WorldWideScience

Sample records for bed partial gasification

  1. DEVELOPMENT OF PRESSURIZED CIRCULATING FLUIDIZED BED PARTIAL GASIFICATION MODULE (PGM)

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2002-03-29

    Foster Wheeler Development Corporation is working under DOE contract No. DE-FC26-00NT40972 to develop a partial gasification module (PGM) that represents a critical element of several potential coal-fired Vision 21 plants. When utilized for electrical power generation, these plants will operate with efficiencies greater than 60% while producing near zero emissions of traditional stack gas pollutants. The new process partially gasifies coal at elevated pressure producing a coal-derived syngas and a char residue. The syngas can be used to fuel the most advanced power producing equipment such as solid oxide fuel cells or gas turbines or processed to produce clean liquid fuels or chemicals for industrial users. The char residue is not wasted; it can also be used to generate electricity by fueling boilers that drive the most advanced ultra-supercritical pressure steam turbines. The unique aspect of the process is that it utilizes a pressurized circulating fluidized bed partial gasifier and does not attempt to consume the coal in a single step. To convert all the coal to syngas in a single step requires extremely high temperatures ({approx}2500 to 2800 F) that melt and vaporize the coal and essentially drive all coal ash contaminants into the syngas. Since these contaminants can be corrosive to power generating equipment, the syngas must be cooled to near room temperature to enable a series of chemical processes to clean the syngas. Foster Wheeler's process operates at much lower temperatures that control/minimize the release of contaminants; this eliminates/minimizes the need for the expensive, complicated syngas heat exchangers and chemical cleanup systems typical of high temperature gasification. By performing the gasification in a circulating bed, a significant amount of syngas can still be produced despite the reduced temperature and the circulating bed allows easy scale up to large size plants. Rather than air, it can also operate with oxygen to facilitate

  2. DEVELOPMENT OF PRESSURIZED CIRCULATING FLUIDIZED BED PARTIAL GASIFICATION MODULE (PGM)

    Energy Technology Data Exchange (ETDEWEB)

    Archie Robertson

    2003-07-23

    Foster Wheeler Power Group, Inc. is working under US Department of Energy contract No. DE-FC26-00NT40972 to develop a partial gasification module (PGM) that represents a critical element of several potential coal-fired Vision 21 plants. When utilized for electrical power generation, these plants will operate with efficiencies greater than 60% and produce near zero emissions of traditional stack gas pollutants. The new process partially gasifies coal at elevated pressure producing a coal-derived syngas and a char residue. The syngas can be used to fuel the most advanced power producing equipment such as solid oxide fuel cells or gas turbines, or processed to produce clean liquid fuels or chemicals for industrial users. The char residue is not wasted; it can also be used to generate electricity by fueling boilers that drive the most advanced ultra-supercritical pressure steam turbines. The amount of syngas and char produced by the PGM can be tailored to fit the production objectives of the overall plant, i.e., power generation, clean liquid fuel production, chemicals production, etc. Hence, PGM is a robust building bock that offers all the advantages of coal gasification but in a more user-friendly form; it is also fuel flexible in that it can use alternative fuels such as biomass, sewerage sludge, etc. This report describes the work performed during the April 1--June 30, 2003 time period.

  3. DEVELOPMENT OF PRESSURIZED CIRCULATING FLUDIZED BED PARTIAL GASIFICATION MODULE (PGM)

    Energy Technology Data Exchange (ETDEWEB)

    Archie Robertson

    2002-07-10

    Foster Wheeler Power Group, Inc. is working under US Department of Energy contract No. DE-FC26-00NT40972 to develop a partial gasification module (PGM) that represents a critical element of several potential coal-fired Vision 21 plants. When utilized for electrical power generation, these plants will operate with efficiencies greater than 60% and produce near zero emissions of traditional stack gas pollutants. The new process partially gasifies coal at elevated pressure producing a coal-derived syngas and a char residue. The syngas can be used to fuel the most advanced power producing equipment such as solid oxide fuel cells or gas turbines, or processed to produce clean liquid fuels or chemicals for industrial users. The char residue is not wasted; it can also be used to generate electricity by fueling boilers that drive the most advanced ultra-supercritical pressure steam turbines. The amount of syngas and char produced by the PGM can be tailored to fit the production objectives of the overall plant, i.e., power generation, clean liquid fuel production, chemicals production, etc. Hence, PGM is a robust building bock that offers all the advantages of coal gasification but in a more user-friendly form; it is also fuel flexible in that it can use alternative fuels such as biomass, sewerage sludge, etc. This report describes the work performed during the April 1--June 30, 2002 time period.

  4. DEVELOPMENT OF PRESSURIZED CIRCULATING FLUIDIZED BED PARTIAL GASIFICATION MODULE (PGM)

    Energy Technology Data Exchange (ETDEWEB)

    Archie Robertson

    2003-10-29

    Foster Wheeler Power Group, Inc. is working under US Department of Energy contract No. DE-FC26-00NT40972 to develop a partial gasification module (PGM) that represents a critical element of several potential coal-fired Vision 21 plants. When utilized for electrical power generation, these plants will operate with efficiencies greater than 60% and produce near zero emissions of traditional stack gas pollutants. The new process partially gasifies coal at elevated pressure producing a coal-derived syngas and a char residue. The syngas can be used to fuel the most advanced power producing equipment such as solid oxide fuel cells or gas turbines, or processed to produce clean liquid fuels or chemicals for industrial users. The char residue is not wasted; it can also be used to generate electricity by fueling boilers that drive the most advanced ultra-supercritical pressure steam turbines. The amount of syngas and char produced by the PGM can be tailored to fit the production objectives of the overall plant, i.e., power generation, clean liquid fuel production, chemicals production, etc. Hence, PGM is a robust building bock that offers all the advantages of coal gasification but in a more user-friendly form; it is also fuel flexible in that it can use alternative fuels such as biomass, sewerage sludge, etc. This report describes the work performed during the July 1--September 30, 2003 time period.

  5. Development of Pressurized Circulating Fluidized Bed Partial Gasification Module (PGM)

    Energy Technology Data Exchange (ETDEWEB)

    A. Robertson

    2002-09-30

    Foster Wheeler Power Group, Inc. is working under US Department of Energy contract No. DE-FC26-00NT40972 to develop a partial gasification module (PGM) that represents a critical element of several potential coal-fired Vision 21 plants. When utilized for electrical power generation, these plants will operate with efficiencies greater than 60% and produce near zero emissions of traditional stack gas pollutants. The new process partially gasifies coal at elevated pressure producing a coal-derived syngas and a char residue. The syngas can be used to fuel the most advanced power producing equipment such as solid oxide fuel cells or gas turbines, or processed to produce clean liquid fuels or chemicals for industrial users. The char residue is not wasted; it can also be used to generate electricity by fueling boilers that drive the most advanced ultra-supercritical pressure steam turbines. The amount of syngas and char produced by the PGM can be tailored to fit the production objectives of the overall plant, i.e., power generation, clean liquid fuel production, chemicals production, etc. Hence, PGM is a robust building bock that offers all the advantages of coal gasification but in a more user-friendly form; it is also fuel flexible in that it can use alternative fuels such as biomass, sewerage sludge, etc. This report describes the work performed during the July 1-September 30, 2002 time period.

  6. DEVELOPMENT OF PRESSURIZED CIRCULATING FLUIDIZED BED PARTIAL GASIFICATION MODULE (PGM)

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2003-01-30

    Foster Wheeler Power Group, Inc. is working under US Department of Energy contract No. DE-FC26-00NT40972 to develop a partial gasification module (PGM) that represents a critical element of several potential coal-fired Vision 21 plants. When utilized for electrical power generation, these plants will operate with efficiencies greater than 60% and produce near zero emissions of traditional stack gas pollutants. The new process partially gasifies coal at elevated pressure producing a coal-derived syngas and a char residue. The syngas can be used to fuel the most advanced power producing equipment such as solid oxide fuel cells or gas turbines, or processed to produce clean liquid fuels or chemicals for industrial users. The char residue is not wasted; it can also be used to generate electricity by fueling boilers that drive the most advanced ultra-supercritical pressure steam turbines. The amount of syngas and char produced by the PGM can be tailored to fit the production objectives of the overall plant, i.e., power generation, clean liquid fuel production, chemicals production, etc. Hence, PGM is a robust building bock that offers all the advantages of coal gasification but in a more user-friendly form; it is also fuel flexible in that it can use alternative fuels such as biomass, sewerage sludge, etc. This report describes the work performed during the October 1--December 31, 2002 time period.

  7. DEVELOPMENT OF PRESSURIZED CIRCULATIONG FLUIDIZED BED PARTIAL GASIFICATION MODULE(PGM)

    Energy Technology Data Exchange (ETDEWEB)

    Archie Robertson

    2003-04-17

    Foster Wheeler Power Group, Inc. is working under US Department of Energy contract No. DE-FC26-00NT40972 to develop a partial gasification module (PGM) that represents a critical element of several potential coal-fired Vision 21 plants. When utilized for electrical power generation, these plants will operate with efficiencies greater than 60% and produce near zero emissions of traditional stack gas pollutants. The new process partially gasifies coal at elevated pressure producing a coal-derived syngas and a char residue. The syngas can be used to fuel the most advanced power producing equipment such as solid oxide fuel cells or gas turbines, or processed to produce clean liquid fuels or chemicals for industrial users. The char residue is not wasted; it can also be used to generate electricity by fueling boilers that drive the most advanced ultra-supercritical pressure steam turbines. The amount of syngas and char produced by the PGM can be tailored to fit the production objectives of the overall plant, i.e., power generation, clean liquid fuel production, chemicals production, etc. Hence, PGM is a robust building block that offers all the advantages of coal gasification but in a more user-friendly form; it is also fuel flexible in that it can use alternative fuels such as biomass, sewerage sludge, etc. This report describes the work performed during the January 1--March 31, 2003 time period.

  8. Fluidised-bed combustion of gasification residue

    Energy Technology Data Exchange (ETDEWEB)

    Korpela, T.; Kudjoi, A.; Hippinen, I.; Heinolainen, A.; Suominen, M.; Lu Yong [Helsinki Univ. of Technology (Finland). Lab of Energy Economics and Power Plant Engineering

    1996-12-01

    Partial gasification processes have been presented as possibilities for future power production. In the processes, the solid materials removed from a gasifier (i.e. fly ash and bed material) contain unburnt fuel and the fuel conversion is increased by burning this gasification residue either in an atmospheric or a pressurised fluidised-bed. In this project, which is a part of European JOULE 2 EXTENSION research programme, the main research objectives are the behaviour of calcium and sulphur compounds in solids and the emissions of sulphur dioxide and nitrogen oxides (NO{sub x} and N{sub 2}O) in pressurised fluidised-bed combustion of gasification residues. (author)

  9. Fixed bed gasification of solid biomass fuels

    Energy Technology Data Exchange (ETDEWEB)

    Haavisto, I. [Condens Oy, Haemeenlinna (Finland)

    1996-12-31

    Fixed bed biomass gasifiers are feasible in the effect range of 100 kW -10 MW. Co-current gasification is available only up to 1 MW for technical reasons. Counter-current gasifiers have been used in Finland and Sweden for 10 years in gasification heating plants, which are a combination of a gasifier and an oil boiler. The plants have proved to have a wide control range, flexible and uncomplicated unmanned operation and an excellent reliability. Counter-current gasifiers can be applied for new heating plants or for converting existing oil and natural gas boilers into using solid fuels. There is a new process development underway, aiming at motor use of the producer gas. The development work involves a new, more flexible cocurrent gasifier and a cleaning step for the counter-current producer gas. (orig.)

  10. Biofluid process: fluidised-bed gasification of biomass

    Energy Technology Data Exchange (ETDEWEB)

    Dittrich, A. [ATEKO a.s., Hradec Kralove (Czech Republic)

    1996-12-31

    Fluidised-bed gasification of biomass was developed by ATEKO by using long-term experience from coal gasification. An experimental unit was built and a number of tests, first with sawdust gasification, were carried out. A gas combustion engine combined with a power generator was installed and operated in power production. (orig.)

  11. Modeling biomass gasification in circulating fluidized beds

    Science.gov (United States)

    Miao, Qi

    In this thesis, the modeling of biomass gasification in circulating fluidized beds was studied. The hydrodynamics of a circulating fluidized bed operating on biomass particles were first investigated, both experimentally and numerically. Then a comprehensive mathematical model was presented to predict the overall performance of a 1.2 MWe biomass gasification and power generation plant. A sensitivity analysis was conducted to test its response to several gasifier operating conditions. The model was validated using the experimental results obtained from the plant and two other circulating fluidized bed biomass gasifiers (CFBBGs). Finally, an ASPEN PLUS simulation model of biomass gasification was presented based on minimization of the Gibbs free energy of the reaction system at chemical equilibrium. Hydrodynamics plays a crucial role in defining the performance of gas-solid circulating fluidized beds (CFBs). A 2-dimensional mathematical model was developed considering the hydrodynamic behavior of CFB gasifiers. In the modeling, the CFB riser was divided into two regions: a dense region at the bottom and a dilute region at the top of the riser. Kunii and Levenspiel (1991)'s model was adopted to express the vertical solids distribution with some other assumptions. Radial distributions of bed voidage were taken into account in the upper zone by using Zhang et al. (1991)'s correlation. For model validation purposes, a cold model CFB was employed, in which sawdust was transported with air as the fluidizing agent. A comprehensive mathematical model was developed to predict the overall performance of a 1.2 MWe biomass gasification and power generation demonstration plant in China. Hydrodynamics as well as chemical reaction kinetics were considered. The fluidized bed riser was divided into two distinct sections: (a) a dense region at the bottom of the bed where biomass undergoes mainly heterogeneous reactions and (b) a dilute region at the top where most of homogeneous

  12. Gasification of wood in a fluidized bed reactor

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, L.C. de; Marti, T.; Frankenhaeuser, M. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-06-01

    A first series of gasification experiments with our fluidized bed gasifier was performed using clean sawdust as fuel. The installation and the analytical systems were tested in a parametric study in which gasification temperature and equivalence ratio were varied. The data acquired will serve to establish the differences between the gasification of clean wood and the gasification of Altholz (scrapwood) and wood/plastics mixtures. (author) 1 fig., 3 tabs., 5 refs.

  13. Lignite air-steam gasification in the fluidized bed of iron-containing slag catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetsov, B.N.; Shchipko, M.L.; Golovin, Yu. [Inst. of Chemistry of Natural Organic Materials, Academgorodok, Krasnoyarsk (Russian Federation)

    1995-12-01

    The influence of fluidized bed of iron-containing slag particles on air-steam gasification of powdered Kansk-Achinsk lignite in entrained flow was studied in pilot installation with productivity about 60 kg per hour. Slag of Martin process and boiler slag were used as catalytic active materials until their complete mechanical attrition. Two following methods of catalytic gasification of lignite were compared: the partial gasification in stationary fluidized bed of slag particles with degree of fuel conversion 40-70% and complete gasification in circulating bed of slag particles. In the first case only the most reactive part of fuel is gasified with the simultaneously formation of porous carbon residue with good sorption ability. It was found the catalytic fluidized bed improves heat transfer from combustion to reduction zone of gas-generator and increases the rate of fuel conversion at the temperature range 900-1000{degrees}C. At these temperatures the degree of conversion is depended considerably on the duration time of fuel particles in the catalytic fluidized bed. The influence of catalytic fluidized bed height and velocity of reaction mixture on the temperature profiles in the gas-generator was studied. The optimal relationship was found between the fluidized bed height and velocity of flow which makes possible to produce the gas with higher calorific value at maximum degree of fuel conversion.

  14. Gasification of sawdust in pressurised internally circulating fluidized bed

    Energy Technology Data Exchange (ETDEWEB)

    Maartensson, R.; Lindblom, M. [Lund Univ. (Sweden). Dept. of Chemical Engineering

    1996-12-31

    A test plant for pressurised gasification of biofuels in a internally circulating fluidized bed has been built at the department of Chemical Engineering II at the University of Lund. The design performance is set to maximum 20 bar and 1 050 deg C at a thermal input of 100 kW or a maximum fuel input of 18 kg/in. The primary task is to study pressurised gasification of biofuels in relation to process requirements of the IGCC concept (integrated gasification combined cycle processes), which includes studies in different areas of hot gas clean-up in reducing atmosphere for gas turbine applications. (orig.)

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

    International Nuclear Information System (INIS)

    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.)

  16. Autothermal gasification of low-grade fuels in fluidized bed

    Science.gov (United States)

    Belyaev, A. A.

    2009-01-01

    Autothermal gasification of high-ash floatation wastes of Grade Zh Kuzbass coal and low-ash fuel in a suspended-spouted (fluidized) bed at atmospheric pressure is investigated, and a comparison is presented of experimental results that indicate that the ash content of fuels has only slight influence on the generator gas heating value.

  17. Autothermal gasification of low-grade fuels in fluidized bed

    Energy Technology Data Exchange (ETDEWEB)

    A.A. Belyaev [Scientific Center for Comprehensive Processing of Solid Combustible Minerals (IGI), Moscow (Russian Federation). Institute of Combustible Minerals Federal State Unitary Enterprise

    2009-01-15

    Autothermal gasification of high-ash flotation wastes of Grade Zh Kuzbass coal and low-ash fuel in a suspended-spouted (fluidized) bed at atmospheric pressure is investigated, and a comparison is presented of experimental results that indicate that the ash content of fuels has only slight influence on the generator gas heating value.

  18. Gasification of Coal and PET in Fluidized Bed Reactor

    Czech Academy of Sciences Publication Activity Database

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

    2006-01-01

    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

  19. Defluidisation of fluidised beds during gasification of biomass

    International Nuclear Information System (INIS)

    Defluidisation and agglomeration during fluidised bed gasification of biomass is analysed and discussed. It is argued that the agglomeration and defluidisation processes, in principle, closely resemble those that determine the behaviour of glass during glass processing. Crucial properties for working with glass melts are the viscosity, stickiness, surface tension, etc. It is, however, (very) difficult to theoretically quantify these properties through thermodynamics or other theoretical means. Hence it will be problematic to theoretically predict agglomeration and defluidisation. Models for predicting defluidisation must therefore probably be of an empirical nature. As a consequence of this, a number of fluidised bed gasification tests were empirically analysed with respect to defluidisation. In total 145 tests were evaluated; of these 51 defluidised or exhibited some kind of bed disturbance. A number of fuels and bed materials were included in the analysis using a multivariate statistical approach. Based on the analysis an empirical regression equation for predicting the defluidisation temperature during fluidised bed gasification is suggested. -- Highlights: → An empirical regression equation for predicting the defluidisation temperature is suggested. → Alkali and pressure lowers the defluidisation temperatures, whilst Ca and Mg has the opposite effect. → Magnesite as bed material relative to quartz or olivine sand increase defluidisation temperatures with more than 100 oC.

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

    International Nuclear Information System (INIS)

    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

  1. Bubbling fluidised bed gasification of wheat straw-gasifier performance using mullite as bed material

    OpenAIRE

    Mac an Bhaird, Seán T.; Hemmingway, Phil; Walsh, Eilín; McDonnell, Kevin; et al.

    2015-01-01

    The adoption of wheat straw as a fuel for gasification processes has been hindered due to a lack of experience and its propensity to cause bed agglomeration in fluidised bed gasifiers. In this study wheat straw was gasified in a small scale, air blown bubbling fluidised bed using mullite as bed material. The gasifier was successfully operated and isothermal bed conditions maintained at temperatures up to 750 ◦C. Below this temperature, the gasifier was operated at equivalence ratios from 0.1 ...

  2. An Experimental and Numerical Investigation of Fluidized Bed Gasification of Solid Waste

    OpenAIRE

    Sharmina Begum; Mohammad G. Rasul; Delwar Akbar; David Cork

    2013-01-01

    Gasification is a thermo-chemical process to convert carbon-based products such as biomass and coal into a gas mixture known as synthetic gas or syngas. Various types of gasification methods exist, and fluidized bed gasification is one of them which is considered more efficient than others as fuel is fluidized in oxygen, steam or air. This paper presents an experimental and numerical investigation of fluidized bed gasification of solid waste (SW) (wood). The experimental measurement of syngas...

  3. Analysis of bed agglomeration during gasification of wheat straw in a bubbling fluidised bed gasifier using mullite as bed material

    OpenAIRE

    Mac an Bhaird, Seán T.; Walsh, Eilín; Hemmingway, Phil; McDonnell, Kevin; et al.

    2014-01-01

    The quantity and composition of the ash content of straw poses technical challenges to its thermal conversion and have been widely reported to cause severe ash sintering and bed agglomeration during fluidised bed gasification. Literature indicates that a combination of reactor design and bed material measures is required to avoid defluidisation at temperatures above 800 °C. Using scanning electron microscopy and energy dispersive X-ray spectroscopy this study investigated the initial agglomer...

  4. The influence of partial oxidation mechanisms on tar destruction in TwoStage biomass gasification

    DEFF Research Database (Denmark)

    Ahrenfeldt, Jesper; Egsgaard, Helge; Stelte, Wolfgang;

    2013-01-01

    TwoStage gasification of biomass results in almost tar free producer gas suitable for multiple end-use purposes. In the present study, it is investigated to what extent the partial oxidation process of the pyrolysis gas from the first stage is involved in direct and in-direct tar destruction and...... conversion. The study identifies the following major impact factors regarding tar content in the producer gas: oxidation temperature, excess air ratio and biomass moisture content. In a experimental setup, wood pellets were pyrolyzed and the resulting pyrolysis gas was transferred in a heated partial...... resulting PAH tar compounds are readily converted in the subsequent char-bed of the TwoStage gasification process and the partial oxidation process thus contributes directly as well as in-directly to the overall tar destruction. A high temperature and excess air ratios contribute positively to the direct...

  5. Attempts on cardoon gasification in two different circulating fluidized beds

    Directory of Open Access Journals (Sweden)

    Chr. Christodoulou

    2014-11-01

    Full Text Available Few tests have been carried out in order to evaluate the use of cardoon in gasification and combustion applications most of the researchers dealt with agglomeration problems. The aim of this work is to deal with the agglomeration problem and to present a solution for the utilization of this biofuel at a near industrial application scale. For this reason, two experiments were conducted, one in TU Delft and one in Centre for Research and Technology Hellas (CERTH, using fuel cardoon and 50% w/w cardoon blended with 50% w/w giant reed respectively. Both experimental campaigns were carried out in similar atmospheric circulating fluidized bed gasifiers. Apart from the feedstock, the other differences were the gasification medium and the bed material used in each trial. The oxidizing agent at TUD׳s run was O2/steam, whereas CERTH׳s tests used air. When experiments with the cardoon 50% w/w–giant reed 50% w/w blend were performed no agglomeration problems were presented. Consequently, gasification could be achieved in higher temperature than that of pure cardoon which led to the reduction of tar concentration.

  6. Gasification of solid waste — potential and application of co-current moving bed gasifiers

    NARCIS (Netherlands)

    Groeneveld, M.J.; Swaaij, van W.P.M.

    1979-01-01

    A review is given of gasification processes for solid fuels with special emphasis on waste gasification. Although the co-current moving bed gasifier has not been under consideration for a long time, it offers interesting possibilities for waste gasification. Some operational data are given. Two pote

  7. Performance analysis of RDF gasification in a two stage fluidized bed-plasma process.

    Science.gov (United States)

    Materazzi, M; Lettieri, P; Taylor, R; Chapman, C

    2016-01-01

    The major technical problems faced by stand-alone fluidized bed gasifiers (FBG) for waste-to gas applications are intrinsically related to the composition and physical properties of waste materials, such as RDF. The high quantity of ash and volatile material in RDF can provide a decrease in thermal output, create high ash clinkering, and increase emission of tars and CO2, thus affecting the operability for clean syngas generation at industrial scale. By contrast, a two-stage process which separates primary gasification and selective tar and ash conversion would be inherently more forgiving and stable. This can be achieved with the use of a separate plasma converter, which has been successfully used in conjunction with conventional thermal treatment units, for the ability to 'polish' the producer gas by organic contaminants and collect the inorganic fraction in a molten (and inert) state. This research focused on the performance analysis of a two-stage fluid bed gasification-plasma process to transform solid waste into clean syngas. Thermodynamic assessment using the two-stage equilibrium method was carried out to determine optimum conditions for the gasification of RDF and to understand the limitations and influence of the second stage on the process performance (gas heating value, cold gas efficiency, carbon conversion efficiency), along with other parameters. Comparison with a different thermal refining stage, i.e. thermal cracking (via partial oxidation) was also performed. The analysis is supported by experimental data from a pilot plant. PMID:26184896

  8. A comparative study of charcoal gasification in two types of spouted bed reactors

    Energy Technology Data Exchange (ETDEWEB)

    Abdul Salam, P. [Energy Field of Study, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Klongluang, Pathumthani 12120 (Thailand); Bhattacharya, S.C. [Energy Field of Study, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Klongluang, Pathumthani 12120 (Thailand)] e-mail: bhatta@ait.ac.th

    2006-03-01

    Gasification is considered to be a favourable method for converting a solid fuel into a more versatile gaseous fuel. Performance of a gasifier depends on the design of the gasifier, type of fuel used and air flow rate, etc. The applications of spouted bed for a variety of processes such as drying, coating, pyrolysis, gasification and combustion have been reported. Gasification of solid fuels in a spouted bed, which has certain potential advantages over other fluid bed configurations, appears to be an under-exploited technique so far. Central jet distributors are the most commonly used in the experimental studies that has been reported in the literature. Circular slit distributor is a new concept. This paper presents results of a comparative experimental study on air gasification of charcoal in central jet and circular slit inert sand spouted beds. The experiments were carried for an equivalence ratio of 0.25. The effect of spouting velocity and type of the distributor on the gasification performance were discussed. The steady state dense bed temperature varied between 979 and 1183 deg C for central jet spouted bed and between 964 and 1235 deg C for circular slit spouted bed. At higher spouting velocities, the gasification efficiency of the circular slit spouted bed was slightly more compared with that of central jet spouted bed.

  9. A comparative study of charcoal gasification in two types of spouted bed reactors

    Energy Technology Data Exchange (ETDEWEB)

    Salam, P.A.; Bhattacharya, S.C. [Asian Institute of Technology, Pathumthani (Thailand). School of Environmental, Resources and Development

    2006-03-01

    Gasification is considered to be a favourable method for converting a solid fuel into a more versatile gaseous fuel. Performance of a gasifier depends on the design of the gasifier, type of fuel used and airflow rate, etc. The applications of spouted bed for a variety of processes such as drying, coating, pyrolysis, gasification and combustion have been reported. Gasification of solid fuels in a spouted bed, which has certain potential advantages over other fluid bed configurations, appears to be an under-exploited technique so far. Central jet distributors are the most commonly used in the experimental studies that has been reported in the literature. Circular slit distributor is a new concept. This paper presents results of a comparative experimental study on air gasification of charcoal in central jet and circular slit inert sand spouted beds. The experiments were carried for an equivalence ratio of 0.25. The effect of spouting velocity and type of the distributor on the gasification performance were discussed. The steady state dense bed temperature varied between 979 and 1183{sup o}C for central jet spouted bed and between 964 and 1235{sup o}C for circular slit spouted bed. At higher spouting velocities, the gasification efficiency of the circular slit spouted bed was slightly more compared with that of central jet spouted bed. (author)

  10. Fixed (slow moving) bed updraft gasification of agricultural residues

    Energy Technology Data Exchange (ETDEWEB)

    Vigouroux, Rolando Zanzi [Royal Institute of Technology (KTH), Stockholm (Sweden). Dept. of Chemical Engineering and Technology], E-mail: rolando@ket.kth.se; Escalona, Ronoldy Faxas [University of Oriente, Santiago de Cuba (Cuba). Fac. of Mechanical Engineering], E-mail: faxas@fim.uo.edu.cu

    2009-07-01

    Birch, in form of pellets has been gasified in updraft fixed-bed gasifier using air as oxidation agent. The main objectives were to study the effect of the treatment conditions on the distribution of the products and the composition of product gas. The influence of the air flow rates on the composition of the producer gas has been studied. The amount of the biomass used in the experiments was varied between 1 and 4 kg and the flow rate of the air was varied from 1.1 to 2.6 m3/h. Increased airflow rates favored higher temperatures. Excessively high airflow rates resulted in fast consumption of the biomass and it also favored combustion over gasification and thus formation of lower amounts of combustible products. High airflow rates caused also higher yields of tars, due to the shorter residence time of the tar-rich gas in the gasifier and thus unfavorable conditions for tar cracking. (author)

  11. Air Gasification of Agricultural Waste in a Fluidized Bed Gasifier: Hydrogen Production Performance

    Directory of Open Access Journals (Sweden)

    A. B. Alias

    2009-05-01

    Full Text Available Recently, hydrogen production from biomass has become an attractive technology for power generation. The main objective pursued in this work is to investigate the hydrogen production potential from agricultural wastes (coconut coir and palm kernel shell by applying the air gasification technique. An experimental study was conducted using a bench-scale fluidized bed gasifier with 60 mm diameter and 425 mm height. During the experiments, the fuel properties and the effects of operating parameters such as gasification temperatures (700 to 900°C, fluidization ratio (2 to 3.33 m/s, static bed height (10 to 30 mm and equivalence ratio (0.16 to 0.46 were studied. It was concluded that substantial amounts of hydrogen gas (up to 67 mol% could be produced utilizing agricultural residues such as coconut and palm kernel shell by applying this fluidization technique. For both samples, the rise of temperature till 900°C favored further hydrocarbon reactions and allowed an increase of almost 67 mol% in the release of hydrogen. However, other parameters such as fluidizing velocity and feed load showed only minor effects on hydrogen yield. In conclusion, agricultural waste can be assumed as an alternative renewable energy source to the fossil fuels, and the environmental pollution originating from the disposal of agricultural residues can be partially reduced.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1985-10-01

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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

    2008-05-15

    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.

  14. Research into Biomass and Waste Gasification in Atmospheric Fluidized Bed

    Energy Technology Data Exchange (ETDEWEB)

    Skala, Zdenek; Ochrana, Ladislav; Lisy, Martin; Balas, Marek; Kohout, Premysl; Skoblja, Sergej

    2007-07-01

    Considerable attention is paid in the Czech Republic to renewable energy sources. The largest potential, out of them all, have biomass and waste. The aim therefore is to use them in CHP in smaller units (up to 5MWel). These are the subject of the research summarized in our article. The paper presents results of experimental research into gasification in a 100 kW AFB gasifier situated in Energy Institute, Faculty of Mechanical Engineering, Brno University of Technology, and fitted with gas cleaning equipment. Within the research, study was carried out into gas cleaning taking primary measures in the fluidized bed and using hot filter, metal-based catalytic filter, and wet scrubber. Descriptions and diagrams are given of the gasifier and new ways of cleaning. Results include: Impact of various fuels (farming and forest wastes and fast-growing woods and culm plants) on fuel gas quality. Individual kinds of biomass have very different thermal and physical properties; Efficiency of a variety of cleaning methods on content of dust and tars and comparison of these methods; and, Impact of gasifier process parameters on resultant gas quality. (auth)

  15. Inhibition and recovery of nitrification in treating real coal gasification wastewater with moving bed biofilm reactor

    Institute of Scientific and Technical Information of China (English)

    Huiqiang Li; Hongjun Han; Maoan Du; Wei Wang

    2011-01-01

    Moving bed biofilm reactor (MBBR) was used to treat real coal gasification wastewater.Nitrification of the MBBR was inhibited almost completely during start-up period.Sudden increase of influent total NH3 concentration was the main factor inducing nitrification inhibition.Increasing DO concentration in the bulk liquid (from 2 to 3 mg/L) had little effect on nitrification recovery.Nitrification of the MBBR recovered partially by the addition of nitrifying sludge into the reactor and almost ceased within 5 days.Nitrification ratio of the MBBR achieved 65% within 12 days by increasing dilute ratio of the influent wastewater with tap water.The ratio of nitrification decreased to 25% when infiuent COD concentration increased from 650 to 1000 mg/L after nitrification recovery and recovered 70%for another 4 days.

  16. Air gasification of rice husk in bubbling fluidized bed reactor with bed heating by conventional charcoal.

    Science.gov (United States)

    Makwana, J P; Joshi, Asim Kumar; Athawale, Gaurav; Singh, Dharminder; Mohanty, Pravakar

    2015-02-01

    An experimental study of air gasification of rice husk was conducted in a bench-scale fluidized bed gasifier (FBG) having 210 mm diameter and 1600 mm height. Heating of sand bed material was performed using conventional charcoal fuel. Different operating conditions like bed temperature, feeding rate and equivalence ratio (ER) varied in the range of 750-850 °C, 25-31.3 kg/h, and 0.3-0.38, respectively. Flow rate of air was kept constant (37 m(3)/h) during FBG experiments. The carbon conversion efficiencies (CCE), cold gas efficiency, and thermal efficiency were evaluated, where maximum CCE was found as 91%. By increasing ER, the carbon conversion efficiency was decreased. Drastic reduction in electric consumption for initial heating of gasifier bed with charcoal compared to ceramic heater was ∼45%. Hence rice husk is found as a potential candidate to use directly (without any processing) in FBG as an alternative renewable energy source from agricultural field. PMID:25446789

  17. Biomass Gasification in Internal Circulating Fluidized Beds: a Thermodynamic Predictive Tool

    Czech Academy of Sciences Publication Activity Database

    Miccio, F.; Svoboda, Karel; Schosger, J.-P.; Baxter, D.

    2008-01-01

    Roč. 25, č. 4 (2008), s. 721-726. ISSN 0256-1115 Institutional research plan: CEZ:AV0Z40720504 Keywords : fluidized bed * gasification * fluidized bed Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 0.830, year: 2008

  18. Artificial neural network models for biomass gasification in fluidized bed gasifiers

    DEFF Research Database (Denmark)

    Puig Arnavat, Maria; Hernández, J. Alfredo; Bruno, Joan Carles;

    2013-01-01

    Artificial neural networks (ANNs) have been applied for modeling biomass gasification process in fluidized bed reactors. Two architectures of ANNs models are presented; one for circulating fluidized bed gasifiers (CFB) and the other for bubbling fluidized bed gasifiers (BFB). Both models determin...... experimental data used R2 > 0.98. Furthermore a sensitivity analysis has been applied in each ANN model showing that all studied input variables are important....

  19. Ammonia Sampling and Analysis in Producer Gas from Fluidized-Bed Gasification

    Czech Academy of Sciences Publication Activity Database

    Esteve, J.; Jeremiáš, Michal; Pohořelý, Michael; Svoboda, Karel

    Madrid: CIEMAT, 2012, s. 1-3. [International Summer Schoolon Advanced Concepts and Process Schemes for CO2-Free Fluidized and Entrained Bed Co-Gasification of Coal , Biomass and Waste . Madrid (ES), 03.07.2012-06.07.2012] Grant ostatní: RFCR(XE) CT-2010-00009 Institutional support: RVO:67985858 Keywords : gasification * amonia * analysis Subject RIV: JE - Non-nuclear Energetics, Energy Consumption ; Use

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

    Energy Technology Data Exchange (ETDEWEB)

    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)

    2008-07-01

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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

    2009-04-15

    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%.

  2. Integrated Biomass Gasification with Catalytic Partial Oxidation for Selective Tar Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Lingzhi; Wei, Wei; Manke, Jeff; Vazquez, Arturo; Thompson, Jeff; Thompson, Mark

    2011-05-28

    requirement for commercial deployment of biomass-based power/heat co-generation and biofuels production. There are several commonly used syngas clean-up technologies: (1) Syngas cooling and water scrubbing has been commercially proven but efficiency is low and it is only effective at small scales. This route is accompanied with troublesome wastewater treatment. (2) The tar filtration method requires frequent filter replacement and solid residue treatment, leading to high operation and capital costs. (3) Thermal destruction typically operates at temperatures higher than 1000oC. It has slow kinetics and potential soot formation issues. The system is expensive and materials are not reliable at high temperatures. (4) In-bed cracking catalysts show rapid deactivation, with durability to be demonstrated. (5) External catalytic cracking or steam reforming has low thermal efficiency and is faced with problematic catalyst coking. Under this program, catalytic partial oxidation (CPO) is being evaluated for syngas tar clean-up in biomass gasification. The CPO reaction is exothermic, implying that no external heat is needed and the system is of high thermal efficiency. CPO is capable of processing large gas volume, indicating a very compact catalyst bed and a low reactor cost. Instead of traditional physical removal of tar, the CPO concept converts tar into useful light gases (eg. CO, H2, CH4). This eliminates waste treatment and disposal requirements. All those advantages make the CPO catalytic tar conversion system a viable solution for biomass gasification downstream gas clean-up. This program was conducted from October 1 2008 to February 28 2011 and divided into five major tasks. - Task A: Perform conceptual design and conduct preliminary system and economic analysis (Q1 2009 ~ Q2 2009) - Task B: Biomass gasification tests, product characterization, and CPO tar conversion catalyst preparation. This task will be conducted after completing process design and system economics analysis

  3. An Experimental and Numerical Investigation of Fluidized Bed Gasification of Solid Waste

    Directory of Open Access Journals (Sweden)

    Sharmina Begum

    2013-12-01

    Full Text Available Gasification is a thermo-chemical process to convert carbon-based products such as biomass and coal into a gas mixture known as synthetic gas or syngas. Various types of gasification methods exist, and fluidized bed gasification is one of them which is considered more efficient than others as fuel is fluidized in oxygen, steam or air. This paper presents an experimental and numerical investigation of fluidized bed gasification of solid waste (SW (wood. The experimental measurement of syngas composition was done using a pilot scale gasifier. A numerical model was developed using Advanced System for Process ENgineering (Aspen Plus software. Several Aspen Plus reactor blocks were used along with user defined FORTRAN and Excel code. The model was validated with experimental results. The study found very similar performance between simulation and experimental results, with a maximum variation of 3%. The validated model was used to study the effect of air-fuel and steam-fuel ratio on syngas composition. The model will be useful to predict the various operating parameters of a pilot scale SW gasification plant, such as temperature, pressure, air-fuel ratio and steam-fuel ratio. Therefore, the model can assist researchers, professionals and industries to identify optimized conditions for SW gasification.

  4. Process simulation of biomass gasification in a bubbling fluidized bed reactor

    International Nuclear Information System (INIS)

    Highlights: • Bubbling fluidized bed gasification of biomass is studied by computer simulation. • The effect of some critical parameters on gasification performance is studied. • The performance of air–steam gasification of wood chips is analyzed. • Model predictions are compared against available data from the literature. • The optimum operating conditions for the gasification are found. - Abstract: A detailed process model was developed to simulate the air–steam gasification of biomass in a bubbling fluidized bed for hydrogen and syngas production by coupling Aspen Plus simulator and dedicated FORTRAN subroutines. Effects of critical parameters, including gasification temperature, steam/biomass ratio (SBR), equivalence ratio (ER), and biomass particle size (BPS) on the composition of fuel gas were discussed. The results indicate that the high temperature is more favorable for production of useful syngas (H2 and CO) and hydrogen yield (HY). The simulation results also demonstrate that ER is the most important factor in the process; higher ER contributed to higher carbon conversion, tar reforming, and gas yield, however, it lowered gas caloric value and cold gas efficiency. However, steam injection recognized as a key factor to produce more hydrogen rich gas in the SBR range studied, but had a major effect on CO2 formation. The model is validated by experimental data and found relatively to be in good agreement

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

    Science.gov (United States)

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

    2016-06-01

    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

  6. Fluidized-bed gasification/pyrolysis technology for waste-to-energy

    Energy Technology Data Exchange (ETDEWEB)

    Ihara, T. [Ebara Corp., Tokyo (Japan)

    2008-07-01

    Fluidized-bed gasification of biomass and waste is expected to be a core technology for addressing global energy supply issues, fossil fuel conservation and environmental concerns regarding greenhouse gas emissions. Ebara Corporation has developed a unique fluidized-bed gasification technology known as the internally circulating fluidized-bed gasifier (ICFG), which can convert various forms of biomass and waste into high calorific product gas/oil that can be used as an alternative fuel for power generation as well as in chemical and liquid fuel synthesis. This paper summarized the general features of the ICFG as well as its research and development status. More than 10,900 hours of pyrolysis/gasification demonstration tests of various feedstocks and 120 hours of laboratory tests at 3 test facilities in Japan have revealed various levels of performance and the feasibility of the ICFG as a fluidized-bed gasification/pyrolysis technology for waste-to-energy and waste-to-chemical production. Several feasibility studies have been conducted to determine the commercial viability of this technology in Japan and elsewhere in the near future. 5 refs., 2 tabs., 9 figs.

