Zr/Ce mass ratio was three.

  20. Ethanol steam reforming on Ni/Al2O3 catalysts: effect of the addition of Zn and Pt.

    Science.gov (United States)

    Buitrago-Sierra, R; Ruiz-Martínez, J; Serrano-Ruiz, J C; Rodríguez-Reinoso, F; Sepúlveda-Escribano, A

    2012-10-01

    Ni-based catalysts supported on Zn-modified alumina were investigated in the ethanol steam reforming reaction. A commercial γ-alumina was impregnated with different amounts of zinc nitrate (0, 2, 5, 10, 15, 20 wt.% on Zn basis), calcined, and then impregnated with nickel nitrate aqueous solutions. The samples were characterized by a number of techniques: N(2) adsorption at 77 K, X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray fluorescence (XRF), and temperature-programmed reduction (TPR). Their catalytic behavior in the ethanol steam reforming reaction was studied at 873 K, with a H(2)O/ethanol ratio of 5:1. Two effects of the presence of Zn were detected. On the one hand, zinc modifies the surface structure and the surface chemistry of the catalysts by formation of zinc aluminates, and on the other hand, zinc oxide can be reduced to metallic zinc under reaction conditions, thus modifying the catalytic properties of the active phase. The presence of Zn increases the ethanol conversion to gaseous compounds as compared with the catalyst supported on the Zn-free commercial alumina. The addition of a small amount of Pt (1 wt.%) causes a beneficial effect in the reaction. When Ni catalysts were used without a previous reduction treatment, ethylene was formed in high amounts; however, the Pt-Ni catalysts need no reduction pre-treatment to achieve high H(2) yields (close to 70%) and showed a high stability versus time on stream because of the control of the production of ethylene, a coke precursor. PMID:22796067

  1. Effect study of the support in nickel and cobalt catalysts for obtaining hydrogen from ethanol steam reforming

    International Nuclear Information System (INIS)

    A range of oxide-supported metal catalysts have been investigated for the steam reforming of ethanol for the production of hydrogen and subsequent application in fuel cells. The catalysts were synthesized by the co-precipitation and internal gelification methods using cobalt and nickel as active metals supported on aluminum, zirconium, lanthanum and cerium oxides. After prepared and calcined at 550 Cº the solids were fully characterized by different techniques such as X-rays diffraction(DRX), energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy, nitrogen adsorption (B.E.T), temperature-programmed reduction in H2 (TPR-H2) and thermogravimetric analysis. The catalytic tests were performed in a monolithic quartz reactor and submitted to different thermodynamic conditions of steam reforming of ethanol at temperatures varying from 500º C to 800 ºC. The product gas streams from the reactor were analyzed by an on-line gas chromatograph. The cobalt/nickel catalyst supported on a ceria-lanthania mixture (Co10% / Ni5% - CeO2La2O3) showed good catalytic performance in hydrogen selectivity reaching a concentration greater than 65%, when compared to other catalytic systems such as: Co10% / Ni5% - CeO2; Co10% / Ni5% - CeO2ZrO2; Co10% / Ni5% - ZrO2; Co10% / Ni5% - La2O3; Co10% / Ni5% - CeO2La2O3/K2%; Co10% / Ni5% - CeO2La2O3 / Na2%; Ni10% / Co5% - CeO2La2O3; Co-Al2O3 e Co-Al2O3CeO2. (author)

  2. Hydrogen production from raw bioethanol steam reforming: optimization of catalyst composition with improved stability against various impurities

    Energy Technology Data Exchange (ETDEWEB)

    Le Valant, A.; Can, F.; Bion, N.; Epron, F.; Duprez, D. [Laboratoire de Catalyse en Chimie organique, Univ. de Poitiers, Poitiers Cedex (France)], E-mail: florence.epron.cognet@univ-poitiers.fr

    2009-07-01

    Usually, ethanol steam reforming is performed using pure ethanol, whereas the use of raw bioethanol is of major importance for a cost effective industrial application. Raw bioethanol contains higher alcohols as the main impurities and also aldehydes, amines, acids and esters. The effect of these impurities on the catalytic performances for ethanol steam reforming (ESR) has been studied, using a reference catalyst, Rh/MgAl{sub 2}O{sub 4}. It was shown that the aldehyde, the amine and methanol has no negative effect on the catalytic performances, contrary to the ester, acid and higher alcohols. The deactivation is mainly explained by coke formation favored by the presence of these impurities in the feed. In order to improve the stability of the catalyst and its performances in the presence of these deactivating impurities, the catalyst formulation, i.e. the composition of the support and of the metallic phase, was modified. The addition of rare earth elements instead of magnesium to the alumina support leads to a decrease of the strong and medium acid sites and to an increase of the basicity. On these modified supports, the dehydration reaction, leading to olefins, which are coke precursors, is disfavored, the ethanol conversion and the hydrogen yield are increased. The best catalytic performances were obtained with Rh/Y-Al{sub 2}O{sub 3}. Then, the metallic phase was also modified by adding a second metal (Ni, Pt or Pd). The Rh-Ni/Y-Al{sub 2}O{sub 3} catalyst leads to the highest hydrogen yield. This catalyst, tested in the presence of raw bioethanol during 24h was very stable compared to the reference catalyst Rh/MgAl{sub 2}O{sub 4}, which was strongly deactivated after 2h of time-on-stream. (author)

  3. The Influence of oxide additives on Ni/Al2O3 catalysts in low temperature methane steam reforming

    International Nuclear Information System (INIS)

    Hydrogen is industrially produced by methane steam reforming. The process is catalytic and the usual catalyst is based on Ni as the active element. The main problem of this process is its inefficiency. It requires high temperatures at which Ni also favors the formation of graphite, which deactivates the catalysts. Ni has the advantage of being much cheaper than noble metal catalysts, so many researches are done in order to improve the properties of supported Ni catalysts and to decrease the temperature at which the process is energetically efficient. In order to obtain catalysts with high activity and stability, it is essential to maintain the dispersion of the active phase (Ni particles) and the stability of the support. Both properties can be improved by addition of a second oxide to the support. In this paper we present the results obtained in preparation and characterization of Ni/Al2O3 catalysts modified by addition of CeO2 and La2O3 to alumina support. The following catalysts were prepared by impregnation method: Ni/Al2O3, Ni/CeO2-Al2O3 and Ni/La2O3-Al2O3 (10 wt.% Ni and 6 wt.% additional oxide). The catalytic surface was characterized by N2 adsorption - desorption isotherms. The hydrogen - surface bond was characterized by Thermo-Programmed-Desorption (TPD) method. All catalysts were tested in steam reforming reaction of methane in the range of 600 - 700 deg. C, at atmospheric pressure working with CH4:H2O ratio of 1:3. The modified catalysts showed a better catalytic activity and selectivity for H2 and CO2 formation, at lower temperatures than the simple Ni/Al2O3 catalyst. (authors)

  4. Preparation and study of porous uranium oxides as supports for new catalysts of steam reforming of methane

    International Nuclear Information System (INIS)

    We describe the method of synthesis of the porous uranium oxides (U3O8 and UO2) with specific surface area as high as 10-15 m2/g. Physico-chemical structure and properties of these materials were studied by X-ray diffraction, scanning electron microscopy and adsorption techniques. Porous U3O8 was used as a support for Ni- and Ru-catalysts for steam reforming of methane for new ICAR-process of direct nuclear-to-chemical energy conversion (Int. J. Hydrogen Energy 18 (1) (1993)) Catalytic activity as a function of the metal (Ni or Ru) content, temperature and contact time was studied in non-gradient catalytic reactor at P=1 atm and T=600-780 C. The catalysts studied were shown to be very active in methane reforming by steam and allow to reach at these conditions the hydrogen production rate as high as 17-18 n cm3/s per 1 gram of the catalyst. The reaction rate obeys the law r=k0 exp(-Ea/RT)(pm-p*m), where pm is a partial pressure of methane, p*m is close to the equilibrium pressure of methane at temperature T. The activation energy Ea was found to be 54 kJ/mol for Ru/U3O8 catalysts. To reduce the expected contamination of the produced syn-gas by radioactive products of nuclear splitting under application in the ICAR process we build up a thin oxide (MgO, Al2O3) layer, coating the porous uranium particle. The results of the coating study are also presented. ((orig.))

  5. HYDROGEN PRODUCTION BY STEAM REFORMING OF BIO-OIL AQUEOUS FRACTION OVER Ni/CeO2-ZrO2 CATALYST%催化剂Ni/CeO2-ZrO2催化生物油水溶性组分重整制氢

    Institute of Scientific and Technical Information of China (English)

    程菲菲; 胡蓉蓉; 闫常峰

    2011-01-01

    Catalytic generation of hydrogen by steam reforming of bio-oil aqueous fraction over a series of self-made Ni/CeO2-ZrO2 catalysts and commercial nickel-based catalysts (Z417) was studied in a bench scale fixed-bed reactor. Effects of water to bio-oil ratios, reaction temperature, and the loaded weight of Ni on the performance of Ni/CeO2-ZrO2catalysts were examined. The results shown that the Ni/CeO2-ZrO2 catalyst with Ni loaded weight 12% was superior to other catalysts. Under the conditions of water to bio-oil ratio 4. 9 and reaction temperature 800t, H2 yield reaches the highest of 67.8% and H2 selectivity of 61.8% were obtained.%利用固定床反应器对一系列自制催化剂Ni/CeO2-ZrO2和商业镍基催化剂Z417在生物油水溶性组分重整制氢反应中的催化性能进行考察,研究了活性金属Ni的负载量、反应温度、水油比对催化剂活性的影响.实验结果表明:Ni负载量为12wt%的催化剂Ni/CeO2-ZrO2在生物油水溶性组分重整制氢反应中表现出最佳催化活性,当反应温度为800C和水油比为4.9时,氢产率达到最大值67.8%,氢的选择性较高,为61.8%.

  6. Hydrogen and syngas production from two-step steam reforming of methane using CeO2 as oxygen carrier

    Institute of Scientific and Technical Information of China (English)

    Xing Zhu; Hua Wang; Yonggang Wei; Kongzhai Li; Xianming Cheng

    2011-01-01

    CeO2 oxygen carrier was prepared by precipitation method and tested by two-step steam reforming of methane (SRM).Two-step SRM for hydrogen and syngas generation is investigated in a fixed-bed reactor.Methane is directly converted to syngas at a H2/CO ratio close to 2∶ 1 at a high temperature (above 750 ℃) by the lattice oxygen of CeO2; methane cracking is found when the reduction degree of CeO2 was above 5.0% at 850 ℃ in methane isothermal reaction.CeO2-δ obtained from methane isothermal reaction can split water to generate CO-free hydrogen and renew its lattice oxygen at 700 ℃; simultaneously, deposited carbon is selectively oxidized to CO2 by steam following the reaction (C+2H2O→CO2+2H2).Slight deactivation in terms of amounts of desired products (syngas and hydrogen) is observed in ten repetitive two-step SRM process due to the carbon deposition on CeO2 surface as well as sintering of CeO2.

  7. A turbulent Eulerian multi-fluid reactive flow model and its application in modelling sorption enhanced steam methane reforming

    International Nuclear Information System (INIS)

    A turbulent multi-fluid reactive fluid model is presented in the paper, which is a combination of a kinetic theory granular flow multi-fluid model(Chao et al., 2011) and the reaction kinetics description(Lindborg, 2008). A two dimensional in-house code was developed to simulate the gas-catalyst-sorbent three-phase reactive flow in the sorption enhanced steam methane reforming fluidized bed reactor. In the simulation, Ca-based sorbents and Ni/MgAl2O3 catalysts are used. The simulation results show that a high production of hydrogen in SE-SMR is obtained compared with the conventional SMR process. The increase of the gas fluidization velocity does not affect the purity of the product hydrogen apparently,while it can shorten the time to get to the breakthrough apparently. The increase of the steam/carbon ratio can increase the purity of the product hydrogen. A homogeneous gas temperature distribution is found which is due to the gas, particle turbulent flows and the heat balance of the SMR-CO2 adsorption reactions. These simulation results are in good agreement with the experimental results from Johnsen et al. (2006a).

  8. CFD simulation with detailed chemistry of steam reforming of methane for hydrogen production in an integrated micro-reactor

    Energy Technology Data Exchange (ETDEWEB)

    Zhai, Xuli; Cheng, Yinhong; Jin, Yong; Cheng, Yi [Department of Chemical Engineering, Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology, Tsinghua University, Beijing 100084 (China); Ding, Shi [Department of Chemical Engineering, Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology, Tsinghua University, Beijing 100084 (China); Research Institute of Petroleum Processing, SINOPEC, Beijing 100083 (China)

    2010-06-15

    micro-reactor has drawn more and more attention in recent years due to the process intensification on basic transport phenomena in micro-channels, which would often lead to the improved reactor performance. Steam reforming of methane (SRM) in micro-reactor has great potential to realize a low-cost, compact process for hydrogen production via an evident shortening of reaction time from seconds to milliseconds. This work focuses on the detailed modeling and simulation of a micro-reactor design for SRM reaction with the integration of a micro-channel for Rh-catalyzed endothermic reaction, a micro-channel for Pt-catalyzed exothermic reaction and a wall in between with Rh or Pt-catalyst coated layer. The elementary reaction kinetics for SRM process is adopted in the CFD model, while the combustion channel is described by global reaction kinetics. The model predictions were quantitatively validated by the experimental data in the literature. For the extremely fast reactions in both channels, the simulations indicated the significance of the heat conduction ability of the reactor wall as well as the interplay between the exothermic and endothermic reactions (e.g., the flow rate ratio of fuel gas to reforming gas). The characteristic width of 0.5 mm is considered to be a suitable channel size to balance the trade-off between the heat transfer behavior in micro-channels and the easy fabrication of micro-channels. (author)

  9. Computational Investigation of the Thermochemistry and Kinetics of Steam Methane Reforming Over a Multi-Faceted Nickel Catalyst

    KAUST Repository

    Blaylock, D. Wayne

    2011-08-20

    A microkinetic model of steam methane reforming over a multi-faceted nickel surface using planewave, periodic boundary condition density functional theory is presented. The multi-faceted model consists of a Ni(111) surface, a Ni(100) surface, and nickel step edge sites that are modeled as a Ni(211) surface. Flux and sensitivity analysis are combined to gain an increased understanding of the important reactions, intermediates, and surface facets in SMR. Statistical thermodynamics are applied to allow for the investigation of SMR under industrially-relevant conditions (e.g., temperatures in excess of 500 °C and pressures in excess of 1 bar). The most important surface reactions are found to occur at the under-coordinated step edge sites modeled using the Ni(211) surface as well as on the Ni(100) surface. The primary reforming pathway is predicted to be through C*+ O*→ CO*at high temperatures; however, hydrogen-mediated reactions such as C*+ OH*→ COH*and C.H.*+ O*→ CHO*are predicted to become more important at low temperatures. The rate-limiting reactions are predicted to be dissociative chemisorption of methane in addition to the aforementioned C-O addition reactions. © 2011 Springer Science+Business Media, LLC.

  10. A novel approach to the experimental study on methane/steam reforming kinetics using the Orthogonal Least Squares method

    Science.gov (United States)

    Sciazko, Anna; Komatsu, Yosuke; Brus, Grzegorz; Kimijima, Shinji; Szmyd, Janusz S.

    2014-09-01

    For a mathematical model based on the result of physical measurements, it becomes possible to determine their influence on the final solution and its accuracy. However, in classical approaches, the influence of different model simplifications on the reliability of the obtained results are usually not comprehensively discussed. This paper presents a novel approach to the study of methane/steam reforming kinetics based on an advanced methodology called the Orthogonal Least Squares method. The kinetics of the reforming process published earlier are divergent among themselves. To obtain the most probable values of kinetic parameters and enable direct and objective model verification, an appropriate calculation procedure needs to be proposed. The applied Generalized Least Squares (GLS) method includes all the experimental results into the mathematical model which becomes internally contradicted, as the number of equations is greater than number of unknown variables. The GLS method is adopted to select the most probable values of results and simultaneously determine the uncertainty coupled with all the variables in the system. In this paper, the evaluation of the reaction rate after the pre-determination of the reaction rate, which was made by preliminary calculation based on the obtained experimental results over a Nickel/Yttria-stabilized Zirconia catalyst, was performed.

  11. A comprehensive energy–exergy-based assessment and parametric study of a hydrogen production process using steam glycerol reforming

    International Nuclear Information System (INIS)

    Various assessment tools are applied to comprehensively investigate a glycerol-to-hydrogen production system. These tools investigate the chemical reactions, design and simulate the entire hydrogen production process, study the energetic and exergetic performances and perform parametric analyses (using intuitive and design of experiment-based methods). Investigating the chemical reaction of steam glycerol reforming reveals that the optimal conditions, determined based on maximizing the hydrogen production while minimizing the methane and carbon monoxide contents and coke formation, can be achieved at a reforming temperature and a water-to-glycerol feed ratio (WGFR) of 950 K and 9, respectively. The thermal and exergetic efficiencies of the resulting process are 66.6% and 59.9%, respectively. These findings are lower than those cited in the literature and relative to other reformates (methane, ethanol and methanol). The parametric investigation indicates that the performance of the process (energetic and exergetic) could be ensured by using an appropriate and judiciously selected combination of the reactor temperature and WGFR. Based on the parametric energetic and exergetic investigation, WGFR = 6 and T = 1100 K appear to be the most accurate parameters for the entire glycerol-to-hydrogen process. For this recommend configuration, the thermal and exergetic efficiencies are 78.1% and 66.1%, respectively. - Highlights: • Energy and exergy analysis are used to assess glycerol-to-hydrogen process. • Recommended conditions for glycerol-to-hydrogen process are WGFR = 6 and T = 1100 K. • For recommend conditions, thermal and exergetic efficiencies are 78.1% and 66.1%. • Energy and exergy consideration should be included by engineers and scientists

  12. Bench-Scale Silicone Process for Low-Cost CO{sub 2} Capture

    Energy Technology Data Exchange (ETDEWEB)

    Fresia, Megan; Vogt, Kirk

    2013-12-31

    GE Global Research is developing technology to remove carbon dioxide (CO{sub 2}) from the flue gas of coal-fired power plants. A mixture of 3-aminopropyl end-capped polydimethylsiloxane (GAP-1m) and triethylene glycol (TEG) is the preferred CO{sub 2} capture solvent. GE Global Research was contracted by the Department of Energy to test a bench-scale continuous CO{sub 2} absorption/desorption system using a GAP-1m/TEG mixture as the solvent. SiVance LLC was sub-contracted to provide the GAP-1m material and conduct an Environmental, Health, and Safety (EH&S) assessment for a 550 MW coal-fired power plant. Five components of the solvent, CAS#2469-55-8 (GAP-0), CAS#106214-84-0 (GAP-1-4), TEG, and methanol and xylene (minor contaminants from the aminosilicone) are included in this assessment. One by-product, GAP-1m/SOX salt, and dodecylbenzenesulfonic acid (DDBSA) were also identified for analysis. All of the solvent components and DDBSA are listed on the EPA’s TSCA Inventory allowing companies to manufacture and use the chemicals commercially. The toxicological effects of each component were defined, and control mechanisms necessary to comply with U.S. EH&S regulations are summarized. An engineering and control system, including environmental abatement, was described for minimizing exposure and release of the chemical components. Proper handling and storage recommendations are made for each chemical to minimize risk to workers and the surrounding community.

  13. Bench-scale arc melter for R ampersand D in thermal treatment of mixed wastes

    International Nuclear Information System (INIS)

    A small dc arc melter was designed and constructed to run bench-scale investigations on various aspects of development for high-temperature (1,500-1,800 degrees C) processing of simulated transuranic-contaminated waste and soil located at the Radioactive Waste Management Complex (RWMC). Several recent system design and treatment studies have shown that high-temperature melting is the preferred treatment. The small arc melter is needed to establish techniques and procedures (with surrogates) prior to using a similar melter with the transuranic-contaminated wastes in appropriate facilities at the site. This report documents the design and construction, starting and heating procedures, and tests evaluating the melter's ability to process several waste types stored at the RWMC. It is found that a thin graphite strip provides reliable starting with initial high current capability for partially melting the soil/waste mixture. The heating procedure includes (1) the initial high current-low voltage mode, (2) a low current-high voltage mode that commences after some slag has formed and arcing dominates over the receding graphite conduction path, and (3) a predominantly Joule heating mode during which the current can be increased within the limits to maintain relatively quiescent operation. Several experiments involving the melting of simulated wastes are discussed. Energy balance, slag temperature, and electrode wear measurements are presented. Recommendations for further refinements to enhance its processing capabilities are identified. Future studies anticipated with the arc melter include waste form processing development; dissolution, retention, volatilization, and collection for transuranic and low-level radionuclides, as well as high vapor pressure metals; electrode material development to minimize corrosion and erosion; refractory corrosion and/or skull formation effects; crucible or melter geometry; metal oxidation; and melt reduction/oxidation (redox) conditions

  14. Bioleaching of heavy metals from soil using fungal-organic acids : bench scale testing

    Energy Technology Data Exchange (ETDEWEB)

    Cathum, S.J.; Ousmanova, D.; Somers, A.; Punt, M. [SAIC Canada, Ottawa, ON (Canada); Brown, C.E. [Environment Canada, Ottawa, ON (Canada). Emergencies Engineering Division]|[Environment Canada, Ottawa, ON (Canada). Environmental Technology Centre

    2006-07-01

    The ability of fungi to solubilize metals from solid materials may present new opportunities in environmental remediation. This paper presented details of a bench scale experiment that evaluated the leaching of heavy metals from contaminated soil using in situ fungal-generated organic acids. Rice was used as the growing media for organic acid production by A. foetidus. The cultivated fungus was placed on large pieces of potato-dextrose agar (PDA) plates and suspended in 5 L of sterilized water. The cooked rice was inoculated by pouring the 5 L spore suspension over the rice layer. Soil was obtained from a soil pile impacted with heavy metals at a private industrial site and augmented with Pb-contaminated soil. A polyethylene tub was used with a drain pipe leading to a leachate vessel. Crushed stone was spread over the bottom of the tub to assist leachate drainage. Approximately 45 kg of the contaminated soil was spread evenly over the stone layer to a depth of 10 cm. The concentrated spore suspension was sprinkled over the rice. Each week the leachate collection vessel was removed from the bioleaching system and the fine soil particles were allowed to settle. A control was run using the contaminated soil and solid substrate without fungus. Growth of A. foetidus was observed in both control experiment and test experiment after a period of 35 days. The pH of the leachate was measured as the fungal growth progressed. The process was assessed using ICP Mass Spectroscopy and electron spectroscopy, which showed that approximately 65 g of heavy metals were mobilized from 45 kg of soil, and that the biological leaching process resulted in greater mobilization of heavy metals relative to the control experiment. It was concluded that organic acids generated by A. foetidus were capable of leaching heavy metals from the soil. 30 refs., 4 tabs., 15 figs.

  15. Biotreatment of chlorpyrifos in a bench scale bioreactor using Psychrobacter alimentarius T14.

    Science.gov (United States)

    Khalid, Saira; Hashmi, Imran

    2016-01-01

    Bacteria tolerant to high pesticide concentration could be used for designing an efficient treatment technology. Bacterial strains T14 was isolated from pesticide-contaminated soil in mineral salt medium (MSM) and identified as Psychrobacter alimentarius T14 using 16S rRNA gene sequence analysis. Bench scale bioreactor was evaluated for biotreatment of high Chlorpyrifos (CP) concentration using P. alimentarius T14. Effect of various parameters on bioreactor performance was examined and optimum removal was observed at optical density (OD600 nm): 0.8; pH: 7.2; CP concentration: 300 mg L(-1) and hydraulic retention time: 48 h. At optimum conditions, 70.3/79% of CP/chemical oxygen demand (COD) removal was achieved in batch bioreactors. In addition, P. alimentarius T14 achieved 95/91, 62.3/75, 69.8/64% CP/COD removal efficiency with addition of CS (co-substrates), CS1 (yeast extract + synthetic wastewater), CS2 (glucose + synthetic wastewater) and CS3 (yeast extract), respectively. Addition of CS1 to bioreactor could accelerate CP removal rate up to many cycles with considerable efficiency. However, accumulation of 3, 5, 6-trichloro-2-pyridinol affects reactor performance in cyclic mode. First-order rate constant k1 0.062 h(-1) and t1/2 11.1 h demonstrates fast degradation. Change in concentration of total chlorine and nitrogen could be the result of complete mineralization. Photodegradation of CP in commercial product was more than its pure form. Commercial formulation accelerated photodegradation process; however no effect on biodegradation process was observed. After bio-photodegradation, negligible toxicity for seeds of Triticum aestivum was observed. Study suggests an efficient treatment of wastewater containing CP and its metabolites in batch bioreactors could be achieved using P. alimentarius. PMID:26144866

  16. Bench-scale arc melter for R&D in thermal treatment of mixed wastes

    Energy Technology Data Exchange (ETDEWEB)

    Kong, P.C.; Grandy, J.D.; Watkins, A.D.; Eddy, T.L.; Anderson, G.L.

