Sample records for biological coal gasification

  1. Solar coal gasification

    Gregg, D. W.; Aiman, W. R.; Otsuki, H. H.; Thorsness, C. B.


    A preliminary evaluation of the technical and economic feasibility of solar coal gasification has been performed. The analysis indicates that the medium-Btu product gas from a solar coal-gasification plant would not only be less expensive than that from a Lurgi coal-gasification plant but also would need considerably less coal to produce the same amount of gas. A number of possible designs for solar coal-gasification reactors are presented. These designs allow solar energy to be chemically stored while at the same time coal is converted to a clean-burning medium-Btu gas.

  2. Development of biological coal gasification (MicGAS Process)


    This report describes progress on three fronts of the project. First in studies to elucidate optimal growing conditions for the consortia of coal degraders employed indicates that best growth occurs with 0. 2% w/v Shefton T. Secondly in comparing the biodegradative properties of the coal degraders, isolates identified as Mic-1 and Mic-4 were the best performers. And lastly bioreactors studies in batch mode are related.

  3. State of the art of biological processes for coal gasification wastewater treatment.

    Zhao, Qian; Liu, Yu


    The treatment of coal gasification wastewater (CGW) poses a serious challenge on the sustainable development of the global coal industry. The CGW contains a broad spectrum of high-strength recalcitrant substances, including phenolic, monocyclic and polycyclic aromatic hydrocarbons, heterocyclic nitrogenous compounds and long chain aliphatic hydrocarbon. So far, biological treatment of CGW has been considered as an environment-friendly and cost-effective method compared to physiochemical approaches. Thus, this reviews aims to provide a comprehensive picture of state of the art of biological processes for treating CGW wastewater, while the possible biodegradation mechanisms of toxic and refractory organic substances were also elaborated together with microbial community involved. Discussion was further extended to advanced bioprocesses to tackle high-concentration ammonia and possible options towards in-plant zero liquid discharge. PMID:27364381

  4. PNNL Coal Gasification Research

    Reid, Douglas J.; Cabe, James E.; Bearden, Mark D.


    This report explains the goals of PNNL in relation to coal gasification research. The long-term intent of this effort is to produce a syngas product for use by internal Pacific Northwest National Laboratory (PNNL) researchers in materials, catalysts, and instrumentation development. Future work on the project will focus on improving the reliability and performance of the gasifier, with a goal of continuous operation for 4 hours using coal feedstock. In addition, system modifications to increase operational flexibility and reliability or accommodate other fuel sources that can be used for syngas production could be useful.

  5. Coal gasification and its applications

    Bell, D.; Towler, B.


    This book approaches coal gasification and related technologies from a process engineering point of view, with topics chosen to aid the process engineer who is interested in a complete, coal-to-products system. It provides a perspective for engineers and scientists who analyze and improve components of coal conversion processes. The first topic describes the nature and availability of coal. Next, the fundamentals of gasification are described, followed by a description of gasification technologies and gas cleaning processes. The conversion of syngas to electricity, fuels and chemicals is then discussed. Finally, process economics are covered. Emphasis is given to the selection of gasification technology based on the type of coal fed to the gasifier and desired end product: E.g., lower temperature gasifiers produce substantial quantities of methane, which is undesirable in an ammonia synthesis feed. This book also reviews gasification kinetics which is informed by recent papers and process design studies by the US Department of Energy and other groups. Approaches coal gasification and related technologies from a process engineering point of view, providing a perspective for engineers and scientists who analyze and improve components of coal conversion processes - Describes the fundamentals of gasification, gasification technologies, and gas cleaning processes - Emphasizes the importance of the coal types fed to the gasifier and desired end products - Covers gasification kinetics.

  6. The shell coal gasification process

    Koenders, L.O.M.; Zuideveld, P.O. [Shell Internationale Petroleum Maatschappij B.V., The Hague (Netherlands)


    Future Integrated Coal Gasification Combined Cycle (ICGCC) power plants will have superior environmental performance and efficiency. The Shell Coal Gasification Process (SCGP) is a clean coal technology, which can convert a wide range of coals into clean syngas for high efficiency electricity generation in an ICGCC plant. SCGP flexibility has been demonstrated for high-rank bituminous coals to low rank lignites and petroleum coke, and the process is well suited for combined cycle power generation, resulting in efficiencies of 42 to 46% (LHV), depending on choice of coal and gas turbine efficiency. In the Netherlands, a 250 MWe coal gasification combined cycle plant based on Shell technology has been built by Demkolec, a development partnership of the Dutch Electricity Generating Board (N.V. Sep). The construction of the unit was completed end 1993 and is now followed by start-up and a 3 year demonstration period, after that the plant will be part of the Dutch electricity generating system.

  7. Coal gasification in Europe

    This paper first analyzes European energy consumption and supply dynamics within the framework of the European Communities energy and environmental policies calling for the increased use of natural gas, reduced energy consumption, promotion of innovative renewable energy technologies, and the reduction of carbon dioxide emissions. This analysis evidences that, while, at present, the increased use of natural gas is an economically and environmentally advantageous policy, as well as, being strategically sound (in view of Middle East political instability), fuel interchangeability, in particular, the option to use coal, is vital to ensure stability of the currently favourable natural gas prices and offer a locally available energy alternative to foreign supplied sources. Citing the advantages to industry offered by the use of flexible, efficient and clean gaseous fuels, with interchangeability, the paper then illustrates the cost and environmental benefits to be had through the use of high efficiency, low polluting integrated gasification combined-cycle power plants equipped to run on a variety of fuels. In the assessment of technological innovations in this sector, a review is made of some of the commercially most promising gasification processes, e.g., the British Gas-Lurgi (BGL) slagging gasifier, the high-temperature Winkler (HTW) Rheinbraun, and the Krupp Koppers (PRENFLO) moving bed gasifier processes

  8. Coal gasification: A multiple talent

    Schreurs, H.


    Coal Gasification is on a pressurized route to commercial application. Ground breaking was performed by the Cool Water, Tennessee Eastman and UBE plants. Now several technical and commercial demonstrations are underway not only to show the readiness of the technology for commercial application. Another goal is further developed to reduce costs and to rise efficiency. The main feature of coal gasification is that it transforms a difficult-to-handle fuel into an easy-to-handle one. Through a high efficient gas-turbine cycle-power production becomes easy, efficient and clean. Between gasification and power production several more or less difficult hurdles have to be taken. In the past several studies and R and D work have been performed by Novem as by others to get insight in these steps. Goals were to develop easier, more efficient and less costly performance of the total combination for power production. This paper will give an overview of these studies and developments to be expected. Subjects will be fuel diversification, gas treating and the combination of Integrated Coal Gasification Combined Cycle with several cycle and production of chemical products. As a conclusion a guide will be given on the way to a clean, efficient and commercial acceptable application of coal gasification. A relation to other emerging technologies for power production with coal will be presented.

  9. The role of high-Btu coal gasification technology

    German, M. I.

    An analysis is given of the role and economic potential of Lurgi-technology gasification of coal to the year 2000, in relation to other gas-supply options, the further development of gasifier designs, and probable environmental impact. It is predicted that coal gasification may reach 10% of total gas supplies by the year 2000, with Eastern U.S. coal use reaching commercially significant use in the 1990's. It is concluded that coal gasification is the cleanest way of using coal, with minimal physical, chemical, biological and socioeconomic impacts.

  10. The Shell coal gasification process

    This paper reports that Future Integrated Gasification Combined Cycle (IGCC) power plants will have superior environmental performance and unmatched efficiency. Efficiency depends on many factors including the type of coal, the gasification process, the gas turbine, the steam cycle. NOx reduction measures and the degree and manner of integration. The Shell Coal Gasification Process (SCGP) is a clean coal technology, which can convert a wide range of coals into clean syngas for high efficiency electricity generation in an IGCC plant. SCGP flexibility has been demonstrated for feeds ranging from bituminous coals to lignites and petroleum coke, and the process is ideally suited for combined cycle power generation, resulting in efficiencies of 42 to 46% (LHV). The excellent environmental capabilities of IGCC systems are based on well established treating processes for removing sulphur and nitrogen species form the syngas. IGCC processes produce modest volumes of environmentally acceptable effluents. Gas turbine burner developments imply lower NOx emissions. In the Netherlands, a 250 MWe coal gasification combined cycle plant based on Shell technology is being built by Demkolec, a development partnership of the Dutch Electricity Generating Board (N.V. Sep). The plant is scheduled to start up in 1993

  11. Advanced treatment of biologically pretreated coal gasification wastewater by a novel integration of catalytic ultrasound oxidation and membrane bioreactor.

    Jia, Shengyong; Han, Hongjun; Zhuang, Haifeng; Xu, Peng; Hou, Baolin


    Laboratorial scale experiments were conducted to investigate a novel system integrating catalytic ultrasound oxidation (CUO) with membrane bioreactor (CUO-MBR) on advanced treatment of biologically pretreated coal gasification wastewater. Results indicated that CUO with catalyst of FeOx/SBAC (sewage sludge based activated carbon (SBAC) which loaded Fe oxides) represented high efficiencies in eliminating TOC as well as improving the biodegradability. The integrated CUO-MBR system with low energy intensity and high frequency was more effective in eliminating COD, BOD5, TOC and reducing transmembrane pressure than either conventional MBR or ultrasound oxidation integrated MBR. The enhanced hydroxyl radical oxidation, facilitation of substrate diffusion and improvement of cell enzyme secretion were the mechanisms for CUO-MBR performance. Therefore, the integrated CUO-MBR was the promising technology for advanced treatment in engineering applications. PMID:25936898

  12. Historical development of underground coal gasification

    Olness, D.; Gregg, D.W.


    The development of underground coal gasification is traced through a discussion of the significant, early experiments with in situ gasification. Emphasized are the features of each experiment that were important in helping to alter and refine the process to its present state. Experimental details, coal characteristics, and gasification data are supplied for many of the experiments. 69 refs.

  13. Environmental benefits of underground coal gasification.

    Liu, Shu-qin; Liu, Jun-hua; Yu, Li


    Environmental benefits of underground coal gasification are evaluated. The results showed that through underground coal gasification, gangue discharge is eliminated, sulfur emission is reduced, and the amount of ash, mercury, and tar discharge are decreased. Moreover, effect of underground gasification on underground water is analyzed and CO2 disposal method is put forward. PMID:12046301

  14. Development of Biological Coal Gasification (MicGAS Process). Topical report, July 1991--February 1993

    Srivastava, K.C.


    Laboratory and bench scale reactor research carried out during the report period confirms the feasibility of biomethanation of Texas lignite (TxL) and some other low-rank coals to methane by specifically developed unique anaerobic microbial consortia. The data obtained demonstrates specificity of a particular microbial consortium to a given lignite. Development of a suitable microbial consortium is the key to the success of the process. The Mic-1 consortium was developed to tolerate higher coal loadings of 1 and 5% TxL in comparison to initial loadings of 0.01% and 0.1% TxL. Moreover, the reaction period was reduced from 60 days to 14 to 21 days. The cost of the culture medium for bioconversion was reduced by studying the effect of different growth factors on the biomethanation capability of Mic-1 consortium. Four different bench scale bioreactor configurations, namely Rotating Biological Contactor (RBC), Upflow Fluidized Bed Reactor (UFBR), Trickle Bed Reactor (TBR), and Continuously Stirred Tank Reactor (CSTR) were evaluated for scale up studies. Preliminary results indicated highest biomethanation of TxL by the Mic-1 consortium in the CSTR, and lowest in the trickle bed reactor. However, highest methane production and process efficiency were obtained in the RBC.

  15. Investigating and analyzing parameters of coal gasification

    Postrzednik, S.


    Investigations into coal gasification carried out by the Institute for Heat Technology of the Silesian Technical University in Gliwice within the MR-I-10 research program ('Optimization of thermodynamics and flow problems') are evaluated. The Institute is developing a mathematical model of coal gasification on a commercial scale. Laboratory investigations into reaction kinetics of coal gasification are aimed at determining relations used by this model. Test stand used for dry coal gasification, gasification procedure and calculation methods are discussed. The test stand consists of a heating system, an analytical balance, temperature control system, a system recording temperature fluctuations and a flow rate control system. The results of investigations are shown in the form of curves which describe isothermal coal gasification. 6 references.

  16. Gasification of coal to produce hydrogen

    The following are dealt with: a) The physico-chemical basis, the process and the potential applications of water vapour gasification, b) the present state of the gasification industrially used in West Germany at present (Lurgi, Winkler, Koppers-Totzek processes), c) the state and tasks, technical information, operators and projects of the experimental plant for further development of gasification processes commissioned in the 1970's in West Germany d) gasification of coal using heat from nuclear reactors, and e) the prospects of hydrogen supply by gasification of coal. (GG)

  17. Influence of phenol on ammonia removal in an intermittent aeration bioreactor treating biologically pretreated coal gasification wastewater.

    Xu, Chunyan; Han, Hongjun; Jia, Shengyong; Zhao, Qian


    A laboratory-scale intermittent aeration bioreactor was investigated to treat biologically pretreated coal gasification wastewater that was mainly composed of NH3-N and phenol. The results showed that increasing phenol loading had an adverse effect on NH3-N removal; the concentration in effluent at phenol loading of 40mgphenol/(L·day) was 7.3mg/L, 36.3% of that at 200mg phenol/(L·day). The enzyme ammonia monooxygenase showed more sensitivity than hydroxylamine oxidoreductase to the inhibitory effect of phenol, with 32.2% and 10.5% activity inhibition, respectively at 200mg phenol/(L·day). Owing to intermittent aeration conditions, nitritation-type nitrification and simultaneous nitrification and denitrification (SND) were observed, giving a maximum SND efficiency of 30.5%. Additionally, ammonia oxidizing bacteria (AOB) and denitrifying bacteria were the main group identified by fluorescent in situ hybridization. However, their relative abundance represented opposite variations as phenol loading increased, ranging from 30.1% to 17.5% and 7.6% to 18.2% for AOB and denitrifying bacteria, respectively. PMID:27155414

  18. Development of biological coal gasification (MicGAS Process). Eighth quarterly report


    This report describes progress on three fronts of the project. First in studies to elucidate optimal growing conditions for the consortia of coal degraders employed indicates that best growth occurs with 0. 2% w/v Shefton T. Secondly in comparing the biodegradative properties of the coal degraders, isolates identified as Mic-1 and Mic-4 were the best performers. And lastly bioreactors studies in batch mode are related.

  19. Coal gasification for electric power generation.

    Spencer, D F; Gluckman, M J; Alpert, S B


    The electric utility industry is being severely affected by rapidly escalating gas and oil prices, restrictive environmental and licensing regulations, and an extremely tight money market. Integrated coal gasification combined cycle (IGCC) power plants have the potential to be economically competitive with present commercial coal-fired power plants while satisfying stringent emission control requirements. The current status of gasification technology is discussed and the critical importance of the 100-megawatt Cool Water IGCC demonstration program is emphasized. PMID:17788466

  20. A novel integration of three-dimensional electro-Fenton and biological activated carbon and its application in the advanced treatment of biologically pretreated Lurgi coal gasification wastewater.

    Hou, Baolin; Han, Hongjun; Zhuang, Haifeng; Xu, Peng; Jia, Shengyong; Li, Kun


    A novel integrated process with three-dimensional electro-Fenton (3D EF) and biological activated carbon (BAC) was employed in advanced treatment of biologically pretreated Lurgi coal gasification wastewater. SAC-Fe (sludge deserved activated carbon from sewage and iron sludge) and SAC (sludge deserved activated carbon) were used in 3D EF as catalytic particle electrodes (CPEs) and in BAC as carriers respectively. Results indicated that 3D EF with SAC-Fe as CPEs represented excellent pollutants and COLOR removals as well as biodegradability improvement. The efficiency enhancement attributed to generating more H2O2 and OH. The integrated process exhibited efficient performance of COD, BOD5, total phenols, TOC, TN and COLOR removals at a much shorter retention time, with the corresponding concentrations in effluent of 31.18, 6.69, 4.29, 17.82, 13.88mg/L and <20 times, allowing discharge criteria to be met. The integrated system was efficient, cost-effective and ecological sustainable and could be a promising technology for engineering applications. PMID:26227570

  1. Production of Hydrogen from Underground Coal Gasification

    Upadhye, Ravindra S.


    A system of obtaining hydrogen from a coal seam by providing a production well that extends into the coal seam; positioning a conduit in the production well leaving an annulus between the conduit and the coal gasification production well, the conduit having a wall; closing the annulus at the lower end to seal it from the coal gasification cavity and the syngas; providing at least a portion of the wall with a bifunctional membrane that serves the dual purpose of providing a catalyzing reaction and selectively allowing hydrogen to pass through the wall and into the annulus; and producing the hydrogen through the annulus.

  2. Coal gasification using solar energy

    Mathur, V. K.; Breault, R. W.; Lakshmanan, S.


    An economic evaluation of conventional and solar thermal coal gasification processes is presented, together with laboratory bench scale tests of a solar carbonization unit. The solar design consists of a heliostat field, a central tower receiver, a gasifier, and a recirculation loop. The synthetic gas is produced in the gasifier, with part of the gas upgraded to CH4 and another redirected through the receiver with steam to form CO and H2. Carbonaceous fuels are burned whenever sunlight is not available. Comparisons are made for costs of Lurgi, Bi-gas, Hygas, CO2 Acceptor, and Peat Gas processes and hybrid units for each. Solar thermal systems are projected to become economical with 350 MWt output and production of 1,420,000 cu m of gas per day. The laboratory bench scale unit was tested with Montana rosebud coal to derive a heat balance assessment and analyse the product gas. Successful heat transfer through a carrier gas was demonstrated, with most of the energy being stored in the product gas.


    The close of 1999 marked the completion of the Demonstration Period of the Wabash River Coal Gasification Repowering Project. This Final Report summarizes the engineering and construction phases and details the learning experiences from the first four years of commercial operation that made up the Demonstration Period under Department of Energy (DOE) Cooperative Agreement DE-FC21-92MC29310. This 262 MWe project is a joint venture of Global Energy Inc. (Global acquired Destec Energy's gasification assets from Dynegy in 1999) and PSI Energy, a part of Cinergy Corp. The Joint Venture was formed to participate in the Department of Energy's Clean Coal Technology (CCT) program and to demonstrate coal gasification repowering of an existing generating unit impacted by the Clean Air Act Amendments. The participants jointly developed, separately designed, constructed, own, and are now operating an integrated coal gasification combined-cycle power plant, using Global Energy's E-Gas(trademark) technology (E-Gas(trademark) is the name given to the former Destec technology developed by Dow, Destec, and Dynegy). The E-Gas(trademark) process is integrated with a new General Electric 7FA combustion turbine generator and a heat recovery steam generator in the repowering of a 1950's-vintage Westinghouse steam turbine generator using some pre-existing coal handling facilities, interconnections, and other auxiliaries. The gasification facility utilizes local high sulfur coals (up to 5.9% sulfur) and produces synthetic gas (syngas), sulfur and slag by-products. The Project has the distinction of being the largest single train coal gasification combined-cycle plant in the Western Hemisphere and is the cleanest coal-fired plant of any type in the world. The Project was the first of the CCT integrated gasification combined-cycle (IGCC) projects to achieve commercial operation




    The close of 1999 marked the completion of the Demonstration Period of the Wabash River Coal Gasification Repowering Project. This Final Report summarizes the engineering and construction phases and details the learning experiences from the first four years of commercial operation that made up the Demonstration Period under Department of Energy (DOE) Cooperative Agreement DE-FC21-92MC29310. This 262 MWe project is a joint venture of Global Energy Inc. (Global acquired Destec Energy's gasification assets from Dynegy in 1999) and PSI Energy, a part of Cinergy Corp. The Joint Venture was formed to participate in the Department of Energy's Clean Coal Technology (CCT) program and to demonstrate coal gasification repowering of an existing generating unit impacted by the Clean Air Act Amendments. The participants jointly developed, separately designed, constructed, own, and are now operating an integrated coal gasification combined-cycle power plant, using Global Energy's E-Gas{trademark} technology (E-Gas{trademark} is the name given to the former Destec technology developed by Dow, Destec, and Dynegy). The E-Gas{trademark} process is integrated with a new General Electric 7FA combustion turbine generator and a heat recovery steam generator in the repowering of a 1950's-vintage Westinghouse steam turbine generator using some pre-existing coal handling facilities, interconnections, and other auxiliaries. The gasification facility utilizes local high sulfur coals (up to 5.9% sulfur) and produces synthetic gas (syngas), sulfur and slag by-products. The Project has the distinction of being the largest single train coal gasification combined-cycle plant in the Western Hemisphere and is the cleanest coal-fired plant of any type in the world. The Project was the first of the CCT integrated gasification combined-cycle (IGCC) projects to achieve commercial operation.

  5. Groundwater Pollution from Underground Coal Gasification


    In situ coal gasification poses a potential environmental risk to groundwater pollution although it depends mainly on local hydrogeological conditions.In our investigation, the possible processes of groundwater pollution originating from underground coal gasification (UCG) were analyzed.Typical pollutants were identified and pollution control measures are proposed.Groundwater pollution is caused by the diffusion and penetration of contaminants generated by underground gasification processes towards surrounding strata and the possible leaching of underground residue by natural groundwater flow after gasification.Typical organic pollutants include phenols, benzene, minor components such as PAHs and heterocyclics.Inorganic pollutants involve cations and anions.The natural groundwater flow after gasification through the seam is attributable to the migration of contaminants, which can be predicted by mathematical modeling.The extent and concentration of the groundwater pollution plume depend primarily on groundwater flow velocity, the degree of dispersion and the adsorption and reactions of the various contaminants.The adsorption function of coal and surrounding strata make a big contribution to the decrease of the contaminants over time and with the distance from the burn cavity.Possible pollution control measures regarding UCG include identifying a permanently, unsuitable zone, setting a hydraulic barrier and pumping contaminated water out for surface disposal.Mitigation measures during gasification processes and groundwater remediation after gasification are also proposed.

  6. Coal gasification: technology for the power industry

    Andrus, H.E.; Vroom, H. (ABB Combustion Engineering (United States))


    In the USA, coal is currently used to produce about 55 per cent of the nation's electricity. However, now that the country's Clean Air Act (CAA) is firmly in place, coalburning electric utilities must comply with environmental regulations that will become increasingly stringent over the next 10 years. As a result of the US Clean Air Act, ''clean coal technologies'' like coal gasification are now being proposed as viable alternatives to traditional coal-burning power plants. With forecasters predicting a need for new baseload capacity by the end of the century and new technologies that can better meet CAA regulations, coal gasification is expected to become one of the country's major coal-burning technology options. (5 figures, 2 tables) (Author)

  7. Coal gasification and the power production market

    The US electric power production market is experiencing significant changes sparking interest in the current and future alternatives for power production. Coal gasification technology is being marketed to satisfy the needs of the volatile power production industry. Coal gasification is a promising power production process in which solid coal is burned to produce a synthesis gas (syn gas). The syn gas may be used to fuel combustion integrated into a facility producing electric power. Advantages of this technology include efficient power production, low flue gas emissions, flexible fuel utilization, broad capability for facility integration, useful process byproducts, and decreased waste disposal. The primary disadvantages are relatively high capital costs and lack of proven long-term operating experience. Developers of coal gasification intend to improve on these disadvantages and lop a strong position in the power generation market. This paper is a marketing analysis of the partial oxidation coal gasification processes emerging in the US in response to the market factors of the power production industry. A brief history of these processes is presented, including the results of recent projects exploring the feasibility of integrated gasification combined cycle (IGCC) as a power production alternative. The current power generation market factors are discussed, and the status of current projects is presented including projected performance

  8. Heterogeneous catalytic ozonation of biologically pretreated Lurgi coal gasification wastewater using sewage sludge based activated carbon supported manganese and ferric oxides as catalysts.

    Zhuang, Haifeng; Han, Hongjun; Hou, Baolin; Jia, Shengyong; Zhao, Qian


    Sewage sludge of biological wastewater treatment plant was converted into sewage sludge based activated carbon (SBAC) with ZnCl₂ as activation agent, which supported manganese and ferric oxides as catalysts (including SBAC) to improve the performance of ozonation of real biologically pretreated Lurgi coal gasification wastewater. The results indicated catalytic ozonation with the prepared catalysts significantly enhanced performance of pollutants removal and the treated wastewater was more biodegradable and less toxic than that in ozonation alone. On the basis of positive effect of higher pH and significant inhibition of radical scavengers in catalytic ozonation, it was deduced that the enhancement of catalytic activity was responsible for generating hydroxyl radicals and the possible reaction pathway was proposed. Moreover, the prepared catalysts showed superior stability and most of toxic and refractory compounds were eliminated at successive catalytic ozonation runs. Thus, the process with economical, efficient and sustainable advantages was beneficial to engineering application. PMID:24907577

  9. Solar coal gasification - Plant design and economics

    Aiman, W. R.; Thorsness, C. B.; Gregg, D. W.

    A plant design and economic analysis is presented for solar coal gasification (SCG). Coal pyrolysis and char gasification to form the gasified product are reviewed, noting that the endothermic gasification reactions occur only at temperatures exceeding 1000 K, an energy input of 101-136 kJ/mol of char reformed. Use of solar heat offers the possibility of replacing fuels needed to perform the gasification and the oxygen necessary in order to produce a nitrogen-free product. Reactions, energetics, and byproducts from the gasification of subbituminous coal are modeled for a process analysis code used for the SCG plant. Gas generation is designed to occur in a unit exposed to the solar flux focus from a heliostat field. The SCG gas would have an H2 content of 88%, compared to the 55% offered by the Lurgi process. Initial capital costs for the SCG plant are projected to be 4 times those with the Lurgi process, with equality being achieved when coal costs $4/gJ.

  10. Underground coal gasification. Gasificacion subterranea del carbon

    Del Amor, G.; Obis, A. (ITGE, Madrid (Spain))


    In spite of the low price of both oil and gas, underground coal gasification is still an attractive option because of the possibility for exploiting coal which it would be uneconomic to mine by conventional methods. New technology has recently made gasification into a reality and methods have been developed to gasify both deep and superficial inclined seams. Recent tests in nearly level seams in the USA have been successful so that the process has become competitive in spite of current oil prices. 3 figs.

  11. Clean Coal and Gasification Technology: How it Works?

    Marina Sidorová; Gabriel Wittenberger


    Gasification of coal is the oldest method for the production of hydrogen. Coal gasification is a process that converts coal from a solid to a gaseous state. The gas that is created is very similar to natural gas and can be used to produce chemicals, fertilizers, and/or the electric power [1]. Cleanest of all coal-based electric power technologies, gasification has significantly lower levels of air emissions (including volatile mercury), solid wastes, and wastewater.Due to its high efficiencie...

  12. Coal gasification. Quo vadis?; Kohlevergasung. Quo Vadis?

    Graebner, Martin; Meyer, Bernd [Technische Univ. Bergakademie Freiberg (Germany). Dept. of Energy Process Engineering and Chemical Engineering


    To summarize, it can be stated for coal gasification that in the last decade, an increase of synthesis gas capacity of 17.7 GW was observed, mainly concentrated in the Chinese region (15.3 GW). All these plants produce chemicals, primarily ammonia and methanol. Most of the announced North American and European IGCC projects (partly including CO{sub 2} capture) are either on hold or canceled. Hence, the development shows that mono-power generation applying CCS is not feasible under the current boundary conditions. If one poses the question ''Coal gasification - Quo vadis?'', it would be instructive to develop new strategies keeping in mind boundary conditions like oil depletion, climate protection, coal properties and grid instabilities. Since lots of chemical raw materials contain carbon, a carbon source for the post-oil era has to be identified. As only gasification processes are able to condition coal for chemical utilization, they indicate the direction for further development. In this context it is advisable to combine the production os chemicals and power. Modern polygeneration plants or ''energy factories'' would allow the highest creation of value at minimized CO{sub 2} emissions and flexible load deploying processes tailored to coal quality. The experiences of the recently constructed plants will enrich research and development so that concept design could successfully materialize as technical installations. (orig.)

  13. Technical and economic aspects of brown coal gasification and liquefaction

    A number of gasification and liquefaction processes for Rhenish brown coal are investigated along with the technical and economic aspects of coal beneficiation. The status of coal beneficiation and the major R + D activities are reviewed. (orig.)

  14. High-Btu coal gasification processes

    Blazek, C.F.; Baker, N.R.; Tison, R.R.


    This evaluation provides estimates of performance and cost data for advanced technology, high-Btu, coal gasification facilities. The six processes discussed reflect the current state-of-the-art development. Because no large commercial gasification plants have yet been built in the United States, the information presented here is based only on pilot-plant experience. Performance characteristics that were investigated include unit efficiencies, product output, and pollution aspects. Total installed plant costs and operating costs are tabulated for the various processes. The information supplied here will assist in selecting energy conversion units for an Integrated Community Energy System (ICES).

  15. The feasibility of using combined TiO2 photocatalysis oxidation and MBBR process for advanced treatment of biologically pretreated coal gasification wastewater.

    Xu, Peng; Han, Hongjun; Hou, Baolin; Zhuang, Haifeng; Jia, Shengyong; Wang, Dexin; Li, Kun; Zhao, Qian


    The study examined the feasibility of using combined heterogeneous photocatalysis oxidation (HPO) and moving bed biofilm reactor (MBBR) process for advanced treatment of biologically pretreated coal gasification wastewater (CGW). The results indicated that the TOC removal efficiency was significantly improved in HPO. Gas chromatography-mass spectrometry (GC-MS) analysis indicated that the HPO could be employed to eliminate bio-refractory and toxic compounds. Meanwhile, the BOD5/COD of the raw wastewater was increased from 0.08 to 0.49. Furthermore, in the integration of TiO2 photocatalysis oxidation and MBBR process, the effluent of COD, BOD5, TOC, NH4(+)-N and TN were 22.1 mg/L, 1.1 mg/L, 11.8 mg/L, 4.1mg/L and 13.7 mg/L, respectively, which all met class-I criteria of the Integrated Wastewater Discharge Standard (GB18918-2002, China). The total operating cost was 2.8CNY/t. Therefore, there is great potential for the combined system in engineering applications as a final treatment for biologically pretreated CGW. PMID:25934578

  16. Fuel economy: thermochemical regeneration and new method of coal gasification

    Nosach, V.H.