  7. Gasification of low-grade fuels in a spouted bed for power generation

    Energy Technology Data Exchange (ETDEWEB)

    A.A. Belyaev [Institute for Fossil Fuels, Moscow (Russian Federation)

    2008-12-15

    Experimental data on the autothermal gasification of wastes from the flotation of Kuzbass coal of grade Zh and low-ash coal from the Kansk-Achinsk Basin in a spouted bed of an inert material at atmospheric pressure are presented. Capabilities for the development and use of this process for power generation based on closed-cycle gas turbine plants are analyzed.

  8. Woody waste air gasification in fluidized bed with Ca- and Mg-modified bed materials and additives

    International Nuclear Information System (INIS)

    This study focuses on the promotion of biomass gasification for hydrogen production in a fluidized bed reactor with the bed additives zeolite, CaO, and Ca- and Mg-based silica sands. The results show that zeolite has higher capacity for enhancing hydrogen promotion abilities than CaO with the amount was 200 g in tests. Regarding the Ca- and Mg-based silica sands, Ca/SiO2 decreases the CO2 selectivity and Mg/SiO2 enhances the H2 selectivity owing to CO2 adsorption via the formation of CaO and the promotion of the water gas shift reaction, respectively. The optimal concentration of Mg-based bed materials corresponds to a Mg concentration of 0.5 wt.%. The additives play important roles in increasing the reaction rate, enhancing the biomass gasification, and promoting carbon transformation. -- Graphical abstract: The aim of this study is not only in estimation of the influence of the alkaline metals concentrations, but also in preparation of the modified fluidization mediums. A basic stoichiometric analysis of alkaline concentration for hydrogen production during biomass gasification in fluidized bed is also in consideration. Highlights: ► Various bed-additives concentrations on syngas performance are discussed. ► All additives significantly increase rate of hydrogen production in gasification. ► Zeolite has higher capacity for enhancing hydrogen production rate than CaO. ► Ca-based additives promoted the heating value and cold gas efficiency. ► The optimal concentration of Mg-based additive was 0.5 wt.% for hydrogen production

  9. Effect of bed temperature and bed composition on agglomeration during gasification of high-sodium, high-sulphur lignite in a spouted fluidised bed

    Energy Technology Data Exchange (ETDEWEB)

    D.P. McCullough; P.J. Mullinger; P.J. Ashman [University of Adelaide, Adelaide, SA (Australia). Cooperative Research Centre for Clean Power from Lignite, School of Chemical Engineering

    2003-07-01

    Fluidised bed gasification (FBG) is an alternative process for coal utilisation that delivers improved efficiencies and lower temperature operation compared to conventional technology. Agglomeration and defluidisation are phenomena that have the potential to occur within fluidised bed reactors, which can interrupt stable process operation. While extensive work has been carried out investigating fluidised bed combustion of lignite, relatively little work has been carried out for lignite under fluidised bed gasification conditions. Gasification of high sodium, high sulphur content lignite in a spouted bed gasifier (SBG) indicates that agglomeration and defluidisation is only an issue when maximum bed temperature exceeds approximately 850{degree}C and air/fuel ratios of 2.5 outside of these conditions, defluidisation is not detected. It is also demonstrated that defluidisation occurs before agglomeration, rather than as a result of agglomeration as previously thought. The Rosin-Rammler method of describing particle size distribution is found to yield appropriate variables for quantification of the extent of agglomeration taking place in cases where defluidisation is a factor. However, it has been shown by this method that while initial results indicated that agglomeration extent varies directly with maximum bed temperature, further results have shown that other variables, such as superficial velocity, have a significant impact on the extent of agglomeration. Investigations are currently continuing. 9 refs., 8 figs., 9 tabs.

  10. Steam gasification of various feedstocks at a dual fluidised bed gasifier: Impacts of operation conditions and bed materials

    Energy Technology Data Exchange (ETDEWEB)

    Pfeifer, Christoph; Koppatz, Stefan; Hofbauer, Hermann [Vienna University of Technology, Institute of Chemical Engineering, Vienna (Austria)

    2011-03-15

    Gasification of biomass is an attractive technology for combined heat and power production as well as for synthesis processes such as production of liquid and gaseous biofuels. Dual fluidised bed (DFB) technology offers the advantage of a nearly nitrogen-free product gas mainly consisting of H{sub 2}, CO, CO{sub 2} and CH{sub 4}. The DFB steam gasification process has been developed at Vienna University of Technology over the last 15 years using cold flow models, laboratory units, mathematical modelling and simulation. The main findings of the experimental work at a 100-kW pilot scale unit are presented. Different fuels (wood pellets, wood chips, lignite, coal, etc.) and different bed materials (natural minerals such as olivine, limestones, calcites, etc. as well as modified olivines) have been tested and the influence on tar content as well as gas composition was measured and compared among the different components. Moreover, the influence of operating parameters such as fuel moisture content, steam/fuel ratio and gasification temperature on the product gas has been investigated. DFB steam gasification of solid biomass coupled with CO{sub 2} capture, the so-called absorption enhanced reforming (AER) process, is highlighted. The experiments in pilot scale led to commercial realisation of this technology in demonstration scale. Summarising, the DFB system offers excellent fuel flexibility to be used in advanced power cycles as well as in polygeneration applications. (orig.)

  11. Treatment of Mixed Wastes via Fixed Bed Gasification

    Energy Technology Data Exchange (ETDEWEB)

    None

    1998-10-28

    This report outlines the details of research performed under USDOE Cooperative Agreement DE-FC21-96MC33258 to evaluate the ChemChar hazardous waste system for the destruction of mixed wastes, defined as those that contain both RCRA-regulated haz- ardous constituents and radionuclides. The ChemChar gasification system uses a granular carbonaceous char matrix to immobilize wastes and feed them into the gasifier. In the gasifier wastes are subjected to high temperature reducing conditions, which destroy the organic constituents and immobilize radionuclides on the regenerated char. Only about 10 percent of the char is consumed on each pass through the gasifier, and the regenerated char can be used to treat additional wastes. When tested on a 4-inch diameter scale with a continuous feed unit as part of this research, the ChemChar gasification system was found to be effective in destroying RCRA surrogate organic wastes (chlorobenzene, dichloroben- zene, and napht.halene) while retaining on the char RCRA heavy metals (chromium, nickel, lead, and cadmium) as well as a fission product surrogate (cesium) and a plutonium surrogate (cerium). No generation of harmful byproducts was observed. This report describes the design and testing of the ChemChar gasification system and gives the operating procedures to be followed in using the system safely and effectively for mixed waste treatment.

  12. Co-gasification of a lignite/waste-tyre mixture in a moving bed

    Energy Technology Data Exchange (ETDEWEB)

    Straka, Pavel [Institute of Rock Structure and Mechanics, Academy of Sciences of the Czech, Republic, v.v.i., V Holesovickach 41, 182 09 Prague 8 (Czech Republic); Bucko, Zdenek [Sokolov Coal Corporation, Stare namesti 69, 356 00 Sokolov (Czech Republic)

    2009-10-15

    The thermal treatment of waste-tyre by co-gasification with lignite was investigated on a commercial scale during the Lurgi gasification process. The experiments proved that this material can be treated in a mixture with lignite in the process of oxygen-steam pressure co-gasification in a moving bed, because a waste-tyre admixture improves the net calorific value of the raw gas obtained by 3% in comparison with that from the gasification of lignite alone. Further, it was found that the H{sub 2}S and CH{sub 3}SH contents in the raw gas are lower in the case of co-gasification than those from the gasification of lignite alone. Considering the very low reactivity of the char from waste-tyre and the resultant unburned carbon in the ash, the optimal content of the waste-tyre admixture in the gasified feed should not exceed 10 wt.%, whereas short-term increases of up to 20 wt.% will not cause any technological problems or significant economic losses. (author)

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

    Directory of Open Access Journals (Sweden)

    Lucio Zaccariello

    2015-08-01

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-09-01

    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.)

  15. Energetic analysis of gasification of biomass by partial oxidation in supercritical water

    Institute of Scientific and Technical Information of China (English)

    Qingqing Guan; Chaohai Wei; Xinsheng Chai; Ping Ning; Senlin Tian; Junjie Gu; Qiuling Chen; Rongrong Miao

    2015-01-01

    Partial oxidation gasification in supercritical water could produce fuel gases (such as H2, CO and CH4) and signif-icantly reduce the energy consumption. In this work, an energetic model was developed to analyze the partial oxidative gasification of biomass (glucose and lignin) in supercritical water and the related key factors on which gasification under autothermal condition depended upon. The results indicated that the oxidant equiva-lent ratio (ER) should be over 0.3 as the concern about energy balance but less than 0.6 as the concern about fuel gas production. Feedstocks such as glucose and lignin also had different energy recovery efficiency. For ma-terials which can be efficiently gasified, the partial oxidation might be a way for energy based on the combustion of fuel gases. Aromatic materials such as lignin and coal are more potential since partial oxidation could produce similar amount of fuel gases as direct gasification and offer additional energy. Energy recovered pays a key role to achieve an autothermal process. Keeping heat exchanger efficiency above 80%and heat transfer coefficient below 15 kJ·s−1 is necessary to maintain the autothermal status. The results also indicated that the biomass loading should be above 15%but under 20%for an autothermal gasification, since the increase of biomass loading could improve the energy supplied but decrease the efficiency of gasification and gaseous yields. In general, some specific conditions exist among different materials.

  16. Two-stage dual fluidized bed gasification: Its conception and application to biomass

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Guangwen [Research Laboratory, IHI Corporation, Ltd., Isogo-Ku, Yokohama 235-8501 (Japan); Institute of Process Engineering, Chinese Academy of Sciences, Haidian, Beijing 100080 (China); Murakami, Takahiro [Research Laboratory, IHI Corporation, Ltd., Isogo-Ku, Yokohama 235-8501 (Japan); Clean Gas Group, National Institute of Advanced Science and Technology, Tsukuba, Ibaraki 305-8569 (Japan); Suda, Toshiyuki; Matsuzaw, Yoshiaki; Tani, Hidehisa [Research Laboratory, IHI Corporation, Ltd., Isogo-Ku, Yokohama 235-8501 (Japan)

    2009-01-15

    The quoted two-stage dual fluidized bed gasification (T-DFBG) devises the use of a two-stage fluidized bed (TFB) to replace the single-stage bubbling fluidized bed gasifier involved in the normally encountered dual fluidized bed gasification (N-DFBG) systems. By feeding fuel into the lower stage of the TFB, this lower stage functions as a fuel gasifier similar to that in the N-DFBG so that the upper stage of the TFB works to upgrade the produced gas in the lower stage and meanwhile to suppress the possible elutriation of fuel particles fed into the freeboard of the lower-stage bed. The heat carrier particles (HCPs) circulated from the char combustor enter first the upper stage of the TFB to facilitate the gas upgrading reactions occurring therein, and the particles are in turn forwarded into the lower stage to provide endothermic heat for fuel pyrolysis and gasification reactions. Consequently, with T-DFBG it is hopeful to increase gasification efficiency and decrease tar content in the produced gas. This anticipation was corroborated through gasifying dry coffee grounds in two 5.0kg/h experimental setups configured according to the principles of T-DFBG and N-DFBG, respectively. In comparison with the N-DFBG case, the test according to T-DFBG increased, the fuel C conversion and cold gas efficiency by about 7% and decreased tar content in the produced gas by up to 25% under similar reaction conditions. Test results demonstrated also that all these upgrading effects via adopting T-DFBG were more pronounced when a Ca-based additive was blended into the fuel. (author)

  17. Thermodynamic analysis of hydrogen rich synthetic gas generation from fluidized bed gasification of rice husk

    International Nuclear Information System (INIS)

    In the present work, the generation of hydrogen rich synthetic gas from fluidized bed steam gasification of rice husk has been studied. An equilibrium model based on equilibrium constant and material balance has been developed to predict the gas compositions. The equilibrium gas compositions are compared with the experimental data of the present group as well as of available literature. The energy and exergy analysis of the process have been carried out by varying steam to biomass ratio (ψ) within the range between 0.1-1.5 and gasification temperature from 600 oC to 900 oC. It is observed that both the energy and exergy efficiencies are maximum at the CBP (carbon boundary point) though the hydrogen production increases beyond the CBP. The HHV (higher heating value) and the external energy input both continuously increase with ψ. However, the hydrogen production initially increases with increase in temperature up to 800 oC and then becomes nearly asymptotic. The HHV decreases rapidly with increase in temperature and energy input increases. Therefore, gasification in lower temperature region is observed to be economical in terms of a trade off between external energy input and HHV of the product gas. -- Highlights: → Energy and exergy analysis of hydrogen rich synthetic gas generation from fluidized bed steam gasification of rice husk. → Effect of steam-to-biomass ration and gasification temperature is studied. → Maximum efficiencies occur at the (CBP) carbon boundary point though the hydrogen production increases beyond CBP. → Gasification in lower temperature region is observed to be optimum.

  18. Modeling of reaction kinetics in bubbling fluidized bed biomass gasification reactor

    Energy Technology Data Exchange (ETDEWEB)

    Thapa, R.K.; Halvorsen, B.M. [Telemark University College, Kjolnes ring 56, P.O. Box 203, 3901 Porsgrunn (Norway); Pfeifer, C. [University of Natural Resources and Life Sciences, Vienna (Austria)

    2013-07-01

    Bubbling fluidized beds are widely used as biomass gasification reactors as at the biomass gasification plant in Gussing, Austria. The reactor in the plant is a dual circulating bubbling fluidized bed gasification reactor. The plant produces 2MW electricity and 4.5MW heat from the gasification of biomass. Wood chips as biomass and olivine particles as hot bed materials are fluidized with high temperature steam in the reactor. As a result, biomass undergoes endothermic chemical reaction to produce a mixture of combustible gases in addition to some carbon-dioxide (CO2). The combustible gases are mainly hydrogen (H2), carbon monoxide (CO) and methane (CH4). The gas is used to produce electricity and heat via utilization in a gas engine. Alternatively, the gas is further processed for gaseous or liquid fuels, but still on the process of development level. Composition and quality of the gas determine the efficiency of the reactor. A computational model has been developed for the study of reaction kinetics in the gasification rector. The simulation is performed using commercial software Barracuda virtual reactor, VR15. Eulerian-Lagrangian approach in coupling of gas-solid flow has been implemented. Fluid phase is treated with an Eulerian formulation. Discrete phase is treated with a Lagrangian formulation. Particle-particle and particle-wall interactions and inter-phase heat and mass transfer have been taken into account. Series of simulations have been performed to study model prediction of the gas composition. The composition is compared with data from the gasifier at the CHP plant in Güssing, Austria. The model prediction of the composition of gases has good agreements with the result of the operating plant.

  19. H2 rich gas production via pressurized fluidized bed gasification of sawdust with in situ CO2 capture

    International Nuclear Information System (INIS)

    Highlights: • A pressurized fluidized bed reactor was designed and constructed for gasification tests. • CaO sorption enhanced gasification of sawdust was investigated under pressurized conditions. • H2 production was promoted with the increase in gasification pressure, CaO/C, H2O/C and T. • Pressurized operation promoted gasification reactions and enhanced CaO carbonation. • Pressurized operation increased the carbon conversion and cold gas efficiency of gasification. - Abstract: The continuous increase in energy demand and the growing attention on global warming worldwide have aroused great research interest in a novel near zero emission energy utilization system which is based on CaO sorption enhanced gasification. This paper presents the experimental results of pressurized CaO sorption enhanced sawdust gasification in a self-design pressurized fluidized bed gasifier, aiming to survey the effects of reaction pressure, CaO to carbon mole ratio (CaO/C), steam to carbon mole ratio (H2O/C) and reaction temperature (T) on hydrogen (H2) production under pressurized gasification conditions. Results showed that the pressurized operation not only promoted gasification reactions, but also apparently enhanced CaO carbonation. Within the experimental ranges investigated in this work, H2 fraction and H2 yield were both elevated with the increase in reaction pressure, CaO/C, H2O/C and T. Comparing with previous atmospheric fluidized bed gasification results, pressurized gasification was capable of producing syngas with higher H2 fraction and lower CO2 fraction even at lower CaO/C, H2O/C and T. It was also verified that pressurized operation increased the carbon conversion and cold gas efficiency for CaO sorption enhanced sawdust gasification

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

    Science.gov (United States)

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

    2014-10-01

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

  1. Fluidized bed gasification of sugar cane bagasse. Influence on gas composition

    Energy Technology Data Exchange (ETDEWEB)

    Esperanza, E.; Aleman, Y. [Univ. of las Villas, Santa Clara (Cuba). Biomass Thermoconversion group/CETA; Arauzo, J.; Gea, G. [Univ. of Zaragoza (Spain). Chemical and Environmental Engineering Dept.

    1999-07-01

    Air and steam gasification of biomass has been studied at different temperatures. The experiments have been carried out in a bench scale plant. It consists of an atmospheric bubbling fluidized bed gasifier heated by an electric furnace. The gasification process have been carried out at high heating rates and low residence time of the gases. The biomass used has been Cuban sugar cane bagasse. Three operating parameters have been evaluated to improve the gas composition: Equivalence Ratio (E.R.) in the range of 0.15 to 0.55; the bed temperature from 780 to 920 deg C; and steam/biomass ratio (S/B) from 0.1 g/g to 0.5 g/g. The results obtained show the effect of these operating parameters in gas composition and the conditions to obtain higher yield to gas and else the maximum energy.

  2. Modeling and simulation of biomass air-steam gasification in a fluidized bed

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    By considering the features of fluidized-bed reactors and the kinetic mechanism of biomass gasification,a steady-state,isothermal,one-dimensional and twophase mathematical model of biomass gasification kinetics in bubbling fluidized beds was developed.The model assumes the existence of two phases - a bubble and an emulsion phase - with chemical reactions occurring in both phases.The axial gas dispersion in the two phases is accounted for and the pyrolysis of biomass is taken to be instantaneous.The char and gas species CO,CO2,H2,H2O,CH4 and 8 chemical reactions are included in the model.The mathematical model belongs to a typical boundary value problem of ordinary differential equations and its solution is obtained by a Matlab program.Utilizing wood powder as the feedstock,the calculated data show satisfactory agreement with experimental results and proves the effectiveness and reliability of the model.

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

    OpenAIRE

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

    2012-01-01

    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...

  4. Fluidized Bed Gasification of Biomass: the Yield of Hydrogen under Different Operating Conditions

    Czech Academy of Sciences Publication Activity Database

    Jeremiáš, Michal; Pohořelý, Michael; Svoboda, Karel; Skoblia, S.; Beňo, Z.; Kameníková, Petra; Durda, Tomáš

    Praha : KANAG - TISK, 2014 - (Bouzek, K.; Doucek, A.), s. 38 ISBN 978-80-7080-878-8. [5International Conference on Hydrogen Technologies /5./. Prague (CZ), 02.04.2014-04.04.2014] R&D Projects: GA MŠk(CZ) 7C11009 Grant ostatní: RFCS(XE) RFCR-CT-2010-0009 Institutional support: RVO:67985858 Keywords : biomass * gasification * dolomite * limestone * fluidized bed Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  5. Mathematical modeling of municipal solid waste plasma gasification in a fixed-bed melting reactor

    OpenAIRE

    Zhang, Qinglin

    2011-01-01

    The increasing yield of municipal solid waste (MSW) is one of the main by-products of modern society. Among various MSW treatment methods, plasma gasification in a fixed-bed melting reactor (PGM) is a new technology, which may provide an efficient and environmental friendly solution for problems related to MSW disposals. General objectives of this work are to develop mathematical models for the PGM process, and using these models to analyze the characteristics of this new technology. In this ...

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

    Czech Academy of Sciences Publication Activity Database

    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

  7. Air Gasification of Agricultural Waste in a Fluidized Bed Gasifier: Hydrogen Production Performance

    OpenAIRE

    A. B. Alias; Reza Alipour Moghadam; M. A. Mohd Salleh; W. A. Wan Ab Karim Ghani

    2009-01-01

    Recently, hydrogen production from biomass has become an attractive technology for power generation. The main objective pursued in this work is to investigate the hydrogen production potential from agricultural wastes (coconut coir and palm kernel shell) by applying the air gasification technique. An experimental study was conducted using a bench-scale fluidized bed gasifier with 60 mm diameter and 425 mm height. During the experiments, the fuel properties and the effects of operating paramet...

  8. Formation and removal of biomass-derived contaminants in fluidized-bed gasification processes

    Energy Technology Data Exchange (ETDEWEB)

    Kurkela, E. [VTT Energy, Espoo (Finland). Energy Production Technologies

    1996-12-31

    The objectives of this thesis were to examine the effects of the feedstock and the operating conditions of a fluidized-bed gasifier on the formation of tars and nitrogen-containing compounds and to study the effectiveness of the hot gas cleaning methods developed for the removal of particulates, alkali metals, tars and nitrogen-containing compounds. The most essential part of the work was carried out in the pressurized fluidized-bed gasification test facilities composed of an air-blown bubbling fluidized-bed gasifier and subsequent hot gas filter unit. The operation pressure of the test rig could be varied in the range 0.3 - 1.0 MPa and the maximum allowable gasification temperature was 1 050 deg C. The maximum capacity with biomass fuels was 80 kg/h. A wide range of feedstocks from hard coals, lignite and peat to different wood derived fuels and straw were used in the gasification tests. Two different types of ceramic filters were tested in the filter unit connected to the pressurized fluidized-bed gasifier. The filter unit was operated in a temperature range of 400 - 740 deg C. The particulate removal requirements set by the gas turbines were met by both types of filters and with product gases derived from all the feedstocks tested. In addition to the gasification and gas filtration tests, catalytic tar and ammonia decomposition was studied using both laboratory and bench-scale test facilities. Inexpensive calcium-based bulk materials, dolomites and limestones, were efficient tar decomposition catalysts in atmospheric-pressure tests

  9. Experimental determination of bed agglomeration tendencies of some common agricultural residues in fluidized bed combustion and gasification

    Energy Technology Data Exchange (ETDEWEB)

    Natarajan, E.; Rao, A.N. [Anna University, Madras (India). Centre for New and Renewable Sources of Energy; Ohman, M.; Nordin, A. [Umea University (Sweden). Energy Technology Centre; Gabra, M. [Lulea University of Technology (Sweden). Div. of Energy Engineering; Liliedahl, T. [Royal Institute of Technology, Stockholm (Sweden). Dept. of Chemical Engineering and Technology

    1998-12-31

    Ever increasing energy demand and the polluting nature of existing fossil fuel energy sources demonstrate the need for other non-polluting and renewable sources of energy. The agricultural residues available in abundance in many countries can be used for power generation. The fluidized bed technology seems to be suitable for converting a wide range of agricultural residues into energy, due to its inherent advantages of fuel flexibility, low operating temperature and isothermal operating condition. The major ash-related problem encountered in fluidized beds is agglomeration which, in the worst case, may result in total defluidization and unscheduled downtime. The initial agglomeration temperature for some common tropical agricultural residues were experimentally determined by using a newly developed method based on the controlled fluidized bed agglomeration test. The agricultural residues chosen for the study were rice husk, bagasse, cane trash and olive flesh. The results showed that the initial agglomeration temperatures were less than the initial deformation temperature predicted by the ASTM standard ash fusion tests for all fuels considered. The initial agglomeration temperatures of rice husk and bagasse were more than 1000{sup o}C. The agglomeration of cane trash and olive flesh was encountered at relatively low temperatures and their initial agglomeration temperatures in gasification were lower than those in combustion with both bed materials. The use of lime as bed material instead of quartz improved the agglomeration temperature of cane trash and olive flesh in combustion and decreased the same in gasification. The results indicate that rice husk and bagasse can be used in the fluidized bed for energy generation since their agglomeration temperatures are sufficiently high. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1983-09-01

    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.

  11. International evaluation of the programme on fluid bed combustion and gasification

    Energy Technology Data Exchange (ETDEWEB)

    Kremer, H. [Ruhr Univ., Bochum (Germany); Magnusson, B.F. [Norwegian Univ. of Science and Technology, Trondheim (Norway); Reed, T. [Colorado School of Mines (United States)

    1996-12-31

    This report on the Swedish National Program on Fluid Bed Combustion and Gasification is part of the on-going evaluation process adopted by the funding organization NUTEK. This agency has invited the undersigned to act as members of an international panel responsible for evaluating the progress made in 9 projects initiated between 1993-1996. The output of this evaluation procedure is given in this report. The main aim of the Fluid Bed Combustion and Gasification Program is to develop industrially relevant knowledge and competence in experimental and computational techniques capable of characterizing the flow, heat transfer, combustion, gasification, ash formation and deposition and emissions in fluid bed gasifiers and combustors. To achieve this aim NUTEK is sponsoring research in a number of universities and encourages close cooperation between universities and industry. In the evaluation of the various sponsored research programs, the evaluation committee has considered the following key points: relevance of research to industrial needs; originality of research; program management; adequacy of resources; degree of collaboration between industry and academia; international standing of research. In this report comments and recommendations are made on individual projects as well as on the programme in general and they express the unanimous view of the panel members

  12. Hydrodynamic study on gasification of biomass in a fluidized bed gasifier

    OpenAIRE

    S.BASKARA SETHUPATHY; Natarajan, E.

    2012-01-01

    Current scenario of energy insecurity urges us to realize the importance of alternate energy sources. In country with variety of vegetation like India, Biomass finds its place of which fluidized bed gasification of biomass could be more effective. This paper emphasizes the importance of a fluidized bed gasifier for energy conversion of agro-residues for useful purposes. Coconut Shell and Ground nut shell of gross calorific value 19.43MJ/kg and 14.91 MJ/kg respectively are taken for the study....

  13. Damage monitoring of refractory wall in a generic entrained-bed slagging gasification system

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, S.; Sarkar, S.; Gupta, S.; Ray, A. [Penn State University, University Park, PA (USA). Dept. of Mechanical Engineering

    2008-12-15

    The main cause of performance degradation in entrained-bed slagging gasification systems is attributed to evolution of structural damage in the refractory walls. Early detection of such damage is necessary to avert unscheduled shutdown of a gasification plant. This paper develops an integrated computer simulation model of a generic entrained-bed slagging gasifier for formulation of a damage prediction algorithm with the objective of real-time degradation monitoring and condition-based maintenance of refractory walls. The integrated simulation model yields: (a) quasi-steady-state spatial temperature profiles at any cross-section of the gasification system, and (b) dynamic response of the refractory wall temperature that is measured by an array of sensors installed at specified locations on the external surface of the gasifier wall. The key idea for early detection of refractory-wall damage is built upon the fact that a local anomaly (i.e. deviation from the nominal condition) is likely to influence the temperature gradient in the refractory wall due to changes in the thermal impedance. The information from dynamic response of refractory temperature is extracted in a compressed form as statistical patterns of evolving anomaly through usage of a recently reported data-driven pattern identification tool called symbolic dynamic filtering (SDF). The results of this model-based investigation show that the proposed anomaly detection and damage prediction method is potentially capable of characterizing the health status of refractory walls in particular and the entire gasification system in general. The SDF algorithms in this paper are implemented on the MATLAB platform and are interfaced with the gasification plant simulation model for emulation of real-time degradation monitoring.

  14. Gasification of oak sawdust, mesquite, corn stover and cotton gin trash in a countercurrent fluidized bed pilot reactor

    Energy Technology Data Exchange (ETDEWEB)

    Beck, S.R.; Wang, M.J.; Hightower, J.A.

    1981-01-01

    The Synthesis Gas From Manure (SGFM) process was designed to convert cattle feedlot manure to ammonia synthesis gas. Current work is aimed at using any biomass feedstock to produce either medium-Btu gas or chemical feedstocks. This paper presents a comparison of the experimental results compiled on gasification of oak sawdust, corn stover, mesquite, and cotton gin treash in the SGFM pilot plant. The SGFM process is based on a countercurrent, fluidized bed reactor. In this system, biomass is fed to the top of the reactor resulting in the fresh feed being partially dried by direct contact with hot product gas prior to entering the reaction zone. A weighted comparison of the product gas, hydrocarbon, and hydrogen yields, gas quality, calorific value of product gas, percentage conversion of raw feed heating value to gas heating value, and operability of each feed indicated that oak sawdust was the best feedstock. (Refs. 7).

  15. Gasification of refuse derived fuel in a fixed bed reactor for syngas production

    International Nuclear Information System (INIS)

    Steam gasification of two different refuse derived fuels (RDFs), differing slightly in composition as well as thermal stability, was carried out in a fixed-bed reactor at atmospheric pressure. The proximate and ultimate analyses reveal that carbon and hydrogen are the major components in RDFs. The thermal analysis indicates the presence of cellulose and plastic based materials in RDFs. H2 and CO are found to be the major products, along with CO2 and hydrocarbons resulting from gasification of RDFs. The effect of gasification temperature on H2 and CO selectivities was studied, and the optimum temperature for better H2 and CO selectivity was determined to be 725 deg. C. The calorific value of product gas produced at lower gasification temperature is significantly higher than that of gas produced at higher process temperature. Also, the composition of RDF plays an important role in distribution of products gas. The RDF with more C and H content is found to produce more amounts of CO and H2 under similar experimental conditions. The steam/waste ratio showed a notable effect on the selectivity of syngas as well as calorific value of the resulting product gas. The flow rate of carrier gas did not show any significant effect on products yield or their distribution

  16. Gasification of bio char from empty fruit bunch in a fluidized bed

    International Nuclear Information System (INIS)

    Full text: Bio char from empty fruit bunch was gasified in a fluidized bed reactor using compressed air as a gasifying agent. The experiment was conducted in the temperature ranges of 500-850 degree Celsius and the equivalence ratio, temperature and size of the feedstock was varied. A series of parameters such as gas yield, overall carbon conversion, gas quality, and composition, were measured as a function of temperature, equivalence ratio and temperature. Results obtained were compared to the actual values of coal and other gasification feedstock reveal that, bio char has the potential to replace coal as a gasification agent in power plants .Hydrogen gas from bio char was also optimized during the experiment. There is great potential of making Hydrogen from Bio char through thermo chemical gasification It was observed that it has a very great potential of being upgraded to Fischer Tropsh fuels. There is a great opportunity of using this char from empty fruit bunch as an alternative fuel in power plants and all the adverse effects of coal gasification can be counteracted. (author)

  17. Artificial neural network modelling approach for a biomass gasification process in fixed bed gasifiers

    International Nuclear Information System (INIS)

    Highlights: • 2 Different equilibrium models are developed and their performance is analysed. • Neural network prediction models for 2 different fixed bed gasifier types are developed. • The influence of different input parameters on neural network model performance is analysed. • Methodology for neural network model development for different gasifier types is described. • Neural network models are verified for various operating conditions based on measured data. - Abstract: The number of the small and middle-scale biomass gasification combined heat and power plants as well as syngas production plants has been significantly increased in the last decade mostly due to extensive incentives. However, existing issues regarding syngas quality, process efficiency, emissions and environmental standards are preventing biomass gasification technology to become more economically viable. To encounter these issues, special attention is given to the development of mathematical models which can be used for a process analysis or plant control purposes. The presented paper analyses possibilities of neural networks to predict process parameters with high speed and accuracy. After a related literature review and measurement data analysis, different modelling approaches for the process parameter prediction that can be used for an on-line process control were developed and their performance were analysed. Neural network models showed good capability to predict biomass gasification process parameters with reasonable accuracy and speed. Measurement data for the model development, verification and performance analysis were derived from biomass gasification plant operated by Technical University Dresden

  18. Theoretical and experimental investigation of biomass gasification process in a fixed bed gasifier

    International Nuclear Information System (INIS)

    This investigation concerns the process of air biomass gasification in a fixed bed gasifier. Theoretical equilibrium calculations and experimental investigation of the composition of syngas were carried out and compared with findings of other researchers. The influence of excess air ratio (λ) and parameters of biomass on the composition of syngas were investigated. A theoretical model is proposed, based on the equilibrium and thermodynamic balance of the gasification zone. The experimental investigation was carried out at a setup that consists of a gasifier connected by a pipe with a water boiler fired with coal (50 kWth). Syngas obtained in the gasifier is supplied into the coal firing zone of the boiler, and co-combusted with coal. The moisture content in biomass and excess air ratio of the gasification process are crucial parameters, determining the composition of syngas. Another important parameter is the kind of applied biomass. Despite similar compositions and dimensions of the two investigated feedstocks (wood pellets and oats husk pellets), compositions of syngas obtained in the case of these fuels were different. On the basis of tests it may be stated that oats husk pellets are not a suitable fuel for the purpose of gasification.

  19. Experimental study on temperature profile of fixed - bed gasification of oil-palm fronds

    Science.gov (United States)

    Atnaw, Samson M.; Sulaiman, Shaharin A.; Moni, M. Nazmi Z.

    2012-06-01

    Currently the world's second largest palm oil producer Malaysia produces large amount of oil palm biomass each year. The abundance of the biomass introduces a challenge to utilize them as main feedstock for heat and energy generation. Although some oil palm parts and derivatives like empty fruit bunch and fibre have been commercialized as fuel, less attention has been given to oil palm fronds (OPF). Initial feasibility and characterization studies of OPF showed that it is highly feasible as fuel for gasification to produce high value gaseous fuel or syngas. This paper discusses the experimental gasification attempt carried out on OPF using a 50 kW lab scale downdraft gasifier and its results. The conducted study focused on the temperature distributions within the reactor and the characteristics of the dynamic temperature profile for each temperature zones during operation. OPF feedstock of one cubic inch in individual size with 15% average moisture content was utilized. An average pyrolysis zone temperature of 324°Cand an average oxidation zone temperature of 796°Cwere obtained over a total gasification period of 74 minutes. A maximum oxidation zone temperature of 952°Cwas obtained at 486 lpm inlet air flow rate and 10 kg/hr feedstock consumption rate. Stable bluish flare was produced for more than 70% of the total gasification time. The recorded temperature profiles produced closely similar patterns with the temperature profiles recorded from the gasification of woody materials. Similar temperature profile was obtained comparing the results from OPF gasification with that of woody biomass. Furthermore, the successful ignition of the syngas produced from OPF gasification ascertained that OPF indeed has a higher potential as gasification feedstock. Hence, more detailed studies need to be done for better understanding in exploiting the biomass as a high prospect alternative energy solution. In addition, a study of the effect of initial moisture content of OPF

  20. Experimental study on catalytic steam gasification of natural coke in a fluidized bed

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Changsui; Lin, Liangsheng; Pang, Keliang; Xiang, Wenguo; Chen, Xiaoping [School of Energy and Environment, Southeast University, Nanjing 210096, Jiangsu (China)

    2010-08-15

    The gasification characteristics of natural coke from Peicheng mine with steam were investigated in a fluidized bed reactor. The effects of catalyst type, composition and dosage of catalyst on the yield, components and heating value of product gas, and carbon conversion rate were examined. The results show that fluidized bed gasification technology is an effective way to gasify natural coke. Also the results indicate that individual addition of K-, Ca-, Fe-, Ni-based catalyst effectively increases the gasification reaction rate of the natural coke samples. With the increase in catalyst dosage, the yield and heating value of product gas per hour increase obviously, and carbon conversion rate is improved substantially. Each of aforementioned catalysts has similar catalytic effect and trend, among which the effect of Ca-based catalyst is a little weaker. The optimum metal atom ratio of mixed catalyst is Fe/Ni/others 35/55/10, and the mixed catalyst displays maximum catalytic performance when the catalyst dosage in the natural coke is about 4%. The experimental findings provide an interesting reference for large-scale development and utilization of natural coke. (author)

  1. CFD based combustion model for sewage sludge gasification in a fluidized bed

    Institute of Scientific and Technical Information of China (English)

    Yiqun WANG; Lifeng YAN

    2009-01-01

    Gasification is one potential way to use sewage sludge as renewable energy and solve the environmental problems caused by the huge amount of sewage sludge. In this paper, a three-dimensional Computational Fluid Dynamics (CFD) model has been developed to simulate the sewage sludge gasification process in a fluidized bed. The model describes the complex physical and chemical phenomena in the gasifier including turbulent flow, heat and mass transfer, and chemical reactions. The model is based on the Eulerian-Lagrangian concept using the non-premixed combustion modeling approach. In terms of the CFD software FLUENT, which represents a powerful tool for gasifIer analysis, the simulations provide detailed information on the gas products and temperature distribution in the gasifier. The model sensitivity is analyzed by performing the model in a laboratory-scale fluidized bed in the literature, and the model validation is carried out by comparing with experimental data from the literature. Results show that reasonably good agreement was achieved. Effects of temperature and Equivalence Ratio (ER) on the quality of product syngas (H2 + CO) are also studied.

  2. Hydrodynamic study on gasification of biomass in a fluidized bed gasifier

    Directory of Open Access Journals (Sweden)

    S.BASKARA SETHUPATHY

    2012-01-01

    Full Text Available Current scenario of energy insecurity urges us to realize the importance of alternate energy sources. In country with variety of vegetation like India, Biomass finds its place of which fluidized bed gasification of biomass could be more effective. This paper emphasizes the importance of a fluidized bed gasifier for energy conversion of agro-residues for useful purposes. Coconut Shell and Ground nut shell of gross calorific value 19.43MJ/kg and 14.91 MJ/kg respectively are taken for the study. The particle size is restricted not to exceed 3mm. Various empirical correlations involved in fluidization are studied and their interdependence is detailed. From various published data, importance of inert materials and their relative proportions with biomass fuels are studied and optimum biomass to sand ratio is fixed as 10 to 15% by mass. Equations for predicting the minimum fluidization velocities of these mixtures are also discussed. Variations of Fluidization parameters such asminimum fluidization velocity, bubble rise velocity, expanded bed height with respect to temperature, equivalence ratio, particle size is studied and their quantification is analyzed. A 108 mm internal diameter and 1400 mm high FBG is used for the study. Fuel is fed through screw feeder and air is supplied through blower. In the down stream side cyclone separator is placed after which the sampling and burner lines are connected. A regression model is developed and the feasibility of gasifying coconut shell and groundnut shell are discussed. Earlier and present work of coconut shell gasification proves fluidized bed gasification is more appropriate for agro residues.

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

    Energy Technology Data Exchange (ETDEWEB)

    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

    2009-03-15

    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.

  4. Improving the performance of fluidized bed biomass/waste gasifiers for distributed electricity: A new three-stage gasification system

    International Nuclear Information System (INIS)

    Methods to increase the conversion of char and tar in fluidized bed gasifiers (FBG) are discussed, with the focus on small to medium-size biomass/waste gasifiers for power production (from 0.5 to 10 MWe). Optimization of such systems aims at (i) maximizing energy utilization of the fuel (maximizing char conversion), (ii) minimizing secondary treatment of the gas (by avoiding complex tar cleaning), and (iii) application in small biomass-to-electricity gasification plants. The efficiency of various measures to increase tar and char conversion within a gasification reactor (primary methods) is discussed. The optimization of FBG by using in-bed catalysts, by addition of steam and enriched air as gasification agent, and by secondary-air injection, although improving the process, is shown to be insufficient to attain the gas purity required for burning the gas in an engine to produce electricity. Staged gasification is identified as the only method capable of reaching the targets mentioned above with reasonable simplicity and cost, so it is ideal for power production. A promising new stage gasification process is presented. It is based on three stages: FB devolatilization, non-catalytic air/steam reforming of the gas coming from the devolatilizer, and chemical filtering of the gas and gasification of the char in a moving bed supplied with the char generated in the devolatilizer. Design considerations and comparison with one-stage FBG are discussed. - Highlights: ► Optimization of fluidized bed biomass gasifiers is reviewed. ► The effectiveness of primary measures for tar and char conversion for small/medium scale units are discussed. ► Feasible measures for adjusting operation of fluidized bed gasifiers are assessed. ► A new three-staged-fluidized-bed gasification system for biomasses and wastes is proposed.