    1993-05-01

    A small dc arc melter was designed and constructed to run bench-scale investigations on various aspects of development for high-temperature (1,500-1,800{degrees}C) processing of simulated transuranic-contaminated waste and soil located at the Radioactive Waste Management Complex (RWMC). Several recent system design and treatment studies have shown that high-temperature melting is the preferred treatment. The small arc melter is needed to establish techniques and procedures (with surrogates) prior to using a similar melter with the transuranic-contaminated wastes in appropriate facilities at the site. This report documents the design and construction, starting and heating procedures, and tests evaluating the melter`s ability to process several waste types stored at the RWMC. It is found that a thin graphite strip provides reliable starting with initial high current capability for partially melting the soil/waste mixture. The heating procedure includes (1) the initial high current-low voltage mode, (2) a low current-high voltage mode that commences after some slag has formed and arcing dominates over the receding graphite conduction path, and (3) a predominantly Joule heating mode during which the current can be increased within the limits to maintain relatively quiescent operation. Several experiments involving the melting of simulated wastes are discussed. Energy balance, slag temperature, and electrode wear measurements are presented. Recommendations for further refinements to enhance its processing capabilities are identified. Future studies anticipated with the arc melter include waste form processing development; dissolution, retention, volatilization, and collection for transuranic and low-level radionuclides, as well as high vapor pressure metals; electrode material development to minimize corrosion and erosion; refractory corrosion and/or skull formation effects; crucible or melter geometry; metal oxidation; and melt reduction/oxidation (redox) conditions.

  17. Bench-scale enhanced sludge washing and gravity settling of Hanford Tank C-106 Sludge

    International Nuclear Information System (INIS)

    This report summarizes the results of a bench-scale sludge pretreatment demonstration of the Hanford baseline flowsheet using liter-quantities of sludge from Hanford Site single-shell tank 241-C-106 (tank C-106). The leached and washed sludge from these tests provided Envelope D material for the contractors supporting Tank Waste Remediation System (TWRS) Privatization. Pretreatment of the sludge included enhanced sludge washing and gravity settling tests and providing scale-up data for both these unit operations. Initial and final solids as well as decanted supernatants from each step of the process were analyzed chemically and radiochemically. The results of this work were compared to those of Lumetta et al. (1996a) who performed a similar experiment with 15 grams of C-106, sludge. A summary of the results are shown in Table S.1. Of the major nonradioactive components, those that were significantly removed with enhanced sludge washing included aluminum (31%), chromium (49%), sodium (57%), and phosphorus (35%). Of the radioactive components, a significant amount of 137Cs (49%) were removed during the enhanced sludge wash. Only a very small fraction of the remaining radionuclides were removed, including 90Sr (0.4%) and TRU elements (1.5%). These results are consistent with those of the screening test. All of the supernatants (both individually and as a blend) removed from these washing steps, once vitrified as LLW glasses (at 20 wt% Na2O), would be less than NRC Class C in TRU elements and less than NRC Class B in 90Sr

  18. Bench-scale studies of reactor-based treatment of fuel-contaminated soils

    International Nuclear Information System (INIS)

    Biological treatment of hazardous wastes from accidental spills or underground storage tank leaks has generated interest in bioremediation as a natural, economical mechanism for site decontamination. Because of drawbacks of batch systems, and the successful use of continuous flow treatment of wastewater for several decades, it was felt that continuous treatment of such soils would be a feasible alternative treatment technique. Therefore, bench-scale bioreactor treatability studies were conducted and used contaminated soil made in the laboratory using No. 2 diesel fuel and sand. Contamination levels studied were from 1,335--6,675 mg (TPH) as derived from No. 2 fuel oil per kg sand. Variation in mean cell age was obtained between reactors, with sufficient nutrients and oxygen made available to ensure the fuel oil organics were the only limit to microbial growth. A theoretical biokinetic model was formulated based on Monod's theory of limiting substrate and continuous cultures. Biokinetic constants and removal efficiencies were evaluated. The off-gases, CO2, and volatile hydrocarbons were monitored for mass balance analysis of the process. The solids retention times for evaluating final TPH concentration of 100 mg/kg were also calculated. Removal efficiencies of up to 91% were attained at a loading of 1,335 mg TPH/kg wet sand, operated at a biological solid retention time (BSRT) of 60 days. Experiments also showed that TPH desorption and volatilization were not rate-limiting in the overall removal process. Sand-to-moisture ratios in excess of 3:1 were also shown to retard TPH removal rates very little. However, biokinetic constants were found to vary over a range of values. This was particularly true at varying diesel loading levels. Nevertheless, significant removal efficiency (up to 86%) was noted at the highest loading level tested, 6,675 mg TPH/kg wet sand

  19. Results of bench-scale plasma system testing in support of the Plasma Hearth Process

    International Nuclear Information System (INIS)

    The Plasma Hearth Process (PHP) is a high-temperature process that destroys hazardous organic components and stabilizes the radioactive components and hazardous metals in a leach-resistant vitreous slag waste form. The PHP technology development program is targeted at mixed waste that cannot be easily treated by conventional means. For example, heterogeneous debris, which may contain hazardous organics, toxic metals, and radionuclides, is difficult to characterize and cannot be treated with conventional thermal, chemical, or physical treatment methods. A major advantage of the PHP over other plasma processes is its ability to separate nonradioactive, non-hazardous metals from the non-metallic and radioactive components which are contained in the vitreous slag. The overall PHP program involves the design, fabrication, and operation of test hardware to demonstrate and certify that the PHP concept is viable for DOE waste treatment. The program involves bench-scale testing of PHP equipment in radioactive service, as well as pilot-scale demonstration of the PHP concept using nonradioactive, surrogate test materials. The fate of secondary waste streams is an important consideration for any technology considered for processing mixed waste. The main secondary waste stream generated by the PHP is flyash captured by the fabric- filter baghouse. The PHP concept is that flyash generated by the process can, to a large extent, be treated by processing this secondary waste stream in the PHP. Prior to the work presented in the paper, however, the PHP project has not quantitatively demonstrated the ability to treat PHP generated flyash. A major consideration is the quantity of radionuclides and RCRA-regulated metals in the flyash that can be retained the resultant waste form

  20. Bench-scale experimental determination of the thermal diffusivity of crushed tuff

    International Nuclear Information System (INIS)

    A bench-scale experiment was designed and constructed to determine the effective thermal diffusivity of crushed tuff. Crushed tuff particles ranging from 12.5 mm to 37.5 mm (0.5 in. to 1.5 in.) were used to fill a cylindrical volume of 1.58 m3 at an effective porosity of 0.48. Two iterations of the experiment were completed; the first spanning approximately 502 hours and the second 237 hours. Temperatures near the axial heater reached 700 degrees C, with a significant volume of the test bed exceeding 100 degrees C. Three post-test analysis techniques were used to estimate the thermal diffusivity of the crushed tuff. The first approach used nonlinear parameter estimation linked to a one dimensional radial conduction model to estimate thermal diffusivity from the first 6 hours of test data. The second method used the multiphase TOUGH2 code in conjunction with the first 20 hours of test data not only to estimate the crushed tuffs thermal diffusivity, but also to explore convective behavior within the test bed. Finally, the nonlinear conduction code COYOTE-II was used to determine thermal properties based on 111 hours of cool-down data. The post-test thermal diffusivity estimates of 5.0 x 10-7 m2/s to 6.6 x 10-7 m2/s were converted to effective thermal conductivities and compared to estimates obtained from published porosity-based relationships. No obvious match between the experimental data and published relationships was found to exist; however, additional data for other particle sizes and porosities are needed

  1. Investigation of E. coli and Virus Reductions Using Replicate, Bench-Scale Biosand Filter Columns and Two Filter Media

    OpenAIRE

    Mark Elliott; Stauber, Christine E.; DiGiano, Francis A.; Anna Fabiszewski de Aceituno; Sobsey, Mark D.

    2015-01-01

    The biosand filter (BSF) is an intermittently operated, household-scale slow sand filter for which little data are available on the effect of sand composition on treatment performance. Therefore, bench-scale columns were prepared according to the then-current (2006–2007) guidance on BSF design and run in parallel to conduct two microbial challenge experiments of eight-week duration. Triplicate columns were loaded with Accusand silica or crushed granite to compare virus and E. coli reduction p...

  2. Process to Accomplish Autothermal or Steam Reforming Via a Reciprocating Compression Device

    Energy Technology Data Exchange (ETDEWEB)

    Lyons, David K.; James, Robert; Berry, David A.; Gardern, Todd

    2004-09-21

    The invention provides a method and apparatus for producing a synthesis gas from a variety of hydrocarbons. The apparatus (device) consists of a semi-batch, non-constant volume reactor to generate a synthesis gas. While the apparatus feeds mixtures of air, steam, and hydrocarbons into a cylinder where work is performed on the fluid by a piston to adiabatically raise its temperature without heat transfer from an external source.

  3. Ni-Based Catalysts for Low Temperature Methane Steam Reforming: Recent Results on Ni-Au and Comparison with Other Bi-Metallic Systems

    Directory of Open Access Journals (Sweden)

    Anna M. Venezia

    2013-06-01

    Full Text Available Steam reforming of light hydrocarbons provides a promising method for hydrogen production. Ni-based catalysts are so far the best and the most commonly used catalysts for steam reforming because of their acceptably high activity and significantly lower cost in comparison with alternative precious metal-based catalysts. However, nickel catalysts are susceptible to deactivation from the deposition of carbon, even when operating at steam-to-carbon ratios predicted to be thermodynamically outside of the carbon-forming regime. Reactivity and deactivation by carbon formation can be tuned by modifying Ni surfaces with a second metal, such as Au through alloy formation. In the present review, we summarize the very recent progress in the design, synthesis, and characterization of supported bimetallic Ni-based catalysts for steam reforming. The progress in the modification of Ni with noble metals (such as Au and Ag is discussed in terms of preparation, characterization and pretreatment methods. Moreover, the comparison with the effects of other metals (such as Sn, Cu, Co, Mo, Fe, Gd and B is addressed. The differences of catalytic activity, thermal stability and carbon species between bimetallic and monometallic Ni-based catalysts are also briefly shown.

  4. Catalytic Steam Reforming of Toluene as a Model Compound of Biomass Gasification Tar Using Ni-CeO2/SBA-15 Catalysts

    Directory of Open Access Journals (Sweden)

    Erik Dahlquist

    2013-07-01

    Full Text Available Nickel supported on SBA-15 doped with CeO2 catalysts (Ni-CeO2/SBA-15 was prepared, and used for steam reforming of toluene which was selected as a model compound of biomass gasification tar. A fixed-bed lab-scale set was designed and employed to evaluate the catalytic performances of the Ni-CeO2/SBA-15 catalysts. Experiments were performed to reveal the effects of several factors on the toluene conversion and product gas composition, including the reaction temperature, steam/carbon (S/C ratio, and CeO2 loading content. Moreover, the catalysts were subjected to analysis of their carbon contents after the steam reforming experiments, as well as to test the catalytic stability over a long experimental period. The results indicated that the Ni-CeO2/SBA-15 catalysts exhibited promising capabilities on the toluene conversion, anti-coke deposition and catalytic stability. The toluene conversion reached as high as 98.9% at steam reforming temperature of 850 °C and S/C ratio of 3 using the Ni-CeO2(3wt%/SBA-15 catalyst. Negligible coke formation was detected on the used catalyst. The gaseous products mainly consisted of H2 and CO, together with a little CO2 and CH4.

  5. Hydrogen-Rich Gas Production by Sorption Enhanced Steam Reforming of Woodgas Containing TAR over a Commercial Ni Catalyst and Calcined Dolomite as CO2 Sorbent

    Directory of Open Access Journals (Sweden)

    Vincenzo Naso

    2013-07-01

    Full Text Available The aim of this work was the evaluation of the catalytic steam reforming of a gaseous fuel obtained by steam biomass gasification to convert topping atmosphere residue (TAR and CH4 and to produce pure H2 by means of a CO2 sorbent. This experimental work deals with the demonstration of the practical feasibility of such concepts, using a real woodgas obtained from fluidized bed steam gasification of hazelnut shells. This study evaluates the use of a commercial Ni catalyst and calcined dolomite (CaO/MgO. The bed material simultaneously acts as reforming catalyst and CO2 sorbent. The experimental investigations have been carried out in a fixed bed micro-reactor rig using a slipstream from the gasifier to evaluate gas cleaning and upgrading options. The reforming/sorption tests were carried out at 650 °C while regeneration of the sorbent was carried out at 850 °C in a nitrogen environment. Both combinations of catalyst and sorbent are very effective in TAR and CH4 removal, with conversions near 100%, while the simultaneous CO2 sorption effectively enhances the water gas shift reaction producing a gas with a hydrogen volume fraction of over 90%. Multicycle tests of reforming/CO2 capture and regeneration were performed to verify the stability of the catalysts and sorbents to remove TAR and capture CO2 during the duty cycle.

  6. Production of hydrogen via steam reforming of biofuels on Ni/CeO{sub 2}-Al{sub 2}O{sub 3} catalysts promoted by noble metals

    Energy Technology Data Exchange (ETDEWEB)

    Profeti, Luciene P.R.; Ticianelli, Edson A.; Assaf, Elisabete M. [Universidade de Sao Paulo, Instituto de Quimica de Sao Carlos, C.P. 780, CEP 13560-970, Sao Carlos - SP (Brazil)

    2009-06-15

    The catalytic activity of Ni/CeO{sub 2}-Al{sub 2}O{sub 3} catalysts modified with noble metals (Pt, Ir, Pd and Ru) was investigated for the steam reform of ethanol and glycerol. The catalysts were characterized by the following techniques: Energy-dispersive X-ray, BET, X-ray diffraction, temperature-programmed reduction, UV-vis diffuse reflectance spectroscopy and X-ray absorption near edge structure (XANES). The results showed that the formation of inactive nickel aluminate was prevented by the presence of CeO{sub 2} dispersed on alumina. The promoting effect of noble metals included a decrease in the reduction temperatures of NiO species interacting with the support, due to the hydrogen spillover effect. It was seen that the addition of noble metal stabilized the Ni sites in the reduced state along the reforming reaction, increasing the ethanol and glycerol conversions and decreasing the coke formation. The higher catalytic performance for the ethanol steam reforming at 600 C and glycerol steam reforming was obtained for the NiPd and NiPt catalysts, respectively, which presented an effluent gaseous mixture with the highest H{sub 2} yield with reasonably low amounts of CO. (author)

  7. Thermodynamic simulation of biomass gas steam reforming for a solid oxide fuel cell (SOFC system

    Directory of Open Access Journals (Sweden)

    A. Sordi

    2009-12-01

    Full Text Available This paper presents a methodology to simulate a small-scale fuel cell system for power generation using biomass gas as fuel. The methodology encompasses the thermodynamic and electrochemical aspects of a solid oxide fuel cell (SOFC, as well as solves the problem of chemical equilibrium in complex systems. In this case the complex system is the internal reforming of biomass gas to produce hydrogen. The fuel cell input variables are: operational voltage, cell power output, composition of the biomass gas reforming, thermodynamic efficiency, electrochemical efficiency, practical efficiency, the First and Second law efficiencies for the whole system. The chemical compositions, molar flows and temperatures are presented to each point of the system as well as the exergetic efficiency. For a molar water/carbon ratio of 2, the thermodynamic simulation of the biomass gas reforming indicates the maximum hydrogen production at a temperature of 1070 K, which can vary as a function of the biomass gas composition. The comparison with the efficiency of simple gas turbine cycle and regenerative gas turbine cycle shows the superiority of SOFC for the considered electrical power range.

  8. Soluble Microbial Product Characterization of Biofilm Formation in Bench-Scale

    KAUST Repository

    Mines, Paul

    2012-12-01

    The biological process known as activated sludge (AS) in conjunction with membrane separation technology for the treatment of wastewater has been employed for over four decades. While, membrane biological reactors (MBR) are now widely employed, the phenomenon of membrane fouling is still the most significant factor leading to performance decline of MBRs. Although much research has been done on the subject of MBR fouling over the past two decades, many questions remain unanswered, and consensus within the scientific community is rare. However, research has led to one system parameter generally being regarded as a contributor to membrane fouling, extracellular polymeric compounds (EPS). EPS, and more specifically, the soluble fraction of EPS known as soluble microbial products (SMP), must be further investigated in order to better understand membrane fouling. The biological activity and performance of the MBR is affected by myriad operational parameters, which in turn affects the SMP generated. A commonly varied operational parameter is, depending on the specific treatment needs of a MBR, the sludge retention time (SRT). This study aims to characterize the SMP in three bench-scale MBRs as the SRT is gradually lowered. By studying how the SMP change as the operation of the system is altered, greater understanding of how SMP are related to fouling can be achieved. At the onset of the study, a steady state was established in the system with a SRT of 20 days. Upon stabilization of a 20 day SRT, the system was gradually transitioned to a five and a half day SRT, in stepwise adjustments. Initially, both the trans-membrane pressure (TMP) and the SMP concentrations were at relatively low values, indicating the presence of minimal amounts of biofilm on the membrane surfaces. As the system was altered and more activated sludge was wasted from the reactors, the SRT inherently decreased. As the lower SRT was transitioned and established, the data from TMP measurements, as well

  9. Bench Scale Thin Film Composite Hollow Fiber Membranes for Post-Combustion Carbon Dioxide Capture

    Energy Technology Data Exchange (ETDEWEB)

    Glaser, Paul [General Electric Global Research, Niskayuna, NY (United States); Bhandari, Dhaval [General Electric Global Research, Niskayuna, NY (United States); Narang, Kristi [General Electric Global Research, Niskayuna, NY (United States); McCloskey, Pat [General Electric Global Research, Niskayuna, NY (United States); Singh, Surinder [General Electric Global Research, Niskayuna, NY (United States); Ananthasayanam, Balajee [General Electric Global Research, Niskayuna, NY (United States); Howson, Paul [General Electric Global Research, Niskayuna, NY (United States); Lee, Julia [General Electric Global Research, Niskayuna, NY (United States); Wroczynski, Ron [General Electric Global Research, Niskayuna, NY (United States); Stewart, Frederick [Idaho National Lab. (INL), Idaho Falls, ID (United States); Orme, Christopher [Idaho National Lab. (INL), Idaho Falls, ID (United States); Klaehn, John [Idaho National Lab. (INL), Idaho Falls, ID (United States); McNally, Joshua [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rownaghi, Ali [Georgia Inst. of Technology, Atlanta, GA (United States); Lu, Liu [Georgia Inst. of Technology, Atlanta, GA (United States); Koros, William [Georgia Inst. of Technology, Atlanta, GA (United States); Goizueta, Roberto [Georgia Inst. of Technology, Atlanta, GA (United States); Sethi, Vijay [Western Research Inst., Laramie, WY (United States)

    2015-04-01

    GE Global Research, Idaho National Laboratory (INL), Georgia Institute of Technology (Georgia Tech), and Western Research Institute (WRI) proposed to develop high performance thin film polymer composite hollow fiber membranes and advanced processes for economical post-combustion carbon dioxide (CO2) capture from pulverized coal flue gas at temperatures typical of existing flue gas cleanup processes. The project sought to develop and then optimize new gas separations membrane systems at the bench scale, including tuning the properties of a novel polyphosphazene polymer in a coating solution and fabricating highly engineered porous hollow fiber supports. The project also sought to define the processes needed to coat the fiber support to manufacture composite hollow fiber membranes with high performance, ultra-thin separation layers. Physical, chemical, and mechanical stability of the materials (individual and composite) towards coal flue gas components was considered via exposure and performance tests. Preliminary design, technoeconomic, and economic feasibility analyses were conducted to evaluate the overall performance and impact of the process on the cost of electricity (COE) for a coal-fired plant including capture technologies. At the onset of the project, Membranes based on coupling a novel selective material polyphosphazene with an engineered hollow fiber support was found to have the potential to capture greater than 90% of the CO2 in flue gas with less than 35% increase in COE, which would achieve the DOE-targeted performance criteria. While lab-scale results for the polyphosphazene materials were very promising, and the material was incorporated into hollow-fiber modules, difficulties were encountered relating to the performance of these membrane systems over time. Performance, as measured by both flux of and selectivity for CO2 over other flue gas constituents was found to deteriorate over time, suggesting a system that was

  10. Development of a novel ceramic microchannel reactor for methane steam reforming

    Science.gov (United States)

    Murphy, Danielle M.

    Microchannel heat exchanger and reactor technology has recently gained interest as an innovative way to improve heat-exchanger efficiency, reduce size and weight, and utilize thermal management capabilities to improve conversion, yield, selectivity, and catalyst life. Among many other possible applications, this technology is suitable for advanced recuperated engines, oxy-fired combustion processes for oxygen separation, gas-cooled nuclear reactors, recuperative heat exchanger and reformer units for solid oxide fuel cell systems, and chemical processing. This work presents the design, fabrication, and performance of novel ceramic microchannel reactors in heat-exchanger and fuel-reforming applications. Although most microchannel devices are made of metal materials, ceramics offer an alternative which enables significantly higher operating temperatures, improved tolerance to harsh chemical environments, and improved adherence of ceramic-based catalyst washcoats. Significant cost savings in materials and manufacturing methods for high-volume manufacturing can also be achieved. High-temperature performance of the ceramic microchannel reactor is measured through non-reactive heat-exchanger experiments within a dedicated test stand. Heat-exchanger effectiveness of up to 88% is experimentally established. After coating catalyst material over half of the reactor layers, use of the ceramic microchannel reactor in methane fuel-processing applications is demonstrated. As a fuel reformer, the ceramic microchannel reactor achieves process intensification by combining heat-exchanger and catalytic-reactor functions to produce syngas. Gas hourly space velocities (GHSV) up to 50,000 hr-1 with methane conversion higher than 85% are achieved. A complete computational fluid dynamics (CFD) model, as well as a geometrically simplified hybrid CFD/chemical kinetics model, is used in conjunction with experimentation to examine heat transfer, fluid flow, and chemical kinetics within the

  11. Steam Reforming of Glycerol for Hydrogen Production over Ni/SiO2 Catalyst

    OpenAIRE

    Sadanandam, G.; Sreelatha, N.; Phanikrishna Sharma, M. V.; Kishta Reddy, S.; B. Srinivas; Venkateswarlu, K.; Krishnudu, T.; Subrahmanyam, M.; Durga Kumari, V.

    2012-01-01

    The performance of Ni/SiO2 catalyst for glycerol reforming has been investigated in fixed-bed reactor using careful tailoring of the operational conditions. In this paper, a commercial Engelhard catalyst has been sized and compared to gas product distribution versus catalyst size, water-to-carbon ratio, and stability of the catalyst system. Ni/SiO2 catalysts of three sizes (2×2, 2×4, and 3×5 mm) are evaluated using glycerol: water mixture at 600°C to produce 2 L H2 g−1 cat h−1. The results in...

  12. Modeling of sorption enhanced steam methane reforming in an adiabatic fixed bed reactor

    OpenAIRE

    Fernández García, José Ramón; Abanades García, Juan Carlos; Murillo Villuendas, Ramón

    2012-01-01

    Sorption enhanced methane reforming (SER), employing a CaO-based solid as a high temperature CO2 sorbent, is generally considered to be a promising route for H2 production. In this paper we present a dynamic pseudo-homogeneous model to describe the operation of a packed bed reactor in which the SER reaction is carried out under adiabatic conditions. This reactor can be implemented according to several process schemes, including a novel Ca/Cu looping process for hydrogen generation with inhere...