    Heat regeneration and coal gasification are two means of increasing the efficiency of utilizing fossil fuel resources. Two methods of heat regeneration are discussed: air regeneration and a new method, thermochemical regeneration. Use of thermochemical regeneration in heat-utilizing aggregates has increased fuel efficiency by 15-20%, and the combined use of both heat regeneration methods is also highly effective. The increased use of coal is generally associated with the greater air pollution. The most effective method of controlling harmful atmospheric emissions by coal-fueled power plants is a two-stage combustion system with preliminary coal gasification to remove sulfur and ash and combustion of the pure gasification products. But the introduction of coal gasification has increased the need for designing new gas generators. The advantages of using coal gasification at electric power plants include increasing the reliability of steam generators, decreasing expenditures for transporting fuel, and more complete utilization of coal. Coal gasification also broadens the use of low-quality coal. Gasification of Siberian coal with the production of synthetic natural gas also lessens the problem of transporting energy resources from Siberia to central regions of the USSR. A continuous method has been developed for producing synthetic gas by steam gasification of coal without use of oxygen.

  17. Carbon Dioxide Sorption Capacities of Coal Gasification Residues

    Thomas Kempka; T. Fernandez-Steeger; Li, D.; Schulten, M.; Schlüter, R; B. M. Krooss


    Underground coal gasification is currently being considered as an economically and environmentally sustainable option for development and utilization of coal deposits not mineable by conventional methods. This emerging technology in combination with carbon capture and sorptive CO2 storage on the residual coke as well as free-gas CO2 storage in the cavities generated in the coal seams after gasification could provide a relevant contribution to the development of Clean Coal Technologies. Three ...

  18. Robustness studies on coal gasification process variables

    RLJ Coetzer


    Full Text Available Optimisation of the Sasol-Lurgi gasification process was carried out by utilising the method of Factorial Experimental Design on the process variables of interest from a specifically equipped full-scale test gasifier. The process variables that govern gasification are not always fully controllable during normal operation. This paper discusses the application of statistical robustness studies as a method for determining the most efficient combination of process variables that might be hard-to-control during normal operation. Response surface models were developed in the process variables for each of the performance variables. It will be shown how statistical robustness studies provided the optimal conditions for sustainable gasifier operability and throughput. In particular, the optimum operability region is significantly expanded towards higher oxygen loads by changing and controlling the particle size distribution of the coal.

  19. Wabash River coal gasification repowering project: Public design report



    The Wabash River Coal Gasification Repowering Project (the Project), conceived in October of 1990 and selected by the US Department of Energy as a Clean Coal IV demonstration project in September 1991, is expected to begin commercial operations in August of 1995. The Participants, Destec Energy, Inc., (Destec) of Houston, Texas and PSI Energy, Inc., (PSI) of Plainfield, Indiana, formed the Wabash River Coal Gasification Repowering Project Joint Venture (the JV) to participate in the DOE`s Clean Coal Technology (CCT) program by demonstrating the coal gasification repowering of an existing 1950`s vintage generating unit affected by the Clean Air Act Amendments (CAAA). The Participants, acting through the JV, signed the Cooperative Agreement with the DOE in July 1992. The Participants jointly developed, and separately designed, constructed, own, and will operate an integrated coal gasification combined cycle (CGCC) power plant using Destec`s coal gasification technology to repower Unit {number_sign}1 at PSI`s Wabash River Generating Station located in Terre Haute, Indiana. PSI is responsible for the new power generation facilities and modification of the existing unit, while Destec is responsible for the coal gasification plant. The Project demonstrates integration of the pre-existing steam turbine generator, auxiliaries, and coal handling facilities with a new combustion turbine generator/heat recovery steam generator tandem and the coal gasification facilities.

  20. Gasification of various types of tertiary coals: A sustainability approach

    Highlights: ► Production energy by burning of coals including high rate of ash and sulfur is harmful to environment. ► Energy production via coal gasification instead of burning is proposed for sustainable approach. ► We calculate exergy and environmental destruction factor of gasification of some tertiary coals. ► Sustainability index, improvement potential of gasification are evaluated for exergy-based approach. - Abstract: The utilization of coal to produce a syngas via gasification processes is becoming a sustainability option because of the availability and the economic relevance of this fossil source in the present world energy scenario. Reserves of coal are abundant and more geographically spread over the world than crude oil and natural gas. This paper focuses on sustainability of the process of coal gasification; where the synthesis gas may subsequently be used for the production of electricity, fuels and chemicals. The coal gasifier unit is one of the least efficient step in the whole coal gasification process and sustainability analysis of the coal gasifier alone can substantially contribute to the efficiency improvement of this process. In order to evaluate sustainability of the coal gasification process energy efficiency, exergy based efficiency, exergy destruction factor, environmental destruction factor, sustainability index and improvement potential are proposed in this paper.


    The report gives results of a theoretical investigation of the disposition of five volatile trace elements (arsenic, boron, lead, selenium, and mercury) in SNG-producing coal gasification plants. Three coal gasification processes (dry-bottom Lurgi, Koppers-Totzek, and HYGAS) were...


    The report summarizes results of a test program to characterize fugitive emissions from the Kosovo coal gasification plant in Yugoslavia, a test program implemented by the EPA in response to a need for representative data on the potential environmental impacts of Lurgi coal gasif...

  3. Basic equations of channel model for underground coal gasification


    The underground coal gasification has advantages of zero rubbish, nonpollution, low cost and high safety. According to the characteristics of the gasification, the channel model of chemical fluid mechanics is used to set up the fluid equations and chemical equations by some reasonable suppositions in this paper, which lays a theoretical foundation on requirements of fluid movement rules in the process of underground coal gasification.

  4. Development of biological coal gasification (MicGAS process). Final report, May 1, 1990--May 31, 1995



    ARCTECH has developed a novel process (MicGAS) for direct, anaerobic biomethanation of coals. Biomethanation potential of coals of different ranks (Anthracite, bitumious, sub-bitumious, and lignites of different types), by various microbial consortia, was investigated. Studies on biogasification of Texas Lignite (TxL) were conducted with a proprietary microbial consortium, Mic-1, isolated from hind guts of soil eating termites (Zootermopsis and Nasutitermes sp.) and further improved at ARCTECH. Various microbial populations of the Mic-1 consortium carry out the multi-step MicGAS Process. First, the primary coal degraders, or hydrolytic microbes, degrade the coal to high molecular weight (MW) compounds. Then acedogens ferment the high MW compounds to low MW volatile fatty acids. The volatile fatty acids are converted to acetate by acetogens, and the methanogens complete the biomethanation by converting acetate and CO{sub 2} to methane.

  5. Investigation of polycyclic aromatic hydrocarbons from coal gasification

    ZHOU Hong-cang; JIN Bao-sheng; ZHONG Zhao-ping; HUANG Ya-ji; XIAO Rui; LI Da-ji


    The hazardous organic pollutants generated from coal gasification, such as polycyclic aromatic hydrocarbons(PAHs), are highly mutagenic and carcinogenic. More researchers have paid particular attention to them. Using air and steam as gasification medium, the experiments of three kinds of coals were carried out in a bench-scale atmospheric fluidized bed gasifier. The contents of the 16 PAHs specified by US EPA in raw coal, slag, bag house coke, cyclone coke and gas were measured by HPLC to study the contents of PAHs in raw coal and the effects of the inherent characters of coals on the formation and release of PAHs in coal gasification. The experimental results showed that the distributions of PAHs in the gasified products are similar to raw coals and the total-PAHs content in coal gasification is higher than in raw coal(except Coal C). The total-PAHs contents increase and then decrease with the rise of fixed carbon and sulfur of coal while there has an opposite variation when volatile matters content increase. The quantities of PAHs reduce with the increase of ash content or the drop of heating value during coal gasification.

  6. Nuclear process heat - application to coal gasification

    The high temperature gas cooled reactor has achieved peak coolant temperatures from 775 to 9500C, depending on the core design. These temperatures are sufficiently high to consider the HTR as a source of heat for several large industrial processes. In this article the application is to a coal gasification process which produces a mixture of carbon monoxide and hydrogen as the key product. The gasifier system itself is coupled to the HTR via a catalyzed bed coal gasifier operating at 7000C and producing methane. The feed to this gasifier is a mixture of carbon monoxide, hydrogen and steam with the stoichiometry chosen to effect an overall athermal reaction so that no heat is directly transferred into the gasifier. Its hydrogen supply is generated by steam reforming the methane produced using the direct HTR heat. This indirect system has advantages in terms of its final product, indirect heat transer and ultimately in the savings of approximately 40% of the coal which would otherwise have been assumed in an all-coal process producing the same final product. (orig.)


    The Gas Research Institute (GRI) estimates that by the year 2010, 40% or more of U.S. gas supply will be provided by supplements including substitute natural gas (SNG) from coal. These supplements must be cost competitive with other energy sources. The first generation technologies for coal gasification e.g. the Lurgi Pressure Gasification Process and the relatively newer technologies e.g. the KBW (Westinghouse) Ash Agglomerating Fluidized-Bed, U-Gas Ash Agglomerating Fluidized-Bed, British Gas Corporation/Lurgi Slagging Gasifier, Texaco Moving-Bed Gasifier, and Dow and Shell Gasification Processes, have several disadvantages. These disadvantages include high severities of gasification conditions, low methane production, high oxygen consumption, inability to handle caking coals, and unattractive economics. Another problem encountered in catalytic coal gasification is deactivation of hydroxide forms of alkali and alkaline earth metal catalysts by oxides of carbon (CO(sub x)). To seek solutions to these problems, a team consisting of Clark Atlanta University (CAU, a Historically Black College and University, HBCU), the University of Tennessee Space Institute (UTSI) and Georgia Institute of Technology (Georgia Tech) proposed to identify suitable low melting eutectic salt mixtures for improved coal gasification. The research objectives of this project were to: Identify appropriate eutectic salt mixture catalysts for coal gasification; Assess agglomeration tendency of catalyzed coal; Evaluate various catalyst impregnation techniques to improve initial catalyst dispersion; Determine catalyst dispersion at high carbon conversion levels; Evaluate effects of major process variables (such as temperature, system pressure, etc.) on coal gasification; Evaluate the recovery, regeneration and recycle of the spent catalysts; and Conduct an analysis and modeling of the gasification process to provide better understanding of the fundamental mechanisms and kinetics of the process

  8. Coal gasification. Quarterly report, July-September 1979



    The status of 18 coal gasification pilot plants or supporting projects supported by US DOE is reviewed under the following headings: company involved, location, contract number, funding, gasification process, history, process description, flowsheet and progress in the July-September 1979 quarter. (LTN)

  9. Hot gas desulphurisation with dolomite sorbent in coal gasification

    Álvarez Rodríguez, Ramón; Clemente Jul, María del Carmen


    Gasification technologies are among the most promising electrical power generation options both from an environmental and efficiency point of view, as they allow efficient, environmentally-friendly use of national coal, as well as other carbonaceous materials mixed with coal, including high sulphur by-products.During gasification, sulphur is converted mainly into H2S and secondly into COS, and control of these has been researched using several H2S adsorbents. The aim of this paper was advance...

  10. Steam gasification of coal using a pressurized circulating fluidized bed

    Subject of this investigation is the process engineering of a coal gasification using nuclear heat. A special aspect is the efficiency. To this purpose a new method for calculating the kinetics of hard coal steam gasification in a fluidized bed is presented. It is used for evaluations of gasification kinetics in a large-scale process on the basis of laboratory-scale experiments. The method is verified by experimental data from a large-scale gasifier. The investment costs and the operating costs of the designed process are estimated. (orig.)

  11. Wabash River coal gasification repowering project -- first year operation experience

    Troxclair, E.J. [Destec Energy, Inc., Houston, TX (United States); Stultz, J. [PSI Energy, Inc., West Terre Haute, IN (United States)


    The Wabash River Coal Gasification Repowering Project (WRCGRP), a joint venture between Destec Energy, Inc. and PSI Energy, Inc., began commercial operation in November of 1995. The Project, selected by the United States Department of Energy (DOE) under the Clean Coal Program (Round IV) represents the largest operating coal gasification combined cycle plant in the world. This Demonstration Project has allowed PSI Energy to repower a 1950`s vintage steam turbine and install a new syngas fired combustion turbine to provide 262 MW (net) of electricity in a clean, efficient manner in a commercial utility setting while utilizing locally mined high sulfur Indiana bituminous coal. In doing so, the Project is also demonstrating some novel technology while advancing the commercialization of integrated coal gasification combined cycle technology. This paper discusses the first year operation experience of the Wabash Project, focusing on the progress towards achievement of the demonstration objectives.

  12. Underground coal gasification and the ways of their admission

    Beáta Jágerová; Ján Pinka; Mariana Mihočová


    Underground Coal Gasification (UCG) is the conversion of coal in the seam into a combustible gas. UCG is conceptually very simple but controlling the reaction and producing a consistent gas quality under a variety of geological and coal conditions is difficult to achieve. The basic concept has two boreholes, one for the injection of oxidants and the other for the removal of the product gas.UCG requires boreholes to access the coal, and three methods have been developed to connect them, namely...

  13. Application and development status of coal gasification technology in China

    BU Xue-peng; XU Zhen-gang


    Introduced the application and development status of coal gasification technology in China. The most widely used coal gasification technology in China is the atmospheric fixed-bed gasifier, its total number is about 9 000. About 30 pressurized fixed-bed gasifiers are in operation, and more than 10 atmospheric fluidized-bed gasifiers were used. There are 13 Texaco entrained-flow bed gasifiers are under operation,10 Texaco and 11 Shell gasifiers that are being installed or imported. About 10 underground gasifiers are under running now. The present R&D of coal gasification technologies are to improve the operation and controlling level of fixed-bed gasification technology, and developing or demonstration of fluidized-bed and entrained-flow bed gasifiers.

  14. Underground coal gasification technology impact on coal reserves in Colombia

    John William Rosso Murillo


    Full Text Available In situ coal gasification technology (Underground Coal Gasification–UCG– is an alternative to the traditional exploitation, due to it allows to reach the today’s inaccessible coal reserves’ recovery, to conventional mining technologies. In this article I answer the question on how the today’s reserves available volume, can be increased, given the possibility to exploit further and better the same resources. Mining is an important wealth resource in Colombia as a contributor to the national GDP. According with the Energy Ministry (Ministerio de Minas y Energía [1] mining has been around 5% of total GDP in the last years. This is a significant fact due to the existence of a considerable volume of reserves not accounted for (proved reserves at year 2010 were 6.700 million of tons. Source: INGEOMINAS and UPME, and the coal future role’s prospect, in the world energy production.

  15. Solar coal gasification reactor with pyrolysis gas recycle

    Aiman, William R.; Gregg, David W.


    Coal (or other carbonaceous matter, such as biomass) is converted into a duct gas that is substantially free from hydrocarbons. The coal is fed into a solar reactor (10), and solar energy (20) is directed into the reactor onto coal char, creating a gasification front (16) and a pyrolysis front (12). A gasification zone (32) is produced well above the coal level within the reactor. A pyrolysis zone (34) is produced immediately above the coal level. Steam (18), injected into the reactor adjacent to the gasification zone (32), reacts with char to generate product gases. Solar energy supplies the energy for the endothermic steam-char reaction. The hot product gases (38) flow from the gasification zone (32) to the pyrolysis zone (34) to generate hot char. Gases (38) are withdrawn from the pyrolysis zone (34) and reinjected into the region of the reactor adjacent the gasification zone (32). This eliminates hydrocarbons in the gas by steam reformation on the hot char. The product gas (14) is withdrawn from a region of the reactor between the gasification zone (32) and the pyrolysis zone (34). The product gas will be free of tar and other hydrocarbons, and thus be suitable for use in many processes.

  16. A contrast study on different gasifying agents of underground coal gasification at Huating Coal Mine

    WANG Zuo-tang; HUANG Wen-gang; ZHANG Peng; XIN Lin


    To optimize the technological parameter of underground coal gasification (UCG), the experimental results of air gasification, air-steam gasification, oxygen-enrichment steam gasification, pure oxygen steam gasification and two-stage gasification were studied contrastively based on field trial at the Huating UCG project. The results indicate that the average low heat value of gas from air experiment is the lowest (4.1 MJ/Nm3) and the water gas from two-stage gasification experiment is the highest (10.72 MJ/Nm3). The gas productivity of air gasification is the highest and the pure oxygen steam gasification is the lowest. The gasification efficiency of air gasification, air-steam gasification, oxygen-enriched steam gasification, pure oxygen steam gasification and two-stage gasification is listed in ascending order, ranging from 69.88% to 84.81%. Described a contract study on results of a field test using steam and various levels of oxygen enrichment of 21%, 32%, 42% and 100%. The results show that, with the increasing of O2 content in gasifying agents, the gas caloricity rises, and the optimal O2 concentration range to increase the gas caloricity is 30%~40%. Meanwhile, the consumption of O2 and steam increase, and the air consumption and steam decomposition efficiency fall.

  17. An Alberta firm dives into deep coal gasification

    Petkau, R.


    A synfuel plant in Calgary is now planning to gasify coal deposits located more than 1000 meters underground, and at the same time pump up a synthetic gas made of methane and hydrogen that is less greenhouse gas (GHG) intensive than natural gas. The plant will be the first in a series of commercial projects that will use carbon capture and storage to prevent air emissions from in situ coal gasification processes. The demonstration project will showcase the gasification technology, which subjects coal to heat and pressure in order to cause a series of chemical reactions that convert the feedstock into syngas. A pair of wells is drilled into the coal seam. Oxygen and water is then injected to support a limited amount of combustion. The combined effect of the high temperatures, steam, and natural in situ pressure create the right conditions for the coal to undergo gasification. The process is less expensive than surface gasification. Slag and ash byproducts also remain underground. Water used in the process is recycled and re-used, and the process does not contaminate fresh water supplies. It was concluded that a significant portion of Alberta's 600 billion tonnes of deep coal reserves are amenable to the gasification process. 3 figs.

  18. Engineering study hard coal gasification with pressurized water reactor

    Work has been concentrated on the design of the power plant and the interface between reactor and gasification unit. First of all, the combination of a PWR with a Lurgi pressure gasification was investigated. This first phase of the study has been completed. To meet the Lurgi pressure gasification characteristics, the saturated PWR-steam is brought to the required higher stage of pressure by steam compressors and superheated by fossil fired steam boilers. To obtain the higher availability of process steam for the hard coal gasification coal fired quick start stand-by boilers are provided. To judge the economic prospectives, the costs for supply of process steam and electric energy have been determined. The results are showing that hard coal gasification with a PWR is more economic than autothermal processes and that it is expedient and promising to continue the work on combined gasification processes in order to improve the efficiency of the overall plant. By request of the public authorities the RAG/Ruhrgas work on advanced gasification processes to be coupled with a PWR has been stopped temporary. (orig.)

  19. Hydrogen manufacture by Lurgi gasification of Oklahoma coal


    Advantages and disadvantages of using the Lurgi gasification process to produce hydrogen from Oklahoma coal are listed. Special attention was given to the production of heat for the process; heat is generated by burning part of pretreated coal in the steam generator. Overall performance of the Lurgi process is summarized in tabular form.

  20. Entrained flow gasification of coal/bio-oil slurries

    Feng, Ping; Lin, Weigang; Jensen, Peter Arendt;


    steam/carbon ratio of 5, the syngas components are similar with that in equilibrium. A synergistic effect exists between coal and bio-oil in coal/bio-oil slurry gasification which might be caused by the catalysis effect of alkali metals and alkaline earth metals in bio-oil....

  1. Advanced Hydrogen Transport Membrane for Coal Gasification

    Schwartz, Joseph [Praxair, Inc., Tonawanda, NY (United States); Porter, Jason [Colorado School of Mines, Golden, CO (United States); Patki, Neil [Colorado School of Mines, Golden, CO (United States); Kelley, Madison [Colorado School of Mines, Golden, CO (United States); Stanislowski, Josh [Univ. of North Dakota, Grand Forks, ND (United States); Tolbert, Scott [Univ. of North Dakota, Grand Forks, ND (United States); Way, J. Douglas [Colorado School of Mines, Golden, CO (United States); Makuch, David [Praxair, Inc., Tonawanda, NY (United States)


    A pilot-scale hydrogen transport membrane (HTM) separator was built that incorporated 98 membranes that were each 24 inches long. This separator used an advanced design to minimize the impact of concentration polarization and separated over 1000 scfh of hydrogen from a hydrogen-nitrogen feed of 5000 scfh that contained 30% hydrogen. This mixture was chosen because it was representative of the hydrogen concentration expected in coal gasification. When tested with an operating gasifier, the hydrogen concentration was lower and contaminants in the syngas adversely impacted membrane performance. All 98 membranes survived the test, but flux was lower than expected. Improved ceramic substrates were produced that have small surface pores to enable membrane production and large pores in the bulk of the substrate to allow high flux. Pd-Au was chosen as the membrane alloy because of its resistance to sulfur contamination and good flux. Processes were developed to produce a large quantity of long membranes for use in the demonstration test.

  2. Underground coal gasification and the ways of their admission

    Underground Coal Gasification (UCG) is the conversion of coal in the seam into a combustible gas. UCG is conceptually very simple but controlling the reaction and producing a consistent gas quality under a variety of geological and coal conditions is difficult to achieve. The basic concept has two boreholes, one for the injection of oxidants and the other for the removal of the product gas. (authors)

  3. Ground subsidence resulting from underground gasification of coal. [36 refs

    Gregg, D W


    Ground subsidence has been found to be a very significant physical phenomenon that must be dealt with in the design and operation of an underground coal gasification process. This report deals with the types of subsidence that one might expect, and how they affect the process. A brief theory of bending subsidence is presented, and the experience the Soviets had while operating their commercial underground gasification stations is reviewed.

  4. Utilization of chemical looping strategy in coal gasification processes

    Liangshih Fan; Fanxing Li; Shwetha Ramkumar


    Three chemical looping gasification processes, i. e. Syngas Chemical Looping (SCL) process, Coal Direct Chemical Looping (CDCL) process, and Calcium Looping process (CLP), are being developed at the Ohio State University (OSU). These processes utilize simple reaction schemes to convert carbonaceous fuels into products such as hydrogen, electricity, and synthetic fuels through the transformation of a highly reactive, highly recyclable chemical intermediate. In this paper, these novel chemical looping gasification processes are described and their advantages and potential challenges for commercialization are discussed.

  5. Steam gasification of coal, project prototype plant nuclear process heat

    This report describes the tasks, which Bergbau-Forschung has carried out in the field of steam gasification of coal in cooperation with partners and contractors during the reference phase of the project. On the basis of the status achieved to date it can be stated, that the mode of operation of the gas-generator developed including the direct feeding of caking high volatile coal is technically feasible. Moreover through-put can be improved by 65% at minimum by using catalysts. On the whole industrial application of steam gasification - WKV - using nuclear process heat stays attractive compared with other gasification processes. Not only coal is conserved but also the costs of the gas manufactured are favourable. As confirmed by recent economic calculations these are 20 to 25% lower. (orig.)

  6. Coal gasification. Quarterly report, January--March 1977



    High-Btu natural gas has a heating value of 950 to 1,000 Btu per standard cubic foot, is composed essentially of methane, and contains virtually no sulfur, carbon monoxide, or free hydrogen. The conversion of coal to high-Btu gas requires a chemical and physical transformation of solid coal. However, because coal has widely differing chemical and physical properties, depending on where it is mined, it is difficult to process. Therefore, to develop the most suitable techniques for gasifying coal, ERDA, together with the American Gas Association is sponsoring the development of several advanced conversion processes. Although the basic coal-gasification chemical reactions are the same for each process, the processes under development have unique characteristics. A number of the processes for converting coal to high Btu and to low Btu gas have reached the pilot plant stage. The responsibility for designing, constructing and operating each of these pilot plants is defined and progress on each during the quarter is described briefly. The accumulation of data for a coal gasification manual and the development of mathematical models of coal gasification processes are reported briefly. (LTN)

  7. Flow Simulation and Optimization of Plasma Reactors for Coal Gasification

    冀春俊; 张英姿; 马腾才


    This paper reports a 3-d numerical simulation system to analyze the complicatedflow in plasma reactors for coal gasification, which involve complex chemical reaction, two-phaseflow and plasma effect. On the basis of analytic results, the distribution of the density, tempera-ture and components' concentration are obtained and a different plasma reactor configuration isproposed to optimize the flow parameters. The numerical simulation results show an improvedconversion ratio of the coal gasification. Different kinds of chemical reaction models are used tosimulate the complex flow inside the reactor. It can be concluded that the numerical simulationsystem can be very useful for the design and optimization of the plasma reactor.

  8. Fugitive emission testing at the Kosovo coal gasification plant

    Honerkamp, R.L.


    This paper presents results of the first fugitive emission testing at a commercial-scale coal gasification plant in Kosovo, Yugoslavia. Data obtained are compared to data from similar testing at refineries and chemical plants. The main conclusions are: a) correlations between screening values and leak rates are similar to the relationship found in petroleum refineries and organic chemical manufacturing plants; b) the log-normal distribution of leaks is similar to the distribution found in refineries and chemical plants; c) fugitive emission control strategies developed for refineries and chemical plants should also be applicable to sources in coal gasification plants.

  9. Robustness studies on coal gasification process variables

    RLJ Coetzer; MJ Keyser


    Optimisation of the Sasol-Lurgi gasification process was carried out by utilising the method of Factorial Experimental Design on the process variables of interest from a specifically equipped full-scale test gasifier. The process variables that govern gasification are not always fully controllable during normal operation. This paper discusses the application of statistical robustness studies as a method for determining the most efficient combination of process variables that might be hard-to-...

  10. Co-gasification of oil sand coke with coal

    Vejahati, Farshid; Gupta, Rajender [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering


    Gasification of oil sand delayed coke with sub-bituminous and lignite coals was performed in an atmospheric entrained flow gasifier using steam and oxygen as gasifying agents. The underlying objective of this work was to assess the effects of the operating variables (i.e. temperature, oxygen and steam concentrations) and coal/coke blending ratio on gasification performance in a high-temperature in order to find the possible synergies in co-gasification of the fuels. Experiments were conducted at 1,400 C, using steam and oxygen to carbon weight ratios of (0.36-1.08) and (0.07-0.2), respectively in N{sub 2} carrier gas. The coke to coal weight ratios of 1/3, 1/2, and 2/3 were used for the blending tests. Particle size of 53-90 {mu}m with d{sub 50} = 75 {mu}m were used. In terms of char reactivity, blending did not show any significant positive effect. Slight deviations from linear additive line are in the order of experiment error. Gasification efficiency was also following a linear additive trend once more pointing out the lack of synergy in entrained flow gasification systems. The results however, showed that higher coke content clearly favored the H{sub 2} production.

  11. Exergoeconomical analysis of coal gasification combined cycle power plants

    This paper reports on combined cycle power plants with integrated coal gasification for a better utilization of primary energy sources which gained more and more importance. The established coal gasification technology offers various possibilities e.g. the TEXACO or the PRENFLO method. Recommendation for processes with these gasification methods will be evaluated energetically and exergetically. The pure thermodynamical analysis is at a considerable disadvantage in that the economical consequences of certain process improvement measures are not subjected to investigation. The connection of the exergetical with the economical evaluation will be realized in a way suggested as exergoeconomical analysis. This consideration of the reciprocal influencing of the exergy destruction and the capital depending costs is resulting in an optimization of the process and a minimization of the product costs

  12. Characteristics of Malaysian coals with their pyrolysis and gasification behaviour

    This study was conducted since comprehensive study on the gasification behaviour of Malaysian coals is still lacking. Coals were characterised using heating value determination, proximate analysis, ultimate analysis and ash analysis. Pyrolysis process was investigated using thermogravimetric analyser. While, atmospheric bubbling fluidized bed gasifier was used to investigate the gasification behaviour. Three Malaysian coals, Merit Pila, Mukah Balingian, Silantek; and Australian coal, Hunter Valley coals were used in this study. Thermal degradation of four coal samples were performed, which involved weight loss profile and derivative thermogravimetric (DTG) curves. The kinetic parameters, such as maximum reactivity value, Rmax, Activation Energy, Ea and Arrhenius constant, ln Ro for each coal were determined using Arrhenius Equation. Merit Pila coal shows the highest maximum reactivity among other Malaysian coals. Ea is the highest for Merit Pila coal (166.81kJmol-1) followed with Mukah Balingian (101.15 kJmol-1), Hunter Valley (96.45 kJmol-1) and Silantek (75.23 kJmol-1) coals. This finding indicates direct correlation of lower rank coal with higher Ea. Merit Pila coal was studied in detail using atmospheric bubbling fluidized bed gasifier. Different variables such as equivalence ratio (ER) and gasifying agents were used. The highest H2 proportion (38.3 mol.%) in the producer gas was reached at 715 degree Celsius and ER=0.277 where the maximization of LHVpg (5.56 MJ/Nm3) was also detected. ER and addition of steam had shown significant contributions to the producer gas compositions and LHVpg. (author)

  13. State-of-the-art and prospects with respect to power production by coal gasification (combined cycle coal gasification)

    The possibilities and limitations of clean coal technologies in power generation are discussed. Coal gasification is the best available coal technology for power generation for the future. In a demonstration project was confirmed that the emission values of sulphur and nitrogen oxides are low. The large scale use of clean coal technologies is still restrained by low market prices on the natural gas market. It is expected however that the advanced coal technologies option becomes competitive at the present prices for natural gas when the cost on investment is 1200 US dollar per k W at a yield of minimum 45 percent. In the short term, the combined gas cycle remains a reference for conventional power production. In the long term the evolution of energy supply and prices on the market will make the clean coal technologies an interesting option. (A.S.)

  14. Effects of coal drying on the pyrolysis and in-situ gasification characteristics of lignite coals

    Highlights: • Effect of coal drying on lignite pyrolysis was studied by TG-MS and a novel reactor. • Coal type, final temperature and heating method had key effects during pyrolysis. • We developed a new method to study morphological changes during char gasification. • It initially showed shrinking particle mode, and then changed to shrinking core mode. • Insignificant steam deactivation of char was verified by the active sites mechanism. - Abstract: Pyrolysis behaviors of two lignite coals with different drying conditions were determined by a thermogravimetric analyzer coupled with mass spectrometer (TG-MS) and a high-frequency furnace. An in-situ heating stage microscope was adopted to observe the morphological changes during char-CO2 gasification process. It is concluded that the effects of moisture contents in coals on the gaseous release process during coal pyrolysis mainly depend on coal type, final pyrolysis temperature and heating method. The in-situ heating stage experiments indicate that the shrinking particle mode is suitable to illustrate the gasification reaction mechanism in the initial and midterm reaction stages of all the lignite char samples. Although drying conditions have significant effects on coal pyrolysis process under rapid heating, these dewatering conditions result in little noticeable reactivity loss of the char during the subsequent char-CO2 gasification reaction. The measuring results of catalytic active sites can well explain the similar reactivity of lignite coals with different drying conditions

  15. Coal gasification systems engineering and analysis. Volume 1: Executive summary


    Feasibility analyses and systems engineering studies for a 20,000 tons per day medium Btu (MBG) coal gasification plant to be built by TVA in Northern Alabama were conducted. Major objectives were as follows: (1) provide design and cost data to support the selection of a gasifier technology and other major plant design parameters, (2) provide design and cost data to support alternate product evaluation, (3) prepare a technology development plan to address areas of high technical risk, and (4) develop schedules, PERT charts, and a work breakdown structure to aid in preliminary project planning. Volume one contains a summary of gasification system characterizations. Five gasification technologies were selected for evaluation: Koppers-Totzek, Texaco, Lurgi Dry Ash, Slagging Lurgi, and Babcock and Wilcox. A summary of the trade studies and cost sensitivity analysis is included.