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

    International Nuclear Information System (INIS)

    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

  6. Equilibrium modeling of gasification: Gibbs free energy minimization approach and its application to spouted bed and spout-fluid bed gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Jarungthammachote, S.; Dutta, A. [Energy Field of Study, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Klongluang, Pathumthani 12120 (Thailand)

    2008-06-15

    Spouted beds have been found in many applications, one of which is gasification. In this paper, the gasification processes of conventional and modified spouted bed gasifiers were considered. The conventional spouted bed is a central jet spouted bed, while the modified spouted beds are circular split spouted bed and spout-fluid bed. The Gibbs free energy minimization method was used to predict the composition of the producer gas. The major six components, CO, CO{sub 2}, CH{sub 4}, H{sub 2}O, H{sub 2} and N{sub 2}, were determined in the mixture of the producer gas. The results showed that the carbon conversion in the gasification process plays an important role in the model. A modified model was developed by considering the carbon conversion in the constraint equations and in the energy balance calculation. The results from the modified model showed improvements. The higher heating values (HHV) were also calculated and compared with the ones from experiments. The agreements of the calculated and experimental values of HHV, especially in the case of the circular split spouted bed and the spout-fluid bed were observed. (author)

  7. Industrial demonstration plant for the gasification of herb residue by fluidized bed two-stage process.

    Science.gov (United States)

    Zeng, Xi; Shao, Ruyi; Wang, Fang; Dong, Pengwei; Yu, Jian; Xu, Guangwen

    2016-04-01

    A fluidized bed two-stage gasification process, consisting of a fluidized-bed (FB) pyrolyzer and a transport fluidized bed (TFB) gasifier, has been proposed to gasify biomass for fuel gas production with low tar content. On the basis of our previous fundamental study, an autothermal two-stage gasifier has been designed and built for gasify a kind of Chinese herb residue with a treating capacity of 600 kg/h. The testing data in the operational stable stage of the industrial demonstration plant showed that when keeping the reaction temperatures of pyrolyzer and gasifier respectively at about 700 °C and 850 °C, the heating value of fuel gas can reach 1200 kcal/Nm(3), and the tar content in the produced fuel gas was about 0.4 g/Nm(3). The results from this pilot industrial demonstration plant fully verified the feasibility and technical features of the proposed FB two-stage gasification process. PMID:26849201

  8. Energetic use of wood and biomass by circulating fluidized bed gasification. Final report

    International Nuclear Information System (INIS)

    The project's objective was the development and utilization of a biomass gasification process based on CFB-gasification with dry hot gas upgrading for IC-engine operation. Construction and operation of a test plant at pilot scale with 400 kW fuel input capacity. Development of a mathematical model for CFB-gasification. Reliable operation of CFB-gasifier, good results at partial load and good behaviour at changing the load. Air blown gasification of wood chips yielded lower heating values (LHV) up to 5500 kJ/m3 (s.T.p., dry) for the gas. Main attention to measures for tar removal. Target value was 3 (s.T.p.) for napthalene + PAH. Average amount of tar after CBF-gasifier at 3000-5000 mg/m3 (s.T.p.). Primary measures aiming at a decreased tar production were not suitable for achieving the target value. Several secondary measures were tested. Tars could almost completely be cracked or reformed by special catalysts. In continuous test runs of more than 100 h duration tar contents less than 50 mg/m3 were achieved. A scale up for a catalytic gas cleaning system based on the results is planned. Estimations of economics show the process concept to be advantegous for plants up to 30 MW fuel input capacity. Profitable costs for combined heat and power production from biomass can be expected. (orig.)

  9. The O2-enriched air gasification of coal, plastics and wood in a fluidized bed reactor

    International Nuclear Information System (INIS)

    Highlights: ► The effect of the O2 in the gasification stream of a BFB gasifier has been studied. ► Main advantage of the O2-enriched air is the increasing of the bed temperature.► No remarkable effects on tar reduction. Decreasing of recognized PAHs. ► Gasification reactions completed inside the dense bed and splashing zone. ► Polycondensation reactions occur mainly in the freeboard region. - Abstract: The effect of oxygen-enriched air during fluidized bed co-gasification of a mixture of coal, plastics and wood has been investigated. The main components of the obtained syngas were measured by means of on-line analyzers and a gas chromatograph while those of the condensate phase were off-line analysed by means of a gas chromatography–mass spectrometer (GC–MS). The characterization of condensate phase as well as that of the water used as scrubbing medium completed the performed diagnostics. The experimental results were further elaborated in order to provide material and substances flow analyses inside the plant boundaries. These analyses allowed to obtain the main substance distribution between solid, gaseous and condensate phases and to estimate the conversion efficiency of carbon and hydrogen but also to easily visualise the waste streams produced by the process. The process performance was then evaluated on the basis of parameters related to the conversion efficiency of fuels into valuable products (i.e. by considering tar and particulate as process losses) as well as those related to the energy recovery.

  10. Gasification of Biochar from Empty Fruit Bunch in a Fluidized Bed Reactor

    OpenAIRE

    M. A. Mohd Salleh; Nsamba Hussein Kisiki; H. M. Yusuf; W. A. Wan Ab Karim Ghani

    2010-01-01

    A biochar produced from empty fruit bunches (EFB) was gasified in a fluidized bed using air to determine gas yield, overall carbon conversion, gas quality, and composition as a function of temperature. The experiment was conducted in the temperature range of 500–850 °C. It was observed that biochar has the potential to replace coal as a gasification agent in power plants. Hydrogen gas from biochar was also optimized during the experiment. High temperatures favor H 2 and CO formation. There...

  11. Low-temperature gasification of waste tire in a fluidized bed

    International Nuclear Information System (INIS)

    In order to recovery energy and materials from waste tire efficiently, low-temperature gasification is proposed. Experiments are carried out in a lab-scale fluidized bed at 400-800 deg. C when equivalence ratio (ER) is 0.2-0.6. Low heat value (LHV) of syngas increases with increasing temperature or decreasing ER, and the yield is in proportion to ER linearly. The yield of carbon black decreases with increasing temperature or ER lightly. When temperature is over 600 deg. C, characteristics of carbon black is similar. When temperature is over 700 deg. C, LHV of syngas rises up lightly with increasing temperature, which indicates that it hardly facilitates gasification any more. It is suitable for tire gasification when temperature is 650-700 deg. C and ER is 0.2-0.4. Under this condition, LHV and yield of syngas are about 4000-9000 kJ/Nm3 and 1.8-3.7 Nm3/kg, respectively; surface area and yield of carbon black lie in range of 20-30 m3/g and 550-650 g/kg, respectively. The carbon balance of these experiments achieves 85-95% when temperature is over 600 deg. C

  12. Performance of fluidized bed steam gasification of biomass - Modeling and experiment

    Energy Technology Data Exchange (ETDEWEB)

    Loha, Chanchal; Chatterjee, Pradip K. [Thermal Engineering Group, Central Mechanical Engineering Research Institute, CSIR, Durgapur 713 209 (India); Chattopadhyay, Himadri [Dept. of Mechanical Engineering, Jadavpur University, Kolkata 700 032 (India)

    2011-03-15

    This paper presents the investigation of the performance from different biomasses in a fluidized bed gasifier where steam has been used as gasifying as well as fluidizing agent. An experimental setup is fabricated to study the gasification performance of rice husk, which is of special relevance to rice-producing countries like China and India. An equilibrium modeling approach is deployed to predict the gas composition which has been compared with the experimental results. Calibration of the model with appropriate modeling coefficients was necessary to achieve close resemblance with the experimental values. Further, the model is used to predict the gas compositions from other biomass and benchmarked with the performance of coal. In this study, the gasification temperature is varied from 650 C to 800 C, whereas the steam-to-biomass ratio (S/B) is varied from 0.75 to 2.00. As the gasification temperature increases, the production of H{sub 2} and CO increases but the generation of CH{sub 4} and CO{sub 2} reduces. The steam-to-biomass ratio was again found to influence the production rates. With increasing steam input, H{sub 2}, CO{sub 2} and CH{sub 4} were found to increase while CO reduces. (author)

  13. Alkali retention/separation during bagasse gasification: a comparison between a fluidised bed and a cyclone gasifier

    Energy Technology Data Exchange (ETDEWEB)

    Gabra, M. [Lulea University of Technology (Sweden). Div. of Energy Engineering; Energy Technology Centre, Pitea (Sweden); Nordin, A. [Umea University (Sweden). Dept. of Inorganic Chemistry; Ohman, M. [Energy Technology Centre, Pitea (Sweden); Umea University (Sweden). Dept. of Inorganic Chemistry; Kjellstrom, B. [Lulea University of Technology (Sweden). Div. of Energy Engineering

    2001-12-01

    Biomass fuelled integrated gasification/gas turbines (BIG/GTS) have been found to be one of the most promising technologies to maximise electricity output in the sugar industry. However, biomass fuels contain alkali metals (Na and K) which may be released during the gasification processes and cause deleterious effects on the downstream hardware (e.g. the blades of gas turbines). Much research has therefore been focused on different kinds of gas cleaning. Most of these projects are using a fluidised bed gasifier and includes extensive gas cleaning which leads to a high capital investment. Increasing alkali retention/separation during the gasification may lead to improved producer gas quality and reduced costs for gas cleaning. However, very little quantitative information is available about the actual potential of this effect. In the present work, comparative bench-scale tests of bagasse gasification were therefore run in an isothermal fluidised bed gasifier and in a cyclone gasifier to evaluate which gasification process is most attractive as regards alkali retention/separation, and to try to elucidate the mechanisms responsible for the retention. The alkali retention in the fluidised bed gasifier was found to be in the range of 12-4% whereas in the cyclone gasifier the alkali separation was found to be about 70%. No significant coating of the fluidised bed's bed material particles could be observed. The SEM/EDS and the elemental maps of the bed material show that a non-sticky ash matrix consisting of mainly Si, AI and K were distributed in a solid form separated from the particles of bed material. This indicates the formation of a high temperature melting potassium containing silicate phase, which is continuously scavenged and lost from the bed through elutriation. (author)

  14. The Development of Ni/Dolomite Catalyst in Simultaneous Biomass Gasification and Reforming in Fluidized Bed

    Directory of Open Access Journals (Sweden)

    Anawat Ketcong

    2009-01-01

    Full Text Available Simultaneous gasification and steam reforming of the biomass on Ni/dolomite catalyst in fluidized bed reactor were studied in the gaseous production in the one stage reactor. Problem statement: The parameters such as temperature, steam flow rate, biomass feed rate, gas flow rate for fluidization, oxygen flow rate and catalyst types were studied to produce the high gaseous products including tar elimination. Approach: The temperature at 780°C, steam flow rate of 222 mmoL h-1, gas flow rate for fluidization 450 mL min-1 and oxygen input 50 mL min-1 were found to be the suitable conditions. The Ni/Dolomite and the developed Ni/Dolomite were studied about their performance. Results: It was confirmed that Ni/Dolomite and newly developed Ni-WO3/Dolomite show high performance in biomass gasification. Conclusion/Recommendations: It was claimed that Ni/Dolomite catalyst was the effective and give best performance for tar cracking. Newly developed Ni-WO3/Dolomite catalyst was investigated to resist sulfur nd coking. Three types of catalyst were used in the biomass gasification, which are Ni/Dolomite, Ni/Dolomite+Silica binder and Ni-WO3/Dolomite. From the XRD analysis, structures of type 1 (Ni/dolomite and type 2 (Ni/Dolomite+Silica binder were similar which were in CaCO3, MgNiO2, NiO and MgO forms. Type 3 (Ni-WO3/Dolomite was CaWO4, MgNiO2, NiO and MgO forms. When the catalytic gasification was operated, newly Ni- WO3/Dolomite catalyst was the best catalyst for bamboo and palm shell biomasses, which could produce the high carbon monoxide and hydrogen but low methane and carbon dioxide were found. Carbon deposition on catalyst was around 0.37 mg according to the TG analysis.

  15. Energy recovery from sewage sludge by means of fluidised bed gasification.

    Science.gov (United States)

    Gross, Bodo; Eder, Christian; Grziwa, Peter; Horst, Juri; Kimmerle, Klaus

    2008-01-01

    Because of its potential harmful impact on the environment, disposal of sewage sludge is becoming a major problem all over the world. Today the available disposal measures are at the crossroads. One alternative would be to continue its usage as fertiliser or to abandon it. Due to the discussions about soil contamination caused by sewage sludge, some countries have already prohibited its application in agriculture. In these countries, thermal treatment is now presenting the most common alternative. This report describes two suitable methods to directly convert sewage sludge into useful energy on-site at the wastewater treatment plant. Both processes consist mainly of four devices: dewatering and drying of the sewage sludge, gasification by means of fluidised bed technology (followed by a gas cleaning step) and production of useful energy via CHP units as the final step. The process described first (ETVS-Process) is using a high pressure technique for the initial dewatering and a fluidised bed technology utilising waste heat from the overall process for drying. In the second process (NTVS-Process) in addition to the waste heat, solar radiation is utilised. The subsequent measures--gasification, gas cleaning and electric and thermal power generation--are identical in both processes. The ETVS-Process and the NTVS-Process are self-sustaining in terms of energy use; actually a surplus of heat and electricity is generated in both processes. PMID:17919896

  16. Co-gasification of meat and bone meal with coal in a fluidised bed reactor

    Energy Technology Data Exchange (ETDEWEB)

    E. Cascarosa; L. Gasco; G. Gea; J.L. Sanchez; J. Arauzo [Universidad de Zaragoza (Spain). Thermochemical Processes Group

    2011-08-15

    After the Bovine Spongiform Encephalopathy illness appeared, the meat and bone meat (MBM) produced from animal residues became an important waste. In spite of being a possible fuel due to its heating value (around 21.4 MJ/kg), an important fraction of the meat and bone meal is being sent to landfills. The aim of this work is to evaluate the co-gasification of low percentages of meat and bone meal with coal in a fluidised bed reactor as a potential waste management alternative. The effect of the bed temperature (800-900{sup o}C), the equivalence ratio (0.25-0.35) and the percentage of MBM in the solid fed (0-1 wt.%) on the co-gasification product yields and properties is evaluated. The results show the addition of 1 wt.% of MBM in a coal gasification process increases the gas and the liquid yield and decreases the solid yield at 900{sup o}C and 0.35 of temperature and equivalence ratio operational conditions. At operational conditions of 900{sup o}C and equivalence ratio of 0.35, the specific yield to gas (y{sub gas}) increases from 3.18 m{sup 3}(STP)/kg to 4.47 m{sup 3}(STP)/kg. The gas energy yield decreased 24.1% and the lower heating value of the gas decreases from 3.36 MJ/m{sup 3}(STP) to 2.16 MJ/m{sup 3}(STP). The concentration of the main gas components (H{sub 2}, CO and CO{sub 2}) hardly varies with the addition of MBM, however the light hydrocarbon concentrations decrease and the H{sub 2}S concentration increases at the higher temperature (900{sup o}C). 32 refs., 9 figs., 7 tabs.

  17. The Influence of H2O and CO2 Addition to the Gasification Media during Oxyfuel Fluidized Bed Gasification of Biomass

    Czech Academy of Sciences Publication Activity Database

    Jeremiáš, Michal; Pohořelý, Michael; Kameníková, Petra; Skoblia, S.; Svoboda, Karel; Punčochář, Miroslav

    2010, VP2.1.12. ISBN N. [European Biomass Conference & Exhibition /18./. Lyon (FR), 03.05.2010-07.05.2010] R&D Projects: GA MŠk 2B08048 Grant ostatní: RFCR(XE) CT/2007/00005 Institutional research plan: CEZ:AV0Z40720504 Keywords : fluidized bed * gasification * biomass Subject RIV: CI - Industrial Chemistry, Chemical Engineering http://www.conference-biomass.com/

  18. Experimental study on catalytic steam gasification of municipal solid waste for bioenergy production in a combined fixed bed reactor

    International Nuclear Information System (INIS)

    The catalytic steam gasification of municipal solid waste (MSW) for hydrogen-rich fuel gas production was experimentally investigated in a combined fixed bed reactor using the newly developed tri-metallic catalyst. The results indicated that the supported tri-metallic catalyst had a high activity of cracking tar and hydrocarbons, upgrading the gas quality, as well as yielding a high hydrogen production in catalytic steam gasification of municipal solid waste. A series of experiments have been performed to explore the effects of catalyst presence, catalyst to MSW mass ratio (C/M), catalytic temperature, steam to MSW ratio (S/M) and MSW particle size on the composition and yield of gasification gases. The experiments demonstrated that temperature was the most important factor in this process; higher temperature contributed to more hydrogen production and gas yield. Varying catalyst to MSW mass ratio (C/M) demonstrated complex effects on gas yield and composition of MSW gasification and an optimal value of 0.5 was found in the present study. Comparing with MSW catalytic gasification, the introduction of steam improved gas quality and yield, the optimal value of S/M was found to be 1.33 under the present operating condition. It was also shown that a smaller particle size was more favorable for gas quality and yield. -- Highlights: ► The catalytic steam gasification of MSW was experimentally investigated in a fixed bed reactor. ► The effects of operating conditions on gas yield and composition of MSW gasification were explored. ► The NiLaFe/γ-Al2O3 catalyst had a high activity of cracking tar and upgrading the gas quality. ► The optimal operating parameters for catalytic steam gasification of MSW were found in this paper.

  19. The formation of impurities in fluidized-bed gasification of biomass, peat and coal; Epaepuhtauksien muodostuminen leijukerroskaasutuksessa

    Energy Technology Data Exchange (ETDEWEB)

    Kurkela, E.; Laatikainen-Luntama, J.; Kurkela, M.; Leppaelahti, J.; Koljonen, T.; Oesch, P. [VTT Energy, Espoo (Finland); Alen, R. [Jyvaeskylae Univ. (Finland)

    1996-12-01

    The objective of this three-year-long project was to study the effects of different process parameters and bed materials on the formation of impurities in pressurized fluidized-bed gasification. The main emphasis of the project was focused on the formation of tars and nitrogen compounds in wood, peat and coal gasification. The aims of the research were to find out such operating conditions, where the formation of problematic high-molecular-weight tars can be minimised and to create a better understanding on the fate of fuel nitrogen in fluidized-bed gasifiers. Main part of the research was carried out in a bench-scale pressurised fluidized-bed reactor (ID 30 mm), where the effects of pressure, temperature, gas atmosphere and bed material were studied with different feedstocks. Most of the test series were carried out using the same feedstocks as earlier used in the PDU-scale fluidized-bed gasification tests of VTT (pine wood, pine bark, wheat straw, two peats, Rhenish brown coal, Polish and Illinois No.6 bituminous coals). The effects of operating parameters on the product yields (gas components, tars, char) were first studied under inert nitrogen atmosphere. The conversion of fuel nitrogen into ammonia and HCN were also determined for the different feedstocks over the different operating conditions. These studies showed that ammonia is the main fixed nitrogen compound of fluidized-bed pyrolysis with all the feedstocks studied. The conversions of fuel nitrogen into ammonia and HCN was highest with the high volatile fuels and lowest with the two hard coals. Gas atmosphere had a dramatic effect on the conversion of fuel nitrogen; much higher ammonia yields were determined in real gasification gas atmosphere than in inert pyrolysis carried out in N{sub 2} or Argon atmosphere. In addition to the pressurised fluidized-bed pyrolysis tests, laboratory scale pyrolysis research was carried out in order to compare the pyrolysis behaviour of the different feedstocks

  20. CHEMICALLY ACTIVE FLUID-BED PROCESS FOR SULPHUR REMOVAL DURING GASIFICATION OF HEAVY FUEL OIL - SECOND PHASE

    Science.gov (United States)

    The report describes the second phase of studies on the CAFB process for desulfurizing gasification of heavy fuel oil in a bed of hot lime. The first continuous pilot plant test with U.S. limestone BCR 1691 experienced local stone sintering and severe production of sticky dust du...

  1. Energy generation by air gasification of two industrial plastic wastes in a pilot scale fluidized bed reactor

    International Nuclear Information System (INIS)

    Two plastic wastes obtained as co-products from an industrial process were fed in a pilot-scale bubbling fluidized bed gasifier, having an internal diameter of 0.38 m and a maximum thermal output of about 400 kW. The experimental runs were carried out by reaching a condition of thermal and chemical steady state under values of equivalence ratio ranging from 0.2 to 0.3. Olivine, a neo-silicate of Fe and Mg, already tested as a good catalyst for tar removal during gasification of polyolefin plastic wastes, was used as bed material. The results provide the complete composition of the syngas, including the tar, particulate and acid/basic gas contents as well as the chemical and physical characterization of the bed material and entrained fines. The gasification process appears technically feasible, yielding a producer gas of valuable quality for energy applications in an appropriate plant configuration. On the other hand, under the experimental conditions tested, olivine particles show a strongly reduced catalytic activity in all the runs. The differences in the gasification behaviour of the two industrial plastics are explained on the basis of the structure and composition of the wastes, taking also into account the results of a combined material and substance flow analysis. - Highlights: • Pilot-scale investigation of fluidized bed gasification of two industrial plastic wastes. • Tests under conditions of thermal/chemical steady state at various equivalence ratios. • Complete composition of the producer gas, including tar, particulate and acid/basic gases. • Differences in the gasification behaviour of plastic wastes. • Material, substance, and feedstock energy flow analysis for different gasification tests

  2. Gasification of hay in a bench scale fluidised bed reactor with emphasis on the suitability for gas turbines

    International Nuclear Information System (INIS)

    Thermal gasification of pasture plants (hay) is so far considered as difficult mainly due to the high amount of inorganics (ash, alkalis). Under certain circumstances it could be an additional resource for power production. There has been some experiments to test hay in gasification plants but most lack inorganic analysis. A bubbling fluidized bed was set up and gasification experiments with extensive analysis of the gas composition was conducted. Dolomite, silica and alumina particles were used as bed material. Silica proved to work successfully at 700 °C. Ash experiments showed that at higher temperatures silica forms compounds that melt and lead to unstable gasification conditions. Dolomite proved to be not stable enough for fluidised bed conditions, since it was ground down to smaller particles and subsequently entrained. Alumina was the best bed material tested, which was used up to 750 °C with good results. The longest run was 10 h at 750 °C without defluidisation. Despite the low temperature in the process the bulk tar concentration was low. The heating value of the gas was good (4–6 MJ m−3). The concentration of sodium and potassium in the syngas after the warm gas filter at 400 °C is low enough towards a cofiring IGCC application with 10% energy input from hay. -- Highlights: ► Stable gasification of hay in a fluidised bed could be established. ► Corrosion promoting contaminants were successfully measured. ► Axial profile measurements of permanent gases are reported. ► Axial profile of the evolution of the volume flow is reported.

  3. Effect of Operating Conditions on Catalytic Gasification of Bamboo in a Fluidized Bed

    Directory of Open Access Journals (Sweden)

    Thanasit Wongsiriamnuay

    2013-01-01

    Full Text Available Catalytic gasification of bamboo in a laboratory-scale, fluidized bed reactor was investigated. Experiments were performed to determine the effects of reactor temperature (400, 500, and 600°C, gasifying medium (air and air/steam, and catalyst to biomass ratio (0 : 1, 1 : 1, and 1.5 : 1 on product gas composition, H2/CO ratio, carbon conversion efficiency, heating value, and tar conversion. From the results obtained, it was shown that at 400°C with air/steam gasification, maximum hydrogen content of 16.5% v/v, carbon conversion efficiency of 98.5%, and tar conversion of 80% were obtained. The presence of catalyst was found to promote the tar reforming reaction and resulted in improvement of heating value, carbon conversion efficiency, and gas yield due to increases in H2, CO, and CH4. The presence of steam and dolomite had an effect on the increasing of tar conversion.

  4. Process performance improvement in a co-current, fixed bed biomass gasification facility by control system modifications

    International Nuclear Information System (INIS)

    Highlights: • Software algorithms for biomass gasification process improvement have been developed. • Advanced control solution has been proposed for on-line process control. • Different process variables have been controlled simultaneously. • Different process improvement cases have been analysed. • Data for system development has been extracted from co-current, fixed bed gasifier. - Abstract: Advanced control solutions are a developing technology which represent a promising approach to tackle problems related to efficiency and environmental aspects of biomass gasification process in a cost effective way. In this paper the potential of advanced control concept to improve gasification process efficiency and to reduce negative environmental effects of the process has been analysed. Advanced control solution, based on feedforward–feedback control approach has been developed using collected operation data and the effects of control concept on gasification process have been analysed using developed artificial neural network based prediction model. Measurement data for the controller and simulation model development has been extracted from a 75 MWth co-current, fixed bed biomass gasification plant operated by Technical University Dresden. The effects of 6 different process improvement goals for controller algorithms development have been analysed during 20 h of plant operation. The analysis has shown that with introduction of advanced control solutions process efficiency could be improved up to 20%, together with reduction of negative environmental aspects of the process

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1994-07-05

    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.

  6. Biomass gasification in a circulating fluidized bed; Vergasung von Biomasse in der zirkulierenden Wirbelschicht

    Energy Technology Data Exchange (ETDEWEB)

    Ising, M.; Hoelder, D.; Backhaus, C.; Althaus, W. [Fraunhofer Inst. fuer Umwelt-, Sicherheits- und Energietechnik UMSICHT, Oberhausen (Germany)

    1998-09-01

    Biomass gasification in a circulating fluidized bed, in combination with a gas engine or gas burner, is a promising option for energetic use of biomass. Economic efficiency analyses on the basis of the UMSICHT plant show that this technology for combined heat and power generation from biomass is promising also for the range below 10 MW. The economic situation of any plant must be considered for the specific boundary conditions imposed by the power supply industry. The feasibility of the process was tested in a demonstration plant at Oberhausen. The plant was optimized further in extensive test series, and a number of tar reduction processes were investigated and improved on. The authors now intend to prove that gasification in a circulating fluidized bed combined with a gas engine cogeneration plant is feasible in continuous operation. (orig./SR) [Deutsch] Die Vergasung von Biomasse in der zirkulierenden Wirbelschicht ist in Kombination mit einem Gasmotor oder einem Gasbrenner eine vielversprechende Option fuer die energetische Biomassenutzung. Wirtschaftlichkeitsbetrachtungen auf Basis der UMSICHT-Anlage zeigen, dass diese Technologie fuer die gekoppelte Strom- und Waermeerzeugung aus Biomasse auch im Leistungsbereich unter 10 MW grosse Chancen verspricht. Dabei ist die oekonomische Situation einer Anlage im Einzelfall unter Beachtung der energiewirtschaftlichen Randbedingungen zu beurteilen. Durch den Betrieb einer Demonstrationsanlage in Oberhausen konnte die Funktion des Verfahrens nachgewiesen werden. In weiteren umfangreichen Versuchsreihen werden die Anlage weiter optimiert und verschiedene Konzepte zur Teerminderung untersucht und weiterentwickelt. Angestrebt ist der Nachweis des Dauerbetriebs von ZWS-Vergasung zusammen mit dem Gasmotoren-BHKW. (orig./SR)

  7. Influence of particle size on pyrolysis and gasification performance of municipal solid waste in a fixed bed reactor.

    Science.gov (United States)

    Luo, Siyi; Xiao, Bo; Hu, Zhiquan; Liu, Shiming; Guan, Yanwen; Cai, Lei

    2010-08-01

    Pyrolysis and gasification of municipal solid waste (MSW) were carried out in a lab-scale fixed bed reactor in order to evaluate the effects of particle size at different bed temperatures on product yield and composition. The bed temperature was varied from 600 to 900 degrees C and the MSW was separated into three different size fractions (below 5 mm, 50-10 mm and above 10 mm). Particle size and temperature had integrated effects on product yield and composition: higher temperature resulted in higher gas yield with less tar and char, and, at the same temperature, dry gas yield increased with a decrease in particle size, and char and tar yield decreased. The differences due to particle sizes in pyrolysis and gasification performance practically disappeared at the highest temperatures tested. Smaller particle sizes resulted in higher H(2) and CO contents for both pyrolysis and gasification of MSW. Minimizing the size of raw materials is an alternative method to improve the gas quality of MSW pyrolysis and gasification. PMID:20363619

  8. Potential approaches to improve gasification of high water content biomass rich in cellulose in dual fluidized bed

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Li; Xu, Guangwen [State Key Laboratory of Multiphase Complex System, Institute of Process Engineering, Chinese Academy of Sciences, Beijing (China); Suda, Toshiyuki [Research Laboratory, IHI Corporation, Ltd., Yokohama (Japan); Murakami, Takahiro [National Institute of Advanced Science and Technology, Tsukuba (Japan)

    2010-08-15

    Biomass containing water of 30-65 wt.% and rich in cellulose, such as various grounds of drinking materials and the lees of spirit and vinegar, is not suitable for biological digestion, and the thermal conversion approach has to be applied to its conversion into bioenergy. The authors have recently worked on converting such biomass into middle heating-value gas via dual fluidized bed gasification (DFBG) integrated with various process intensification technologies. This article is devoted to highlighting those technical ways, including the choice of the superior technical deployment for a DFBG system, the impregnation of Ca onto fuel in fuel drying, the integration of gas cleaning with fuel gasification via two-stage DFBG (T-DFBG), and the decoupling of fuel drying/pyrolysis and char gasification via the decoupled DFBG (D-DFBG). The attained results demonstrated that the superior deployment of bed combination for the DFBG should be a bubbling/turbulent fluidized bed gasifier integrated with a pneumatic riser combustor. In terms of improving efficiency of fuel conversion into combustible gas and suppressing tar generation during gasification, the impregnation of Ca onto fuel exhibited distinctively high upgrading effect, while both the T-DFBG and D-DFBG were also demonstrated to be effective to a certain degree. (author)

  9. Two stage fluid bed-plasma gasification process for solid waste valorisation: technical review and preliminary thermodynamic modelling of sulphur emissions.

    OpenAIRE

    Morrin, S.; Lettieri, P.; Chapman, C.; Mazzei, L

    2011-01-01

    Gasification of solid waste for energy has significant potential given an abundant feed supply and strong policy drivers. Nonetheless, significant ambiguities in the knowledge base are apparent. Consequently this study investigates sulphur mechanisms within a novel two stage fluid bed-plasma gasification process. This paper includes a detailed review of gasification and plasma fundamentals in relation to the specific process, along with insight on MSW based feedstock properties and sulphur po...

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

    Science.gov (United States)

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

    2016-08-01

    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.

  11. Computational simulation of the biomass gasification process in a fluidized bed reactor

    International Nuclear Information System (INIS)

    In an agro-industrial country as Cuba many residues of cultivation like the rice and the cane of sugar take place, besides the forest residues in wooded extensions. Is an interesting application for all this biomass, the gasification technology, by its high efficiency and its positive environmental impact. The computer simulation appears like a useful tool in the researches of parameters of operation of a gas- emitting, because it reduces the number of experiments to realise and the cost of the researches. In the work the importance of the application of the computer simulation is emphasized to anticipate the hydrodynamic behavior of fluidized bed and of the process of combustion of the biomass for different residues and different conditions of operation. A model using CFD for the simulation of the process of combustion in a gas- emitting of biomass sets out of fluidized bed, the hydrodynamic parameters of the multiphasic flow from the elaboration of a computer simulator that allows to form and to vary the geometry of the reactor, as well as the influence of the variation of magnitudes are characterized such as: speed, diameter of the sand and equivalent reason. Experimental results in cylindrical channels appear, to complete the study of the computer simulation realised in 2D. (author)

  12. A techno-economic comparison of fluidized bed gasification of two mixed plastic wastes.

    Science.gov (United States)

    Arena, U; Di Gregorio, F; Amorese, C; Mastellone, M L

    2011-07-01

    A comparison between the most promising design configurations for the industrial application of gasification based, plastics-to-energy cogenerators in the 2-6 MWe range is presented. A pilot scale bubbling fluidized bed air gasifier, having a feeding capacity of 100 kg/h, provided experimental data: the syngas complete composition, the characterization of the bed material, the entrained fines collected at the cyclone and the purge material from the scrubber. Mass and energy balances and material and substance flow analyses have been therefore drawn to assess and compare design solutions utilizing two mixed plastic wastes (MPW) obtained from separate collection of plastic packaging, after different levels of pre-treatments. The related techno-economic performances have been finally estimated on the basis of the manufacturer's specifications. The study concludes that the MPW obtained after a very simple pre-treatment and fed to a gasifier coupled with a steam turbine is the solution that currently offers the higher reliability and provides the higher internal rate of return for the investigated range of electrical energy production. PMID:21377344

  13. Gasification of leached orujillo (olive oil waste) in a pilot plant circulating fluidised bed reactor. Preliminary results

    International Nuclear Information System (INIS)

    Nearly a quarter of the world's olive oil production takes place in Spain, where energy companies are starting to exploit the potential of the residues from this industry as biomass fuel for energy production. Approximately, 2 million t/yr of orujillo (a residual by-product of the olive oil production industry) are generated in Spain. Fluidised bed gasification is considered to be the most advanced method for thermochemical conversion of various biomass fuels to energy. Ash-related problems such as sintering, agglomeration, deposition, erosion and corrosion, which are due to the low melting point of ash in the agroresidues, are the main obstacles for economical and viable application of this conversion method for energy exploitation of the specific residues. The leaching (washing) of inorganic constituents from biomass leads to changes in inorganic composition and substantial improvements in ash thermal behaviour under gasification conditions. Leached orujillo has been tested in a 300 kWth atmospheric circulating fluidised-bed (CFB) gasification facility using air as a fluidisation agent. In this paper, the effect of experimental conditions on gasification process with the aim of enhancing the gas production and improving its composition and energetic content was analysed. The first tests have demonstrated that the CFB test rig operates adequately and makes it possible to carry out gasification experiments with orujillo as a fuel. The lower heating value of the producer gas obtained is 3.8 MJ/Nm3 at the lowest temperature (780 deg. C). The carbon conversion in orujillo gasification at the 800 deg. C set points was in the range of 81.0-86.9%. The increase in equivalence ratio did not improve carbon conversion significantly. The gas yield increases when equivalence ratio increases

  14. Partial oxidation of sewage sludge briquettes in a updraft fixed bed.

    Science.gov (United States)

    Kim, Minsu; Lee, Yongwoon; Park, Jinje; Ryu, Chankook; Ohm, Tae-In

    2016-03-01

    The fixed bed reaction of sewage sludge briquettes was investigated to evaluate the potential applications to gasification, combustion, or production of biochar as soil ameliorator. The reaction had two distinctive stages: ignition propagation and char oxidation. The ignition front of the sludge briquettes propagated at a lower speed, which significantly increased the stoichiometric ratio of overall combustion reaction and peak temperatures. The ignition front also had irregular shapes due to the channeling effects. During the char oxidation stage, the sludge ash agglomerated because of the slow reaction rate and increased CO2 formation. Because of low energy content in the product gas, the large briquettes were not favorable for syngas production. In addition, the low burning rates and ash agglomeration could cause problems in the operation of a grate-type furnace for combustion. However, the char accumulated above the ignition front had similar properties with that from pyrolysis under inert atmosphere. Therefore, the fixed bed reaction under partial oxidation conditions can be applied to produce biochar as soil ameliorator from the sludge briquettes without external heat supply. PMID:26860426

  15. Semi-continuous feeding and gasification of alfalfa and wheat straw pellets in a lab-scale fluidized bed reactor

    International Nuclear Information System (INIS)

    Highlights: • Alfalfa and wheat straw pellets were gasified in a lab-scale fluid-bed reactor. • ER varied between 0.20 and 0.35 at which several parameters investigated. • ER = 0.35 was found optimum for alfalfa at which process performance improved. • ER = 0.30 revealed optimum for wheat straw at which gasification was effective. - Abstract: Small scale air-blown fluidized bed gasification of alfalfa and wheat straw pellets were conducted for semi-continuous solid feeding and range of operating conditions varied due to the modifications in equivalence ratio (ER) (0.20–0.35) achieved both by varying solid and air input. Alfalfa pellets displayed an improvement in several gasification variables such as gas lower heating value (∼4.1 MJ/Nm3), specific gas yield (1.66 Nm3/kg), cold gas efficiency (∼42%) and carbon conversion efficiency (∼72%) as ER maximized to 0.35 which was found optimum for this feedstock for the present course of experiments. Gasification parameters of wheat straw pellets on the other hand were characterized by a great degree of variation as the ER progressively increased. The optimum performance of this biomass was likely to achieve at ER = 0.30 when gas lower heating value and cold gas efficiency maximized to ∼4 MJ/Nm3 and ∼37% respectively. Moreover, a substantial drop in tar yield (58.7 g/Nm3) at this ER was also indicative to the optimal thermal conversion at this point of operation. Overall, both the feedstocks presented promising alternatives for utilization into the small-scale fluidized bed gasification which is increasingly emerging as a sustainable solution towards processing lignocellulosic biomass

  16. Liquid transportation fuels via large-scale fluidised-bed gasification of lignocellulosic biomass

    Energy Technology Data Exchange (ETDEWEB)

    Hannula, I.; Kurkela, E.

    2013-04-15

    With the objective of gaining a better understanding of the system design trade-offs and economics that pertain to biomass-to-liquids processes, 20 individual BTL plant designs were evaluated based on their technical and economic performance. The investigation was focused on gasification-based processes that enable the conversion of biomass to methanol, dimethyl ether, Fischer-Tropsch liquids or synthetic gasoline at a large (300 MWth of biomass) scale. The biomass conversion technology was based on pressurised steam/O2-blown fluidised-bed gasification, followed by hot-gas filtration and catalytic conversion of hydrocarbons and tars. This technology has seen extensive development and demonstration activities in Finland during the recent years and newly generated experimental data has also been used in our simulation models. Our study included conceptual design issues, process descriptions, mass and energy balances and production cost estimates. Several studies exist that discuss the overall efficiency and economics of biomass conversion to transportation liquids, but very few studies have presented a detailed comparison between various syntheses using consistent process designs and uniform cost database. In addition, no studies exist that examine and compare BTL plant designs using the same front-end configuration as described in this work. Our analysis shows that it is possible to produce sustainable low-carbon fuels from lignocellulosic biomass with first-law efficiency in the range of 49.6-66.7% depending on the end-product and process conditions. Production cost estimates were calculated assuming Nth plant economics and without public investment support, CO2 credits or tax assumptions. They are 58-65 euro/MWh for methanol, 58-66 euro/MWh for DME, 64-75 euro/MWh for Fischer-Tropsch liquids and 68-78 euro/MWh for synthetic gasoline. (orig.)

  17. Porous filtering media comparison through wet and dry sampling of fixed bed gasification products

    International Nuclear Information System (INIS)

    The syngas produced by fixed bed gasifiers contains high quantities of particulate and tars. This issue, together with its high temperature, avoids its direct exploitation without a proper cleaning and cooling process. In fact, when the syngas produced by gasification is used in an Internal Combustion engine (IC), the higher the content of tars and particulate, the higher the risk to damage the engine is. If these compounds are not properly removed, the engine may fail to run. A way to avoid engine fails is to intensify the maintenance schedule, but these stops will reduce the system profitability. From a clean syngas does not only follow higher performance of the generator, but also less pollutants in the atmosphere. When is not possible to work on the gasification reactions, the filter plays the most important role in the engine safeguard process. This work is aimed at developing and comparing different porous filters for biomass gasifiers power plants. A drum filter was developed and tested filling it with different filtering media available on the market. As a starting point, the filter was implemented in a Power Pallet 10 kW gasifier produced by the California-based company ''ALL Power Labs''. The original filter was replaced with different porous biomasses, such as woodchips and corn cobs. Finally, a synthetic zeolites medium was tested and compared with the biological media previously used. The Tar Sampling Protocol (TSP) and a modified ''dry'' method using the Silica Gel material were applied to evaluate the tars, particulate and water amount in the syngas after the filtration process. Advantages and disadvantages of every filtering media chosen were reported and discussed

  18. CO-PRODUCTION OF HYDROGEN AND ELECTRICITY USING PRESSURIZED CIRCULATING FLUIDIZED BED GASIFICATION TECHNOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    Zhen Fan

    2006-05-30

    Foster Wheeler has completed work under a U.S. Department of Energy cooperative agreement to develop a gasification equipment module that can serve as a building block for a variety of advanced, coal-fueled plants. When linked with other equipment blocks also under development, studies have shown that Foster Wheeler's gasification module can enable an electric generating plant to operate with an efficiency exceeding 60 percent (coal higher heating value basis) while producing near zero emissions of traditional stack gas pollutants. The heart of the equipment module is a pressurized circulating fluidized bed (PCFB) that is used to gasify the coal; it can operate with either air or oxygen and produces a coal-derived syngas without the formation of corrosive slag or sticky ash that can reduce plant availabilities. Rather than fuel a gas turbine for combined cycle power generation, the syngas can alternatively be processed to produce clean fuels and or chemicals. As a result, the study described herein was conducted to determine the performance and economics of using the syngas to produce hydrogen for sale to a nearby refinery in a hydrogen-electricity co-production plant setting. The plant is fueled with Pittsburgh No. 8 coal, produces 99.95 percent pure hydrogen at a rate of 260 tons per day and generates 255 MWe of power for sale. Based on an electricity sell price of $45/MWhr, the hydrogen has a 10-year levelized production cost of $6.75 per million Btu; this price is competitive with hydrogen produced by steam methane reforming at a natural gas price of $4/MMBtu. Hence, coal-fueled, PCFB gasifier-based plants appear to be a viable means for either high efficiency power generation or co-production of hydrogen and electricity. This report describes the PCFB gasifier-based plant, presents its performance and economics, and compares it to other coal-based and natural gas based hydrogen production technologies.