  13. THOR steam reforming technology for the treatment of ion exchange resins and more complex wastes such as fuel reprocessing wastes

    International Nuclear Information System (INIS)

    The THOR fluidized bed steam reforming process has been successfully operated for more than 10 years in the United States for the treatment of low- and intermediate-level radioactive wastes generated by commercial nuclear power plants. The principle waste stream that has been treated is ion exchange resins (IER) and Dry Active Waste (DAW), but various liquids, sludges, and solid organic wastes have also been treated. The principle advantages of the THOR process include: (a) high volume reduction on the order of 5:1 to 10:1 for IER and up to 50:1 for high plastic content DAW streams depending on the waste type and waste characteristics, (b) environmentally compliant off-gas emissions, (c) reliable conversion of wastes into mineralized products that are durable and leach-resistant, and (d) no liquid effluents for treatment of most radioactive wastes. Over the past ten years, the THOR process has been adapted for the treatment of more complex wastes including historic defense wastes, reprocessing wastes, and other wastes associated with the fuel cycle. As part of the U.S. Department of Energy (DOE) environmental remediation activities, the THOR dual bed steam reforming process has successfully processed: (a) Idaho National Laboratory (INL) Sodium-Bearing Waste (SBW), (b) Savannah River Tank 48 High Level Waste (HLW), (c) Hanford Low Activity Waste (LAW), and (d) Hanford Waste Treatment Plant Secondary Waste (WTP-SW) liquid slurry simulants. The THOR process has been shown in pilot plant operations to successfully process various simulated liquid, radioactive, nitrate-containing wastes into environmentally safe, leach-resistant, solid mineralized products. These mineralized products incorporate normally soluble ions (e.g. - Na, K, Cs, Tc), sulfates, chloride salts, and fluoride salts into an alkali alumino-silicate mineral matrix that inhibits the leaching of those ions into the environment. The solid mineralized products produced by the THOR process exhibit durability

  14. MINERALIZING, STEAM REFORMING TREATMENT OF HANFORD LOW-ACTIVITY WASTE (a.k.a. INEEL/EXT-05-02526)

    International Nuclear Information System (INIS)

    The U.S. Department of Energy (DOE) documented, in 2002, a plan for accelerating cleanup of the Hanford Site, located in southeastern Washington State, by at least 35 years. A key element of the plan was acceleration of the tank waste program and completion of ''tank waste treatment by 2028 by increasing the capacity of the planned Waste Treatment Plant (WTP) and using supplemental technologies for waste treatment and immobilization''. The plan identified steam reforming technology as a candidate for supplemental treatment of as much as 70% of the low-activity waste (LAW). Mineralizing steam reforming technology, offered by THOR Treatment Technologies, LLC would produce a denitrated, granular mineral waste form using a high-temperature fluidized bed process. A pilot scale demonstration of the technology was completed in a 15-cm-diameter reactor vessel. The pilot scale facility was equipped with a cyclone separator and heated sintered metal filters for particulate removal, a thermal oxidizer for reduced gas species and NOx destruction, and a packed activated carbon bed for residual volatile species capture. The pilot scale equipment is owned by the DOE, but located at the Science and Technology Applications Research (STAR) Center in Idaho Falls, ID. Pilot scale testing was performed August 2-5, 2004. Flowsheet chemistry and operational parameters were defined through a collaborative effort involving Idaho National Engineering and Environmental Laboratory (INEEL), Savannah River National Laboratory (SRNL), and THOR Treatment Technologies personnel. Science Application International Corporation, owners of the STAR Center, personnel performed actual pilot scale operation. The pilot scale test achieved a total of 68.4 hours of cumulative/continuous processing operation before termination in response to a bed de-fluidization condition. 178 kg of LAW surrogate were processed that resulted in 148 kg of solid product, a mass reduction of about 17%. The process achieved

  15. Development of robust Co-based catalysts for the selective H{sub 2}-production by ethanol steam-reforming. The Fe-promoter effect

    Energy Technology Data Exchange (ETDEWEB)

    De la Pena O' Shea, Victor A.; Nafria, Raquel; Ramirez de la Piscina, Pilar; Homs, Narcis [Departament de Quimica Inorganica, Institut de Nanociencia i Nanotecnologia, Universitat de Barcelona, Marti i Franques 1-11, 08028 Barcelona (Spain)

    2008-07-15

    The effect of iron promoter on cobalt-based catalysts, active in the ethanol steam-reforming, was studied. Fe{sub x}Co{sub 3-x}O{sub 4}(0{<=} x{<=}0.60) oxides prepared by co-precipitation and an Fe-doped Co{sub 3}O{sub 4} prepared by wetness impregnation are analysed. The activation process of the oxides under reaction conditions was studied by in situ X-ray diffraction (XRD); the activation depended on the iron content of the oxides. The systems were characterized by means of temperature programmed reduction (TPR), XRD and tested in the ethanol steam-reforming reaction at 623-673 K. An optimal iron loading that gives rise to a high H{sub 2}selectivity and catalyst stability was determined. (author)

  16. Promoting Effect of CeO2 Addition on Activity and Catalytic Stability in Steam Reforming of Methane over Ni/Al2O3

    International Nuclear Information System (INIS)

    Hydrogen production by steam reforming of methane was studied over Ni catalysts supported on CeO2, Al2O3 and CeO2-Al2O3. These catalysts were prepared using the impregnation method and characterized by XRD. The effect of CeO2 promoter on the catalytic performance of Ni/Al2O3 catalyst for methane steam reforming reaction was investigated. In fact, CeO2 had a positive effect on the catalytic activity in this reaction. Experimental results demonstrated that Ni/CeO2-Al2O3 catalyst showed excellent catalytic activity and high reaction performance. In addition, the effects of reaction temperature and metal content on the conversion of CH4 and H2/CO ratio were also investigated. Results indicated that CH4 conversion increased significantly with the increase of the reaction temperature and metal content. (author)

  17. A simplified Probabilistic Safety Assesment of a Steam-Methane Reforming Hydrogen Production Plant coupled to a High-Temperature Gas Cooled Nuclear Reactor

    OpenAIRE

    Nelson Edelstein, Pamela; Flores Flores, Alain; Francois Lacouture, Juan Luis

    2005-01-01

    A Probabilistic Safety Assessment (PSA) is being developed for a steam-methane reforming hydrogen production plant linked to a High-Temperature Gas Cooled Nuclear Reactor (HTGR). This work is based on the Japan Atomic Energy Research Institute’s (JAERI) High Temperature Test Reactor (HTTR) prototype in Japan. This study has two major objectives: calculate the risk to onsite and offsite individuals, and calculate the frequency of different types of damage to the complex. A simplified HAZOP...

  18. High Activity of Ce1-xNixO2-y for H2 Production through Ethanol Steam Reforming: Tuning Catalytic Performance through Metal-Oxide Interactions

    Energy Technology Data Exchange (ETDEWEB)

    G Zhou; L Barrio; S Agnoli; S Senanayake; J Evans; A Kubacka; M Estrella; J Hanson; A Martinez-Arias; et al.

    2011-12-31

    The importance of the oxide: Ce{sub 0.8}Ni{sub 0.2}O{sub 2-y} is an excellent catalyst for ethanol steam reforming. Metal-oxide interactions perturb the electronic properties of the small particles of metallic nickel present in the catalyst under the reaction conditions and thus suppress any methanation activity. The nickel embedded in ceria induces the formation of O vacancies, which facilitate cleavage of the OH bonds in ethanol and water.

  19. Modeling Open-Flow Steam Reforming of Methanol over Cu/ZnO/Al2O3 Catalyst in an Axisymmetric Reactor

    OpenAIRE

    Leonardo Pacheco; Dominique Della-Valle; Olivier Le.Corre; Charbel Habch; Lemenand , Thierry; Hassan Peerhossaini

    2015-01-01

    This paper describes a CFD study of the steam-reforming process (SRP) of methanol in a short pseudo-contact time reactor of fixed bed type, in axi-symmetric conditions. The SRP is important sake for hydrogen production, and the design /scale-up/control of the industrial processes in the future are supported by a reliable knowledge and prediction of the catalytic reaction. The difficulty of determining the reaction scheme and the associated constants is wellknown, due to the necess...

  20. On the Solution of the Pellet- and Reactor Model for the Steam Methane Reforming Process Using the Methods of Weighted Residuals

    OpenAIRE

    Tangen, Stian

    2012-01-01

    The purpose of the thesis is to prove that the mole based formulation of a pellet model simulating the steam methane reforming reaction is identical to the novel mass based formulation. To prove this, the numerical methods of orthogonal collocation and least squares will be used. These numerical methods will also be examined to ensure that no numerical differences occur because of the numerical method used. The different formulations were proven identical for the Maxwell-Stefan and the d...

  1. Life cycle inventory analysis of hydrogen production by the steam-reforming process: comparison between vegetable oils and fossil fuels as feedstock

    International Nuclear Information System (INIS)

    A life cycle inventory analysis has been conducted to assess the environmental load, specifically CO2 (fossil) emissions and global warming potential (GWP), associated to the production of hydrogen by the steam reforming of hydrocarbon feedstocks (methane and naphtha) and vegetable oils (rapeseed oil, soybean oil and palm oil). Results show that the GWPs associated with the production of hydrogen by steam reforming in a 100 years time frame are 9.71 and 9.46 kg CO2-equivalent/kg H2 for natural gas and naphtha, respectively. For vegetable oils, the GWP decreases to 6.42 kg CO2-equivalent/kg H2 for rapeseed oil, 4.32 for palm oil and 3.30 for soybean oil. A dominance analysis determined that the part of the process that has the largest effect on the GWP is the steam reforming reaction itself for the fossil fuel-based systems, which accounts for 56.7% and 74% of the total GWP for natural gas and naphtha, respectively. This contribution is zero for vegetable oil-based systems, for which harvesting and oil production are the main sources of CO2-eq emissions.(author)

  2. Draft, development and optimization of a fuel cell system for residential power generation with steam reformer; Entwurf, Aufbau und Optimierung eines PEM-Brennstoffzellensystems zur Hausenergieversorgung mit Dampfreformer

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, H.

    2006-05-17

    The first development cycle of a residential power generation system is described. A steam reformer was chosen to produce hydrogen out of natural gas. After carbon monoxide purification with a preferential oxidation (PrOx) unit the hydrogen rich reformat gas is feed to the anode of the PEM-fuel cell, where due to the internal reaction with air oxygen form the cathode side water, heat and electricity is produced. Due to an incomplete conversion the anode off gas contains hydrogen and residual methane, which is feed to the burner of the steam reformer to reduce the needed amount of external fuel to heat the steam reformer. To develop the system the components are separately investigated and optimized in their construction or operation to meet the system requirements. After steady state and dynamic characterization of the components they were coupled one after another to build the system. To operate the system a system control was developed to operate and characterize this complex system. After characterization the system was analyzed for further optimization. During the development of the system inventions like a water cooled PrOx, an independent fuel cell controller or a burner for anodic off gas recirculation were made. The work gives a look into the interactions between the components and allows to understand the problems by coupling such components. (orig.)

  3. Numerical analysis of hydrogen production via methane steam reforming in porous media solar thermochemical reactor using concentrated solar irradiation as heat source

    International Nuclear Information System (INIS)

    Highlights: • H2 production by hybrid solar energy and methane steam reforming is analyzed. • MCRT and FVM coupling method is used for chemical reaction in solar porous reactor. • LTNE model is used to study the solid phase and fluid phase thermal performance. • Modified P1 approximation programmed by UDFs is used for irradiative heat transfer. - Abstract: The calorific value of syngas can be greatly upgraded during the methane steam reforming process by using concentrated solar energy as heat source. In this study, the Monte Carlo Ray Tracing (MCRT) and Finite Volume Method (FVM) coupling method is developed to investigate the hydrogen production performance via methane steam reforming in porous media solar thermochemical reactor which includes the mass, momentum, energy and irradiative transfer equations as well as chemical reaction kinetics. The local thermal non-equilibrium (LTNE) model is used to provide more temperature information. The modified P1 approximation is adopted for solving the irradiative heat transfer equation. The MCRT method is used to calculate the sunlight concentration and transmission problems. The fluid phase energy equation and transport equations are solved by Fluent software. The solid phase energy equation, irradiative transfer equation and chemical reaction kinetics are programmed by user defined functions (UDFs). The numerical results indicate that concentrated solar irradiation on the fluid entrance surface of solar chemical reactor is highly uneven, and temperature distribution has significant influence on hydrogen production

  4. Hydrogen generation from steam reforming of ethanol in dielectric barrier discharge

    Institute of Scientific and Technical Information of China (English)

    Baowei Wang; Yijun Lü; Xu Zhang; Shuanghui Hu

    2011-01-01

    Dielectric barrier discharge(DBD)was used for the generation of hydrogen from ethanol reforming.Effects of reaction conditions,such as vaporization temperature,ethanol flow rate,water/ethanol ratio,and addition of oxygen,on the ethanol conversion and hydrogen yield,were studied.The results showed that the increase of ethanol flow rate decreased ethanol conversion and hydrogen yield,and high water/ethanol ratio and addition of oxygen were advantageous.Ethanol conversion and hydrogen yield increased with the vaporization room temperature up to the maximum at first,and then decreased slightly.The maximum hydrogen yield of 31.8% was obtained at an ethanol conversion of 88.4% under the optimum operation conditions of vaporization room temperature of 120℃,ethanol flux of 0.18 mL/min,water/ethanol ratio of 7.7 and oxygen volume concentration of 13.3%.

  5. Analysis and Simulation of Severe Accidents in a Steam Methane Reforming Plant

    Directory of Open Access Journals (Sweden)

    MohammadJavad Jafari

    2015-10-01

    Full Text Available Severe accidents of process industries in Iran have increased significantly in recent decade. This study quantitatively analyzes the hazards of severe accidents imposed on people, equipment and building by a hydrogen production facility. A hazard identification method was applied. Then a consequence simulation was carried out using PHAST 6.54 software package and at the end, consequence evaluation was carried out based on the best-known and different criteria. Most hazardous jet fire and flash fire will be occurred in desulfurization and reformer units respectively. The most dangerous vapor cloud explosion will be caused by a rupture in desorfurizing reactor. This incident with an overpressure of 0.83 bars at a distance of 45 m will kill all people and will destroy all buildings and equipments that are located at this distance. The safety distance determined by TNO Multi-Energy model and according to the worst consequence is equal to 260 m. Vapor cloud explosion will have the longest harmful distance on both human and equipment compared to jet fire and flash fire. Atmospheric condition will have a significant influence on harmful distance, especially in vapor cloud explosion. Therefore, the hydrogen production by natural  gas  reforming  is  a  high-risk  process  and  should  always  be  accompanied  by  the  full implementation of the safety rules, personal protection and equipment fireproofing and building blast proofing against jet fire and explosions.

  6. Secondary Waste Form Screening Test Results - THOR(regsign) Fluidized Bed Steam Reforming Product in a Geopolymer Matrix

    International Nuclear Information System (INIS)

    Screening tests are being conducted to evaluate waste forms for immobilizing secondary liquid wastes from the Hanford Tank Waste Treatment and Immobilization Plant (WTP). Plans are underway to add a stabilization treatment unit to the Effluent Treatment Facility to provide the needed capacity for treating these wastes from WTP. The current baseline is to use a Cast Stone cementitious waste form to solidify the wastes. Through a literature survey, DuraLith alkali-aluminosilicate geopolymer, fluidized-bed steam reformation (FBSR) granular product encapsulated in a geopolymer matrix, and a Ceramicrete phosphate-bonded ceramic were identified both as candidate waste forms and alternatives to the baseline. These waste forms have been shown to meet waste disposal acceptance criteria, including compressive strength and universal treatment standards for Resource Conservation and Recovery Act (RCRA) metals (as measured by the toxicity characteristic leaching procedure (TCLP)). Thus, these non-cementitious waste forms should also be acceptable for land disposal. Information is needed on all four waste forms with respect to their capability to minimize the release of technetium. Technetium is a radionuclide predicted to be in the secondary liquid wastes in small quantities, but the Integrated Disposal Facility (IDF) risk assessment analyses show that technetium, even at low mass, produces the largest contribution to the estimated IDF disposal impacts to groundwater.

  7. Optimization of Hydrogen Production by Ethanol Steam Reforming Using Maximization of H2/CO Ratio with Taguchi Experimental Design Method

    Directory of Open Access Journals (Sweden)

    Ali Eliassi

    2013-01-01

    Full Text Available In this study the effects of some different factors on ceria (CeO2 catalytic activity for ethanol steam reforming (ESR to produce high H2/CO ratio were investigated. The considered factors were sonication time in three durations (0, 15 and 30 minutes, calcination temperature at three temperatures (500, 650 and 800°C, mole ratio of H2O/ethanol in three ratios (3, 5 and 8 and reactor temperature at three temperatures (300, 350 and 400°C. The Taguchi L9 experimental design method was used to investigate the effect of these parameters on maximization of H2/CO. To identify the catalyst characteristics XRD, SEM, EDS, BET and TGA analysis were done. It was established that a face centered cubic crystal forms of nano particles of CeO2 were formed. Also the obtained results showed that by increasing calcination temperature or reducing the sonication time, the nano particle size was increased. The reactor tests showed that the optimum conditions for maximization of H2/CO ratio were: sonication time zero, calcination temperature 800°C, H2O/ethanol ratio 3 and reactor temperature 300°C. The mole percent of H2 and CO in these conditions were 64.46 and 0.011%, respectively.

  8. Valorisation of Vietnamese Rice Straw Waste: Catalytic Aqueous Phase Reforming of Hydrolysate from Steam Explosion to Platform Chemicals

    Directory of Open Access Journals (Sweden)

    Cao Huong Giang

    2014-12-01

    Full Text Available A family of tungstated zirconia solid acid catalysts were synthesised via wet impregnation and subsequent thermochemical processing for the transformation of glucose to 5-hydroxymethylfurfural (HMF. Acid strength increased with tungsten loading and calcination temperature, associated with stabilisation of tetragonal zirconia. High tungsten dispersions of between 2 and 7 W atoms·nm−2 were obtained in all cases, equating to sub-monolayer coverages. Glucose isomerisation and subsequent dehydration via fructose to HMF increased with W loading and calcination temperature up to 600 °C, indicating that glucose conversion to fructose was favoured over weak Lewis acid and/or base sites associated with the zirconia support, while fructose dehydration and HMF formation was favoured over Brönsted acidic WOx clusters. Aqueous phase reforming of steam exploded rice straw hydrolysate and condensate was explored heterogeneously for the first time over a 10 wt% WZ catalyst, resulting in excellent HMF yields as high as 15% under mild reaction conditions.

  9. Secondary Waste Form Screening Test Results—THOR® Fluidized Bed Steam Reforming Product in a Geopolymer Matrix

    Energy Technology Data Exchange (ETDEWEB)

    Pires, Richard P.; Westsik, Joseph H.; Serne, R. Jeffrey; Mattigod, Shas V.; Golovich, Elizabeth C.; Valenta, Michelle M.; Parker, Kent E.

    2011-07-14

    Screening tests are being conducted to evaluate waste forms for immobilizing secondary liquid wastes from the Hanford Tank Waste Treatment and Immobilization Plant (WTP). Plans are underway to add a stabilization treatment unit to the Effluent Treatment Facility to provide the needed capacity for treating these wastes from WTP. The current baseline is to use a Cast Stone cementitious waste form to solidify the wastes. Through a literature survey, DuraLith alkali-aluminosilicate geopolymer, fluidized-bed steam reformation (FBSR) granular product encapsulated in a geopolymer matrix, and a Ceramicrete phosphate-bonded ceramic were identified both as candidate waste forms and alternatives to the baseline. These waste forms have been shown to meet waste disposal acceptance criteria, including compressive strength and universal treatment standards for Resource Conservation and Recovery Act (RCRA) metals (as measured by the toxicity characteristic leaching procedure [TCLP]). Thus, these non-cementitious waste forms should also be acceptable for land disposal. Information is needed on all four waste forms with respect to their capability to minimize the release of technetium. Technetium is a radionuclide predicted to be in the secondary liquid wastes in small quantities, but the Integrated Disposal Facility (IDF) risk assessment analyses show that technetium, even at low mass, produces the largest contribution to the estimated IDF disposal impacts to groundwater.

  10. Hydrogen production from steam methane reforming and electrolysis as part of a near-term hydrogen infrastructure

    International Nuclear Information System (INIS)

    Building a complete hydrogen infrastructure for a transportation system based on Fuel Cells (FC) and hydrogen is a risky and expensive ordeal, especially given that it is not known with complete certainty that Fuel Cells will indeed replace the gasoline ICE. But how can we expect the diffusion of an automotive technology if there is no infrastructure to support its fuel needs? This gives rise to a chicken and egg type problem. One way to get around this problem is to produce hydrogen when and where it is needed. This solves the problems of high costs associated with expensive pipeline distribution networks, the high energy-intensities associated with liquefaction of hydrogen and the high costs of cryogenic equipment. This paper will consider the advantages and disadvantages of two such hydrogen production mechanisms, namely, onsite production of hydrogen from Electrolysis and onsite production of hydrogen from Steam Methane Reforming (SMR). Although SMR hydrogen may be more economical due to the availability and low cost of methane, under certain market and technological conditions onsite electrolytic hydrogen can be more attractive. The paper analyses the final price of delivered hydrogen based on its sensitivity to market conditions and technology developments. (author)

  11. Thermodynamic Investigation of Hydrogen Production by Methane Steam Reforming using Integrated Hydrogen-permselective Membrane Reactor with CO2 absorption

    International Nuclear Information System (INIS)

    The role of hydrogen as an energy carrier became more important to the future energy system. Methane steam reforming (MSR) is one of the most important chemical processes in hydrogen production. To improve the conversion of methane to hydrogen, a hydrogen-permselective membrane reactor with a carbon dioxide absorbent was proposed and investigated. The conversion at 893 K in the integrated reactor with CaO as absorbent was almost equal to that at above 1000 K in the conventional reactor. Exergy analyses indicated that the a large portion of exergy loss for hydrogen production was chemical exergy loss in the case without methane recycle, while thermal exergy loss in the case with recycle use. The exergy loss of this process using the hydrogen-permselective membrane reactor with the CaO-absorbent was estimated about 70% of that by the conventional catalytic reactor. Efficiencies of the integrated reactor process, based on the energy and exergy losses were compared with those of other hydrogen production processes. (authors)

  12. Application of multisection packing concept to sorption-enhanced steam methane reforming reaction for high-purity hydrogen production

    Science.gov (United States)

    Lee, Chan Hyun; Mun, Sungyong; Lee, Ki Bong

    2015-05-01

    Hydrogen has been gaining popularity as a new clean energy carrier, and bulk hydrogen production is achieved through the steam methane reforming (SMR) reaction. Since hydrogen produced via the SMR reaction contains large amounts of impurities such as unreacted reactants and byproducts, additional purification steps are needed to produce high-purity hydrogen. By applying the sorption-enhanced reaction (SER), in which catalytic reaction and CO2 byproduct removal are carried out simultaneously in a single reactor, high-purity hydrogen can be directly produced. Additionally, the thermodynamic limitation of conventional SMR reaction is circumvented, and the SMR reaction process becomes simplified. To improve the performance of the SER, a multisection packing concept was recently proposed. In this study, the multisection packing concept is experimentally demonstrated by applying it to a sorption-enhanced SMR (SE-SMR) reaction. The experimental results show that the SE-SMR reaction is significantly influenced by the reaction temperature, owing to the conflicting dependence of the reaction rate and the CO2 sorption uptake on the reaction temperature. Additionally, it is confirmed that more high-purity hydrogen (<10 ppm of CO) can be produced by applying the multisection packing concept to the SE-SMR reactions operated at sufficiently high temperatures where the SMR reaction is not limited by rate.

