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Aspen Process Flowsheet Simulation Model of a Battelle Biomass-Based Gasification, Fischer-Tropsch Liquefaction and Combined-Cycle Power Plant

Description: This study was done to support the research and development program of the National Renewable Energy Laboratory (NREL) in the thermochemical conversion of biomass to liquid transportation fuels using current state-of-the-art technology. The Mitretek study investigated the use of two biomass gasifiers; the RENUGAS gasifier being developed by the Institute of Gas Technology, and the indirectly heated gasifier being developed by Battelle Columbus. The Battelle Memorial Institute of Columbus, Ohio indirectly heated biomass gasifier was selected for this model development because the syngas produced by it is better suited for Fischer-Tropsch synthesis with an iron-based catalyst for which a large amount of experimental data are available. Bechtel with Amoco as a subcontractor developed a conceptual baseline design and several alternative designs for indirect coal liquefaction facilities. In addition, ASPEN Plus process flowsheet simulation models were developed for each of designs. These models were used to perform several parametric studies to investigate various alternatives for improving the economics of indirect coal liquefaction.
Date: October 30, 1998
Partner: UNT Libraries Government Documents Department

Chemistry of thermochemical cycles from U. S. A. programs. [Review of ERDA-sponsored work]

Description: Theoretical advantages for hydrogen production by thermochemical methods have stimulated many efforts to ''invent,'' test and/or perform engineering and economic evaluation of thermochemical processes. A large number of thermochemical cycles have been conceived. Unfortunately, many have been published without experimental verification of the reactions in the cycle. As a result of this, most evaluations and/or comparisons of thermochemical processes for process efficiency or cost have been based on assumed data for fictitious cycles. In the United States, experimental and theoretical programs to develop or evaluate thermochemical processes are being conducted in several ERDA laboratories and in some commercial laboratories. Supporting research in thermochemistry, reaction kinetics and chemical engineering is also supported in universities. From these programs it has become painfully clear that very few conceptual cycles survive experimental testing. Nevertheless, these programs have developed thermochemical cycles where all reactions have been demonstrated in the laboratory. Most of these have been described in recent publications. In this paper, experimentally valid cycles are identified and described. These involve different chemical systems for which thermochemical data are usually available. This implies that additional (better) cycles will be found. Common problems of most cycles include: (1) manipulations involving solids; (2) drying large volumes of solutions; (3) reactions where heat must be transferred to a solid from a heat exchanger surface. It seems clear that engineering assessment of such problems in specific cycles could lead to variations that improve the process. This feed-back procedure might produce a practical process.
Date: January 1, 1976
Creator: Bowman, M. G.
Partner: UNT Libraries Government Documents Department

Thermochemical water-splitting cycle, bench-scale investigations, and process engineering. Final report, February 1977-December 31, 1981

Description: The sulfur-iodine water-splitting cycle is characterized by the following three reactions: 2H/sub 2/O + SO/sub 2/ + I/sub 2/ ..-->.. H/sub 2/SO/sub 4/ + 2HI; H/sub 2/SO/sub 4/ ..-->.. H/sub 2/O + SO/sub 2/ + 1/2 O/sub 2/; and 2HI ..-->.. H/sub 2/ + I/sub 2/. This cycle was developed at General Atomic after several critical features in the above reactions were discovered. These involved phase separations, catalytic reactions, etc. Estimates of the energy efficiency of this economically reasonable advanced state-of-the-art processing unit produced sufficiently high values (to approx.47%) to warrant cycle development effort. The DOE contract was largely directed toward the engineering development of this cycle, including a small demonstration unit (CLCD), a bench-scale unit, engineering design, and costing. The work has resulted in a design that is projected to produce H/sub 2/ at prices not yet generally competitive with fossil-fuel-produced H/sub 2/ but are projected to be favorably competitive with respect to H/sub 2/ from fossil fuels in the future.
Date: May 1, 1982
Creator: Norman, J.H.; Besenbruch, G.E.; Brown, L.C.; O'Keefe, D.R. & Allen, C.L.
Partner: UNT Libraries Government Documents Department

HYDRGN - a computerized technique for the analysis of thermochemical water-splitting cycles

Description: The HYDRGN computer program was designed to analyze closed thermochemical cycles for the production of hydrogen from water. This report includes the basic theory, assumptions, and methods of calculation used in this analysis along with a description of the program and its use. The source program and necessary data bank are available from the University of Kentucky. These may be obtained by sending a magnetic tape (minimum length 1200 ft) and a written request specifying the type of computer and recording characteristics of the tape. A small fee is charged for the recording and handling of the tape.
Date: June 1, 1977
Creator: Carty, R. H.; Conger, W. L.; Funk, J. E. & Barker, R.
Partner: UNT Libraries Government Documents Department