  16. Wabash River Coal Gasification Repowering Project: A DOE Assessment

    National Energy Technology Laboratory


    The goal of the U.S. Department of Energy (DOE) Clean Coal Technology Program (CCT) is to furnish the energy marketplace with a number of advanced, more efficient, and environmentally responsible coal utilization technologies through demonstration projects. These projects seek to establish the commercial feasibility of the most promising advanced coal technologies that have developed beyond the proof-of-concept stage. This document serves as a DOE post-project assessment (PPA) of a project selected in CCT Round IV, the Wabash River Coal Gasification Repowering (WRCGR) Project, as described in a Report to Congress (U.S. Department of Energy 1992). Repowering consists of replacing an existing coal-fired boiler with one or more clean coal technologies to achieve significantly improved environmental performance. The desire to demonstrate utility repowering with a two-stage, pressurized, oxygen-blown, entrained-flow, integrated gasification combined-cycle (IGCC) system prompted Destec Energy, Inc., and PSI Energy, Inc., to form a joint venture and submit a proposal for this project. In July 1992, the Wabash River Coal Gasification Repowering Project Joint Venture (WRCGRPJV, the Participant) entered into a cooperative agreement with DOE to conduct this project. The project was sited at PSI Energy's Wabash River Generating Station, located in West Terre Haute, Indiana. The purpose of this CCT project was to demonstrate IGCC repowering using a Destec gasifier and to assess long-term reliability, availability, and maintainability of the system at a fully commercial scale. DOE provided 50 percent of the total project funding (for capital and operating costs during the demonstration period) of $438 million.

  17. Wabash River Coal Gasification Repowering Project: A DOE Assessment; FINAL

    The goal of the U.S. Department of Energy (DOE) Clean Coal Technology Program (CCT) is to furnish the energy marketplace with a number of advanced, more efficient, and environmentally responsible coal utilization technologies through demonstration projects. These projects seek to establish the commercial feasibility of the most promising advanced coal technologies that have developed beyond the proof-of-concept stage. This document serves as a DOE post-project assessment (PPA) of a project selected in CCT Round IV, the Wabash River Coal Gasification Repowering (WRCGR) Project, as described in a Report to Congress (U.S. Department of Energy 1992). Repowering consists of replacing an existing coal-fired boiler with one or more clean coal technologies to achieve significantly improved environmental performance. The desire to demonstrate utility repowering with a two-stage, pressurized, oxygen-blown, entrained-flow, integrated gasification combined-cycle (IGCC) system prompted Destec Energy, Inc., and PSI Energy, Inc., to form a joint venture and submit a proposal for this project. In July 1992, the Wabash River Coal Gasification Repowering Project Joint Venture (WRCGRPJV, the Participant) entered into a cooperative agreement with DOE to conduct this project. The project was sited at PSI Energy's Wabash River Generating Station, located in West Terre Haute, Indiana. The purpose of this CCT project was to demonstrate IGCC repowering using a Destec gasifier and to assess long-term reliability, availability, and maintainability of the system at a fully commercial scale. DOE provided 50 percent of the total project funding (for capital and operating costs during the demonstration period) of$438 million

  18. Simulation of coal char gasification using O2/CO2

    Haibin Li; Yu Yu; Minfang Han; Ze Lei


    The authors proposed an integrated gasification fuel cell zero-emission system. The coal char gasification is discussed using high temperature and concentration of CO2 produced by solid oxide fuel cells and oxy-fuel combustion. The gasification is simulated by Aspen plus based on Gibbs free energy minimization method. Gasification model of pulverized coal char is computed and analyzed. Effects of gas flow rate, pressure, preheating temperature, heat losses on syngas composition, reaction temperature, lower heating value and carbon conversion are studied. Results and parameters are determined as following. The optimum O2 flow rate is 20 kg/h. The reaction temperature decreases from 1645 to 1329 ?C when the CO2 flow rate increases from 0 to 5 kg/h, the CO2 flow rate should be operated reasonably; lower heating value reduces and reaction temperature increases as the pressure increases;compared to the CO2 preheating, O2 preheating has greater influence on reaction temperature and lower heating value.

  19. Comprehensive report to Congress, Clean Coal Technology program: Wabash River Coal Gasification Repowering Project

    Funding has been requested from DOE for the design, construction, and operation of a nominal 2544 ton-per-day (TPD) (265 MWe) two-stage, oxygen-blown, coal gasification combined-cycle (CGCC) repowering demonstration project, to be named the Wabash River Coal Gasification Repowering Project. The CGCC system will consist of an oxygen-blown, entrained-flow, Two-stage coal gasifier, which is capable of utilizing high sulfur bituminous coal; a gas conditioning system for removing sulfur compounds and particulates; systems or mechanical devices for improved coal feed; a combined-cycle power generation system wherein the conditioned fuel gas is combusted in a combustion turbine generator; a heat recovery steam generator; a gas cleanup system; and all necessary coal handling equipment

  20. Effect of powdered activated carbon technology on short-cut nitrogen removal for coal gasification wastewater.

    Zhao, Qian; Han, Hongjun; Xu, Chunyan; Zhuang, Haifeng; Fang, Fang; Zhang, Linghan


    A combined process consisting of a powdered activated carbon technology (PACT) and short-cut biological nitrogen removal reactor (SBNR) was developed to enhance the removal efficiency of the total nitrogen (TN) from the effluent of an upflow anaerobic sludge bed (UASB) reactor, which was used to treat coal gasification wastewater (CGW). The SBNR performance was improved with the increasing of COD and TP removal efficiency via PACT. The average removal efficiencies of COD and TP in PACT were respectively 85.80% and 90.30%. Meanwhile, the NH3-N to NO2-N conversion rate was achieved 86.89% in SBNR and the total nitrogen (TN) removal efficiency was 75.54%. In contrast, the AOB in SBNR was significantly inhibited without PACT or with poor performance of PACT in advance, which rendered the removal of TN. Furthermore, PAC was demonstrated to remove some refractory compounds, which therefore improved the biodegradability of the coal gasification wastewater. PMID:23735800

  1. Clean coal technology - Study on the pilot project experiment of underground coal gasification

    In this paper, the gasification conditions, the gasifier structure, the measuring system and the gasification rationale of a pilot project experiment of underground coal gasification (UCG) in the Liuzhuang Colliery, Tangshan, are illustrated. The technique of two-phase underground coal gasification is proposed. The detection of the moving speed and the length of the gasification working face is made using radon probing technology. An analysis of the experiment results indicates that the output of air gas is 3000 m3/h with a heating value of about 4.18 MJ/m3, while the output of water gas is 2000 m3/h with a heating value of over 11.00 MJ/m3, of which H2 content is above 40% with a maximum of 71.68%. The cyclical time of two-phase underground gasification is 16 h, with 8 h for each phase. This prolongs the time when the high-heating value gas is produced. The moving speed of the gasification working face in two alternative gasifiers is identified, i.e. 0.204 and 0.487 m/d, respectively. The success of the pilot project experiment of the underground gasification reveals the strides that have been made toward the commercialization of the UCG in China. It also further justifies the reasonability and feasibility of the new technology of long channel, big section, two-phase underground gasification. A conclusion is also drawn that the technology of the pilot project experiment can be popularized in old and discarded coal mines

  2. Underground Coal Gasification: Rates of Post Processing Gas Transport

    Soukup, Karel; Hejtmánek, Vladimír; Stanczyk, K.; Šolcová, Olga


    Roč. 68, č. 12 (2014), s. 1707-1715. ISSN 0366-6352 R&D Projects: GA MŠk 7C12017 Grant ostatní: RFCS(XE) RFCR-CT-2011-00002 Institutional support: RVO:67985858 Keywords : underground coal gasification * gas transport * textural properties Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.468, year: 2014

  3. Proceedings of second annual underground coal gasification symposium

    Shuck, L Z [ed.


    The Second Annual Underground Coal Gasification Symposium was sponsored by the Morgantown Energy Research Center of the US Energy Research and Development Administration and held at Morgantown, WV, August 10-12, 1976. Fifty papers of the proceedings have been entered individually into EDB and ERA. While the majority of the contribution involved ERDA's own work in this area, there were several papers from universities, state organizations, (industrial, engineering or utility companies) and a few from foreign countries. (LTN)

  4. The influence of particle size on the steam gasification kinetics of coal / Gert Hendrik Coetzee

    Coetzee, Gert Hendrik


    Steam gasification has been extensively researched in order to optimise and efficiently utilise coal. Reactivity on powdered coal has received considerable attention, however, due to equipment limitation large coal particle research has not progressed to the same extent. The lack of knowledge regarding the steam gasification reactivity of large coal particles is the main motivation of this study. A South African Highveld seam 4 coal was used in this investigation. Conventional ...

  5. Gasification of high ash, high ash fusion temperature bituminous coals

    Liu, Guohai; Vimalchand, Pannalal; Peng, WanWang


    This invention relates to gasification of high ash bituminous coals that have high ash fusion temperatures. The ash content can be in 15 to 45 weight percent range and ash fusion temperatures can be in C. to C. range as well as in excess of C. In a preferred embodiment, such coals are dealt with a two stage gasification process--a relatively low temperature primary gasification step in a circulating fluidized bed transport gasifier followed by a high temperature partial oxidation step of residual char carbon and small quantities of tar. The system to process such coals further includes an internally circulating fluidized bed to effectively cool the high temperature syngas with the aid of an inert media and without the syngas contacting the heat transfer surfaces. A cyclone downstream of the syngas cooler, operating at relatively low temperatures, effectively reduces loading to a dust filtration unit. Nearly dust- and tar-free syngas for chemicals production or power generation and with over 90%, and preferably over about 98%, overall carbon conversion can be achieved with the preferred process, apparatus and methods outlined in this invention.

  6. The ENCOAL Mild Coal Gasification Project, A DOE Assessment

    National Energy Technology Laboratory


    This report is a post-project assessment of the ENCOAL{reg_sign} Mild Coal Gasification Project, which was selected under Round III of the U.S. Department of Energy (DOE) Clean Coal Technology (CCT) Demonstration Program. The CCT Demonstration Program is a government and industry cofunded technology development effort to demonstrate a new generation of innovative coal utilization processes in a series of commercial-scale facilities. The ENCOAL{reg_sign} Corporation, a wholly-owned subsidiary of Bluegrass Coal Development Company (formerly SMC Mining Company), which is a subsidiary of Ziegler Coal Holding Company, submitted an application to the DOE in August 1989, soliciting joint funding of the project in the third round of the CCT Program. The project was selected by DOE in December 1989, and the Cooperative Agreement (CA) was approved in September 1990. Construction, commissioning, and start-up of the ENCOAL{reg_sign} mild coal gasification facility was completed in June 1992. In October 1994, ENCOAL{reg_sign} was granted a two-year extension of the CA with the DOE, that carried through to September 17, 1996. ENCOAL{reg_sign} was then granted a six-month, no-cost extension through March 17, 1997. Overall, DOE provided 50 percent of the total project cost of $90,664,000. ENCOAL{reg_sign} operated the 1,000-ton-per-day mild gasification demonstration plant at Triton Coal Company's Buckskin Mine near Gillette, Wyoming, for over four years. The process, using Liquids From Coal (LFC{trademark}) technology originally developed by SMC Mining Company and SGI International, utilizes low-sulfur Powder River Basin (PRB) coal to produce two new fuels, Process-Derived Fuel (PDF{trademark}) and Coal-Derived Liquids (CDL{trademark}). The products, as alternative fuel sources, are capable of significantly lowering current sulfur emissions at industrial and utility boiler sites throughout the nation thus reducing pollutants causing acid rain. In support of this overall

  7. Project Thunderbird: a nuclear trigger for coal gasification

    Use of nuclear explosions to facilitate utilization of coal, oil shale, and bituminous sand beds is reviewed, with particular attention to Project Thunderbird. A 100-mi2 region of Wyoming, underlain by more than 20,000 million tons of coal, is the site for this in situ coal-energy experimental program. The total coal interval lies at a depth of from 1000 to 2200 ft and contains a gross section of coal that may be the thickest in the Western Hemisphere. In Project Thunderbird, a nuclear explosion will open up multiple seams and overcome some problems experienced in previous underground gasification experiments. A collapse chimney of 25 to 30% void space could be formed, which would be burned under controlled conditions. A 50-kiloton nuclear device at 2200 ft in the base of the Fort Union coal-bearing unit will give the following chimney characteristics; a rubble chimney of broken rock with a radius of about 127 ft and a height of around 35 ft; and approximately 2,000,000 tons of broken rock of which 25% (or 500,000 tons) is coal (a Btu equivalency of 1.5 million barrels of oil). Ignition of the broken coal and controlled injection of oxygen into the chimney will produce low-Btu gas and associated products

  8. Japan`s sunshine project. 17.. 1992 annual summary of coal liquefaction and gasification


    This report describes the achievement of coal liquefaction and gasification technology development in the Sunshine Project for FY 1992. It presents the research and development of coal liquefaction which includes studies on reaction mechanism of coal liquefaction and catalysts for coal liquefaction, the research and development of coal gasification technologies which includes studies on gasification characteristics of various coals and improvement of coal gasification efficiency, the development of bituminous coal liquefaction which includes engineering, construction and operation of a bituminous coal liquefaction pilot plant and research by a process supporting unit (PSU), the development of brown coal liquefaction which includes research on brown coal liquefaction with a pilot plant and development of techniques for upgrading coal oil from brown coal, the development of common base technologies which includes development of slurry letdown valves and study on upgrading technology of coal-derived distillates, the development of coal-based hydrogen production technology with a pilot plant, the development of technology for entrained flow coal gasification, the assessment of coal hydrogasification, and the international co-operation. 4 refs., 125 figs., 39 tabs.

  9. Temporal measurements and kinetics of selenium release during coal combustion and gasification in a fluidized bed.

    Shen, Fenghua; Liu, Jing; Zhang, Zhen; Yang, Yingju


    The temporal release of selenium from coal during combustion and gasification in a fluidized bed was measured in situ by an on-line analysis system of trace elements in flue gas. The on-line analysis system is based on an inductively coupled plasma optical emission spectroscopy (ICP-OES), and can measure concentrations of trace elements in flue gas quantitatively and continuously. The results of on-line analysis suggest that the concentration of selenium in flue gas during coal gasification is higher than that during coal combustion. Based on the results of on-line analysis, a second-order kinetic law r(x)=0.94e(-26.58/RT)(-0.56 x(2) -0.51 x+1.05) was determined for selenium release during coal combustion, and r(x)=11.96e(-45.03/RT)(-0.53 x(2) -0.56 x+1.09) for selenium release during coal gasification. These two kinetic laws can predict respectively the temporal release of selenium during coal combustion and gasification with an acceptable accuracy. Thermodynamic calculations were conducted to predict selenium species during coal combustion and gasification. The speciation of selenium in flue gas during coal combustion differs from that during coal gasification, indicating that selenium volatilization is different. The gaseous selenium species can react with CaO during coal combustion, but it is not likely to interact with mineral during coal gasification. PMID:26897573

  10. CFD Analysis of Coal and Heavy Oil Gasification for Syngas Production

    Sreedharan, Vikram


    This work deals with the gasification of coal and heavy oil for syngas production using Computational Fluid Dynamics (CFD). Gasification which includes complex physical and chemical processes such as turbulence, multiphase flow, heat and mass transfer and chemical reactions has been modeled using a...... phases. Gasification consists of the processes of passive heating, devolatilization, volatiles oxidation, char gasification and gas phase reactions. Attention is given here to the chemical kinetics of the gasification processes. The coal gasification model has been validated for entrained-flow gasifiers...... carbon iv dioxide is overestimated. The deviation is fairly small, particularly for the improved chemical kinetics scheme. The heavy oil gasification model has been validated for a pilot-scale entrained-flow gasifier operating under different oxygen ratios. A gasification model similar to that developed...


    Vas Choudhry; Stephen Kwan; Steven R. Hadley


    The objective of the project entitled ''Utilization of Lightweight Materials Made from Coal Gasification Slags'' was to demonstrate the technical and economic viability of manufacturing low-unit-weight products from coal gasification slags which can be used as substitutes for conventional lightweight and ultra-lightweight aggregates. In Phase I, the technology developed by Praxis to produce lightweight aggregates from slag (termed SLA) was applied to produce a large batch (10 tons) of expanded slag using pilot direct-fired rotary kilns and a fluidized bed calciner. The expanded products were characterized using basic characterization and application-oriented tests. Phase II involved the demonstration and evaluation of the use of expanded slag aggregates to produce a number of end-use applications including lightweight roof tiles, lightweight precast products (e.g., masonry blocks), structural concrete, insulating concrete, loose fill insulation, and as a substitute for expanded perlite and vermiculite in horticultural applications. Prototypes of these end-use applications were made and tested with the assistance of commercial manufacturers. Finally, the economics of expanded slag production was determined and compared with the alternative of slag disposal. Production of value-added products from SLA has a significant potential to enhance the overall gasification process economics, especially when the avoided costs of disposal are considered.

  12. NETL, USDA design coal-stabilized biomass gasification unit



    Coal, poultry litter, contaminated corn, rice hulls, moldly hay, manure sludge - these are representative materials that could be tested as fuel feedstocks in a hybrid gasification/combustion concept studied in a recent US Department of Energy (DOE) design project. DOE's National Energy Technology Laboratory (NETL) and the US Department of Agriculture (USDA) collaborated to develop a design concept of a power system that incorporates Hybrid Biomass Gasification. This system would explore the use of a wide range of biomass and agricultural waste products as gasifier feedstocks. The plant, if built, would supply one-third of electrical and steam heating needs at the USDA's Beltsville (Maryland) Agricultural Research Center. 1 fig., 1 photo.

  13. Environmental control aspects of in situ coal gasification: ground-water quality changes and subsidence effects

    Mead, S.W.


    Research progress for FY 1980 is reported. The effects of in situ coal gasification (now called Underground Coal Gasification - UCG) on ground water quality are being investigated. The subsurface ground movement and surface subsidence associated with UCG are also being studied. Measurements show that organic contaminants are concentrated in a shell just outside the burn boundary. (ACR)

  14. Wabash River Coal Gasification Repowering Project: A DOE Assessment

    National Energy Technology Laboratory


    The goal of the U.S. Department of Energy (DOE) Clean Coal Technology Program (CCT) is to furnish the energy marketplace with a number of advanced, more efficient, and environmentally responsible coal utilization technologies through demonstration projects. These projects seek to establish the commercial feasibility of the most promising advanced coal technologies that have developed beyond the proof-of-concept stage. This document serves as a DOE post-project assessment (PPA) of a project selected in CCT Round IV, the Wabash River Coal Gasification Repowering (WRCGR) Project, as described in a Report to Congress (U.S. Department of Energy 1992). Repowering consists of replacing an existing coal-fired boiler with one or more clean coal technologies to achieve significantly improved environmental performance. The desire to demonstrate utility repowering with a two-stage, pressurized, oxygen-blown, entrained-flow, integrated gasification combined-cycle (IGCC) system prompted Destec Energy, Inc., and PSI Energy, Inc., to form a joint venture and submit a proposal for this project. In July 1992, the Wabash River Coal Gasification Repowering Project Joint Venture (WRCGRPJV, the Participant) entered into a cooperative agreement with DOE to conduct this project. The project was sited at PSI Energy's Wabash River Generating Station, located in West Terre Haute, Indiana. The purpose of this CCT project was to demonstrate IGCC repowering using a Destec gasifier and to assess long-term reliability, availability, and maintainability of the system at a fully commercial scale. DOE provided 50 percent of the total project funding (for capital and operating costs during the demonstration period) of $438 million. Construction for the demonstration project was started in July 1993. Pre-operational tests were initiated in August 1995, and construction was completed in November 1995. Commercial operation began in November 1995, and the demonstration period was completed in

  15. Wabash River Coal Gasification Repowering Project: A DOE Assessment; FINAL

    The goal of the U.S. Department of Energy (DOE) Clean Coal Technology Program (CCT) is to furnish the energy marketplace with a number of advanced, more efficient, and environmentally responsible coal utilization technologies through demonstration projects. These projects seek to establish the commercial feasibility of the most promising advanced coal technologies that have developed beyond the proof-of-concept stage. This document serves as a DOE post-project assessment (PPA) of a project selected in CCT Round IV, the Wabash River Coal Gasification Repowering (WRCGR) Project, as described in a Report to Congress (U.S. Department of Energy 1992). Repowering consists of replacing an existing coal-fired boiler with one or more clean coal technologies to achieve significantly improved environmental performance. The desire to demonstrate utility repowering with a two-stage, pressurized, oxygen-blown, entrained-flow, integrated gasification combined-cycle (IGCC) system prompted Destec Energy, Inc., and PSI Energy, Inc., to form a joint venture and submit a proposal for this project. In July 1992, the Wabash River Coal Gasification Repowering Project Joint Venture (WRCGRPJV, the Participant) entered into a cooperative agreement with DOE to conduct this project. The project was sited at PSI Energy's Wabash River Generating Station, located in West Terre Haute, Indiana. The purpose of this CCT project was to demonstrate IGCC repowering using a Destec gasifier and to assess long-term reliability, availability, and maintainability of the system at a fully commercial scale. DOE provided 50 percent of the total project funding (for capital and operating costs during the demonstration period) of$438 million. Construction for the demonstration project was started in July 1993. Pre-operational tests were initiated in August 1995, and construction was completed in November 1995. Commercial operation began in November 1995, and the demonstration period was completed in December

  16. Second Advanced Coal Gasification Symposium: Introduction

    This introductory paper presents an energy picture in China, including the present situation and the future prospects, as well as measures to be taken. The paper first describes the energy resources and reserves of China. Energy consumption is: coal - 71%; petroleum - 22%; water power - 4%; and natural gas - 3%. A resource appraisal was performed to find the best ways of utilizing China's energy sources. Besides the four mentioned above, nuclear power, biogas, biomass liquefaction, and other renewable energy sources were appraised. The paper then discussed plans for resource exploitation, conversion, and utilization and plans for energy conservation in transportation sectors and waste energy utilization

  17. Experimental investigation of high temperature and high pressure coal gasification

    Highlights: ► Gasification kinetics at temperature up to 1600 °C and pressure up to 0.5 MPa. ► Experimental investigation of pyrolysis under realistic conditions. ► Experiments in lab-scale using three different setups. ► Comparison of lab-scale data to experimental results from a pilot-scale gasifier. -- Abstract: Pyrolysis and gasification behavior is analyzed at operation conditions relevant to industrial scale entrained flow gasifiers. A wire mesh reactor and the Pressurized High Temperature Entrained Flow Reactor (PiTER) are used to measure volatile yield of Rhenish lignite, a bituminous coal and German anthracite at high temperature and high pressure. In the wire mesh reactor at 1000 °C a significant influence of pressure on volatile yield is observed. For lignite the volatile yield (daf) decreases from 57 wt% at atmospheric pressure to 53 wt% at 5.0 MPa. In the same pressure interval the volatile yield of the bituminous coal strongly decreases, whereas no significant influence of pressure on the volatile yield of anthracite is detected. In entrained flow experiments (PiTER) at higher temperature and 0.5 MPa an enhanced devolatilization of the lignite is observed. At 1200 °C, the maximum volatile yield is 62 wt% and it increases to 67 wt% at 1400 °C. In entrained flow gasification experiments with Rhenish lignite a high level of conversion is measured at atmospheric pressure and at 0.5 MPa. At both pressures, coal conversion increases with temperature and residence time. The highest conversion of 96 wt% is achieved at a particle residence time of 1.3 s, at a temperature of 1600 °C, and a pressure of 0.5 MPa. The experimental results show a large influence of operation parameters on pyrolysis and gasification behavior of Rhenish lignite. The volatile release in the pyrolysis stage and the high level of conversion after a short residence time indicate that Rhenish lignite is suitable for gasification in an entrained flow reactor. The reactivities

  18. Modeling of Contaminant Migration through Porous Media after Underground Coal Gasification in Shallow Coal Seam

    Soukup, Karel; Hejtmánek, Vladimír; Čapek, P.; Stanczyk, K.; Šolcová, Olga


    Roč. 140, DEC (2015), s. 188-197. ISSN 0378-3820 Grant ostatní: RFCS(XE) RFCR-CT-2011-00002 Institutional support: RVO:67985858 Keywords : underground coal gasification * transport phenomena modeling * transport parameters Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 3.352, year: 2014

  19. Energetic and exergetic performance assessment of some coals in Turkey for gasification process

    Ozturk, M.; Ozek, N.; Yuksel, Y.E. [Suleyman Demirel University, Isparta (Turkey). Dept. of Physics


    This paper undertakes a study on energetic and exergetic performance evaluation of various types of coals in Turkey, such as Armutcuk, Amasra, Zonguldak and Catalagzi hard coals and Tuncbilek, Beypazari, Cayirhan, Afsin, Soma, Yatagan, Can and Sorgun lignites for gasification purposes, where syn-gas may subsequently be used for the production of electricity, heat, hydrogen, etc. in industry. The chemical exergy contents of these coals are determined and compared for a potential use in gasification, and their energetic and exergetic efficiencies are also assessed for performance comparison. In the analysis, exergetic efficiencies are evaluated for an idealised gasifier in which chemical equilibrium is reached, ashes of coals are not considered and heat losses are neglected. It is observed that coals having lower heating value have higher gasification efficiency, and the ratios of hydrogen to chemical exergy of coal are related to the gasification process efficiencies of this coal.

  20. Project report on coal gasification by nuclear process heat. Phase 2

    The process heat of a HTR is used for conversion of coal to the energy sources H2, MeOH, and SNG. The nuclear gasification processes (non-catalytic steam gasification, catalytic steam gasification, hydrogenation) are compared with the autothermal coal gasification techniques (Texaco, Lurgi). The results of the study show the technical feasibility of the steam gasification process. Cost-benefit analyses show the cost ratios of the nuclear gasification processes to be higher than those of the autothermal processes. Investigations on improvement potentials of the steam gasification process did show possible economic efficiency enhancement, but cost ratios still are above those of the autothermal techniques. In addition, there is need for better or even optimised adjustment of HTR operation to the requirements of the relevant nuclear process heat applications. (orig.) With 6 refs., 11 tabs., 11 figs

  1. Study on CO2 gasification reactivity and physical characteristics of biomass, petroleum coke and coal chars.

    Huo, Wei; Zhou, Zhijie; Chen, Xueli; Dai, Zhenghua; Yu, Guangsuo


    Gasification reactivities of six different carbonaceous material chars with CO2 were determined by a Thermogravimetric Analyzer (TGA). Gasification reactivities of biomass chars are higher than those of coke and coal chars. In addition, physical structures and chemical components of these chars were systematically tested. It is found that the crystalline structure is an important factor to evaluate gasification reactivities of different chars and the crystalline structures of biomass chars are less order than those of coke and coal chars. Moreover, initial gasification rates of these chars were measured at high temperatures and with relatively large particle sizes. The method of calculating the effectiveness factor η was used to quantify the effect of pore diffusion on gasification. The results show that differences in pore diffusion effects among gasification with various chars are prominent and can be attributed to different intrinsic gasification reactivities and physical characteristics of different chars. PMID:24642484

  2. Investigation of non-isothermal and isothermal gasification process of coal char using different kinetic model

    Wang Guangwei; Zhang Jianliang; Shao Jiugang; Li Kejiang; Zuo Haibin


    Isothermal and non-isothermal gasification kinetics of coal char were investigated by using thermogravi-metric analysis (TGA) in CO2 atmosphere, and the experimental data were interpreted with the aids of random pore model (RPM), unreacted shrinking core model (URCM) and volume model (VM). With the increase of heating rate, gasification curve moves into high temperature zone and peak rate of gasification increases;with the increase of gasification temperature, gasification rate increases and the total time of gasification is shortened. The increase of both heating rate and gasification temperature could improve gasification process of coal char. Kinetics analysis indicates that experimental data agree better with the RPM than with the other two models. The apparent activation energy of non-isothermal and isother-mal gasification of coal char using RPM is 193.9 kJ/mol and 212.6 kJ/mol respectively, which are in accor-dance with reported data. Gasification process of coal char under different heating rates and different temperatures are predicted by the RPM derived in this study, and it is found that the RPM predicts the reaction process satisfactorily.

  3. A continuous two stage solar coal gasification system

    Mathur, V. K.; Breault, R. W.; Lakshmanan, S.; Manasse, F. K.; Venkataramanan, V.

    The characteristics of a two-stage fluidized-bed hybrid coal gasification system to produce syngas from coal, lignite, and peat are described. Devolatilization heat of 823 K is supplied by recirculating gas heated by a solar receiver/coal heater. A second-stage gasifier maintained at 1227 K serves to crack remaining tar and light oil to yield a product free from tar and other condensables, and sulfur can be removed by hot clean-up processes. CO is minimized because the coal is not burned with oxygen, and the product gas contains 50% H2. Bench scale reactors consist of a stage I unit 0.1 m in diam which is fed coal 200 microns in size. A stage II reactor has an inner diam of 0.36 m and serves to gasify the char from stage I. A solar power source of 10 kWt is required for the bench model, and will be obtained from a central receiver with quartz or heat pipe configurations for heat transfer.

  4. Transport phenomena in underground coal gasification channels (transportverschijnselen in ondergrondse kolenvergassingskanalen). Doctoral thesis

    Kuyper, R.A.