  13. Economic analysis of hydrogen production through a bio-ethanol steam reforming process: Sensitivity analyses and cost estimations

    International Nuclear Information System (INIS)

    In this study, the hydrogen selling price from ethanol steam reforming has been estimated for two different production scenarios in the United States, i.e. central production (150,000 kg H2/day) and distributed (forecourt) production (1500 kg H2/day), based on a process flowchart generated by Aspen Plus registered including downstream purification steps and economic analysis model template published by the U.S Department of Energy (DOE). The effect of several processing parameters as well as catalyst properties on the hydrogen selling price has been evaluated. 2.69/kg is estimated as the selling price for a central production process of 150,000 kg H2/day and 4.27/kg for a distributed hydrogen production process at a scale of 1500 kg H2/day. Among the parameters investigated through sensitivity analyses, ethanol feedstock cost, catalyst cost, and catalytic performance are found to play a significant role on determining the final hydrogen selling price. (author)

  14. Catalytic multi-stage liquefaction of coal at HTI: Bench-scale studies in coal/waste plastics coprocessing

    Energy Technology Data Exchange (ETDEWEB)

    Pradhan, V.R.; Lee, L.K.; Stalzer, R.H. [Hydrocarbon Technologies, Inc., Lawrenceville, NJ (United States)] [and others

    1995-12-31

    The development of Catalytic Multi-Stage Liquefaction (CMSL) at HTI has focused on both bituminous and sub-bituminous coals using laboratory, bench and PDU scale operations. The crude oil equivalent cost of liquid fuels from coal has been curtailed to about $30 per barrel, thus achieving over 30% reduction in the price that was evaluated for the liquefaction technologies demonstrated in the late seventies and early eighties. Contrary to the common belief, the new generation of catalytic multistage coal liquefaction process is environmentally very benign and can produce clean, premium distillates with a very low (<10ppm) heteroatoms content. The HTI Staff has been involved over the years in process development and has made significant improvements in the CMSL processing of coals. A 24 month program (extended to September 30, 1995) to study novel concepts, using a continuous bench scale Catalytic Multi-Stage unit (30kg coal/day), has been initiated since December, 1992. This program consists of ten bench-scale operations supported by Laboratory Studies, Modelling, Process Simulation and Economic Assessments. The Catalytic Multi-Stage Liquefaction is a continuation of the second generation yields using a low/high temperature approach. This paper covers work performed between October 1994- August 1995, especially results obtained from the microautoclave support activities and the bench-scale operations for runs CMSL-08 and CMSL-09, during which, coal and the plastic components for municipal solid wastes (MSW) such as high density polyethylene (HDPE)m, polypropylene (PP), polystyrene (PS), and polythylene terphthlate (PET) were coprocessed.

  15. A Phenomenological Study on the Synergistic Role of Precious Metals in the Steam Reforming of Logistic Fuels on Trimetal-Supported Catalysts

    Directory of Open Access Journals (Sweden)

    Abdul-Majeed Azad

    2010-01-01

    Full Text Available Fuel processors are required to convert sulfur-laden logistic fuels (jet fuels, diesel, and coal into fuel cell quality hydrogen-rich reformate with little or no sulfur for extended periods. Sulfur poisons and deactivates the reforming catalyst, therefore, sulfur-tolerant catalysts ought to be developed. In this paper, the development, characterization, and evaluation of a series of nanoscale ceria-supported reforming catalysts containing three noble metals in low concentration (1 wt% ≤ total metal loading ≤ 1.33 wt% for the steam-reforming of kerosene (a JP-8 surrogate are reported. Their performance is quantified in terms of H2 yield, tolerance towards sulfur in the fuel, and the on-stream stability and compared with that of monometal and bimetal analogs under identical conditions. Due to the inherent cooperative synergy, a trimetal catalyst was found far superior to its mono- and bimetallic analog containing same amount of the precious metal loading in terms of quality of the reformate (measured by H2 level in steady-state as well as the catalyst longevity on-stream prior to deactivation. At the same time a mechanistic correlation between the distinct role of a given precious metal and the extent of its loading in each of the formulations and quality of the corresponding desulfurized H2-rich reformate was discovered.

  16. Studying the characteristics of a 5 kW power installation on solid-oxide fuel cells with steam reforming of natural gas

    Science.gov (United States)

    Munts, V. A.; Volkova, Yu. V.; Plotnikov, N. S.; Dubinin, A. M.; Tuponogov, V. G.; Chernishev, V. A.

    2015-11-01

    The results from tests of a 5 kW power plant on solid-oxide fuel cells (SOFCs), in which natural gas is used as fuel, are presented. The installation's process circuit, the test procedure, and the analysis of the obtained results are described. The characteristics of the power plant developed by the Ural Industrial Company are investigated in four steady-state modes of its operation: with the SOFC nominal power capacity utilized by 40% (2 kW), 60% (3 kW), 90% (4.5 kW) and 110% (5.4 kW) (the peaking mode). The electrical and thermodynamic efficiencies are calculated for all operating modes, and the most efficient mode, in which the electrical efficiency reached almost 70%, is determined. The air excess coefficient and heat loss with flue gases q 2 are determined, and it is revealed that the heat loss q 5 decreases from 40 to 25% with increasing the load. Thermal balances are drawn up for the following components of the system the reformer, the SOFC battery, the catalytic burner for afterburning anode gases, the heat exchanger for heating the cathode air and the mixture of natural gas and steam, and the actual fuel utilization rates in the electrochemical generator are calculated. An equation for the resulting natural gas steam reforming reaction was obtained based on the results from calculating the equilibrium composition of reforming products for the achieved temperatures at the reformer outlet t 3.

  17. A novel bench-scale column assay to investigate site-specific nitrification biokinetics in biological rapid sand filters

    DEFF Research Database (Denmark)

    Tatari, Karolina; Smets, Barth F.; Albrechtsen, Hans-Jørgen

    2013-01-01

    A bench-scale assay was developed to obtain site-specific nitrification biokinetic information from biological rapid sand filters employed in groundwater treatment. The experimental set-up uses granular material subsampled from a full-scale filter, packed in a column, and operated with controlled....../m3 packed sand/h could easily be determined at 7.5 g NH4+–N/m3 packed sand/h. This assay, with conditions reflecting full-scale observations, and where the biological activity is subject to minimal physical disturbance, provides a simple and fast, yet powerful tool to gain insight in nitrification...

  18. Steam reforming of bio-ethanol over Ni on Ce-ZrO2 support: Influence of redox properties on the catalyst reactivity

    Directory of Open Access Journals (Sweden)

    Sumittra Charojrochkul

    2006-11-01

    Full Text Available The steam reforming of ethanol over Ni on Ce-ZrO2 support, (Ni/ Ce-ZrO2 were studied. The catalyst provides significantly higher reforming reactivity and excellent resistance toward carbon deposition compared to Ni/Al2O3 under the same conditions. At the temperature above 800ºC, the main products from the reforming processes over Ni/Ce-ZrO2 were H2, CO, and CO2 with small amount of CH4 depending on the inlet ethanol/steam and oxygen/ethanol ratios, whereas high hydrocarbon compounds i.e., C2H4 and C2H6 were also observed from the reforming of ethanol over Ni/Al2O3 in the range of conditions studied (700- 1000ºC.These excellent ethanol reforming performances of Ni/Ce-ZrO2 in terms of stability, reactivity and product selectivities are due to the high redox property of Ce-ZrO2. During the ethanol reforming process, in addition to the reactions on Ni surface, the gas-solid reactions between the gaseous components presented in the system (C2H5OH, C2H6, C2H4, CH4, CO2, CO, H2O, and H2 and the lattice oxygen (Ox on Ce-ZrO2 surface also take place. Among these redox reactions, the reactions of adsorbed surface hydrocarbons with the lattice oxygen (Ox (CnHm + Ox → nCO + m/2(H2 + Ox-n can eliminate the formation of high hydrocarbons (C2H6 and C2H4, which easily decompose and form carbon species on Ni surface (CnHm→ nC + m/2H2.

  19. The Effect of Fe in Perovskite Catalysts for Steam CO2 Reforming of Methane.

    Science.gov (United States)

    Yang, Eun-Hyeok; Noh, Young-Su; Lim, Sung Soo; Ahn, Byoung Sung; Moon, Dong Ju

    2016-02-01

    In this work, La0.95Sr0.05Ni(1-x)Fe(x)O3 catalysts were prepared by modified EDTA-cellulose method and the catalysts were characterized by various techniques such as N2 physisorption, TPR, XRD, SEM, TEM-EDS and TG analysis. La00.95Sr0.05Ni0.5Fe0.5O3 catalyst showed better catalytic performance under the reaction conditions of 900 degrees C, 21 bar and feed molar ratio of CH4:CO2:H20 = 1:0.7:1.5. It is considered that the dilution effect on nickel prevented the formation of large monometallic ensembles that favour the carbon deposition in reforming reactions, and the mean metallic particle size of Ni decreased with increasing substitution rate in B site. Therefore, partial substitution of Fe in B site enhances the dilution effect and induces a reaction between CO2 and La2O3, thereby resisting the carbon deposition and increasing CO2 conversion. PMID:27433705

  20. Effect of Sludge Recycle Ratio for Improvement of Sewage Treatment, in Ghaemshahr Textile Plant, a Bench Scale Model

    Directory of Open Access Journals (Sweden)

    M. Sadeghpour

    2010-01-01

    Full Text Available The purpose of present study was to demonstrate the effect of return sludge ratio which was influenced the treatability of municipal wastewater. The fresh wastewater with identified composition was collected from the influent of a domestic plant, Ghemshar, Iran. To demonstrate the use of activated sludge process in domestic wastewater treatment plant, a bench- scale aerobic digestion tank was used for bench-scale experimental model. A cubical aeration tank and sedimentation tank was fabricated from plexi-glass. Fresh wastewater was introduced into the aerated tank and then the effluent was settled in a settling basin. Some proportional of the aged sludge was recycled to the aeration tank in order to enhance the wastewater treatment. In this experiment, results showed that 8 h hydraulic retention times (HRT was the suitable operational parameters. In this system, pH range, DO and temperature were 7.5 to 8.5, 4-6 mg/l and 22-25 C, respectively. COD removal was directly related to sludge recycle ratio. By increasing return sludge from 2.5 to 40 percent, the COD removal was increased from 70 to 95 percent. Kinetic parameters and kinetic model for COD removal of biological activated sludge system were determined.

  1. Bench scale studies: Ozonation as a potential treatment for waters contaminated with hydrocarbons or dioxins and furans

    International Nuclear Information System (INIS)

    The objective of the bench scale studies was to examine the destruction efficiency and efficacy of ozone on chemicals of concern (COC's) commonly found in contaminated ground water and rhenoformer wash water. The ground water used in these tests contained aromatic petroleum hydrocarbons, chlorinated hydrocarbons, and mineral spirits. The rhenoformer wash water used in these tests contained a variety of dioxins (including 2,3,7,8-tetrachlorodibenzo-p-dioxin) and furans. Summaries are presented of the bench scale studies by describing the COCs, methodologies, test reactors, observations, and results. The summaries also detail which applications hold promise with respect to ozonation and which ones do not. Bench test results for the experiments in which aromatic petroleum hydrocarbons, chlorinated hydrocarbons, and mineral spirits where the COCs were relatively successful. Concentrations for the COCs ranging from 300 to 3,400 micrograms per liter (microg/L) were brought below levels specified for storm sewer discharge per the National Priority Discharge Elimination Systems (NPDES) permit requirements. Bench test results for the experiments in which dioxins and furans were the COCs were less promising and revealed that additional processes would have to be used in conjunction with ozonation to bring the concentration of COCs within the targeted ranges. It was realized, however, that the effectiveness and efficacy of ozonation were diminished by the presence of particulates, to which some of the dioxin and furan compounds adhered

  2. 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.

  3. Développement d'un réacteur microstructuré basé sur des filaments métalliques catalytiques: production autotherme d'hydrogène par steam-reforming oxydatif du méthanol

    OpenAIRE

    Horny, Chrystèle; Renken, Albert

    2007-01-01

    The aim of this work is to develop a microstructured reactor based on filamentous catalysts for the Oxidative Steam-Reforming of Methanol (OSRM), to produce hydrogen as feed for a fuel cell, in an autothermal way. Hydrogen is produced by the methanol Steam-Reforming (SR) reaction. This endothermic reaction requires an external heat source which is, in our case, generated by methanol oxidation. The coupling of these two reactions – SR and oxidation, called oxidative steam-reforming of methanol...

  4. Développement d'un réacteur microstructuré basé sur des filaments métalliques catalytiques: production autotherme d'hydrogène par steam-reforming oxydatif du méthanol

    OpenAIRE

    Horny, Chrystèle

    2005-01-01

    The aim of this work is to develop a microstructured reactor based on filamentous catalysts for the Oxidative Steam-Reforming of Methanol (OSRM), to produce hydrogen as feed for a fuel cell, in an autothermal way. Hydrogen is produced by the methanol Steam-Reforming (SR) reaction. This endothermic reaction requires an external heat source which is, in our case, generated by methanol oxidation. The coupling of these two reactions – SR and oxidation, called oxidative steam-reforming of methanol...

  5. Radioactive Demonstrations Of Fluidized Bed Steam Reforming As A Supplementary Treatment For Hanford's Low Activity Waste And Secondary Wastes

    International Nuclear Information System (INIS)

    The U.S. Department of Energy's Office of River Protection (ORP) is responsible for the retrieval, treatment, immobilization, and disposal of Hanford's tank waste. Currently there are approximately 56 million gallons of highly radioactive mixed wastes awaiting treatment. A key aspect of the River Protection Project (RPP) cleanup mission is to construct and operate the Waste Treatment and Immobilization Plant (WTP). The WTP will separate the tank waste into high-level and low-activity waste (LAW) fractions, both of which will subsequently be vitrified. The projected throughput capacity of the WTP LAW Vitrification Facility is insufficient to complete the RPP mission in the time frame required by the Hanford Federal Facility Agreement and Consent Order, also known as the Tri-Party Agreement (TPA), i.e. December 31, 2047. Therefore, Supplemental Treatment is required both to meet the TPA treatment requirements as well as to more cost effectively complete the tank waste treatment mission. The Supplemental Treatment chosen will immobilize that portion of the retrieved LAW that is not sent to the WTP's LAW Vitrification facility into a solidified waste form. The solidified waste will then be disposed on the Hanford site in the Integrated Disposal Facility (IDF). In addition, the WTP LAW vitrification facility off-gas condensate known as WTP Secondary Waste (WTP-SW) will be generated and enriched in volatile components such as Cs-137, I-129, Tc-99, Cl, F, and SO4 that volatilize at the vitrification temperature of 1150 C in the absence of a continuous cold cap. The current waste disposal path for the WTP-SW is to recycle it to the supplemental LAW treatment to avoid a large steady state accumulation in the pretreatment-vitrification loop. Fluidized Bed Steam Reforming (FBSR) offers a moderate temperature (700-750 C) continuous method by which LAW and/or WTP-SW wastes can be processed irrespective of whether they contain organics, nitrates, sulfates/sulfides, chlorides

  6. A Phenomenological Study on the Synergistic Role of Precious Metals in the Steam Reforming of Logistic Fuels on Bimetal-Supported Catalysts

    Directory of Open Access Journals (Sweden)

    Abdul-Majeed Azad

    2011-01-01

    Full Text Available Fuel processors are required to convert sulfur-laden logistic fuels into hydrogen-rich reformate and deliver to the fuel cell stack with little or no sulfur. Since sulfur poisons and deactivates the reforming catalyst, robust sulfur-tolerant catalysts ought to be developed. In this paper, the development, characterization and evaluation of a series of reforming catalysts containing two noble metals (with total metal loading not exceeding 1 weight percent supported on nanoscale ceria for the steam-reforming of kerosene is reported. Due to inherent synergy, a bimetallic catalyst is superior to its monometallic analog, for the same level of loading. The choice of noble metal combination in the bimetallic formulations plays a vital and meaningful role in their performance. Presence of ruthenium and/or rhodium in formulations containing palladium showed improved sulfur tolerance and significant enhancement in their catalytic activity and stability. Rhodium was responsible for higher hydrogen yields in the logistic fuel reformate. Duration of steady hydrogen production was higher in the case of RhPd (75 h than for RuPd (68 h; hydrogen generation was stable over the longest period (88 h with RuRh containing no Pd. A mechanistic correlation between the characteristic role of precious metals in the presence of each other is discussed.

  7. Steam Reforming of Fast Pyrolysis-Derived Aqueous Phase Oxygenates over Co, Ni, and Rh Metals Supported on MgAl2O4

    Energy Technology Data Exchange (ETDEWEB)

    Xing, Rong; Lebarbier, Vanessa M.; Flake, Matthew D.; Kovarik, Libor; Albrecht, Karl O.; Deshmane, Chinmay A.; Dagle, Robert A.

    2016-04-03

    In this study we examine feasibility for steam reforming the mixed oxygenate aqueous fraction derived from mildly hydrotreated fast pyrolysis bio-oils. Catalysts selective towards hydrogen formation and resistant to carbon formation utilizing feeds with relatively low steam-to-carbon (S/C) ratios are desired. Rh (5 wt%), Pt (5 wt%), Ru (5 wt%), Ir (5 wt%), Ni (15 wt%), and Co (15 wt%) metals supported on MgAl2O4 were evaluated for catalytic performance at 500˚C and 1 atm using a complex feed mixture comprising of acids, polyols, cycloalkanes, and phenolic compounds. The Rh catalyst was found to be the most active and resistant to carbon formation. The Ni and Co catalysts were found to be more active than the other noble metal catalysts investigated (Pt, Ru, and Ir). However, Ni was found to form significantly more carbon (coke) on the catalyst surface. Furthermore, Co was found to be the most selective towards H2 formation. Evaluating the effect of temperature on stability for the Rh catalyst we found that catalyst stability was best when operated at 500˚C as compared to the higher temperatures investigated (700, 800˚C). When operating at 700˚C significantly more graphitic formation was observed on the spent catalyst surface. Operating at 800˚C resulted in reactor plugging as a result of thermal decomposition of the reactants. Thus, a concept analogous to the petroleum industries’ use of a pre-reformer, operated at approximately 500˚C for steam reforming of the heavier naphtha components, followed by a high temperature methane reforming operated in the 600-850˚C temperature range, could be applied in the case of steam reforming biomass derived oxygenates. Moreover, stability evaluations were performed over the Rh, Ni, and Co catalysts at 500˚C and 1 atm, under similar initial conversions, reveal the Co catalyst to be the most stable and selective towards H2 production. Conversion and selectivity to CH4 over Co remained relatively stable at approximately

  8. Hydrogen production from raw bioethanol steam reforming: Optimization of catalyst composition with improved stability against various impurities

    Energy Technology Data Exchange (ETDEWEB)

    Le Valant, Anthony; Can, Fabien; Bion, Nicolas; Duprez, Daniel; Epron, Florence [Laboratoire de Catalyse en Chimie organique, UMR6503 CNRS, Universite de Poitiers, 40 avenue du recteur Pineau, 86022 Poitiers Cedex (France)

    2010-05-15

    The use of raw bioethanol is of major importance for a cost effective industrial application. Raw bioethanol contains higher alcohols as the main impurities and also aldehydes, amines, acids and esters. The effect of these impurities on the catalytic performances for ethanol steam reforming (ESR) has been studied, using a reference catalyst, Rh/MgAl{sub 2}O{sub 4}. It was shown that the aldehyde, the amine and methanol have no negative effect on the catalytic performances, contrary to the ester, acid and higher alcohols. The deactivation is mainly explained by coke formation favored by the presence of these impurities in the feed. In order to improve the stability of the catalyst and its performances in the presence of these deactivating impurities, the catalyst formulation, i.e. the composition of the support and of the metallic phase, was modified. The addition of rare earth elements instead of magnesium to the alumina support leads to a decrease of the strong and medium acid sites and to an increase of the basicity. On these modified supports, the dehydration reaction, leading to olefins, which are coke precursors, is disfavored, the ethanol conversion and the hydrogen yield are increased. The best catalytic performances were obtained with Rh/Y-Al{sub 2}O{sub 3}. Then, the metallic phase was also modified by adding a second metal (Ni, Pt or Pd). The Rh-Ni/Y-Al{sub 2}O{sub 3} catalyst leads to the highest hydrogen yield. This catalyst, tested in the presence of raw bioethanol during 24 h was very stable compared to the reference catalyst Rh/MgAl{sub 2}O{sub 4}, which was strongly deactivated after 2 h of time-on -stream. (author)

  9. RADIOACTIVE DEMONSTRATIONS OF FLUIDIZED BED STEAM REFORMING WITH ACUTAL HANFORD LOW ACTIVITY WASTES VERIFYING FBSR AS A SUPPLEMENTARY TREATMENT

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C.; Crawford, C.; Burket, P.; Bannochie, C.; Daniel, G.; Nash, C.; Cozzi, A.; Herman, C.

    2012-01-12

    The U.S. Department of Energy's Office of River Protection is responsible for the retrieval, treatment, immobilization, and disposal of Hanford's tank waste. Currently there are approximately 56 million gallons of highly radioactive mixed wastes awaiting treatment. A key aspect of the River Protection Project cleanup mission is to construct and operate the Waste Treatment and Immobilization Plant (WTP). The WTP will separate the tank waste into high-level waste (HLW) and low-activity waste (LAW) fractions, both of which will subsequently be vitrified. The projected throughput capacity of the WTP LAW Vitrification Facility is insufficient to complete the cleanup mission in the time frame required by the Hanford Federal Facility Agreement and Consent Order, also known as the Tri-Party Agreement (TPA). Therefore, Supplemental Treatment is required both to meet the TPA treatment requirements as well as to more cost effectively complete the tank waste treatment mission. Fluidized Bed Steam Reforming (FBSR) is one of the supplementary treatments being considered. FBSR offers a moderate temperature (700-750 C) continuous method by which LAW and other secondary wastes can be processed irrespective of whether they contain organics, nitrates/nitrites, sulfates/sulfides, chlorides, fluorides, and/or radio-nuclides like I-129 and Tc-99. Radioactive testing of Savannah River LAW (Tank 50) shimmed to resemble Hanford LAW and actual Hanford LAW (SX-105 and AN-103) have produced a ceramic (mineral) waste form which is the same as the non-radioactive waste simulants tested at the engineering scale. The radioactive testing demonstrated that the FBSR process can retain the volatile radioactive components that cannot be contained at vitrification temperatures. The radioactive and nonradioactive mineral waste forms that were produced by co-processing waste with kaolin clay in an FBSR process are shown to be as durable as LAW glass.

  10. Radioactive Demonstrations Of Fluidized Bed Steam Reforming With Acutal Hanford Low Activity Wastes Verifying Fbsr As A Supplementary Treatment

    International Nuclear Information System (INIS)

    The U.S. Department of Energy's Office of River Protection is responsible for the retrieval, treatment, immobilization, and disposal of Hanford's tank waste. Currently there are approximately 56 million gallons of highly radioactive mixed wastes awaiting treatment. A key aspect of the River Protection Project cleanup mission is to construct and operate the Waste Treatment and Immobilization Plant (WTP). The WTP will separate the tank waste into high-level waste (HLW) and low-activity waste (LAW) fractions, both of which will subsequently be vitrified. The projected throughput capacity of the WTP LAW Vitrification Facility is insufficient to complete the cleanup mission in the time frame required by the Hanford Federal Facility Agreement and Consent Order, also known as the Tri-Party Agreement (TPA). Therefore, Supplemental Treatment is required both to meet the TPA treatment requirements as well as to more cost effectively complete the tank waste treatment mission. Fluidized Bed Steam Reforming (FBSR) is one of the supplementary treatments being considered. FBSR offers a moderate temperature (700-750 C) continuous method by which LAW and other secondary wastes can be processed irrespective of whether they contain organics, nitrates/nitrites, sulfates/sulfides, chlorides, fluorides, and/or radio-nuclides like I-129 and Tc-99. Radioactive testing of Savannah River LAW (Tank 50) shimmed to resemble Hanford LAW and actual Hanford LAW (SX-105 and AN-103) have produced a ceramic (mineral) waste form which is the same as the non-radioactive waste simulants tested at the engineering scale. The radioactive testing demonstrated that the FBSR process can retain the volatile radioactive components that cannot be contained at vitrification temperatures. The radioactive and nonradioactive mineral waste forms that were produced by co-processing waste with kaolin clay in an FBSR process are shown to be as durable as LAW glass.