  19. Direct Causticizing for Black Liquor Gasification in a Circulating Fluidized Bed

    Energy Technology Data Exchange (ETDEWEB)

    Scott Sinquefield; Xiaoyan Zeng, Alan Ball

    2010-03-02

    Gasification of black liquor (BLG) has distinct advantages over direct combustion in Tomlinson recovery boilers. In this project we seek to resolve causticizing issues in order to make pressurized BLG even more efficient and cost-effective. One advantage of BLG is that the inherent partial separation of sulfur and sodium during gasification lends itself to the use of proven high yield variants to conventional kraft pulping which require just such a separation. Processes such as polysulfide, split sulfidity, ASAQ, and MSSAQ can increase pulp yield from 1% to 10% over conventional kraft but require varying degrees of sulfur/sodium separation, which requires additional [and costly] processing in a conventional Tomlinson recovery process. However during gasification, the sulfur is partitioned between the gas and smelt phases, while the sodium all leaves in the smelt; thus creating the opportunity to produce sulfur-rich and sulfur-lean white liquors for specialty pulping processes. A second major incentive of BLG is the production of a combustible product gas, rich in H2 and CO. This product gas (a.k.a. “syngas”) can be used in gas turbines for combined cycle power generation (which is twice as efficient as the steam cycle alone), or it can be used as a precursor to form liquid fuels, such as dimethyl ether or Fischer Tropsh diesel. There is drawback to BLG, which has the potential to become a third major incentive if this work is successful. The causticizing load is greater for gasification of black liquor than for combustion in a Tomlinson boiler. So implementing BLG in an existing mill would require costly increases to the causticizing capacity. In situ causticizing [within the gasifier] would handle the entire causticizing load and therefore eliminate the lime cycle entirely. Previous work by the author and others has shown that titanate direct causticizing (i.e. in situ) works quite well for high-temperature BLG (950°C), but was limited to pressures below

  20. Mineralogy of fixed-bed gasification ash derived from North Dakota lignite

    International Nuclear Information System (INIS)

    The mineralogy of nine ash samples derived from North Dakota lignite and gasified in three different fixed-bed producers was determined by x-ray diffraction (XRD) and scanning electron microscopy (SEM). The gasifiers had maximum temperatures in the 1100-12500C range, but included several differences in ash residence time, oxidizing gas and pressure, and ash handling conditions. The lignite gasified came from the same geologic formation, but the mines were separated by 20 km. Despite these differences, all of the ash specimens has the same basic mineralogy: glass at the 15-30 wt.% level; a crystalline phase assemblage of ortho- and pyro-silicates (merwinite, di-calcium silicate (C/sub 2/S), C/sub 2/S- like phases, and melilite), network aluminosilicates (nepheline, carnegieite, and a sodalite-structure phase), oxides (ferrite spinel, hematite, and periclase), and calcite along with residual lignite minerals (quartz and felspar). SEM morphologies and XRD comparisons of the amounts of crystalline phases in size fractions both indicated that some of the phases (particularly merwinite and carnegieite) crystallized during cooling of portions of the ash that had melted during gasification

  1. Gasification of Biochar from Empty Fruit Bunch in a Fluidized Bed Reactor

    Directory of Open Access Journals (Sweden)

    M. A. Mohd Salleh

    2010-07-01

    Full Text Available A biochar produced from empty fruit bunches (EFB was gasified in a fluidized bed using air to determine gas yield, overall carbon conversion, gas quality, and composition as a function of temperature. The experiment was conducted in the temperature range of 500–850 °C. It was observed that biochar has the potential to replace coal as a gasification agent in power plants. Hydrogen gas from biochar was also optimized during the experiment. High temperatures favor H2 and CO formation. There was an increase of H2 over the temperature range from 500–850 °C from 5.53% to 27.97% (v/v, with a heating value of 30 kJ/g. The C conversion in the same temperature range increased from 76% to 84%. Therefore, there are great prospects for the use of biochar from EFB as an alternative fuel in power plants, as a renewable energy providing an alternative path to biofuels. Results from this work enable us to better understand syn gas production under high treatment temperatures.

  2. Gasification of biochar from empty fruit bunch in a fluidized bed reactor

    Energy Technology Data Exchange (ETDEWEB)

    Mohd Salleh, M. A.; Hussein Kisiki, N.; Yusuf, H. M.; Ghani, W. A. K. [Department of Chemical and Enviromental Engineering University Putra Malaysia, 43400, Serdang (Malaysia)

    2010-07-15

    A biochar produced from empty fruit bunches (EFB) was gasified in a fluidized bed using air to determine gas yield, overall carbon conversion, gas quality, and composition as a function of temperature. The experiment was conducted in the temperature range of 500-850 {sup o}C. It was observed that biochar has the potential to replace coal as a gasification agent in power plants. Hydrogen gas from biochar was also optimized during the experiment. High temperatures favor H{sub 2} and CO formation. There was an increase of H{sub 2} over the temperature range from 500-850 {sup o}C from 5.53% to 27.97% (v/v), with a heating value of 30 kJ/g. The C conversion in the same temperature range increased from 76% to 84%. Therefore, there are great prospects for the use of biochar from EFB as an alternative fuel in power plants, as a renewable energy providing an alternative path to biofuels. Results from this work enable us to better understand syn gas production under high treatment temperatures. (authors)

  3. Effect of temperature and dolomite on tar formation during gasification of torrefied biomass in a pressurized fluidized bed

    International Nuclear Information System (INIS)

    This work investigates the effect of temperature and bed material on the yields and composition of gas and tar produced from gasification of two types of biomass feedstock previously torrefied at 275 °C. Special attention was devoted to the evolution of tar composition under the different experimental conditions. Experiments were conducted in a fluidized bed reactor using two different types of bed material (sand and dolomite) under a constant pressure of 0.5 MPa and at two temperature levels (750 and 850 °C). Tar destruction reactions promoted by the catalyst (dolomite) enhanced the production of some of the gas components (H2, CO2, CO and CH4) whereas C2 hydrocarbons decreased, this effect being slightly more relevant at 850 °C. Comparable trends were observed with increasing temperature, which had a positive effect on cracking reactions and tar destruction. For both feedstocks, the increase in temperature resulted in (i) higher gas yields, and (ii) enhanced char gasification rate. On the other hand the evolution of tar yield and composition revealed a possible competition between two tar reaction pathways during gasification, (i) tar polymerization, and (ii) de-alkylation, dehydration and cracking of tars, depending on the experimental conditions and feedstock used. - Highlights: • An experimental study of pressurized gasification of torrefied biomass is presented. • Special attention was devoted to the evolution of tar composition. • Increasing temperature and dolomite presence led to higher gas and lower tar yields. • Tar evolution revealed a possible competition between two tar reaction pathways

  4. Stoichiometric, mass, energy and exergy balance analysis of countercurrent fixed-bed gasification of post-consumer residues

    International Nuclear Information System (INIS)

    Air-blown gasification studies were conducted on a countercurrent fixed-bed gasifier for municipal residue-based Refuse Derived Fuel (RDF) pellets and compared with the mass and energy performance features of gasifier with other biomass and residual fuels. The mass conversion efficiency and cold gas efficiency (CGE) of the gasifier were observed to be 83% and 73%, respectively for RDF pellets. The higher heating value and global energy content of the producer gas generated from gasification of RDF pellets was observed to be 5.58 MJ Nm-3 and 12.2 MJ kg-1, respectively. The tar content in the gas generated from RDF pellets was observed to be about 45% less than the tar content in the gas generated from wood chips (WC). Empirical stoichiometric equations were developed to describe the gasification of different fuels. A complete thermodynamic analysis was performed to determine the magnitudes of various inefficiencies and irreversibilities involved in the process. It was evaluated for RDF pellets that 27% of the exergy or available energy input was dissipated in the system due to various irreversibilities taking place in the gasification process. The second law CGE was observed to be highest for RDF pellets i.e. 56% followed by charred soybean straw pellets and WC. Thermal energy in the form of sensible heat energy accounted for 6-7% of the total energy; the available energy accounted for 2-3% of the total energy output of the process

  5. Bed Agglomeration During the Steam Gasification of a High Lignin Corn Stover Simultaneous Saccharification and Fermentation (SSF) Digester Residue

    Energy Technology Data Exchange (ETDEWEB)

    Howe, Daniel T.; Taasevigen, Danny J.; Gerber, Mark A.; Gray, Michel J.; Fernandez, Carlos A.; Saraf, Laxmikant; Garcia-Perez, Manuel; Wolcott, Michael P.

    2015-11-13

    This research investigates the bed agglomeration phenomena during the steam gasification of a high lignin residue produced from the simultaneous saccharification and fermentation (SSF) of corn stover in a bubbling fluidized bed. The studies were conducted at 895°C using alumina as bed material. Biomass was fed at 1.5 kg/hr, while steam was fed to give a velocity equal to 2.5 times the minimum fluidization velocity, with a steam/carbon ratio of 0.9. The pelletized feedstock was co-fed with a cooling nitrogen stream to mitigate feed line plugging issues. Tar production was high at 50.3 g/Nm3, and the fraction of C10+ compounds was greater than that seen in the gasification of traditional lignocellulosic feedstocks. Carbon closures over 94 % were achieved for all experiments. Bed agglomeration was found to be problematic, indicated by pressure drop increases observed below the bed and upstream of the feed line. Two size categories of solids were recovered from the reactor, +60 mesh and -60 mesh. After a 2.75-hour experiment, 61.7 wt % was recovered as -60 mesh particles and 38.2 wt% of the recovered reactor solids were +60 mesh. A sizeable percentage, 31.8 wt%, was +20 mesh. The -60 mesh particles were mainly formed by the initial bed material (Al2O3). Almost 50 wt. % of the + 20 mesh particles was found to be formed by organics. The unreacted carbon remaining in the reactor resulted in a low conversion rate to product gas. ICP-AES, SEM, SEM-EDS, and XRD confirmed that the large agglomerates (+ 20 mesh) were not encapsulated bed material but rather un-gasified feedstock pellets with sand particles attached to it.

  6. The characterisation of tars produced during the gasification of sewage sludge in a spouted bed reactor

    Energy Technology Data Exchange (ETDEWEB)

    A. Adegoroye; N. Paterson; X. Li; T. Morgan; A.A. Herod; D.R. Dugwell; R. Kandiyoti [Imperial College London, London (United Kingdom). Chemical Engineering

    2004-10-01

    Tars released by the gasification of sewage sludge in a spouted bed gasifier have been collected, quantified and characterised. The amounts collected were low which shows that the volatiles contained in the feedstock were cracked efficiently under the conditions in the gasifier. The presence of a high concentration of steam in the gasifying medium enhanced the conversion further. Within the 760-980{sup o}C range, the amount present did not show any variation with temperature of formation. GC/MS of a limited number of samples showed that the tars it had an aromatic character, as expected at the temperatures used. Approximately, 60-70% of the tars evaporated below 450{sup o}C. Thermogravimetric analysis of the tar-trap samples has allowed an estimation of the boiling point distributions of the samples. For the majority of the tar samples, from both types of sewage, between 60 and 70% of the tar boiled at {lt} 450{sup o}C. The Biogran tar exhibited a trend of an increase in the {lt} 250{sup o}C fraction and an increase in the {gt} 450{sup o}C fraction, with increasing temperature of formation. The Danish tar-trap samples showed a decreasing trend in both fractions with increasing temperature. These data give an indication of the way the tars progressively break down under the gasifier conditions and implies that steam can have an impact on the reaction pathway. Changes in the composition of the tars with temperature were also identified using size exclusion chromatography (SEC) and by ultra violet fluorescence spectroscopy (UV-F). 21 refs., 11 figs., 9 tabs.

  7. Air gasification of empty fruit bunch for hydrogen-rich gas production in a fluidized-bed reactor

    Energy Technology Data Exchange (ETDEWEB)

    Mohammed, M.A.A.; Salmiaton, A.; Wan Azlina, W.A.K.G.; Mohammad Amran, M.S.; Fakhru' l-Razi, A. [Department of Chemical and Environmental Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia)

    2011-02-15

    A study on gasification of empty fruit bunch (EFB), a waste of the palm oil industry, was investigated. The composition and particle size distribution of feedstock were determined and the thermal degradation behaviour was analysed by a thermogravimetric analysis (TGA). Then fluidized bed bench scale gasification unit was used to investigate the effect of the operating parameters on EFB air gasification namely reactor temperature in the range of 700-1000 C, feedstock particle size in the range of 0.3-1.0 mm and equivalence ratio (ER) in the range of 0.15-0.35. The main gas species generated, as identified by a gas chromatography (GC), were H{sub 2}, CO, CO{sub 2} and CH{sub 4}. With temperature increasing from 700 C to 1000 C, the total gas yield was enhanced greatly and reached the maximum value ({proportional_to}92 wt.%, on the raw biomass sample basis) at 1000 C with big portions of H{sub 2} (38.02 vol.%) and CO (36.36 vol.%). Feedstock particle size showed an influence on the upgrading of H{sub 2}, CO and CH{sub 4} yields. The feedstock particle size of 0.3-0.5 mm, was found to obtain a higher H{sub 2} yield (33.93 vol.%), and higher LHV of gas product (15.26 MJ/m{sup 3}). Equivalence ratio (ER) showed a significant influence on the upgrading of hydrogen production and product distribution. The optimum ER (0.25) was found to attain a higher H{sub 2} yield (27.31 vol.%) at 850 C. Due to the low efficiency of bench scale gasification unit the system needs to be scaling-up. The cost analysis for scale-up EFB gasification unit showed that the hydrogen supply cost is RM 6.70/kg EFB (2.11/kg = 0.18/Nm{sup 3}). (author)

  8. Air gasification of empty fruit bunch for hydrogen-rich gas production in a fluidized-bed reactor

    International Nuclear Information System (INIS)

    A study on gasification of empty fruit bunch (EFB), a waste of the palm oil industry, was investigated. The composition and particle size distribution of feedstock were determined and the thermal degradation behaviour was analysed by a thermogravimetric analysis (TGA). Then fluidized bed bench scale gasification unit was used to investigate the effect of the operating parameters on EFB air gasification namely reactor temperature in the range of 700-1000 oC, feedstock particle size in the range of 0.3-1.0 mm and equivalence ratio (ER) in the range of 0.15-0.35. The main gas species generated, as identified by a gas chromatography (GC), were H2, CO, CO2 and CH4. With temperature increasing from 700 oC to 1000 oC, the total gas yield was enhanced greatly and reached the maximum value (∼92 wt.%, on the raw biomass sample basis) at 1000 oC with big portions of H2 (38.02 vol.%) and CO (36.36 vol.%). Feedstock particle size showed an influence on the upgrading of H2, CO and CH4 yields. The feedstock particle size of 0.3-0.5 mm, was found to obtain a higher H2 yield (33.93 vol.%), and higher LHV of gas product (15.26 MJ/m3). Equivalence ratio (ER) showed a significant influence on the upgrading of hydrogen production and product distribution. The optimum ER (0.25) was found to attain a higher H2 yield (27.31 vol.%) at 850 oC. Due to the low efficiency of bench scale gasification unit the system needs to be scaling-up. The cost analysis for scale-up EFB gasification unit showed that the hydrogen supply cost is RM 6.70/kg EFB ($2.11/kg = $0.18/Nm3).

  9. Steam gasification of char from wood chips fast pyrolysis: Development of a semi-empirical model for a fluidized bed reactor application

    International Nuclear Information System (INIS)

    This study, performed in the context of GAYA project, focuses on the development of a simple predictive model about steam gasification of char from woodchips fast pyrolysis. A semi-empirical model was developed through experiments in a macro thermogravimetric analyzer which owns the peculiar ability of fast heating, as well as to deal with macro-size particles and higher mass loads compared to conventional TGA. The experimental results show that gasification is controlled by chemical kinetics and internal transfer phenomena. During gasification, char particles can be considered as isothermal in a given range of temperatures and particle sizes, more likely for low values. The gasification model was based on the effectiveness factor, which involves the chemical kinetics and diffusion rate. The chemical kinetics were expressed by a classical Arrhenius law, whereas empirical expressions from mathematical fitting of the experimental data were established for the diffusion coefficient and surface function. The diffusion coefficient from this work is suspected to probably include supplementary rate limiting phenomena, apart from steam porous diffusion, such as H2 inhibition and/or the decrease of temperature within char particles because of the endothermic character of gasification. The model globally predicts with accuracy the gasification rate in typical operating conditions of a fluidized bed reactor. For its simplicity and reliability, this approach can be used for the modelling of char gasification in the conditions of interest. - Highlights: • Char gasification is controlled by chemical kinetics and internal transfers. • Char particles are isothermal during gasification only at certain conditions. • The temperature decrease within char particles may affect gasification rate. • Gasification within the particle could be inhibited by the produced H2. • The developed semi-empirical model predicts with accuracy gasification rate

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

    Czech Academy of Sciences Publication Activity Database

    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

  11. Biomass gasification: the understanding of sulfur, tar, and char reaction in fluidized bed gasifiers

    OpenAIRE

    Meng, X.

    2012-01-01

    As one of the currently available thermo-chemical conversion technologies, biomass gasification has received considerable interest since it increases options for combining with various power generation systems. The product gas or syngas produced from biomass gasification is environmental friendly alternatives to conventional petrochemical fuels for the production of electricity, hydrogen, synthetic transportation biofuels and other chemicals. The product gas normally contains the major compon...

  12. Environmental assessment of the atlas bio-energy waste wood fluidized bed gasification power plant. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Holzman, M.I.

    1995-08-01

    The Atlas Bio-Energy Corporation is proposing to develop and operate a 3 MW power plant in Brooklyn, New York that will produce electricity by gasification of waste wood and combustion of the produced low-Btu gas in a conventional package steam boiler coupled to a steam-electric generator. The objectives of this project were to assist Atlas in addressing the environmental permit requirements for the proposed power plant and to evaluate the environmental and economic impacts of the project compared to more conventional small power plants. The project`s goal was to help promote the commercialization of biomass gasification as an environmentally acceptable and economically attractive alternative to conventional wood combustion. The specific components of this research included: (1) Development of a permitting strategy plan; (2) Characterization of New York City waste wood; (3) Characterization of fluidized bed gasifier/boiler emissions; (4) Performance of an environmental impact analysis; (5) Preparation of an economic evaluation; and (6) Discussion of operational and maintenance concerns. The project is being performed in two phases. Phase I, which is the subject of this report, involves the environmental permitting and environmental/economic assessment of the project. Pending NYSERDA participation, Phase II will include development and implementation of a demonstration program to evaluate the environmental and economic impacts of the full-scale gasification project.

  13. Comprehensive study of the influence of total pressure on products yields in fluidized bed gasification of wood sawdust

    Energy Technology Data Exchange (ETDEWEB)

    Valin, Sylvie; Ravel, Serge; Guillaudeau, Jacques; Thiery, Sebastien [CEA, DEN, DTN/SE2T/LTE, 17 rue des Martyrs, 38054 Grenoble cedex 9 (France)

    2010-10-15

    Wood sawdust gasification experiments were performed in a steam fluidized bed at 800 C between 2 and 10 bar. An evolution of gas yields with time was measured during the tests, and especially an increase of hydrogen and carbon dioxide yields. This test duration effect was ascribed to char build-up in the bed. As tests proceed, the contribution of char steam gasification to gas yield increases, and the catalytic effect of char on hydrocarbons and tar conversion and on water-gas shift reaction is enhanced. As total pressure increases from 2 to 10 bar, hydrogen, carbon dioxide and methane yields increase by 16%, 53% and 38% respectively, whereas carbon monoxide yield decreases by 33%. The changes in gaseous yields with pressure can be partly explained by the influence of pressure on gas phase reactions (acceleration of water-gas shift kinetics and change in hydrocarbon reactions). The increase of methane yield with pressure is rather suggested to be linked to a change in secondary pyrolysis reactions scheme under high pressure. (author)

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

    International Nuclear Information System (INIS)

    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

  15. Fundamental studies of synthesis-gas production based on fluidised-bed gasification of biomass - UCGFUNDA

    Energy Technology Data Exchange (ETDEWEB)

    Reinikainen, M. [VTT Technical Research Centre of Finland, Espoo (Finland)], email: matti.reinikainen@vtt.fi

    2012-07-01

    The project was directed towards improved methods of producing transportation bio-fuels via the synthesis-gas route. The aim of the project was to broaden and deepen the knowledge base and, in particular, generate new fundamental information about the most critical process steps from the point of view of the realisation of the technology. The subtopics of the research project were: (1) Fuel characterisation and ash behaviour in the gasification step (2) Reaction mechanisms related to gas cleaning, in particular the reactions of hydrocarbons at gasification temperatures, during hot-gas filtration and on catalytic surfaces (3) Evaluations of alternative process configurations and applications (4) Monitoring of developments elsewhere in the world (5) New analysis techniques (6) Hydrogen from biomass via gasification.

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

    Science.gov (United States)

    Hoersgen, B.; Koehne, H.

    1980-11-01

    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.

  17. Biomass gasification in fixed bed type down draft: theoretical and experimental aspects; Gasificacao de biomassa em leito fixo tipo concorrente: aspectos teoricos e experimentais

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Juan Daniel; Andrade, Rubenildo Vieira; Lora, Electo Eduardo Silva [Universidade Federal de Itajuba (UNIFEI), MG (Brazil). Inst. de Engenharia Mecanica. Nucleo de Excelencia em Geracao Termeletrica e Distribuida

    2008-07-01

    Actually are recognizing the advantages of biomass in reducing dependence on fossil fuels and significant reduction in emissions of greenhouse effect gases such as Co2. Also are known the different conversion of biomass routes for their use or exploitation, such as thermochemical process (gasification, pyrolysis and combustion), the biological process (fermentation and transesterification) and the physical process (densification, reducing grain and mechanical pressing). In this sense, the gasification is regarded as the most promising mechanism to obtain a homogeneous gaseous fuel with sufficient quality in the small scale distributed generation. This work presents some aspects of biomass gasification in fixed bed, as well as some preliminary results in the evaluation and operation of fixed bed down draft gasifier with double stage air supply of the NEST, identifying the adequate air supply quantity (equivalence ratio in the range of 0,35 to 0,45) for obtaining a fuel gas with lower heating value around 4 MJ/N m3. (author)

  18. Two stage fluid bed-plasma gasification process for solid waste valorisation: technical review and preliminary thermodynamic modelling of sulphur emissions.

    Science.gov (United States)

    Morrin, Shane; Lettieri, Paola; Chapman, Chris; Mazzei, Luca

    2012-04-01

    Gasification of solid waste for energy has significant potential given an abundant feed supply and strong policy drivers. Nonetheless, significant ambiguities in the knowledge base are apparent. Consequently this study investigates sulphur mechanisms within a novel two stage fluid bed-plasma gasification process. This paper includes a detailed review of gasification and plasma fundamentals in relation to the specific process, along with insight on MSW based feedstock properties and sulphur pollutant therein. As a first step to understanding sulphur partitioning and speciation within the process, thermodynamic modelling of the fluid bed stage has been performed. Preliminary findings, supported by plant experience, indicate the prominence of solid phase sulphur species (as opposed to H(2)S) - Na and K based species in particular. Work is underway to further investigate and validate this. PMID:21982278

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

    Directory of Open Access Journals (Sweden)

    Junaid Akhlas

    2015-10-01

    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.

  20. Plastic waste elimination by co-gasification with coal and biomass in fluidized bed with air in pilot plant

    Energy Technology Data Exchange (ETDEWEB)

    Aznar, Maria P.; Caballero, Miguel A.; Sancho, Jesus A.; Frances, E. [Chemical and Environmental Engineering Department, Centro Politecnico Superior, Maria de Luna 3, University of Zaragoza, 50018 Zaragoza (Spain)

    2006-05-15

    Treatment of plastic waste by gasification in fluidized bed with air using dolomite as tar cracking catalyst has been studied. The gasifier has a 1 m high bed zone (diameter of 9.2 cm) followed by a 1 m high freeboard (diameter of 15.4 cm). The feedstock is composed of blends of plastic waste with pine wood sawdust and coal at flow rates of 1-4 kg/h. Operating variables studied were gasifier bed temperature (750-880 {sup o}C), equivalence ratio (0.30-0.46), feedstock composition and the influence of secondary air insertion in freeboard. Product distribution includes gas and char yields, gas composition (H{sub 2}, CO, CO{sub 2}, CH{sub 4}, light hydrocarbons), heating value and tar content in the flue gas. As a result, a gas with a medium hydrogen content (up to 15% dry basis) and low tar content (less than 0.5 g/m{sub n}{sup 3}) is obtained. (author)

  1. Fundamental studies of synthesis-gas production based on fluidised-bed gasification of biomass - UCGFunda

    Energy Technology Data Exchange (ETDEWEB)

    Reinikainen, M.; Moilanen, A.; Simell, P.; Hannula, I.; Kurkela, E. (VTT Technical Research Centre of Finland, Espoo (Finland)), Email: matti.reinikainen@vtt.fi; Suominen, T.P. (Aabo Akademi, Turku (Finland). Lab. of Industrial Chemistry and Reaction Engineering); Linnekoski, J.; Roenkkoenen, E. (Aalto University, School of Science and Technology, Espoo (Finland). Lab. of Industrial Chemistry.)

    2010-10-15

    The research is directed towards methods of producing transportation bio-fuels via the synthesis-gas route, with emphasis on the synthesis-gas production and gas cleaning steps. The subtopics of the research project are (1) fuel characterisation and ash behaviour in the gasification step, (2) reaction mechanisms related to gas cleaning, (3) evaluations of alternative process configurations and applications and (4) international cooperation. VTT itself finances also two additional subtopics: (5) new analysis techniques and (6) hydrogen from biomass via gasification. The project comprises experimental work, modelling, techno-economic evaluations as well as studies based on literature. The project is steered by a wide industrial consortium and the research work is carried out by VTT, Aalto University and Aabo Akademi. International development in syngas technology has been closely monitored in all subtopics as well as by participating in relevant IEA-tasks. (orig.)

  2. Energy analysis of two stage packed-bed chemical looping combustion configurations for integrated gasification combined cycles

    International Nuclear Information System (INIS)

    Chemical looping combustion is a promising technology for power production with integrated CO2 capture. High overall efficiencies can be reached, if the CLC reactors are operated at elevated pressures and high temperature, which can be accommodated in packed bed reactors. More possible oxygen carriers can be selected if the desired temperature rise for power production is achieved in a two stage chemical looping combustion (TS-CLC) process. In this work, the TS-CLC configuration using copper and manganese based oxygen carriers has been integrated in a complete power plant based on coal gasification (IG-CLC). An extensive energy analysis based on the combined use of a packed bed reactor modeling tool and a complete process simulation has been undertaken. An economic estimation of the reactors capital cost has also been carried out. From the material and energy balances the IG-CLC with one stage nickel-based CLC process results in a net electric efficiency of 41.1% on low heating value basis. In case of TS-CLC, efficiencies of 40.3%–40.8% have been obtained. This demonstrated that IGCC (integrated gasification combined cycles) adopting a TS-CLC process can also achieve high efficiency compared to conventional CO2 capture technologies. Although a larger reactor volume is required for TS-CLC, the total estimated investment costs are a factor two lower, because the oxygen carriers are much cheaper. - Highlights: • Complete IG-CLC power plants have been evaluated for different CLC configurations. • Novel operation strategy for the TS-CLC has been proposed: TS-CLC parallel. • The estimated capital costs of TS-CLC are a factor two smaller than one stage CLC. • The process efficiency of TS-CLC is demonstrated to be close to the one stage CLC

  3. Simulation assessment of continuous simulating moving bed chromatography process with partial feed and new strategy with partial feed

    OpenAIRE

    Khan, H.

    2009-01-01

    Partial Feed simulating moving bed (SMB) has proved to be more efficient in binary separation performance (purity, recovery, productivity) because of its two additional degrees of freedom, namely feed length and feed time, as compared to classical SMB process. The binary separation of dextran T6 and fructose with linear isotherm is modeled with Aspen Chromatography simulator in a four zone SMB with one column per zone for both normal-feed and Partial Feed. Increase in number of feed length an...

  4. Catalytic steam gasification of biomass in fluidized bed at low temperature: Conversion from livestock manure compost to hydrogen-rich syngas

    International Nuclear Information System (INIS)

    Utilizing large amounts of animal waste as a source of renewable energy has the potential to reduce its disposal problems and associated pollution issues. Gasification characteristics of the manure compost make it possible for low temperature gasification. In this paper, an energy efficient approach to hydrogen-rich syngas from manure compost is represented at relatively low temperature, around 600 oC, in a continuous-feeding fluidized bed reactor. The effects of catalyst performance, reactor temperature, steam, and reaction type on gas yield, gas composition, and carbon conversion efficiency are discussed. The Ni-Al2O3 catalyst simultaneously promotes tar cracking and steam reforming. Higher temperature contributes to higher gas yield and carbon conversion. The steam introduction increases hydrogen yield, by steam reforming and water-gas shift reaction. Two-stage gasification is also tried, showing the advantage of better catalyst utilization and enhancing the catalytic reactions to some extent.

  5. Fundamental studies of synthesis-gas production based on fluidised-bed gasification of biomass (UCGFunda)

    Energy Technology Data Exchange (ETDEWEB)

    Reinikainen, M.; Moilanen, A.; Simell, P.; Hannula, I.; Nasrullah, M.; Kurkela, E. (VTT Technical Research Centre of Finland, Espoo (Finland))

    2009-10-15

    The research is directed towards methods of producing transportation bio-fuels via the synthesis-gas route, with emphasis on the synthesis-gas production and gas cleaning steps. The subtopics of the research project are (1) fuel characterisation and ash behaviour in the gasification step, (2) reaction mechanisms related to gas cleaning, (3) evaluations of alternative process configurations and applications and (4) international co-operation. VTT itself finances also two additional subtopics: (5) new analysis techniques and (6) hydrogen from biomass via gasification. A lot of data on the reactivity and ash sintering properties of various kinds of biomasses has been obtained in the project and the information will now be formulated into a mathematical model. In addition to catalysis also thermal reactions play an important role in gas cleaning. Both experimental and modelling work on both of the reaction types is being carried out. Three techno-economic evaluations on alternative and competing technologies will be completed in the coming year. International development in syngas technology has been closely monitored in all subtopics as well as by participating in relevant IEA-tasks. New analysis techniques developed in the project have proven very useful and for instance a fast on-line tar analysis method is now well established. (orig.)

  6. Preliminary results on the ash behavior of peach stones during fluidized bed gasification: evaluation of fractionation and leaching as pre-treatments

    Energy Technology Data Exchange (ETDEWEB)

    Arvelakis, S.; Koukios, E.G. [National Technical Univ., Athens (Greece). Dept. of Chemical Engineering; Gehrmann, H. [Clausthaler Umwelttechnik Institut GmbH, Claushal Zellerfeld (Germany); Beckmann, M. [Bauhaus Universitat Dept. of Process Engineering and Environment, Weimar (Germany)

    2005-03-01

    Peach stones comprise a valuable agroindustrial by-product that is available in many countries of the World and especially in the Mediterranean region. A number of important advantages such as its high energy value, the low ash content in combination with the absence of transportation costs due to the fact that is produced in agro-industries, make peach stones an ideal fuel for energy production via gasification. Gasification tests were performed in a lab-scale fluidized bed gasifier in order to study the behavior of peach stones and especially its ash during the gasification process. Apart from the tests with the initial peach stone samples, gasification tests were performed using peach stones that had been pre-treated using two different methods fractionation and leaching. Pre-treatments used in order to study their effect on the beneficiation of the materials ash and on the avoidance of ash-related problems such as deposition, agglomeration and corrosion during the gasification process. A water-cooled steel tube placed vertical to the flow of the gasification gases was used in order to collect samples of ash deposits that were analyzed using SEM-EDX analysis techniques in order to assess the effect of the pre-treatment techniques on the peach stones ash behavior. The produced results showed that peach stones can be used as gasification feedstock without significant ash problems. Fractionation resulted in a deterioration of the ash behavior of the material, increasing the amounts of alkali metals and chlorine included in its ash, while leaching showed a positive effect but to a moderate extent. (author)

  7. A comparison of circulating fluidised bed combustion and gasification power plant technologies for processing mixtures of coal, biomass and plastic waste

    Energy Technology Data Exchange (ETDEWEB)

    McIlveen-Wright, D.R.; Huang, Y.; McMullan, J.T. [NICERT, University of Ulster at Jordanstown, Newtownabbey BT37 0QB, Northern Ireland (United Kingdom); Pinto, F.; Franco, C.; Gulyurtlu, I. [INETI-DEECA, Estrada do Paco do Lumiar, 22, 1649-038 Lisboa (Portugal); Armesto, L.; Cabanillas, A. [CIEMAT, Avda Complutense, 22, 28040 Madrid (Spain); Caballero, M.A.; Aznar, M.P. [Chemical and Environmental Engineering Department, Centro Politecnico Superior, Maria de Luna, University of Saragossa, 50018 Saragossa (Spain)

    2006-09-15

    Environmental regulations concerning emission limitations from the use of fossil fuels in large combustion plants have stimulated interest in biomass for electricity generation. The main objective of the present study was to examine the technical and economic viability of using combustion and gasification of coal mixed with biomass and plastic wastes, with the aim of developing an environmentally acceptable process to decrease their amounts in the waste stream through energy recovery. Mixtures of a high ash coal with biomass and/or plastic using fluidised bed technologies (combustion and gasification) were considered. Experiments were carried out in laboratory and pilot plant fluidised bed systems on the combustion and air/catalyst and air/steam gasification of these feedstocks and the data obtained were used in the techno-economic analyses. The experimental results were used in simulations of medium to large-scale circulating fluidised bed (CFB) power generation plants. Techno-economic analysis of the modelled CFB combustion systems showed efficiencies of around 40.5% (and around 46.5% for the modelled CFB gasification systems) when fuelled solely by coal, which were only minimally affected by co-firing with up to 20% biomass and/or wastes. Specific investments were found to be around $2150/kWe to $2400/kWe ($1350/kWe to $1450/kWe) and break-even electricity selling prices to be around $68/MWh to $78/MWh ($49/MWh to $54/MWh). Their emissions were found to be within the emission limit values of the large combustion plant directive. Fluidised bed technologies were found to be very suitable for co-firing coal and biomass and/or plastic waste and to offer good options for the replacement of obsolete or polluting power plants. (author)

  8. A comparison of circulating fluidised bed combustion and gasification power plant technologies for processing mixtures of coal, biomass and plastic waste

    International Nuclear Information System (INIS)

    Environmental regulations concerning emission limitations from the use of fossil fuels in large combustion plants have stimulated interest in biomass for electricity generation. The main objective of the present study was to examine the technical and economic viability of using combustion and gasification of coal mixed with biomass and plastic wastes, with the aim of developing an environmentally acceptable process to decrease their amounts in the waste stream through energy recovery. Mixtures of a high ash coal with biomass and/or plastic using fluidised bed technologies (combustion and gasification) were considered. Experiments were carried out in laboratory and pilot plant fluidised bed systems on the combustion and air/catalyst and air/steam gasification of these feedstocks and the data obtained were used in the techno-economic analyses. The experimental results were used in simulations of medium to large-scale circulating fluidised bed (CFB) power generation plants. Techno-economic analysis of the modelled CFB combustion systems showed efficiencies of around 40.5% (and around 46.5% for the modelled CFB gasification systems) when fuelled solely by coal, which were only minimally affected by co-firing with up to 20% biomass and/or wastes. Specific investments were found to be around $2150/kWe to $2400/kWe ($1350/kWe to $1450/kWe) and break-even electricity selling prices to be around $68/MWh to $78/MWh ($49/MWh to $54/MWh). Their emissions were found to be within the emission limit values of the large combustion plant directive. Fluidised bed technologies were found to be very suitable for co-firing coal and biomass and/or plastic waste and to offer good options for the replacement of obsolete or polluting power plants. (author)

  9. Performance Analysis of Rdf Gasification in a Two Stage Fluid Bed - Plasma Process

    OpenAIRE

    Materazzi, M.; Lettieri, P.; Taylor, R.; Chapman, C

    2015-01-01

    The major technical problems faced by stand-alone fluidized bed gasifiers (FBG) for waste-to gas applications are intrinsically related to the composition and physical properties of waste materials, such as RDF. The high quantity of ash and volatile material in RDF can provide a decrease in thermal output, create high ash clinkering, and increase emission of tars and CO2, thus affecting the operability for clean syngas generation at industrial scale. By contrast, a two-stage process which sep...

  10. Potentials of Selected Malaysian Biomasses as Co-Gasification Fuels with Oil Palm Fronds in a Fixed-Bed Downdraft Gasifier

    Directory of Open Access Journals (Sweden)

    Moni Mohamad Nazmi Zaidi

    2014-07-01

    Full Text Available Oil palm frond (OPF has been successfully gasified to produce syngas and has since deemed as a potential source of biomass fuel in Malaysia. However, if OPF is to be utilized as a main fuel for industrial-scale firing/gasification plant, interruption in fuel supply may occur due to numerous reasons, for instance inefficient fuel processing and ineffective transportation. A secondary supporting solid fuel is therefore necessary as a partial component to the main fuel in such cases, where the secondary fuel is combusted with the main fuel to adhere to main fuel shortage. Gasification of two fuels together, known as co-gasification, is practiced worldwide, some in industrial scale. However, current practice utilizes biomass fuel as the secondary fuel to coal in co-gasification. This investigation explores into the feasibility of co-gasifying two biomass fuels together to produce syngas. OPF was chosen as the primary fuel and a selection of Malaysian biomasses were studied to discover their compatibility with OPF in co-gasification. Biomass selection was made using score-and-rank method and their selection criteria are concisely discussed.

  11. About the gasification of untreated scrap and waste wood in fluidized bed reactor for use in decentralized gas engine-cogeneration plants; Zur Vergasung von Rest- und Abfallholz in Wirbelschichtreaktoren fuer dezentrale Energieversorgungsanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Tepper, H.

    2005-10-20

    This dissertation examines the thermochemical conversion (gasification) of untreated scrap and waste wood in combustible gases for use in decentralized gas engine-cogeneration plants of low output (1 to 10 MW fuel power). A general section goes into the basics of the energetic utilization of solid biomass, the subprocesses of thermochemical conversion being described in more detail. Special attention is given to the processes and state of the art of biomass gasification in decentralized plants. A theoretical section analyzes the gasification models for solid biomass presented in the literature. Based on this analysis, a simplified kinetic model is derived for the gasification of untreated scrap and waste wood with air in bubbling fluidized bed reactors. It includes a fluid mechanic analysis of the fluidized bed based on HILLIGARDT, an empirical pyrolysis model and a global kinetic approach to the main chemical reaction taken from the literature. An experimental section describes the tests of the gasification of forest scrap wood in a semi-industrial fluidized bed gasification test plant with 150 kW fuel power and presents the significant test results. The gasification model derived is applied to check the test plant's standard settings and compare them with measured values. Furthermore, the model is employed to explain basic reaction paths and zones and to perform concluding parameter simulations. (orig.)