    Underground coal gasification is an attractive option to recover energy from thin deep-lying coal seams. By injecting air into the coal layer, combustible gases are formed underground which can be used to produce energy at the surface. During a coal gasification field test in Pricetown (USA), an open channel structure had formed underground. In this thesis, the wide range of transport processes occurring in such underground coal gasification channels has been studied. The principal aim of this study was to understand and describe the transport processes which determine the behavior of the gasification process. The main aspects of the gasification process have been studied separately. Due to this approach, the influence of the various aspects of the gasification process on the behavior of the process has become clear. In the first part of this thesis, the influence of geometrical aspects of the gasification channel on the natural-convection flow in the channel has been studied by considering the natural-convection flow in various differentially heated enclosures. This approach led to a fundamental study on natural-convection flows. The second part of this thesis is associated with the transport processes arising during gasification. Here, a simulation model has been refined step by step. In the final simulation model, all main transport processes occurring in a rectangular gasification channel are described.

  5. Air-steam gasification of different types of coals using fluidised bed gasifier

    Othman, N.F. [TNB Research Sdn. Bhd., Kawasan Inst. Penyelidikan, Selangor Darul Ehsan (Malaysia); Bosrooh, M.H.; Majid, K.A. [Tenaga National Univ., Selangor (Malaysia)


    Coal gasification has been touted as being the cleanest technology for producing energy from coal. The coal reserve in Malaysia is 1712 million tonnes of coal ranging from lignite to anthracite. Lignite and sub-bituminous coals have shown potential to be easily gasified and suitable for Integrated Gasification Combined Cycle (IGCC) power generation. This laboratory study investigated the gasification of Adaro, DEJ, Hunter Valley, Merit Pila and Mukah Balingian coals. The study made use of an atmospheric fluidized bed gasifier using air and air-steam as the fluidizing media. Gas chromatography was used to determination the producer gas compositions. The gasification experiments were conducted at a bed temperature of 600 degrees C. The influence of air and steam as the gasifying agents in the gasification process was studied, and the producer gas compositions were compared according to the type of gasifying agent. Air-steam gasification revealed a significant increase in carbon monoxide, carbon dioxide, methane and hydrogen content in the producer gas compared with the air gasification. The study also showed that hydrogen, carbon monoxide and methane were significantly higher in the sub-bituminous coal than in the bituminous coal. The quality of the producer gas improved, as steam was introduced as the gasifying agent. 10 refs., 4 tabs., 2 figs.

  6. Wabash River Coal Gasification Repowering Project. Topical report, July 1992--December 1993


    The Wabash River Coal Gasification Repowering Project (WRCGRP, or Wabash Project) is a joint venture of Destec Energy, Inc. of Houston, Texas and PSI Energy, Inc. of Plainfield, Indiana, who will jointly repower an existing 1950 vintage coal-fired steam generating plant with coal gasification combined cycle technology. The Project is located in West Terre Haute, Indiana at PSI`s existing Wabash River Generating Station. The Project will process locally-mined Indiana high-sulfur coal to produce 262 megawatts of electricity. PSI and Destec are participating in the Department of Energy Clean Coal Technology Program to demonstrate coal gasification repowering of an existing generating unit affected by the Clean Air Act Amendments. As a Clean Coal Round IV selection, the project will demonstrate integration of an existing PSI steam turbine generator and auxiliaries, a new combustion turbine generator, heat recovery steam generator tandem, and a coal gasification facility to achieve improved efficiency, reduced emissions, and reduced installation costs. Upon completion in 1995, the Project will not only represent the largest coal gasification combined cycle power plant in the United States, but will also emit lower emissions than other high sulfur coal-fired power plants and will result in a heat rate improvement of approximately 20% over the existing plant configuration. As of the end of December 1993, construction work is approximately 20% complete for the gasification portion of the Project and 25% complete for the power generation portion.

  7. Computational fluid dynamics modeling of coal gasification in a pressurized spout-fluid bed

    Zhongyi Deng; Rui Xiao; Baosheng Jin; He Huang; Laihong Shen; Qilei Song; Qianjun Li [Southeast University, Nanjing (China). Key Laboratory of Clean Coal Power Generation and Combustion Technology of Ministry of Education


    Computational fluid dynamics (CFD) modeling, which has recently proven to be an effective means of analysis and optimization of energy-conversion processes, has been extended to coal gasification in this paper. A 3D mathematical model has been developed to simulate the coal gasification process in a pressurized spout-fluid bed. This CFD model is composed of gas-solid hydrodynamics, coal pyrolysis, char gasification, and gas phase reaction submodels. The rates of heterogeneous reactions are determined by combining Arrhenius rate and diffusion rate. The homogeneous reactions of gas phase can be treated as secondary reactions. A comparison of the calculated and experimental data shows that most gasification performance parameters can be predicted accurately. This good agreement indicates that CFD modeling can be used for complex fluidized beds coal gasification processes. 37 refs., 7 figs., 5 tabs.

  8. Alloy selection for sulfidation: oxidation resistance in coal gasification environments

    Bradshaw, R.W.; Stoltz, R.E.


    A series of iron-nickel-chromium and nickel-chromium alloys were studied for their combined sulfidation-oxidation resistance in simulated coal gasification environments. All alloys contained a minimum of 20 w/o chromium, and titanium and aluminum in the range 0 to 4 w/o. Corrosion resistance was evaluated at 1255/sup 0/K (1800/sup 0/F) in both high BTU and low BTU coal gasification atmospheres with 1 v/o H/sub 2/S. Titanium at levels greater than 1 w/o imparted significant sulfidation resistance due to an adherent, solid solution chromium-titanium oxide layer which prevented sulfur penetration. Aluminum was less effective in preventing sulfidation since surface scales were not adherent. Of the commercial alloys tested, Nimomic 81, Pyromet 31, IN801, and IN825 exhibited the best overall corrosion resistance. However, futher alloy development, tailored to produce solid solution chromium-titanium oxide scales, may lead to alloys with greater sulfidation-oxidation resistance than those investigated here.

  9. Electricity production by way of coal gasification in Vresova plant

    Buryan, P.; Vejvoda, J [Institute of Chemical Technology, Prague (Czech Republic). Faculty of Environmental Technology, Dept. of Coke, Gas and Air Prevention


    The paper deals with the retrofit town gas works into the Vresova power plant in the Czech Republic supplying electricity and heat, in which gas from gasification is used for electricity production in gas-turbine cycle. Gas from gasification of the coal is cleaned at elevated pressure by the Rectisol process and the gases containing H{sub 2}S, COS and CS{sub 2} are combusted. Flue gas is first treated by the selective catalytic reduction process using ammonia to remove NOx. The second stage of flue gas cleaning is catalytic oxidation of SO{sub 2} to SO{sub 32} followed by sulphuric acid production. The quality of catalyst is described and some data about the economy of process presented. The paper describes processes mentioned, experiences with operation and compares them with other processes of energy production such as atmospheric and pressurised fluidised bed combustion, PCC, IGCC and GCCT and pulverised coal combustion with limestone FGD technology. 4 refs., 2 figs., 4 tabs.

  10. Gasification in pulverized coal flames. Final report (Part I). Pulverized coal combustion and gasification in a cyclone reactor: experiment and model

    Barnhart, J. S.; Laurendeau, N. M.


    A unified experimental and analytical study of pulverized coal combustion and low-BTU gasification in an atmospheric cyclone reactor was performed. Experimental results include several series of coal combustion tests and a coal gasification test carried out via fuel-rich combustion without steam addition. Reactor stability was excellent over a range of equivalence ratios from .67 to 2.4 and air flowrates from 60 to 220 lb/hr. Typical carbon efficiencies were 95% for air-rich and stoichiometric tests and 80% for gasification tests. The best gasification results were achieved at an equivalence ratio of 2.0, where the carbon, cold gas and hot gas efficiencies were 83, 45 and 75%, respectively. The corresponding product gas heating value was 70 BTU/scf. A macroscopic model of coal combustion in the cyclone has been developed. Fuel-rich gasification can also be modeled through a gas-phase equilibrium treatment. Fluid mechanics are modeled by a particle force balance and a series combination of a perfectly stirred reactor and a plug flow reactor. Kinetic treatments of coal pyrolysis, char oxidation and carbon monoxide oxidation are included. Gas composition and temperature are checked against equilibrium values. The model predicts carbon efficiency, gas composition and temperature and reactor heat loss; gasification parameters, such as cold and hot gas efficiency and make gas heating value, are calculated for fuel-rich conditions. Good agreement exists between experiment and theory for conditions of this investigation.

  11. Gasification Characteristics of Coal/Biomass Mixed Fuels

    Mitchell, Reginald


    A research project was undertaken that had the overall objective of developing the models needed to accurately predict conversion rates of coal/biomass mixtures to synthesis gas under conditions relevant to a commercially-available coal gasification system configured to co- produce electric power as well as chemicals and liquid fuels. In our efforts to accomplish this goal, experiments were performed in an entrained flow reactor in order to produce coal and biomass chars at high heating rates and temperatures, typical of the heating rates and temperatures fuel particles experience in real systems. Mixed chars derived from coal/biomass mixtures containing up to 50% biomass and the chars of the pure coal and biomass components were subjected to a matrix of reactivity tests in a pressurized thermogravimetric analyzer (TGA) in order to obtain data on mass loss rates as functions of gas temperature, pressure and composition as well as to obtain information on the variations in mass specific surface area during char conversion under kinetically-limited conditions. The experimental data were used as targets when determining the unknown parameters in the chemical reactivity and specific surface area models developed. These parameters included rate coefficients for the reactions in the reaction mechanism, enthalpies of formation and absolute entropies of adsorbed species formed on the carbonaceous surfaces, and pore structure coefficients in the model used to describe how the mass specific surface area of the char varies with conversion. So that the reactivity models can be used at high temperatures when mass transport processes impact char conversion rates, Thiele modulus – effectiveness factor relations were also derived for the reaction mechanisms developed. In addition, the reactivity model and a mode of conversion model were combined in a char-particle gasification model that includes the effects of chemical reaction and diffusion of reactive gases through particle


    Gopala N. Krishnan; Ripudaman Malhotra; Angel Sanjurjo


    Heat-exchangers, particle filters, turbines, and other components in integrated coal gasification combined cycle system must withstand the highly sulfiding conditions of the high temperature coal gas over an extended period of time. The performance of components degrades significantly with time unless expensive high alloy materials are used. Deposition of a suitable coating on a low cost alloy may improve is resistance to such sulfidation attack and decrease capital and operating costs. The alloys used in the gasifier service include austenitic and ferritic stainless steels, nickel-chromium-iron alloys, and expensive nickel-cobalt alloys. A review of the literature indicated that the Fe- and Ni-based high-temperature alloys are susceptible to sulfidation attack unless they are fortified with high levels of Cr, Al, and Si. To impart corrosion resistance, these elements need not be in the bulk of the alloy and need only be present at the surface layers. We selected diffusion coatings of Cr and Al, and surface coatings of Si and Ti for the preliminary testing. These coatings will be applied using the fluidized bed chemical vapor deposition technique developed at SRI which is rapid and relatively inexpensive. We have procured coupons of typical alloys used in a gasifier. These coupons will be coated with Cr, Al, Si, and Ti. The samples will be tested in a bench-scale reactor using simulated coal gas compositions. In addition, we will be sending coated samples for insertion in the gas stream of the coal gasifier.

  13. Status of health and environmental research relative to coal gasification 1976 to the present

    Wilzbach, K.E.; Reilly, C.A. Jr. (comps.)


    Health and environmental research relative to coal gasification conducted by Argonne National Laboratory, the Inhalation Toxicology Research Institute, and Oak Ridge National Laboratory under DOE sponsorship is summarized. The studies have focused on the chemical and toxicological characterization of materials from a range of process streams in five bench-scale, pilot-plant and industrial gasifiers. They also address ecological effects, industrial hygiene, environmental control technology performance, and risk assessment. Following an overview of coal gasification technology and related environmental concerns, integrated summaries of the studies and results in each area are presented and conclusions are drawn. Needed health and environmental research relative to coal gasification is identified.

  14. Toxicologic studies of emissions from coal gasification process. I. Subchronic feeding studies.

    Kostial, K; Kello, D; Blanusa, M; Maljković, T; Rabar, I; Bunarević, A; Stara, J F


    The increasing use of new sources of energy may result in additional contamination of the human environment with inorganic and organic pollutants which are not yet adequately investigated with regard to their potential impact on human health. However, some evidence exists that several trace inorganic and organic contaminants found in coal processing residues may constitute potential health problems. Therefore, the comparative biological hazards of solid wastes and effluents from a Lurgi coal gasification plant were initially evaluated using acute and chronic feeding experiments in male and female rats. In the subchronic experiment, six-week old animals were fed diets wih various levels of ash (slag) additive (0.5%, 1%, and 5%) for period of 16 weeks. Following exposure, blood samples were taken and 22-hour urine samples were collected. Livers and kidneys, and testicles in males, were taken for trace element analysis or histologic examination. The urinary values, erythrocyte and leucocyte count, hemoglobin, packed cell volume, and concentration of trace elements in exposed animals were determined. The addition of ash (slag) to the diet in concentrations much higher than expected in conditions of environmental contamination had no measurable health effects. Although these initial results obtained in relatively short-term experiments cannot be directly extrapolated to human health effects, particularly not for carcinogenic assessment, there is an indication that exposure to solid wastes from the coal gasification plant may not be toxic. PMID:7462912

  15. Numerical investigation on performance of coal gasification under various injection patterns in an entrained flow gasifier

    Highlights: ► A numerical method is developed to predict coal gasification phenomena. ► Particular emphasis is placed on the influence of injection pattern upon syngas production. ► The parameter of steam/coal ratio is also taken into account. ► The appropriate injection for the performance of coal gasification is suggested. ► The obtained results have provided a useful insight into the operation of coal gasification. -- Abstract: Gasification plays an important role in the development of clean coal technology. To seek appropriate operations for synthesis gas (syngas) formation, the present study develops a numerical method to predict coal gasification phenomena in an entrained-flow gasifier. Particular emphasis is placed on the influence of injection pattern upon syngas production. The parameter of steam/coal ratio is also taken into account to evaluate its impact on hydrogen generation. The simulations suggest that the developed numerical method is able to provide an accurate prediction on syngas formation. With oxygen injected from the center inlet and coal from the middle ring inlet of the reactor, the operating pattern gives the best performance of coal gasification where the carbon conversion (CC) and coal gas efficiency (CGE) are 89% and 72%, respectively. Increasing steam into the reactor reduces CC and less CO is generated. Nevertheless, more H2 is produced stemming from water gas shift reaction. This results in slight variation in CGE with altering steam/coal ratio. The obtained results have provided a useful insight into the operation of fuel and oxidant injection for coal gasification.

  16. An overview of underground coal gasification and its applicability for Turkish lignite

    Pekpak, E.; Yoncaci, S.; Kilic, M.G. [Middle East Technical Univ., Ankara (Turkey). Dept. of Mining Engineering


    Coal is expected to maintain its significance as an energy source for a longer time period than oil and natural gas. Environmental concerns have led to the development of clean coal technologies, such as coal gasification. Coal gasification can be used at either at surface or in underground coal gasification (UCG). UCG has several advantages over surface gasification and conventional mining such as rank low calorific value coals. Coal gasification also has the potential to contribute to the energy supply of a country. Most Turkish coals are lignite and UCG may enable diversification of energy sources of Turkey and may help decrease external dependency on energy. This paper presented a study that matched a UCG technique to the most appropriate (Afsin Elbistan) lignite reserve in Turkey. Two UCG techniques were presented, including the linked vertical well method, and the directional drilling-controlled retractable injection point (CRIP) method. The properties of coal seams and coal properties were also outlined. It was concluded that Cobanbey is the most preferable sector in the Elbistan Lignite Reserve for a pilot study, and that the linked vertical well method could be considered as a candidate method. 17 refs., 6 tabs., 1 fig.

  17. Thermal-Hydrological Sensitivity Analysis of Underground Coal Gasification

    Buscheck, T A; Hao, Y; Morris, J P; Burton, E A


    This paper presents recent work from an ongoing project at Lawrence Livermore National Laboratory (LLNL) to develop a set of predictive tools for cavity/combustion-zone growth and to gain quantitative understanding of the processes and conditions (natural and engineered) affecting underground coal gasification (UCG). We discuss the application of coupled thermal-hydrologic simulation capabilities required for predicting UCG cavity growth, as well as for predicting potential environmental consequences of UCG operations. Simulation of UCG cavity evolution involves coupled thermal-hydrological-chemical-mechanical (THCM) processes in the host coal and adjoining rockmass (cap and bedrock). To represent these processes, the NUFT (Nonisothermal Unsaturated-saturated Flow and Transport) code is being customized to address the influence of coal combustion on the heating of the host coal and adjoining rock mass, and the resulting thermal-hydrological response in the host coal/rock. As described in a companion paper (Morris et al. 2009), the ability to model the influence of mechanical processes (spallation and cavity collapse) on UCG cavity evolution is being developed at LLNL with the use of the LDEC (Livermore Distinct Element Code) code. A methodology is also being developed (Morris et al. 2009) to interface the results of the NUFT and LDEC codes to simulate the interaction of mechanical and thermal-hydrological behavior in the host coal/rock, which influences UCG cavity growth. Conditions in the UCG cavity and combustion zone are strongly influenced by water influx, which is controlled by permeability of the host coal/rock and the difference between hydrostatic and cavity pressure. In this paper, we focus on thermal-hydrological processes, examining the relationship between combustion-driven heat generation, convective and conductive heat flow, and water influx, and examine how the thermal and hydrologic properties of the host coal/rock influence those relationships

  18. Gasification of Coal-Oil and Coal-Water-Oil Slurries in a Fluidized Bed Reactor

    Svoboda, Karel; Pohořelý, Michael; Jeremiáš, Michal; Kameníková, Petra; Hartman, Miloslav

    Bratislava : Slovak University of Technology , 2010 - (Markoš, J.), s. 97 ISBN 978-80-227-3290-1. [International Conference of Slovak Society of Chemical Engineering /37./. Tatranské Matliare (SK), 24.05.2010-28.05.2010] R&D Projects: GA MŠk 2B08048 Grant ostatní: RFCR(XE) CT/2007/00005 Institutional research plan: CEZ:AV0Z40720504 Keywords : fluidized bed * gasification * coal Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  19. Corrosion and mechanical behavior of materials for coal gasification applications

    Natesan, K.


    A state-of-the-art review is presented on the corrosion and mechanical behavior of materials at elevated temperatures in coal-gasification environments. The gas atmosphere in coal-conversion processes are, in general, complex mixtures which contain sulfur-bearing components (H/sub 2/S, SO/sub 2/, and COS) as well as oxidants (CO/sub 2//CO and H/sub 2/O/H/sub 2/). The information developed over the last five years clearly shows sulfidation to be the major mode of material degradation in these environments. The corrosion behavior of structural materials in complex gas environments is examined to evaluate the interrelationships between gas chemistry, alloy chemistry, temperature, and pressure. Thermodynamic aspects of high-temperature corrosion processes that pertain to coal conversion are discussed, and kinetic data are used to compare the behavior of different commercial materials of interest. The influence of complex gas environments on the mechanical properties such as tensile, stress-rupture, and impact on selected alloys is presented. The data have been analyzed, wherever possible, to examine the role of environment on the property variation. The results from ongoing programs on char effects on corrosion and on alloy protection via coatings, cladding, and weld overlay are presented. Areas of additional research with particular emphasis on the development of a better understanding of corrosion processes in complex environments and on alloy design for improved corrosion resistance are discussed. 54 references, 65 figures, 24 tables.

  20. Public perceptions of underground coal gasification in the United Kingdom

    There is growing interest internationally in the technology of Underground Coal Gasification (UCG) as a means of accessing the energy contained within inaccessible coal reserves. One of the potential obstacles to UCG deployment is adverse public perceptions and reactions, either stopping or delaying proposed applications. This paper explores the public perceptions of UCG in the UK through a detailed case-study and focus group discussion. A failed proposal for a UCG drill site at Silverdale (Staffordshire) provides an opportunity to understand the influence of local social, cultural and institutional factors on the manner in which the risks and benefits associated with UCG are perceived. The participants of the focus group recognised the potential of UCG as a secure source of energy for the UK in the future, provided that it is safe to humans and the environment and cost-effective. The group discussed potential benefits to the local community, potential risks, the role of carbon dioxide capture and storage, and links to the hydrogen economy. The group recommended that an open, transparent and consultative process of decision-making and operation should be adopted by the developer, operator and regulator; and that UCG should be developed at a remote site, preferably on land, before applying it in coal seams close to populated areas

  1. Coal gasification. Quarterly report, January-March 1979. [US DOE supported



    Progress in DOE-supported coal gasification pilot plant projects is reported: company, location, contract number, funding, process description, history and progress in the current quarter. Two support projects are discussed: preparation of a technical data book and mathematical modeling of gasification reactors. (LTN)

  2. Fixed-bed gasification research using US coals. Volume 16. Gasification of 2-inch Minnesota peat sods

    Thimsen, D.; Maurer, R.E.; Pooler, A.R.; Pui, D.; Liu, B.; Kittelson, D.


    A single, fixed-bed Wellman-Galusha gasifier coupled with a hot, raw gas combustion system and scubber used to gasify numerous coals from throughout the United States. The gasification test program is organized as a cooperative effort by private industrial participants and government agencies. The consortium of participants is organized under the Mining and Industrial Fuel Gas (MIFGa) group. This report is the sixteenth volume in a series of reports describing the atmospheric pressure, fixed-bed gasification of US coals. This specific test report describes the gasification of two-inch Minnesota peat sods, which began on June 24, 1985 and was completed on June 27, 1985. 4 refs., 18 figs., 14 tabs.

  3. Investigations of gas explosions in a nuclear coal gasification plant

    The safety research program on gas cloud explosions is performed in the context of the German project of the Prototype Plant Nuclear Process Heat. By the work within this project, it is tried to extend the use of nuclear energy to non-electric application. The programme comprises efforts in several scientific disciplines. The final goal is to provide a representative pressure-time-function or a set of such functions. These functions should be the basis for safe design and construction of the nuclear reactor system of a coal gasification plant. No result yet achieved contradicts the assumption that released process gas is only able to deflagrate. It should be possible to demonstrate that, if unfavourable configurations are avoided, a design pressure of 300 mbar is sufficient to withstand an explosion of process gas; this pressure should never be exceeded by process gas explosions irrespective of gas mass released and distance to release point, except possibly in relatively small areas

  4. Materials for coal gasification effects of environment on properties


    Although this testing program is incomplete, it is possible to reach a few tentative conclusions concerning the suitability of some of the candidate alloys for structural applications in coal gasification environments. The high cobalt alloys clearly showed the best stress-rupture strengths at 1800F in CGA. At 1200 and 1500F, several alloys show reasonable stress-rupture strengths in CGA. The tensile test results obtained to date indicate no major problems, although CGA exposures do have a detrimental effect on ductilities for a number of the alloys and weldments tested. The very low room-temperature impact energies of some of the alloys and the general degradation in impact properties with extend elevated-temperature exposures are also causes for concern.

  5. Proceedings of the ninth annual underground coal gasification symposium

    Wieber, P.R.; Martin, J.W.; Byrer, C.W. (eds.)


    The Ninth Underground Coal Gasification Symposium was held August 7 to 10, 1983 at the Indian Lakes Resort and Conference Center in Bloomingdale, Illinois. Over one-hundred attendees from industry, academia, National Laboratories, State Government, and the US Government participated in the exchange of ideas, results and future research plans. Representatives from six countries including France, Belgium, United Kingdom, The Netherlands, West Germany, and Brazil also participated by presenting papers. Fifty papers were presented and discussed in four formal sessions and two informal poster sessions. The presentations described current and future field testing plans, interpretation of field test data, environmental research, laboratory studies, modeling, and economics. All papers were processed for inclusion in the Energy Data Base.

  6. Biological production of ethanol from coal


    Due to the abundant supply of coal in the United States, significant research efforts have occurred over the past 15 years concerning the conversion of coal to liquid fuels. Researchers at the University of Arkansas have concentrated on a biological approach to coal liquefaction, starting with coal-derived synthesis gas as the raw material. Synthesis gas, a mixture of CO, H[sub 2], CO[sub 2], CH[sub 4] and sulfur gases, is first produced using traditional gasification techniques. The CO, CO[sub 2] and H[sub 2] are then converted to ethanol using a bacterial culture of Clostridium 1jungdahlii. Ethanol is the desired product if the resultant product stream is to be used as a liquid fuel. However, under normal operating conditions, the wild strain'' produces acetate in favor of ethanol in conjunction with growth in a 20:1 molar ratio. Research was performed to determine the conditions necessary to maximize not only the ratio of ethanol to acetate, but also to maximize the concentration of ethanol resulting in the product stream.

  7. Recent regulatory experience of low-Btu coal gasification. Volume III. Supporting case studies

    Ackerman, E.; Hart, D.; Lethi, M.; Park, W.; Rifkin, S.


    The MITRE Corporation conducted a five-month study for the Office of Resource Applications in the Department of Energy on the regulatory requirements of low-Btu coal gasification. During this study, MITRE interviewed representatives of five current low-Btu coal gasification projects and regulatory agencies in five states. From these interviews, MITRE has sought the experience of current low-Btu coal gasification users in order to recommend actions to improve the regulatory process. This report is the third of three volumes. It contains the results of interviews conducted for each of the case studies. Volume 1 of the report contains the analysis of the case studies and recommendations to potential industrial users of low-Btu coal gasification. Volume 2 contains recommendations to regulatory agencies.

  8. Applied research and evaluation of process concepts for liquefaction and gasification of western coals. Final report

    Wiser, W. H.


    Fourteen sections, including five subsections, of the final report covering work done between June 1, 1975 to July 31, 1980 on research programs in coal gasification and liquefaction have been entered individually into EDB and ERA. (LTN)

  9. Synergistic evaluation of the biomass/coal blends for co-gasification purposes

    S Gaqa, S Mamphweli, D Katwire, E Meyer


    Full Text Available Approximately 95% of electricity in South Africa is generated from coal, which is a fossil fuel that has detrimental environmental impacts. Eskom has started investigating the possibility of co-firing coal with biomass to improve their carbon footprint. However, co-firing utilizes approximately 80% of water and results in extensive environmental impacts. This research seeks to investigate the possibility of co-gasification of coal and biomass, which is a thermochemical process that uses about a third of the water required by a coal-fired power station, and results in much lower emissions. Thermogravimetric analysis (TGA was conducted to investigate the existence of a synergy between coal and biomass during gasification. Various coal/biomass blends were investigated using TGA. The synergistic effect between the two feedstock as determined through TGA allowed the prediction of the gasification characteristics of the blends that most likely gave the highest conversion efficiency. Preliminary results suggested the existence of this synergy.

  10. Technical analysis of advanced wastewater-treatment systems for coal-gasification plants


    This analysis of advanced wastewater treatment systems for coal gasification plants highlights the three coal gasification demonstration plants proposed by the US Department of Energy: The Memphis Light, Gas and Water Division Industrial Fuel Gas Demonstration Plant, the Illinois Coal Gasification Group Pipeline Gas Demonstration Plant, and the CONOCO Pipeline Gas Demonstration Plant. Technical risks exist for coal gasification wastewater treatment systems, in general, and for the three DOE demonstration plants (as designed), in particular, because of key data gaps. The quantities and compositions of coal gasification wastewaters are not well known; the treatability of coal gasification wastewaters by various technologies has not been adequately studied; the dynamic interactions of sequential wastewater treatment processes and upstream wastewater sources has not been tested at demonstration scale. This report identifies key data gaps and recommends that demonstration-size and commercial-size plants be used for coal gasification wastewater treatment data base development. While certain advanced treatment technologies can benefit from additional bench-scale studies, bench-scale and pilot plant scale operations are not representative of commercial-size facility operation. It is recommended that coal gasification demonstration plants, and other commercial-size facilities that generate similar wastewaters, be used to test advanced wastewater treatment technologies during operation by using sidestreams or collected wastewater samples in addition to the plant's own primary treatment system. Advanced wastewater treatment processes are needed to degrade refractory organics and to concentrate and remove dissolved solids to allow for wastewater reuse. Further study of reverse osmosis, evaporation, electrodialysis, ozonation, activated carbon, and ultrafiltration should take place at bench-scale.

  11. Biomass/coal steam co-gasification integrated with in-situ CO2 capture

    Addressing recent environmental regulations on fossil fuel power systems and both biomass fuel supply and coal greenhouse gas issues, biomass/coal co-gasification could provide a feasible transition solution for power plants. In the quest for an even more sustainable process, steam co-gasification of switchgrass and coal was integrated with in-situ CO2 capture, with limestone as the bed material and sorbent. Five gasification/carbonation (at <700 °C) and calcination (at >850 °C) cycles were performed in an atmospheric pilot scale bubbling fluidized bed reactor. Hydrogen production was enhanced significantly (∼22%) due to partial adsorption of CO2 by the CaO sorbent, shifting the gasification reactions forward, consistent with Le Châtelier's principle. Tar yield measurements showed that reducing the gasification temperature could be achieved without experiencing higher tar yield, indicating that the lime has a catalytic effect. The sorbent particles decayed and lost their calcium utilization efficiency in the course of cycling due to sintering. The co-existence of three types of solids (biomass, coal, lime) with different particle properties led to bed segregation. An equilibrium model was found to be useful in design of lime-enhanced gasification systems. - Highlights: • Biomass/coal steam co-gasification was integrated with in-situ CO2 capture. • 5 gasification/carbonation (<700 °C) and calcination (>850 °C) cycles were performed. • Lime-enhanced co-gasification enhanced hydrogen production significantly (∼22%). • CaO decayed as an absorbent of CO2 due to sintering and some was lost by attrition. • Equilibrium models are useful in design of lime-enhanced gasification systems

  12. Chemical looping coal gasification with calcium ferrite and barium ferrite via solid--solid reactions

    Siriwardane, Ranjani [U.S. Department of Energy/NETL; Riley, Jarrett [Oak Ridge Inst. for Science and Education (ORISE), Oak Ridge, TN (United States); Tian, Hanjing [West Virginia Univ., Morgantown, WV (United States); Richards, George [U.S. Department of Energy/NETL


    Coal gasification to produce synthesis gas by chemical looping was investigated with two oxygen carriers, barium ferrite (BaFe2O4) and calcium ferrite (CaFe2O4). Thermo-gravimetric analysis (TGA) and fixed-bed flow reactor data indicated that a solid–solid interaction occurred between oxygen carriers and coal to produce synthesis gas. Both thermodynamic analysis and experimental data indicated that BaFe2O4 and CaFe2O4 have high reactivity with coal but have a low reactivity with synthesis gas, which makes them very attractive for the coal gasification process. Adding steam increased the production of hydrogen (H2) and carbon monoxide (CO), but carbon dioxide (CO2) remained low because these oxygen carriers have minimal reactivity with H2 and CO. Therefore, the combined steam–oxygen carrier produced the highest quantity of synthesis gas. It appeared that neither the water–gas shift reaction nor the water splitting reaction promoted additional H2 formation with the oxygen carriers when steam was present. Wyodak coal, which is a sub-bituminous coal, had the best gasification yield with oxygen carrier–steam while Illinois #6 coal had the lowest. The rate of gasification and selectivity for synthesis gas production was significantly higher when these oxygen carriers were present during steam gasification of coal. The rates and synthesis gas yields during the temperature ramps of coal–steam with oxygen carriers were better than with gaseous oxygen.