  11. FLUIDIZED BED STEAM REFORMING MINERALIZATION FOR HIGH ORGANIC AND NITRATE WASTE STREAMS FOR THE GLOBAL NUCLEAR ENERGY PARTNERSHIP

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C; Michael Williams, M

    2008-01-11

    Waste streams that may be generated by the Global Nuclear Energy Partnership (GNEP) Advanced Energy Initiative may contain significant quantities of organics (0-53 wt%) and/or nitrates (0-56 wt%). Decomposition of high nitrate streams requires reducing conditions, e.g. organic additives such as sugar or coal, to reduce the NO{sub x} in the off-gas to N{sub 2} to meet the Clean Air Act (CAA) standards during processing. Thus, organics will be present during waste form stabilization regardless of which GNEP processes are chosen, e.g. organics in the feed or organics for nitrate destruction. High organic containing wastes cannot be stabilized with the existing HLW Best Developed Available Technology (BDAT) which is HLW vitrification (HLVIT) unless the organics are removed by preprocessing. Alternative waste stabilization processes such as Fluidized Bed Steam Reforming (FBSR) operate at moderate temperatures (650-750 C) compared to vitrification (1150-1300 C). FBSR converts organics to CAA compliant gases, creates no secondary liquid waste streams, and creates a stable mineral waste form that is as durable as glass. For application to the high Cs-137 and Sr-90 containing GNEP waste streams a single phase mineralized Cs-mica phase was made by co-reacting illite clay and GNEP simulated waste. The Cs-mica accommodates up to 30% wt% Cs{sub 2}O and all the GNEP waste species, Ba, Sr, Rb including the Cs-137 transmutation to Ba-137. For reference, the cesium mineral pollucite (CsAlSi{sub 2}O{sub 6}), currently being studied for GNEP applications, can only be fabricated at {ge} 1000 C. Pollucite mineralization creates secondary aqueous waste streams and NO{sub x}. Pollucite is not tolerant of high concentrations of Ba, Sr or Rb and forces the divalent species into different mineral host phases. The pollucite can accommodate up to 33% wt% Cs{sub 2}O.

  12. Steam reforming of methanol over a Cu/ZnO/Al 2O 3 catalyst: a kinetic analysis and strategies for suppression of CO formation

    Science.gov (United States)

    Agrell, Johan; Birgersson, Henrik; Boutonnet, Magali

    Steam reforming of methanol (CH 3OH+H 2O→CO 2+3H 2) was studied over a commercial Cu/ZnO/Al 2O 3 catalyst for production of hydrogen onboard proton exchange membrane (PEM) fuel cell vehicles. A simple power-law rate expression was fitted to experimental data in order to predict the rates of CO 2 and H 2 formation under various reaction conditions. The apparent activation energy ( Ea) was estimated to be 100.9 kJ mol -1, in good agreement with values reported in the literature. Appreciable amounts of CO by-product were formed in the reforming process at low contact times and high methanol conversions. Being a catalyst poison that deactivates the electrocatalyst at the fuel cell anode at concentrations exceeding a few ppm, special attention was paid to the pathways for CO formation and strategies for its suppression. It was found that increasing the steam-methanol ratio effectively decreases CO formation. Likewise, addition of oxygen or air to the steam-methanol mixture minimises the production of CO. By shortening the contact time and lowering the maximum temperature in the reactor, CO production can be further decreased by suppressing the reverse water-gas shift reaction.

  13. Kinetic Study on the Effect of Chromium Addition to Ni-Based Catalysts for the Steam-CO2 Reforming of Methane.

    Science.gov (United States)

    Park, Yoon-Hwa; Li, Peng; Moon, Dong-Ju; Park, Nam-Cook; Kim, Young-Chul

    2016-02-01

    In the present work, the kinetic effects of Ni-based catalysts containing various amounts of Cr on the steam-CO2 reforming (SCR) of methane were studied. Kinetic expressions for the SCR of methane over the Ni-based catalysts have been proposed using the power-law rate expression, based on the kinetic data obtained. In addition, the Arrhenius equation was used for calculating the activation energy. Analysis of the data revealed four simple results. Firstly, the partial pressure of CH4 exerts a major influence on the CH4 conversion rates. Secondly, the CH4 conversion rate is inversely proportional to the partial pressure of CO2. Thirdly, the partial pressure of steam has a very slight effect on the reaction rates. Finally, all the catalysts studied have similar apparent activation energies. PMID:27433614

  14. Synthesis and Activity Test of Cu/ZnO/Al2O3 for the Methanol Steam Reforming as a Fuel Cell’s Hydrogen Supplier

    Directory of Open Access Journals (Sweden)

    IGBN Makertihartha

    2009-05-01

    Full Text Available The synthesis of hydrogen from hydrocarbons through the steam reforming of methanol on Cu/ZnO/Al2O3 catalyst has been investigated. This process is assigned to be one of the promising alternatives for fuel cell hydrogen process source. Hydrogen synthesis from methanol can be carried out by means of methanol steam reforming which is a gas phase catalytic reaction between methanol and water. In this research, the Cu/ZnO/Al2O3 catalyst prepared by the dry impregnation was used. The specific surface area of catalyst was 194.69 m2/gram.The methanol steam reforming (SRM reaction was carried out by means of the injection of gas mixture containing methanol and water with 1:1.2 mol ratio and 20-90 mL/minute feed flow rate to a fixed bed reactor loaded by 1 g of catalyst. The reaction temperature was 200-300 °C, and the reactor pressure was 1 atm. Preceding the reaction, catalyst was reduced in the H2/N2 mixture at 160 °C. This study shows that at 300 °C reaction temperature, methanol conversion reached 100% at 28 mL/minute gas flow rate. This conversion decreased significantly with the increase of gas flow rate. Meanwhile, the catalyst prepared for SRM was stable in 36 hours of operation at 260 °C. The catalyst exhibited a good stability although the reaction condition was shifted to a higher gas flow rate.

  15. Promoting effect of Ru on Ni/Mg(Al)O catalysts in DSS-like operation of CH4 steam reforming

    OpenAIRE

    Miyata, Takeshi; Shiraga, Masato; Li, Dalin; Atake, Ikuo; Shishido, Tetsuya; Oumi, Yasunori; Sano, Tsuneji; Takehira, Katsuomi

    2007-01-01

    Effects of Ru addition on the activity and the sustainability of Ni/Mg(Al)O catalysts were investigated in the daily start-up and shut-down (DSS) operation of the steam reforming of CH4. Mg2.5(Ni0.5)-Al hydrotalcite was prepared by coprecipitation and calcined to form Mg2.5(Al,Ni0.5)O periclase. When the powders of the periclase were dipped in an aqueous solution of Ru(III) nitrate, the hydrotaclite was reconstituted on the surface of Mg2.5(Al,Ni0.5)O particles, resulting in the formation of ...

  16. Preparation and structural characterization of SnO2 and GeO2 methanol steam reforming thin film model catalysts by (HR)TEM

    OpenAIRE

    Lorenz, Harald; Zhao, Qian; Turner, Stuart; Oleg I. Lebedev; Van Tendeloo, Gustaaf; Klötzer, Bernhard; Rameshan, Christoph; Penner, Simon

    2010-01-01

    Structure, morphology and composition of different tin oxide and germanium oxide thin film catalysts for the methanol steam reforming (MSR) reaction have been studied by a combination of (high-resolution) transmission electron microscopy, selected area electron diffraction, dark-field imaging and electron energy-loss spectroscopy. Deposition of the thin films on NaCl(0 0 1) cleavage faces has been carried out by thermal evaporation of the respective SnO2 and GeO2 powders in varying oxygen pa...

  17. The effectiveness of dolomite and Ni-catalyst mixtures for pure H 2 production by methane steam reforming via CO 2 capture

    OpenAIRE

    Seitkaliyeva, Nurgul; Jand, Nader; Foscolo, Pier Ugo

    2016-01-01

    High hydrogen yields have been obtained continuously from steam reforming of methane coupled with simultaneous CO2 capture[1], at lower temperature (630oC) and pressure (1 atm) than those typical of traditional processes (800-900oC,15-30 atm), using calcined dolomite and a pulverized commercial Ni catalyst, in a single step. On the other hand, a pure CO2 stream is obtained by subsequent regeneration of the sorbent, which could be stored. A bubbling fluidized bed contained in a quartz vesse...

  18. Textile wastewater treatment in a bench-scale anaerobic-biofilm anoxic-aerobic membrane bioreactor combined with nanofiltration.

    Science.gov (United States)

    Grilli, Selene; Piscitelli, Daniela; Mattioli, Davide; Casu, Stefania; Spagni, Alessandro

    2011-01-01

    This study evaluated the treatability of textile wastewaters in a bench-scale experimental system, comprising an anaerobic biofilter, an anoxic reactor and an aerobic membrane bioreactor (MBR). The MBR effluent was thereafter treated by a nanofiltration (NF) membrane. The proposed system was demonstrated to be effective in the treatment of the textile wastewater under the operating conditions applied in the study. The MBR system achieved a good COD (90-95%) removal; due to the presence of the anaerobic biofilter, also effective color removal was obtained (70%). The addition of the NF membrane allowed the further improvement in COD (50-80%), color (70-90%) and salt removal (60-70% as conductivity). In particular the NF treatment allowed the almost complete removal of the residual color and a reduction of the conductivity such as to achieve water quality suitable for reuse. PMID:21992723

  19. Development of a standard bench-scale cell for electrochemical studies on inert anodes. Inert Anode/Cathode Program

    Energy Technology Data Exchange (ETDEWEB)

    Windisch, C.F. Jr.; Boget, D.I.

    1986-07-01

    Objective of this work was to develop a standard bench-scale cell for performing short-term ac and dc polarization studies on inert anode candidate materials in molten cryolite. Two designs for electrochemical cells were developed and successfully evaluated in short-term experiments. Both cells consisted on the inert anode as a small cylindrical specimen partially sheathed in alumina, an Al/Al/sub 2/O/sub 3/ reference electrode, and a cryolite bath saturated in alumina. The difference between the two cells was in the design of the cathode. One cell used a bare solid metal cathode; the other used an aluminum pad similar to the Hall-Heroult configuration.

  20. Immobilized lysozyme for the continuous lysis of lactic bacteria in wine: Bench-scale fluidized-bed reactor study.

    Science.gov (United States)

    Cappannella, Elena; Benucci, Ilaria; Lombardelli, Claudio; Liburdi, Katia; Bavaro, Teodora; Esti, Marco

    2016-11-01

    Lysozyme from hen egg white (HEWL) was covalently immobilized on spherical supports based on microbial chitosan in order to develop a system for the continuous, efficient and food-grade enzymatic lysis of lactic bacteria (Oenococcus oeni) in white and red wine. The objective is to limit the sulfur dioxide dosage required to control malolactic fermentation, via a cell concentration typical during this process. The immobilization procedure was optimized in batch mode, evaluating the enzyme loading, the specific activity, and the kinetic parameters in model wine. Subsequently, a bench-scale fluidized-bed reactor was developed, applying the optimized process conditions. HEWL appeared more effective in the immobilized form than in the free one, when the reactor was applied in real white and red wine. This preliminary study suggests that covalent immobilization renders the enzyme less sensitive to the inhibitory effect of wine flavans. PMID:27211619

  1. A contribution to the modelling of steam reformers for natural gas fuelled fuel cell heating systems; Ein Beitrag zur Modellierung von Dampfreformern fuer erdgasbetriebene Brennstoffzellenheizgeraete

    Energy Technology Data Exchange (ETDEWEB)

    Nietzsche, Joerg

    2010-10-29

    The author attempted to verify the assumptions and simplifications of common mathematical models of small-scale steam reformers. The emphasis was on the derivation of important model parameters on the basis of easily identifiable catalyst, fluid and reactor characteristics. An easily validated 2D model of a reformer tube is then used for a wide sensitivity analysis and a comparative investigation of various reactor types. [German] Die Motivation dieser Arbeit liegt in der Ueberpruefung der bislang in mathematischen Modellen von kleintechnischen Dampfreformern getroffenen Annahmen und Vereinfachungen, mit speziellem Augenmerk auf die Aufklaerung der Herkunft wichtiger Modellparameter anhand von leicht bestimmbaren Katalysator-, Fluid- und Reaktoreigenschaften. Ein leicht zu validierendes, zweidimensionales Modell eines Reformerrohres soll im Anschluss fuer eine breit angelegte Sensitivitaetsanalyse und eine vergleichende Untersuchung verschiedener Reaktortypen dienen.

  2. Restoration of cadmium-contaminated paddy soils by washing with ferric chloride: Cd extraction mechanism and bench-scale verification.

    Science.gov (United States)

    Makino, Tomoyuki; Takano, Hiroyuki; Kamiya, Takashi; Itou, Tadashi; Sekiya, Naoki; Inahara, Makoto; Sakurai, Yasuhiro

    2008-01-01

    The ability of FeCl3 to extract Cd from three paddy soils was compared with that of various irons, manganese, and zinc salts to elucidate the extraction mechanism. Manganese, zinc and iron salts (including FeCl3) extracted 4-41%, 8-44% and 24-66% of total Cd, respectively. This difference reflected the pH of the extraction solution, indicating that the primary mechanism of Cd extraction by FeCl3 is proton release coupled with hydroxide generation, as iron hydroxides are insoluble. Washing with FeCl3 led to the formation of Cd-chloride complexes, enhancing Cd extraction from the soils. FeCl3 effectively extracted Cd from all of the three soils compared to HCl that is a conventional washing chemical, when the concentrations of the two washing chemicals were between 15 and 60mM(c) (at above extraction pH 2.4), while the corresponding extraction pH of FeCl3 was slightly higher than HCl. As HCl is the strong acid of complete dissociation, if excess amount of HCl was added to soil, it is possible to give the dissolution of clay minerals in soils. In contrast, proton release from FeCl3 is controlled by the chemical equilibrium of hydroxide formation. While soil fertility properties were affected by a bench-scale soil washing with 45mM(c) FeCl3, adverse effects were not crucial and could be corrected. The bench-scale test confirmed the effectiveness of FeCl3 for removal of soil Cd. The washing had no negative effect on rice yield and lowered the Cd concentration of rice grain and rice straw in a pot experiment. PMID:17919681

  3. A comparison of large-scale electron beam and bench-scale 60Co irradiations of simulated aqueous waste streams

    International Nuclear Information System (INIS)

    The effectiveness of using high energy electron beam irradiation for the removal of toxic organic chemicals from water and wastewater has been demonstrated by commercial-scale experiments conducted at the Electron Beam Research Facility (EBRF) located in Miami, Florida and elsewhere. The EBRF treats various waste and water streams up to 450 l min-1 (120 gal min-1) with doses up to 8 kilogray (kGy). Many experiments have been conducted by injecting toxic organic compounds into various plant feed streams and measuring the concentrations of compound(s) before and after exposure to the electron beam at various doses. Extensive experimentation has also been performed by dissolving selected chemicals in 22,700 l (6000 gal) tank trucks of potable water to simulate contaminated groundwater, and pumping the resulting solutions through the electron beam. These large-scale experiments, although necessary to demonstrate the commercial viability of the process, require a great deal of time and effort. This paper compares the results of large-scale electron beam irradiations to those obtained from bench-scale irradiations using gamma rays generated by a 60Co source. Dose constants from exponential contaminant removal models are found to depend on the source of radiation and initial contaminant concentration. Possible reasons for observed differences such as a dose rate effect are discussed. Models for estimating electron beam dose constants from bench-scale gamma experiments are presented. Data used to compare the removal of organic compounds using gamma irradiation and electron beam irradiation are taken from the literature and a series of experiments designed to examine the effects of pH, the presence of turbidity, and initial concentration on the removal of various organic compounds (benzene, toluene, phenol, PCE, TCE and chloroform) from simulated groundwater

  4. A comparison of large-scale electron beam and bench-scale 60Co irradiations of simulated aqueous waste streams

    Science.gov (United States)

    Kurucz, Charles N.; Waite, Thomas D.; Otaño, Suzana E.; Cooper, William J.; Nickelsen, Michael G.

    2002-11-01

    The effectiveness of using high energy electron beam irradiation for the removal of toxic organic chemicals from water and wastewater has been demonstrated by commercial-scale experiments conducted at the Electron Beam Research Facility (EBRF) located in Miami, Florida and elsewhere. The EBRF treats various waste and water streams up to 450 l min -1 (120 gal min -1) with doses up to 8 kilogray (kGy). Many experiments have been conducted by injecting toxic organic compounds into various plant feed streams and measuring the concentrations of compound(s) before and after exposure to the electron beam at various doses. Extensive experimentation has also been performed by dissolving selected chemicals in 22,700 l (6000 gal) tank trucks of potable water to simulate contaminated groundwater, and pumping the resulting solutions through the electron beam. These large-scale experiments, although necessary to demonstrate the commercial viability of the process, require a great deal of time and effort. This paper compares the results of large-scale electron beam irradiations to those obtained from bench-scale irradiations using gamma rays generated by a 60Co source. Dose constants from exponential contaminant removal models are found to depend on the source of radiation and initial contaminant concentration. Possible reasons for observed differences such as a dose rate effect are discussed. Models for estimating electron beam dose constants from bench-scale gamma experiments are presented. Data used to compare the removal of organic compounds using gamma irradiation and electron beam irradiation are taken from the literature and a series of experiments designed to examine the effects of pH, the presence of turbidity, and initial concentration on the removal of various organic compounds (benzene, toluene, phenol, PCE, TCE and chloroform) from simulated groundwater.

  5. A Phenomenological Study on the Synergistic Role of Precious Metals and the Support in the Steam Reforming of Logistic Fuels on Monometal Supported Catalysts

    Directory of Open Access Journals (Sweden)

    Abdul-Majeed Azad

    2010-01-01

    Full Text Available Clean power source utilizing vast logistic fuel reserves (jet fuels, diesel, and coal would be the main driver in the 21st century for high efficiency. Fuel processors are required to convert these fuels into hydrogen-rich reformate for extended periods in the presence of sulfur, and deliver hydrogen with little or no sulfur to the fuel cell stack. However, the jet and other logistic fuels are invariably sulfur-laden. Sulfur poisons and deactivates the reforming catalyst and therefore, to facilitate continuous uninterrupted operation of logistic fuel processors, robust sulfur-tolerant catalysts ought to be developed. New noble metal-supported ceria-based sulfur-tolerant nanocatalysts were developed and thoroughly characterized. In this paper, the performance of single metal-supported catalysts in the steam-reforming of kerosene, with 260 ppm sulfur is highlighted. It was found that ruthenium-based formulation provided an excellent balance between hydrogen production and stability towards sulfur, while palladium-based catalyst exhibited rapid and steady deactivation due to the highest propensity to sulfur poisoning. The rhodium supported system was found to be most attractive in terms of high hydrogen yield and long-term stability. A mechanistic correlation between the role of the nature of the precious metal and the support for generating clean desulfurized H2-rich reformate is discussed.

  6. Bench-Scale Silicone Process for Low-Cost CO{sub 2} Capture

    Energy Technology Data Exchange (ETDEWEB)

    Vipperla, Ravikumar; Yee, Michael; Steele, Ray; Singh, Surinder; Spiry, Irina; Wood, Benjamin

    2013-12-30

    This report presents system and economic analysis for a carbon capture unit which uses an amino-silicone solvent for CO{sub 2} capture and sequestration (CCS) in a pulverized coal (PC) boiler. The amino-silicone solvent is based on GAP-1 with tri-ethylene glycol (TEG) as a co-solvent. For comparison purposes, the report also shows results for a CCS unit based on a conventional approach using mono-ethanol amine (MEA). At a steam temperature of 395 °C (743 °F), the CCS energy penalty for amino-silicone solvent is only 30.4% which compares to a 35.9% energy penalty for MEA. The increase in COE for the amino-silicone solvent relative to the non-capture case is between 98% and 103% (depending on the solvent cost) which compares to an ~109% COE cost increase for MEA. In summary, the amino-silicone solvent has significant advantages over conventional systems using MEA.

  7. MINERALIZATION OF RADIOACTIVE WASTES BY FLUIDIZED BED STEAM REFORMING (FBSR): COMPARISONS TO VITREOUS WASTE FORMS, AND PERTINENT DURABILITY TESTING

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C

    2008-12-26

    The Savannah River National Laboratory (SRNL) was requested to generate a document for the Washington State Department of Ecology and the U.S. Environmental Protection Agency that would cover the following topics: (1) A description of the mineral structures produced by Fluidized Bed Steam Reforming (FBSR) of Hanford type Low Activity Waste (LAW including LAWR which is LAW melter recycle waste) waste, especially the cage structured minerals and how they are formed. (2) How the cage structured minerals contain some contaminants, while others become part of the mineral structure (Note that all contaminants become part of the mineral structure and this will be described in the subsequent sections of this report). (3) Possible contaminant release mechanisms from the mineral structures. (4) Appropriate analyses to evaluate these release mechanisms. (5) Why the appropriate analyses are comparable to the existing Hanford glass dataset. In order to discuss the mineral structures and how they bond contaminants a brief description of the structures of both mineral (ceramic) and vitreous waste forms will be given to show their similarities. By demonstrating the similarities of mineral and vitreous waste forms on atomic level, the contaminant release mechanisms of the crystalline (mineral) and amorphous (glass) waste forms can be compared. This will then logically lead to the discussion of why many of the analyses used to evaluate vitreous waste forms and glass-ceramics (also known as glass composite materials) are appropriate for determining the release mechanisms of LAW/LAWR mineral waste forms and how the durability data on LAW/LAWR mineral waste forms relate to the durability data for LAW/LAWR glasses. The text will discuss the LAW mineral waste form made by FBSR. The nanoscale mechanism by which the minerals form will be also be described in the text. The appropriate analyses to evaluate contaminant release mechanisms will be discussed, as will the FBSR test results to

  8. DURABILITY TESTING OF FLUIDIZED BED STEAM REFORMER WASTE FORMS FOR SODIUM BEARING WASTE AT IDAHO NATIONAL LABORATORY

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, C; Carol Jantzen, C

    2007-08-27

    Fluidized Bed Steam Reforming (FBSR) processing of Sodium Bearing Waste simulants was performed in December 2006 by THOR{sup sm} Treatment Technologies LLC (TTT) The testing was performed at the Hazen Research Inc. (HRI) pilot plant facilities in Golden, CO. FBSR products from these pilot tests on simulated waste representative of the SBW at the Idaho Nuclear Technology and Engineering Center (INTEC) were subsequently transferred to the Savannah River National Laboratory (SRNL) for characterization and leach testing. Four as-received Denitration and Mineralization Reformer (DMR) granular/powder samples and four High Temperature Filter (HTF) powder samples were received by SRNL. FBSR DMR samples had been taken from the ''active'' bed, while the HTF samples were the fines collected as carryover from the DMR. The process operated at high fluidizing velocities during the mineralization test such that nearly all of the product collected was from the HTF. Active bed samples were collected from the DMR to monitor bed particle size distribution. Characterization of these crystalline powder samples shows that they are primarily Al, Na and Si, with > 1 wt% Ca, Fe and K. The DMR samples contained less than 1 wt% carbon and the HTF samples ranged from 13 to 26 wt% carbon. X-ray diffraction analyses show that the DMR samples contained significant quantities of the Al{sub 2}O{sub 3} startup bed. The DMR samples became progressively lower in starting bed alumina with major Na/Al/Si crystalline phases (nepheline and sodium aluminosilicate) present as cumulative bed turnover occurred but 100% bed turnover was not achieved. The HTF samples also contained these major crystalline phases. Durability testing of the DMR and HTF samples using the ASTM C1285 Product Consistency Test (PCT) 7-day leach test at 90 C was performed along with several reference glass samples. Comparison of the normalized leach rates for the various DMR and HTF components was made with the

  9. Design principles of an integrated natural gas steam reformer for stationary PEMFC systems; Auslegungsprinzipien eines integrierten Erdgas-Dampfreformers fuer stationaere PEM-Brennstoffzellen-Systeme

    Energy Technology Data Exchange (ETDEWEB)

    Grosser, K.

    2006-09-05

    The function, efficiency and economic efficiency of fuel cell systems are defined by various influencing factors, especially in the case of hydrogen production by steam reforming of natural gas. The dissertation describes the design of integrated natural gas steam reformers for PEM fuel cell systems in the electric power range of 1- 10 kW; the influencing factors of the process are investigated and weighted. Design principles are derived from which optimum operating parameters can be defined and which can be used for designing a multitude of components. [German] Die Funktionsfaehigkeit, der Wirkungsgrad und die Wirtschaftlichkeit von Brennstoffzellen-Systemen werden insbesondere bei der Wasserstofferzeugung durch Erdgas-Dampfreformierung durch verschiedene Einflussfaktoren bestimmt. In dieser Dissertation werden die Methodik der Auslegung integrierter Erdgas-Dampfreformer fuer PEM-Brennstoffzellen-Systeme im elektrischen Leistungsbereich von 1-10 kW beschrieben und die prozessbestimmenden Einflussfaktoren untersucht und gewichtet. Daraus werden Auslegungsprinzipien abgeleitet, mit denen sich die optimalen Betriebsparameter ermitteln lassen und die zur konstruktiven Gestaltung einer Vielzahl von Anlagenteilen genutzt werden koennen.