  12. Sulphur distribution during air gasification of kraft black liquor solids in a fluidized bed of TiO{sub 2} particles

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, L. [BC Research Inc., Vancouver, BC (Canada); Van Heiningen, A.R.P. [Main Univ., Orono, ME (United States)

    1999-06-01

    A study was conducted to determine if kraft black liquor (KBL) gasification is a viable alternative for conventional kraft recovery, and to evaluate the sulphur distribution during gasification of KBL in the presence of TiO{sub 2}. KBL gasification can be combined with direct causticization by TiO{sub 2} to prevent smelt formation, minimize sodium emission and to eliminate the lime causticizing cycle. However, the presence of TiO{sub 2} should theoretically lead to the complete volatilization of the sulphur in KBL mostly as H{sub 2}S and Na{sub 2}S. Experiments were conducted at 700 to 900 degrees C in a pilot fluidized bed system. The bed residual solids were analyzed for sulphite, sulphate, thiosulphate and sulphide using various techniques. Results showed that Na{sub 2}S was not found in the KBL solids but Na{sub 2}S{sub 2}O{sub 3} content was high probably because of oxidation of NA{sub 2}S during drying. It was suggested that thermal cracking of CH{sub 3}SH and (CH{sub 3}) {sub 2}S is the major cause for H{sub 2}S generation. 18 refs., 3 tabs., 6 figs.

  13. Gasification of rice straw in a fluidized-bed gasifier for syngas application in close-coupled boiler-gasifier systems.

    Science.gov (United States)

    Calvo, L F; Gil, M V; Otero, M; Morán, A; García, A I

    2012-04-01

    The feasibility and operation performance of the gasification of rice straw in an atmospheric fluidized-bed gasifier was studied. The gasification was carried out between 700 and 850 °C. The stoichiometric air-fuel ratio (A/F) for rice straw was 4.28 and air supplied was 7-25% of that necessary for stoichiometric combustion. Mass and power balances, tar concentration, produced gas composition, gas phase ammonia, chloride and potassium concentrations, agglomeration tendencies and gas efficiencies were assessed. Agglomeration was avoided by replacing the normal alumina-silicate bed by a mixture of alumina-silicate sand and MgO. It was shown that it is possible to produce high quality syngas from the gasification of rice straw. Under the experimental conditions used, the higher heating value (HHV) of the produced gas reached 5.1 MJ Nm(-3), the hot gas efficiency 61% and the cold gas efficiency 52%. The obtained results prove that rice straw may be used as fuel for close-coupled boiler-gasifier systems. PMID:22297044

  14. Pilot Scale Test to Treat High Concentration Gasification Wastewater Using Catalytic Oxidation and Aerobic Biological Fluid-Bed Combination Process

    Institute of Scientific and Technical Information of China (English)

    LI Na; HUANG Jun-li; WANG Wei; ZHAO Jian-wei; WANG Cui-lin; CUI Chong-wei

    2008-01-01

    The gasitication wastewatet is a kind of typical ocgauic industrial wastewatet with high chemical oxygen demand (COD) and ammonia uitrogen,which could not be completely degraded by the traditional physical,chimical and bidogical method.So it is very important to find an effective treatment process.A combination process of catalytic oxidation with noble metal catalysts and aerobic biological fluid-bed packed with the new uitrastructure biological carriers,which was devdoped by ourselves,was investigated to treat the gasification wastcwater.The pilot scale test with 0.5m3/h influent flow was carried out to investigate the performance of this new combination process.The results showed that the effluent COD was 84.02 mg/L,ananonia nitrogen was 14.15 mg/L,and total phenol was 0.20 mg/L,which could completely meet the Grade I of Wastewater Discharge Standard (GB8978-1996),when the influent average COD was 5564 mg/L,anunonia nitrogen was 237 mg/L,and total phenol was 1100 mg/L.The two catalytic reactors could evidently improve the wastewater biodegradability,and the value of BOD5/COD(B/C) increased from 0.23 to 0.413 in the one-stage catalytic reactor and from 0.273 to 0.421 in two-stage catalytic reactor.The further experiment results showed that the effluent quality of this new combination progess could still meet the discharge standard,aromatic and heterocyclic compounds were degraded effectively in this combination process.

  15. Simulation assessment of continuous simulating moving bed chromatography process with partial feed and new strategy with partial feed

    Directory of Open Access Journals (Sweden)

    H. Khan

    2009-09-01

    Full Text Available Partial Feed simulating moving bed (SMB has proved to be more efficient in binary separation performance (purity, recovery, productivity because of its two additional degrees of freedom, namely feed length and feed time, as compared to classical SMB process. The binary separation of dextran T6 and fructose with linear isotherm is modeled with Aspen Chromatography simulator in a four zone SMB with one column per zone for both normal-feed and Partial Feed. Increase in number of feed length and feed time in the cycle plays a very important role in the separation performance with Partial Feed. In addition, the effect of mode of operation (early or late introduction of increase in number of feed length in the cycle on product purity and recovery is also investigated. Furthermore, the binary separation system is designed with the safety margin method and the optimum operating parameters for simulation are calculated with triangle theory. Finally, a new strategy with Partial Feed is developed, showing improved separation performance relative to the basic four-zone SMB with regard to extract stream purity and recovery. The results of the proposed study can served as a useful summary of Partial Feed operation.

  16. Sewage sludge gasification in fluidized bed: influence of temperature and the stoichiometric relation; Gasificacion de fangos de depuradora en lecho fluidizado: influencia de la temperatura y de la relacion estequiometrica

    Energy Technology Data Exchange (ETDEWEB)

    Manya, J.J.; Gonzalo, A.; Sanchez, J.L.; Arauzo, J. [Universidad de Zaragoza, Aragon (Spain). Inst. de Investigacion en Ingenieria. Grupo de Procesos Termoquimicos; Rocha, J.D. [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Nucleo Interdisciplinar de Planejamento Energetico (NIPE); Mesa Perez, J.M. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Fac. de Engenharia Agricola (FEAGRI)

    2004-07-01

    The gasification of a dry granular sewage sludge has been experimentally studied. The gasification was carried out in a bench scale BFB facility, operated at steady state. The attention was focused on the presence of tar in the produced gas which affect the process efficiency and give negative drawbacks in the utilization in motors. The influence of two operating variables (bed temperature and equivalence ratio) on the gasification performances has been explored. Results show that the composition of produced gas is quite dependent of the variables analyzed. However, the results of tar yield show an unexpected behaviour. (author)

  17. Concentration of HCl, HF and Sulfur Compounds in Fuel Gas from Fluidized Bed Gasification of Coals and Wood by Steam-Oxygen Mixtures

    Czech Academy of Sciences Publication Activity Database

    Svoboda, Karel; Pohořelý, Michael; Jeremiáš, Michal; Kameníková, Petra; Skoblia, S.; Beňo, Z.; Šyc, Michal

    Praha : Orgit, 2012, P3.199. ISBN 978-80-905035-1-9. [International Congress of Chemical and Process Engineering CHISA 2012 and 15th Conference PRES 2012 /20./. Prague (CZ), 25.08.2012-29.08.2012] R&D Projects: GA TA ČR TA01020366 Grant ostatní: RFCS(XE) RFCR-CT-2010-00009, Institutional support: RVO:67985858 Keywords : fluidized bed * gasification * coal Subject RIV: CI - Industrial Chemistry, Chemical Engineering www.chisa.cz/2012

  18. Gasification of a Coal, Biomass, and a Coal-Biomass Mixture in a Fluidized Bed of Dolomite Particles by a Gas Containing Oxygen-CO2 Mixtures

    Czech Academy of Sciences Publication Activity Database

    Svoboda, Karel; Pohořelý, Michael; Kameníková, Petra; Jeremiáš, Michal; Skoblia, S.; Šyc, Michal; Punčochář, Miroslav

    Gliwice : Institute of Thermal Technology, 2011 - (Ksiadz, A.; Werle, S.), s. 114-115 ISBN 978-83-61506-06-5. [International Conference on Carbon Reduction Technologies CaReTECH 2011. Polish Jurassic Highland (Orle Gniazdo) (PL), 19.09.2011-22.09.2011] R&D Projects: GA MŠk 2B08048 Grant ostatní: RFCS(XE) CT-2010-00009 Institutional research plan: CEZ:AV0Z40720504 Keywords : fluidized bed * gasification * CO2 Subject RIV: JE - Non-nuclear Energetics, Energy Consumption ; Use

  19. Energy recovery by gasification of agricultural and forestry wastes in fluidized bed reactors and in moving bed reactors with internal recycle of pyrolysis gas; process development and reactor modelling. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Aarsen, F.G. van den; Susanto, H.; Beenackers, A.A.C.M.; Swaaij, W.P.M. van

    1986-01-01

    A modified co-current moving gasifier bed has been developed which substantially reduces product gas tar content compared to conventional down draft gasifiers and allows for a better scale-up of the reactor. These improvements have been realized by installing an ejector in the air inlet which sucks the pyrolysis gases into the gasifying air stream and allows for subsequent combustion of the pyrolysis products in a separate combustor. In relation to the modelling of a fluidized bed biomass gasifier, we studied the fast pyrolysis of beech wood particles and the char-carbondioxide gasification kinetics in a bench scale fluidized bed reactor. A 30 cm diameter fluidized bed biomass gasifier has been constructed and the reactor performance on wood and rice husks has been studied. Those experiments (at 50 kg biomass/hr) revealed that a good gas quality is produced if the reactor is operated above 800/sup 0/ C, in the co-current mode (bottomfeed). Ongoing research is on mass transfer and flow behaviour in the fluidized bed reactor; a mathematical model of the fluidized bed gasifier is under development.

  20. Cold test with a benchtop set-up for fluidized bed reactor using quartz sand to simulate gasification of coal cokes by concentrated solar radiation

    Science.gov (United States)

    Gokon, Nobuyuki; Tanabe, Tomoaki; Shimizu, Tadaaki; Kodama, Tatsuya

    2016-05-01

    The impacts of internal circulation of a mixture of coal-coke particles and quartz sand on the fluidization state in a fluidized bed reactor are investigated by a cold test with a benchtop set-up in order to design 10-30 kWth scale prototype windowed fluidized-bed reactor. Firstly, a basic relationship between pressure loss of inlet gas and gas velocity was experimentally examined using quartz sand with different particle sizes by a small-scale quartz tube with a distributor at ambient pressure and temperature. Based on the results, an appropriate particle range of quartz sand and layer height/layer diameter ratio (L/D ratio) was determined for a design of the fluidized bed reactor. Secondly, a windowed reactor mock-up was designed and fabricated for solar coke gasification using quartz sand as a bed material. The pressure loss between the inlet and outlet gases was examined, and descending cokes and sand particles on the sidewall of the reactor was observed in the reactor mock-up. The moving velocity and distance of descending particles/sands from the top to bottom of fluidized bed were measured by the visual observation of the colored tracer particles on outside wall of the reactor.

  1. Steam gasification of almond shells in a fluidised bed reactor: the influence of temperature and particle size on product yield and distribution

    Energy Technology Data Exchange (ETDEWEB)

    Rapagna, Sergio; Latif, Ajmal [Universita di L`Aquila (Italy). Dip. di Chimica, Ingegneria Chimica e Materiali

    1997-09-01

    The steam gasification of ground almond shells has been carried out in a continuous, bench scale, fluidised bed reactor in order to evaluate the effects of particle size and operating temperature on the product yield and distribution. The mean particle size was varied from nearly 300{mu}m to over 1 mm and the bed temperature from 600 to 800{sup o}C. The results reveal that for smaller particle sizes differences in product yield and distribution practically disappear as the higher temperature bound is approached, whereas for particles above 1 mm in diameter the yield continues to increase over the entire temperature range, never reaching that attained by the smaller particle systems. This behaviour is indicative of the increasing significance of extra-and/or intra-particle heat transfer limitations with increasing particle size. (author)

  2. An experimental study on hydrogen-rich gas production via steam gasification of biomass in a research-scale fluidized bed

    International Nuclear Information System (INIS)

    Highlights: • Steam gasification via fluidized-bed is an interesting technology for hydrogen rich gas production. • The increase of steam/biomass ratio plays a major role on the hydrogen yield. • Hydrogen yield slightly increases as the biomass particle size decreases. • Tar yield strongly depends on reaction temperature. - Abstract: A research scale fluidized-bed reactor has been built and used to study the effect of steam/biomass ratio, time duration of experiments, reactor temperature, and biomass particle size on hydrogen yield and tar content in produced syngas during steam gasification of biomass. Batch experiments were performed with wood residue crushed into three different sizes of 0.5–1 mm (small), 1–2.5 mm (medium), and 2.5–5 mm (large), at reactor temperatures of 700, 800, and 900 °C. As the steam/biomass ratio increases, a decrease in formation of CO, accompanied by an increase in the hydrogen concentration, is observed. As expected, an increase in reactor temperature leads to a significant increase of H2 output and tar reforming. The obtained results show that hydrogen yield increases as time duration of the experiment is increased. It is also found that a reduction in particle diameter leads to a significant improvement in hydrogen yield

  3. Co-gasification of biosolids with biomass: Thermogravimetric analysis and pilot scale study in a bubbling fluidized bed reactor.

    Science.gov (United States)

    Yu, Ming Ming; Masnadi, Mohammad S; Grace, John R; Bi, Xiaotao T; Lim, C Jim; Li, Yonghua

    2014-10-17

    This work studied the feasibility of co-gasification of biosolids with biomass as a means of disposal with energy recovery. The kinetics study at 800°C showed that biomass, such as switchgrass, could catalyze the reactions because switchgrass ash contained a high proportion of potassium, an excellent catalyst for gasification. However, biosolids could also inhibit gasification due to interaction between biomass alkali/alkaline earth metals and biosolids clay minerals. In the pilot scale experiments, increasing the proportion of biosolids in the feedstock affected gasification performance negatively. Syngas yield and char conversion decreased from 1.38 to 0.47m(3)/kg and 82-36% respectively as the biosolids proportion in the fuel increased from 0% to 100%. Over the same range, the tar content increased from 10.3 to 200g/m(3), while the ammonia concentration increased from 1660 to 19,200ppmv. No more than 25% biosolids in the fuel feed is recommended to maintain a reasonable gasification. PMID:25459803

  4. Stream and bed temperature response to partial-retention forest harvesting in a coastal headwater catchment

    Science.gov (United States)

    Moore, R. D.; Guenther, S.; Gomi, T.

    2012-12-01

    This study quantified the effects of partial-retention forest harvesting on stream and bed temperatures in a headwater catchment in coastal British Columbia, Canada. Stream temperature was recorded between 2002 and 2005 at four sites, three located within the harvested area and one upstream. Logging occurred in autumn 2004. Shallow groundwater temperatures, along with bed temperature profiles at depths of 1 to 30 cm, were recorded at 10-minute intervals in two hydrologically distinct reaches beginning in 2003 or 2004, depending on the site. The lower reach had smaller discharge contributions via lateral inflow from the hillslopes and fewer areas with upwelling and/or neutral flow across the stream bed compared to the middle reach. Based on a paired-catchment analysis, the logging treatment resulted in higher daily maximum stream and bed temperatures but smaller changes in daily minima. Changes in daily maximum stream temperature, averaged over July and August of the post-harvest year, ranged from 1.6 to 3 oC at different locations within the cut block. Post-harvest changes in bed temperature in the lower reach were lower than the changes in stream temperature, greater at sites with downwelling flow, and decreased with depth at both upwelling and downwelling sites, dropping to about 1 oC at a depth of 30 cm. In the middle reach, changes in daily maximum bed temperature, averaged over July and August, were generally about 1 oC and did not vary significantly with depth. The pre-harvest regression models for shallow groundwater were not suitable for applying the paired-catchment analysis to estimate the effects of harvesting.

  5. 鼓泡流化床垃圾衍生燃料富氧气化%Enriched-air gasification of refuse derived fuel in bubbling fluidized bed

    Institute of Scientific and Technical Information of China (English)

    牛淼淼; 黄亚继; 金保昇; 王妍艳; 董新新

    2014-01-01

    Enriched air gasification of two different refuse derived fuels (RDF) was performed in a bubbling fluidized bed reactor. Thermo-gravimetric analysis of the two RDFs was performed and the effect of temperature, equivalence ratio (ER) and oxygen percentage of enriched air was investigated. Both RDFs were composed of cellulose and plastics based materials. With increasing temperature from 650℃ to 800℃, concentrations of H2, CO and CH4 increased in both RDFs gasification. Gas yield and gasification efficiency were also improved. The combustible components first increased slightly and then decreased with increasing ER, while gas yield kept constant growth. The optimum ER values for RDF1 and RDF2 were 0.22 and 0.27 respectively for obtaining the highest gasification efficiency. The use of enriched air could improve gasification effectively and lead to higher heating value of the syngas. When oxygen percentage of enriched air was 45%, the maximum low heating values of the syngas for RDF1 and RDF2 were 8.6 MJ·m−3and 9.2 MJ·m−3respectively.%在鼓泡流化床上进行两种垃圾衍生燃料(RDF)的富氧气化试验,考察了RDF的热重特性并分析了气化温度、当量比及富氧浓度对气化特性的影响。结果表明:两种RDF均由纤维素及塑料类组分构成。随着温度由650℃升高至800℃,两种RDF产气的H2、CO及CH4浓度均逐渐增加,产气热值和气化效率同时提高。当量比增大时可燃组分浓度先略有增大后逐渐减小,但气体产率不断增大。RDF1及RDF2分别在当量比为0.22及0.27处达到最佳气化效率。富氧气化可有效改善气化品质,提升合成气热值,富氧浓度为45%时RDF1及RDF2合成气热值均达到最大,分别为8.6 MJ·m−3及9.2 MJ·m−3。

  6. Fluidized Bed Gasification as a Mature And Reliable Technology for the Production of Bio-Syngas and Applied in the Production of Liquid Transportation Fuels—A Review

    Directory of Open Access Journals (Sweden)

    Adrian H.M. Verkooijen

    2011-03-01

    Full Text Available Biomass is one of the renewable and potentially sustainable energy sources and has many possible applications varying from heat generation to the production of advanced secondary energy carriers. The latter option would allow mobile services like the transportation sector to reduce its dependency on the fossil fuel supply. This article reviews the state-of-the-art of the fluidization technology applied for the gasification of biomass aimed at the production of gas for subsequent synthesis of the liquid energy carriers via, e.g., the Fischer-Tropsch process. It discusses the advantages of the gasification technology over combustion, considers the size of the conversion plant in view of the local biomass availability, assesses the pros and cons of different gasifier types in view of the application of the product gas. Subsequently the article focuses on the fluidized bed technology to discuss the main process parameters and their influence on the product composition and the operability of the gasifier. Finally a synthesis process (FT is introduced shortly to illustrate the necessary gas cleaning steps in view of the purity requirements for the FT feed gas.

  7. Fluidized-bed gasification of biomass: Conversion of fine carabon particles in the freeboard; Biomassevergasung in der Wirbelschicht: Umsatz von feinen Kohlenstoffpartikeln im Freeboard

    Energy Technology Data Exchange (ETDEWEB)

    Miccio, F. [Ist. Ricerche sulla Combustione-CNR, Napoli (Italy); Moersch, O.; Spliethoff, H.; Hein, K.R.G. [Stuttgart Univ. (Germany). Inst. fuer Verfahrenstechnik und Dampfkesselwesen

    1998-09-01

    The conversion of carbon particles in gasification processes was investigated in a fluidized-bed reactor of the Institute of Chemical Engineering and Steam Boiler Technology of Stuttgart University. This reactor is heated electrically to process temperature, and freeboard coal particles can be sampled using an isokinetic probe. The fuel used in the experiments consisted of beech wood chips. The temperature and air rating, i.e. the main parameters of the process, were varied in order to investigate their influence on product gas quality and carbon conversion. The conversion rate is influenced to a significant extent by grain disintegration and discharge of carbon particles. In gasification conditions, a further conversion process takes place in the freeboard. (orig.) [Deutsch] In dieser Arbeit wird die Umsetzung von Kohlenstoffpartikeln unter Vergasungsbedingungen untersucht. Die Versuche wurden an einem Wirbelschichtreaktor des Instituts fuer Verfahrenstechnik und Dampfkesselwesen der Universitaet Stuttgart durchgefuehrt. Dieser Reaktor wird elektrisch auf Prozesstemperatur beheizt. Mit Hilfe einer isokinetischen Sonde koennen Proben von Kohlenstoffpartikeln im Freeboard genommen werden. Als Brennstoff wurden zerkleinerte Buchenholz-Hackschnitzel eingesetzt. Variiert wurden als Hauptparameter des Prozesses Temperatur und Luftzahl. Untersucht wurde der Einfluss dieser Parameter auf die Qualitaet des Produktgases und die Umsetzung des Kohlenstoffes. Kornzersetzungs- und Austragsvorgaenge von Kohlenstoffpartikeln spielen eine wichtige Rolle fuer den Kohlenstoffumsatz. Unter Vergasungsbedingungen findet im Freeboard eine weitere Umsetzung der Partikel statt. (orig.)

  8. Fluidized Bed Gasification of Coal-Oil and Coal-Water-Oil Slurries by Oxygen –Steam and Oxygen-CO2 Mixtures

    Czech Academy of Sciences Publication Activity Database

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

    2012-01-01

    Roč. 95, č. 1 (2012), s. 16-26. ISSN 0378-3820 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 slurries Subject RIV: JE - Non-nuclear Energetics, Energy Consumption ; Use Impact factor: 2.816, year: 2012 http://www.scopus.com/record/display.url?eid=2-s2.0-82455175439&origin=resultslist&sort=plf-f&src=s&st1=svoboda%2ck&sid=ikNGw6d45E-yyuMoDwlGiWn%3a420&sot=b&sdt=b&sl=22&s=AUTHOR-NAME%28svoboda%2ck%29&relpos=1&relpos=1&searchTerm=AUTHOR-NAME(svoboda,k)

  9. 浅析流化床生物质与煤共气化技术方案%Briefly Analyzing Scheme for Biomass and Coal Co-gasification Technology of Fluidized Bed

    Institute of Scientific and Technical Information of China (English)

    毕可军; 毛少祥; 孔北方; 柏林红

    2012-01-01

    In allusion to problems that the biomass was difficult to gasity independently, author has discussed the co-complemented technical scheme of biomass with coal co-gasification; has introduced the physical property of biomass and its gasification features; has discussed the technical features and process flow for pulverized coal gasification technology with fluidized bed of ash meh collection ; has presented the technical scheme to make co-gasification of biomass with coal on basis of pulverized coal gasification technology with fluidized bed of ash meh collection ; and also has presented the relative solution measures for existing problems.%针对生物质能源难以单独气化的问题,探讨了生物质与煤共气化的互补性技术方案;介绍了生物质的物理性质和气化特性;论述了灰融聚流化床粉煤气化技术的特点和工艺流程;提出了在灰融聚流化床粉煤气化的基础上进行生物质与煤共气化技术方案,对存在的问题提出了相关解决措施。

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

    International Nuclear Information System (INIS)

    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

  11. Coal Partial Gasification-Based Polygeneration System of Hydrogen and Electricity With CO_2 Capture%捕获CO_2的部分煤气化氢电联产系统

    Institute of Scientific and Technical Information of China (English)

    臧桂研; 徐玉杰; 张华良; 陈海生; 谭春青

    2012-01-01

    A novel coal partial gasification-based polygeneration system of hydrogen and electricity with CO_2 capture is proposed through the integration of cascade conversion of coal,reasonable utilization according to component and CO_2 capture.The system realizes partial gasification of coal by the use of a pressurized fluidized bed to decrease gasification difficulty and cost of the gasifier,so it holds the better economic performance.And at the same time,the thermodynamic characteristics and environmental performance are revealed roundly.Results show that carbon conversion ratio of the gasifier is a dominant factor to affect performance of the system,and that the system has excellent thermodynamic and environmental performance.The exergy efficiency of the system can reach 54.3% when CO_2 separation ratio is 59.7%.The study provides optional pathway for clean and effective utilization of coal.%基于煤炭分级转化、成分对口应用、污染物控制一体化等系统集成思路,提出了一种捕获CO_2的部分煤气化氢电联产系统。该系统利用增压流化床完成煤炭部分气化,降低了气化难度与气化炉造价,具有较好经济性;全面揭示了系统的热力和环境特性规律,指出气化炉碳转化率是影响系统热力性能的主要因素;系统具有良好的热力特性与环境特性,当CO_2的分离率为59.7%时,系统(火用)效率为54.3%。本文的研究为煤炭的清洁高效利用提供了可选择的途径。

  12. Poly-generation process for gasification of dairy manure with fixed beds%牛粪固定床气化多联产工艺

    Institute of Scientific and Technical Information of China (English)

    秦恒飞; 周建斌; 王筠祥; 张齐生

    2011-01-01

    In order to reduce greenhouse effect and environmental pollution caused by natural fermentation of cow dung and also to reduce the cost and increase benefits of the dairy farming, the dairy manure was gasified using homemade fixed bed SGL gasifier. The dairy manure gasification can get three products, such as flammable gas, dairy manure carbon and pyrolysis extract liquid. These three products were recycled to achieve the goals of emission reduction and pollution control. The influences of water content, gasification temperature and equivalence ratio were studied, and the results showed that the optimal gasification parameters were raw material 12%~18%, gasification temperature 850~ 900°C and equivalence ratio 0.25~0.30. When dairy manure moisture was 17.78%, gasification temperature was 850°C and equivalence ratio was 0.30, the yield of gas was 1.42 m3/kg' the inferior calorific value was 2.84 MJ/m3, the yield of dairy manure carbon was 23.82% and the yield of pyrolysis extract liquid was 24.17%. Dairy manure gasification of poly-generation process experiment can provide a theoretical basis for engineering implementation.%为了减少畜禽粪便自然发酵造成的温室效应和环境污染,降低养殖奶牛的成本和增加养殖奶牛的效益,该文利用自制的固、气、液(Solid,gas,liquid)多联产固定床气化炉将牛粪气化,气化可得到固体牛粪炭、可燃气、提取液三相产品,三相产品均可以资源化利用,从而达到减排、减污的目标.考察了含水率、气化温度及气化剂的当量比对气化效果的影响.结果表明:原料含水率控制在12%~18%,气化温度为850~900℃,当量比在0.25~0.30时,气化效果较好,牛粪含水率为17.78%,气化温度为850℃,当量比为0.30时,气体产率为1.42 m3·kg-1,可燃气体的低位热值为2.84MJm-3,牛粪炭得率为23.82%,提取液得率是24.17%.牛粪气化多联产工艺试验为工程化实施提了基础和基本数据.

  13. Gasification Product Improvement Facility (GPIF). Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    The gasifier selected for development under this contract is an innovative and patented hybrid technology which combines the best features of both fixed-bed and fluidized-bed types. PyGas{trademark}, meaning Pyrolysis Gasification, is well suited for integration into advanced power cycles such as IGCC. It is also well matched to hot gas clean-up technologies currently in development. Unlike other gasification technologies, PyGas can be designed into both large and small scale systems. It is expected that partial repowering with PyGas could be done at a cost of electricity of only 2.78 cents/kWh, more economical than natural gas repowering. It is extremely unfortunate that Government funding for such a noble cause is becoming reduced to the point where current contracts must be canceled. The Gasification Product Improvement Facility (GPIF) project was initiated to provide a test facility to support early commercialization of advanced fixed-bed coal gasification technology at a cost approaching $1,000 per kilowatt for electric power generation applications. The project was to include an innovative, advanced, air-blown, pressurized, fixed-bed, dry-bottom gasifier and a follow-on hot metal oxide gas desulfurization sub-system. To help defray the cost of testing materials, the facility was to be located at a nearby utility coal fired generating site. The patented PyGas{trademark} technology was selected via a competitive bidding process as the candidate which best fit overall DOE objectives. The paper describes the accomplishments to date.

  14. Gasification of oak sawdust, mesquite, corn stover, and cotton gin trash in a countercurrent fluidized bed pilot reactor

    Energy Technology Data Exchange (ETDEWEB)

    Beck, S.R.; Wang, M.J.; Hightower, J.A.

    1981-01-01

    The Synthesis Gas From Manure (SGFM) process was designed to convert cattle feedlot manure to ammonia synthesis gas. Current work is aimed at using any biomass feedstock to produce either medium-Btu gas or chemical feedstocks. This paper presents a comparison of the experimental results compiled on gasification of oak sawdust, corn stover, mesquite, and cotton gin trash in the SGFM pilot plant. A weighted comparison of the product gas, hydrocarbon, and hydrogen yields, gas quality, calorific value of product gas, percentage conversion of raw feed heating value to gas heating value, and operability of each feed indicated the oak sawdust was the best feedstock.

  15. Fundamental studies of synthesis-gas production based on fluidised-bed gasification of biomass-UCGFunda

    Energy Technology Data Exchange (ETDEWEB)

    Reinikainen, M.; Moilanen, A.; Simell, P.; Hannula, I.; Kurkela, E. (VTT Technical Research Centre of Finland, Espoo (Finland)), e-mail: matti.reinikainen@vtt.fi; Suominen, T. P. (Aabo Akademi, Turku (Finland), Teknisk Kemi och Reaktionsteknik), e-mail: timo.suominen@abo.fi; Linnekoski, J. (Aalto Univ., School of Science and Technology, Espoo (Finland), Lab. of Industrial Chemistry)

    2011-11-15

    The research was directed towards methods of producing transportation bio-fuels via the synthesis-gas route, with emphasis on the synthesis-gas production and gas cleaning steps. The subtopics of the research project were (1) fuel characterisation and ash behaviour in the gasification step, (2) reaction mechanisms related to gas cleaning, (3) evaluations of alternative process configurations and applications and (4) international cooperation. VTT itself financed also two additional subtopics: (5) new analysis techniques and (6) hydrogen from biomass via gasification. The project comprised experimental work, modelling, techno-economic evaluations as well as studies based on literature. The project was steered by a wide industrial consortium and the research work was carried out by VTT, Aalto University and Aabo Akademi. International development in syngas technology was closely monitored in all subtopics as well as by participating in relevant IEA-tasks. More information on the project can be found on project webpage http://www.vtt.fi/proj/ucgfunda/ (orig.)

  16. Thermal decomposition and gasification of biomass pyrolysis gases using a hot bed of waste derived pyrolysis char.

    Science.gov (United States)

    Al-Rahbi, Amal S; Onwudili, Jude A; Williams, Paul T

    2016-03-01

    Chars produced from the pyrolysis of different waste materials have been investigated in terms of their use as a catalyst for the catalytic cracking of biomass pyrolysis gases during the two-stage pyrolysis-gasification of biomass. The chars were produced from the pyrolysis of waste tyres, refused derived fuel and biomass in the form of date stones. The results showed that the hydrocarbon tar yields decreased significantly with all the char materials used in comparison to the non-char catalytic experiments. For example, at a cracking temperature of 800°C, the total product hydrocarbon tar yield decreased by 70% with tyre char, 50% with RDF char and 9% with biomass date stones char compared to that without char. There was a consequent increase in total gas yield. Analysis of the tar composition showed that the content of phenolic compounds decreased and polycyclic aromatic hydrocarbons increased in the product tar at higher char temperatures. PMID:26773946

  17. Soil application of ash produced by low-temperature fluidized bed gasification: effects on soil nutrient dynamics and crop response

    DEFF Research Database (Denmark)

    Müller-Stöver, Dorette Sophie; Ahrenfeldt, Jesper; Holm, Jens Kai;

    2012-01-01

    investigate the effects of the ashes on soil microbiological and chemical properties and on the response of the three crops. The ash treatments were compared with a control treatment that received only nitrogen, magnesium, and sulphur (CO) and a fully fertilized control (COPK). Soil microbial parameters were...... not significantly altered after ash application. SA was generally able to increase the levels of Olsen-P and of the ammonium acetate/acetic acid-extractable K in soil as well as to improve the yield of barley and maize, whereas faba bean did not react positively to ash amendment. CP did not show...... beneficial effects on soil nutrient levels or on crop biomass. We conclude from the results of this study, that—depending on the feedstock used—ashes from LT-CFB gasification of plant biomass can be used to replace mineral fertilizers if they are applied according to their nutrient content, the crop demand...

  18. The development and use of a laboratory scale reactor to study aspects of gasification in an air blown fluidised bed

    Energy Technology Data Exchange (ETDEWEB)

    Cousins, A.; Zhuo, Y.; Reed, G.P.; Paterson, N.; Dugwell, D.R.; Kandiyoti, R. [Imperial College London, London (United Kingdom). Dept of Chemical Engineering

    2006-07-01

    A laboratory scale reactor has been used to study aspects of air blown, spouted bed gasifiers. The effects of operating conditions on the release of fuel-N has been studied using both coal and sewage sludge. The work has clarified the reactions involved and shown that steam has an important effect on the formation of NH{sub 3} from both volatile-N and char-N. The HCN concentration depends strongly on the residence time at temperature and on the presence (and depth) of a char bed. Trace element results indicate that bed temperatures above 900{sup o}C enhanced depletion of Ba, Pb and Zn from the bed residue and their enrichment in the fines. Mercury and selenium were released and their subsequent capture required low temperature filters operating below 120{sup o}C. The reactor was modified to enable char samples to be prepared and collected under controlled conditions. Results show the decreasing reactivity of the char with increasing temperature, time, pressure and particle size. There appears to be an initial decrease in reactivity during pyrolysis and a further longer- term decrease caused by graphitisation. 10 refs., 8 figs., 6 tabs.

  19. An experimental study of the partial oxidation of ethane to ethylene in a shallow fluidized bed reactor

    OpenAIRE

    DANICA BRZIC; DESISLAVA AHCHIEVA; MIRKO PEGLOW; STEFAN HEINRICH

    2007-01-01

    The partial catalytic oxidation of ethane to ethylene was investigated experimentally in a shallow fluidized bed. The performaces of two catalyst types, pure g‑Al2O3 and V2O5/ g-Al2O3 particles 1.8 mm in diameter, were analyzed. A pilot fluidized bed reactor with rectangular cross-section of 100mm´100mm was used. The experiments were carried out under atmospheric pressure in a dilute system under oxygen excess conditions. V2O5/g-Al2O3 showed good catalytic performances regarding ethylene sele...

  20. Gasification of Ligno-Cellulosic Biomass in a Fluidized Bed of Sand and a Mixture of Sand with Dolomitic Limestone

    Czech Academy of Sciences Publication Activity Database

    Pohořelý, Michael; Jeremiáš, Michal; Kameníková, Petra; Svoboda, Karel; Skoblia, S.; Beňo, Z.; Durda, Tomáš; Barger, A.; Šyc, Michal; Hartman, Miloslav; Punčochář, Miroslav

    Vienna : Technische Universität Wien, 2013 - (Hofbauer, H.; Fuchs, M.), s. 1-15 ISBN 978-3-9502754-8-3. [International Conference on Polygeneration Strategies 13. Vienna (AT), 03.09.2013-05.09.2013] R&D Projects: GA TA ČR TA01020366 Grant ostatní: RFCS(XE) RFCR-CT-2010-00009 Institutional support: RVO:67985858 Keywords : dolomitic limestone * fluidized-bed gasifier * biomass Subject RIV: DK - Soil Contamination ; De-contamination incl. Pesticides

  1. Catalytic Partial Oxidation of Methane with Air to Syngas in a Pilot-Plant-Scale Spouted Bed Reactor

    Institute of Scientific and Technical Information of China (English)

    魏伟胜; 徐建; 方大伟; 鲍晓军

    2003-01-01

    On the basis of hydrodynamic and scaling-up studies, a pilot-plant-scale thermal spouted bed reactor (50 mm in ID and 1500 mm in height) was designed and fabricated by scaling-down cold simulators. It was tested for making syngas via catalytic partial oxidation (CPO) of methane by air. The effects of various operating conditions such as operating pressure and temperature, feed composition, and gas flowrate etc. on the CPO process were investigated. CH4 conversion of 92.20% and selectivity of 92.3% and 83.30/0 to CO and H2, respectively, were achieved at the pressure of 2.1 MPa. It was found that when the spouted bed reactor was operated within the stable spouting flow regime, the temperature profiles along the bed axis were much more uniform than those operated within the fixed-bed regime. The CH4 conversion and syngas selectivity were found to be close to thermodynamic equilibrium limits. The results of the present investigation showed that spouted bed could be considered as a potential type of chemical reactor for the CPO process of methane.

  2. Gasificación con aire en lecho fluidizado de los residuos sólidos del proceso industrial de la naranja//Air gasification in fluidized bed of solid residue the orange industrial process

    Directory of Open Access Journals (Sweden)

    Leonardo Aguiar-Trujillo

    2012-12-01

    Full Text Available La industria procesadora de la naranja genera elevados volúmenes de residuos sólidos. Este residuo se ha utilizado en la alimentación animal y en procesos bioquímicos; pero no se ha aprovechado a través de la gasificación. El objetivo del trabajo fue determinar el aporte energético por medio del proceso de gasificación, realizándose estudios de los residuos sólidos de naranja, utilizando aire en reactor de lecho fluidizado burbujeante (variando la temperatura de gasificación, relación estequiométrica y altura del lecho. En el proceso se utilizó un diseño de experimento factorial completo de 2k, valorando la influencia de las variables independientes y sus interacciones en las respuestas, con un grado de significación del 95 %. Se obtuvieron los parámetros para efectuar el proceso de gasificación de los residuos sólidos de naranja, obteniendo un gas de bajo poder calórico, próximo a 5046 kJ/m3N, demostrando sus cualidades para su aprovechamiento energético.Palabras claves: gasificación con aire, lecho fluidizado, residuo de naranja._______________________________________________________________________________AbstractThe orange industrial process generates high volumes of solid residue. This residue has been used as complement in the animal feeding and biochemical processes; but it has not taken advantage through of the gasification process. The objective of the work was to determine the energy contribution by means ofthe gasification process, were carried out studies of the orange solid residue, using air in reactor of bubbling fluidized bed (varying the gasification temperature, air ratio and bed height. In the process a design of complete factorial experiment of 2k, was used, valuing the influence of the independent variables and its interactions in the answers, using a confidence level of 95 %. Were obtained the parameters to make the process of gasification of the orange solid residue, obtaining a gas of lower heating

  3. 增压喷动流化床中煤半气化数值模拟%Numerical Simulation of Pressurized Spouted Fluidized Bed for Coal Semi-Gasification

    Institute of Scientific and Technical Information of China (English)

    周山明; 金保升; 章名耀

    2002-01-01

    本文对增压喷动流化床中煤半气化进行了模拟,在模型中考虑了增压喷动流化床的物理特性、化学反应、能量平衡,对床压、床温、空煤比,汽煤比对生成煤气成分的影响进行了研究.计算结果表明增压喷动流化床中床压、床温对煤的半气化影响较强.%Numerical simulation study is conducted for a pressurized spouted-fluidized bed coal carbonizer, in which hydrodynamics of pressurized spouted-fluidized bed, chemical reactions and energy balance are taken into account. The effect of operating conditions such as bed pressure, air and steam mass flow ratio, temperature on product compositions in the bed is investigated. According to the calculated results, bed pressure and bed temperature have the key effects on coal semi-gasification.

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

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

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

  5. A comparison of Rh/CeO2/SiO2 catalysts with steam reforming catalysts, dolomite and inert materials as bed materials in low throughput fluidized bed gasification systems

    International Nuclear Information System (INIS)

    The gasification of cedar wood in the presence of Rh/CeO2/SiO2 has been conducted in the laboratory scale fluidized bed reactor using air as a gasifying agent at low temperatures (823-973 K) in order to produce high-quality fuel gas for gas turbine for power generation. The performance of the Rh/CeO2/SiO2 catalyst has been compared with conventional catalysts such as commercial steam reforming catalyst G-91, dolomite and noncatalyst systems by measurements of the cold gas efficiency, tar concentration, carbon conversion to gas and gas composition. The tar concentration was completely negligible in the Rh/CeO2/SiO2-catalyzed product gas whereas it was about 30, 113, and 139 g/m3 in G-91, dolomite and noncatalyzed product gas, respectively. Since the carbon conversion to useful gas such as CO, H2, and CH4 are much higher on Rh/CeO2/SiO2 catalyst than others at 873 K, the cold gas efficiency is much higher (71%) in this case than others. The hydrogen content in the product gas is much higher (>24 vol%) than the specified level (>10 vol%) for efficient combustion in the gas turbine engine. The char and coke formation is also very low on Rh/CeO2/SiO2 catalyst than on the conventional catalysts. Although the catalyst surface area was slightly decreased after using the same catalyst in at least 20 experiments, the deactivation problem was not severe

  6. 气流床气化洗涤工艺分析%Analysis of Washing Process of Entrained Bed Gasification Technology

    Institute of Scientific and Technical Information of China (English)

    李仕超

    2015-01-01

    介绍了气化炉内灰和渣的形成过程,在分析GE 水煤浆气化、四喷嘴水煤浆气化、GSP干煤粉气化和Choren干粉煤气化等技术的细灰洗涤工艺流程基础上,通过设计和实际生产的对比,提出了优化气化洗涤工艺的思路.%This article introduces the formation process of ash and slag in gasifier .Based on the analysis of the fine ash washing processes of GE Gasifica-tion Process, four-burner gasification process, GSP and Choren Gasification Process, and comparison of the design and the actual production, this paper proposes the optimized ideas of gasification washing process.