  13. Preliminary study on co-gasification behavior of deoiled asphalt with coal and biomass

    Highlights: • Co-gasification of DOA with coal and biomass are proposed and studied. • Pure DOA char shows low reactivity mainly for low surface area, high graphitization degree and low ash content. • Co-gasification of coal and DOA does not show synergetic effect. • Synergetic effect between biomass and DOA is observed. • Potassium naturally in biomass can transfer to DOA and catalyzes the gasification of DOA. - Abstract: The co-gasification behavior of deoiled asphalt (DOA) with coal and biomass were investigated by a thermogravimetric analyzer (TGA). The gasification experiments were conducted under CO2 atmosphere within an isothermal temperature range from 900 to 1100 °C. The physical properties of the samples were examined by X-ray diffraction (XRD), scanning electron microscopy–energy dispersive spectroscopy (SEM–EDS), N2 and CO2 adsorption and inductively coupled plasma-atomic emission spectrometry (ICP-AES). Compared with coal or biomass, the low surface area, high graphitization degree and the low ash content are the main reasons for the low reactivity of DOA. The co-gasification of coal and DOA does not show synergetic effect, while the combination of biomass and DOA shows higher gasification reactivity than that of being calculated. The synergetic effect is mainly caused by the alkali metals. Further study shows the transfer of the potassium from the surface of biomass to DOA greatly increases the active sites of the DOA, which leads to obvious improvement of the co-gasification reactions. Meanwhile, the gasification experiments of adding coal and biomass ashes to DOA also support the above explanations

  14. Gasification Coupled Chemical Looping Combustion of Coal: A Thermodynamic Process Design Study

    Sonali A. Borkhade; Shriwas, Preksha A.; Ganesh R. Kale


    A thermodynamic investigation of gasification coupled chemical looping combustion (CLC) of carbon (coal) is presented in this paper. Both steam and CO2 are used for gasification within the temperature range of 500–1200°C. Chemical equilibrium model was considered for the gasifier and CLC fuel reactor. The trends in product compositions and energy requirements of the gasifier, fuel reactor, and air reactor were determined. Coal (carbon) gasification using 1.5 mol H2O and 1.5 mol CO2 per mole c...

  15. Underground Coal Gasification and CO2 Storage Support Bulgaria's Low Carbon Energy Supply

    Natalie Christine Nakaten; P. Kötting; R. Azzam; Thomas Kempka


    Underground coal gasification facilitates the utilization of deep-seated coals that are economically not exploitable via conventional mining. This study examines UCG as an approach for coal conversion into a synthesis gas as substitute for natural gas or to fuel a combined cycle gas turbine with CO2 capture and storage. Modelling results show that implementing UCG-CCS into the Bulgarian energy system depicts a low carbon alternative to coal fired power generation and can potentially decrease ...

  16. 煤气化废水中氰化物脱除技术研究进展%Research Progress of Cyanide Removal Technology From Coal Gasification Wastewater

    郭志华; 高会杰


    Gasification is a key technology in clean utilization of coal. Coal gasification wastewater contains various pollutants, such as ammonia nitrogen, COD, phenol and cyanide, among which cyanide is a highly toxic poison; it has strong corrosive effect on equipments and adverse impact on biochemical treatment of coal gasification wastewater. Oxidation, pyrohydrolysis, membrane and biological methods are common treatment methods of cyanide in coal gasification wastewater. In this article, research progress of the technologies for removing cyanide from coal gasification water was reviewed in detail.%煤气化工艺是煤的清洁化利用的关键技术之一。煤气化产生的废水中含有氨氮、COD、苯酚和氰化物等多种污染物,其中所含氰化物有剧毒,对设备有较强的腐蚀作用,且对生化处理煤气化废水产生不利的影响。常用的处理煤气化废水中氰化物的方法有氧化法、高温水解法、膜法及生物法。本文就煤气化废水中氰化物的脱除技术相关的研究进展进行了详细的介绍。

  17. Use of nuclear process heat for methane and hydrogen production via in-situ coal gasification

    Coal gasification plants and processes have been in existence for many years, using fossil fuel as the source of energy input. However, there appear to be no significant installations carrying out in-situ coal gasification and using high-temperature, high pressure, process heat (e.g., as steam) from a high-temperature nuclear reactor. In the present paper, historical and theoretical aspects of gasification are outlined and a concept is put forward for a full-scale commercial in-situ coal gasification plant using process steam from a high-temperature gas-cooled nuclear reactor, and producing two streams, one being methane for transport use and industrial feedstock, and the other being hydrogen for a future hydrogen economy. The possibility of a CANDU reactor meeting the thermal requirements is discussed

  18. Co-Gasification of Coal and Biomass in an IGCC Power Plant: Gasifier Modeling

    Luis Correas


    Full Text Available Co-gasification of coal and biomass in an existing coal-fired IGCC power plant is proposed as an efficient, flexible and environmentally friendly way to increase the biomass contribution to electricity generation. A model of an entrained flow gasifier is described and validated with nearly 3,000 actual steady-state operational data points (4,800 hours. The model is then used to study co-gasification of coal, petroleum coke and up to 10 percent of several types of biomass. As a result, the influence of fuel variations on gasifier performance and modifications in operation that should be made in co-gasification are obtained. A conclusion of our study is that co-gasification is possible provided that operation is properly adapted. A validated model can be very useful for predicting operating points for new fuel mixtures.

  19. ASPEN Plus simulation of coal integrated gasification combined blast furnace slag waste heat recovery system

    Highlights: • An integrated system of coal gasification with slag waste heat recovery was proposed. • The goal of BF slag heat saving and emission reduction was achieved by this system. • The optimal parameters were obtained and the waste heat recovery rate reached 83.08%. • About 6.64 kmol/min syngas was produced when using one ton BF slag to provide energy. - Abstract: This article presented a model for the system of coal gasification with steam and blast furnace slag waste heat recovery by using the ASPEN Plus as the simulating and modeling tool. Constrained by mass and energy balance for the entire system, the model included the gasifier used to product syngas at the chemical equilibrium based on the Gibbs free energy minimization approach and the boiler used to recover the heat of the blast furnace slag (BF slag) and syngas. Two parameters of temperature and steam to coal ratio (S/C) were considered to account for their impacts on the Datong coal (DT coal) gasification process. The carbon gasification efficiency (CE), cold gasification efficiency (CGE), syngas product efficiency (PE) and the heating value of syngas produced by 1 kg pulverized coal (HV) were adopted as the indicators to examine the gasification performance. The optimal operating temperature and S/C were 800 °C and 1.5, respectively. At this condition, CE reached above 90% and the maximum values of the CGE, PE and HV were all obtained. Under the optimal operating conditions, 1000 kg/min BF slag, about 40.41 kg/min DT pulverized coal and 77.94 kg/min steam were fed into the gasifier and approximate 6.64 kmol/min syngas could be generated. Overall, the coal was converted to clean syngas by gasification reaction and the BF slag waste heat was also recovered effectively (reached up to 83.08%) in this system, achieving the objective of energy saving and emission reduction

  20. Numerical simulations and correlations on the coal -conveying gas flow in pipe for fluidized -bed coal gasification facility

    CFD modeling and simulation are made on the key flow elements, vertical, horizontal pipes and elbow pipes , used in the pneumatic coal -transport system of fluidized -bed gasification test facility. The coal- gas flow inside the flow elements are modeled by combining Reynolds -stress Averaged Navier- Stokes equations Solver (RANS), k- ε turbulence model and Discrete Phase Model (DPM) in the ANSYS Fluent code. Using the developed coal -gas flow analysis model, computations are carried out to investigate the gas flow path, the coal particle behavior and the pressure loss characteristics in flow element at various coal/ gas loading ratio and coal mass flux. The present prediction results show the coal -gas flow behavior of each flow element is changed from dilute -flow to dense -flow pattern at a specific coal/gas loading ratio where pressure loss is abruptly increased. From the numerical results, the present study also provides the limiting coal/gas loading conditions to secure stable coal feeding and the correlations for pressure losses in horizontal, vertical and elbow pipes, which can be suitable for the design guidelines of actual fluidized -bed coal gasification. Key words : Pneumatic Coal -Transport; Coal -Gas Flow, Dense Phase Flow; Dilute Phase Flow; Pressure Loss; Coal/Gas Loading Ratio; Correlation

  1. A new model to estimate CO2 coal gasification kinetics based only on parent coal characterization properties

    Highlights: • A mathematical model to predict gasification rate and residence time was proposed. • Gasification rate is affected mainly by micropore surface area and alkaline content. • Residence time for coal gasification can be predicted without a kinetic model. • Surface area based on carbon content is an important parameter in kinetic analysis. • The model can predict the kinetic of coal blends in any ash composition range. - Abstract: A new mathematical model is proposed for the estimation of CO2 gasification kinetics of different rank coals and ash contents. There are no previous reports on the determination of the conversion rate or even residence time of CO2 or steam gasification based on coal characterization and for a wide range of ash content. This new approach can be used to infer the residence time and other parameters required for reactor design and operation optimization of newly mined coals or coal mixtures used as feedstock. The coal micropore surface area and the alkaline content determined by the ash composition were proved to be the most significant variables influencing the gasification rate. These variables were correlated to formulate a semi-empirical expression based on the Arrhenius equation. An equation to infer residence time, independent of the kinetic model, is also presented. The new equation is important in understanding the catalytic effect of the alkaline content in the temperature range where the chemical reaction is the controlling step. It can also be used as the corresponding term of the chemical reaction in a gas–solid kinetic model when working at higher temperatures. This new approach is valid, if there is not loss of alkali and alkaline earth metals due to sublimation or melting, which results in a glassy slag structure. The proposed model has direct industrial application in simulation of gasifiers’ performance with the knowledge of only coal characterization properties

  2. Fundamental research on novel process alternatives for coal gasification: Final report

    Hill, A H; Knight, R A; Anderson, G L; Feldkirchner, H L; Babu, S P


    The Institute of Gas Technology has conducted a fundamental research program to determine the technical feasibility of and to prepare preliminary process evaluations for two new approaches to coal gasification. These two concepts were assessed under two major project tasks: Task 1. CO/sub 2/-Coal Gasification Process Concept; Task 2. Internal Recirculation Catalysts Coal Gasification Process Concept. The first process concept involves CO/sub 2/-O/sub 2/ gasification of coal followed by CO/sub 2/ removal from the hot product gas by a solid MgO-containing sorbent. The sorbent is regenerated by either a thermal- or a pressure-swing step and the CO/sub 2/ released is recycled back to the gasifier. The product is a medium-Btu gas. The second process concept involves the use of novel ''semivolatile'' materials as internal recirculating catalysts for coal gasification. These materials remain in the gasifier because their vapor pressure-temperature behavior is such that they will be in the vapor state at the hotter, char exit part of the reactor and will condense in the colder, coal-inlet part of the reactor. 21 refs., 43 figs., 43 tabs.

  3. Coal gasification systems engineering and analysis. Appendix G: Commercial design and technology evaluation


    A technology evaluation of five coal gasifier systems (Koppers-Totzek, Texaco, Babcock and Wilcox, Lurgi and BGC/Lurgi) and procedures and criteria for evaluating competitive commercial coal gasification designs is presented. The technology evaluation is based upon the plant designs and cost estimates developed by the BDM-Mittelhauser team.

  4. 3rd international conference on coal gasification and liquefaction, University of Pittsburgh



    The third annual international conference on ''Coal Gasification and Liquefaction: What Needs to be Done Now'' was held at the University of Pittsburgh, Pittsburgh, PA on August 3-5, 1976. The majority of the papers dealt with coal gasification and liquefaction (often on the basis of process pilot plant experience) and on flue gas desulfurization by a variety of processes; fewer papers involved fluidized bed combustion, combined cycle power plants, coal desulfurization, government policy on environmental effects and on synthetic fuels, etc. Twenty-eight papers have been entered individually into EDB and ERA. (LTN)

  5. Catalytic mechanism of sodium compounds in black liquor during gasification of coal black liquor slurry

    The coal black liquor slurry (CBLS) was composed of coal and black pulping liquor, which has plenty of sodium compounds, lignin and cellulose. The sodium compounds have a catalytic effect on the gasification process of coal black liquor slurry, while lignin and cellulose enhance the heat value. Alkali-catalyzed gasification experiments of CBLS and CWS (coal water slurry) are investigated on the thermobalance and fixed bed reactor. The residues of the gasification of CBLS and CWS are analyzed by XRD, SEM and FT-IR. It is found that many micro- and mesopores and zigzag faces exist in the surface of the CBLS coke, which play a key role in the catalytic gasification. Sodium can enhance the reaction potential, weaken the bond of C-O and improve the gasification reaction rate. XRD results show that sodium aluminum silicate and nepheline are the main crystal components of the CBLS and CWS. The C-O stretching vibration peak in the 1060 cm-1 band in the CBLS shifts to 995.65 cm-1 in the CBLS coke after partial gasification. This means that the energy of the C-O stretching vibration in the CBLS carbon matrix decreases, so the structure of the carbon matrix is more liable to react with an oxygen ion or hydroxide ion. The amplitude of the C-O stretching vibration peak is augmented step by step due to the ground-excited level jump of the C-O band

  6. Presence of an unusual methanogenic bacterium in coal gasification waste

    Tomei, F.A.; Rouse, D.; Maki, J.S.; Mitchell, R.


    Methanogenic bacteria growing on a pilot-scale, anaerobic filter processing coal gasification waste were enriched in a mineral salts medium containing hydrogen and acetate as potential energy sources. Transfer of the enrichments to methanol medium resulted in the initial growth of a strain of Methanosarcina barkeri, but eventually small cocci became dominant. The cocci growing on methanol produced methane and exhibited the typical fluorescence of methanogenic bacteria. They grew in the presence of the cell wall synthesis-inhibiting antibiotics D-cycloserine, fosfomycin, penicillin G, and vancomycin as well as in the presence of kanamycin, an inhibitor of protein synthesis in eubacteria. The optimal growth temperature was 37 degrees C, and the doubling time was 7.5 h. The strain lysed after reaching stationary phase. The bacterium grew poorly with hydrogen as the energy source and failed to grow on acetate. Morphologically, the coccus shared similarities with Methanosarcina sp. Cells were 1 wide, exhibited the typical thick cell wall and cross-wall formation, and formed tetrads. Packets and cysts were not formed. 62 refs., 4 figs.

  7. Coal-gasification/MHD/steam-turbine combined-cycle (GMS) power generation

    Lytle, J.M.; Marchant, D.D.


    The coal-gasification/MHD/steam-turbine combined cycle (GMS) refers to magnetohydrodynamic (MHD) systems in which coal gasification is used to supply a clean fuel (free of mineral matter and sulfur) for combustion in an MHD electrical power plant. Advantages of a clean-fuel system include the elimination of mineral matter or slag from all components other than the coal gasifier and gas cleanup system; reduced wear and corrosion on components; and increased seed recovery resulting from reduced exposure of seed to mineral matter or slag. Efficiencies in some specific GMS power plants are shown to be higher than for a comparably sized coal-burning MHD power plant. The use of energy from the MHD exhaust gas to gasify coal (rather than the typical approach of burning part of the coal) results in these higher efficiencies.


    The integrated-gasification combined-cycle (IGCC) process is an emerging technology that utilizes coal for power generation and production of chemical feedstocks. However, the process generates large amounts of solid waste, consisting of vitrified ash (slag) and some unconverted carbon. In previous projects, Praxis investigated the utilization of ''as-generated'' slags for a wide variety of applications in road construction, cement and concrete production, agricultural applications, and as a landfill material. From these studies, we found that it would be extremely difficult for ''as-generated'' slag to find large-scale acceptance in the marketplace even at no cost because the materials it could replace were abundantly available at very low cost. It was further determined that the unconverted carbon, or char, in the slag is detrimental to its utilization as sand or fine aggregate. It became apparent that a more promising approach would be to develop a variety of value-added products from slag that meet specific industry requirements. This approach was made feasible by the discovery that slag undergoes expansion and forms a lightweight material when subjected to controlled heating in a kiln at temperatures between 1400 and 1700 F. These results confirmed the potential for using expanded slag as a substitute for conventional lightweight aggregates (LWA). The technology to produce lightweight and ultra-lightweight aggregates (ULWA) from slag was subsequently developed by Praxis with funding from the Electric Power Research Institute (EPRI), Illinois Clean Coal Institute (ICCI), and internal resources. The major objectives of the subject project are to demonstrate the technical and economic viability of commercial production of LWA and ULWA from slag and to test the suitability of these aggregates for various applications. The project goals are to be accomplished in two phases: Phase I, comprising the production of LWA and ULWA from slag at the large pilot scale, and

  9. Japan`s New Sunshine Project. 20. 1995 annual summary of coal liquefaction and gasification



    The paper described a summary of the 1995 study on coal liquefaction and gasification under the New Sunshine Project. As for coal liquefaction, a study was made of liquefaction characteristics and catalysts of various coals. Also studied were liquefaction conditions for quality improvement of liquefaction products, an evaluation method of quality of coal liquid, and a utilization method of coal liquid. In order to prevent carbonization and realize effective liquefaction, a study was conducted for elucidation of the reaction mechanism of high pressure hydrogenation. In a 150t/d pilot plant using hydrogen transfer hydrogenation solvents, the NEDOL method was studied using various catalysts and kinds of coals. This is a step prior to data acquisition for engineering, actual construction of equipment and operation. A 1t/d process supporting unit is a unit to support it. The unit conducts studies on slurry letdown valves and synthetic iron sulfide catalysts, screening of Chinese coals, etc. As to coal gasification, the paper added to the basic research the combined cycle power generation using entrained flow coal gasification for improvement of thermal efficiency and environmental acceptability and the HYCOL method for hydrogen production. 68 refs., 40 figs.

  10. Fluidized-Bed Gasification of Plastic Waste, Wood, and Their Blends with Coal

    Lucio Zaccariello


    Full Text Available The effect of fuel composition on gasification process performance was investigated by performing mass and energy balances on a pre-pilot scale bubbling fluidized bed reactor fed with mixtures of plastic waste, wood, and coal. The fuels containing plastic waste produced less H2, CO, and CO2 and more light hydrocarbons than the fuels including biomass. The lower heating value (LHV progressively increased from 5.1 to 7.9 MJ/Nm3 when the plastic waste fraction was moved from 0% to 100%. Higher carbonaceous fines production was associated with the fuel containing a large fraction of coal (60%, producing 87.5 g/kgFuel compared to only 1.0 g/kgFuel obtained during the gasification test with just plastic waste. Conversely, plastic waste gasification produced the highest tar yield, 161.9 g/kgFuel, while woody biomass generated only 13.4 g/kgFuel. Wood gasification showed a carbon conversion efficiency (CCE of 0.93, while the tests with two fuels containing coal showed lowest CCE values (0.78 and 0.70, respectively. Plastic waste and wood gasification presented similar cold gas efficiency (CGE values (0.75 and 0.76, respectively, while that obtained during the co-gasification tests varied from 0.53 to 0.73.

  11. Laboratory studies on cavity growth and product gas composition in the context of underground coal gasification

    Systematic laboratory scale experiments on coal blocks can provide significant insight into the underground coal gasification (UCG) process. Our earlier work has demonstrated the various features of the early UCG cavity shape and rate of growth through lab-scale experiments on coal combustion, wherein the feed gas is oxygen. In this paper, we study the feasibility of in situ gasification of coal in a similar laboratory scale reactor set-up, under conditions relevant for field practice of UCG, using an oxygen-steam mixture as the feed gas. By performing the gasification reaction in a cyclic manner, we have been able to obtain a product gas with hydrogen concentrations as high as 39% and a calorific value of 178 kJ/mol. The effect of various operating parameters such as feed temperature, feed steam to oxygen ratio, initial combustion time and so on, on the product gas composition is studied and the optimum operating conditions in order to achieve desired conversion to syngas, are determined. We also study the effect of various design and operating parameters on the evolution of the gasification cavity. Empirical correlations are proposed for the change in cavity volume and its dimensions in various directions. The results of the previous study on the combustion cavity evolution are compared with this gasification study. -- Research highlights: →Proposed a systematic methodology to mimic the UCG process in the lab-scale. →Identified possible factors that influence thermo-mechanical spalling of coal. →Proposed optimum operating conditions in order to obtain maximum gasification yield. →Captured the shape of cavity and its growth in all directions. →Compared combustion cavity growth with that of gasification.

  12. LLNL Underground-Coal-Gasification Project. Quarterly progress report, July-September 1981

    Stephens, D.R.; Clements, W. (eds.)


    We have continued our laboratory studies of forward gasification in small blocks of coal mounted in 55-gal drums. A steam/oxygen mixture is fed into a small hole drilled longitudinally through the center of the block, the coal is ignited near the inlet and burns toward the outlet, and the product gases come off at the outlet. Various diagnostic measurements are made during the course of the burn, and afterward the coal block is split open so that the cavity can be examined. Development work continues on our mathematical model for the small coal block experiments. Preparations for the large block experiments at a coal outcrop in the Tono Basin of Washington State have required steadily increasing effort with the approach of the scheduled starting time for the experiments (Fall 1981). Also in preparation is the deep gasification experiment, Tono 1, planned for another site in the Tono Basin after the large block experiments have been completed. Wrap-up work continues on our previous gasification experiments in Wyoming. Results of the postburn core-drilling program Hoe Creek 3 are presented here. Since 1976 the Soviets have been granted four US patents on various aspects of the underground coal gasification process. These patents are described here, and techniques of special interest are noted. Finally, we include ten abstracts of pertinent LLNL reports and papers completed during the quarter.

  13. Novel fragmentation model for pulverized coal particles gasification in low temperature air thermal plasma

    Jovanović Rastko D.


    Full Text Available New system for start-up and flame support based on coal gasification by low temperature air thermal plasma is planned to supplement current heavy oil system in Serbian thermal power plants in order to decrease air pollutions emission and operational costs. Locally introduced plasma thermal energy heats up and ignites entrained coal particles, thus starting chain process which releases heat energy from gasified coal particles inside burner channel. Important stages during particle combustion, such as particle devolatilisation and char combustion, are described with satisfying accuracy in existing commercial CFD codes that are extensively used as powerful tool for pulverized coal combustion and gasification modeling. However, during plasma coal gasification, high plasma temperature induces strong thermal stresses inside interacting coal particles. These stresses lead to “thermal shock” and extensive particle fragmentation during which coal particles with initial size of 50-100 m disintegrate into fragments of at most 5-10 m. This intensifies volatile release by a factor 3-4 and substantially accelerates the oxidation of combustible matter. Particle fragmentation, due to its small size and thus limited influence on combustion process is commonly neglected in modelling. The main focus of this work is to suggest novel approach to pulverized coal gasification under high temperature conditions and to implement it into commercial comprehensive code ANSYS FLUENT 14.0. Proposed model was validated against experimental data obtained in newly built pilot scale D.C plasma burner test facility. Newly developed model showed very good agreement with experimental results with relative error less than 10%, while the standard built-in gasification model had error up to 25%.

  14. Hoe Creek II field experiment on underground coal gasification, preliminary results

    Aiman, W.R.; Thorsness, C.B.; Hill, R.W.; Rozsa, R.B.; Cena, R.; Gregg, D.W.; Stephens, D.R.


    A second in-situ coal gasification experiment was performed by Lawrence Livermore Laboratory at Hoe Creek in Wyoming. The Linked Vertical Wells scheme for in-situ coal gasification was used. The experiment took 100 days for air flow testing, reverse combustion linking, forward combustion gasification, and post-burn steam flow. Air was used for gasification except for a 2-day test with oxygen and steam. Reverse combustion linking took 14 days at 1.6 m/day. Air requirements for linking were 0.398 Mgmol per meter of link assuming a single direct link. The coal pyrolysed during linking was 17 m/sup 3/, which corresponds to a single link 1.0 m in diameter. There was, however, strong evidence of at least two linkage paths. The detected links stayed below the 3 m level in the 7.6 coal seam; however, the product flow from the forward-burn gasification probably followed the coal-overburden interface not the reverse burn channels at the 3 m level. A total of 232 Mgmols (194 Mscf) of gas was produced with heating value above 125 kJ/mol (140 Btu/scf) for significant time periods and an average of 96 kJ/mol (108 Btu/scf). During the oxygen-steam test the heating value was above 270 kJ/gmol (300 Btu/scf) twice and averaged 235 kJ/gmol (265 Btu/scf). The coal recovery was 1310 m/sup 3/ (1950 ton). Gasification was terminated because of decreasing product quality not because of burn through. The product quality decreased because of increasing underground heat loss.

  15. The calculation of gasification from coal in a fixed bed reactor

    Hoersgen, B.; Koehne, H.


    A one dimension, two phase model for the transfer of coal into gas through the Lurgi pressure gasification process is discussed. Calculations for drying, devolatilization, and gasification are presented along with energy and mass transport operations. The heterogeneous chemical reactions of carbon with hydrogen, water vapor, and carbon dioxide, and the homogeneous reaction between carbon monoxide and water vapor are described by kinetic equations, that take into account deviations from thermodynamic equilibrium as the driving potential of the chemical reaction. Data from different types of coal and different gas compositions were used to test the model.

  16. Geochemistry of ultra-fine and nano-compounds in coal gasification ashes: A synoptic view

    Kronbauer, Marcio A. [Centro Universitário La Salle, Mestrado em Avaliação de Impactos Ambientais em Mineração, Victor Barreto, 2288 Centro, 92010-000 Canoas, RS (Brazil); Universidade Federal do Rio Grande do Sul, Escola de Engenharia, Departamento de Metalurgia, Centro de Tecnologia, Av. Bento Gonçalves, 9500, Bairro Agronomia, CEP: 91501-970, Porto Alegre, RS (Brazil); Izquierdo, Maria [School of Applied Sciences, Cranfield University, Bedfordshire MK43 0AL (United Kingdom); Dai, Shifeng [State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Beijing 100083 (China); Waanders, Frans B. [School of Chemical and Minerals Engineering, North West University (Potchefstroom campus), Potchefstroom 2531 (South Africa); Wagner, Nicola J. [School of Chemical and Metallurgical Engineering, University of the Witwatersrand, Johannesburg (South Africa); Mastalerz, Maria [Indiana Geological Survey, Indiana University, Bloomington, IN 47405-2208 (United States); Hower, James C. [University of Kentucky Center for Applied Energy Research, 2540 Research Park Drive, Lexington, KY 40511 (United States); Oliveira, Marcos L.S. [Environmental Science and Nanotechnology Department, Catarinense Institute of Environmental Research and Human Development, IPADHC, Capivari de Baixo, Santa Catarina (Brazil); Taffarel, Silvio R.; Bizani, Delmar [Centro Universitário La Salle, Mestrado em Avaliação de Impactos Ambientais em Mineração, Victor Barreto, 2288 Centro, 92010-000 Canoas, RS (Brazil); and others


    The nano-mineralogy, petrology, and chemistry of coal gasification products have not been studied as extensively as the products of the more widely used pulverized-coal combustion. The solid residues from the gasification of a low- to medium-sulfur, inertinite-rich, volatile A bituminous coal, and a high sulfur, vitrinite-rich, volatile C bituminous coal were investigated. Multifaceted chemical characterization by XRD, Raman spectroscopy, petrology, FE-SEM/EDS, and HR-TEM/SEAD/FFT/EDS provided an in-depth understanding of coal gasification ash-forming processes. The petrology of the residues generally reflected the rank and maceral composition of the feed coals, with the higher rank, high-inertinite coal having anisotropic carbons and inertinite in the residue, and the lower rank coal-derived residue containing isotropic carbons. The feed coal chemistry determines the mineralogy of the non-glass, non-carbon portions of the residues, with the proportions of CaCO{sub 3} versus Al{sub 2}O{sub 3} determining the tendency towards the neoformation of anorthite versus mullite, respectively. Electron beam studies showed the presence of a number of potentially hazardous elements in nanoparticles. Some of the neoformed ultra-fine/nano-minerals found in the coal ashes are the same as those commonly associated with oxidation/transformation of sulfides and sulfates. - Highlights: • Coal waste geochemisty can provide increased environmental information in coal-mining areas. • Oxidation is the major process for mineral transformation in coal ashes. • The electron bean methodology has been applied to investigate neoformed minerals.

  17. Coal conversion processes and analysis methodologies for synthetic fuels production. [technology assessment and economic analysis of reactor design for coal gasification


    Information to identify viable coal gasification and utilization technologies is presented. Analysis capabilities required to support design and implementation of coal based synthetic fuels complexes are identified. The potential market in the Southeast United States for coal based synthetic fuels is investigated. A requirements analysis to identify the types of modeling and analysis capabilities required to conduct and monitor coal gasification project designs is discussed. Models and methodologies to satisfy these requirements are identified and evaluated, and recommendations are developed. Requirements for development of technology and data needed to improve gasification feasibility and economies are examined.

  18. The underground coal gasification First step of community collaboration; Gasification Subterranea del Carbon. Primer Intento en el Ambito de una Colaboracion Comunitaria



    The objective of the project was to demonstrate the technical feasibility of underground coal gasification in coal seams at 600 metre depth, in order to asses its potential as a means of energy exploitation in Europe. The trial was based on the use of deviated boreholes and a retractable injection system techniques, which have both been developed by the oil and gas industries. One borehole, the injection well, was drilled in the coal seam. The other, the vertical production well, was run to intercept it in the lower part of the coal seam as closely as possible, in order to construct a continuous channel for gasification. The well were completed with casing and concentric tubing to provide the necessary paths for production, injection, purging gas and cooling water flows. A coiled tubing located in the injection well was used to execute the retraction (or CRIP) manoeuvre, which is a process in which the injector head for the gasification agents, i. e. oxygen and water, and the ignitor, are directed to a specific section of the coal seam. The gasification products passes to a surface production line for flow measurement and sampling of gas and condensate products. Production gases were either flared or incinerated, while the liquids were collected for appropriate disposal. The first trial achieved its principal objectives of in seam drilling, channel communication, the CRIP manoeuvres and the gasification of significant quantity of coal. The post-gasification study also identified the shape and extent of the cavity. The study has demonstrated the technical feasibility of underground coal gasification at the intermediate depths of European coal and proposals are made for further development and semi-commercial exploitation of this promising extraction technology. (Author) 11 refs.