  10. A study on methanol steam reforming to CO2 and H2 over the La2CuO4 nanofiber catalyst

    International Nuclear Information System (INIS)

    The La2CuO4 crystal nanofibers were prepared by using single-walled carbon nanotubes as templates under mild hydrothermal conditions. The steam reforming of methanol (SRM) to CO2 and H2 over such nanofiber catalysts was studied. At the low temperature of 150 deg. C and steam/methanol=1.3, methanol was completely (100%, 13.8 g/h g catalyst) converted to hydrogen and CO2 without the generation of CO. Within the 60 h catalyst lifespan test, methanol conversion was maintained at 98.6% (13.6 g/h g catalyst) and with 100% CO2 selectivity. In the meantime, for distinguishing the advantage of nanoscale catalyst, the La2CuO4 bulk powder was prepared and tested for the SRM reaction for comparison. Compared with the La2CuO4 nanofiber, the bulk powder La2CuO4 showed worse catalytic activity for the SRM reaction. The 100% conversion of methanol was achieved at the temperature of 400 deg. C, with the products being H2 and CO2 together with CO. The catalytic activity in terms of methanol conversion dropped to 88.7% (12.2 g/h g catalyst) in 60 h. The reduction temperature for nanofiber La2CuO4 was much lower than that for the La2CuO4 bulk powder. The nanofibers were of higher specific surface area (105.0 m2/g), metal copper area and copper dispersion. The in situ FTIR and EPR experiments were employed to study the catalysts and catalytic process. In the nanofiber catalyst, there were oxygen vacancies. H2-reduction resulted in the generation of trapped electrons [e] on the vacancy sites. Over the nanofiber catalyst, the intermediate H2CO/HCO was stable and was reformed to CO2 and H2 by steam rather than being decomposed directly to CO and H2. Over the bulk counterpart, apart from the direct decomposition of H2CO/HCO to CO and H2, the intermediate H2COO might go through two decomposition ways: H2COO=CO+H2O and H2COO=CO2+H2. - Graphical abstract: The steam reforming of methanol (SRM) to CO2 and H2 over La2CuO4 nanofiber catalyst was studied. At the temperature as low as 150 deg. C

  11. Crucible melts and bench-scale ISV [in situ vitrification] tests on simulated wastes in INEL [Idaho National Engineering Laboratory] soils

    International Nuclear Information System (INIS)

    This report summarizes the results of eight crucible melt tests and three bench-scale in situ vitrification (ISV) test that were performed on simulated metals/soils mixtures containing actual site soils from the Idaho National Engineering Laboratory (INEL). The crucible melt and bench-scale ISV tests are a part of efforts by the Pacific Northwest Laboratory (PNL) to assist the INEL in conducting a treatability study on ISV for application to the mixed waste buried at the INEL subsurface disposal area (SDA). The crucible melt tests were performed to evaluate the effect of various chemical additives and metal oxidation techniques on soil melting temperatures, melt viscosities, metals versus electrode oxidation potentials, and metals incorporation in the glass. The bench-scale ISV tests were performed to supplement the existing ISV data base with information on certain hazardous materials that have not been adequately evaluated in previous ISV tests. These materials included five EP toxicity metals, various volatile organic materials fixed in a cementitious matrix [including carbon tetrachloride (CCl4), trichloroethylene (TCE), and tetrachloroethylene (PCE)], and asbestos. In addition, the bench-scale test were used to evaluated the effect of the proposed chemical additive on ISV processing performance and product quality. 8 refs., 24 figs., 19 tabs

  12. Performance evaluation and comparison of fuel processors integrated with PEM fuel cell based on steam or autothermal reforming and on CO preferential oxidation or selective methanation

    International Nuclear Information System (INIS)

    Highlights: • Modeling of different fuel processors integrated with PEM fuel cell stack. • Steam or autothermal reforming + CO selective methanation or preferential oxidation. • Reforming of different hydrocarbons: gasoline, light diesel oil, natural gas. • 5 kWe net systems comparison via energy efficiency and primary fuel rate consumed. • Highest net efficiency: steam reformer + CO selective methanation based system. - Abstract: The performances of four different auxiliary power unit (APU) schemes, based on a 5 kWe net proton exchange membrane fuel cell (PEM-FC) stack, are evaluated and compared. The fuel processor section of each APU is characterized by a reformer (autothermal ATR or steam SR), a non-isothermal water gas shift (NI-WGS) reactor and a final syngas catalytic clean-up step: the CO preferential oxidation (PROX) reactor or the CO selective methanation (SMET) one. Furthermore, three hydrocarbon fuels, the most commonly found in service stations (gasoline, light diesel oil and natural gas) are considered as primary fuels. The comparison is carried out examining the results obtained by a series of steady-state system simulations in Aspen Plus® of the four different APU schemes by varying the fed fuel. From the calculated data, the performance of CO-PROX is not very different compared to that of the CO-SMET, but the performance of the SR based APUs is higher than the scheme of the ATR based APUs. The most promising APU scheme with respect to an overall performance target is the scheme fed with natural gas and characterized by a fuel processor chain consisting of SR, NI-WGS and CO-SMET reactors. This processing reactors scheme together with the fuel cell section, notwithstanding having practically the same energy efficiency of the scheme with SR, NI-WGS and CO-PROX reactors, ensures a less complex scheme, higher hydrogen concentration in the syngas, lower air mass rate consumption, the absence of nitrogen in the syngas and higher potential power

  13. Experimental investigations on temperature distributions of flame sections in a bench-scale opposed multi-burner gasifier

    International Nuclear Information System (INIS)

    Based on a flame image processing technique, the temperature distributions of flame sections in a bench-scale opposed multi-burner (OMB) gasifier is visualized. With the assumption of the gray radiation, a charge-coupled device camera installed on the top of the gasifier is used to capture the approximately monochromatic radiant images under the visible wavelengths. To reduce the errors, the camera is calibrated by a blackbody cavity. By using the two-color method, the radiant intensity captured by the camera is calculated from the pair of red/green with reference to the calibration data. Based on the assumption of rotational symmetry, the temperature distributions of flame sections are reconstructed by the Filtered back-projection method. The results show that the temperature distributions of flame sections are consistent with the flame structure. The flame temperature distribution at the burner plane ranges from 1700 to 2100 deg. C. The section is farther from the burner plane, the temperature is lower. The relative errors between the calculated temperatures and the measured temperatures by a B-type thermocouple are no greater than ±6.4%. The research results establish the foundation for understanding the flame internal structure and temperature distribution in the OMB gasifier

  14. Dynamics of bacterial populations during bench-scale bioremediation of oily seawater and desert soil bioaugmented with coastal microbial mats.

    Science.gov (United States)

    Ali, Nidaa; Dashti, Narjes; Salamah, Samar; Sorkhoh, Naser; Al-Awadhi, Husain; Radwan, Samir

    2016-03-01

    This study describes a bench-scale attempt to bioremediate Kuwaiti, oily water and soil samples through bioaugmentation with coastal microbial mats rich in hydrocarbonoclastic bacterioflora. Seawater and desert soil samples were artificially polluted with 1% weathered oil, and bioaugmented with microbial mat suspensions. Oil removal and microbial community dynamics were monitored. In batch cultures, oil removal was more effective in soil than in seawater. Hydrocarbonoclastic bacteria associated with mat samples colonized soil more readily than seawater. The predominant oil degrading bacterium in seawater batches was the autochthonous seawater species Marinobacter hydrocarbonoclasticus. The main oil degraders in the inoculated soil samples, on the other hand, were a mixture of the autochthonous mat and desert soil bacteria; Xanthobacter tagetidis, Pseudomonas geniculata, Olivibacter ginsengisoli and others. More bacterial diversity prevailed in seawater during continuous than batch bioremediation. Out of seven hydrocarbonoclastic bacterial species isolated from those cultures, only one, Mycobacterium chlorophenolicum, was of mat origin. This result too confirms that most of the autochthonous mat bacteria failed to colonize seawater. Also culture-independent analysis of seawater from continuous cultures revealed high-bacterial diversity. Many of the bacteria belonged to the Alphaproteobacteria, Flavobacteria and Gammaproteobacteria, and were hydrocarbonoclastic. Optimal biostimulation practices for continuous culture bioremediation of seawater via mat bioaugmentation were adding the highest possible oil concentration as one lot in the beginning of bioremediation, addition of vitamins, and slowing down the seawater flow rate. PMID:26751253

  15. Bench-scale cross flow filtration of Tank S-107 sludge slurries and Tank C-107 supernatant

    International Nuclear Information System (INIS)

    Hanford tank waste filtration experiments were conducted using a bench-scale cross flow filter on 8 wt%, 1.5 wt%, and 0.05 wt% Tank S- 107 sludge slurries and on Tank C-107 supernatant. For comparison, two simulants each with solids loadings of 8 wt% and 0.05 wt% were also tested. The purpose of the tests was to determine the efficacy of cross flow filtration on slurries of various solids loadings. -In addition, filtrate flux dependency on axial velocity and transmembrane pressure was sought so that conditions for future experiments might be better selected. The data gathered are compared to the simulants and three cross flow filtration models. A two- parameter central composite design which tested. transmembrane pressure from 5 to 40 psig and axial Velocity from 3 to 9 ft/s was used for all feeds. The cross flow filter effectively removed solids from the liquid, as 19 of 20 filtrate samples had particle concentrations below the resolution limit of the photon correlation spectrometer used in the Hanford Radiocolloid Laboratory. Radiochemical analysis indicate that all filtrate samples were below Class A waste classification standards for 9OSr and transuranics

  16. Bench-scale column experiments to study the containment of Cr(VI) in confined aquifers by bio-transformation.

    Science.gov (United States)

    Shashidhar, T; Philip, Ligy; Murty Bhallamudi, S

    2006-04-17

    Bench-scale soil column experiments were conducted to study the effectiveness of Cr(VI) containment in confined aquifers using in situ bio-transformation. Batch adsorption studies were carried out to estimate the adsorption capacities of two different soils for Cr(VI) and Cr(III). Bio-kinetic parameters were evaluated for the enriched microbial system. The inhibition constant, evaluated using Monod's inhibition model, was found to be 11.46 mg/L of Cr(VI). Transport studies indicated that it would not be possible to contain Cr(VI) by adsorption alone. Transport and bio-transformation studies indicated that the pore velocity and the initial bio-mass concentration significantly affect the containment process. In situ bio-remediation is effective in the case of silty aquifers. Cr(VI) concentration of 25 mg/L was effectively contained within 60 cm of a confined silty aquifer. Cr(VI) containment could be achieved in sandy aquifers when the pore velocity was very low and the initial augmented bio-mass was high. A bio-barrier of approximately one meter width would be able to contain Cr(VI) if the initial Cr(VI) concentration is as much as 25 mg/L. PMID:16263213

  17. Production of uranium hexafluoride by the catalysed fluorox process: pilot plant and supporting bench-scale studies

    International Nuclear Information System (INIS)

    The feasibility of producing UF6 by the catalysed reaction of UF4 with oxygen (the Fluorox process) was investigated in a 150 mm diameter fluidised bed reactor and in supporting bench-scale experiments. The rate of the Fluorox reaction in batch experiments was increased by an order of magnitude with 1 to 5 per cent catalyst (containing 3 to 4 per cent platinum on alumina). The maximum UF6 production rate at 650 deg. C was 0.9 kg h-1. However, the platinum catalyst was completely poisoned after production of only 1 and 20 kg UF6 per kg of catalyst when using respectively French and British UF4. Regeneration of the catalyst was demonstrated to be technically feasible by washing with water or ammonium oxalate solution or treating with hydrogen and hydrogen fluoride at 350-650 deg. C. However, since the very fast rate of poisoning would necessitate higher catalyst concentrations and/or frequent regeneration, the catalysed Fluorox process in unlikely to be economically competitive with the direct fluorination of UF4

  18. Hydrogen Production by Low-temperature Steam Reforming of Bio-oil over Ni/HZSM-5 Catalyst%在Ni/HZSM-5催化剂上低温水蒸汽重整生物油制氢

    Institute of Scientific and Technical Information of China (English)

    仇松柏; 宫璐; 刘璐; 洪成贵; 袁丽霞; 李全新

    2011-01-01

    We investigated high catalytic activity of Ni/HZSM-5 catalysts synthesized by the impregnation method, which was successfully applied for low-temperature steam reforming of bio-oil.The influences of the catalyst composition, reforming temperature and the molar ratio of steam to carbon fed on the stream reforming process of bio-oil over the Ni/HZSM-5 catalysts were investigated in the reforming reactor.The promoting effects of current passing through the catalyst on the bio-oil reforming were also studied using the electrochemical catalytic reforming approach.By comparing Ni/HZSM-5 with commonly used Ni/Al2O3 catalysts, the Ni20/ZSM catalyst with Ni-loading content of about 20% on the HZSM-5 support showed the highest catalytic activity.Even at 450 ℃, the hydrogen yield of about 90% with a near complete conversion of bio-oil was obtained using the Ni20/ZSM catalyst.It was found that the performance of the bio-oil reforming was remarkably enhanced by the HZSM-5 supporter and the current through the catalyst.The features of the Ni/HZSM-5 catalysts were also investigated via X-ray diffraction, inductively coupled plasma and atomic emission spectroscopy, hydrogen temperature-programmed reduction, and Brunauer-Emmett-Teller methods.

  19. Homogeneous precipitation synthesis of CuO–ZrO2–CeO2–Al2O3 nanocatalyst used in hydrogen production via methanol steam reforming for fuel cell applications

    International Nuclear Information System (INIS)

    Graphical abstract: In this study, the effect of ceria and/or zirconia on the performance of CuO–Al2O3 nanocatalysts in the steam reforming of methanol was investigated. CuO–ZrO2–Al2O3, CuO–CeO2–Al2O3 and CuO–ZrO2–CeO2–Al2O3 nanocatalysts were synthesized via homogeneous precipitation method. It was found out that ceria addition leads to better dispersion of Cu, smaller particle size and more uniform distribution which leads to better methanol conversion, low CO production and high stability. The methanol conversion over CuO–CeO2–Al2O3 reaches to 100% at 240 °C while no CO was detected in this temperature. - Highlights: • Homogeneous precipitation synthesis of CuO–ZrO2–CeO2–Al2O3 nanocatalyst. • Enhanced effect of ceria–zirconia on properties and performance of the nanocatalyst. • Conversion of 100% at 240 °C with no CO production over nanocatalyst. • High time on stream of CuO–ZrO2–CeO2–Al2O3 nanocatalyst in methanol steam reforming. • Suggested a reaction pathway methanol steam reforming over nanocatalyst. - Abstract: The CuO–ZrO2–CeO2–Al2O3 catalysts for production of hydrogen via methanol steam reforming were prepared by the homogeneous precipitation method using urea hydrolysis, and the effect of presence of ceria and zirconia on methanol conversion was investigated. Prepared catalysts were characterized by XRD, FESEM, EDX, BET and FTIR analysis. XRD analysis showed that the addition of ceria to nanocatalysts made copper crystallites smaller. The FESEM results indicated that ceria enhanced the surface homogeneity of the samples and made particle size smaller. Catalytic performance tests proved the good practicability and high stability of synthesized catalysts via the homogeneous precipitation method for steam reforming of methanol. Furthermore, the ceria containing catalyst was the best among samples. The CuO–CeO2–Al2O3 catalyst had better methanol conversion with low CO production. The stability test

  20. Characterization of catalysts Rh and Ni/CexZr1-xO2 for hydrogen production by ethanol steam reforming

    International Nuclear Information System (INIS)

    This work concerned a study on catalytic behaviour of metallic catalysts (Rh or Ni) supported on earth rare oxides CexZr1-xO2 in ethanol steam reforming in order to produce hydrogen. Catalyst 1%Rh/Ce0,50Zr0,50O2 showed a good activity with a good hydrogen yield. We turned a study onto understanding inter-conversion reaction between H2, CO and CO2 which lead to CH4 formation. We also studied intrinsic properties of catalysts. We confirmed basic character of catalysts and a good hydrogenation activity. A good activity in CO hydrogenation allowed to evidence a necessity to use a catalyst which is less active in hydrogenation reaction and with a basic character in order to improve hydrogen yield. (author)

  1. CO-free hydrogen from steam-reforming of bioethanol over ZnO-supported cobalt catalysts. Effect of the metallic precursor

    Energy Technology Data Exchange (ETDEWEB)

    Llorca, Jordi; De la Piscina, Pilar Ramirez; Sales, Joaquim; Homs, Narcis [Departament de Quimica Inorganica, Universitat de Barcelona, c/Marti i Franques 1-11, 08028 Barcelona (Spain); Dalmon, Jean-Alain [Institut de Recherches sur la Catalyse-CNRS, 2 Avenue Albert Einstein, 69626 Villeurbanne (France)

    2003-07-25

    The ethanol steam-reforming reaction was studied over ZnO-supported cobalt catalysts (10wt.% Co). Catalysts were prepared by impregnation of nitrate and carbonyl cobalt precursors. Characterization was accomplished by transmission electron microscopy (TEM), Raman spectroscopy, UV-Vis diffuse reflectance spectroscopy (DRS), X-ray diffraction (XRD), and in situ techniques: magnetic measurements, and diffuse reflectance infrared spectroscopy (DRIFT) coupled to mass spectrometry. The use of Co{sub 2}(CO){sub 8} as precursor produced a catalyst that was highly stable and selective for the production of CO-free hydrogen at reaction temperature as low as 623K. The only by-product was methane and selectivity of 73% to H{sub 2} and 25% to CO{sub 2} was obtained. Under reaction conditions, the catalyst showed 92% of reduced cobalt, mainly as small particles.

  2. The cycle use test of Pt based catalyst for the steam reforming of naphthalene / benzene as model tar compounds of biomass gasification

    Energy Technology Data Exchange (ETDEWEB)

    Furusawa, Takeshi; Saito, Katsuhiko; Sato, Masahide; Suzuki, Noboru [Utsunomiya Univ. (Japan). Graduate School of Engineering

    2010-07-01

    Although Pt/Al{sub 2}O{sub 3} catalyst showed high and stable activity (carbon conv. to gas: 90%) for steam reforming of naphthalene/benzene at 1073 K with S/C=3, this catalyst gradually lost its activity at 1023 K with S/C=3 due to deposition of carboneous species. Two kinds of regeneration treatment was conducted to enlongate the life time of Pt/Al{sub 2}O{sub 3} catalyst. Although regeneration treatment completely remove the carboneous species from catalyst, mild oxidation treatment led to decrease activity due to sintering of Pt particles. On the contrary, hydrogen treatment led to maintain activity until 5th cycle test. It was concluded from these obtained results that hydrogen treatment is suitable regeneration method during cycle test in the case of Pt/Al{sub 2}O{sub 3} catalyst. (orig.)

  3. Stabilization of Hydrogen Production via Methanol Steam Reforming in Microreactor by Al2O3 Nano-Film Enhanced Catalyst Adhesion.

    Science.gov (United States)

    Jeong, Heondo; Na, Jeong-Geol; Jang, Min Su; Ko, Chang Hyun

    2016-05-01

    In hydrogen production by methanol steam reforming reaction with microchannel reactor, Al2O3 thin film formed by atomic layer deposition (ALD) was introduced on the surface of microchannel reactor prior to the coating of catalyst particles. Methanol conversion rate and hydrogen production rate, increased in the presence of Al2O3 thin film. Over-view and cross-sectional scanning electron microscopy study showed that the adhesion between catalyst particles and the surface of microchannel reactor enhanced due to the presence of Al2O3 thin film. The improvement of hydrogen production rate inside the channels of microreactor mainly came from the stable fixation of catalyst particles on the surface of microchannels. PMID:27483762

  4. Investigation of promoted Cu/ZnO/Al{sub 2}O{sub 3} methanol steam reforming nanocatalysts by full factorial design

    Energy Technology Data Exchange (ETDEWEB)

    Sharifi Pajaie, H.; Taghizadeh, M. [Babol University of Technology, Chemical Engineering Department, Babol (Iran, Islamic Republic of)

    2012-10-15

    A Cu/ZnO/Al{sub 2}O{sub 3} nanocatalyst was applied for hydrogen production via steam reforming of methanol in a fixed-bed reactor. Modified forms of the catalyst were prepared by adding small amounts of Ba, Zr, and Ce oxides. The catalysts were characterized by means of N{sub 2} adsorption-desorption, X-ray diffraction, and scanning electron microscope techniques. Full factorial design was used to optimize the required number of experiments and evaluate the catalytic activity in a fixed-bed reactor. The oxide additives reduced the production of carbon monoxide and increased the selectivity of carbon dioxide as well as the yield of hydrogen production. Among the studied catalysts, the Cu/ZnO/Al{sub 2}O{sub 3}/CeO{sub 2}/ZrO{sub 2} catalyst presented the best performance. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Single Pass Flow-Through (SPFT) Test Results of Fluidized Bed Steam Reforming (FBSR) Waste Forms used for LAW Immobilization - 12252

    International Nuclear Information System (INIS)

    Several supplemental technologies for treating and immobilizing Hanford low activity waste (LAW) are being evaluated. One such immobilization technology being considered is the Fluidized Bed Steam Reforming (FBSR) product, which is granular and will be monolithed into a final waste form. The granular component is composed of insoluble sodium aluminosilicate (NAS) feldspathoid minerals. Production of the FBSR mineral product has been demonstrated at the industrial, engineering, and laboratory scales. Single-Pass Flow-Through (SPFT) tests at various flow rates have been conducted with the granular products fabricated using the engineering- and laboratory-scale methods. Results show that the forward dissolution rate for the engineering-scale mineral product is 0.6 (±0.2)x10-3 g/m2d while the forward dissolution rate for the laboratory-scale mineral product is 1.3 (±0.5)x10-3 g/m2d. (authors)

  6. Low CO content hydrogen production from oxidative steam reforming of ethanol over CuO-CeO2 catalysts at low-temperature

    Institute of Scientific and Technical Information of China (English)

    Xue; Han; Yunbo; Yu; Hong; He; Jiaojiao; Zhao

    2013-01-01

    CuO-CeO2 catalysts were prepared by a urea precipitation method for the oxidative steam reforming of ethanol at low-temperature.The catalytic performance was evaluated and the catalysts were characterized by inductively coupled plasma atomic emission spectroscopy,X-ray diffraction,temperature-programmed reduction,field emission scanning electron microscopy and thermo-gravimetric analysis.Over CuOCeO2 catalysts,H2 with low CO content was produced in the whole tested temperature range of 250–450 C.The non-noble metal catalyst 20CuCe showed higher H2production rate than 1%Rh/CeO2 catalyst at 300–400 C and the advantage was more obvious after 20 h testing at400 C.These results further confirmed that CuO-CeO2 catalysts may be suitable candidates for low temperature hydrogen production from ethanol.