Cadmium-cadmium carbonate cycle for the thermochemical production of hydrogen

Description: A means of thermally decomposing water using cadmium, cadmium oxide and cadmium carbonate is described. Experimental emphasis is placed on the hydrogen producing step which consists of reacting cadmium with water and carbon dioxide to produce cadmium carbonate and hydrogen. The cycle is completed by decomposing the carbonate, first to the oxide, and then to the metal. Laboratory studies show that hydrogen is evolved slowly in relatively high yields (57 to 65%), but, when produced in the presence of ammonium chloride, both the yield and rate are increased (72% in 0.5 hr). The figure of merit of the cycle is 78% with a probability of some decrease resultant from the ammonium chloride reaction.
Date: January 1, 1980
Creator: Mason, C.F.V. & Bowman, M.G.
Partner: UNT Libraries Government Documents Department

Possible thermochemical cycle based on methanol. [Tetramethylphosphine]

Description: The production of hydrogen from methanol is of particular interest since the two reactions: CH/sub 4/ + H/sub 2/O + CO + 3H/sub 2/ and CO + 2H/sub 2/ = CH/sub 3/OH are individually well known industrial processes. Thus, if a method can be found to obtain the overall reaction: CH/sub 3/OH = CH/sub 4/ + 1/2 O/sub 2/ then, in total, a cyclic water splitting process is complete for which much of the industrial development is already known. A possible method is through the use of trimethylphosphine. This reacts with methanol to form a salt, tetramethyl phosphonium hydroxide: CH/sub 3/OH + (CH/sub 3/)/sub 3/P = (CH/sub 3/)/sub 4/POH. Tetramethylphosphonium hydroxide gives methane and trimethylphosphine oxide very readily: (CH/sub 3/)/sub 4/POH = CH/sub 4/ + (CH/sub 3/)/sub 3/PO. When anhydrous takes place readily at room temperature, but in the presence of water, the rate is retarded. In summary, the overall reaction can be written as: CH/sub 3/OH + (CH/sub 3/)/sub 3/P = CH/sub 4/ + (CH/sub 3/)/sub 3/PO. Thus, provided a way of removing oxygen from trimethylphosphine oxide can be found, (CH/sub 3/)/sub 3/PO = (CH/sub 3/)/sub 3/P + 1/2 O/sub 2/ is a simple method of converting methanol to methane and oxygen.
Date: January 1, 1982
Creator: Mason, C.F.V.
Partner: UNT Libraries Government Documents Department

Preliminary flow sheet and process design for ZnSe thermochemical cycle

Description: A preliminary design of the ZnSe cycle for thermochemical hydrogen production has been prepared for use in deriving economic costs for hydrogen production. The process flowsheet identifies key equipment items as well as major streams. Flow and heat loads have been estimated based on one mole of hydrogen output. The thermal efficiency of this cycle depends on two factors: (1) the ability to perform the dissolution of ZnSO/sub 4/ and the hydrolysis of ZnSe with a minimum amount of aqueous HCl, and (2) the ability to match the process heat requirements with available heat from the exothermic steps in the cycle. Estimates of the cycle's thermal efficiency range from 34--57 percent depending upon the process heat utilization.
Date: June 21, 1976
Creator: Otsuki, H. H. & Cox, K. E.
Partner: UNT Libraries Government Documents Department

Equilibrium effects in high-pressure hydrogen production from thermochemical water-splitting cycles

Description: When hydrogen comes into widespread use as a supplemental fuel, a chemical feedstock, and a primary, future energy carrier, it must be available at pressures of the order of 50 atmospheres. Existing studies of hydrogen transmission indicate that pipeline pressures of 50 to 100 atmospheres will yield an energy carrier system with better cost-effectiveness than underground transmission of electricity. Because high capacity hydrogen compressors have a low compression ratio, high supply pressures are required. This requirement will affect product separations steps and process heat load-line matching. The hydrogen production steps of a large number of projected water-splitting cycles were classified according to whether the sum of the mole numbers of gaseous products is larger or smaller than the sum of the mole numbers of gaseous reactants. When product mole numbers are larger, the hydrogen production step occurs at relatively high temperatures (about 600/sup 0/C or higher). When reactant mole numbers are larger, the required temperature is generally low (about 300/sup 0/C or lower). There were few exceptions, though some water-splitting cycles based on organic chemical reactions fit into a temperature range between these two categories. A group of generalized relationships are presented for hydrogen production steps such that ..delta..G, the Gibb's free energy change for the reaction, is zero. For equilibria favored by, and not favored by pressure, a series of relationships between the hydrogen mole fraction and product pressure can be defined. The trade-offs between product stream composition and input heat temperature can be assessed. The degree to which feed stream impurities can be tolerated, given fixed operating variables, can also be determined.
Date: January 1, 1978
Creator: Schreiber, J. D.; Dafler, J. R. & Foh, S. E.
Partner: UNT Libraries Government Documents Department