  7. An experimental study of the partial oxidation of ethane to ethylene in a shallow fluidized bed reactor

    Directory of Open Access Journals (Sweden)

    DANICA BRZIC

    2007-02-01

    Full Text Available The partial catalytic oxidation of ethane to ethylene was investigated experimentally in a shallow fluidized bed. The performaces of two catalyst types, pure g‑Al2O3 and V2O5/ g-Al2O3 particles 1.8 mm in diameter, were analyzed. A pilot fluidized bed reactor with rectangular cross-section of 100mm´100mm was used. The experiments were carried out under atmospheric pressure in a dilute system under oxygen excess conditions. V2O5/g-Al2O3 showed good catalytic performances regarding ethylene selectivity. The influence of the temperature (in the range of 400–600 °C and the contact time (in the range of 35 – 85 kg sm-3 on the conversion of ethane and the selectivity to ethylene was analyzed. The highest yield of ethylene was 18 %.

  8. Pressurized Ash Fusion Fluidized Bed Pulverized Coal Gasification Technology:its Superiority and Application Orientation%加压灰融聚流化床粉煤气化技术优势及应用方向

    Institute of Scientific and Technical Information of China (English)

    毕可军; 毛少祥; 孔北方; 柏林红

    2013-01-01

    An introduction is given to the technological features and process flowsheet of ash fusion fluidized bed pulverized coal gasification,and optimized process and technological superiority are analyzed in depth of the pressurized gasification technology.Based on its characteristics,follow-up process schemes are proposed for its use in gasification of high-sulfur pulverized coal for the production of methanol,hydrogen and IGCC.%介绍了灰融聚流化床粉煤气化技术特点、工艺流程,探析了加压灰融聚流化床粉煤气化技术的优化工艺、技术优势.根据加压灰融聚流化床粉煤气化技术的特点,提出了该技术应用于高硫粉煤气化制甲醇、制氢、整体煤气化联合循环发电(IGCC)的后续工艺方案.

  9. Effect of a Reactivation strategy based on partial bio catalyst replacement on the performance of a fungal fluidized bed bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Ortega-Clemente, A.; Robledo-Narvaez, P.; Barrera-Cortes, J.; Poggi-Varaldo, H. M.

    2009-07-01

    The Mexican pulp and paper industry discharges approximately 12% of the annual industrial discharges and holds a second position in the ranking of main water industrial polluters in Mexico. Their wastewaters are characteristically recalcitrant and toxic. The objective of this work was to evaluate the effectiveness of two operational strategies on the performance of two fungal fluidized bed reactor (FBR) for the post-treatment of anaerobically weal black liquor systems (AP-WBL) without supplementation of soluble carbohydrates, i. e. Strategy 1 (continuous operation with the same original, fungal bio catalysts and eventual spikes of protease inhibitor and glucose), and Strategy 2 operation with partial exchange of bio catalysts. (Author)

  10. Kinetics of gasification and combustion of residues, biomass and coal in a bubbling fluidized bed; Die Kinetik der Vergasung und Verbrennung unterschiedlicher Abfaelle, Biomassen und Kohlen in der blasenbildenden Wirbelschicht

    Energy Technology Data Exchange (ETDEWEB)

    Hamel, S.; Krumm, W. [Siegen Univ. (Gesamthochschule) (Germany). Lehrstuhl fuer Energie- und Umweltverfahrenstechnik

    1998-09-01

    The combustion and gasification characteristics of Rhenish brown coal, domestic waste, waste plastics, wood and sewage sludge were investigated in a bubbling atmospheric fluidized bed in the laboratory scale. The materials were pyrolyzed in the fluidized bed in a nitrogen atmosphere. The residual coke was combuted in the presence of oxygen with varying operating parameters or else gasified in the presence of carbon dioxide. The different materials were characterized by global combustion rates, and kinetic parameters were determined for residual coke combustion. (orig.) [Deutsch] Das Verbrennungs- und Vergasungsverhalten von Rheinischer Braunkohle, Hausmuell, Restkunststoff, Holz und Klaerschlamm wurde in einer blasenbildenden, atmosphaerischen Laborwirbelschicht untersucht. Die Einsatzstoffe wurden in der mit Stickstoff fluidisierten Wirbelschicht pyrolysiert. Der verbleibende Restkoks wurde anschliessend unter Variation der Betriebsparameter mit Sauerstoff verbrannt oder mit Kohlendioxid vergast. Die unterschiedlichen Einsatzstoffe wurden durch globale Vebrennungsraten charakterisiert. Fuer die Restkoksverbrennung wurden kinetische Parameter ermittelt. (orig.)

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

    International Nuclear Information System (INIS)

    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

  12. Low rank coal – CO2 gasification: Experimental study, analysis of the kinetic parameters by Weibull distribution and compensation effect

    International Nuclear Information System (INIS)

    Gasification is generally considered as the most effective for low rank coal exploitation and CO2 gasification offers the advantage of upgrading an environmentally detrimental gas. Isothermal CO2 gasification tests of Greek low rank coal were performed in a tubular fixed bed reactor, to study the effect of the various reaction conditions. Greek lignite was quite reactive with CO2, resulting in high conversions even at short reaction times, while the obtained chars remained reactive after devolatilisation, as the continuous increase of conversion indicated. Conversion was very sensitive to temperature due to both pyrolysis and C–CO2 reactions, and for the granulometries studied (up to 1000 μm) the gasification rate was independent of particle size. CO2 partial pressure affected the gasification rate at low CO2 partial pressures, since the reactivity of lignite remained high (conversion ∼85% w/w daf) even for 0.25 atm CO2 partial pressure. The presence of CO retarded the reaction and the gasification rate decreased rapidly as the concentration of CO increased. The first order Volume Reaction Model (VMR) adopted was proven quite effective in describing the experimental results. Experimental results showed that the activation energy (E) varied with time, passing through a wide maximum between 10 and 15 min. The pre-exponential factor (k0) follows the behaviour of the activation energy, however, it exhibits a more sharp maximum at the same time region. The variations of the kinetic parameters with time could be attributed to the different nature of carbon atoms gasified and the changes of the number of active collisions, as the gasification reaction proceeds. As the gasification reaction advanced the Arrhenius parameters (E and k0) increased or decreased simultaneously, exhibiting a compensation effect. The probability density function (pdf) of the Weibull distribution was employed successfully to depict the variations of the kinetic parameters, E and k0.

  13. 双流化床生物质气化及CO2捕获的模拟%Simulation of biomass gasification in dual fluidized beds with CO2 capture

    Institute of Scientific and Technical Information of China (English)

    夏小宝; 解东来; 叶根银

    2011-01-01

    用Aspen Plus建立了双流化床气化和燃烧模型,对生物质在双流化床中气化及CaO吸收合成气中的CO2过程进行了模拟研究;探讨不同反应条件:气化温度、蒸汽与生物质的质量配比(S/B)以及CaO循环量与生物质的质量配比(Ca/B)对合成气成分的影响,为该类型工业反应器的研发提供了理论依据.模拟分析结果表明:气化温度低于700℃时,CaO能很好地吸收气化过程中产生的CO2并促进平衡反应向产氢方向进行;在温度为650℃及CaO作用下,S/B在0.6~1.7内对合成气成分的影响不大;CaO的加入能够有效地改善合成气的组成,合成气中氢气浓度能达到95%以上,氢气产量达到52 mol/kg.%An Aspen model was built to simulate the gasification and combustion processes in the dual fluidized beds. The processes of biomass gasification and CO2 adsorption by CaO were stud-ied.The effects of gasification temperature, biomass ratio to steam (S/B), CaO to biomass ratio (Ca/B) on the syngas composition were discussed. Simulation results indicated that CaO can effectively capture the CO2 in the syngas and shift the thermodynamics balance to hydrogen production direction when the gasification temperature was below 700 X.. Steam to biomass ratio (0.6-1.7) has very little influences on the syn-gas composition under the gasification temperature of 650 ℃ and with the existence of CaO. The addition and circulation of CaO can effectively improve the syngas composition. The hydrogen concentration in the syngas can reach up to 95% and hydrogen production rate reach 52 mol/kg.

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

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Guohai; Vimalchand, Pannalal; Peng, WanWang

    2015-11-13

    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 1150.degree. C. to 1500.degree. C. range as well as in excess of 1500.degree. 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.

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

    Institute of Scientific and Technical Information of China (English)

    BU Xue-peng; XU Zhen-gang

    2004-01-01

    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.

  16. Effect of partial replacement of diesel or biodiesel with gas from biomass gasification in a diesel engine

    International Nuclear Information System (INIS)

    The injected diesel fuel used in a diesel engine was partially replaced with biomass-derived gas through the intake port, and the effect on performance and pollutant emissions was studied. The experimental work was carried out in a supercharged, common-rail injection, single-cylinder diesel engine by replacing diesel fuel up to 20% (by energy), keeping constant the engine power. Three engine loads (60, 90, 105 Nm), three different EGR (exhaust gas recirculation) ratios (0, 7.5, 15%) and two intake temperatures (45, 60 °C) were tested. Finally, some of the tested conditions were selected to replace diesel injection fuel with biodiesel injection. Although the brake thermal efficiency was decreased and hydrocarbons and carbon monoxide emissions increased with increasing fuel replacement, particulate emissions decreased significantly and NOx emissions decreased slightly at all loads and EGR ratios. Thermodynamic diagnostic results showed higher premixed ratio and lower combustion duration for increasing diesel fuel replacement. High EGR ratios improved both engine performance and emissions, especially when intake temperature was increased, which suggest removing EGR cooling when diesel fuel is replaced. Finally, when biodiesel was used instead of diesel fuel, the gas replacement improved the efficiency and reduced the hydrocarbon, carbon monoxide and particulate emissions. - Highlights: • Replacing injected fuel with gas permits an efficient valorization of waste biomass. • Inlet gas was inefficiently burned after the end of liquid fuel injection. • Engine parameters were combined to simultaneously reduce particle and NOx emissions. • Hot EGR (exhaust gas recirculation) and biodiesel injection are proposed to improve efficiency and emissions

  17. Comparison for CO Preparation by Oxygen Surplus Gasification Method in Fixed Bed with Using Pressure Variation Adsorption Method%固定床富氧造气法与变压吸附法制备 CO 的比较

    Institute of Scientific and Technical Information of China (English)

    张雷; 陆丽萍

    2013-01-01

    分别介绍了固定床富氧造气法与变压吸附法制备CO的工艺原理和工艺流程;从装置投资、生产操作、运行成本等方面对比了2种制备方法的优点和缺点。%Author has separately introduced the process principle and process flow for preparing CO by oxygen surplus gasification method in fixed bed and by pressure variation adsorption method; has compared the advantages and shortages of two kinds of preparing methods from aspects of investment of device, productive operation, operating cost etc.

  18. GASIFICATION FOR DISTRIBUTED GENERATION

    Energy Technology Data Exchange (ETDEWEB)

    Ronald C. Timpe; Michael D. Mann; Darren D. Schmidt

    2000-05-01

    evaluated through reactivity and product composition were carried out on thermogravimetric analysis (TGA) equipment. These tests were evaluated and then followed by bench-scale studies at 1123 K using an integrated bench-scale fluidized-bed gasifier (IBG) which can be operated in the semicontinuous batch mode. Products from tests were solid (ash), liquid (tar), and gas. Tar was separated on an open chromatographic column. Analysis of the gas product was carried out using on-line Fourier transform infrared spectroscopy (FT-IR). For selected tests, gas was collected periodically and analyzed using a refinery gas analyzer GC (gas chromatograph). The solid product was not extensively analyzed. This report is a part of a search into emerging gasification technologies that can provide power under 30 MW in a distributed generation setting. Larger-scale gasification has been used commercially for more than 50 years to produce clean synthesis gas for the refining, chemical, and power industries, and it is probable that scaled-down applications for use in remote areas will become viable. The appendix to this report contains a list, description, and sources of currently available gasification technologies that could be or are being commercially applied for distributed generation. This list was gathered from current sources and provides information about the supplier, the relative size range, and the status of the technology.

  19. Fluidized Bed Gasification as a Mature And Reliable Technology for the Production of Bio-Syngas and Applied in the Production of Liquid Transportation Fuels: A Review

    OpenAIRE

    Verkooijen, Adrian H. M.; Wiebren de Jong; Marcin Siedlecki

    2011-01-01

    Biomass is one of the renewable and potentially sustainable energy sources and has many possible applications varying from heat generation to the production of advanced secondary energy carriers. The latter option would allow mobile services like the transportation sector to reduce its dependency on the fossil fuel supply. This article reviews the state-of-the-art of the fluidization technology applied for the gasification of biomass aimed at the production of gas for subsequent synthesis of ...

  20. Second stage gasifier in staged gasification and integrated process

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Guohai; Vimalchand, Pannalal; Peng, Wan Wang

    2015-10-06

    A second stage gasification unit in a staged gasification integrated process flow scheme and operating methods are disclosed to gasify a wide range of low reactivity fuels. The inclusion of second stage gasification unit operating at high temperatures closer to ash fusion temperatures in the bed provides sufficient flexibility in unit configurations, operating conditions and methods to achieve an overall carbon conversion of over 95% for low reactivity materials such as bituminous and anthracite coals, petroleum residues and coke. The second stage gasification unit includes a stationary fluidized bed gasifier operating with a sufficiently turbulent bed of predefined inert bed material with lean char carbon content. The second stage gasifier fluidized bed is operated at relatively high temperatures up to 1400.degree. C. Steam and oxidant mixture can be injected to further increase the freeboard region operating temperature in the range of approximately from 50 to 100.degree. C. above the bed temperature.

  1. Pulsed combustion process for black liquor gasification

    Energy Technology Data Exchange (ETDEWEB)

    Durai-Swamy, K.; Mansour, M.N.; Warren, D.W.

    1991-02-01

    The objective of this project is to test an energy efficient, innovative black liquor recovery system on an industrial scale. In the MTCI recovery process, black liquor is sprayed directly onto a bed of sodium carbonate solids which is fluidized by steam. Direct contact of the black liquor with hot bed solids promotes high rates of heating and pyrolysis. Residual carbon, which forms as a deposit on the particle surface, is then gasified by reaction with steam. Heat is supplied from pulse combustor resonance tubes which are immersed within the fluid bed. A portion of the gasifier product gas is returned to the pulse combustors to provide the energy requirements of the reactor. Oxidized sulfur species are partially reduced by reaction with the gasifier products, principally carbon monoxide and hydrogen. The reduced sulfur decomposed to solid sodium carbonate and gaseous hydrogen sulfide (H{sub 2}S). Sodium values are recovered by discharging a dry sodium carbonate product from the gasifier. MTCI's indirectly heated gasification technology for black liquor recovery also relies on the scrubbing of H{sub 2}S for product gases to regenerate green liquor for reuse in the mill circuit. Due to concerns relative to the efficiency of sulfur recovery in the MTCI integrated process, an experimental investigation was undertaken to establish performance and design data for this portion of the system.

  2. Fluidized-bed gasification under pressure of fuel element graphite in an industrial-scale reprocessing plant for HTR fuel elements

    International Nuclear Information System (INIS)

    In the head end of nuclear fuel reprocessing, the graphite cladding of spent HTR fuel elements is separated from the fissible material. Fluidized-bed combustion has some advantages over fixed-bed combustion. It is the method of choice in the design of a large-scale plant of 50.000 MWe HTR power. By means of an excess pressure of about 5 bar, a threefold increase in efficiency of a fluidized-bed ractor can be achieved. For an optimum layout of a prototype combustion plant, jacket cooling and internal heat exchangers are required. For an assessment of fluidized-bed combustion under pressure as a process step in the head end of a reprocessing plant, the author presents heat transfer calculations on the basis of a varying specific combustion load and investigations of the necessary peripheral equipment (reactor vessel, dust removal systems, gas supply and distribution, etc.) in several model set-ups. (RB)

  3. Chemical-looping gasification of biomass in a 10k Wth interconnected fluidized bed reactor using Fe2 O3/Al2 O3 oxygen carrier

    Institute of Scientific and Technical Information of China (English)

    HUSEYIN Sozen; WEI Guo-qiang; LI Hai-bin; HE Fang; HUANG Zhen

    2014-01-01

    The aim of this research is to design and operate a 10 kW hot chemical-looping gasification ( CLG) unit using Fe2 O3/Al2 O3 as an oxygen carrier and saw dust as a fuel. The effect of the operation temperature on gas composition in the air reactor and the fuel reactor, and the carbon conversion of biomass to CO2 and CO in the fuel reactor have been experimentally studied. A total 60 h run has been obtained with the same batch of oxygen carrier of iron oxide supported with alumina. The results show that CO and H2 concentrations are increased with increasing temperature in the fuel reactor. It is also found that with increasing fuel reactor temperature, both the amount of residual char in the fuel reactor and CO2 concentration of the exit gas from the air reactor are degreased. Carbon conversion rate and gasification efficiency are increased by increasing temperature and H2 production at 870 ℃reaches the highest rate. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and BET-surface area tests have been used to characterize fresh and reacted oxygen carrier particles. The results display that the oxygen carrier activity is not declined and the specific surface area of the oxygen carrier particles is not decreased significantly.

  4. Partial Oxidation of Hydrocarbons in a Segmented Bed Using Oxide-based Catalysts and Oxygen-conducting Supports

    Science.gov (United States)

    Smith, Mark W.

    Two objectives for the catalytic reforming of hydrocarbons to produce synthesis gas are investigated herein: (1) the effect of oxygen-conducting supports with partially substituted mixed-metal oxide catalysts, and (2) a segmented bed approach using different catalyst configurations. Excess carbon deposition was the primary cause of catalyst deactivation, and was the focus of the experiments for both objectives. The formation and characterization of deposited carbon was examined after reaction for one of the selected catalysts to determine the quantity and location of the carbon on the catalyst surface leading to deactivation. A nickel-substituted barium hexaaluminate (BNHA), with the formula BaAl 11.6Ni0.4O18.8, and a Rh-substituted lanthanum zirconate pyrochlore (LCZR) with the formula La1.89Ca0.11 Zr1.89Rh0.11, were combined with two different doped ceria supports. These supports were gadolinium-doped ceria (GDC) and zirconium-doped ceria (ZDC). The active catalyst phases were combined with the supports in different ratios using different synthesis techniques. The catalysts were characterized using several different techniques and were tested under partial oxidation (POX) of n-tetradecane (TD), a diesel fuel surrogate. It was found that the presence of GDC and ZDC reduced the formation of carbon for both catalysts; the optimal ratio of catalyst to support was different for the hexaaluminate and the pyrochlore; a loading of 20 wt% of the pyrochlore with ZDC produced the most stable performance in the presence of common fuel contaminants (>50 h); and, the incipient wetness impregnation synthesis method of applying the active catalyst to the support produced more stable product yields than the catalyst prepared by a solid-state mixing technique. Different hexaaluminate and pyrochlore catalysts were used in different configurations in a segmented bed approach. The first strategy was to promote the indirect reforming mechanism by placing a combustion catalyst in the

  5. Radiofrequency Energy in Hepatic Bed during Partial Cystectomy for Hydatid Liver Disease: Standing Out from the Usual Conservative Surgical Management

    Science.gov (United States)

    Dimitrokallis, Nikolaos; Sakarellos, Panagiotis; Griniatsos, John

    2016-01-01

    Background. Surgical treatment of hydatid liver disease (HLD) is divided into conservative and radical procedures. While conservative techniques are easier and faster to perform, there is an emerging need to reduce their morbidity and recurrence rates. Our aim was to present and evaluate the efficiency and safety of the application of radiofrequency energy (TissueLink® and Aquamantys® systems) in hepatic bed during partial cystectomy. Materials and Methods. Eighteen consecutive patients with hydatid liver cysts were referred to our department between April 2006 and June 2014. Data about demographics, mortality, morbidity, and recurrence rate were obtained and analyzed retrospectively. Results. The mean follow-up was 38 months (range: 4–84 months). The postoperative course of most patients was uneventful. One case of recurrence was found in our series in a patient with 4 cysts in the right lobe, 3 years after initial treatment. He was reoperated on with the same method. Conclusions. Saline-linked RF energy seems to be an effective means to be employed in conservative surgical procedures of HLD, with satisfactory postoperative morbidity. Recurrence rates appear to be low, but further follow-up is needed in order to draw safer conclusions. PMID:27525000

  6. Axial Changes of Catalyst Structure and Temperature in a Fixed-Bed Microreactor During Noble Metal Catalysed Partial Oxidation of Methane

    DEFF Research Database (Denmark)

    Hannemann, S.; Grunwaldt, Jan-Dierk; Kimmerle, B.;

    2009-01-01

    -line mass spectrometry. This experimental strategy allowed collecting data on the structure of the noble metal (oxidation state) and the temperature along the catalyst bed. The reaction was investigated in a fixed-bed quartz microreactor (1-1.5 mm diameter) following the catalytic performance by on-line gas...... exothermic methane oxidation was too strong. The results indicate that in the oxidized zone mainly combustion of methane occurs, whereas in the reduced part direct partial oxidation and reforming reactions prevail. The results demonstrate how spatially resolved spectroscopy can help in understanding...

  7. Techno Economic Analysis of Hydrogen Production by gasification of biomass

    Energy Technology Data Exchange (ETDEWEB)

    Francis Lau

    2002-12-01

    Biomass represents a large potential feedstock resource for environmentally clean processes that produce power or chemicals. It lends itself to both biological and thermal conversion processes and both options are currently being explored. Hydrogen can be produced in a variety of ways. The majority of the hydrogen produced in this country is produced through natural gas reforming and is used as chemical feedstock in refinery operations. In this report we will examine the production of hydrogen by gasification of biomass. Biomass is defined as organic matter that is available on a renewable basis through natural processes or as a by-product of processes that use renewable resources. The majority of biomass is used in combustion processes, in mills that use the renewable resources, to produce electricity for end-use product generation. This report will explore the use of hydrogen as a fuel derived from gasification of three candidate biomass feedstocks: bagasse, switchgrass, and a nutshell mix that consists of 40% almond nutshell, 40% almond prunings, and 20% walnut shell. In this report, an assessment of the technical and economic potential of producing hydrogen from biomass gasification is analyzed. The resource base was assessed to determine a process scale from feedstock costs and availability. Solids handling systems were researched. A GTI proprietary gasifier model was used in combination with a Hysys(reg. sign) design and simulation program to determine the amount of hydrogen that can be produced from each candidate biomass feed. Cost estimations were developed and government programs and incentives were analyzed. Finally, the barriers to the production and commercialization of hydrogen from biomass were determined. The end-use of the hydrogen produced from this system is small PEM fuel cells for automobiles. Pyrolysis of biomass was also considered. Pyrolysis is a reaction in which biomass or coal is partially vaporized by heating. Gasification is a more

  8. 灰融聚流化床粉煤气化技术应用及节能减排措施%Use of Agglomerating Ash Fluid Bed Pulverized Coal Gasification Technology and Measures for Energy Saving and Discharge Reduction

    Institute of Scientific and Technical Information of China (English)

    毕可军

    2011-01-01

    The agglomerating ash fluid bed pulverized coal gasification technology is described, its special features, process flow and the measures taken for energy saving and discharge reduction, with results. A comparison is given of the gasifiers at atmospheric and 1. 0 Mpa pressures for the production of 1 000 m3 of gas with the UGI oxygen-enriched gasifier, and the results show that the energy consumption of the atmospheric fluid bed gasifier is slightly lower than that of the UGI oxygen-enriched gasifier, while the 1.0 Mpa pressurized one is more advantageous than the atmospheric one in terms of energy saving.%介绍了灰融聚流化床粉煤气化技术的特点、工艺流程及采取的节能减排措施和效果.对常压和加压1.0 MPa灰融聚流化床粉煤气化炉生产1 000m3煤气的能耗分别与UGI富氧气化炉进行比较,结果表明:常压灰融聚流化床粉煤气化技术的能耗略低于UGI富氧气化技术,而加压1.0 MPa灰融聚流化床粉煤气化技术比常压灰融聚流化床粉煤气化技术在节能方面更具优势.

  9. Estudio mecánico e hidrodinámico de un reactor de gasificación de lecho fluidizado. // Mechanic and hydrodynamic study of a fluidized bed gasification reactor.

    Directory of Open Access Journals (Sweden)

    W. Rosales

    2008-01-01

    Full Text Available Se realizó una simulación mediante Elementos Finitos y CFD de un prototipo de gasificador experimental a partir de unageometría propuesta. Se abordan aspectos termomecánicos, al calcularse las deformaciones originadas en el equipo,producto de su peso, en las condiciones de emplazamiento y la carga térmica a la que se somete. También se considera elflujo multifásico gas-sólido presente en el lecho fluidizado, se determina el rango de presiones y velocidades de trabajo deldispositivo, y se estudia la evolución del flujo. Para ello se utiliza el modelo de fuerza de arrastre y presión de sólido deGidaspow, así como los criterios de velocidad mínima de fluidización de Wen & Yu y Kunii & Levenspiel.Palabras claves: Gasificación, lecho fluidizado, CFD, FEM, flujo multifásico.______________________________________________________________________________Abstract.A Finite Element and CFD simulations were conducted to a prototype of experimental gasifier, starting from a proposedgeometry. Thermomechanic aspects are briefed, calculating the reactor deformation, due to its weight and the thermic load.The gas-solid multiphase flow, present on the fluidized bed was also considered, the working range for the pressure andvelocity fields were determined and the flow evolution was studied. The drag force and solid pressure models byGidaspow, and the minimum fluidization velocity criteria, by Wen & Yu and Kunii & Levenspiel were used.Key words: gasification, fluidized bed, CFD, Finite Element, Multiphase Flow.

  10. Pressurized gasification of biomass - complete power plant technology; Biomassan paineistettu kaasutus valmis voimalaitostekniikaksi

    Energy Technology Data Exchange (ETDEWEB)

    Virkkunen, L. [Enviropower Oy, Tampere (Finland)

    1994-12-31

    Enviropower Oy, which is an affiliate of Tampella Power Oy, has just finished a large gasification test program at the 20 MW test power plant situated at Tampere. Total amount of 3 000 m{sup 3} of finnish mixed wood chips were gasified during the tests in 1993. Enviropower has been the first which has gasified biomass using large-scale pressurized system. The technology can be applied both for biomass and coal. This so called multi-fuel boiler increases the possibilities to use biomass as fuels, and also improves the competitivity of it because it makes the merely utilization of biomass possible also in the coal fired power plants. Gasification technique, based on wood, waste wood and peat, will be commercialized fast in the plants which partially utilizes also other fuels than coal. The most economical way to increase the utilization of biomass is to gasify it with other fuels using the new technology. The gasification combined cycle power plant, based on pressurized fluidized bed gasification can coarsely be compared with common natural gas combined cycle power plants. Gas, produced by gasification from solid fuels, is used as fuel instead of natural gas. The process is very simple. Coal, waste wood, peat and other solid fuels are heated in a fluidized bed type pressurized reactor at the temperature of about one thousand degrees celsius, under the conditions in which the fuels are gasified. The sulfur, the dust and the other harmful compounds are removed from the product gas, and the clean gas is combusted in a gas turbine and the heat produced in the process is converted into electric power using heat recovery boiler and steam turbine

  11. Gasification performance of switchgrass pretreated with torrefaction and densification

    International Nuclear Information System (INIS)

    Highlights: • We evaluated effects of switchgrass torrefaction and densification on the syngas. • The pretreatment and gasification temperature significantly effected performance. • Combined torrefaction and densification had the highest gas yield and efficiencies. • Increase in gasification temperature increased the gas yield and efficiencies. - Abstract: The purpose of this study was to investigate gasification performance of four switchgrass pretreatments (torrefaction at 230 and 270 °C, densification, and combined torrefaction and densification) and three gasification temperatures (700, 800 and 900 °C). Gasification was performed in a fixed-bed externally heated reactor with air as an oxidizing agent. Switchgrass pretreatment and gasification temperature had significant effects on gasification performance such as gas yields, syngas lower heating value (LHV), and carbon conversion and cold gas efficiencies. With an increase in the gasification temperature, yields of H2 and CO, syngas LHV, and gasifier efficiencies increased whereas CH4, CO2 and N2 yields decreased. Among all switchgrass pretreatments, gasification performance of switchgrass with combined torrefaction and densification was the best followed by that of densified, raw and torrefied switchgrass. Gasification of combined torrefied and densified switchgrass resulted in the highest yields of H2 (0.03 kg/kg biomass) and CO (0.72 kg/kg biomass), highest syngas LHV (5.08 MJ m−3), CCE (92.53%), and CGE (68.40%) at the gasification temperature of 900 °C

  12. Gasification biochar as a valuable by-product for carbon sequestration and soil amendment

    OpenAIRE

    Hansen, Veronika; Müller-Stöver, Dorette; Ahrenfeldt, Jesper; Holm, Jens Kai; Henriksen, Ulrik Birk; Hauggaard-Nielsen, Henrik

    2015-01-01

    Thermal gasification of various biomass residues is a promising technology for combining bioenergy production with soil fertility management through the application of the resulting biochar as soil amendment. In this study, we investigated gasification biochar (GB) materials originating from two major global biomass fuels: straw gasification biochar (SGB) and wood gasification biochar (WGB), produced by a Low Temperature Circulating Fluidized Bed gasifier (LT-CFB) and a TwoStage gasifier, res...

  13. Biomass gasification for energy production

    Energy Technology Data Exchange (ETDEWEB)

    Lundberg, H.; Morris, M.; Rensfelt, E. [TPS Termiska Prosesser Ab, Nykoeping (Sweden)

    1997-12-31

    Biomass and waste are becoming increasingly interesting as fuels for efficient and environmentally sound power generation. Circulating fluidized bed (CFB) gasification for biomass and waste has been developed and applied to kilns both in the pulp and paper industry and the cement industry. A demonstration plant in Greve-in- Chianti, Italy includes two 15 MW{sub t}h RDF-fuelled CFB gasifiers of TPS design, the product gas from which is used in a cement kiln or in steam boiler for power generation. For CFB gasification of biomass and waste to reach a wider market, the product gas has to be cleaned effectively so that higher fuel to power efficiencies can be achieved by utilizing power cycles based on engines or gas turbines. TPS has developed both CFB gasification technology and effective secondary stage tar cracking technology. The integrated gasification - gas-cleaning technology is demonstrated today at pilot plant scale. To commercialise the technology, the TPS`s strategy is to first demonstrate the process for relatively clean fuels such as woody biomass and then extend the application to residues from waste recycling. Several demonstration projects are underway to commercialise TPS`s gasification and gas cleaning technology. In UK the ARBRE project developed by ARBRE Energy will construct a gasification plant at Eggborough, North Yorkshire, which will provide gas to a gas turbine and steam turbine generation system, producing 10 MW and exporting 8 Mw of electricity. It has been included in the 1993 tranche of the UK`s Non Fossil Fuel Obligation (NFFO) and has gained financial support from EC`s THERMIE programme as a targeted BIGCC project. (author)

  14. Kinetics of woodchips char gasification with steam and carbon dioxide

    International Nuclear Information System (INIS)

    Kinetics of woodchips char gasification has been examined. Steam and CO2 were used as the gasifying agents. Differences and similarities between kinetics of steam gasification and CO2 gasification have been discussed. Comparison was conducted in terms of gasification duration, evolution of reaction rate with time and/or conversion, and effect of partial pressure on reaction rate. Reactor temperature was maintained at 900 oC. Partial pressure of gasifying agents varied from 1.5 bars to 0.6 bars in intervals of 0.3 bars. Steam and CO2 flow rates were chosen so that both gasifying agents had equal amount of oxygen content. CO2 gasification lasted for about 60 min while steam gasification lasted for about 22 min. The average reaction rate for steam gasification was almost twice that of CO2. Both reaction rate curves showed a peak value at certain degree of conversion. For steam gasification, the reaction rate peak was found to be at a degree of conversion of about 0.3. However, for CO2 gasification the reaction rate peak was found to be at a conversion degree of about 0.1. Reaction rates have been fitted using the random pore model (RPM). Average structural parameter, ψ for steam gasification and CO2 gasification was determined to be 9 and 2.1, respectively. Average rate constant at 900 oC was 0.065 min-1 for steam gasification and 0.031 min-1 for CO2 gasification. Change in partial pressure of gasifying agents did not affect the reaction rate for both steam and CO2 gasification.

  15. Coal gasification in Europe

    International Nuclear Information System (INIS)

    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

  16. Syngas yield during pyrolysis and steam gasification of paper

    International Nuclear Information System (INIS)

    Main characteristics of gaseous yield from steam gasification have been investigated experimentally. Results of steam gasification have been compared to that of pyrolysis. The temperature range investigated were 600-1000 °C in steps of 100 °C. Results have been obtained under pyrolysis conditions at same temperatures. For steam gasification runs, steam flow rate was kept constant at 8.0 g/min. Investigated characteristics were evolution of syngas flow rate with time, hydrogen flow rate and chemical composition of syngas, energy yield and apparent thermal efficiency. Residuals from both processes were quantified and compared as well. Material destruction, hydrogen yield and energy yield is better with gasification as compared to pyrolysis. This advantage of the gasification process is attributed mainly to char gasification process. Char gasification is found to be more sensitive to the reactor temperature than pyrolysis. Pyrolysis can start at low temperatures of 400 °C; however char gasification starts at 700 °C. A partial overlap between gasification and pyrolysis exists and is presented here. This partial overlap increases with increase in temperature. As an example, at reactor temperature 800 °C this overlap represents around 27% of the char gasification process and almost 95% at reactor temperature 1000 °C.

  17. Experimental studies and CFD simulations of conical spouted bed hydrodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Z.

    2008-07-01

    This thesis involved both experimental research and mathematical modelling of the hydrodynamics of conical spouted beds. Although conical spouted beds are commonly used for drying suspensions, solutions and pasty materials, they can also be used for catalytic partial oxidation of methane to synthesis gas, coal gasification and liquefaction, and pyrolysis of sawdust. Pressure transducers and static pressure probes were used in the experimental studies to investigate the evolution of the internal spout and the local static pressure distribution. Optical fibre probes were used to measure axial particle velocity profiles and voidage profiles. The gas mixing behaviour inside a conical spouted bed was examined using a step trace injection technique in which helium was used as the tracer and thermal conductivity cells were used as the detectors. For the mathematical modelling, a stream-tube model based on the bed structure inside a conical spouted bed was proposed to simulate partial spouting states. An adjustable parameter was introduced into the model to enable total pressure drop prediction under different operating conditions, and to estimate axial superficial gas velocity profiles and gauge pressure profiles. A mathematical model based on characteristics of conical spouted beds and FLUENT software was also developed and validated using measured experimental data. The proposed CFD model can simulate both stable spouting and partial spouting states, with an adjustable solids-phase source term. The effect of all possible factors on simulation results were investigated, including the fluid inlet profile, solid bulk viscosity, frictional viscosity, restitution coefficient, exchange coefficient, and solid phase source term. In addition to simulating the gas mixing behaviours inside a conical spouted bed, the new CFD model simulated cylindrical packed beds and cylindrical fluidized beds in one code package.

  18. Gasification of secondary fuels in a circulating fluidized bed for energetic use in cement production; Vergasung von Sekundaerbrennstoffen in der zirkulierenden Wirbelschicht zur energetischen Nutzung fuer die Zementherstellung

    Energy Technology Data Exchange (ETDEWEB)

    Albrecht, J.; Gafron, B. [Lurgi Umwelt GmbH, Frankfurt am Main (Germany); Scur, P.; Wirthwein, R. [Ruedersdorfer Zement GmbH (Germany)

    1998-09-01

    Ruedersforf cement factory was commissioned a century ago as one of the first in Germany. After the plant was taken over by Readymix AG, a comprehensive sanitation concept was carried through. The plant has a production capacity of 8000 t/d of cement clinkers which are produced in a new kiln with a capacity of 6000 t/d and two modernized kilns each with a capacity of 1000 t/d. Reduction of energy consumption was the main goal of modernisation, with fuel gas generation in a circulating fluidized bed as a key element. The unit provides 40 % of the energy consumed by the clinker production process and is also used for selective ash production up to 25 t/h. The ash is used as a raw material for cement production. (orig./SR) [Deutsch] Bereits vor 100 Jahren wurde eine der ersten Zementfabriken in Deutschland am Standort Ruedersdorf in Betrieb genommen. Zum Erhalt der Wettbewerbsfaehigkeit wurde nach der Uebernahme des Werkes Ruedersdorf durch die Readymix AG ein umfangreiches Sanierungskonzept in die Wege geleitet. Bei einer Produktionskapazitaet von ca. 8 000 t Klinker pro Tag werden eine neue Ofenanlage mit einer Kapazitaet von 6 000 t/Tag sowie 2 sanierte kleine Anlagen zu je 1000 t/Tag betrieben. In der neuen Ofenanlage werden alle Moeglichkeiten genutzt, den Energiebedarf fuer die Klinkerproduktion zu senken. Eine wesentliche neue innovative Komponente ist dabei eine Brenngaserzeugung in einer Zirkulierenden Wirbelschicht, ueber die im folgenden berichtet werden soll. Die Anlage kann bis zu 40% des Energiebedarfes des Zementprozesses liefern. Weiterhin wird mit der ZWS eine gezielte Ascheproduktion, bis zu 25 t/h, betrieben. Diese Aschen sind Teil der Rohstoffrezeptur an der Rohmuehle. (orig./SR)

  19. Investigation of Gas Solid Fluidized Bed Dynamics with Non-Spherical Particles

    Energy Technology Data Exchange (ETDEWEB)

    Choudhuri, Ahsan

    2013-06-30

    One of the largest challenges for 21st century is to fulfill global energy demand while also reducing detrimental impacts of energy generation and use on the environment. Gasification is a promising technology to meet the requirement of reduced emissions without compromising performance. Coal gasification is not an incinerating process; rather than burning coal completely a partial combustion takes place in the presence of steam and limited amounts of oxygen. In this controlled environment, a chemical reaction takes place to produce a mixture of clean synthetic gas. Gas-solid fluidized bed is one such type of gasification technology. During gasification, the mixing behavior of solid (coal) and gas and their flow patterns can be very complicated to understand. Many attempts have taken place in laboratory scale to understand bed hydrodynamics with spherical particles though in actual applications with coal, the particles are non-spherical. This issue drove the documented attempt presented here to investigate fluidized bed behavior using different ranges of non-spherical particles, as well as spherical. For this investigation, various parameters are controlled that included particle size, bed height, bed diameter and particle shape. Particles ranged from 355 µm to 1180 µm, bed diameter varied from 2 cm to 7 cm, two fluidized beds with diameters of 3.4 cm and 12.4 cm, for the spherical and non-spherical shaped particles that were taken into consideration. Pressure drop was measured with increasing superficial gas velocity. The velocity required in order to start to fluidize the particle is called the minimum fluidization velocity, which is one of the most important parameters to design and optimize within a gas-solid fluidized bed. This minimum fluidization velocity was monitored during investigation while observing variables factors and their effect on this velocity. From our investigation, it has been found that minimum fluidization velocity is independent of bed

  20. Gas Cleaning in Gasification: Particle Removal

    Czech Academy of Sciences Publication Activity Database

    Svoboda, Karel; Pohořelý, Michael; Šyc, Michal; Jeremiáš, Michal; Tošnarová, Markéta

    Madrid: CIEMAT, 2012, s. 1-5. [International Summer Schoolon Advanced Concepts and Process Schemes for CO2-Free Fluidized and Entrained Bed Co-Gasification of Coal , Biomass and Waste . Madrid (ES), 03.07.2012-06.07.2012] R&D Projects: GA TA ČR TA01020366; GA MŠk(CZ) 7C11009 Grant ostatní: RFCR(XE) CT-2010-00009 Institutional support: RVO:67985858 Keywords : gasification * cleaning * dust Subject RIV: JE - Non-nuclear Energetics, Energy Consumption ; Use

  1. Gasification development - BHEL`s experience

    Energy Technology Data Exchange (ETDEWEB)

    Basu, K.; Ramani, N.V.S. [Bharat Heavy Electricals Limited, Hyderabad (India)

    1997-12-31

    Bharat Heavy Electricals Limited (BREL) has been engaged in the development of the pressurized fluidized bed combustion and gasification processes for over a decade. Selection and development of gasification processes in BHEL was an integral and complementary part of the development of Integrated Gasification Combined Cycle (IGCC) technology. So far two types namely pressurized moving bed and bubbling fluidized bed gasifier, have been extensively tested for performance independently and also in 6.2 MW IGCC plant developed in-house. Moving bed gasifier performance was also evaluated in a similar gasifier available at IICT. Three fluidized bed gasifier configurations have so far been developed. The basic configuration consists of a two diameter reactor with dry ash removal system. Based on this configuration, initially a 18 tpd PFBG pilot plant had been developed and tested. Recycling of fines from cyclone to gasifier was carried out in the 18 tpd PFBG pilot plant using various types of ejector systems. This configuration was scaled up to a 150 tpd PFBG plant to retrofit in the existing 6.2 MW IGCC plant at BHEL, Trichy. The plant is undergoing initial performance testing. To improve upon the performance, particularly carbon conversion, BHEL has subsequently developed two pilot scale rigs to study ash agglomeration of Indian coals and lignite and a coupled gasifier, where a pressurised fluidized bed combustor operates in tandem with the gasifier. Fines recycle by gravity as well as using L-valve have also been studied in smaller test rigs. A mix of experimental work and mathematical modelling is essential to develop a commercial size gasification reactor. 3 figs., 3 tabs.