  7. Study of a H2 separating membrane reactor for methane steam reforming at conditions relevant for power processes with CO2 capture

    International Nuclear Information System (INIS)

    We present a one dimensional, steady state model for a catalytic membrane reactor used for methane steam reforming. We have solved the model for conditions that could be relevant for integration of the reactor in a power process with CO2 capture. The model behaved as expected when several important system parameters were varied. The results show that the operating conditions for the membrane reactor will have a great impact on the design of the power process. It is therefore crucial to understand the behavior of the membrane reactor if one wants to integrate it in a power process with CO2 capture. The best choice of operating conditions must be found through consideration of the whole power process

  8. Pembuatan Katalis Cu/ZnO/Al2O3 untuk Proses Steam Reforming Metanol menjadi Hidrogen sebagai Bahan Bakar Alternatif

    Directory of Open Access Journals (Sweden)

    Husni Husin

    2010-06-01

    Full Text Available Study on the use of copper zinc oxide supported on alumina catalyst for steam reforming of methanol to hydrogen has been done. The aim of this work is to study the catalytic properties of copper based catalysts used in the steam reforming of methanol. This method is known as one of the most favorable catalytic processes for producing hydrogen on-board. The catalyst was prepared by impregnation method with Cu loading of 5%, 10%, and 15%,. The X-ray diffraction pattern shows that the catalyst compositions are Cu, CuO, ZnO, and Al2O3. The reactions were carried out in the fixed bed tubular reactor operating at temperatures of 150oC, 200oC, 250oC, 300oC, and 350oC and atmospheric pressure. The product was analyzed using Shimadzu Gas Chromatography GC 8A with mole sieve 5A and porapak-N column 80/100 mesh. The performance of the catalyst shows that the highest methanol conversion was 86% over Cu/ZnO/Al2O3 catalyst with 15% of Cu loading. The selectivity and yield of hydrogen was 66% and 57% respectively over Cu/ZnO/Al2O3 catalyst with 15% of Cu loading. Selectivity of carbon dioxide is 18% over Cu/ZnO/Al2O3 catalyst with 15% of Cu loading at 300oC. Keywords: alumina oxide catalyst, copper zinc oxide, hydrogen, impregnation

  9. Bench-scale testing of on-line control of column flotation using a novel analyzer. Second quarterly technical progress report, January 1, 1993--March 31, 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-04-16

    This document contains the second quarterly technical progress report for PTI`s Bench-Scale Testing Project of a circuit integrating PTI`s KEN-FLOTE{trademark} Column Flotation Technology and PTI`s On-Line Quality Monitor and Control System. The twelve-month project involves installation and testing of a 200--300 lb/hr. bench-scale testing circuit at PETC`s Coal Preparation Process Research Facility (CPPRF) for two bituminous coals (Upper Freeport and Pittsburgh No. 8 Seam Raw Coals). The project schedule timeline by task series for the twelve month project, as it was laid out in the initial Project Work Plan. At the present time, all tasks are progressing according to schedule with the exception of the Task 800 Circuit Testing and Sample Prep and Task 1000 Circuit Decommissioning, which have slipped approximately five weeks due to delays incurred within in the project.

  10. Testing of a Ni-Al{sub 2}O{sub 3} catalyst for methane steam reforming using different reaction systems

    Energy Technology Data Exchange (ETDEWEB)

    De Miguel, N.; Manzanedo, J. [IKERLAN S. Coop, Alternative Generation Systems Area, Minano (Alava) (Spain); Arias, P.L. [University of the Basque Country, School of Engineering, Department of Chemical and Environmental Engineering, Bilbao (Spain)

    2012-04-15

    Ni-Al{sub 2}O{sub 3} catalyst activity was tested for methane steam reforming using two different reaction systems: a catalyst particle bed (0.42-0.5 mm catalyst particles diluted in SiC) with a surface area-to-volume ratio SA/V of 910 m{sup -1} and a porosity {epsilon} of 52 % and a catalyst-coated metal monolith with an SA/V of 3300 m{sup -1} and an {epsilon} of 86 %. Under a steam-to-carbon ratio of 2.5 and at a temperature of 700 C, the highest specific reaction rates were found for the catalyst-coated monolith. The high SA/V and {epsilon}, together with the high rate of heat transfer of the metal monolith were found to be responsible of this optimum behavior. However, in both systems, the Ni-Al{sub 2}O{sub 3} catalyst suffered a catalyst deactivation during operation. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  11. Effect of temperature downshifts on a bench-scale hybrid A/O system: Process performance and microbial community dynamics.

    Science.gov (United States)

    Zhou, Hexi; Li, Xiangkun; Chu, Zhaorui; Zhang, Jie

    2016-06-01

    Effect of temperature downshifts on process performance and bacterial community dynamics was investigated in a bench-scale hybrid A/O system treating real domestic wastewater. Results showed that the average COD removal in this system reached 90.5%, 89.1% and 90.3% for Run 1 (25 °C), Run 2 (15 °C) and Run 3 (10 °C), respectively, and variations in temperature barely affected the effluent COD concentration. The average removal efficiencies of NH4(+)-N were 98.4%, 97.8%, 95.7%, and that of TN were 77.1%, 61.8%, 72% at 25 °C, 15 °C and 10 °C, respectively. Although the hybrid system was subjected to low temperature, this process effectively removed NH4(+)-N and TN even at 10 °C with the average effluent concentrations of 2.4 mg/L and 14.3 mg/L, respectively. Results from high-throughput sequencing analysis revealed that when the operation temperature decreased from 25 °C to 10 °C, the richness and diversity indexes of the system decreased in the sludge samples, while underwent an increase in the biofilm samples. Furthermore, the major heterotrophic bacteria consisted of Lewinella, Lutimonas, Chitinophaga and Fluviicola at 10 °C, which could be central to effective COD removal at low temperature. Additionally, Azospira, one denitrifying-related genus increased from 0.4% to 4.45% in the biofilm samples, with a stable TN removal in response to temperature downshifts. Nitrosomonas and Nitrospira increased significantly in the biofilm samples, implying that the attached biofilm contributed to more nitrification at low temperature. PMID:27035388

  12. Archaeal and bacterial community dynamics and bioprocess performance of a bench-scale two-stage anaerobic digester.

    Science.gov (United States)

    Gonzalez-Martinez, Alejandro; Garcia-Ruiz, Maria Jesus; Rodriguez-Sanchez, Alejandro; Osorio, Francisco; Gonzalez-Lopez, Jesus

    2016-07-01

    Two-stage technologies have been developed for anaerobic digestion of waste-activated sludge. In this study, the archaeal and bacterial community structure dynamics and bioprocess performance of a bench-scale two-stage anaerobic digester treating urban sewage sludge have been studied by the means of high-throughput sequencing techniques and physicochemical parameters such as pH, dried sludge, volatile dried sludge, acid concentration, alkalinity, and biogas generation. The coupled analyses of archaeal and bacterial communities and physicochemical parameters showed a direct relationship between archaeal and bacterial populations and bioprocess performance during start-up and working operation of a two-stage anaerobic digester. Moreover, results demonstrated that archaeal and bacterial community structure was affected by changes in the acid/alkalinity ratio in the bioprocess. Thus, a predominance of the acetoclastic methanogen Methanosaeta was observed in the methanogenic bioreactor at high-value acid/alkaline ratio, while a predominance of Methanomassilicoccaeceae archaea and Methanoculleus genus was observed in the methanogenic bioreactor at low-value acid/alkaline ratio. Biodiversity tag-iTag sequencing studies showed that methanogenic archaea can be also detected in the acidogenic bioreactor, although its biological activity was decreased after 4 months of operation as supported by physicochemical analyses. Also, studies of the VFA producers and VFA consumers microbial populations showed as these microbiota were directly affected by the physicochemical parameters generated in the bioreactors. We suggest that the results obtained in our study could be useful for future implementations of two-stage anaerobic digestion processes at both bench- and full-scale. PMID:26940050

  13. Destruction of hazardous and mixed wastes using mediated electrochemical oxidation in a Ag(II)HNO3 bench scale system

    International Nuclear Information System (INIS)

    Mediated Electrochemical Oxidation (MEO) is a promising technology for the destruction of organic containing wastes and the remediation of mixed wastes containing transuranic components. The combination of a powerful oxidant and an acid solution allows the conversion of nearly all organics, whether present in hazardous or in mixed waste, to carbon dioxide. Insoluble transuranics are dissolved in this process and may be recovered by separation and precipitation.The MEO technique offers several advantages which are inherent in the system. First, the oxidation/dissolution processes are accomplished at near ambient pressures and temperatures (30-70 degrees C). Second, all waste stream components and oxidation products (with the exception of evolved gases) are contained in an aqueous environment. This electrolyte acts as an accumulator for inorganics which were present in the original waste stream, and the large volume of electrolyte provides a thermal buffer for the energy released during oxidation of the organics. Third, the generation of secondary waste is minimal, as the process needs no additional reagents. Finally, the entire process can be shut down by simply turning off the power, affording a level of control unavailable in some other techniques.Numerous groups, both in the United States and Europe, have made substantial progress in the last decade towards understanding the mechanistic pathways, kinetics, and engineering aspects of the process. At Lawrence Livermore National Laboratory, substantial contributions have been made to this knowledge base in these areas and others. Conceptual design and engineering development have been completed for a pilot plant-scale MEO system, and numerous data have been gathered on the efficacy of the process for a wide variety of anticipated waste components. This presentation will review the data collected at LLNL for a bench scale system based primarily on the use of a Ag(II) mediator in a nitric acid electrolyte; results

  14. Investigations into NOx emissions and burnout for coals with high ash content in a bench scale test facility

    Energy Technology Data Exchange (ETDEWEB)

    Greul, U.; Kluger, F.; Peter, G.; Spliethoff, H.; Hein, K.R.G. [University of Stuttgart, Stuttgart (Germany). Inst. fuer Verfahrenstechnik und Dampfkesselwesen

    2000-07-01

    At the Stuttgart University's Institute of Process Engineering and Power Plant Technology (IVD) investigations of in-furnace DeNOx technologies with regard to their NOx reduction efficiency are carried out using an electrically heated bench-scale test facility to evaluate the effect of different process parameters independently. The DeNOx technologies of air and fuel staging have been demonstrated to be effective control techniques to reduce NOx from stationary sources. For a wide range of brown and hard coals from Europe, South Africa and Australia test runs with air-staged combustion have been carried out. The ash content of the hard coals used was in the range between 8 and 28%. The investigated parameters were temperature (1000-1300{degree}C), stoichiometry (1.25-0.55), and residence time (1-6 s) in the fuel rich primary zone. With increasing temperatures and residence times in fuel-rich conditions in air-staged combustion NOx emissions below 300 mg/m{sup 3} can be achieved even with hard coals. For a few brown coals NOx values lower than 100 mg/m{sup 3} are possible. Dependent on the coal rank individual parameters are more important than others. For low and medium volatile hard coals the increasing of the residence time is more effective than higher temperature or lower air ratios in the primary zone. However, with high volatile hard coal or brown coal as primary fuel the influence of temperature and stoichiometry in the primary zone plays a key role for NOx reduction effectiveness. The burnout led to restrictions in large scale applications for air-staged combustion especially with hard coals as primary fuel. Investigations at different primary air ratios and temperatures show the effect of these parameters on the burnout values along the course of combustion. 7 refs., 14 figs., 2 tabs.

  15. Electrical resistivity tomography as a tool for monitoring CO2 injection: Demonstration of leakage detection during bench-scale experiments

    Science.gov (United States)

    Breen, S. J.; Carrigan, C. R.; LaBrecque, D. J.; Detwiler, R. L.

    2011-12-01

    Field-scale studies have shown Electrical Resistivity Tomography (ERT) to be an effective tool for imaging resistivity anomalies and monitoring infiltration events in the near subsurface. ERT also shows potential for monitoring CO2 injections, despite deployment challenges in the deep subsurface. We present results from analog bench-scale experiments aimed at evaluating the ability of ERT to quantify the volume and spatial distribution of a gas injected into a brine-saturated porous medium. We injected measured volumes of gas into translucent chambers filled with quartz sand, lined with electrodes, and saturated with a low resistivity salt solution. Between injections, a CCD camera captured high-resolution images, and an ERT data acquisition system scanned the chamber. Using the CCD images, quantitative visualization techniques resulted in high-resolution measurements of the spatial distribution and saturation of the injected gas. Direct comparison to inverted resistivity fields then provided a quantitative measure of the ability of ERT to estimate the total volume of injected gas and its spatial distribution within the chamber. We present results from two experiments designed to represent different injection scenarios: (A) low injection rate and strong capillary barrier, and (B) high injection rate and weaker capillary barrier. Results show that ERT provides good estimates of the shape, size and location of the primary gas plume, but underestimates gas content and does not detect thin pathways of gas from the injection port or within the overlying capillary barrier. However, ERT measurements did detect a change in saturation within the primary plume caused by leakage through the capillary barrier in (B), demonstrating the potential utility of ERT as a leakage-monitoring tool. Repeated ERT scans during our experiments led to degradation in data quality that corresponded with an increase in measured contact resistance. Decreased data quality over time is clearly a

  16. The effect of potassium addition to Pt supported on YSZ on steam reforming of mixtures of methane and ethane

    NARCIS (Netherlands)

    Graf, Patrick O.; Mojet, Barbara L.; Lefferts, Leon

    2009-01-01

    The influence of potassium addition on Pt supported on yttrium-stabilized zirconia (YSZ) was studied with FT-IR CO adsorption and CO-FT-IR-TPD, in order to understand the effect of potassium on the performance of the catalyst in reforming of mixtures of methane and ethane. Potassium modification of

  17. A study on methanol steam reforming to CO 2 and H 2 over the La 2CuO 4 nanofiber catalyst

    Science.gov (United States)

    Gao, Lizhen; Sun, Gebiao; Kawi, Sibudjing

    2008-01-01

    The La 2CuO 4 crystal nanofibers were prepared by using single-walled carbon nanotubes as templates under mild hydrothermal conditions. The steam reforming of methanol (SRM) to CO 2 and H 2 over such nanofiber catalysts was studied. At the low temperature of 150 °C and steam/methanol=1.3, methanol was completely (100%, 13.8 g/h g catalyst) converted to hydrogen and CO 2 without the generation of CO. Within the 60 h catalyst lifespan test, methanol conversion was maintained at 98.6% (13.6 g/h g catalyst) and with 100% CO 2 selectivity. In the meantime, for distinguishing the advantage of nanoscale catalyst, the La 2CuO 4 bulk powder was prepared and tested for the SRM reaction for comparison. Compared with the La 2CuO 4 nanofiber, the bulk powder La 2CuO 4 showed worse catalytic activity for the SRM reaction. The 100% conversion of methanol was achieved at the temperature of 400 °C, with the products being H 2 and CO 2 together with CO. The catalytic activity in terms of methanol conversion dropped to 88.7% (12.2 g/h g catalyst) in 60 h. The reduction temperature for nanofiber La 2CuO 4 was much lower than that for the La 2CuO 4 bulk powder. The nanofibers were of higher specific surface area (105.0 m 2/g), metal copper area and copper dispersion. The in situ FTIR and EPR experiments were employed to study the catalysts and catalytic process. In the nanofiber catalyst, there were oxygen vacancies. H 2-reduction resulted in the generation of trapped electrons [e] on the vacancy sites. Over the nanofiber catalyst, the intermediate H 2CO/HCO was stable and was reformed to CO 2 and H 2 by steam rather than being decomposed directly to CO and H 2. Over the bulk counterpart, apart from the direct decomposition of H 2CO/HCO to CO and H 2, the intermediate H 2COO might go through two decomposition ways: H 2COO=CO+H 2O and H 2COO=CO 2+H 2.

  18. Steam Reforming Technology Demonstration for Conversion of Hanford LAW Tank Waste and LAW Recycle Waste into a Leach Resistant Alkali Aluminosilicate Waste Form

    International Nuclear Information System (INIS)

    As part of the Advanced Remediation Technologies (ART) Program, the Department of Energy (DOE) chose to demonstrate the capabilities of the THORR Steam Reforming process as a potential means to treat and prepare the Hanford Low Activity Waste (LAW) and Low Activity Waste Recycle (LAWR) waste steams for disposal. The Hanford LAW and LAWR waste streams will contain listed and characteristic hazardous waste constituents as well as underlying hazardous constituents that, under federal and state regulations, preclude the wastes from land disposal without treatment. An Engineering Scale Technology Demonstration (ESTD) utilizing the mineralization flowsheet of the THORR process was successfully completed in May 2008 at the Hazen Research facility in Golden, CO, using Hanford LAW and LAWR waste simulants. The Hanford LAW simulant composition was determined by DOE to represent the anticipated stream that would be processed by the Waste Treatment and Immobilization Plant (WTP) LAW melters. The Hanford LAWR stream is based on the anticipated combination of the submerged bed scrubber, the wet electrostatic precipitator, and the caustic scrubber effluents from the WTP LAW melter facility when it is operational. The ESTD clearly demonstrated the capability of the THORR steam reforming process to reliably convert the LAW and LAWR simulants into mineralized solid products in a safe and efficient manner. Gaseous emissions were found to be within regulatory limits for both LAW and LAWR, with the exception of a 1 microgram/dscm exceedance for low volatile metals. The leach performance of the THORR process granular product was superior to the Environmental Assessment (EA) and LAW glass standards for sodium and silicon. Normalized release rates for rhenium (used as a surrogate for technetium) and cesium were much less than that of sodium in the EA and LAW glass standards. Based on data from manual off-gas sampling intervals, cesium and rhenium were captured in the mineralized product

  19. Highly Active and Stable MgAl2O4 Supported Rh and Ir Catalysts for Methane Steam Reforming: A Combined Experimental and Theoretical Study

    Energy Technology Data Exchange (ETDEWEB)

    Mei, Donghai; Glezakou, Vassiliki Alexandra; Lebarbier, Vanessa MC; Kovarik, Libor; Wan, Haiying; Albrecht, Karl O.; Gerber, Mark A.; Rousseau, Roger J.; Dagle, Robert A.

    2014-07-01

    In this work we present a combined experimental and theoretical investigation of stable MgAl2O4 spinel-supported Rh and Ir catalysts for the steam methane reforming (SMR) reaction. Firstly, catalytic performance for a series of noble metal catalysts supported on MgAl2O4 spinel was evaluated for SMR at 600-850°C. Turnover rate at 850°C follows the order: Pd > Pt > Ir > Rh > Ru > Ni. However, Rh and Ir were found to have the best combination of activity and stability for methane steam reforming in the presence of simulated biomass-derived syngas. It was found that highly dispersed ~2 nm Rh and ~1 nm Ir clusters were formed on the MgAl2O4 spinel support. Scanning Transition Electron Microscopy (STEM) images show that excellent dispersion was maintained even under challenging high temperature conditions (e.g. at 850°C in the presence of steam) while Ir and Rh catalysts supported on Al2O3 were observed to sinter at increased rates under the same conditions. These observations were further confirmed by ab initio molecular dynamics (AIMD) simulations which find that ~1 nm Rh and Ir particles (50-atom cluster) bind strongly to the MgAl2O4 surfaces via a redox process leading to a strong metal-support interaction, thus helping anchor the metal clusters and reduce the tendency to sinter. Density functional theory (DFT) calculations suggest that these supported smaller Rh and Ir particles have a lower work function than larger more bulk-like ones, which enables them to activate both water and methane more effectively than larger particles, yet have a minimal influence on the relative stability of coke precursors. In addition, theoretical mechanistic studies were used to probe the relationship between structure and reactivity. Consistent with the experimental observations, our theoretical modeling results also suggest that the small spinel-supported Ir particle catalyst is more active than the counterpart of Rh catalyst for SMR. This work was financially supported by the

  20. Simulation of a compact multichannel membrane reactor for the production of pure hydrogen via steam methane reforming

    Energy Technology Data Exchange (ETDEWEB)

    Vigneault, A.; Grace, J.R. [University of British Columbia, Department of Chemical and Biological Engineering, Vancouver, BC (Canada); Elnashaie, S.S.E.H. [Chemical and Environmental Engineering Department, University Putra Malaysia (UPM), Serdang (Malaysia)

    2012-08-15

    A steady-state 2D model is developed for a multichannel membrane reactor (MCMR) to produce pure hydrogen. The model includes one reforming channel coupled with a PdAg membrane to produce H{sub 2} and one combustion channel to generate the heat needed for the reforming. Both isothermal and non-isothermal simulations are applied in designing a laboratory-scale proof-of-concept reactor. Isothermal sensitivity analysis indicates parameter adjustments practically available to improve reactor performance. In non-isothermal simulations, catalyst layer thickness and kinetic pre-exponential factor are varied along the reactor length. Predictions indicate that the reforming methane conversion increased from 74 % to 91 %, while avoiding hot spots. Compared with other membrane reactors, the MCMR has the potential for one to two orders of magnitude higher H{sub 2} production per reactor volume and per mass of catalyst. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Numerical simulation of competitive aerobic / anaerobic hydrocarbon plume biodegradation in two-dimensional bench scale lab-experiments

    Science.gov (United States)

    Beyer, C.; Ballarini, E.; Bauer, R.; Griebler, C.; Bauer, S.

    2011-12-01

    The biodegradation of oxidizable hydrocarbon contaminants in the subsurface requires the presence of compatible microbial communities as well as sufficient amounts of electron acceptors and nutrients. In this context, transverse mixing, driven by dispersion and diffusion, is one of the main mechanisms governing the availability of dissolved electron acceptors at a hydrocarbon plume fringe. Aerobic and anaerobic biodegradation of hydrocarbons limited by transverse mixing has been studied experimentally in 2D bench-scale flow-through tanks, filled with a saturated porous medium. Flow of groundwater through the tanks was induced by pumping water at one side through injection ports, and simultaneously extracting water at the other side of the tank. An ethylbenzene plume was established by injection through the central inlet port. A mixture of unlabeled and fully deuterium-labeled isotopomers was used in order to investigate the spatial distribution of degradation processes via monitoring of compound-specific stable isotope fractionation. In the first phase of the experiment, aerobic biodegradation was studied. For this purpose, the tank was recharged with water containing oxygen as a dissolved electron acceptor and the aerobic strain Pseudomonas putida F1 was inoculated. Later, nitrate was added to the recharge water as an additional electron acceptor and the denitrifying strain Aromatoleum aromaticum EbN1 was amended to study competitive aerobic/anaerobic biodegradation. A numerical reactive transport model of the experiment was set up for a model based interpretation of the observed degradation patterns. In a sensitivity analysis, the influence of the relevant hydrodynamic parameters on the observable distributions of ethylbenzene isotopomers, oxygen and nitrate was studied. Subsequent model calibration allowed for a good agreement with ethylbenzene concentrations measured at the tank outlet ports as well as oxygen concentrations, which were measured at several

  2. Enhanced removal of VOCs from aquifers during air sparging using thickeners and surfactants: Bench-scale experiments.

    Science.gov (United States)

    Kim, Heonki; Ahn, Dayoung; Annable, Michael D

    2016-01-01

    The effects of controlled air flow paths during air sparging on the removal of volatile organic compounds were examined in this study using a two-dimensional bench-scale physical model. An aqueous solution of sodium carboxymethylcellulose (SCMC), which is a thickener, was used to increase the resistance of water to displacement by injected air in a region around the targeted zone. At the same time, an aqueous solution of sodium dodecylbenzene sulfonate (SDBS), which is a surfactant, was used to reduce the air entry pressure to enhance the air flow through the targeted region. Trichloroethene (TCE), dissolved in water, was used to represent an aqueous phase volatile organic compound (VOC). A binary mixture of perchloroethene (PCE) and n-hexane was also used as a nonaqeous phase liquid (NAPL). Controlled air flow through the source zone, achieved by emplacing a high viscosity aqueous solution into a region surrounding the TCE-impacted zone, resulted in increased TCE removal from 23.0% (control) to 38.2% during a 2.5h period. When the air flow was focused on the targeted source zone of aqueous phase TCE (by decreasing the surface tension within the source zone and its vicinity by 28 dyn/cm, no SCMC applied), the mass removal of TCE was enhanced to 41.3% during the same time period. With SCMC and SDBS applied simultaneously around and beneath a NAPL source zone, respectively, the NAPL components were found to be removed more effectively over a period of 8.2h than the sparging experiment with no additives applied; 84.6% of PCE and 94.0% of n-hexane were removed for the controlled air flow path experiments (with both SCMC and SDBS applied) compared to 52.7% (PCE) and 74.0% (n-hexane) removal for the control experiment (no additives applied). Based on the experimental observations made in this study, applying a viscous aqueous solution around the source zone and a surfactant solution in and near the source zone, the air flow was focused through the targeted contaminant

  3. Permeable Reactive Biobarriers for In Situ Cr(VI) Reduction: Bench Scale Tests Using Cellulomonas sp. Strain ES6

    Energy Technology Data Exchange (ETDEWEB)

    Sridhar Viamajala; Brent M. Peyton; Robin Gerlach; Vaideeswaran; William A. Apel; James N. Petersen

    2008-12-01

    Chromate (Cr(VI)) reduction studies were performed in bench scale flow columns using the fermentative subsurface isolate Cellulomonas sp. strain ES6. In these tests, columns packed with either quartz sand or hydrous ferric oxide (HFO)-coated quartz sand, were inoculated with strain ES6 and fed nutrients to stimulate growth before nutrient-free Cr(VI) solutions were injected. Results show that in columns containing quartz sand, a continuous inflow of 2 mg/L Cr(VI) was reduced to below detection limits in the effluent for durations of up to 5.7 residence times after nutrient injection was discontinued proving the ability of strain ES6 to reduce chromate in the absence of an external electron donor. In the HFO-containing columns, Cr(VI) reduction was significantly prolonged and effluent Cr(VI) concentrations remained below detectable levels for periods of up to 66 residence times after nutrient injection was discontinued. Fe was detected in the effluent of the HFO-containing columns throughout the period of Cr(VI) removal indicating that the insoluble Fe(III) bearing solids were being continuously reduced to form soluble Fe(II) resulting in prolonged abiotic Cr(VI) reduction. Thus, growth of Cellulomonas within the soil columns resulted in formation of permeable reactive barriers that could reduce Cr(VI) and Fe(III) for extended periods even in the absence of external electron donors. Other bioremediation systems employing Fe(II)-mediated reactions require a continuous presence of external nutrients to regenerate Fe(II). After depletion of nutrients, contaminant removal within these systems occurs by reaction with surface-associated Fe(II) that can rapidly become inaccessible due to formation of crystalline Fe-minerals or other precipitates. The ability of fermentative organisms like Cellulomonas to reduce metals without continuous nutrient supply in the subsurface offers a viable and economical alternative technology for in situ remediation of Cr

  4. Enhanced removal of VOCs from aquifers during air sparging using thickeners and surfactants: Bench-scale experiments

    Science.gov (United States)

    Kim, Heonki; Ahn, Dayoung; Annable, Michael D.