  19. Subtask 4.2 - Coal Gasification Short Course

    Kevin Galbreath


    Major utilities, independent power producers, and petroleum and chemical companies are intent on developing a fleet of gasification plants primarily because of high natural gas prices and the implementation of state carbon standards, with federal standards looming. Currently, many projects are being proposed to utilize gasification technologies to produce a synthesis gas or fuel gas stream for the production of hydrogen, liquid fuels, chemicals, and electricity. Financing these projects is challenging because of the complexity, diverse nature of gasification technologies, and the risk associated with certain applications of the technology. The Energy & Environmental Research Center has developed a gasification short course that is designed to provide technical personnel with a broad understanding of gasification technologies and issues, thus mitigating the real or perceived risk associated with the technology. Based on a review of research literature, tutorial presentations, and Web sites on gasification, a short course presentation was prepared. The presentation, consisting of about 500 PowerPoint slides, provides at least 7 hours of instruction tailored to an audience's interests and needs. The initial short course is scheduled to be presented September 9 and 10, 2009, in Grand Forks, North Dakota.

  20. Program of the GEGN (study group for the gasification of coal by nuclear heat)

    Gaz de France has investigated the possibilities of producing a gas from coal and nuclear energy, to make up a natural gas supply by the end of the century and onwards. With this in view the GEGN (study group for the gasification of coal by nuclear heat) has been set up by gas de France, the Commissariat a l'Energie Atomique, Charbonnages de France, Creusot-Loire and Novatome. Its work is described here. The general principles of coal gasification are reviewed and the main options of the project adopted by the GEGN are discussed. This project covers two complementary fields which are examined in turn: nuclear steam reforming of methane, using a high-temperature nuclear reactor (study carried out by the CEA) and hydrogenation of liquefied coal, studied on a CHERCHAR trial bench and the conversion of the products obtained into gaseous products

  1. A comprehensive experimental procedure for CO2 coal gasification: Is there really a maximum reaction rate?

    Highlights: • The maximum reaction rate during gasification is caused by switching the gas. • The time to observe a maximum only depends on gas flow rate and reactor volume. • Isothermal pyrolysis step prior to gasification reduces char mesopore area. • An improved gasification procedure using TGA has been proposed and evaluated. • Results with the new procedure exhibit no maximum with faster reaction rate. - Abstract: A novel procedure to perform carbon dioxide (CO2) gasification studies was tested with two different Alberta coals and compared to the most common procedures using thermogravimetric analysis (TGA). The designed experiments indicate that maximum reaction rates reported in the literature were probably a consequence of the increasing CO2 concentration in the gas mixture when the inert gas was switched to CO2. It has been proven that, independent of feedstocks, the time to observe this maximum reaction rate was constant, indicating the reported maximum reaction rate depends only on the gas dispersion when the gasifying agent is fed and not on the surface properties of the char. In addition, the comparison of different experimental procedures shows the time that the char was exposed to an inert gas atmosphere prior to gasification, decreased the reactivity of the char. The reason is a reduction of the char mesopore area, which was induced when pyrolysis and gasification were separated with an isothermal step using an inert gas. The random pore model is the most common model used to describe coal and biomass gasification in the literature, since it can predict a maximum reaction rate for a determined conversion. However, its usage may be inappropriate for gasification kinetics analysis, if the changing gas mixture effect and the char surface area reduction induced by the experimental procedure are not considered

  2. Nuclear coal gasification - achieved state, evaluation and use of the results

    By the research and development programme for water steam gasification of coal, which was completed in 1984, it could be demonstrated and proved in long-term experiments on semitechnical test plants, that bakeable hard coal can be dosed by means of a jet charger, permanently gasified and that by the application of catalysts the gasification performance can be increased. The works were continuously supported by investigations in the laboratory and in process models. Among other things these included the gasification kinetics, the application of catalysts, the dwell time spread of the solid material in the fluidized bed, scale-up problems of the jet charger as well as investigations of the material contained in crude gas and waste water. (orig./DG)


    Ambient air samples were collected continuously from May 14-29, 1980 to determine if the emissions from a commercial Lurgi coal gasification plant could be identified downwind of the facility. Physical, inorganic, and organic analyses were carried out on the collected aerosol sam...


    The report discusses analytical information, obtained from Sasol I, on the emission and effluent streams analyzed in the normal course of operation and testing. The purpose was to provide EPA with representative information on a commercial-size Lurgi-based coal gasification proje...


    The report gives results of an investigation of two techniques (hydrocracking of heavy organics in the raw gas prior to quency, and wet oxidation of the gasifier condensate) for pollutant control in coal gasification processes. Bench-scale experiments were used to determine rates...

  6. Effect of Process Parameters on the Mass Transport Phenomena during Underground Coal Gasification

    Soukup, Karel; Stanczyk, K.; Rogut, J.; Schneider, Petr; Šolcová, Olga

    -: -, 2011, GP036. ISBN N. [International Conference GeoProc2011: Cross Boundaries Through THMC Integration /4./. Perth (AU), 06.07.2011-09.07.2011] Grant ostatní: RFCR(XE) CT-2011-00002 Institutional research plan: CEZ:AV0Z40720504 Keywords : underground coal gasification * texture characteristics * transport parameters Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  7. Underground coal gasification (citations from the NTIS Data Base). Report for 1964-1978

    Cavagnaro, D.


    Research reports on in-situ coal gasification are cited. Some of the techniques include rock fracturing, combustion, gas removal, economic, costs, and environmental factors. (This updated bibliography contains 235 abstracts, none of which are new entries to the previous edition.)

  8. Underground coal gasification (citations from the Engineering Index Data Base). Report for 1970-Apr 80

    Cavagnaro, D.M.


    The bibliography presents worldwide research pertaining to underground (in-situ) coal gasification. It includes environmental effects, the different processes and techniques that are used, gas removal, rock fracturing, costs, and economics. (This updated bibliography contains 269 abstracts, 106 of which are new entries to the previous edition.)

  9. Energetic analysis and optimisation of an integrated coal gasification-combined cycle power plant

    Vlaswinkel, E.E.


    Methods are presented to analyse and optimise the energetic performance of integrated coal gasification-combined cycle (IGCC) power plants. The methods involve exergy analysis and pinch technology and can be used to identify key process parameters and to generate alternative design options for impro

  10. Exergy Analysis of Methanol-IGCC Polygeneration Technology Based on Coal Gasification

    段远源; 张晋; 史琳; 朱明善; 韩礼钟


    Polygeneration is a key strategy for making ultra-clean energy products highly competitive with conventional energy systems. A polygeneration system based on coal gasification was analyzed using the exergy method to calculate the system thermal efficiency. The results show that the polygeneration system has less pollutants and higher efficiency than the separate systems.

  11. Production of hydrogen by direct gasification of coal with steam using nuclear heat


    Problems related to: (1) high helium outlet temperature of the reactor, and (2) gas generator design used in hydrogen production are studied. Special attention was given to the use of Oklahoma coal in the gasification process. Plant performance, operation, and environmental considerations are covered.

  12. Meditation on the construction of exemplar plant for briquetted coal gasification

    Zhou Kuiyi [China National Coal Industry Import and Export Corporation, Beijing (China)


    China uses a considerable amount of anthracite, but the fines from anthracite mining are not sufficiently used. This project involved the construction of a plant for the manufacture of anthracite briquettes under high pressure, for use in gasification plants. The characteristics of the coals used and the types of briquette formed are described. 2 tabs.

  13. Promoting effect of various biomass ashes on the steam gasification of low-rank coal

    Highlights: • Biomass ash was utilized to promote gasification of low rank coal. • Promoting effect of biomass ash highly depended on AAEM content in the ash. • Stability of the ash could be improved by maintaining AAEM amount in the ash. • Different biomass ash could have completely different catalytic activity. - Abstract: Application of biomass ash as a catalyst to improve gasification rate is a promising way for the effective utilization of waste ash as well as for the reduction of cost. Investigation on the catalytic activity of biomass ash to the gasification of low rank coal was performed in details in the present study. Ashes from 3 kinds of biomass, i.e. brown seaweed/BS, eel grass/EG, and rice straw/RS, were separately mixed with coal sample and gasified in a fixed bed downdraft reactor using steam as the gasifying agent. BS and EG ashes enhanced the gas production rate greater than RS ash. Higher catalytic activity of BS or EG ash was mainly attributed to the higher content of alkali and alkaline earth metal (AAEM) and lower content of silica in it. Higher content of silica in the RS ash was identified to have inhibiting effect for the steam gasification of coal. Stable catalytic activity was remained when the amount of AAEM in the regenerated ash was maintained as that of the original one

  14. Simulation of coal gasification in a pressurized spout-fluid bed gasifier

    Li, Q.J.; Zhang, M.Y.; Zhong, W.Q.; Wang, X.F.; Xiao, R.; Jin, B.S. [Nanjing Institute of Chemical Technology, Nanjing (China). Dept. of Environmental Engineering


    Based on an Eulerian-Eulerian method, a three-dimensional kinetic model involving mass transfer, momentum transfer, heat transfer, and chemical reaction is developed to simulate the process of coal gasification in a 2 MWth, pressurized spout-fluid bed of 450 mm in diameter with bed pressure up to 0.5 MPa. The effects of operating pressure and bed temperature on coal gasification are investigated. The high operating pressure is beneficial to coal gasification due to the fact that the fluidization in the reactor becomes better. On one hand, a higher bed temperature can accelerate the rate of reaction. On the other hand, more air will be taken in the gasifier to keep the higher bed temperature which will consume part of combustible gases produced by coal pyrolysis or gasification. Experimental verification was carried out in a 2 MWth, thermal input pressurized spout-fluid bed under the same operating condition. The comparison of calculation results with experimental results shows that most of the calculation errors are within the range of 15%.

  15. An evaluation of Substitute natural gas production from different coal gasification processes based on modeling

    Coal and lignite will play a significant role in the future energy production. However, the technical options for the reduction of CO2 emissions will define the extent of their share in the future energy mix. The production of synthetic or substitute natural gas (SNG) from solid fossil fuels seems to be a very attractive process: coal and lignite can be upgraded into a methane rich gas which can be transported and further used in high efficient power systems coupled with CO2 sequestration technologies. The aim of this paper is to present a modeling analysis comparison between substitute natural gas production from coal by means of allothermal steam gasification and autothermal oxygen gasification. In order to produce SNG from syngas several unit operations are required such as syngas cooling, cleaning, potential compression and, of course, methanation reactors. Finally the gas which is produced has to be conditioned i.e. removal of unwanted species, such as CO2 etc. The heat recovered from the overall process is utilized by a steam cycle, producing power. These processes were modeled with the computer software IPSEpro™. An energetic and exergetic analysis of the coal to SNG processes have been realized and compared. -- Highlights: ► The production of SNG from coal is examined. ► The components of the process were simulated for integrated autothermal or allothermal coal gasification to SNG. ► The energetic and exergetic evaluation of the two processes is presented.

  16. Steam gasification of coal, project prototype plant nuclear process heat: Report at the end of the reference phase

    Vanheek, K. H.


    The work carried out in the field of steam gasification of coal is described. On the basis of the status achieved to date, it can be stated that the mode of operation of the gas generator developed, including the direct feeding of caking high volatile coal, is technically feasible. Moreover, throughput can be improved by 65% at minimum by using catalysts. On the whole, industrial application of steam gasification, using nuclear process heat, stays attractive compared with other gasification processes. Not only coal is conserved, but also the costs of the gas manufactured are favorable. As confirmed by recent economic calculations, these are 20 to 25% lower.

  17. Agglomeration behaviour of high ash Indian coals in fluidized bed gasification pilot plant

    Although gasification of high ash Indian coals is gaining importance, the resultant uncertainties associated with agglomerate formation are still unresolved. To address this, a suitable pilot scale Fluidized Bed Gasifier was utilized in this study. Stabilized operating conditions in terms of coal feed rate, air feed rate, bed temperature, etc., already identified for maximum possible carbon conversion, were maintained in all experiments and the steam flow rate was only varied. Though the ash fusion temperature of the coals were above 1200 °C, agglomerate was formed during gasification at 950 °C with ‘steam to coal ratio’ less than 0.15 (kg/kg). On increasing this ratio above 0.2 local heat-concentration and agglomeration could be avoided with certainty. Chemical composition alone was not sufficient to explain the relative strength of ash-agglomerates. Compositional variation and state of iron within the matrix were assessed through SEM-EDX and electron paramagnetic resonance (EPR) study, respectively. The probing also required the ash-loading and iron-loading factors to be freshly defined in the context of gasification. Localized heat, large compositional variation, presence of iron in Fe2+ state, ash-loading/iron-loading factors influenced intensity of agglomerate formation. Finally, low temperature agglomerate formation was explained by SiO2–Al2O3–FeO phase diagram. - Highlights: • Pilot plant studies on agglomerate formation during high ash coal gasification. • AFT, chemical analysis of coal ash could not give proper indication. • Ash-/iron-loading factors, compositional variation, Fe2+ leads to agglomeration. • Steam to coal ratio was controlled judiciously to avoid agglomeration. • Cause for agglomeration investigated in depth and remedial adjustment was focused

  18. Gasification furnace in a entrained bed flash pyrolysis facility of coal; Kiryuso sekitan kyusoku netsubunkai sochi deno gas ka ro

    Kotsuru, H.; Kawamura, T.; Iida, H.


    This invention aims to present a gasification furnace which gives effectively heat required for coal pyrolysis and secure a sufficient reaction time in the gasification furnace. This invention present a coal gasification furnace to burn char or coal partially with oxygen-containing gas in the coal pyrolysis reactor of a mixture of pulverized coal and a high temperature gas, in which a gas outlet is equipped at the upper part and a slag exhaust is equipped at the lowest part of the cylindrical gasification furnace, more than two blowing inlets for char (or coal) and oxygen-containing gas on the side wall of the furnace symmetrically, and these blowing inlets are arranged to the downward direction more than 5{degree} and less than 30{degree} with a rotating angle more than 5{degree} and less than 50{degree}. The nozzle angle in the gasification furnace of this invention secures the residence time of the particles in the gasification furnace and improves the gasification efficiency. 2 figs., 1 tab.

  19. Numerical and experimental study of strata behavior and land subsidence in an underground coal gasification project

    Sirdesai, N. N.; Singh, R.; Singh, T. N.; Ranjith, P. G.


    Underground Coal Gasification, with enhanced knowledge of hydrogeological, geomechanical and environmental aspects, can be an alternative technique to exploit the existing unmineable reserves of coal. During the gasification process, petro-physical and geomechanical properties undergo a drastic change due to heating to elevated temperatures. These changes, caused due to the thermal anisotropy of various minerals, result in the generation of thermal stresses; thereby developing new fracture pattern. These fractures cause the overhead rock strata to cave and fill the gasification chamber thereby causing subsidence. The degree of subsidence, change in fluid transport and geomechanical properties of the rock strata, in and around the subsidence zone, can affect the groundwater flow. This study aims to predict the thermo-geomechanical response of the strata during UCG. Petro-physical and geomechanical properties are incorporated in the numerical modelling software COMSOL Multiphysics and an analytical strength model is developed to validate and further study the mechanical response and heat conduction of the host rock around the gasification chamber. Once the problems are investigated and solved, the enhanced efficiency and the economic exploitation of gasification process would help meet country's energy demand.

  20. Experimental study on the gasification characteristics of coal and orimulsion in 0.5 T/D gasifier

    Park, Ho Young; Kim, Jong Young; An, Dal Hong; Park, Tae Jun [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center


    For the construction of commercial plant for IGCC imported from aboard in near future, it is aimed to get gasification data, practice the gasification design capability, and develop a fundamental key technology through the experiments for different kinds of coals (Datong, Roto, Alaska) by 0.5 T/D gasifier. We performed the experiments for physical properties and reactivities on selected coals by means of Drop Tube Reactor, numerical analysis for the reactor. Throughout the characteristic studies of orimulsion gasification, feasibility studies for orimulsion gasification as a fuel for power plant be performed. With the six experiment runs for the coal gasifier, several problems were found to remedy. After remedies, the gasifier could run at good operating conditions maintaining with 200% design feed rate over 1200-1550 degree. The third and fourth gasification runs with Roto were satisfactorily completed, during which gross heating values from produced gas were 7200-8200 Kcal/Nm{sup 3}. (author). 118 refs., 145 figs.

  1. Assessment of coal gasification/hot gas cleanup based advanced gas turbine systems


    The major objectives of the joint SCS/DOE study of air-blown gasification power plants with hot gas cleanup are to: (1) Evaluate various power plant configurations to determine if an air-blown gasification-based power plant with hot gas cleanup can compete against pulverized coal with flue gas desulfurization for baseload expansion at Georgia Power Company's Plant Wansley; (2) determine if air-blown gasification with hot gas cleanup is more cost effective than oxygen-blown IGCC with cold gas cleanup; (3) perform Second-Law/Thermoeconomic Analysis of air-blown IGCC with hot gas cleanup and oxygen-blown IGCC with cold gas cleanup; (4) compare cost, performance, and reliability of IGCC based on industrial gas turbines and ISTIG power island configurations based on aeroderivative gas turbines; (5) compare cost, performance, and reliability of large (400 MW) and small (100 to 200 MW) gasification power plants; and (6) compare cost, performance, and reliability of air-blown gasification power plants using fluidized-bed gasifiers to air-blown IGCC using transport gasification and pressurized combustion.

  2. Coal gasification for power generation and methanol synthesis - state of the art

    Sciazko, M. [Inst. for Chemical Processing of Coal, Zabrze (Poland)


    The principal premise for the concept of integrated power and methanol production are successful results of operation of modern gas-steam systems integrated with the coal gasification. The experiences gained on five hitherto utilised demonstrative installations in scale of 100-300 MW{sub e} indicates the possibility of achieving high efficiencies of the transformation into electric energy as well as give the grounds for designing the installations of 1000 MW{sub e}, which means throughput of approximately 450 t coal/h. A new element of developed technologies is utilisation of wastes in a mixture with coal. From the other side commercially operated plants producing methanol based on the coal gasification acting in the USA (LPMEOH) constitute the base for linking both systems with electric energy production. The essence of linking is the full utilization of the coal gasification installation in the event of diminished demand in electric energy. The surplus of gas can be delivered to methanol synthesis which shall make possible to obtain both the high efficiency of the system and economical production. 6 refs., 3 figs., 3 tabs.

  3. Dynamic modeling and control of integrated coal gasification combined cycle units. Doctoral thesis

    Schoen, P.


    This thesis investigates the dynamic behavior and control of integrated coal gasification combined cycle units, operating in a load-following mode on the national grid. Startup, shutdown and accident related behavior are not considered. A conceptual 250 MW unit featuring an oxygen-blown pulverized coal gasifier according to the Shell Coal Gasification Process (SCGP) has been taken as the subject of a simulation study. An attempt at model validation has been made using experimental data from the SCGP demonstration unit in Deer Park, Texas. Using the concept of Model Predictive Control, sample constraints on gasifier conditions and syngas pressure profile were explicitly accounted for in the control algorithm. Whereas the former are found to be easily accommodated without any significant impact on load-following control, the latter inevitably lead to a deterioration in performance. Conclusions and recommendations on dynamic modeling and unit power control are provided.

  4. Co-gasification of Colombian coal and biomass in fluidized bed: An experimental study

    Jhon F. Velez; Farid Chejne; Carlos F. Valdes; Eder J. Emery; Carlos A. Londono [Universidad Nacional de Colombia, Antioquia (Colombia). Grupo de Termodinamica Aplicada y Energias Alternativas


    The main results of an experimental work on co-gasification of Colombian biomass/coal blends in a fluidized bed working at atmospheric pressure are reported in this paper. Several samples of blends were prepared by mixing 6-15wt% biomass (sawdust, rice or coffee husk) with coal. Experimental assays were carried out by using mixtures of different steams/blends (Rvc) and air/blend (Rac) ratios showing the feasibility to implement co-gasification as energetic alternative to produce fuel gas to heat and to generate electricity and the possibility of converting clean and efficiently the refuse coal to a low-heating value gas. 29 refs., 5 figs., 4 tabs.

  5. Improved reactivity of large coal particles by K2CO3 addition during steam gasification

    Coetzee, Sansha; Neomagus, Hein W J P; Bunt, John R.; Everson, Raymond C.


    In this study, the excess solution impregnation method was used to impregnate large coal particles (5 and 10 mm) with K2CO3, and the effect of the additive on steam gasification reactivity was investigated. A washed bituminous, medium rank-C Highveld coal, with an ash content of 12.6 wt.% (air-dried basis), was used for experimentation. The excess solution method was used to impregnate coal particles with the selected additive, K2CO3, and results from XRF analysis indicated that t...

  6. Gasification of Coal and PET in Fluidized Bed Reactor

    Pohořelý, Michael; Vosecký, Martin; Kameníková, Petra; Punčochář, Miroslav; Skoblia, Sergej; Staf, M.; Vošta, J.; Koutský, B.; Svoboda, Karel


    Roč. 85, 17-18 (2006), s. 2458-2468. ISSN 0016-2361 R&D Projects: GA ČR(CZ) GA104/04/0829 Institutional research plan: CEZ:AV0Z40720504 Keywords : fludized bed * gasification * plastic waste Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.358, year: 2006

  7. Gasification of biomass and coal in a pressurised fluidised bed gasifier

    Andries, J.; Jong, W. de; Hein, K.R.G. [Technische Univ. Delft (Netherlands)


    During a 3 year (1996-1998) multinational JOULE project, partly funded by the EU, experimental and theoretical research is being done on co-gasification of biomass (pelletised straw and Miscanthus) and coal in a pressurised fluidised bed reactor. The influence of feedstock and operating conditions on gasification characteristics has been studied using a 1.5 MW{sub th} gasifier, which has been operated at a pressure of 5 bar and temperatures up to 900 C. The project and the test rig are described and results obtained in the first part of the project are presented and analysed. (orig.)

  8. Product Characterization for Entrained Flow Coal/Biomass Co-Gasification

    Maghzi, Shawn [General Electric Global Research, Niskayuna, NY (United States); Subramanian, Ramanathan [General Electric Global Research, Niskayuna, NY (United States); Rizeq, George [General Electric Global Research, Niskayuna, NY (United States); Singh, Surinder [General Electric Global Research, Niskayuna, NY (United States); McDermott, John [General Electric Global Research, Niskayuna, NY (United States); Eiteneer, Boris [General Electric Global Research, Niskayuna, NY (United States); Ladd, David [General Electric Global Research, Niskayuna, NY (United States); Vazquez, Arturo [General Electric Global Research, Niskayuna, NY (United States); Anderson, Denise [General Electric Global Research, Niskayuna, NY (United States); Bates, Noel [General Electric Global Research, Niskayuna, NY (United States)


    The U.S. Department of Energy's National Energy Technology Laboratory (DOE NETL) is exploring affordable technologies and processes to convert domestic coal and biomass resources to high-quality liquid hydrocarbon fuels. This interest is primarily motivated by the need to increase energy security and reduce greenhouse gas emissions in the United States. Gasification technologies represent clean, flexible and efficient conversion pathways to utilize coal and biomass resources. Substantial experience and knowledge had been developed worldwide on gasification of either coal or biomass. However, reliable data on effects of blending various biomass fuels with coal during gasification process and resulting syngas composition are lacking. In this project, GE Global Research performed a complete characterization of the gas, liquid and solid products that result from the co-gasification of coal/biomass mixtures. This work was performed using a bench-scale gasifier (BSG) and a pilot-scale entrained flow gasifier (EFG). This project focused on comprehensive characterization of the products from gasifying coal/biomass mixtures in a high-temperature, high-pressure entrained flow gasifier. Results from this project provide guidance on appropriate gas clean-up systems and optimization of operating parameters needed to develop and commercialize gasification technologies. GE's bench-scale test facility provided the bulk of high-fidelity quantitative data under temperature, heating rate, and residence time conditions closely matching those of commercial oxygen-blown entrained flow gasifiers. Energy and Environmental Research Center (EERC) pilot-scale test facility provided focused high temperature and pressure tests at entrained flow gasifier conditions. Accurate matching of syngas time-temperature history during cooling ensured that complex species interactions including homogeneous and heterogeneous processes such as particle nucleation, coagulation, surface condensation

  9. Product Characterization for Entrained Flow Coal/Biomass Co-Gasification

    Maghzi, Shawn; Subramanian, Ramanathan; Rizeq, George; Singh, Surinder; McDermott, John; Eiteneer, Boris; Ladd, David; Vazquez, Arturo; Anderson, Denise; Bates, Noel


    The U.S. Department of Energy‘s National Energy Technology Laboratory (DOE NETL) is exploring affordable technologies and processes to convert domestic coal and biomass resources to high-quality liquid hydrocarbon fuels. This interest is primarily motivated by the need to increase energy security and reduce greenhouse gas emissions in the United States. Gasification technologies represent clean, flexible and efficient conversion pathways to utilize coal and biomass resources. Substantial experience and knowledge had been developed worldwide on gasification of either coal or biomass. However, reliable data on effects of blending various biomass fuels with coal during gasification process and resulting syngas composition are lacking. In this project, GE Global Research performed a complete characterization of the gas, liquid and solid products that result from the co-gasification of coal/biomass mixtures. This work was performed using a bench-scale gasifier (BSG) and a pilot-scale entrained flow gasifier (EFG). This project focused on comprehensive characterization of the products from gasifying coal/biomass mixtures in a high-temperature, high-pressure entrained flow gasifier. Results from this project provide guidance on appropriate gas clean-up systems and optimization of operating parameters needed to develop and commercialize gasification technologies. GE‘s bench-scale test facility provided the bulk of high-fidelity quantitative data under temperature, heating rate, and residence time conditions closely matching those of commercial oxygen-blown entrained flow gasifiers. Energy and Environmental Research Center (EERC) pilot-scale test facility provided focused high temperature and pressure tests at entrained flow gasifier conditions. Accurate matching of syngas time-temperature history during cooling ensured that complex species interactions including homogeneous and heterogeneous processes such as particle nucleation, coagulation, surface condensation, and

  10. Thermodynamic analyses of solar thermal gasification of coal for hybrid solar-fossil power and fuel production

    Thermodynamic analyses are performed for solar thermal steam and dry gasification of coal. The selected types of coal are anthracite, bituminous, lignite and peat. Two model conversion paths are considered for each combination of the gasifying agent and the coal type: production of the synthesis gas with its subsequent use in a combined cycle power plant to generate power, and production of the synthesis gas with its subsequent use to produce gasoline via the Fischer–Tropsch synthesis. Replacement of a coal-fired 35% efficient Rankine cycle power plant and a combustion-based integrated gasification combined cycle power plant by a solar-based integrated gasification combined cycle power plant leads to the reduction in specific carbon dioxide emissions by at least 47% and 27%, respectively. Replacement of a conventional gasoline production process via coal gasification and a subsequent Fischer–Tropsch synthesis with gasoline production via solar thermal coal gasification with a subsequent Fischer–Tropsch synthesis leads to the reduction in specific carbon dioxide emissions by at least 39%. -- Highlights: ► Thermodynamic analyses for steam and dry gasification of coal are presented. ► Hybrid solar-fossil paths to power and fuels are compared to those using only combustion. ► Hybrid power production can reduce specific CO2 emissions by more than 27%. ► Hybrid fuel production can reduce specific CO2 emissions by more than 39%.

  11. Joint European project on underground coal gasification in Spain; Proyecto europeo conjunto de gasificacion subterranea de carbon en Espana

    Gonzalez, J.M.; Obis, A.; Menendez, E.; Albeniz, M.A.; Chandelle, V.; Mostade, M.; Bailey, A.C. [ITGE, Madrid (Spain)


    Organizations from Spain, Belgium and the United Kingdom are collaborating in a field test of underground coal gasification which is being implemented in the north of Teruel Province (Spain). The test is first phase of a European development programme on in-situ coal gasification, being carried out with financial help from the Commission of the European Communities. This paper covers a forecast of the future energy demand for Europe, the potential of in-situ coal gasification, and a summary of the recent development of in-situ coal gasification. The circumstances which led to the formation of a European organisation (UEE) which will implement the project are described, and its objectives are presented. The geological characteristics of the proposed region are detailed, together with the test programme, and its successive phases in realising the principle parameters of the operations.

  12. TVA coal-gasification commercial demonstration plant project. Volume 5. Plant based on Koppers-Totzek gasifier. Final report


    This volume presents a technical description of a coal gasification plant, based on Koppers-Totzek gasifiers, producing a medium Btu fuel gas product. Foster Wheeler carried out a conceptual design and cost estimate of a nominal 20,000 TPSD plant based on TVA design criteria and information supplied by Krupp-Koppers concerning the Koppers-Totzek coal gasification process. Technical description of the design is given in this volume.

  13. Slag Behavior in Gasifiers. Part I: Influence of Coal Properties and Gasification Conditions

    Ping Wang


    Full Text Available In the entrained-flow gasifiers used in integrated gasification combined cycle (IGCC plants, the majority of mineral matter transforms to liquid slag on the wall of the gasifier and flows out the bottom. However, a small fraction of the mineral matter is entrained (as fly ash with the raw syngas out of the gasifier to downstream processing. This molten/sticky fly ash could cause fouling of the syngas cooler. To improve gasification availability through better design and operation of the gasification process, a better understanding of slag behavior and the characteristics of the slagging process is needed. Char/ash properties, gas compositions in the gasifier, the gasifier wall structure, fluid dynamics, and plant operating conditions (mainly temperature and oxygen/carbon ratio all affect slagging behavior. Because coal has varying ash content and composition, different operating conditions are required to maintain the slag flow and limit problems downstream. In Part I, we review the main types and the operating conditions of entrained-flow gasifiers and coal properties used in IGCC plants; we identify and discuss the key coal ash properties and the operating conditions impacting slag behavior; finally, we summarize the coal quality criteria and the operating conditions in entrained-flow gasifiers. In Part II, we discuss the constitutive modeling related to the rheological studies of slag flow.