  2. Method and apparatus for a combination moving bed thermal treatment reactor and moving bed filter

    Science.gov (United States)

    Badger, Phillip C.; Dunn, Jr., Kenneth J.

    2015-09-01

    A moving bed gasification/thermal treatment reactor includes a geometry in which moving bed reactor particles serve as both a moving bed filter and a heat carrier to provide thermal energy for thermal treatment reactions, such that the moving bed filter and the heat carrier are one and the same to remove solid particulates or droplets generated by thermal treatment processes or injected into the moving bed filter from other sources.

  3. CATALYTIC GASIFICATION OF COAL USING EUTECTIC SALT MIXTURES; FINAL

    International Nuclear Information System (INIS)

    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

  4. The technical and economic feasibility of Cynara cardunculus L. gasification

    OpenAIRE

    Gómez García, Alberto

    2012-01-01

    This PhD Thesis analyses the technical and economic feasibility of the gasification of one of the most promising energy crops in terms of biomass yield and plantation costs: Cynara cardunculus L. (cynara). The aim of this analysis is to assess the bioenergy production via fluidized bed gasification (FBG) and the ulterior treatment of the synthesis gas (syngas) produced in the FBG reactor to adequate it to end-use applications such as gas turbines and internal combustion engines. To achieve th...

  5. Gasification for power, CHP and polygeneration Biomass Gasification for Combined Heat Power (CHP) Applications: the GAMECO Project

    OpenAIRE

    Authier, O; Khalfi, Az-Eddine; Sanchez, L.; Aleman, Y; Delebarre, A; Mauviel, G; Dufour, A; Rogaume, Y; Poirier, J.; Kerhoas, J

    2014-01-01

    International audience Air-blown fluidised bed biomass gasification is a well adapted technology for Combined Heat Power (CHP) applications with syngas valorisation in a gas engine. However, it is not mature yet. Despite promising prototypes, CHP gasification needs further improvements to become the reference technology in the medium-size CHP market. This is the purpose of the GAMECO project, which aims at improving an existing technology by optimising its operation, increasing its feedsto...

  6. International Seminar on Gasification 2008

    Energy Technology Data Exchange (ETDEWEB)

    Held, Joergen (ed.)

    2008-11-15

    results in a product gas free of nitrogen and hence suitable for production of biomethane. The concept has been proven at the Guessing plant using a slip-stream but still we are awaiting the first commercial plant that produce biomethane suitable as vehicle fuel or for grid injection. Several demonstration projects are related to air-blown gasification and CHP production. The two-stage Viking gasifier developed at Technical University of Denmark produces a gas with low tar content (<5 mg/Nm3) suitable for combined heat and power production where a gas engine is used for the electricity production. The 70 kW{sub th} pilot plant has an electric efficiency of 25 %. With a scale-up to 0.2-2 MW{sub e} and improved internal heat recovery an electric efficiency of >37 % is expected. In Skive, Denmark, biomass gasification in a 20 MW{sub th} gasifier based on technology developed at GTI, USA and commercialized by Carbona, Finland is demonstrated. The total investment cost is 30 million Euro. Expected pay-back time is approx. 10 years. The project is delayed and the official opening is planned to April 2009. The delay reflects the inherent uncertainty related to large-scale demonstration of new technology. There are several other demonstrations related to biomass gasification and gas cleaning on their way and the field of gasification seems to experience a renaissance. Gas engines utilizing gasified biomass are commercially available. GE Jenbacher has installed gas engines in many biomass gasification plants in Europe. The accumulated hours of operation for the gas engines well exceed 100,000 hours. The plants with installed gas engines span over different gasification technologies (e.g. fixed bed - updraft, fixed bed - down draft and indirect gasification) and different gas compositions with lower heating values ranging from 5.4 MJ/Nm3 to 10.5 MJ/Nm3. High CO content in the gas results in high CO emissions from the gas engine which calls for exhaust gas after-treatment. To avoid

  7. Pyrolysis and Gasification

    DEFF Research Database (Denmark)

    Astrup, Thomas; Bilitewski, B.

    2011-01-01

    incineration capacity, but also a better ability of gasification over incineration to preserve the chemical energy of the waste is important. This chapter provides an overview of pyrolysis and gasification processes related to waste, the technology involved, energy recovery options, and important environmental......Pyrolysis and gasification include processes that thermally convert carbonaceous materials into products such as gas, char, coke, ash, and tar. Overall, pyrolysis generates products like gas, tar, and char, while gasification converts the carboncontaining materials (e.g. the outputs from pyrolysis......) into a mainly gaseous output. The specific output composition and relative amounts of the outputs greatly depend on the input fuel and the overall process configuration. Although pyrolysis processes in many cases also occur in gasification (however prior to the gasification processes), the overall...

  8. On the gasification of biomass in a steam-oxygen blown CFB gasifier with the focus on gas quality upgrading: technology background, experiments and mathematical modeling

    NARCIS (Netherlands)

    Siedlecki, M.

    2011-01-01

    This work presents and discusses the results of the research on the gasification of biomass in an atmospheric circulating fluidized bed, with a mixture of steam and oxygen as fluidization / gasification medium. The main objectives of this research were to investigate and improve the gasification pro

  9. International Seminar on Gasification 2008

    Energy Technology Data Exchange (ETDEWEB)

    Held, Joergen (ed.)

    2008-11-15

    results in a product gas free of nitrogen and hence suitable for production of biomethane. The concept has been proven at the Guessing plant using a slip-stream but still we are awaiting the first commercial plant that produce biomethane suitable as vehicle fuel or for grid injection. Several demonstration projects are related to air-blown gasification and CHP production. The two-stage Viking gasifier developed at Technical University of Denmark produces a gas with low tar content (<5 mg/Nm3) suitable for combined heat and power production where a gas engine is used for the electricity production. The 70 kW{sub th} pilot plant has an electric efficiency of 25 %. With a scale-up to 0.2-2 MW{sub e} and improved internal heat recovery an electric efficiency of >37 % is expected. In Skive, Denmark, biomass gasification in a 20 MW{sub th} gasifier based on technology developed at GTI, USA and commercialized by Carbona, Finland is demonstrated. The total investment cost is 30 million Euro. Expected pay-back time is approx. 10 years. The project is delayed and the official opening is planned to April 2009. The delay reflects the inherent uncertainty related to large-scale demonstration of new technology. There are several other demonstrations related to biomass gasification and gas cleaning on their way and the field of gasification seems to experience a renaissance. Gas engines utilizing gasified biomass are commercially available. GE Jenbacher has installed gas engines in many biomass gasification plants in Europe. The accumulated hours of operation for the gas engines well exceed 100,000 hours. The plants with installed gas engines span over different gasification technologies (e.g. fixed bed - updraft, fixed bed - down draft and indirect gasification) and different gas compositions with lower heating values ranging from 5.4 MJ/Nm3 to 10.5 MJ/Nm3. High CO content in the gas results in high CO emissions from the gas engine which calls for exhaust gas after-treatment. To avoid

  10. Solar coal gasification

    Science.gov (United States)

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

    1980-01-01

    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.

  11. Radiative Gasification Apparatus

    Data.gov (United States)

    Federal Laboratory Consortium — This apparatus, developed at EL, determines gasification rate (mass loss rate) of a horizontally oriented specimen exposed in a nitrogen environment to a controlled...

  12. Gasification-based biomass

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2009-01-18

    The gasification-based biomass section of the Renewable Energy Technology Characterizations describes the technical and economic status of this emerging renewable energy option for electricity supply.

  13. Sewage Sludge Gasification for CHP Applications

    Energy Technology Data Exchange (ETDEWEB)

    McCahey, S.; Huang, Y.; McMullan, J.T.

    2003-07-01

    Many routes previously available for sewage sludge disposal within the European Union are now prohibited or constrained by environmental legislation. Meanwhile, sewage sludge production increases annually as more rigorous treatment processes are used. This paper introduces an ongoing project, supported by the European Commission FP5 Programme, which seeks to examine the key technical environmental and economic issues relating to the gasification of sewage sludge for utilisation in CHP applications and ultimately to establish the commercial viability of the process. Sewage sludge treatment data has been collected by country and region and a database compiled. Laboratory and pilot plant scale gasification trials are underway and two small engines and a generator have been installed and commissioned. This paper discusses the concurrent development of ECLIPSE process simulation models for the three selected gasification processes, namely fluidised bed, spouted bed and fixed bed. These models have been validated and are being used to predict the behaviour of appropriately sized commercial scale plant, enabling informed decisions regarding technical suitability. The next step in this project is to determine capital costs and economic performance. Process routes will be identified that offer the most cost effective routes to reducing environmental burdens by using sewage sludge in CHP applications. (author)

  14. Innovative gasification technology for future power generation

    Energy Technology Data Exchange (ETDEWEB)

    Mahajan, K.; Shadle, L.J. [Dept. of Energy, Morgantown, WV (United States); Sadowski, R.S. [Jacobs-Sirrine Engineers, Inc., Greenville, SC (United States)

    1995-07-01

    Ever tightening environmental regulations have changed the way utility and non-utility electric generation providers currently view their fuels choices. While coal is still, by far, the major fuel utilized in power production, the general trend over the past 20 years has been to switch to low-sulfur coal and/or make costly modifications to existing coal-fired facilities to reach environmental compliance. Unfortunately, this approach has led to fragmented solutions to balance our energy and environmental needs. To date, few integrated gasification combined-cycle (IGCC) suppliers have been able to compete with the cost of other more conventional technologies or fuels. One need only look at the complexity of many IGCC approaches to understand that unless a view toward IEC is adopted, the widespread application of such otherwise potentially attractive technologies will be unlikely in our lifetime. Jacobs-Sirrine Engineers and Riley Stoker Corporation are working in partnership with the Department of Energy`s Morgantown Energy Technology Center to help demonstrate an innovative coal gasification technology called {open_quotes}PyGas{trademark},{close_quotes} for {open_quotes}pyrolysis-gasification{close_quotes}. This hybrid variation of fluidized-bed and fixed-bed gasification technologies is being developed with the goal to efficiently produce clean gas at costs competitive with more conventional systems by incorporating many of the principles of IEC within the confines of a single-gasifier vessel. Our project is currently in the detailed design stage of a 4 ton-per-hour gasification facility to be built at the Fort Martin Station of Allegheny Power Services. By locating the test facility at an existing coal-fired plant, much of the facility infrastructure can be utilized saving significant costs. Successful demonstration of this technology at this new facility is a prerequisite to its commercialization.

  15. The formation of ammonia in air-blown gasification: does char-derived NO act as a precursor?

    Energy Technology Data Exchange (ETDEWEB)

    O. Amure; S. Hanson; M. Cloke; J.W. Patrick [University of Nottingham, Nottingham (United Kingdom). SChEME

    2003-10-01

    Air-blown gasification of coal has received considerable attention worldwide and especially in the UK in conjunction with the Air-Blown Gasification Cycle, an integrated combined cycle which has been developed in recent decades. The cycle has the potential to produce electricity at higher efficiencies and lower emissions than conventional pf plants. However, the formation of ammonia in the gasifier has been identified as a potential problem, as it would contribute to NOx emissions. The formation of ammonia has been studied in a laboratory-scale rig designed and constructed specifically for that purpose. The reactor was a fluidised bed of the spouted bed variety. NH{sub 3}, NO and HCN levels could be monitored at different bed heights to trace their formation and conversion. Four coals were gasified at 1000{sup o}C and 0.2 MPa. It was found that the bulk of the NH{sub 3} was formed in the spout and the NH{sub 3} concentration increased progressively with reactor height. Formation of NO was relatively minor and, although both NO and HCN may act as precursors for NH{sub 3} formation in the devolatilisation/partial combustion zone, no evidence was found to suggest they make a significant contribution to any subsequent increase in NH{sub 3} emissions. 12 refs., 4 figs., 2 tabs.

  16. Integrated hot fuel gas cleaning for advanced gasification combined cycle process

    Energy Technology Data Exchange (ETDEWEB)

    Nieminen, M.; Kangasmaa, K.; Laatikainen, J.; Staahlberg, P.; Kurkela, E. [VTT Energy, Espoo (Finland). Gasification and Advanced Combustion

    1996-12-01

    The fate of halogens in pressurised fluidized-bed gasification and hot gas filtration is determined. Potential halogen removal sorbents, suitable for integrated hot gas cleaning, are screened and some selected sorbents are tested in bench scale. Finally, halogen removal results are verified using the PDU-scale pressurised fluidized-bed gasification and integrated hot gas cleaning facilities of VTT. The project is part of the JOULE II Extension programme of the European Union. (author)

  17. Coal gasification and the power production market

    International Nuclear Information System (INIS)

    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

  18. Gasification biochar as a valuable by-product for carbon sequestration and soil amendment

    DEFF Research Database (Denmark)

    Hansen, Veronika; Müller-Stöver, Dorette Sophie; Ahrenfeldt, Jesper;

    2015-01-01

    Thermal gasification of various biomass residues is a promising technology for combining bioenergy production with soil fertility management through the application of the resulting biochar as soil amendment. In this study, we investigated gasification biochar (GB) materials originating from two...... major global biomass fuels: straw gasification biochar (SGB) and wood gasification biochar (WGB), produced by a Low Temperature Circulating Fluidized Bed gasifier (LT-CFB) and a TwoStage gasifier, respectively, optimized for energy conversion. Stability of carbon in GB against microbial degradation was...

  19. Substitute natural gas from biomass gasification

    Energy Technology Data Exchange (ETDEWEB)

    Tunaa, Per (Lund Inst. of Technology, Lund (SE))

    2008-03-15

    Biomass is by many considered as the only alternative to phase-out the usage of fossil fuels such as natural gas and oil especially for the transportation sector where alternative solutions, such as hydrogen fuel cells and batteries, are not yet fully developed. Thermal gasification or other methods such as pyrolysis of the biomass must be applied in order to produce an intermediate product suitable for further upgrading to either gaseous or liquid products. This thesis will evaluate the possibilities of producing, substitute natural gas, (SNG) from biomass gasification by using computer simulation. Three different gasification techniques were evaluated; entrained-flow, fluidized-bed and indirect gasification coupled with two different desulphurisation systems and two methanation processes. The desulphurisation systems were a zinc oxide bed and a Rectisol wash system. Methanation were performed by a series of adiabatic reactors with gas recycling and by an isothermal reactor. The impact on SNG efficiency from system pressure, isothermal methanation temperature and PSA methane recovery were evaluated as well. The results show that the fluidized-bed and the indirect gasifier have the highest SNG efficiency. Furthermore there are little to no difference between the methanation processes and small differences for the gas cleanup systems. SNG efficiencies in excess of 50 % were possible for all gasifiers. SNG efficiency is defined as the energy in the SNG product divided by the total input to the system from biomass, drying and oxygen. Increasing system pressure has a negative impact on SNG efficiency as well as increasing operating costs due to increased power for compression. Isothermal methanation temperature has no significant impact on SNG efficiency. Recovering as much methane as possible in the PSA is the most important parameter. Recovering methane that has been dissolved in condensed process water increases the SNG efficiency by 2-10% depending on system.

  20. Removal of ammonia from producer gas in biomass gasification: integration of gasification optimisation and hot catalytic gas cleaning

    Energy Technology Data Exchange (ETDEWEB)

    Hongrapipat, Janjira; Saw, Woei-Lean; Pang, Shusheng [University of Canterbury, Department of Chemical and Process Engineering, Christchurch (New Zealand)

    2012-12-15

    Ammonia (NH{sub 3}) is one of the main contaminants in the biomass gasification producer gas, which is undesirable in downstream applications, and thus must be removed. When the producer gas is used in integrated gasification combined cycle (IGCC) technology, NH{sub 3} is the main precursor of nitrogen oxides (NO{sub x}) formed in gas turbine, whereas in Fischer-Tropsch synthesis and in integrated gasification fuel cell (IGFC) technology, the NH{sub 3} gas poisons the catalysts employed. This paper presents a critical review on the recent development in the understanding of the NH{sub 3} formation in biomass gasification process and in the NH{sub 3} gas cleaning technologies. The NH{sub 3} gas concentration in the producer gas can firstly be reduced by the primary measures taken in the gasification process by operation optimisation and using in-bed catalytic materials. Further removal of the NH{sub 3} gas can be implemented by the secondary measures introduced in the post-gasification gas-cleaning process. Focus is given on the catalytic gas cleaning in the secondary measures and its advantages are analysed including energy efficiency, impacts on environment and recyclability of the catalyst. Based on the review, the most effective cleaning process is proposed with integration of both the primary and the secondary measures for application in a biomass gasification process. (orig.)

  1. Pyrolysis and Gasification

    DEFF Research Database (Denmark)

    Astrup, Thomas; Bilitewski, B.

    2011-01-01

    Pyrolysis and gasification include processes that thermally convert carbonaceous materials into products such as gas, char, coke, ash, and tar. Overall, pyrolysis generates products like gas, tar, and char, while gasification converts the carboncontaining materials (e.g. the outputs from pyrolysis....... In Europe during World War II, wood-fueled gasifiers (or ‘gas generators’) were used to power cars during shortages of oil-based fuels. Sparked by oil price crises in 1970s and 1980s, further development in gasification technologies focused mainly on coal as a fuel to substitute for oil...

  2. Bed agglomeration risk related to combustion of cultivated fuels (wheat straw, red canary grass, industrial hemp) in commercial bed materials; Baeddagglomereringsrisk vid foerbraenning av odlade braenslen (hampa, roerflen, halm) i kommersiella baeddmaterial

    Energy Technology Data Exchange (ETDEWEB)

    Erhardsson, Thomas; Oehman, Marcus; Geyter, Sigrid de; Oehrstroem, Anna

    2006-12-15

    The market of forest products is expanding and thus resulting in more expensive biomass fuels. Therefore research within the combustion industry for alternative fuels is needed, for example cultivated fuels. Combustion and gasification research on these cultivated fuels are limited. The objectives of this work was to increase the general knowledge of silicon rich cultivated fuels by study the agglomeration characteristics for wheat straw, reed canary grass and industrial hemp in combination with commercial bed materials. Controlled fluidized bed agglomeration tests was conducted in a 5 kW, bench-scale, bubbling fluidized bed reactor. The tendencies of agglomeration were determined with the three cultivated fuels in combination with various minerals present in natural sand (quarts, plagioclase and potassium feldspar) and an alternative bed material (olivine). During the experiments bed samples and formed agglomerates were collected for further analyses with a scanning electron microscope (SEM) and with X-ray microanalysis (EDS). Wheat straw had the highest agglomeration tendency of the studied fuels followed by reed canary grass and industrial hemp. No significant layer formation was found around the different bed particles. Instead, the ash forming matter were found as individual ash sticky (partial melted) particles in the bed. The bed material mineralogical composition had no influence of the agglomeration process because of the non layer formation propensities of the used silicon rich fuels.

  3. Gasification to petrochemicals

    International Nuclear Information System (INIS)

    Gasification is often used to convert coal, petroleum coke and heavy hydrocarbons to gaseous products for hydrogenation in oil refining and upgrading. Gasification produces a variety of byproducts that can be used to produce petrochemicals. Primary petrochemical derivatives from sulfur, nitrogen, and oxygen can enhance the overall economics of the gasification process, and gasification by-products can be combined with other hydrocarbon feedstocks to produce a variety of secondary and tertiary petrochemical products. This presentation examined the potential for primary, secondary and tertiary petrochemicals derived from Alberta's oil sands industry. The gasification units associated with oil sands processing plants are the largest in the world, which suggests that syngas and other gasification products will benefit from economies of scale. A proposed flow scheme for oil sands bitumen using a naphtha cracker to create ethylene and other petrochemicals was presented as well as flow schemes for the creation of light hydrocarbons, syngas and aromatics. Ammonia and methanol synthesis processes from natural gas were reviewed, as well as issues concerning acetic acid synthesis and phenol synthesis from benzene and propylene. It was concluded that all the products and feedstocks reviewed in the analysis are readily transported and have established markets. refs., tabs., figs

  4. Gasification - Status and technology

    Energy Technology Data Exchange (ETDEWEB)

    Held, Joergen

    2012-06-15

    In this report gasification and gas cleaning techniques for biomass are treated. The main reason for gasifying biomass is to refine the fuel to make it suitable for efficient CHP production, as vehicle fuel or in industrial processes. The focus is on production of synthesis gas that can be used for production of vehicle fuel and for CHP production. Depending on application different types of gasifiers, gasification techniques and process parameters are of interest. Two gasification techniques have been identified as suitable for syngas generation, mainly due to the fact that they allow the production of a nitrogen free gas out of the gasifier; Indirect gasification and pressurized oxygen-blown gasification For CHP production there are no restrictions on the gas composition in terms of nitrogen and here air-blown gasification is of interest as well. The main challenge when it comes to gas cleaning is related to sulphur and tars. There are different concepts and alternatives to handle sulphur and tars. Some of them are based on conventional techniques with well-proven components that are commercially available while others, more advantageous solutions, still need further development.

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

    Energy Technology Data Exchange (ETDEWEB)

    Kevin Whitty

    2003-12-01

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

  6. 循环流化床锅炉掺烧气化渣和煤泥的可行性研究%Feasibility Study of Circulating Fluidized Bed Boiler Blending Burning Gasification Slag and Coal Slime

    Institute of Scientific and Technical Information of China (English)

    晁岳建; 王洪记

    2015-01-01

    在分析并借鉴气化渣、煤泥利用探索经验基础上,研究分析了气化渣的理化特性及入炉燃烧的可行性。通过流变性试验,确定了气化渣与煤泥以质量比1∶1(含水质量分数30%±2%)混合成浆后通过煤泥泵进行输送。气化渣、煤泥与原煤掺烧的综合发热量可满足锅炉设计的燃料要求,对锅炉效率及其安全稳定运行基本没有影响,可实现煤炭资源的综合利用。该项目实施后,不到2年即可收回投资,经济效益显著。%Based on analysis and using the experience of utilization investigation of gasification slag and coal slime for reference,the physical and chemical characteristics of gasification slag and feasibility of burning by boiler are studied and analyzed.By rheological behavior experiment,it is determined that gasification slag and coal slime are mixed by mass ratio 1 ∶1 (mass fraction of water holding 30% ±2%)into slurry and then transported by coal slime pump.The synthetic calorific value of blending burning of gasification slag,coal slime and raw coal can meet the requirement for fuel of boiler design,has basically no effect on boiler efficiency,safe and stable operation,being able to realize comprehensive utilization of coal resources.After implementation of the project,the investment can be recouped in less than 2 years,having remarkable economic benefit.

  7. Gasification from waste organic materials

    Directory of Open Access Journals (Sweden)

    Santiago Ramírez Rubio

    2011-08-01

    Full Text Available This article describes the fixed bed biomass gasifier operation designed and built by the Clean Development Mechanisms and Energy Management research group, the gasifier equipment and the measurement system. The experiment involved agro-industrial residues (biomass such wood chips, coconut shell, cocoa and coffee husk; some temperatures along the bed, its pressure, inlet air flow and the percentage of carbon monoxide and carbon dioxide in the syngas composition were measured. The test results showed that a fuel gas was being obtained which was suitable for use with an internal combustion engine for generating electricity because more carbon monoxide than carbon dioxide was being obtained during several parts of the operation. The gasification experimentation revealed that a gasifier having these characteristics should be ideal for bringing energy to areas where it is hard to obtain it (such as many rural sites in Latin-America or other places where large amounts of agro-industrial wastes are produced. Temperatures of around 1,000°C were obtained in the combustion zone, generating a syngas having more than 20% carbon monoxide in its composition, thereby leading to obtaining combustible gas.

  8. Catalytic Partial Oxidation of Methane with Air to Syngas in a Pilot-Plant-Scale Spouted Bed Reactor%甲烷空气部分氧化制合成气喷动床反应器的研究

    Institute of Scientific and Technical Information of China (English)

    魏伟胜; 徐建; 方大伟; 鲍晓军

    2003-01-01

    On the basis of hydrodynamic and scaling-up studies, a pilot-plant-scale thermal spouted bed reactor (50 mm in ID and 1500 mm in height) was designed and fabricated by scaling-down cold simulators. It was tested for making syngas via catalytic partial oxidation (CPO) of methane by air. The effects of various operating conditions such as operating pressure and temperature, feed composition, and gas fiowrate etc. on the CPO process were investigated. CH4 conversion of 92.2% and selectivity of 92.3% and 83.3% to CO and H2, respectively, were achieved at the pressure of 2.1 MPa. It was found that when the spouted bed reactor was operated within the stable spouting flow regime, the temperature profiles along the bed axis were much more uniform than those operated within the fixed-bed regime. The CH4 conversion and syngas selectivity were found to be close to thermodynamic equilibrium limits. The results of the present investigation showed that spouted bed could be considered as a potential type of chemical reactor for the CPO process of methane.

  9. Study on pyrolysis and gasification of wood in MSW

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In order to develop municipal solid waste(MSW) pyrolysis/gasification and melting technology with low emission and high efficiency, it was planed that all the main components in MSW and some typical kinds of MSW were pyrolyzed/gasified to propose an expert system for raw MSW. In this paper, wood, which was a prevalent component in MSW, was pyrolyzed and gasified in fluidized-bed reactors at different apparent excess air ratios (EARs), temperatures and fluidizing velocities. For pyrolysis, with temperature increasing from 400℃ to 700℃, the yield of pyrolysis char decreased while that of pyrolysis gas increased (in this paper respectively from 28% to 20% and from 10% to 35%), and when temperature was 500℃, the yield of pyrolysis tar reached the highest,up to 38% in this paper. It was the optimum for gasification when temperature was 600℃ and apparent EAR was 0.4. Under the experimental conditions of this paper, gasification efficiency achieved 73%, lower heat value(LHV) reached 5800 kJ/(Nm3) and yield of syngas was 2.01 Nm3/kg. Lower fluidizing velocity was useful to upgrade gasification efficiency and LHV of syngas for wood gasification. Based on the results, the reactive courses and mechanism were analyzed respectively for wood pyrolysis and gasification.

  10. Steam gasification of wheat straw, barley straw, willow and giganteus

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, L.K. [FLS Miljoe A/S, Valby (Denmark); Rathmann, O.; Olsen, A. [Risoe National Lab., Roskilde (Denmark); Poulsen, K. [ReaTech, CAT Science Centre Roskilde (Denmark)

    1997-08-01

    A thorough experimental study of the H{sub 2}O gasification char-reactivity of wheat straw, barley straw, willow and giganteus at 1-10 bar total pressure, 0.15-1.5 bar H{sub 2}O and O-1.0 bar H{sub 2} and 750-925 C, was performed in a Pressurized Thermogravimetric Analyzer. There were a total of 58 experiments. Kinetic experiments with char of wheat straw at 10 bar total pressure showed that the reactivity increases with rising temperature and increasing partial pressure of H{sub 2}O,, while it decreases with increasing partial pressure of H{sub 2}. At constant partial H{sub 2}O pressure in the absence of H-2, an indication of a negative influence by the total pressure was observed. Except for the effect of total pressure, the experimental data were analyzed by means of the Langmuir-Hinshelwood equation, including both inhibition by H{sub 2} and reactivity limitation at high H{sub 2}O concentration. Also, the reactivity profile was assumed to be independent of temperature and reactant concentration. The value found for the main activation energy E{sub 1}, 149 kJ/mole, describing the temperature dependence at low H{sub 2}O concentration, is close to experimental values for biomass reported by other workers. At conditions relevant to both fluid-bed and entrained-flow gasifier types the present results indicate an inhibiting effect of the product gas H{sub 2}, reducing the reactivity by a factor of up to 10. A screening study of steam gasification of barley straw, willow and giganteus in addition to the wheat straw showed reaction rates with rather equal temperature dependence. However, at equal temperatures, there was a spread in reactivity of about 10 times from the lowest (wheat and giganteus) to the highest (barley), probably due to different contents of catalytic elements. (au) 5 tabs., 15 ills., 10 refs.

  11. Mathematical Modeling of Ultra-Superheated Steam Gasification

    Science.gov (United States)

    Xin, Fen

    Pure steam gasification has been of interest in hydrogen production, but with the challenge of supplying heat for endothermic reactions. Traditional solutions included either combusting feedstocks at the price of decreasing carbon conversion ratio, or using costly heating apparatus. Therefore, a distributed gasifier with an Ultra-Superheated-Steam (USS) generator was invented, satisfying the heat requirement and avoiding carbon combustion in steam gasification. This project developed the first version of the Ultra-Superheated-Steam-Fluidization-Model (USSFM V1.0) for the USS gasifier. A stand-alone equilibrium combustion model was firstly developed to calculate the USS mixture, which was the input to the USSFM V1.0. Model development of the USSFM V1.0 included assumptions, governing equations, boundary conditions, supporting equations and iterative schemes of guessed values. There were three nested loops in the dense bed and one loop in the freeboard. The USSFM V1.0 included one main routine and twenty-four subroutines. The USSFM V1.0 was validated with experimental data from the Enercon USS gasifier. The calculated USS mixture had a trace of oxygen, validating the initial expectation of creating an oxygen-free environment in the gasifier. Simulations showed that the USS mixture could satisfy the gasification heat requirement without partial carbon combustion. The USSFM V1.0 had good predictions on the H2% in all tests, and on other variables at a level of the lower oxygen feed. Provided with higher oxygen feed, the USSFM V1.0 simulated hotter temperatures, higher CO% and lower CO2%. Errors were explained by assumptions of equilibrium combustion, adiabatic reactors, reaction kinetics, etc. By investigating specific modeling data, gas-particle convective heat transfers were found to be critical in energy balance equations of both emulsion gas and particles, while bubble size controlled both the mass and energy balance equations of bubble gas. Parametric study

  12. Gasification Plant Cost and Performance Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Samuel Tam; Alan Nizamoff; Sheldon Kramer; Scott Olson; Francis Lau; Mike Roberts; David Stopek; Robert Zabransky; Jeffrey Hoffmann; Erik Shuster; Nelson Zhan

    2005-05-01

    As part of an ongoing effort of the U.S. Department of Energy (DOE) to investigate the feasibility of gasification on a broader level, Nexant, Inc. was contracted to perform a comprehensive study to provide a set of gasification alternatives for consideration by the DOE. Nexant completed the first two tasks (Tasks 1 and 2) of the ''Gasification Plant Cost and Performance Optimization Study'' for the DOE's National Energy Technology Laboratory (NETL) in 2003. These tasks evaluated the use of the E-GAS{trademark} gasification technology (now owned by ConocoPhillips) for the production of power either alone or with polygeneration of industrial grade steam, fuel gas, hydrocarbon liquids, or hydrogen. NETL expanded this effort in Task 3 to evaluate Gas Technology Institute's (GTI) fluidized bed U-GAS{reg_sign} gasifier. The Task 3 study had three main objectives. The first was to examine the application of the gasifier at an industrial application in upstate New York using a Southeastern Ohio coal. The second was to investigate the GTI gasifier in a stand-alone lignite-fueled IGCC power plant application, sited in North Dakota. The final goal was to train NETL personnel in the methods of process design and systems analysis. These objectives were divided into five subtasks. Subtasks 3.2 through 3.4 covered the technical analyses for the different design cases. Subtask 3.1 covered management activities, and Subtask 3.5 covered reporting. Conceptual designs were developed for several coal gasification facilities based on the fluidized bed U-GAS{reg_sign} gasifier. Subtask 3.2 developed two base case designs for industrial combined heat and power facilities using Southeastern Ohio coal that will be located at an upstate New York location. One base case design used an air-blown gasifier, and the other used an oxygen-blown gasifier in order to evaluate their relative economics. Subtask 3.3 developed an advanced design for an air

  13. Experimental study on MSW gasification and melting technology

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In order to develop municipal solid waste (MSW) gasification and melting technology, two preliminary experiments and a principle integrated experiment were fulfilled respectively. The gasification characteristics of MSW are studied at 500-750℃ when equivalence ratio (ER) was 0.2-0.5 using a fluidized-bed gasifier. When temperature was 550-700℃ and ER was 0.2-0.4, low heat value (LHV) of syngas reaches 4000-12000 kJ/Nm3. The melting characteristics of fly ash were investigated at 1100-1460℃ using a fixed-bed furnace. It was proved that over 99.9% of dioxins could be decomposed and most heavy-metals could be solidified when temperature was 1100-1300℃. The principle integrated experiment was carried out in a fluidized-bed gasification and swirl-melting system. MSW was gasified efficiently at 550-650℃, swirl-melting furnace maintains at 1200-1300℃ stably and over 95% of fly ash could be caught by the swirl-melting furnace. The results provided much practical experience and basic data to develop MSW gasification and melting technology.

  14. System analysis of dry black liquor gasification based synthetic gas production comparing oxygen and air blown gasification systems

    International Nuclear Information System (INIS)

    Highlights: ► Circulating fluidized bed system for black liquor gasification with direct causticization. ► Effects of gasifying medium i.e. oxygen or air, on gasification are studied. ► Direct causticization eliminates energy intensive limekiln reducing biomass use. ► Results show 10% higher SNG production from O2 blown system than air blown system. ► SNG production is higher in O2 blown system than air blown system. - Abstract: The black liquor gasification based bio-fuel production at chemical pulp mill is an attractive option to replace conventional recovery boilers increasing system energy efficiency. The present paper studies circulating fluidized bed system with direct causticization using TiO2 for the gasification of the black liquor to the synthesis gas. The advantage of using direct causticization is the elimination of energy-intensive lime kiln which is an integral part of the conventional black liquor recovery system. The study evaluates the effects of gasifying medium i.e. oxygen or air, on the fluidized bed gasification system, the synthesis gas composition, and the downstream processes for the synthesis gas conversion to the synthetic natural gas (SNG). The results showed higher synthetic natural gas production potential with about 10% higher energy efficiency using oxygen blown gasification system than the air blown system. From the pulp mill integration perspective, the material and energy balance results in better integration of air blown system than the oxygen blown system, e.g. less steam required to be generated in the power boiler, less electricity import, and less additional biomass requirement. However, the air blown system still requires a significant amount of energy in terms of the synthesis gas handling and gas upgrading using the nitrogen rejection system

  15. Catalytic Gasification of Lignocellulosic Biomass

    NARCIS (Netherlands)

    Chodimella, V.P.; Seshan, K.; Schlaf, Marcel; Zhang, Z. Conrad

    2015-01-01

    Gasification of lignocellulosic biomass has attracted substantial current research interest. Various possible routes to convert biomass to fuels have been explored. In the present chapter, an overview of the gasification processes and their possible products are discussed. Gasification of solid biom

  16. Partial oxidation of Raffinate II and other mixtures of n-Butane and n-Butenes to maleic anhydride in a fixed-bed reactor

    OpenAIRE

    Brandstädter, Willi Michael

    2008-01-01

    The utilisation of the C4 streams of steamcrackers by converting raffinate II to maleic anhydride was studied. The oxidation reactions were investigated in a laboratory-scale fixed-bed reactor to determine reaction kinetics. The effects of pore diffusional resistance were investigated and explained. A two-dimensional pseudo-homogeneous reactor model was used for the simulation of a production-scale fixed-bed reactor. A flow scheme of the reactor section including a recycle was proposed.

  17. Fuel bed evaluations and coal properties transformation in a Sasol-Lurgi fixed bed dry bottom gasifier operating on North Dakota lignite / Setobane Jonas Mangena

    OpenAIRE

    Mangena, Setobane Jonas

    2008-01-01

    The growth in coal consumption worldwide as well as the high oil prices in the recent past has led to the current increased interest in the application of coal gasification technologies. The Sasoi-Lurgi Fixed Bed Dry Bottom (S-L FBDB) gasification technology is one such technology that has the biggest market share in the world and maintains its competitive edge particularly with regard to gasification of low grade and low rank coal. To ensure sustained competitive advantage through tech...

  18. Fuel gas from biomass for power and heat generation. Results of tests at the test gasification plant at Technical University Dresden; Brenngase aus Biomasse fuer die Strom- und Waermeerzeugung. Ergebnisse der Untersuchungen am Vergasungsversuchsstand der TU Dresden

    Energy Technology Data Exchange (ETDEWEB)

    Boehning, D.; Beckmann, M. [Technische Universitaet Dresden (Germany). Institut fuer Energietechnik

    2009-07-01

    The gasification of biomass into smaller decentralized plants with a thermal output up to 500 kW has been a subject of variable intensity in research and development. The current development state of the process is however still insufficient regardless of the process, such that a reliable and economic operation of the plants can be guaranteed. For the use of the produced fuel in the gas-engine, high standards are necessary for its quality. The article focusses on the reduction of tar content in fuel gas via catalytic partial oxidation. It describes the theoretical analysis of fundamentals with results and presents experimental tests at the gasification plant and the obtained results. Tests have been realized at the 75 kW{sub th} fixed bed gasifier at the catalytic partial oxidation (1{sup st} Function unit) and at the cooling of gas (2{sup nd} Function unit). The construction and material of the catalyst are essential parameters as well as the apply amount of oxygen, the position of supplying and mixing. By the use of a gas cooling in a stationary fluidized bed is it possible to decrease the tar content in the fuel gas, via condensation on bed material (charcoal). The gas cooling is installed behind the catalyst. The outcome of the combination of both gas treatment-function-units is a further monovariant for optimization. The second unit can also be considered as a ''safety filter''. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

    Kevin Whitty

    2007-06-30

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

  20. Gasification-based energy production systems for different size classes - Potential and state of R and D

    International Nuclear Information System (INIS)

    (Conference paper). Different energy production systems based on biomass and waste gasification are being developed in Finland. In 1986-1995 the Finnish gasification research and development activities were almost fully devoted to the development of simplified IGCC power systems suitable to large-scale power production based on pressurized fluid-bed gasification, hot gas cleaning and a combined-cycle process. In the 1990's the atmospheric-pressure gasification activities aiming for small and medium size plants were restarted in Finland. Atmospheric-pressure fixed-bed gasification of wood and peat was commercialized for small-scale district heating applications already in the 1980's. Today research and development in this field aims at developing a combined heat and power plant based on the use of cleaned product gas in internal combustion engines. Another objective is to enlarge the feedstock basis of fixed-bed gasifiers, which at present are limited to the use of piece-shaped fuels such as sod peat and wood chips. Intensive research and development is at present in progress in atmospheric-pressure circulating fluidized-bed gasification of biomass residues and wastes. This gasification technology, earlier commercialized for lime-kiln applications, will lead to co-utilization of local residues and wastes in existing pulverized coal fired boilers. The first demonstration plant is under construction in Finland and there are several projects under planning or design phase in different parts of Europe. 48 refs., 1 fig., 1 tab

  1. Gasification-based energy production systems for different size classes - Potential and state of R and D

    Energy Technology Data Exchange (ETDEWEB)

    Kurkela, E.