BioFacts: Fueling a stronger economy, Thermochemical conversion of biomass

Description: A primary mission of the US DOE is to stimulate the development, acceptance, and use of transportation fuels made from plants and wastes called biomass. Through the National Renewable Energy Laboratory (NREL), Doe is developing and array of biomass conversion technologies that can be easily integrated into existing fuel production and distribution systems. The variety of technology options being developed should enable individual fuel producers to select and implement the most cost-effective biomass conversion process suited to their individual needs. Current DOE biofuels research focuses on the separate and tandem uses of biochemical and thermochemical conversion processes. This overview specifically addresses NREL`s thermochemical conversion technologies, which are largely based on existing refining processes.
Date: December 1, 1994
Partner: UNT Libraries Government Documents Department

Hydrogen from renewable resources. Monthly progress report, February 1996

Description: This month, further progress in the design and fabrication of the new reactor/feeder was achieved. High-pressure gas separation was explored further, and some supplemental experiments on activated carbon production and carbon gasification characteristics in supercritical water were carried out.
Date: March 8, 1996
Creator: Rocheleau, R.E.
Partner: UNT Libraries Government Documents Department

Development of an advanced continuous mild gasification process for the production of coproducts

Description: Western Research Institute (WRI) teamed with the AMAX Research and Development Center and Riley Stoker Corporation on Development of an Advanced, Continuous Mild-Gasification Process for the Production of Coproducts under contract DE-AC21-87MC24268 with the Morgantown Energy Technology of the US Department of Energy. The strategy for this project is to produce electrode binder pitch and diesel fuel blending stock by mild gasification of Wyodak coal. The char is upgraded to produce anode-grade carbon, carbon black, and activated carbon. This report describes results of mild-gasification tests conducted by WRI. Char upgrading tests conducted by AMAX will be described in a separate report.
Date: December 1, 1990
Creator: Merriam, N.W.; Cha, C.Y.; Kang, T.W. & Vaillancourt, M.B.
Partner: UNT Libraries Government Documents Department

Capabilities to Support Thermochemical Hydrogen Production Technology Development

Description: This report presents the results of a study to determine if Idaho National Laboratory (INL) has the skilled staff, instrumentation, specialized equipment, and facilities required to take on work in thermochemical research, development, and demonstration currently being performed by the Nuclear Hydrogen Initiative (NHI). This study outlines the beneficial collaborations between INL and other national laboratories, universities, and industries to strengthen INL's thermochemical efforts, which should be developed to achieve the goals of the NHI in the most expeditious, cost effective manner. Taking on this work supports INL's long-term strategy to maintain leadership in thermochemical cycle development. This report suggests a logical path forward to accomplish this transition.
Date: May 1, 2009
Creator: Ginosar, Daniel M.
Partner: UNT Libraries Government Documents Department

Synfuels from fusion: producing hydrogen with the Tandem Mirror Reactor and thermochemical cycles

Description: This volume contains the following sections: (1) the Tandem Mirror fusion driver, (2) the Cauldron blanket module, (3) the flowing microsphere, (4) coupling the reactor to the process, (5) the thermochemical cycles, and (6) chemical reactors and process units. (MOW)
Date: January 21, 1981
Creator: Werner, R.W. & Ribe, F.L.
Partner: UNT Libraries Government Documents Department

Thermochemical processes for hydrogen production by water decomposition. Progress report, April 1--December 31, 1975