  14. Theoretical and experimental studies of fixed-bed coal gasification reactors. Final report

    Joseph, B.; Bhattacharya, A.; Salam, L.; Dudukovic, M.P.


    A laboratory fixed-bed gasification reactor was designed and built with the objective of collecting operational data for model validation and parameter estimation. The reactor consists of a 4 inch stainless steel tube filled with coal or char. Air and steam is fed at one end of the reactor and the dynamic progress of gasification in the coal or char bed is observed through thermocouples mounted at various radial and axial locations. Product gas compositions are also monitored as a function of time. Results of gasification runs using Wyoming coal are included in this report. In parallel with the experimental study, a two-dimensional model of moving bed gasifiers was developed, coded into a computer program and tested. This model was used to study the laboratory gasifier by setting the coal feed rate equal to zero. The model is based on prior work on steady state and dynamic modeling done at Washington University and published elsewhere in the literature. Comparisons are made between model predictions and experimental results. These are also included in this report. 23 references, 18 figures, 6 tables.

  15. Integrated drying and gasification: technology for power generation from brown coal and biomass

    The fact that 2% of Australia's electricity generation needs to be derived from new renewable energy sources by the year 2010 limits the fuel/energy options in the short term, simply from the sheer size of the undertaking, namely some 9000 GWh of electricity is required from new renewables alone. Realistically, this target can only be achieved by using biomass as the major fuel/energy source. The increasing government, scientific and community pressures to reduce greenhouse gas emissions has focussed particular emphasis on the use of renewable fuels for electricity and heating applications. Various biomass fuels such as agricultural residues, forestry wastes and special energy crops have been targeted as sources. Small and large- scale tests have been conducted in various combustion and gasification equipment facilities especially in Europe and to a lesser extent in Australia. Several operational issues, e.g. chloride removal, slagging, need further resolution. A major factor in the introduction of biomass gasification is the comparative cost with existing coal-fired facilities for producing electricity. However, co-firing of biomass with coal appears to be a less costly option. Nonetheless, biomass gasification technologies are being actively demonstrated and show enhanced efficiency. The IDGCC process is designed to produce electricity at low cost and high efficiency from low-rank coals. These high moisture coals are available at low cost in many countries and their use would reduce imports of black coal or other fuels. The process has been shown to operate successfully at the 10 MW scale and the technology is ready to be applied to a commercially scale plant in the 120 to 400 MW scale plants. The drying and gasification part of IDGCC, i.e. IDG, is a suitable means of preparing biomass for co-firing in existing boiler plant, with advantages in simplifying fuel size reduction and in keeping undesirable inorganic constituents out of the boiler

  16. Underground Coal Gasification: Rates of Post Processing Gas Transport

    Soukup, K.; Hejtmánek, V. (Vladimír); Stanczyk, K.; Šolcová, O.


    Two ex-situ and one in-situ semi-pilot plant UCG experiments in the experimental mine Barbara were performed with hard coal and lignite samples. To evaluate the influence of the UCG process on the textural properties of surrounding strata and coals, samples from various locations of the coal seam and the stratum samples before and after the UCG process were collected. Mercury porosimetry, helium pycnometry, and physical adsorption of nitrogen were used for the determination of textural proper...

  17. Differences in physical properties and CO{sub 2} gasification reactivity between coal char and petroleum coke

    Wu, Y.Q.; Wu, S.Y.; Gu, J.; Gao, J.S. [East China University of Science & Technology, Shanghai (China)


    This paper mainly investigated the physical properties and gasification reactivity of coal char and petroleum coke, separately at the high temperature pyrolysis (950-1400{sup o}C) with slow heating rate and pyrolysis pressure of the atmospheric pressure and at the pressurized pyrolysis (the atmospheric pressure to 3 MPa) with rapid heating rate and the pyrolysis temperature of 950{sup o}C. Some significant differences in those between coal chars and petroleum coke were found. The high temperature pyrolysis caused more easily the graphitization of petroleum coke than that of coal char, especially in the higher temperature range. The increasing pyrolysis temperature resulted in the decrease of surface areas of coal char and the increase of surface areas of petroleum coke. As the pyrolysis pressure was elevated from the atmospheric pressure to 3 MPa, surface areas of petroleum coke initially increased and then decreased, while those of coal chars presented an opposite tendency. The increasing pyrolysis temperature was adverse to the gasification activity of coal chars and was favorable for the gasification activity of petroleum coke. Also, the effects of the pyrolysis pressure on the gasification activity of coal char and petroleum coke were significantly different. The gasification activity of petroleum coke was obviously lower than that of coal chars, and even lower than that of the natural graphite.


    The report gives results of the chemical and mineralogical characterization of coal solid wastes. The wastes included three Lurgi gasification ashes, mineral residues from the SRC-1 and H-Coal liquefaction processes, two chars, two coal-cleaning residues, and a fly-ash-and-water-...

  19. A comparison of gasification phenomena among raw biomass, torrefied biomass and coal in an entrained-flow reactor

    Highlights: ► Gasification phenomena of raw bamboo, torrefied bamboo, and coal are studied. ► The carbon conversions of the three fuels are higher than 90%. ► The coal gas efficiency is sensitive to the type of fuel. ► The gasification performance of torrefied bamboo is enhanced and closer to that of coal. ► With optimum operation, syngas formation from torrefied biomass is amplified by 88%. - Abstract: Gasification of torrefied biomass is a promising technique for producing synthesis gas (syngas) of higher quality than has previously been available. In this study, in order to evaluate the potential of the technique, gasification processes for three different materials, which include raw bamboo, torrefied bamboo (at 280 °C for 1 h), and high-volatile bituminous coal in an entrained-flow gasifier using O2 as the gasification agent, are studied numerically and compared to each other. The obtained results suggest that in all cases, the carbon conversions of the three fuels are higher than 90%. However, the cold gasification efficiency for raw bamboo is low, mainly due to the relatively lower calorific value of the material. In the case of the torrefied bamboo fuel, the gasification performance is enhanced significantly and is quite similar to the coal gasification under the same conditions. It appears that the optimum oxygen-to-fuel mass flow ratios for the gasification of raw bamboo, torrefied bamboo, and coal are 0.9, 0.7, and 0.7, and their equivalence ratios are 0.692, 0.434, and 0.357, respectively. Under optimum conditions with respect to the equivalence ratio, the cold gas efficiency of torrefied bamboo is improved by 88%, as compared to raw bamboo

  20. Manipulation of gasification coal feed in order to increase the ash fusion temperature of the coal to operate the gasifiers at higher temperatures / Johannes Chrisstoffel van Dyk

    Van Dyk, Johannes Chrisstoffel


    Coal is a crucial feedstock for South Africa's unique synfuels and petrochemicals industry and used by Sasol as a feedstock to produce synthesis gas via the Sasol-Lurgi Fixed Bed Dry Bottom (FBDB) gasification process. The ash fusion temperature (AFT) gives detail information on the suitability of a coal source for gasification purposes, and specifically to the extent ash agglomeration or clinkering is likely to occur within the gasifier. Ash clinkering inside the gasifier can cause channel b...

  1. An effect of Blade geometry on heat transfer performance in stirred vessel – coal water slurry system using coal gasification

    C.M.Raguraman,; Ragupathy, A.; R. Ramkumar,; L.Sivakumar


    The effect of the geometrical parameter of blades on heat transfer co-efficient were experimentally studied for agitated vessels using coal slurry in coal gasification. The intensity of hear transfer during mixing of fluids depends on the type of the stirrer, the design of the vessel and conditions of the process. The type and size of the stirrer, as well as its location in the vessel, also affect the rate of hear transfer. In this study, the effect of some importantdesign parameter such as t...

  2. Chemical-Looping Combustion and Gasification of Coals and Oxygen Carrier Development: A Brief Review

    Ping Wang


    Full Text Available Chemical-looping technology is one of the promising CO2 capture technologies. It generates a CO2 enriched flue gas, which will greatly benefit CO2 capture, utilization or sequestration. Both chemical-looping combustion (CLC and chemical-looping gasification (CLG have the potential to be used to generate power, chemicals, and liquid fuels. Chemical-looping is an oxygen transporting process using oxygen carriers. Recently, attention has focused on solid fuels such as coal. Coal chemical-looping reactions are more complicated than gaseous fuels due to coal properties (like mineral matter and the complex reaction pathways involving solid fuels. The mineral matter/ash and sulfur in coal may affect the activity of oxygen carriers. Oxygen carriers are the key issue in chemical-looping processes. Thermogravimetric analysis (TGA has been widely used for the development of oxygen carriers (e.g., oxide reactivity. Two proposed processes for the CLC of solid fuels are in-situ Gasification Chemical-Looping Combustion (iG-CLC and Chemical-Looping with Oxygen Uncoupling (CLOU. The objectives of this review are to discuss various chemical-looping processes with coal, summarize TGA applications in oxygen carrier development, and outline the major challenges associated with coal chemical-looping in iG-CLC and CLOU.

  3. Release of inorganic trace elements from high-temperature gasification of coal

    Blaesing, Marc


    The development of cleaner, more efficient techniques in next-generation coal power plants is becoming increasingly important, especially regarding to the discussion of the influence of CO{sub 2} emissions on global warming. A promising coal utilisation process is the integrated gasification combined cycle process. The direct use of the raw gas requires gas clean-up to prevent downstream parts of the gasifier from several problems. An increased efficiency and a decreased amount of harmful species can be achieved through hot fuel gas cleaning. This clean-up technique requires a comprehensive knowledge of the release characteristics of inorganic coal constituents. The aim of this thesis was to provide enhanced knowledge of the effect of key process parameters and of the chemical constitution of coal on the release of Na, K, S, and Cl species from high-temperature coal gasification. The experimental setup consisted of atmospheric flow tube furnaces and a pressurised furnace. In-situ analysis of the product gas was carried out using molecular beam mass spectrometry. A broad spectrum of different coals with assumed qualitative and quantitative differences in the release characteristics was investigated. Additionally, experiments with model substances were performed. The results of the experimental investigation were compared with thermodynamic calculations. Finally, recommendations, for the operation of a high-temperature gasifier are formulated. (orig.)

  4. Method of oxygen-enriched two-stage underground coal gasification

    Liu Hongtao; Chen Feng; Pan Xia; Yao Kai; Liu Shuqin


    Two-stage underground coal gasification was studied to improve the caloric value of the syngas and to extend gas production times. A model test using the oxygen-enriched two-stage coal gasification method was carried out. The composition of the gas produced, the time ratio of the two stages, and the role of the temperature field were analysed. The results show that oxygen-enriched two-stage gasification shortens the time of the first stage and prolongs the time of the second stage. Feed oxygen concentrations of 30%,35%, 40%, 45%, 60%, or 80% gave time ratios (first stage to second stage) of 1:0.12, 1:0.21, 1:0.51, 1:0.64,1:0.90, and 1:4.0 respectively. Cooling rates of the temperature field after steam injection decreased with time from about 19.1-27.4 ℃/min to 2.3-6.8 ℃/min. But this rate increased with increasing oxygen concentrations in the first stage. The caloric value of the syngas improves with increased oxygen concentration in the first stage. Injection of 80% oxygen-enriched air gave gas with the highest caloric value and also gave the longest production time. The caloric value of the gas obtained from the oxygenenriched two-stage gasification method lies in the range from 5.31 MJ/Nm3 to 10.54 MJ/Nm3.

  5. Three Stage Equilibrium Model for Coal Gasification in Entrained Flow Gasifiers Based on Aspen Plus

    KONG Xiangdong; ZHONG Weimin; DU Wenli; QIAN Feng


    A three stage equilibrium model is developed for coal gasification in the Texaco type coal gasifiers based on Aspen Plus to calculate the composition of product gas,carbon conversion,and gasification temperature.The model is divided into three stages including pyrolysis and combustion stage,char gas reaction stage,and gas phase reaction stage.Part of the water produced in the pyrolysis and combustion stage is assumed to be involved in the second stage to react with the unburned carbon.Carbon conversion is then estimated in the second stage by steam participation ratio expressed as a function of temperature.And the gas product compositions are calculated from gas phase reactions in the third stage.The simulation results are consistent with published experimental data.

  6. Development of a thermo-mechanical model for rocks exposed to high temperatures during underground coal gasification

    Tian, Hong


    In the wake of increasing challenges of high prices of oil and gas and uncertainties about political stability in many oil and gas producing countries, coal becomes more and more important in the coming years for its vast reserves and wide distribution all over the world. The technology of Underground Coal Gasification (UCG), converting in-situ, unmined coal into combustible gases, has continued to attract worldwide interest because of its ability to exploit coal which is otherwise unminable ...

  7. The evolution of gasification processes and reactors and the utilization of the coal gas. A proposition for the implementation of the gasification technology

    Thermochemical treatment of coal by gasification, considered as a non-polluting technology to turn the coal highly-profitably is one of the alternative ways to produce gas with a high effective caloric capacity. Due to its advantages, the gasification has made through the last few decades significant advances from the point of view of the process efficiency (chemical, thermal), of motor outputs (in m3 producer gas / m2 reactor cross section x hour), of the solutions of supplying energy to support the endothermic reactions implied by the process, and especially of the reactors. Reactors have been developed from gas generators. Starting from gas generators various advanced reactors (of 1 st to 3 rd generation) have been developed to produce air gas, water gas or mixed gas. Applications of the producer gas were developed using it either as fuel or as synthesis gas in chemical industry or else as a substitute to the natural gas in combined cycle gas turbines where the gasification plant was integrated. In Romania there are projects in the field of coal gasification, namely at ICPET-RESEARCH, that can offer advanced technologies. One of these projects deals with the construction of the first demonstrative gasification plant based on a highly efficient process and equipped with a 10 G cal/h reactor. (author). 1 tab., 12 refs

  8. Behaviour of selected major elements during fixed-bed gasification of South African bituminous coal

    Bunt, J.R.; F.B. Waanders; Schobert, H.


    The Sasol-Lurgi Fixed Bed Dry Bottom gasifier (S-L FBDB) treats a feed coal containing c.a. 30% ash forming minerals, which means that there are complex mineralogical processes occurring simultaneously with each other, and in the gasification reactions, within the reactor. To obtain an understanding of the mineral transformational behaviour, a quenched commercial-scale S-L FBDB gasifier was sampled and characterized mineralogically. Crystalline phases measured by XRD analyses show the ash exi...

  9. Gas Production Strategy of Underground Coal Gasification Based on Multiple Gas Sources

    Duan Tianhong; Wang Zuotang; Zhou Limin; Li Dongdong


    To lower stability requirement of gas production in UCG (underground coal gasification), create better space and opportunities of development for UCG, an emerging sunrise industry, in its initial stage, and reduce the emission of blast furnace gas, converter gas, and coke oven gas, this paper, for the first time, puts forward a new mode of utilization of multiple gas sources mainly including ground gasifier gas, UCG gas, blast furnace gas, converter gas, and coke oven gas and the new mode was...

  10. Energy and cost analysis of small-size integrated coal gasification and syngas storage power plants

    Highlights: ► The option of syngas storage in small size coal gasification power plants is proposed. ► Syngas storage enhances flexibility and load modulation capabilities of coal gasification power plants. ► Performance and energy production costs greatly depend on the required peaking energy production. ► Solutions based on internal combustion engines perform better than solutions based on gas turbines. ► Peaking energy production costs are comparable with those of conventional peaking units. - Abstract: This study evaluates the energy and economic performance of small and medium size coal gasification power plants integrated with a syngas storage section (ICGSS). In ICGSS systems, a portion of the produced syngas is stored during periods of low energy demand and used to increase power output during periods of peaking demand, so that they can perform a load-following service and can operate in the electricity markets for energy and spinning reserve. The main energy and economic performance of ICGSS power generation plants were evaluated with reference to two different prime movers (gas turbines and internal combustion engines) and as a function of the required electrical load curve. Moreover, a preliminary economic analysis was also carried out to evaluate the peak-load energy production cost in comparison with base-load energy production cost. The results of the study show that ICGSS power plants offer considerable scope for enhancing operating flexibility and load modulation capabilities of coal gasification power plants. Plant options based on internal combustion engines performed better than options based on gas turbines.

  11. Production of synthesis gas and methane via coal gasification utilizing nuclear heat

    The steam gasificaton of coal requires a large amount of energy for endothermic gasification, as well as for production and heating of the steam and for electricity generation. In hydrogasification processes, heat is required primarily for the production of hydrogen and for preheating the reactants. Current developments in nuclear energy enable a gas cooled high temperature nuclear reactor (HTR) to be the energy source, the heat produced being withdrawn from the system by means of a helium loop. There is a prospect of converting coal, in optimal yield, into a commercial gas by employing the process heat from a gas-cooled HTR. The advantages of this process are: (1) conservation of coal reserves via more efficient gas production; (2) because of this coal conservation, there are lower emissions, especially of CO2, but also of dust, SO2, NO/sub x/, and other harmful substances; (3) process engineering advantages, such as omission of an oxygen plant and reduction in the number of gas scrubbers; (4) lower gas manufacturing costs compared to conventional processes. The main problems involved in using nuclear energy for the industrial gasification of coal are: (1) development of HTRs with helium outlet temperatures of at least 9500C; (2) heat transfer from the core of the reactor to the gas generator, methane reforming oven, or heater for the hydrogenation gas; (3) development of a suitable allothermal gas generator for the steam gasification; and (4) development of a helium-heated methane reforming oven and adaption of the hydrogasification process for operation in combination with the reactor. In summary, processes for gasifying coal that employ heat from an HTR have good economic and technical prospects of being realized in the future. However, time will be required for research and development before industrial application can take place. 23 figures, 4 tables. (DP)

  12. A Study on the Applicability of Kinetic Models for Shenfu Coal Char Gasification with CO2 at Elevated Temperatures

    Jinsheng Gao


    Full Text Available In this paper, measurements of the CO2 gasification kinetics for two types of Shenfu coal chars, which were respectively prepared by slow and rapid pyrolysis at temperatures of 950 °C and 1,400 °C, were performed by an isothermal thermo-gravimetric analysis under ambient pressure and elevated temperature conditions. Simultaneously, the applicability of the kinetic model for the CO2 gasification reaction of Shenfu coal chars was discussed. The results showed: (i the shrinking un-reacted core model was not appropriate to describe the gasification reaction process of Shenfu coal chars with CO2 in the whole experimental temperature range; (ii at the relatively low temperatures, the modified volumetric model was as good as the random pore model to simulate the CO2 gasification reaction of Shenfu coal chars, while at the elevated temperatures, the modified volumetric model was superior to the random pore model for this process; (iii the integral expression of the modified volumetric model was more favorable than the differential expression of that for fitting the experimental data. Moreover, by simply introducing a function: A = A★exp(ft, it was found that the extensive model of the modified volumetric model could make much better predictions than the modified volumetric model. It was recommended as a convenient empirical model for comprehensive simulation of Shenfu coal char gasification with under conditions close to those of entrained flow gasification.

  13. Development and demonstration plant operation of an opposed multi-burner coal-water slurry gasification technology

    WANG Fuchen; ZHOU Zhijie; DAI Zhenhua; GONG Xin; YU Guangsuo; LIU Haifeng; WANG Yifei; YU Zunhong


    The features of the opposed multi-burner (OMB) gasification technology,the method and process of the research,and the operation results of a pilot plant and demon stration plants have been introduced.The operation results of the demonstration plants show that when Beisu coal was used as feedstock,the OMB CWS gasification process at Yankuang Cathy Coal Co.Ltd had a higher carbon conversion of 3%,a lower specific oxygen consumption of about 8%,and a lower specific carbon consumption of 2%-3% than that of Texaco CWS gasification at the Lunan Fertilizer Plant.When Shenfu coal was used as feedstock,the OMB CWS gasification process at Hua-lu Heng-sheng Chemical Co.Ltd had a higher carbon conversion of more than 3%,a lower specific oxygen consumption of about 2%,and a lower specific coal consumption of about 8% than that of the Texaco CWS gasification process at Shanghai Coking & Chemical Corporation.The OMB CWS gasification technology is proven by industrial experience to have a high product yield,low oxygen and coal consumption and robust and safe operation.

  14. 煤制甲醇项目的煤气化技术选择%Selection of coal gasification technology for coal-to-methanol project

    冯亮杰; 郑明峰; 尹晓晖; 张骏驰


    Elaborate the necessity of developing coal-to-methanol project in China, taking coal derived DME project as an example, analyze the influence of various coal-gasification techniques on installation scale, technical route,technical economy. The results show that slurry gasification technique is the best among overall indices of water coal slurry gasification technique under the conditions of high slurry ability of feed coal water slurry.%阐述了中国发展煤制甲醇的重要性,以煤制二甲醚为例分析了不同煤气化技术对装置规模、技术路线及技术经济的影响.结果表明,在原料煤具有良好成浆性的情况下,综合技术经济指标以水煤浆气化技术最好.

  15. ABB combustion engineering coal gasification system for combined cycle power generation

    Andrus, H.E.; Mirolli, M.D.; Vroom, H.H. (ABB Combustion Engineering (United States))


    ABB Combustion Engineering is one of the main suppliers of equipment to IGCC projects. It supplied the heat recovery boilers and gasifier vessel at Texaco's Coal Water IGCC demonstration plant in California. Complete plants can be constructed, from coal grinding and preparation; through char removal and recycle; to hot gas cleanup. The low BTU gases produced can be burnt in a standard gas turbine. ABB-CE is developing an air blown IGCC technology for the power industry, comprising a two-stage, entrained flow, air blown, slagging bottom gasification process. The air blown model offers a simplicity that should increase reliability and reduce maintenance costs. 2 refs., 7 figs.

  16. Thermodynamic analysis of a coal gasification and split Rankine combined cogeneration plant. Part 1: energy analysis

    De, S.; Biswal, S.K. [Jadavpur University, Calcutta (India). Dept. of Mechanical Engineering


    The aim of this paper is to study the thermodynamic performance of a new combination of a coal gasification topping gas cycle and an 'externally coupled', 'split Rankine' bottoming steam cycle as a means of advanced clean coal combined cogeneration. Energy analysis of the conceptualized cogeneration scheme is presented in this part of the paper. The effects of the design and operating parameters of both the gas and the steam cycle on the performance of the combined heat and power plant are discussed.

  17. Energy and Entropy Fluxes in Coal Gasification and Liquefaction Processes

    H. Voigt


    In the long-term studies on energy systems performed at IIASA, scenarios that provide for substitutes for fossil oil and gas are considered. In the future coal is expected to contribute to energy supplies to a greatly increasing extent only if it is converted to liquid or gaseous fuels or electricity. Coal conversion systems are rather complex, not only internally but also with respect to their exchanges with the environment; some use auxiliary energy, others yield byproducts. Therefore, the ...

  18. Environmental and technical aspects of the utilization of SRC, AFBC, and low-Btu coal gasification in industrial processes

    Dauzvardis, P.A.; Brown, C.D.; Hamilton, R.W.; Habegger, L.J.


    The decreasing availability of oil and natural gas has stimulated the search for industrial coal-utilization methods that are alternatives to conventional coal combustion. Three such alternative methods discussed in this report are solvent refined coal (SRC-I), atmospheric fluidized bed combustion (AFBC), and low-Btu coal gasification. Clean low-Btu gas and SRC may have several nonboiler industrial applications. In contrast to conventional coal combustion, use of these fuels has the potential for reduced environmental impact at the industrial plant site, although the impact of coal mining and transportation will be higher. The impact of coal gasification and liquefaction on occupational health and safety will cause the greatest concern.

  19. Measurements of Gasification Characteristics of Coal and Char in CO2-Rich Gas Flow by TG-DTA

    Zhigang Li


    Full Text Available Pyrolysis, combustion, and gasification properties of pulverized coal and char in CO2-rich gas flow were investigated by using gravimetric-differential thermal analysis (TG-DTA with changing O2%, heating temperature gradient, and flow rate of CO2-rich gases provided. Together with TG-DTA, flue gas generated from the heated coal, such as CO, CO2, and hydrocarbons (HCs, was analyzed simultaneously on the heating process. The optimum O2% in CO2-rich gas for combustion and gasification of coal or char was discussed by analyzing flue gas with changing O2 from 0 to 5%. The experimental results indicate that O2% has an especially large effect on carbon oxidation at temperature less than 1100°C, and lower O2 concentration promotes gasification reaction by producing CO gas over 1100°C in temperature. The TG-DTA results with gas analyses have presented basic reference data that show the effects of O2 concentration and heating rate on coal physical and chemical behaviors for the expected technologies on coal gasification in CO2-rich gas and oxygen combustion and underground coal gasification.

  20. Control of combustion area using electrical resistivity method for underground coal gasification

    Selivanova Tatiana; Grebenyuk Igor; Belov Alexey


    Underground coal gasification (UCG) is one of the clean technologies to collect heat energy and gases (hydrogen,methane,etc.) in an underground coal seam.It is necessary to further developing environmentally friendly UCG system construction.One of the most important UCG's problems is underground control of combustion area for efficient gas production,estimation of subsidence and gas leakage to the surface.For this objective,laboratory experiments were conducted according to the UCG model to identify the process of combustion cavity development by monitoring the electrical resistivity activity on the coal samples to setup fundamental data for the technology engineering to evaluate combustion area.While burning coal specimens,that had been sampled from various coal deposits,electrical resistivity was monitored.Symmetric four electrodes system (ABMN) of direct and low-frequency current electric resistance method was used.for laboratory resistivity measurement of rock samples.Made research and the results suggest that front-end of electro conductivity activity during heating and combusting of coal specimen depended on heating temperature.Combusting coal electro conductivity has complicated multistage type of change.Electrical resistivity method is expected to be a useful geophysical tool to for evaluation of combustion volume and its migration in the coal seam.

  1. Gasification Studies Task 4 Topical Report, Utah Clean Coal Program

    Whitty, Kevin [Univ. of Utah, Salt Lake City, UT (United States); Fletcher, Thomas [Univ. of Utah, Salt Lake City, UT (United States); Pugmire, Ronald [Univ. of Utah, Salt Lake City, UT (United States); Smith, Philip [Univ. of Utah, Salt Lake City, UT (United States); Sutherland, James [Univ. of Utah, Salt Lake City, UT (United States); Thornock, Jeremy [Univ. of Utah, Salt Lake City, UT (United States); Hunsacker, Isaac [Univ. of Utah, Salt Lake City, UT (United States); Li, Suhui [Univ. of Utah, Salt Lake City, UT (United States); Kelly, Kerry [Univ. of Utah, Salt Lake City, UT (United States); Puntai, Naveen [Univ. of Utah, Salt Lake City, UT (United States); Reid, Charles [Univ. of Utah, Salt Lake City, UT (United States); Schurtz, Randy [Univ. of Utah, Salt Lake City, UT (United States)


    A key objective of the Task 4 activities has been to develop simulation tools to support development, troubleshooting and optimization of pressurized entrained-flow coal gasifiers. The overall gasifier models (Subtask 4.1) combine submodels for fluid flow (Subtask 4.2) and heat transfer (Subtask 4.3) with fundamental understanding of the chemical (Subtask 4.4) and physical (Subtask 4.5) processes that take place as coal particles are converted to synthesis gas and slag. However, it is important to be able to compare predictions from the models against data obtained from actual operating coal gasifiers, and Subtask 4.6 aims to provide an accessible, non-proprietary system, which can be operated over a wide range of conditions to provide well-characterized data for model validation.

  2. Coal gasification power generation, and product market study. Topical report, March 1, 1995--March 31, 1996

    Sheesley, D.; King, S.B.


    This Western Research Institute (WRI) project was part of a WRI Energy Resource Utilization Program to stimulate pilot-scale improved technologies projects to add value to coal resources in the Rocky Mountain region. The intent of this program is to assess the application potential of emerging technologies to western resources. The focus of this project is on a coal resource near the Wyoming/Colorado border, in Colorado. Energy Fuels Corporation/Kerr Coal Company operates a coal mine in Jackson County, Colorado. The coal produces 10,500 Btu/lb and has very low sulfur and ash contents. Kerr Coal Company is seeking advanced technology for alternate uses for this coal. This project was to have included a significant cost-share from the Kerr Coal Company ownership for a market survey of potential products and technical alternatives to be studied in the Rocky Mountain Region. The Energy Fuels Corporation/Kerr Coal Company and WRI originally proposed this work on a cost reimbursable basis. The total cost of the project was priced at $117,035. The Kerr Coal Company had scheduled at least $60,000.00 to be spent on market research for the project that never developed because of product market changes for the company. WRI and Kerr explored potential markets and new technologies for this resource. The first phase of this project as a preliminary study had studied fuel and nonfuel technical alternatives. Through related projects conducted at WRI, resource utilization was studied to find high-value materials that can be targeted for fuel and nonfuel use and eventually include other low-sulfur coals in the Rocky Mountain region. The six-month project work was spread over about a three-year period to observe, measure, and confirm over time-any trends in technology development that would lead to economic benefits in northern Colorado and southern Wyoming from coal gasification and power generation.

  3. Storing syngas lowers the carbon price for profitable coal gasification.

    Newcomer, Adam; Apt, Jay


    Integrated gasification combined cycle (IGCC) electric power generation systems with carbon capture and sequestration have desirable environmental qualities but are not profitable when the carbon dioxide price is less than approximately $50 per metric ton. We examine whether an IGCC facility that operates its gasifier continuously butstores the syngas and produces electricity only when daily prices are high may be profitable at significantly lower CO2 prices. Using a probabilistic analysis, we have calculated the plant-level return on investment (ROI) and the value of syngas storage for IGCC facilities located in the U.S. Midwest using a range of storage configurations. Adding a second turbine to use the stored syngas to generate electricity at peak hours and implementing 12 h of above-ground high-pressure syngas storage significantly increases the ROI and net present value. Storage lowers the carbon price at which IGCC enters the U.S. generation mix by approximately 25%. PMID:18186325

  4. Coal gasification by indirect heating in a single moving bed reactor: Process development & simulation

    Junaid Akhlas


    Full Text Available In this work, the development and simulation of a new coal gasification process with indirect heat supply is performed. In this way, the need of pure oxygen production as in a conventional gasification process is avoided. The feasibility and energetic self-sufficiency of the proposed processes are addressed. To avoid the need of Air Separation Unit, the heat required by gasification reactions is supplied by the combustion flue gases, and transferred to the reacting mixture through a bayonet heat exchanger installed inside the gasifier. Two alternatives for the flue gas generation have been investigated and compared. The proposed processes are modeled using chemical kinetics validated on experimental gasification data by means of a standard process simulator (Aspen PlusTM, integrated with a spreadsheet for the modeling of a special type of heat exchanger. Simulation results are presented and discussed for proposed integrated process schemes. It is shown that they do not need external energy supply and ensure overall efficiencies comparable to conventional processes while producing syngas with lower content of carbon dioxide.