    2016-01-01

    The effects of controlled air flow paths during air sparging on the removal of volatile organic compounds were examined in this study using a two-dimensional bench-scale physical model. An aqueous solution of sodium carboxymethylcellulose (SCMC), which is a thickener, was used to increase the resistance of water to displacement by injected air in a region around the targeted zone. At the same time, an aqueous solution of sodium dodecylbenzene sulfonate (SDBS), which is a surfactant, was used to reduce the air entry pressure to enhance the air flow through the targeted region. Trichloroethene (TCE), dissolved in water, was used to represent an aqueous phase volatile organic compound (VOC). A binary mixture of perchloroethene (PCE) and n-hexane was also used as a nonaqeous phase liquid (NAPL). Controlled air flow through the source zone, achieved by emplacing a high viscosity aqueous solution into a region surrounding the TCE-impacted zone, resulted in increased TCE removal from 23.0% (control) to 38.2% during a 2.5 h period. When the air flow was focused on the targeted source zone of aqueous phase TCE (by decreasing the surface tension within the source zone and its vicinity by 28 dyn/cm, no SCMC applied), the mass removal of TCE was enhanced to 41.3% during the same time period. With SCMC and SDBS applied simultaneously around and beneath a NAPL source zone, respectively, the NAPL components were found to be removed more effectively over a period of 8.2 h than the sparging experiment with no additives applied; 84.6% of PCE and 94.0% of n-hexane were removed for the controlled air flow path experiments (with both SCMC and SDBS applied) compared to 52.7% (PCE) and 74.0% (n-hexane) removal for the control experiment (no additives applied). Based on the experimental observations made in this study, applying a viscous aqueous solution around the source zone and a surfactant solution in and near the source zone, the air flow was focused through the targeted contaminant

  5. Single Step Bi-reforming and Oxidative Bi-reforming of Methane (Natural Gas) with Steam and Carbon Dioxide to Metgas (CO-2H2) for Methanol Synthesis: Self-Sufficient Effective and Exclusive Oxygenation of Methane to Methanol with Oxygen.

    Science.gov (United States)

    Olah, George A; Goeppert, Alain; Czaun, Miklos; Mathew, Thomas; May, Robert B; Prakash, G K Surya

    2015-07-15

    Catalysts based on suitable metal oxide supports, such as NiO/MgO and CoO/MgO, were shown to be active for single step bi-reforming, the combined steam and dry reforming of methane or natural gas with H2O and CO2 exclusively to metgas (CO-2H2) for efficient methanol synthesis. Reactions were carried out in a tubular flow reactor under pressures up to 42 bar at 830-910 °C. Using a CH4 to steam to CO2 ratio of ∼3:2:1 in the gas feed, the H2/CO ratio of 2:1 was achieved, which is desired for subsequent methanol synthesis. The needed 2/1 steam/CO2 feed ratio together with the reaction heat for the endothermic bi-reforming can be conveniently obtained by the complete combustion of a quarter part of the overall used methane (natural gas) with oxygen of the air (oxidative bi-reforming). Complete combustion of a part of methane followed by bi-reforming leads to the production of metgas (H2/CO in 2:1 mol ratio) for self-sufficient exclusive methanol synthesis. The long sought after but elusive efficient and selective oxygenation of methane to methanol is thus achieved in an effective and economic way without any oxidation byproduct formation according to CH4 + 1/2O2 → CH3OH. PMID:26086090

  6. Lunar Organic Waste Reformer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Organic Waste Reformer (LOWR) utilizes high temperature steam reformation to convert all plastic, paper, and human waste materials into useful gases. In...

  7. Boiling heat transfer in a bench-scale molten-salt thermal energy storage device. [NaNO/sub 3/

    Energy Technology Data Exchange (ETDEWEB)

    Canon, R.M.; Hewitt, J.D.

    1977-05-01

    Overall boiling heat transfer coefficients were determined experimentally for a proposed Thermal Energy Storage (TES) salt (NaNO/sub 3/) in a vertical-tube boiler for the following range of variables: (1) water flow = 840 to 2800 lb/h/ft/sup 2/; (2) Steam temp. = 295 to 475/sup 0/F; (3) steam pressure = 50 to 500 psi; and (4) heat flux = 2100 to 6700 Btu/hr/ft/sup 2/. Tube and vessel heat fluxes and energy recovery fractions were also determined.

  8. Activity and stability enhancement of copper-alumina catalysts using cerium and zinc promoters for the selective production of hydrogen via steam reforming of methanol

    Science.gov (United States)

    Patel, Sanjay; Pant, K. K.

    The catalytic activity and hydrogen selectivity of cerium and zinc promoted copper-alumina catalysts have been investigated for the selective production of hydrogen via steam reforming of methanol (SRM). The SRM was carried out in a fixed bed tubular reactor at atmospheric pressure over a temperature range 200-300 °C. The major reaction products were hydrogen and carbon dioxide with traces of carbon monoxide. Catalysts of varying compositions were prepared by the wet impregnation method and characterized by atomic absorption spectroscopy (AAS), BET surface area, pore volume, pore size, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and thermogravimetry analysis (TGA). Results revealed that the methanol conversion, hydrogen selectivity and carbon monoxide formation varied with the type of promoter and content of copper in the catalyst. Cerium promoted Cu-Zn-Ce-Al-oxide catalysts improved the activity and hydrogen selectivity greatly and also kept the CO formation very low. Using cerium the SRM could be carried out at lower temperature with high methanol conversion, results in suppression of methanol decomposition and reverse water gas shift reactions eventually end-up with the low carbon monoxide and hydrogen rich product stream. Cerium also stabilizes the copper-alumina catalysts effectively that was confirmed by deactivation studies in which cerium promoted Cu-Zn-Ce-Al-oxide catalysts gave the consistent performance for a long run-time compared to catalysts containing only zinc promoter. The optimum operating conditions for SRM have been investigated by detailed study of effects of reaction temperature, contact time and steam to methanol molar ratio on methanol conversion, hydrogen selectivity and CO formation. Reaction pathway has been proposed for the SRM based on results obtained.

  9. Enhancement of Glycerol Steam Reforming Activity and Thermal Stability by Incorporating CeO2 and TiO2 in Ni- and Co-MCM-41 Catalysts

    Science.gov (United States)

    Dade, William N.

    Hydrogen (H2) has many applications in industry with current focus shifted to production of hydrocarbon fuels and valuable oxygenates using the Fischer-Tropsch technology and direct use in proton exchange membrane fuel cell (PEMFC). Hydrogen is generally produced via steam reforming of natural gas or alcohols like methanol and ethanol. Glycerol, a by-product of biodiesel production process, is currently considered to be one of the most attractive sources of sustainable H2 due to its high H/C ratio and bio-based origin. Ni and Co based catalysts have been reported to be active in glycerol steam reforming (GSR); however, deactivation of the catalysts by carbon deposition and sintering under GSR operating conditions is a major challenge. In this study, a series of catalysts containing Ni and Co nanoparticles incorporated in CeO2 and TiO2 modified high surface area MCM-41 have been synthesized using one-pot method. The catalysts are tested for GSR (at H2O/Glycerol mole ratio of 12 and GHSV of 2200 h-1) to study the effect of support modification and reaction temperature (450 - 700 °C) on the product selectivity and long term stability. GSR results revealed that all the catalysts performed significantly well exhibiting over 85% glycerol conversion at 650 °C except Ni catalysts that showed better low temperature activities. Deactivation studies of the catalysts conducted at 650 °C indicated that the Ni-TiO2-MCM-41 and Ni-CeO 2-MCM-41 were resistant to deactivation with ˜100% glycerol conversion for 40 h. In contrast, Co-TiO2-MCM-41 perform poorly as the catalyst rapidly deactivated after 12 h to yield ˜20% glycerol conversion after 40 h. The WAXRD and TGA-DSC analyses of spent catalysts showed a significant amount of coke deposition that might explain catalysts deactivation. The flattening shape of the original BET type IV isotherm with drastic reduction of catalyst surface area can also be responsible for observed drop in catalysts activities.

  10. Hydrogen Production via a High-Efficiency Low-Temperature Reformer

    Energy Technology Data Exchange (ETDEWEB)

    Paul KT Liu; Theo T. Tsotsis

    2006-05-31

    Fuel cells are promoted by the US government as a viable alternative for clean and efficient energy generation. It is anticipated that the fuel cell market will rise if the key technical barriers can be overcome. One of them is certainly fuel processing and purification. Existing fuel reforming processes are energy intensive, extremely complicated and capital intensive; these disadvantages handicap the scale-down of existing reforming process, targeting distributed or on-board/stationary hydrogen production applications. Our project involves the bench-scale demonstration of a high-efficiency low-temperature steam reforming process. Hydrogen production can be operated at 350 to 400ºC with our invention, as opposed to >800ºC of existing reforming. In addition, our proposed process improves the start-up deficiency of conventional reforming due to its low temperature operation. The objective of this project is to demonstrate the invented process concept via a bench scale unit and verify mathematical simulation for future process optimization study. Under this project, we have performed the experimental work to determine the adsorption isotherm, reaction kinetics, and membrane permeances required to perform the process simulation based upon the mathematical model developed by us. A ceramic membrane coated with palladium thin film fabricated by us was employed in this study. The adsorption isotherm for a selected hydrotalcite adsorbent was determined experimentally. Further, the capacity loss under cyclic adsorption/desorption was confirmed to be negligible. Finally a commercial steam reforming catalyst was used to produce the reaction kinetic parameters required for the proposed operating condition. With these input parameters, a mathematical simulation was performed to predict the performance of the invented process. According to our simulation, our invented hybrid process can deliver 35 to 55% methane conversion, in comparison with the 12 and 18-21% conversion of

  11. Progresses in Catalytic Steam Reforming of Bio-oil for Hydrogen Production%生物油水蒸气催化重整制氢研究进展

    Institute of Scientific and Technical Information of China (English)

    张文涛; 陈明强; 刘少敏; 杨忠连

    2014-01-01

    氢气作为一种环境友好的清洁能源,人们对它的关注度越来越高。生物油水蒸气催化重整制氢是未来制氢的一种可行性方案。本文综述了近年来生物油水蒸气重整制氢的研究进展。主要从重整制氢反应机理、热力学分析、催化重整催化剂、代表性的重整反应器方面进行讨论,指出催化重整中的主要问题是碳沉积导致催化剂失活。研制高活性、高稳定性、高选择性的催化剂是生物油催化重整制氢的关键。%Hydrogen is regarded as an environmentally friendly clean energy and has been paid more and more attention. Catalytic steam reforming of bio-oil is a feasible solution for future hydrogen production. The recent progress of catalytic steam reforming of bio-oil for hydrogen production was reviewed in this paper. Some respects such as reaction mechanism, thermodynamic analysis, catalysts, and typical reactors of catalytic steam reforming of bio-oil were discussed. The deactivation of catalyst caused by carbon deposition is pointed out as the main problem during the reforming process. Therefore, the key factor of catalytic reforming of bio-oil is to develop high activity, high stability, and high selectivity catalysts.

  12. Effect of Ni Loading and CexZr1-xO2 Promoter on Ni-Based SBA-15 Catalysts for Steam Reforming of Methane

    Institute of Scientific and Technical Information of China (English)

    Huijun Wan; Xiujin Li; Shengfu Ji; Bingyao Huang; Kai Wang; Chengyue Li

    2007-01-01

    A series of Ni/SBA-15 catalysts with Ni contents ranging from 5wt% to 20wt% as well as 10wt%Ni/10wt%CexZr1-xO2/SBA-15 (x=0, 0.5, 1) were prepared. The structures of the catalysts were characterized using XRD, TPR, TEM and BET techniques. The catalytic activities of the catalysts for steam reforming of methane were evaluated in a continuous flow microreactor. The results indicated that both the Ni/SBA-15 and the Ni/CexZr1-xO2/SBA-15 catalysts had good catalytic activities at atmospheric pressure. The 10wt%Ni/SBA-15 catalyst exhibited excellent stability at 800 ℃ for time on stream of 740 h. After the reaction, carbon deposits were not formed on the surface of the catalyst. There existed a regular hexagonal mesoporous structure in the Ni/SBA-15 and the Ni/CexZr1-xO2/SBA-15 catalysts. The nickel species and the CexZr1-xO2 component were all confined in the SBA-15 mesopores.The CexZr1-xO2 could promote dispersion of the nickel species in the Ni/CexZr1-xO2/SBA-15 catalysts.

  13. Hydrogen and syngas production from two-step steam reforming of methane over CeO2-Fe2O3 oxygen carrier

    Institute of Scientific and Technical Information of China (English)

    ZHU

    2010-01-01

    Two-step steam reforming of methane(SRM)is a novel chemical looping process towards the production of pure hydrogen and syngas(synthesis gas),consisting ofa syngas production step and a water-splitting step.Renewable energy can be used to drive this process for hydrogen production,especially solar energy.CeO2-Fe2O3 complex oxide oxygen carrier was prepared by the impregnation method and characterized by means of X-ray diffractometer(XRD),Raman spectroscopy(Raman)and hydrogen programmed reduction(H2-TPR).CH4temperature programmed and isothermal reactions were adopted to test syngas production reactivity,and water splitting reaction was employed to investigate water-splitting activity.Moreover,two-step SRM performance was evaluated by a successive redox cycle.The results showed that CO-uncontaminated H2 and highly selective syngas(with H2/CO ratio close to 2)could be respectively obtained from two steps,and CeFeO3 formation was found in the first redox cycle and proved to be enhanced by the redox treatment.After 10 successive cycles,obvious CeFeO3 phase was detected,which may be responsible for favorable successive redox cycle performances.

  14. Methanol-steam reforming using a microstructured reactor for hydrogen generation for fuel cell powered vehicles; Methanol-Dampf Reformierung im Mikrostrukturreaktor zur Wasserstofferzeugung fuer Brennstoffzellenfahrzeuge

    Energy Technology Data Exchange (ETDEWEB)

    Pfeifer, P.

    2003-08-01

    On-board hydrogen production in automotive systems is of great interest in order to fulfil the legal requirements of emission control in the near future and to produce zero emission cars. The demand of high dynamics of the on-board hydrogen generation leads to newer technologies like microreaction technology. Excellent heat and mass transfer in microstructured reactors/heat exchangers increase the possibility to reduce the system size and to decrease parasitic heat loss, additionally. The present work describes the development of a coating technology, a catalyst system, catalyst characterisation and the test of these catalysts considering modelling of the reaction and scale-up of metallic microreactors for the catalytic steam reforming of methanol. The appropriateness of the catalyst coatings and of the metallic microreactors for the chosen reaction and dynamic operation has been demonstrated successfully. The coating of the metallic microchannels in the diameter range 100-300 {mu}m was done by the modification of the conventional washcoating process using a solvent-polymer-nanoparticle slurry. Pre-Coating (coating before assembling the foils to a reactor) and Post-Coating (coating after assembling the microstructured foils to a reactor) were shown to be feasible, which is an important fact considering the assembling procedure. Homogeneity of the coating was proven experimentally by hot wire anemometry. (orig.)

  15. Radioactive Demonstration Of Mineralized Waste Forms Made From Hanford Low Activity Waste (Tank SX-105 And AN-103) By Fluidized Bed Steam Reformation

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, Carol; Herman, Connie; Crawford, Charles; Bannochie, Christopher; Burket, Paul; Daniel, Gene; Cozzi, Alex; Nash, Charles; Miller, Donald; Missimer, David

    2014-01-10

    One of the immobilization technologies under consideration as a Supplemental Treatment for Hanford’s Low Activity Waste (LAW) is Fluidized Bed Steam Reforming (FBSR). The FBSR technology forms a mineral waste form at moderate processing temperatures thus retaining and atomically bonding the halides, sulfates, and technetium in the mineral phases (nepheline, sodalite, nosean, carnegieite). Additions of kaolin clay are used instead of glass formers and the minerals formed by the FBSR technology offers (1) atomic bonding of the radionuclides and constituents of concern (COC) comparable to glass, (2) short and long term durability comparable to glass, (3) disposal volumes comparable to glass, and (4) higher Na2O and SO{sub 4} waste loadings than glass. The higher FBSR Na{sub 2}O and SO{sub 4} waste loadings contribute to the low disposal volumes but also provide for more rapid processing of the LAW. Recent FBSR processing and testing of Hanford radioactive LAW (Tank SX-105 and AN-103) waste is reported and compared to previous radioactive and non-radioactive LAW processing and testing.

  16. Influence of Ce-precursor and fuel on structure and catalytic activity of combustion synthesized Ni/CeO{sub 2} catalysts for biogas oxidative steam reforming

    Energy Technology Data Exchange (ETDEWEB)

    Vita, Antonio, E-mail: antonio.vita@itae.cnr.it; Italiano, Cristina; Fabiano, Concetto; Laganà, Massimo; Pino, Lidia

    2015-08-01

    A series of nanosized Ni/CeO{sub 2} catalysts were prepared by Solution Combustion Synthesis (SCS) varying the fuel (oxalyldihydrazide, urea, carbohydrazide and glycerol), the cerium precursor (cerium nitrate and cerium ammonium nitrate) and the nickel loading (ranging between 3.1 and 15.6 wt%). The obtained powders were characterized by X-ray Diffraction (XRD), N{sub 2}-physisorption, CO-chemisorption, Temperature Programmed Reduction (H{sub 2}-TPR) and Scanning Electron Microscopy (SEM). The catalytic activity towards the Oxy Steam Reforming (OSR) of biogas was assessed. The selected operating variables have a strong influence on the nature of combustion and, in turn, on the morphological and structural properties of the synthesized catalysts. Particularly, the use of urea allows to improve nickel dispersion, surface area, particle size and reducibility of the catalysts, affecting positively the biogas OSR performances. - Highlights: • Synthesis of Ni/CeO{sub 2} nanopowders by quick and easy solution combustion synthesis. • The fuel and precursor drive the structural and morphological properties of the catalysts. • The use of urea as fuel allows to improve nickel dispersion, surface area and particle size. • Ni/CeO{sub 2} (7.8 wt% of Ni loading) powders synthesized by urea route exhibits high performances for the biogas OSR process.

  17. Low temperature steam reforming of ethanol for carbon monoxide-free hydrogen production over mesoporous Sn-incorporated SBA-15 catalysts

    International Nuclear Information System (INIS)

    This study investigated the application of a new metal catalytic species, Sn ion, rather than conventional Ni-based catalyst, to hydrogen production from ESR (ethanol steam reforming). Mesoporous SBA-15 catalysts with various contents of incorporated Sn (Sn-SBA-15) exhibited significantly higher ESR reactivity and the highest reactivity was achieved with 20 mol% Sn-SBA-15 catalysts: the H2 production and ethanol conversion were maximized at 75% and 92%, respectively, at a mild temperature of 500 °C for 1 h at a CH3CH2OH:H2O ratio of 1:1 and a GHSV (gas hourly space velocity) of 6600 h−1. The XRD (X-ray diffraction) and XPS (X-ray photoelectron spectroscopy) results indicated that the incorporated Sn species, SnO2/Sn, was simultaneously transferred to Sn/SnO2 by alternating their redox reactions and that the reactivity of the Sn-based activity could be long-lasting. -- Highlights: ► Mesoporous SBA-15 catalysts with various contents of incorporated Sn (Sn-SBA-15) exhibited significantly higher ESR reactivity. ► The H2 production and ethanol conversion were maximized at 75% and 92% over 20-mol% Sn-SBA-15 catalysts. ► The reactivity of the Sn-based activity could be long-lasting.

  18. Modeling Open-Flow Steam Reforming of Methanol over Cu/ZnO/Al2O3 Catalyst in an Axisymmetric Reactor

    Directory of Open Access Journals (Sweden)

    Leonardo Pacheco

    2015-01-01

    Full Text Available This paper describes a CFD study of the steam-reforming process (SRP of methanol in a short pseudo-contact time reactor of fixed bed type, in axi-symmetric conditions. The SRP is important sake for hydrogen production, and the design /scale-up/control of the industrial processes in the future are supported by a reliable knowledge and prediction of the catalytic reaction. The difficulty of determining the reaction scheme and the associated constants is wellknown, due to the necessity of identifying the reaction kinetics in purely chemical regime, meaning with a perfect homogeneity and flow independence. Practically these ideal conditions, albeit assumed, are not fulfilled so that the intrinsic chemical kinetics is not reached. For the case of SRP, we have attempted here to validate the Peppley’s model by a numerical modelling reproducing exactly the local conditions in the experimental duct, accounting for gradients in the cross section. The numerical results show the same trends than the experimental one, but with a slight shift of 20% as a consequence of the reactor heterogeneity. This result seems acceptable to validate the use of the Peepley’s model for further studies in other types of complex flow reactors.

  19. Radioactive Demonstration Of Mineralized Waste Forms Made From Hanford Low Activity Waste (Tank SX-105 And AN-103) By Fluidized Bed Steam Reformation

    International Nuclear Information System (INIS)

    One of the immobilization technologies under consideration as a Supplemental Treatment for Hanford's Low Activity Waste (LAW) is Fluidized Bed Steam Reforming (FBSR). The FBSR technology forms a mineral waste form at moderate processing temperatures thus retaining and atomically bonding the halides, sulfates, and technetium in the mineral phases (nepheline, sodalite, nosean, carnegieite). Additions of kaolin clay are used instead of glass formers and the minerals formed by the FBSR technology offers (1) atomic bonding of the radionuclides and constituents of concern (COC) comparable to glass, (2) short and long term durability comparable to glass, (3) disposal volumes comparable to glass, and (4) higher Na2O and SO4 waste loadings than glass. The higher FBSR Na2O and SO4 waste loadings contribute to the low disposal volumes but also provide for more rapid processing of the LAW. Recent FBSR processing and testing of Hanford radioactive LAW (Tank SX-105 and AN-103) waste is reported and compared to previous radioactive and non-radioactive LAW processing and testing

  20. Co/Mg/Al hydrotalcite-type precursor, promoted with La and Ce, studied by XPS and applied to methane steam reforming reactions

    International Nuclear Information System (INIS)

    Catalysts' precursor of Co/Mg/Al promoted with Ce and La were tested in the steam reforming of methane (SRM). The addition of promoters was made by anion-exchange. The oxides characterization was made by X-ray Photoelectron Spectroscopy (XPS) analysis that confirmed Co2+ species in free form on surface and interacted with Mg and Al in the form of solid solution. In the SRM with high fed molar ratio of H2O:CH4 = 4:1, the catalysts showed a great affinity with water and immediately deactivated by oxidation of the active sites. In the stoichiometric ratio of H2O:CH4 = 2:1 the catalysts were active and presented low carbon deposition during the time reaction tested. Also a test with low fed molar ratio H2O:CH4 = 0.5:1 was carried out to evaluate the stability of the catalysts by CH4 decomposition and all the catalysts were stable during 6 h of reaction. Promoted catalysts presented lower carbon deposition