Description: The interest in hydrogen as a chemical feedstock and as a possible non-polluting fuel has continued to be high, affected by recent estimates of 1980 prices for imported natural gas in the range of $3.00/MM Btu. Our exhaustive survey of multi-step thermochemical and hybrid cycles concluded that the most promising prospects to date are (1) a modification of Abraham's ANL-4 cycle, and (2) the Rohm and Haas multi-reaction, single reactor cycle. Both sequences utilize iodine-based oxidation-reduction chemistry and each ultimately produces hydrogen via an iodide vapor decomposition, in the first case from NH/sub 4/I, in the second from HI. Process feasibility depends on demonstration of separation steps of relatively low energy requirements. Further research is proposed along four lines: (1) modeling and computation focusing on selectivity in gas-solid reactions, (2) experimental studies of solids flow and mixing, as well as mass transfer and chemical reaction in rotating and/or oscillating kiln reactors, (3) kinetics of the crucial reactions in the ANL-4 and Rohm and Haas cycles, and gas separations associated with these processes, and (4) flow sheet evaluations and preliminary economics.
Date: December 1, 1975
Creator: Perlmutter, D.D. & Myers, A.L.
Partner: UNT Libraries Government Documents Department

Synfuel (hydrogen) production from fusion power

Description: A potential use of fusion energy for the production of synthetic fuel (hydrogen) is described. The hybrid-thermochemical bismuth-sulfate cycle is used as a vehicle to assess the technological and economic merits of this potential nonelectric application of fusion power.
Date: January 1, 1979
Creator: Krakowski, R.A.; Cox, K.E.; Pendergrass, J.H. & Booth, L.A.
Partner: UNT Libraries Government Documents Department

Two bismuth sulfate-sulfuric acid hybrid thermochemical hydrogen cycles. Some experimental work related to the cycles and their possible improvement. Outline of a proposed antimonyl sulfate cycle in which sulfur dioxide and oxygen are separately evolved

Description: Thermochemical hydrogen production topics discussed include: equilibrium pressures in the decomposition of Bi/sub 2/(SO/sub 4/)/sub 3/ and ..cap alpha..-and ..beta..-Bi/sub 2/O(SO/sub 4/)/sub 2/; survey experiments on the thermal decomposition of Bi/sub 2/(SO/sub 4/)/sub 3/; hydrates sorption of H/sub 2/SO/sub 4/ solutions by the solids; and possible simplification of the SO/sub 3/-SO/sub 2/-O/sub 2/ separation problem with a sulfuric acid-antimonyl sulfate hybrid cycle.
Date: January 1, 1982
Creator: Jones, W.M.
Partner: UNT Libraries Government Documents Department

Utilization of solar thermal sources for thermochemical hydrogen production

Description: The utilization of high temperature solar heat for the production of electricity and/or fuels is a popular concept. However, since solar concentrator systems are expensive and solar radiation intermittent, practical utilization requires processes that exhibit high conversion efficiencies and also incorporate energy storage. The production of hydrogen fulfills the requirement for energy storage and can fulfill the requirement for efficient heat utilization if thermochemical cycles are developed where the temperature and heat requirements of the process match the heat delivery characteristics of the solar receiver system. Cycles based on solid sulfate decomposition reactions may lead to efficient utilization of solar heat at practical temperatures. Higher temperature cycles involving oxide decomposition may also become feasible.
Date: January 1, 1980
Creator: Bowman, M.G.
Partner: UNT Libraries Government Documents Department

LASL thermochemical hydrogen program status on October 31, 1977. [Cycles using sulfuric acid as an intermdiate]

Description: The LASL Hydrogen Program is continuing its investigation of practical schemes to decompose water thermochemically for hydrogen production. Efforts were and are being devoted to process improvements in cycles that use sulfuric acid as an intermediate. Sulfuric acid-hydrogen bromide cycles are being studied as a means of overcoming the heat penalty in drying acid solutions. An alternate approach involves the use of insoluble bismuth sulfate that is precipitated from acid solution. Preliminary energy balances indicate a significant increase in cycle efficiency for both these options.
Date: January 1, 1977
Creator: Cox, K.E. & Bowman, M.G.
Partner: UNT Libraries Government Documents Department