  5. Biological production of ethanol from coal. Final report


    Due to the abundant supply of coal in the United States, significant research efforts have occurred over the past 15 years concerning the conversion of coal to liquid fuels. Researchers at the University of Arkansas have concentrated on a biological approach to coal liquefaction, starting with coal-derived synthesis gas as the raw material. Synthesis gas, a mixture of CO, H{sub 2}, CO{sub 2}, CH{sub 4} and sulfur gases, is first produced using traditional gasification techniques. The CO, CO{sub 2} and H{sub 2} are then converted to ethanol using a bacterial culture of Clostridium 1jungdahlii. Ethanol is the desired product if the resultant product stream is to be used as a liquid fuel. However, under normal operating conditions, the ``wild strain`` produces acetate in favor of ethanol in conjunction with growth in a 20:1 molar ratio. Research was performed to determine the conditions necessary to maximize not only the ratio of ethanol to acetate, but also to maximize the concentration of ethanol resulting in the product stream.

  6. Saving fuel: thermochemical regeneration and a new method for coal gasification

    Nosach, V.G.


    Based on predictions for the year 2000 up to 80 percent of the energy in the world will be produced on the basis of organic fuels, the demand for which may be reduced through regeneration of heat in thermal power plants. Along with the widely used regenerative heating of air through the heat of spent gases, methods for thermochemical regeneration with intracycle conversion of the initial fuel and pretransformation of low potential heat will be introduced. Pregasification and two staged systems for igniting rock coal are expedient. A method for two staged, high temperature thermochemical processing of dust form solid fuels, which was developed and is being experimentally tested in the Institute of Electrodynamics of the Ukrainian SSR Academy of Sciences, is promising for highly effective gas electric power generators. The first state, gasification, is accomplished in conditions of high speed heating (thermal shock) with an excess of the reducer, while the second, the oxidational stage, is conducted with combustion of coke particles in a medium with an excess of oxidizing agent. The institute has combined with the Institute of High Temperatures of the USSR Academy of Science to develop a method for continuous production of synthesis gas (a gas like energy carrier) through vapor gasification, where the energy source for compensating for the endothermal effect of the vapor gasification is the energy of the burning coal itself.

  7. Coal gasification and liquefaction as substitutes for petroleum and natural gas - possibilities and limitations

    There are four processes by which coal can be converted into a marketable secondary energy source: 1. Coking: Most of the coke produced is used in the steel-producing industry. 2. Electric power generation, mainly for base load power supply. Here, coal must be supplemented by nuclear power to an increasing extent. 3. Hydrogenation: Heating oil and motor fuels can be produced. Coal-derived motor fuel has a higher cost of 80 Pf/l as compared with petroleum-derived fuel. This means that even with financial aid by the state, hydrogenation will not be competitive for a long time to come. 4. Gasification: There are different fields of application. Syngas from brown coal has almost reached competitiveness; while SNG is still twice as expensive as natural gas and is not expected to become competitive within the next decade. Considerable improvements are expected of the HTR reactor, although the date of the commercial introduction is still uncertain. In view of the fact that coal will account for 30% of the future energy supply and in consideration of the enormous investments required, all economic, ecological, and technical aspects should be considered in order to optimize coal utilisation. Efficiency in utilisation must be assigned first priority in view of the increasing shortage of coal resources. (orig./EF)

  8. Low- and medium-Btu coal gasification processes

    Baker, N.R.; Blazek, C.F.; Tison, R.R.


    Coal gasifiers, for the production of low- and medium-Btu fuel gases, come in a wide variety of designs and capacities. For single gasifier vessels gas energy production rates range from about 1 to 18 billion Btu/day. The key characteristics of gasifiers that would be of importance for their application as an energy source in Integrated Community Energy Systems (ICES) are evaluated here. The types of gasifiers considered here are single- and two-stage, fixed-bed units; fluidized-bed units; and entrained-bed units, as producers of both low-Btu (less than 200 Btu/SCF and medium-Btu (200 to 400 Btu/SCF) gases. The gasifiers are discussed with respect to maximum and minimum capacity, the effect of feed coal parameters, product characteristics, thermal efficiency, environmental effects, operating and maintenance requirements, reliability, and cost. Some of the most recent development work in this area of coal conversion, and use of these gas products also is considered. Except in small plant installations (< 10/sup 9/ Btu/day) the annual operating costs for the various gasifier types are approximately the same. This is somewhat surprising in view of the personnel requirements, efficiencies, utility requirements, heating value of the product gas, and operating characteristics associated with each. Operating costs tend to increase with a power function exponent of 0.92 (i.e., a doubling in plant capacity increases the operating cost by about 1.9).

  9. Hazardous air pollutant testing at the LGTI coal gasification plant

    Wetherold, R.G.; Williams, W.A.; Maxwell, D.P.; Mann, R.M.


    A comprehensive hazardous air pollutant test program was conducted in November 1994 at the Louisiana Gasification Technology, Inc. (LGTI), plant in Plaquemine, Louisiana. This program was sponsored by DOE/PETC, the Electric Power Research Institute (EPRI), and Destec Energy. In May of 1995, additional testing of the hot syngas stream was conducted at the LGTI facility under this same program. DOE/METC provided additional technical support for the hot gas testing effort. In this paper, the sampling and analytical methods used during the November and May test program are summarized. The hot gas testing is described in greater detail. In particular, the hot gas sampling probe and probe insertion/withdrawal system are discussed. The sampling probe was designed to collect particulate and extract gas samples at process temperature and pressure. The design of the probe system is described, and the operating procedures are summarized. The operation of the probe during the testing is discussed, and photographs of the testing are provided. In addition to the summaries and descriptions of the test methodologies, selected preliminary emissions results of the November sampling are included in the paper.

  10. Aerosol emissions near a coal gasification plant in the Kosovo region, Yugoslavia

    Boueres, Luis Carlos S.; Patterson, Ronald K.


    Ambient aerosol samples from the region of Kosovo, Yugoslavia, were collected and analyzed for their elemental composition in order to determine the effect on ambient air quality of Lurgi coal gasification carried out there using low BTU lignite. Low-volume aerosol samples were used to collect air particulate matter during May of 1979. These samplers were deployed at five sites near the Kosovo industrial complex which is comprised of coal gasifier, a coal-fired power plant and a fertilizer plant which uses the waste products from the gasifier and power plant. A total of 126 impactor sets and 10 week-long "streaker" filters were analyzed by PIXE at FSU for 16-18 elements providing a data base of approximately 16 000 elemental concentrations. Preliminary results are reported here with emphasis on the following elements: Si, S, Ca, Fe, Zn and Pb.

  11. Aerosol emissions near a coal gasification plant in the Kosovo region, Yugoslavia

    Ambient aerosol samples from the region of Kosovo, Yugoslavia, were collected and analyzed for their elemental composition in order to determine the effect on ambient air quality of Lurgi coal gasification carried out there using low BTU lignite. Low-volume aerosol samples were used to collect air particulate matter during May of 1979. These samplers were deployed at five sites near the Kosovo industrial complex which is comprised of coal gasifier, a coal-fired power plant and a fertilizer plant which uses the waste products from the gasifier and power plant. A total of 126 impactor sets and 10 week-long streaker filters were analyzed by PIXE at FSU for 16-18 elements providing a data base of approximately 16000 elemental concentrations. Preliminary resuls are reported here with emphasis on the following elements: Si, S, Ca, Fe, Zn and Pb. (orig.)

  12. Thermodynamic analyses of a biomass-coal co-gasification power generation system.

    Yan, Linbo; Yue, Guangxi; He, Boshu


    A novel chemical looping power generation system is presented based on the biomass-coal co-gasification with steam. The effects of different key operation parameters including biomass mass fraction (Rb), steam to carbon mole ratio (Rsc), gasification temperature (Tg) and iron to fuel mole ratio (Rif) on the system performances like energy efficiency (ηe), total energy efficiency (ηte), exergy efficiency (ηex), total exergy efficiency (ηtex) and carbon capture rate (ηcc) are analyzed. A benchmark condition is set, under which ηte, ηtex and ηcc are found to be 39.9%, 37.6% and 96.0%, respectively. Furthermore, detailed energy Sankey diagram and exergy Grassmann diagram are drawn for the entire system operating under the benchmark condition. The energy and exergy efficiencies of the units composing the system are also predicted. PMID:26826573

  13. CO2 gasification of Powder River Basin coal catalyzed by a cost-effective and environmentally friendly iron catalyst

    Graphical abstract: SEM images of the char sample and the corresponding distribution of iron atom clusters from EDS. - Highlights: • Iron catalyst was reduced to metallic iron in coal pyrolysis. • SEM and EDS images shows the catalytic effect of iron on char gasification. • The shrinking core model is more suitable than the random pore model for this work. • The catalytic iron species were initially the metallic iron and FeO, and then changed to FeO and Fe3O4. - Abstract: CO2 gasification of a sub-bituminous Wyodak coal from the Powder River Basin (PRB) was conducted in a fixed-bed laboratory gasifier at atmospheric pressure with FeCO3 as a catalyst precursor. The effect of iron on the coal pyrolysis was evaluated by thermo-gravimetric analysis (TGA). Scanning electron microscopy (SEM) was employed to characterize the iron performance in the char gasification. The iron species and oxidation states during the coal gasification, characterized by X-ray diffraction (XRD) and Mössbauer spectroscopy, indicate a complex interaction between the reaction atmosphere and temperature, but generally proceed through reduction to FeO and metallic iron during pyrolysis, followed by subsequent reoxidation to Fe3O4 during gasification with CO2. The catalytic effect of iron was also quantitatively evaluated by kinetic analysis using shrinking core and random pore models, with the shrinking core model providing superior results. Results show that the apparent activation energy was 92.7 kJ/mol for the untreated coal, which decreased to 58.3 kJ/mol for the coal with 3 wt% Fe. FeCO3 was shown to have a significant catalytic effect on the Wyodak coal gasification with CO2


    陈恒宝; 周敏; 贺国章


    立足于煤泥的生产现状,利用热分析方法,研究了石圪台煤泥和浮选后的精细煤泥在不同的升温速率条件下的二氧化碳气化反应,得到了气化反应的TG/DTG曲线,并计算了气化转化率,考察了浮选对煤泥气化特性的影响.选用Coats-Redfern和Doyle近似式对气化过程进行动力学模拟,求解了气化反应活化能和指前因子,结果表明,煤泥和精细煤泥的活化能均随升温速率的增大而减小;在相同的升温速率下,两者的活化能相差不大;煤泥中含量较高的矿物质和灰分对气化具有催化作用.%Based on the present utilization situation of coal slime, this paper investigated the carbon dioxide gasification of Shigetai coal slime and fine coal slime after flotation at different heating rates using thermogravimetric analysis, and by TG/DTG curve of the gasification reaction, calculated the gasification conversion and examined the influence of flotation on coal slime gasification. Coats-Redfern and Doyle approximations were used to simulate the gasification behaviors for seeking activation energy and pre-exponential factor. The result showed that the values of the activation energy and the pre-exponential factor of coal slime and fine coal slime decrease with the increase of heating rate, while both are similar at same heating rates high levels of minerals and ash in coal slime have catalytic action on the gasification.

  15. Fluidized Bed Oxyfuel (CO2 + O2) Gasification of Coal-Oil and Coal-Water-Oil Slurries

    Svoboda, Karel; Pohořelý, Michael; Jeremiáš, Michal; Kameníková, Petra; Hartman, Miloslav; Skoblia, S.

    Bratislava: Slovak Society of Chemical Engineering, 2011 - (Markoš, J.), s. 259 ISBN 978-80-227-3503-2. [International Conference of Slovak Society of Chemical Engineering /38./. Tatranské Matliare (SK), 23.05.2011-27.05.2011] R&D Projects: GA MŠk 2B08048; GA MŠk 7C08034 Grant ostatní: RFCR(XE) CT-2010-00009 Institutional research plan: CEZ:AV0Z40720504 Keywords : fluidized bed * gasification * coal Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  16. Compartment modeling of coal gasification in an entrained flow gasifier: A study on the influence of operating conditions

    Highlights: • Gasification of Shenfu coal in an industrial Texaco gasifier for syngas production. • An equivalent compartment model is developed using Aspen Plus. • Effects of operating parameters on gasification performance indices are studied. • Choosing a reasonable ROC to enhance the gasification efficiency can be flexible. - Abstract: Coal gasifiers are core components of coal-based polygeneration systems for power and chemical production. To study the effects of operational parameters on the performance of entrained flow coal gasifiers, this paper presents an equivalent compartment model (CM) using the Aspen Plus process simulator. The CM blocking is established based on gasifier flow field analysis, using a number of compartments. A simple configuration of these compartments involving material recirculation should be able to simulate the main flow and provide the temperature and gas component distributions. The model predictions exhibit good agreement with industrial data in the model validation. The influences of the oxygen-to-carbon ratio (ROC) and the coal slurry concentration on the gasification performance are discussed. Within the calculation range, the increase in the coal slurry concentration enhances the yield of the effective compositions in product gas. For a given slurry concentration of 62%, the efficient gas yield is a maximum for ROC of 1.43 kg/kg, whereas the oxygen consumption is a minimum for ROC of 1.37 kg/kg. According to the intended final use, however, choosing a reasonable ROC to obtain a higher efficient syngas yield and lower oxygen consumption can be flexible

  17. An effect of Blade geometry on heat transfer performance in stirred vessel – coal water slurry system using coal gasification



    Full Text Available The effect of the geometrical parameter of blades on heat transfer co-efficient were experimentally studied for agitated vessels using coal slurry in coal gasification. The intensity of hear transfer during mixing of fluids depends on the type of the stirrer, the design of the vessel and conditions of the process. The type and size of the stirrer, as well as its location in the vessel, also affect the rate of hear transfer. In this study, the effect of some importantdesign parameter such as the type of stirrer, angle and shape of blades, number of blades and location of stirrer, etc., were investigated and optimized. Besides, the Taguchi method can successfully be applied to heat transfer investigation to save energy, time and material in experimentation.

  18. Circulating fluidized bed gasification of low rank coal: Influence of O2/C molar ratio on gasification performance and sulphur transformation

    Zhang, Haixia; Zhang, Yukui; Zhu, Zhiping; Lu, Qinggang


    To promote the utilization efficiency of coal resources, and to assist with the control of sulphur during gasification and/or downstream processes, it is essential to gain basic knowledge of sulphur transformation associated with gasification performance. In this research we investigated the influence of O2/C molar ratio both on gasification performance and sulphur transformation of a low rank coal, and the sulphur transformation mechanism was also discussed. Experiments were performed in a circulating fluidized bed gasifier with O2/C molar ratio ranging from 0.39 to 0.78 mol/mol. The results showed that increasing the O2/C molar ratio from 0.39 to 0.78 mol/mol can increase carbon conversion from 57.65% to 91.92%, and increase sulphur release ratio from 29.66% to 63.11%. The increase of O2/C molar ratio favors the formation of H2S, and also favors the retained sulphur transforming to more stable forms. Due to the reducing conditions of coal gasification, H2S is the main form of the released sulphur, which could be formed by decomposition of pyrite and by secondary reactions. Bottom char shows lower sulphur content than fly ash, and mainly exist as sulphates. X-ray photoelectron spectroscopy (XPS) measurements also show that the intensity of pyrite declines and the intensity of sulphates increases for fly ash and bottom char, and the change is more obvious for bottom char. During CFB gasification process, bigger char particles circulate in the system and have longer residence time for further reaction, which favors the release of sulphur species and can enhance the retained sulphur transforming to more stable forms.

  19. Nitrogen removal from coal gasification wastewater by activated carbon technologies combined with short-cut nitrogen removal process.

    Zhao, Qian; Han, Hongjun; Hou, Baolin; Zhuang, Haifeng; Jia, Shengyong; Fang, Fang


    A system combining granular activated carbon and powdered activated carbon technologies along with shortcut biological nitrogen removal (GAC-PACT-SBNR) was developed to enhance total nitrogen (TN) removal for anaerobically treated coal gasification wastewater with less need for external carbon resources. The TN removal efficiency in SBNR was significantly improved by introducing the effluent from the GAC process into SBNR during the anoxic stage, with removal percentage increasing from 43.8%-49.6% to 68.8%-75.8%. However, the TN removal rate decreased with the progressive deterioration of GAC adsorption. After adding activated sludge to the GAC compartment, the granular carbon had a longer service-life and the demand for external carbon resources became lower. Eventually, the TN removal rate in SBNR was almost constant at approx. 43.3%, as compared to approx. 20.0% before seeding with sludge. In addition, the production of some alkalinity during the denitrification resulted in a net savings in alkalinity requirements for the nitrification reaction and refractory chemical oxygen demand (COD) degradation by autotrophic bacteria in SBNR under oxic conditions. PACT showed excellent resilience to increasing organic loadings. The microbial community analysis revealed that the PACT had a greater variety of bacterial taxons and the dominant species associated with the three compartments were in good agreement with the removal of typical pollutants. The study demonstrated that pre-adsorption by the GAC-sludge process could be a technically and economically feasible method to enhance TN removal in coal gasification wastewater (CGW). PMID:25458677

  20. Management of coal waste by energy recovery: mild gasification/flash pyrolysis of coal preparation wastes. Quarterly report, October-December 1985

    Gillespie, B.L.


    Feedstock characterization is now complete. Two of the refuse feedstocks, the bituminous coal feedstock and the subbituminous coal feedstock, were obtained and prepared for use in the mild gasification unit (MGU). Construction continued on the mild gasification unit and is estimated to be 95% complete. Most of the major equipment for the MGU is in place and operational. The vacuum pump and hydraulic limit switches are the remaining items to be installed on the unit. The final test plan was prepared. The test plan includes 24 tests, six with subbituminous coal, seven with coal preparation waste, and eleven with bituminous coal. The tests are designed to measure the effects of feedstock, particle size, temperature, residence time, sweep gas, and solid additives on unit performance, product quantity, and product quality. The MGU has performed well during five tests with only minor problems dealing with condensation of the hydrocarbon gases.

  1. Steam gasification of coal cokes by internally circulating fluidized-bed reactor by concentrated Xe-light radiation for solar syngas production

    A laboratory-scale prototype windowed reactor using a fluidized bed of coal coke particles was tested for thermochemical gasification using concentrated Xe light radiation as an energy source. The fluidized-bed reactor, designed to be combined with a solar reflective tower or beam-down optics, is evaluated for steam gasification of coal coke according to gasification performance: CO, H2, and CO2 production rates; carbon conversion; light-to-chemical efficiency. Internal circulation of coal coke particles inside the reactor increases gasification performance, which is further enhanced by higher steam partial pressure of the inlet gas. - Highlights: • A reactor prototype was designed for solar steam gasification by beam-down optics. • Particle circulation homogenizes temperature distribution across all bed layers. • The reactor design of internal circulation improved gasification performances

  2. Design and materials of a large scale gas generator for the steam gasification of coal using nuclear heat

    For the gasification of coal, energy in the form of electricity and steam is needed as well as process heat. In conventional gasification processes, e.g., Lurgi, Winkler, and Koppers-Totzek, this energy is generated by the combustion of about 40 - 50% of the feed coal. An equivalent amount of coal can consequently be saved or converted into gas if electricity, steam, and especially process heat, are made available from a high-temperature nuclear reactor (HTR). The nuclear heat from the HTR is used directly as process heat. In view of the almost double-specific gas yield compared with conventional gasification the approach here has three major advantages: 1. saving of available coal reserves; 2. reduction of specific coal emissions; 3. lower gas production costs compared to conventional gasification. Helium is used as heat carrier in the primary HTR circuit and heated up to 9500C. The heat is transferred via a heat exchanger to a secondary circuit which also uses helium as the operating medium. This paper describes function and design of the gas generator, its main components, the materials especially selected for the high temperature heat exchanger and the experience with a pilot plant gasifier

  3. Effect of Gasifying Medium on the Coal Chemical Looping Gasification with CaSO4 as Oxygen Carrier☆

    Yongzhuo Liu; Weihua Jia; Qingjie Guo; Hojung Ryu


    The chemical looping gasification uses an oxygen carrier for solid fuel gasification by supplying insufficient lattice oxygen. The effect of gasifying medium on the coal chemical looping gasification with CaSO4 as oxygen carrier is investigated in this paper. The thermodynamical analysis indicates that the addition of steam and CO2 into the system can reduce the reaction temperature, at which the concentration of syngas reaches its maximum value. Experimental result in thermogravimetric analyzer and a fixed-bed reactor shows that the mixture sample goes through three stages, drying stage, pyrolysis stage and chemical looping gasification stage, with the temper-ature for three different gaseous media. The peak fitting and isoconversional methods are used to determine the reaction mechanism of the complex reactions in the chemical looping gasification process. It demonstrates that the gasifying medium (steam or CO2) boosts the chemical looping process by reducing the activation energy in the overall reaction and gasification reactions of coal char. However, the mechanism using steam as the gasifying medium differs from that using CO2. With steam as the gasifying medium, parallel reactions occur in the begin-ning stage, followed by a limiting stage shifting from a kinetic to a diffusion regime. It is opposite to the reaction mechanism with CO2 as the gasifying medium.

  4. Coal and char properties in high temperature entrained flow gasification

    With the objective to measure coal conversion at realistic operation conditions the Pressurised High Temperature Entrained Flow Reactor (PiTER) is developed. The pyrolysis of Rhenish lignite is studied at temperatures up to 1600 °C and pressures up to 2.5 MPa. At longer residence time (above 1.5 s) volatile yield is 68 wt% and independent of temperature and pressure. Char samples are extracted from the hot reaction zone and their reactivity is analysed by weight loss in TGA experiments at defined conditions. Furthermore, specific char surface area is measured. At 1200 °C the intrinsic reactivity of char decreases by a factor of almost 7 from 0.5 s to 2 s residence time, but surface area (approximately 500 m2/g) is hardly affected. At 1400 °C and 1600 °C, the intrinsic reactivity also decreases, but simultaneously the surface area is reduced to below 300 m2/g. The difference in deactivation can only be explained by two different mechanisms: (i) experiments at 1200 °C are below the ash fusion temperature and graphitisation at the char surface may lead to a reorganisation of carbon atoms; (ii) above the ash fusion temperature, the melting of mineral matter additionally blocks the micropore structure and results in a loss of specific surface area. -- Highlights: ► Development of a novel pilot scale entrained flow research reactor. ► Pyrolysis at up to 1600 °C and up to 2.5 MPa under entrained flow conditions. ► Surface area of char significantly decreases above the ash melting temperature. ► Intrinsic reactivity of char is dependent on heat treatment severity. ► Thermal annealing affects char reactivity, even at short residence time.

  5. Molten salt coal gasification process development unit. Phase 1. Volume 1. PDU operations. Final report

    Kohl, A.L.


    This report summarizes the results of a test program conducted on the Molten Salt Coal Gasification Process, which included the design, construction, and operation of a Process Development Unit. In this process, coal is gasified by contacting it with air in a turbulent pool of molten sodium carbonate. Sulfur and ash are retained in the melt, and a small stream is continuously removed from the gasifier for regeneration of sodium carbonate, removal of sulfur, and disposal of the ash. The process can handle a wide variety of feed materials, including highly caking coals, and produces a gas relatively free from tars and other impurities. The gasification step is carried out at approximately 1800/sup 0/F. The PDU was designed to process 1 ton per hour of coal at pressures up to 20 atm. It is a completely integrated facility including systems for feeding solids to the gasifier, regenerating sodium carbonate for reuse, and removing sulfur and ash in forms suitable for disposal. Five extended test runs were made. The observed product gas composition was quite close to that predicted on the basis of earlier small-scale tests and thermodynamic considerations. All plant systems were operated in an integrated manner during one of the runs. The principal problem encountered during the five test runs was maintaining a continuous flow of melt from the gasifier to the quench tank. Test data and discussions regarding plant equipment and process performance are presented. The program also included a commercial plant study which showed the process to be attractive for use in a combined-cycle, electric power plant. The report is presented in two volumes, Volume 1, PDU Operations, and Volume 2, Commercial Plant Study.

  6. Large pilot plant alternatives for scaleup of the catalytic coal gasification process. Final report

    Cohen, S.J.


    This is the final report for US Department of Energy Contract No. EX-76-C-01-2480, Scaleup Requirements of the Exxon Catalyzed Coal Gasification Process. The objective was to develop the information necessary to determine if an existing DOE large pilot plant could be used to obtain the scaleup data necessary to design and construct a Catalytic Coal Gasification (CCG) pioneer plant with acceptable risk. A pioneer plant is a stand-alone facility, whose primary function is to operate as a profitable commercial venture. The pioneer plant would contain all equipment of full commercial size, as defined by the requirements for an optimum-sized commercial plant. However, the pioneer plant could have a single train of equipment in some or all of the plant sections. The three tasks contained in this contract are discussed: study design and cost estimate for a grass-roots large pilot plant; selection of the preferred existing pilot plant; and study design and cost estimate for revamp of the preferred existing pilot plant.

  7. DOE Coal Gasification Multi-Test Facility: fossil fuel processing technical/professional services

    Hefferan, J.K.; Lee, G.Y.; Boesch, L.P.; James, R.B.; Rode, R.R.; Walters, A.B.


    A conceptual design, including process descriptions, heat and material balances, process flow diagrams, utility requirements, schedule, capital and operating cost estimate, and alternative design considerations, is presented for the DOE Coal Gasification Multi-Test Facility (GMTF). The GMTF, an engineering scale facility, is to provide a complete plant into which different types of gasifiers and conversion/synthesis equipment can be readily integrated for testing in an operational environment at relatively low cost. The design allows for operation of several gasifiers simultaneously at a total coal throughput of 2500 tons/day; individual gasifiers operate at up to 1200 tons/day and 600 psig using air or oxygen. Ten different test gasifiers can be in place at the facility, but only three can be operated at one time. The GMTF can produce a spectrum of saleable products, including low Btu, synthesis and pipeline gases, hydrogen (for fuel cells or hydrogasification), methanol, gasoline, diesel and fuel oils, organic chemicals, and electrical power (potentially). In 1979 dollars, the base facility requires a $288 million capital investment for common-use units, $193 million for four gasification units and four synthesis units, and $305 million for six years of operation. Critical reviews of detailed vendor designs are appended for a methanol synthesis unit, three entrained flow gasifiers, a fluidized bed gasifier, and a hydrogasifier/slag-bath gasifier.

  8. Formation of hydrogen cyanide and ammonia during the gasification of sewage sludge and bituminous coal

    N. Paterson; Y. Zhuo; D. Dugwell; R. Kandiyoti [Imperial College London, London (United Kingdom). Department of Chemical Engineering


    HCN and NH{sub 3} released during the gasification of sewage sludge have been measured during a program of tests with a laboratory-scale spouted-bed gasifier. The data have been compared with results from gasification tests with coal. The effect of altering the bed temperature has been investigated, and the results have been related to reactions involving gaseous N species known to occur in the gasifier. The effect of steam addition on the HCN release has been examined. It has been found that the HCN concentrations in the exit gas increase with the operating temperature, which is thought to indicate increased formation as a primary product of the decomposition of the fuel-N compounds. Increasing the height of the char bed caused a significant reduction in the HCN concentration at the exit, as this promoted the decomposition of HCN to NH{sub 3}. Steam addition caused a rise in the HCN concentration during tests with sewage sludge and a similar effect had previously been reported on the NH{sub 3} concentration during tests with coal. The NH{sub 3} concentration decreased with increasing temperature, and this is thought to reflect the increased rate of the equilibration of NH{sub 3} in the gas phase to form N{sub 2} and H{sub 2}. 18 refs., 4 figs., 5 tabs.

  9. A study of toxic emissions from a coal-fired gasification plant. Final report



    Under the Fine Particulate Control/Air Toxics Program, the US Department of Energy (DOE) has been performing comprehensive assessments of toxic substance emissions from coal-fired electric utility units. An objective of this program is to provide information to the US Environmental Protection Agency (EPA) for use in evaluating hazardous air pollutant emissions as required by the Clean Air Act Amendments (CAAA) of 1990. The Electric Power Research Institute (EPRI) has also performed comprehensive assessments of emissions from many power plants and provided the information to the EPA. The DOE program was implemented in two. Phase 1 involved the characterization of eight utility units, with options to sample additional units in Phase 2. Radian was one of five contractors selected to perform these toxic emission assessments.Radian`s Phase 1 test site was at southern Company Service`s Plant Yates, Unit 1, which, as part of the DOE`s Clean Coal Technology Program, was demonstrating the CT-121 flue gas desulfurization technology. A commercial-scale prototype integrated gasification-combined cycle (IGCC) power plant was selected by DOE for Phase 2 testing. Funding for the Phase 2 effort was provided by DOE, with assistance from EPRI and the host site, the Louisiana Gasification Technology, Inc. (LGTI) project This document presents the results of that effort.

  10. Sulfidation-resistant alloy for coal gasification service. Quarterly report, September 1--November 30, 1977

    An Fe-18Cr-5Al-1Mo-1Hf alloy has been tested in synthetic coal gasification atmospheres at 500 and 1000 psi pressure. Resistance to attack is similar to that observed at atmospheric pressure. Tests also have been made at high pressure in a low P/sub O2/-high P/sub S2/ atmosphere representative of low Btu gasification. The alloy did not resist attack under these conditions and has a transition to non-protective behavior with decreasing P/sub O2/ and/or increasing P/sub S2/. A molybdenum alloy (TZM-Mo) is being screened for sulfidation resistance in coal gasification atmospheres. Initial tests at 18000F in the DOE/MPC gas mixture show a parabolic rate behavior with negligible attack. Extrapolation of the data indicates a potential loss of 0.2 mil in one year, with 1% H2S in the gas. Samples will be exposed to a cumulative time of 4000 hr to obtain more accurate rate data. Impact tests indicate that Al and Si lower the notched impact toughness and raise the ductile to brittle transition temperature of Fe-Cr alloys with 17-19Cr. The addition of 1 to 2% Mo slightly improves impact behavior. An Fe-18Cr-5Al-1Mo-1Hf alloy is concluded to have the best combination of corrosion resistance and mechanical properties. This composition and an upper limit composition of 19Cr-6Al-2Mo-1Hf have been selected for the final Phase III evaluation. Two 50-lb ingots of each composition have been vacuum induction melted and cast successfully