LASL thermochemical hydrogen status on September 30, 1979

Description: The work described in this report was accomplished during the period October 1, 1978 to September 30, 1979. Most of the effort was applied to a study of the Los Alamos Scientific Laboratory (LASL) hybrid bismuth sulfate cycle. The work included a conceptual design of the cycle and experimental work to verify the design conditions. Key findings were: a 50.8% efficiency was obtained when an improved cycle design was coupled to a fusion energy source at 1500 K; experimental results showed an endothermic heat requirement of +172 kJ/mol for the decomposition of Bi/sub 2/O/sub 3/.2SO/sub 3/ to Bi/sub 2/O/sub 3/.SO/sub 3/, and SO/sub 3/; reaction times for bismuth sulfate decomposition were determined as a function of temperature. At 1240 K, < 1.5 min were required for the first two stages of decomposition from Bi/sub 2/O/sub 3/.3SO/sub 3/ to Bi/sub 2/O/sub 3/; tests made to determine the feasibility of decomposing Bi/sub 2/O/sub 3/.2SO/sub 3/ in a 1 inch diameter rotary kiln showed that Bi/sub 2/O/sub 3/.2SO/sub 3/ could be decomposed continuously. In related work, support was given to the DOE Thermochemical Cycle Evaluation Panel (Funk). The Second Annual International Energy Agency (IEA) Workshop on Thermochemical Hydrogen Production from Water met on September 24 to 27, 1979 at Los Alamos.
Date: January 1, 1979
Creator: Cox, K.E.
Partner: UNT Libraries Government Documents Department

LASL bismuth sulfate thermochemical hydrogen cycle

Description: The LASL bismuth sulfate cycle is one of a generic class of solid sulfate cycles in which a metal sulfate is substituted for sulfuric acid in a hybrid (partly electrochemical) cycle. This technique avoids the serious materials and heat penalty problems associated with the handling of concentrated acid solutions, and if the electrolyzer is operated at acid concentrations below 50% it may, in principle, lead to a lower cell voltage with subsequent energy savings. Experiment verification of all steps in the cycle has been obtained, particularly for the decomposition of normal bismuth sulfate and lower bismuth oxysulfates. For the substance, Bi/sub 2/O/sub 3/ 2SO/sub 3/, an endothermic requirement of 172 kJ/mol was obtained, which is considerably less than that for other metal sulfate systems. A rotary kiln was used for continuous experiments and our results show decomposition of this compound to Bi/sub 2/O/sub 3/ SO/sub 3/ in under 8 minutes residence time at 1023 K. Preliminary analysis of the cycle's energy balance shows an overall thermal efficiency of greater than 50% when the maximum cycle reaction temperature is 1500 K. The cycle has potential for hydrogen production when coupled with an energy source such as solar or fusion energy.
Date: January 1, 1980
Creator: Cox, K.E.; Jones, W.M. & Peterson, C.L.
Partner: UNT Libraries Government Documents Department

LASL thermochemical hydrogen program status on September 30, 1980

Description: The work described here was accomplished during the period October 1, 1979-September 30, 1980. Highlights of the experimental program were: a solids decomposition facility was constructed and used to study the handling of bismuth oxysulfates and the kinetics of their decomposition; and the results of our kiln experiments showed that a substantial amount of bismuth oxysulfate decomposition occurs with residence times under 2 min. at temperatures between 973 and 1143/sup 0/K. The LASL bismuth sulfate sub-cycle thus appears a candidate for hydrogen production utilizing a solar heat source. In the evaluation phase of our work, the technoeconomics of the hybrid sulfur cycle were determined and compared with several published results as well as compared to the technoeconomics for water electrolysis processes for hydrogen production. We aided the efforts of the Department of Energy (DOE) Thermochemical Cycle Evaluation Panel in reviewing the Lawrence Livermore Laboratory (LLL) zinc selenide cycle as well as the General Atomic (GA) sulfur-iodine cycle.
Date: January 1, 1980
Creator: Cox, K.E.; Peterson, C.L.; Jones, W.M. & Bowman, M.G.
Partner: UNT Libraries Government Documents Department

Configuring the thermochemical hydrogen sulfuric acid process step for the Tandem Mirror Reactor

Description: This paper identifies the sulfuric acid step as the critical part of the thermochemical cycle in dictating the thermal demands and temperature requirements of the heat source. The General Atomic Sulfur-Iodine Cycle is coupled to a Tandem Mirror. The sulfuric acid decomposition process step is focused on specifically since this step can use the high efficiency electrical power of the direct converter together with the other thermal-produced electricity to Joule-heat a non-catalytic SO/sub 3/ decomposer to approximately 1250/sup 0/K. This approach uses concepts originally suggested by Dick Werner and Oscar Krikorian. The blanket temperature can be lowered to about 900/sup 0/K, greatly alleviating materials problems, the level of technology required, safety problems, and costs. A moderate degree of heat has been integrated to keep the cycle efficiency around 48%, but the number of heat exchangers has been limited in order to keep hydrogen production costs within reasonable bounds.
Date: May 1, 1981
Creator: Galloway, T.R.
Partner: UNT Libraries Government Documents Department