    1997-12-31

    (Conference paper). Different energy production systems based on biomass and waste gasification are being developed in Finland. In 1986-1995 the Finnish gasification research and development activities were almost fully devoted to the development of simplified IGCC power systems suitable to large-scale power production based on pressurized fluid-bed gasification, hot gas cleaning and a combined-cycle process. In the 1990`s the atmospheric-pressure gasification activities aiming for small and medium size plants were restarted in Finland. Atmospheric-pressure fixed-bed gasification of wood and peat was commercialized for small-scale district heating applications already in the 1980`s. Today research and development in this field aims at developing a combined heat and power plant based on the use of cleaned product gas in internal combustion engines. Another objective is to enlarge the feedstock basis of fixed-bed gasifiers, which at present are limited to the use of piece-shaped fuels such as sod peat and wood chips. Intensive research and development is at present in progress in atmospheric-pressure circulating fluidized-bed gasification of biomass residues and wastes. This gasification technology, earlier commercialized for lime-kiln applications, will lead to co-utilization of local residues and wastes in existing pulverized coal fired boilers. The first demonstration plant is under construction in Finland and there are several projects under planning or design phase in different parts of Europe. 48 refs., 1 fig., 1 tab.

  2. Catalytic steam gasification of biomass for a sustainable hydrogen future: influence of catalyst composition

    OpenAIRE

    Wu, C.; Wang, Z.; Wang, L.; J. Huang; Williams, PT

    2014-01-01

    Hydrogen is regarded as a clean energy for fuelling the future. Hydrogen will be the energy carrier from other resources such as hydropower, wind, solar and biomass. Producing hydrogen from gasification of biomass wastes, particularly in the presence of steam, represents a promising route to produce this clean and CO2-neutral fuel. The steam pyrolysis-gasification ofbiomass (wood sawdust) was carried out with various nickel-based catalysts for hydrogen production in a two-stage fixed bed reac...

  3. Downdraft gasification of pellets made of wood, palm-oil residues respective bagasse: Experimental study

    International Nuclear Information System (INIS)

    The downdraft gasification technology has an increased interest among researchers worldwide due to the possibility to produce mechanical and electrical power from biomass in small-scale to an affordable price. The research is generally focused on improvement of the performance and optimizing of a certain gasifier, on testing different fuels, on increasing the user-friendliness of the gasifier and on finding other uses for the product gas than in an IC-engine, for example liquid fuel production. The main objective with the gasification tests presented here is to further contribute in the field by studying the impact of the char bed properties such as char bed porosity and pressure drop on the gasification performance as well as the impact of fuel particle size and composition on the gasification process in one and the same gasifier. In addition, there is very little gasification data available in literature of 'before disregarded' fuels such as sugar cane bagasse from sugar/alcohol production and empty fruit bunch (EFB) from the palm-oil production. By pelletizing these residues, it is possible to introduce them into downdraft gasification technology which has been done in this study. The results show that one and the same reactor can be used for a variety of fuels in pellet form, but at varying air-fuel ratios, temperature levels, gas compositions and lower heating values. Gasification of wood pellets results in a richer producer gas while EFB pellets give a poorer one with higher contents of non-combustible compounds. In this gasification study, there is almost linear relation between the air-fuel ratio and the cold-gas efficiency for the studied fuels: Higher air-fuel ratios result in better efficiency. The pressure drop in the char bed is higher for more reactive fuels, which in turn is caused by low porosity char beds.

  4. Downdraft gasification of pellets made of wood, palm-oil residues respective bagasse: Experimental study

    International Nuclear Information System (INIS)

    The downdraft gasification technology has an increased interest among researchers worldwide due to the possibility to produce mechanical and electrical power from biomass in small-scale to an affordable price. The research is generally focused on improvement of the performance and optimizing of a certain gasifier, on testing different fuels, on increasing the user-friendliness of the gasifier and on finding other uses for the product gas than in an IC-engine, for example liquid fuel production. The main objective with the gasification tests presented here is to further contribute in the field by studying the impact of the char bed properties such as char bed porosity and pressure drop on the gasification performance as well as the impact of fuel particle size and composition on the gasification process in one and the same gasifier. In addition, there is very little gasification data available in literature of ''before disregarded'' fuels such as sugar cane bagasse from sugar/alcohol production and empty fruit bunch (EFB) from the palm-oil production. By pelletizing these residues, it is possible to introduce them into downdraft gasification technology which has been done in this study. The results show that one and the same reactor can be used for a variety of fuels in pellet form, but at varying air-fuel ratios, temperature levels, gas compositions and lower heating values. Gasification of wood pellets results in a richer producer gas while EFB pellets give a poorer one with higher contents of non-combustible compounds. In this gasification study, there is almost linear relation between the air-fuel ratio and the cold-gas efficiency for the studied fuels: Higher air-fuel ratios result in better efficiency. The pressure drop in the char bed is higher for more reactive fuels, which in turn is caused by low porosity char beds. (author)

  5. Inventory of future power and heat production technologies. Partial report Gasification with gas turbine/engine for power plants; Incl. English lang. appendix of 24 p. titled 'Status of large-scale biomass gasification for power production'; Inventering av framtidens el och vaermeproduktionstekniker. Delrapport Foergasning med gasturbin/motor foer kraftvaerk

    Energy Technology Data Exchange (ETDEWEB)

    Waldheim, Lars; Larsson, Eva K. (TPS Termiska Processer, Nykoeping (Sweden))

    2008-12-15

    This subproject is limited to applications with gas turbines or engines from approximately 1 MWe and firing of gas in a boiler either as indirect cofiring or as separate firing of gas from waste gasification. Gasification with gas engine, BIG-ICE (Biomass Integrated Gasification Internal-Combustion Engine) is realized in approximately 10 plants in Europe between 1 and 7 MWe. The gas needs to be cleaned from particles and tar before it is fed to the engine. A number of different gasifiers and gas cleaning technologies are applied in these prototypes, and in certain cases a second generation is being built. Gas engines from GE Jenbacher are most common, but there are also other producers with engines for low-calorific-value gas. The exhausts from engines must, unlike gas turbines, be cleaned catalytically, but emissions of hydrocarbons in particular are still higher than from gas turbines. It is possible to increase the electricity generation by applying a 'bottoming cycle' in the form of a steam or an ORC cycle. Such a plant with ORC has been started in Austria this year. During the 1990's expectations were high concerning the development of biomass gasification with gas turbine in a combined cycle BIG-CC (Biomass Integrated Gasification Combined Cycle) towards commercialisation. Two demonstration plants were built for the same gas turbine model, Siemens SGT 100 (earlier Typhoon); Vaernamo with pressurised gasification and ARBRE in Eggborough, England, with atmospheric gasification. The atmospheric technology has basically the same demands on gas cleaning as in the engine application, but downstream the gas is compressed to the pressure required by the gas turbine. In pressurised gasification, the gasifier pressure is set by the gas turbine. The gas is not cooled below 350-400 deg C and is cleaned in a high-temperature filter. Despite successful demonstration in Vaernamo, no more plants have been built. The ARBRE plant was never put into regular

  6. Gasification of black liquor

    Science.gov (United States)

    Kohl, Arthur L.

    1987-07-28

    A concentrated aqueous black liquor containing carbonaceous material and alkali metal sulfur compounds is treated in a gasifier vessel containing a relatively shallow molten salt pool at its bottom to form a combustible gas and a sulfide-rich melt. The gasifier vessel, which is preferably pressurized, has a black liquor drying zone at its upper part, a black liquor solids gasification zone located below the drying zone, and a molten salt sulfur reduction zone which comprises the molten salt pool. A first portion of an oxygen-containing gas is introduced into the gas space in the gasification zone immediatley above the molten salt pool. The remainder of the oxygen-containing gas is introduced into the molten salt pool in an amount sufficient to cause gasification of carbonaceous material entering the pool from the gasification zone but not sufficient to create oxidizing conditions in the pool. The total amount of the oxygen-containing gas introduced both above the pool and into the pool constitutes between 25 and 55% of the amount required for complete combustion of the black liquor feed. A combustible gas is withdrawn from an upper portion of the drying zone, and a melt in which the sulfur content is predominantly in the form of alkali metal sulfide is withdrawn from the molten salt sulfur reduction zone.

  7. Combustion, pyrolysis, gasification, and liquefaction of biomass

    Energy Technology Data Exchange (ETDEWEB)

    Reed, T.B.

    1980-09-01

    All the products now obtained from oil can be provided by thermal conversion of the solid fuels biomass and coal. As a feedstock, biomass has many advantages over coal and has the potential to supply up to 20% of US energy by the year 2000 and significant amounts of energy for other countries. However, it is imperative that in producing biomass for energy we practice careful land use. Combustion is the simplest method of producing heat from biomass, using either the traditional fixed-bed combustion on a grate or the fluidized-bed and suspended combustion techniques now being developed. Pyrolysis of biomass is a particularly attractive process if all three products - gas, wood tars, and charcoal - can be used. Gasification of biomass with air is perhaps the most flexible and best-developed process for conversion of biomass to fuel today, yielding a low energy gas that can be burned in existing gas/oil boilers or in engines. Oxygen gasification yields a gas with higher energy content that can be used in pipelines or to fire turbines. In addition, this gas can be used for producing methanol, ammonia, or gasoline by indirect liquefaction. Fast pyrolysis of biomass produces a gas rich in ethylene that can be used to make alcohols or gasoline. Finally, treatment of biomass with high pressure hydrogen can yield liquid fuels through direct liquefaction.

  8. Combustion, pyrolysis, gasification, and liquefaction of biomas

    Science.gov (United States)

    Reed, T. B.

    1980-09-01

    The advantages of biomass as a feedstock are examined and biomass conversion techniques are described. Combustion is the simplest method of producing heat from biomass, using either the traditional fixed bed combustion on a grate or the fluidized bed and suspended combustion techniques now being developed. Pyrolysis of biomass is a particularly attractive process if all three products gas, wood tars, and charcoal can be used. Gasification of biomass with air is perhaps the most flexible and best developed process for conversion of biomass to fuel, yielding a low energy gas that can be burned in existing gas/oil boilers or in engines. Oxygen gasification yields a gas with higher energy content that can be used in pipelines or to fire turbines. In addition, this gas can be used for producing methanol, ammonia, or gasoline by indirect liquefaction. Fast pyrolysis of biomass produces a gas rich in ethylene that can be used to make alcohols or gasoline. Finally, treatment of biomass with high pressure hydrogen can yield liquid fuels through direct liquefaction.

  9. Gasification of municipal solid waste in the Plasma Gasification Melting process

    International Nuclear Information System (INIS)

    Highlights: ► 6 tests are conducted to study the performance of a PGM reactor. ► For air gasification, increasing ER will decrease syngas LHV value. ► Increasing ER will increase syngas yield and energy efficiency. ► High-temperature steam injection can significantly increase syngas yield. ► High-temperature steam injection will also increase syngas LHV value. -- Abstract: A new waste-disposal technology named Plasma Gasification Melting (PGM) was developed. A pilot PGM reactor was constructed in northern Israel. The reactor is an updraft moving-bed gasifier, with plasma torches placed next to air nozzles to heat the incoming air to 6000 °C. The inorganic substances of the feedstock are melted by the high-temperature air to form a vitrified slag in which undesirable materials such as heavy metals are trapped. The residual heat in the air supplies additional heat for the gasification process. A series of tests were conducted to study the performance of PGM gasification. The plasma power was varied from 2.88 to 3.12 MJ/kg of municipal solid waste (MSW), and the equivalence ratio (ER) was varied from 0.08 to 0.12. For air and steam gasification, the maximum steam/MSW mass ratio reached 0.33. The composition of the syngas product was analyzed in all tests; the lower heating value (LHV) of the syngas varied from 6 to 7 MJ/Nm3. For air gasification, the syngas LHV decreased with increasing ER, whereas the gas yield and energy efficiency increased with ER. When high-temperature steam was fed into the reactor, the overall gas yield was increased significantly, and the syngas LHV also increased slightly. The positive effect may be attributed to the steam reforming of tar. In air and steam gasification, the influence of increased ER on syngas LHV was negative, while the effect of increased plasma power was positive. The maximum energy efficiency of the tests reached 58%. The main energy loss was due to the formation of tar.

  10. Research on low emission MSW gasification and melting system

    Institute of Scientific and Technical Information of China (English)

    XIAO Gang; NI Mingjiang; CHI Yong; JIN Yuqi; ZHANG Jiaquan; MIAO Qi; CEN Kefa

    2007-01-01

    In order to eliminate secondary pollution caused by municipal solid waste (MSW) incineration,a MSW gasification and melting process is proposed.The process is expected to reduce the emission of pollutants,especially heavy-metals and dioxins.In this paper,the combustible components of MSW and simulated MSW were gasified in a lab-scale fluidized bed at 400℃-700℃ when the excess air ratio (ER) was between 0.2 and 0.8.The experimental results indicated that the MSW could be gasified effectively in a fluidized bed at approximately 600℃-700℃ when excess air ratio was 0.2-0.4.The melting characteristics of two typical fly ash samples from MSW incinerators were investigated.The results indicated that fly ash of pure MSW incineration could be melted at approximately 1,300℃ and that of MSW and coal co-combustion could be melted at approximately 1,400℃.When temperature was over 1,100℃,more than 99.9% of the dioxins could be decomposed and most of the heavy-metals could be solidified in the slag.Based on the above experiments,two feasible MSW gasification and melting processes were proposed for low calorific value MSW:(1) sieved MSW gasification and melting system,which was based on an idea of multi-recycle;(2) gasification and melting scheme of MSW adding coal as assistant fuel.

  11. Tar Management and Recycling in Biomass Gasification and Syngas Purification

    Science.gov (United States)

    McCaffrey, Zach

    Removal of tars is critical to the design and operation of biomass gasification systems as most syngas utilization processing equipment (e.g. internal combustion engines, gas turbines, fuel cells, and liquid fuel synthesis reactors) have a low tolerance for tar. Capturing and disposal of tar is expensive due to equipment costs, high hazardous waste disposal costs where direct uses cannot be found, and system energy losses incurred. Water scrubbing is an existing technique commonly used in gasification plants to remove contaminants and tar; however using water as the absorbent is non-ideal as tar compounds have low or no water solubility. Hydrophobic solvents can improve scrubber performance and this study evaluated tar solubility in selected solvents using slip-streams of untreated syngas from a laboratory fluidized bed reactor operated on almond composite feedstock using both air and steam gasification. Tar solubility was compared with Hansen's solubility theory to examine the extent to which the tar removal can be predicted. As collection of tar without utilization leads to a hazardous waste problem, the study investigated the effects of recycling tars back into the gasifier for destruction. Prior to experiments conducted on tar capture and recycle, characterizations of the air and steam gasification of the almond composite mix were made. This work aims to provide a better understanding of tar collection and solvent selection for wet scrubbers, and to provide information for designing improved tar management systems for biomass gasification.

  12. Investigation of polycyclic aromatic hydrocarbons from coal gasification

    Institute of Scientific and Technical Information of China (English)

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

    2005-01-01

    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.

  13. Gaseous fuels production from dried sewage sludge via air gasification.

    Science.gov (United States)

    Werle, Sebastian; Dudziak, Mariusz

    2014-06-17

    Gasification is a perspective alternative method of dried sewage sludge thermal treatment. For the purpose of experimental investigations, a laboratory fixed-bed gasifier installation was designed and built. Two sewage sludge (SS) feedstocks, taken from two typical Polish wastewater treatment systems, were analysed: SS1, from a mechanical-biological wastewater treatment system with anaerobic stabilization (fermentation) and high temperature drying; and (SS2) from a mechanical-biological-chemical wastewater treatment system with fermentation and low temperature drying. The gasification results show that greater oxygen content in sewage sludge has a strong influence on the properties of the produced gas. Increasing the air flow caused a decrease in the heating value of the produced gas. Higher hydrogen content in the sewage sludge (from SS1) affected the produced gas composition, which was characterized by high concentrations of combustible components. In the case of the SS1 gasification, ash, charcoal, and tar were produced as byproducts. In the case of SS2 gasification, only ash and tar were produced. SS1 and solid byproducts from its gasification (ash and charcoal) were characterized by lower toxicity in comparison to SS2. However, in all analysed cases, tar samples were toxic. PMID:24938297

  14. Improvement of biomass char-CO2 gasification reactivity using microwave irradiation and natural catalyst

    International Nuclear Information System (INIS)

    Highlights: • We study microwave-induced gasification of EFB ash-loaded biomass char with CO2. • Synergistic effect of microwave and catalyst resulted in CO2 conversion of 93%. • Gasification of pristine char using conventional heating gives CO2 conversion of 58%. • Ea of 74 and 247 kJ/mol were obtained for microwave and conventional CO2 gasification. - Abstract: In char-CO2 gasification, the highly endothermic nature of the Boudouard reaction (CO2 (g) + C (s) ↔ 2CO (g)) dictates use of very high temperatures to shift the equilibrium towards CO production. In this study, such high temperature (750–900 °C) was provided by microwave irradiation. A microwave heating system was developed to perform the gasification tests by passing CO2 through a packed bed of oil palm shell (OPS) char. In order to speed up the microwave-induced CO2 gasification, ash of palm empty fruit bunch (EFB) was used as natural catalyst (rich in potassium) and incorporated into the skeleton of the OPS char. The synergistic effect of microwave and catalyst concluded to very encouraging results, where a CO2 conversion of 93% was achieved at 900 °C, within 60 min microwave gasification. In comparison, CO2 conversion in thermal gasification (conventional heating) of pristine OPS char was only 58% under the same operating condition

  15. Improvement of biomass char-CO{sub 2} gasification reactivity using microwave irradiation and natural catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Lahijani, Pooya, E-mail: pooya.lahijani@gmail.com [Biomass and Bioenergy Laboratory, School of Mechanical Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang (Malaysia); Mohammadi, Maedeh, E-mail: m.mohammadi@nit.ac.ir [Faculty of Chemical Engineering, Babol Noushirvani University of Technology, 47148 Babol (Iran, Islamic Republic of); Zainal, Zainal Alimuddin, E-mail: mezainal@eng.usm.my [Biomass and Bioenergy Laboratory, School of Mechanical Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang (Malaysia); Mohamed, Abdul Rahman, E-mail: chrahman@usm.my [Low Carbon Economy (LCE) Research Group, School of Chemical Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang (Malaysia)

    2015-03-20

    Highlights: • We study microwave-induced gasification of EFB ash-loaded biomass char with CO{sub 2}. • Synergistic effect of microwave and catalyst resulted in CO{sub 2} conversion of 93%. • Gasification of pristine char using conventional heating gives CO{sub 2} conversion of 58%. • E{sub a} of 74 and 247 kJ/mol were obtained for microwave and conventional CO{sub 2} gasification. - Abstract: In char-CO{sub 2} gasification, the highly endothermic nature of the Boudouard reaction (CO{sub 2} (g) + C (s) ↔ 2CO (g)) dictates use of very high temperatures to shift the equilibrium towards CO production. In this study, such high temperature (750–900 °C) was provided by microwave irradiation. A microwave heating system was developed to perform the gasification tests by passing CO{sub 2} through a packed bed of oil palm shell (OPS) char. In order to speed up the microwave-induced CO{sub 2} gasification, ash of palm empty fruit bunch (EFB) was used as natural catalyst (rich in potassium) and incorporated into the skeleton of the OPS char. The synergistic effect of microwave and catalyst concluded to very encouraging results, where a CO{sub 2} conversion of 93% was achieved at 900 °C, within 60 min microwave gasification. In comparison, CO{sub 2} conversion in thermal gasification (conventional heating) of pristine OPS char was only 58% under the same operating condition.

  16. Fuel Flexibility in Gasification

    Energy Technology Data Exchange (ETDEWEB)

    McLendon, T. Robert; Pineault, Richard L.; Richardson, Steven W.; Rockey, John M.; Beer, Stephen K. (U.S. DOE National Energy Technology Laboratory); Lui, Alain P.; Batton, William A. (Parsons Infrastructure and Technology Group, Inc.)

    2001-11-06

    In order to increase efficiencies of carbonizers, operation at high pressures is needed. In addition, waste biomass fuels of opportunity can be used to offset fossil fuel use. The National Energy Technology Laboratory (NETL) Fluidized Bed Gasifier/Combustor (FBG/C) was used to gasify coal and mixtures of coal and biomass (sawdust) at 425 psig. The purpose of the testing program was to generate steady state operating data for modeling efforts of carbonizers. A test program was completed with a matrix of parameters varied one at a time in order to avoid second order interactions. Variables were: coal feed rate, pressure, and varying mixtures of sawdust and coal types. Coal types were Montana Rosebud subbituminous and Pittsburgh No. 8 bituminous. The sawdust was sanding waste from a furniture manufacturer in upstate New York. Coal was sieved from -14 to +60 mesh and sawdust was sieved to -14 mesh. The FBG/C operates at a nominal 425 psig, but pressures can be lowered. For the tests reported it was operated as a jetting, fluidized bed, ash-agglomerating gasifier. Preheated air and steam are injected into the center of the bottom along with the solid feed that is conveyed with cool air. Fairly stable reactor internal flow patterns develop and temperatures stabilize (with some fluctuations) when steady state is reached. At nominal conditions the solids residence time in the reactor is on the order of 1.5 to 2 hours, so changes in feed types can require on the order of hours to equilibrate. Changes in operating conditions (e.g. feed rate) usually require much less time. The operating periods of interest for these tests were only the steady state periods, so transient conditions were not monitored as closely. The test matrix first established a base case of operations to which single parameter changes in conditions could be compared. The base case used Montana Rosebud at a coal feed rate of 70 lbm/hr at 425 psig. The coal sawdust mixtures are reported as percent by weight

  17. Coal gasification and its applications

    Energy Technology Data Exchange (ETDEWEB)

    Bell, D.; Towler, B.

    2010-07-01

    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.

  18. Modeling of biomass gasification

    International Nuclear Information System (INIS)

    Full text: Optimal conversion of chemical energy of the biomass or other solid fuel into the desired gas depends on proper configuration, sizing, and choice of gasifier operating conditions. Optimum operating conditions are often derived through trials on the unit or by experiments on pilot plants. Simulation, or mathematical modeling, allows the designer or plant engineer to reasonably optimize the operation or the design of the plant. The good mathematical model can: find optimum operating conditions or a design for the gasifier, provide information on extreme operating conditions (high temperature, high pressure) where experiments are difficult to perform, provide information over a much wider range of conditions than one can obtain experimentally, better interpret experimental results and analyze abnormal behavior of a gasifier, if that occurs, assist scale-up of the gasifier from one successfully operating size to another, and from one feedstock to another. The equilibrium model is independent of the gasifier design which can make them more suitable for a system study of the most important process parameters. The use of an equilibrium model assumes that the residence time of the reactants in the gasifier is high enough to reach chemical equilibrium. For established biomass ultimate analysis, temperature of gasification air and temperature of produced gas, combining the mass balance equations with the equations for the equilibrium constants and equation of energy balance, the equivalence ratio (ER) and composition of produced gas can be obtained. A mathematical model for investigation of the influence of temperature of the produced gas and temperature of gasification air on the process parameters was developed. It can be used for estimation and design of gasification equipment. key words: biomass gasification, mathematical modeling, equilibrium model

  19. Biomass Gasification Combined Cycle

    Energy Technology Data Exchange (ETDEWEB)

    Judith A. Kieffer

    2000-07-01

    Gasification combined cycle continues to represent an important defining technology area for the forest products industry. The ''Forest Products Gasification Initiative'', organized under the Industry's Agenda 2020 technology vision and supported by the DOE ''Industries of the Future'' program, is well positioned to guide these technologies to commercial success within a five-to ten-year timeframe given supportive federal budgets and public policy. Commercial success will result in significant environmental and renewable energy goals that are shared by the Industry and the Nation. The Battelle/FERCO LIVG technology, which is the technology of choice for the application reported here, remains of high interest due to characteristics that make it well suited for integration with the infrastructure of a pulp production facility. The capital cost, operating economics and long-term demonstration of this technology area key input to future economically sustainable projects and must be verified by the 200 BDT/day demonstration facility currently operating in Burlington, Vermont. The New Bern application that was the initial objective of this project is not currently economically viable and will not be implemented at this time due to several changes at and around the mill which have occurred since the inception of the project in 1995. The analysis shows that for this technology, and likely other gasification technologies as well, the first few installations will require unique circumstances, or supportive public policies, or both to attract host sites and investors.

  20. Gasification of fuel blends from biomass and wastes

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Arne [Lund Univ. (Sweden). Dept. of Chemical Engineering II

    2000-04-01

    Pressurized air-blown fluidized-bed gasification of biomass and biomass-based fuel blends were carried out at LTH. The operation was stable and smooth. The fluidized-bed functioned well in keeping a stable gasification and homogeneous conditions along the reactor. Parameters, such as the equivalent ratio, the bed temperature and the freeboard temperature were studied. It was found that the equivalent ratio was the dominant factor when the carbon conversion was complete. The energy content of the fuel gas, the fuel gas production, and the amount of tar and LHCs increased with decreasing equivalent ratio. Low freeboard and bed temperatures can lead to low carbon conversion and low gasification efficiency. Below 100% carbon conversion, the fuel-N conversion to ammonia increased with increasing reactor temperature. The tendency was similar for the carbon conversion to gas, but it was more pronounced. A high reactor temperature helped to reduce the amount of LHCs and tar in the fuel gas. Fuel blends with plastic or carton waste in biomass were successfully gasified. A waste fraction of 20% was found practical. Higher ratio may cause blocking in the feeding system for carton and demand special care to control the equivalent ratio for plastics. No melting problem was observed for plastics. The product gas quality was not much affected by adding the wastes. No clear increase of the chlorine content in the fuel gas was observed. However mixing of plastics greatly increased the amounts of LHCs and tar in the fuel gas. In general, introducing a small amount of plastic and carton wastes into biomass gasification will not require much change in the gasification system. This gives rise to the possibility of co-gasifying wastes in an ordinary biomass gasifier. From lab-scale experiments, a model for ammonia decomposition was proposed. A Ni-based catalyst was chosen to be applied for the fuel gas from the gasifier. At 800-900 deg C, and 3-sec space-time, 65-95% ammonia removal and

  1. Prevention of the ash deposits by means of process conditions in biomass gasification; Biomassapolttoaineiden tuhkan kuonaantumiskaeyttaeytymisen estaeminen prosessiolosuhteiden avulla

    Energy Technology Data Exchange (ETDEWEB)

    Moilanen, A.; Laatikainen-Luntama, J.; Nieminen, M.; Kurkela, E.; Korhonen, J. [VTT Energy, Espoo (Finland)

    1997-10-01

    In fluidised-bed gasification, various types of deposits and agglomerates may be formed by biomass ash in the bed, in upper zones of the reactor, for instance in cyclones. These may decisively hamper the operation of the process. The aim of the project was to obtain data on the detrimental fouling behaviour of the ash of different types of biomass in fluidised-bed gasification, and on the basis of these data to determine the process conditions and ways of preventing this kind of behaviour. Different types of biomass fuel relevant to energy production such as straw, wood residue were be used as samples. The project consisted of laboratory studies and fluidised-bed reactor tests including ash behaviour studied both in the bed and freeboard. In laboratory tests, the sample material was characterised as a function of different process parameters. In fluid-bed reactors, the most harmful biomasses were tested using process variables such as temperature, bed material and the gasification agents. Bubbling fluidised-bed gasification tests with wheat straw showed that agglomerates with different sizes and structures formed in the bed depending on the temperature, the feed gas composition and bed material. Agglomerates consisted of molten ash which sintered with bed material and other solids. In all BFB tests, freeboard walls were slicked by ash agglomerates (different amounts) which, however, were easily removable. The results of this project and the earlier pilot-scale gasification experience obtained with the same feedstocks showed that useful characteristic data about ash behaviour can be obtained using laboratory tests and small scale reactors. (orig.)

  2. Biomass Gasification - A synthesis of technical barriers and current research issues for deployment at large scale

    Energy Technology Data Exchange (ETDEWEB)

    Heyne, Stefan [Chalmers Univ. of Technology, Gothenburg (Sweden); Liliedahl, Truls [KTH, Royal Inst. of Technology, Stockholm (Sweden); Marklund, Magnus [Energy Technology Centre, Piteaa (Sweden)

    2013-09-01

    Thermal gasification at large scale for cogeneration of power and heat and/or production of fuels and materials is a main pathway for a sustainable deployment of biomass resources. However, so far no such full scale production exists and biomass gasification projects remain at the pilot or demonstration scale. This report focuses on the key critical technology challenges for the large-scale deployment of the following biomass-based gasification concepts: Direct Fluidized Bed Gasification (FBG), Entrained Flow Gasification (EFG) and indirect Dual Fluidized Bed Gasification (DFBG). The main content in this report is based on responses from a number of experts in biomass gasification obtained from a questionnaire. The survey was composed of a number of more or less specific questions on technical barriers as to the three gasification concepts considered. For formalising the questionnaire, the concept of Technology Readiness Level (TRL 1-9) was used for grading the level of technical maturity of the different sub-processes within the three generic biomass gasification technologies. For direct fluidized bed gasification (FBG) it is mentioned that the technology is already available at commercial scale as air-blown technology and thus that air-blown FBG gasification may be reckoned a mature technology. The remaining technical challenge is the conversion to operation on oxygen with the final goal of producing chemicals or transport fuels. Tar reduction, in particular, and gas cleaning and upgrading in general are by far the most frequently named technical issues considered problematic. Other important aspects are problems that may occur when operating on low-grade fuels - i.e. low-cost fuels. These problems include bed agglomeration/ash sintering as well as alkali fouling. Even the preparation and feeding of these low-grade fuels tend to be problematic and require further development to be used on a commercial scale. Furthermore, efficient char conversion is mentioned by

  3. Guideline for safe and eco-friendly biomass gasification

    Energy Technology Data Exchange (ETDEWEB)

    Vos, J.; Knoef, H. (BTG biomass technology group, Enschede (Netherlands)); Hauth, M. (Graz Univ. of Technology. Institute of Thermal Engineering, Graz (Austria)) (and others)

    2009-11-15

    The objective of the Gasification Guide project is to accelerate the market penetration of small-scale biomass gasification systems (< 5 MW fuel power) by the development of a Guideline and Software Tool to facilitate risk assessment of HSE aspects. The Guideline may also be applied in retrofitting or converting old thermal plants in the Eastern European countries - with rich biomass recourses - to new gasification plants. The objective of this document is to guide key target groups identifying potential hazards and make a proper risk assessment. The software tool is an additional aid in the risk assessment. This guideline is intended to be a training tool and a resource for workers and employers to safely design, fabricate, construct, operate and maintain small-scale biomass gasification facilities. The Guideline is applicable with the following constraints: 1) The maximum scale of the gasification plant was agreed to be about 1 MW{sub e}. The reason is that large companies do have normally their safety rules in place; 2) This means in principle only fixed bed gasifier designs. However, most parts are also valid to other designs and even other thermal conversion processes; 3) The use of contaminated biomass is beyond the scope of this Guideline. The Guideline contains five major chapters; Chapter 2 briefly describes the gasification technology in general. Chapter 3 gives an overview of major legal framework issues on plant permission and operation. The legal frame is changing and the description is based on the situation by the end of 2007. Chapter 4 explains the theory behind the risk assessment method and risk reduction measures. Chapter 5 is the heart of the Guideline and gives practical examples of good design, operation and maintenance principles. The practical examples and feedback have been received throughout the project and the description is based on mid-2009. Chapter 6 describes the best techniques currently available for emission abatement which are

  4. Bio-syngas production from biomass catalytic gasification

    International Nuclear Information System (INIS)

    A promising application for biomass is liquid fuel synthesis, such as methanol or dimethyl ether (DME). Previous studies have studied syngas production from biomass-derived char, oil and gas. This study intends to explore the technology of syngas production from direct biomass gasification, which may be more economically viable. The ratio of H2/CO is an important factor that affects the performance of this process. In this study, the characteristics of biomass gasification gas, such as H2/CO and tar yield, as well as its potential for liquid fuel synthesis is explored. A fluidized bed gasifier and a downstream fixed bed are employed as the reactors. Two kinds of catalysts: dolomite and nickel based catalyst are applied, and they are used in the fluidized bed and fixed bed, respectively. The gasifying agent used is an air-steam mixture. The main variables studied are temperature and weight hourly space velocity in the fixed bed reactor. Over the ranges of operating conditions examined, the maximum H2 content reaches 52.47 vol%, while the ratio of H2/CO varies between 1.87 and 4.45. The results indicate that an appropriate temperature (750 oC for the current study) and more catalyst are favorable for getting a higher H2/CO ratio. Using a simple first order kinetic model for the overall tar removal reaction, the apparent activation energies and pre-exponential factors are obtained for nickel based catalysts. The results indicate that biomass gasification gas has great potential for liquid fuel synthesis after further processing

  5. PNNL Coal Gasification Research

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-07-28

    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.

  6. Combined catalytic partial oxidation and CO2 reforming of methane over ZrO2-modified Ni/SiO2 catalysts using fluidized-bed reactor

    International Nuclear Information System (INIS)

    Nickel on zirconium-modified silica was prepared and tested as a catalyst for reforming methane with CO2 and O2 in a fluidized-bed reactor. A conversion of CH4 near thermodynamic equilibrium and low H2/CO ratio (12/CO2-temperature reaction (H2-TPR), CO2-temperature desorption (CO2-TPD) and transmission election microscope (TEM) techniques. Ni sintering was a major reason for the deactivation of pure Ni/SiO2 catalysts, while Ni dispersed highly on a zirconium-promoted Ni/SiO2 catalyst. The different kinds of surface Ni species formed on ZrO2-promoted catalysts might be responsible for its high activity and good resistance to Ni sintering

  7. Combination of upflow anaerobic sludge blanket (UASB) reactor and partial nitritation/anammox moving bed biofilm reactor (MBBR) for municipal wastewater treatment.

    Science.gov (United States)

    Malovanyy, Andriy; Yang, Jingjing; Trela, Jozef; Plaza, Elzbieta

    2015-03-01

    In this study the combination of an upflow anaerobic sludge blanket (UASB) reactor and a deammonification moving bed biofilm reactor (MBBR) for mainstream wastewater treatment was tested. The competition between aerobic ammonium oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) was studied during a 5months period of transition from reject water to mainstream wastewater followed by a 16months period of mainstream wastewater treatment. The decrease of influent ammonium concentration led to a wash-out of suspended biomass which had a major contribution to nitrite production. Influence of a dissolved oxygen concentration and a transient anoxia mechanism of NOB suppression were studied. It was shown that anoxic phase duration has no effect on NOB metabolism recovery and oxygen diffusion rather than affinities of AOB and NOB to oxygen determine the rate of nitrogen conversion in a biofilm system. Anammox activity remained on the level comparable to reject water treatment systems. PMID:25600011

  8. Gasification biochar as a valuable by-product for carbon sequestration and soil amendment

    DEFF Research Database (Denmark)

    Hansen, Veronika; Müller-Stöver, Dorette Sophie; Ahrenfeldt, Jesper; Holm, Jens Kai; Henriksen, Ulrik Birk; Hauggaard-Nielsen, Henrik

    2015-01-01

    Thermal gasification of various biomass residues is a promising technology for combining bioenergy production with soil fertility management through the application of the resulting biochar as soil amendment. In this study, we investigated gasification biochar (GB) materials originating from two...... major global biomass fuels: straw gasification biochar (SGB) and wood gasification biochar (WGB), produced by a Low Temperature Circulating Fluidized Bed gasifier (LT-CFB) and a TwoStage gasifier, respectively, optimized for energy conversion. Stability of carbon in GB against microbial degradation was...... assessed in a shortterm soil incubation study and compared to the traditional practice of direct incorporation of cereal straw. The GBs were chemically and physically characterized to evaluate their potential to improve soil quality parameters. After 110 days of incubation, about 3% of the added GB carbon...

  9. Thermodynamic Analysis of an Integrated Gasification Solid Oxide Fuel Cell Plant with a Kalina Cycle

    DEFF Research Database (Denmark)

    Pierobon, Leonardo; Rokni, Masoud

    2015-01-01

    system based on a gasification plant, a SOFC plant and a SKC plant is presented and investigated. The system is called IGSKC (Integrated Gasification SOFC Simple Kalina Cycle). The system layout is studied, and the optimal ammonia-water mole fraction is selected. An electrical efficiency of 58% is......A hybrid plant that consists of a gasification system, Solid Oxide Fuel Cells (SOFC) and a Simple Kalina Cycle (SKC) is investigated. Woodchips are introduced into a fixed bed gasification plant to produce syngas, which is then fed into an integrated SOFC-SKC plant to produce electricity. The pre...... achieved; plant size and nominal power are selected based on the required cultivation area. SOFC heat recovery with SKC is compared to a Steam Cycle (SC). Although ammonia-water more accurately fits the temperature profile of the off-gases, the presence of a Hybrid Recuperator enhances the available work...

  10. The Development of Coke Carried—Heat Gasification Coal—Fired Combined Cycle

    Institute of Scientific and Technical Information of China (English)

    LiZhao; XiangdongXu

    1999-01-01

    Carried-Heat Partial Gasification Combined cycle is a novel combined cycle which was proposed by Thermal Engineering Department of Tsinghua University in 1992,The idea of the system comes from the situation that the efficiency of the power plants in china is much lower than that of the advanced countries,but the coal consumption is much higher,which brings about the waste of primary energy resources and the pollution of the environment.With the deep study of the gasification technology,Coke Carried-Heat Gasification Coal-Fired Combined Cycle,as the improved system,came into birth in 1996 based on the partial gasification one,At the end of 1997,a new cycle scheme similar to IGCC was created.This paper focuses on several classes combined cycle put forward by Tsinghua University,depending on the plant configuration and carbon conversion,making the solution a viable and attractive option for efficient coal utilization.

  11. Hydrogen production from algal biomass via steam gasification.

    Science.gov (United States)

    Duman, Gozde; Uddin, Md Azhar; Yanik, Jale

    2014-08-01

    Algal biomasses were tested as feedstock for steam gasification in a dual-bed microreactor in a two-stage process. Gasification experiments were carried out in absence and presence of catalyst. The catalysts used were 10% Fe₂O₃-90% CeO₂ and red mud (activated and natural forms). Effects of catalysts on tar formation and gasification efficiencies were comparatively investigated. It was observed that the characteristic of algae gasification was dependent on its components and the catalysts used. The main role of the catalyst was reforming of the tar derived from algae pyrolysis, besides enhancing water gas shift reaction. The tar reduction levels were in the range of 80-100% for seaweeds and of 53-70% for microalgae. Fe₂O₃-CeO₂ was found to be the most effective catalyst. The maximum hydrogen yields obtained were 1036 cc/g algae for Fucus serratus, 937 cc/g algae for Laminaria digitata and 413 cc/g algae for Nannochloropsis oculata. PMID:24880809

  12. Ash behaviour in fluidized bed gasification and combustion: release of harmful trace elements and the behavior of alkalis; Tuhkan muuntuminen leijukerroskaasutuksessa ja -poltossa: Haitallisten hivenmetallien vapautuminen ja alkalien kaeyttaeytyminen

    Energy Technology Data Exchange (ETDEWEB)

    Kauppinen, E.; Valmari, T. [VTT Chemical Technology, Espoo (Finland)

    1997-10-01

    During 1996 the behaviour of alkaline metals (K and Na) during circulating fluidized bed combustion of forest residue was studied in a real-scale plant using aerosol measurement instruments (filters, impactor, DMA). Prior to heat exchangers (850 deg C) the ash mass-concentration was 1.0 - 1.3 g/Nm{sup 3} with 1 % of ash forming constituents as vapours. At least 98 % of sulphur, over 90 % of sodium and over 80 % of potassium were found in particulate phase prior to heat exchangers. On the other hand, at least 80 % of the chlorine was in vapour phase. 98 % of the ash was in coarse (> 0.3 {mu}m) particles. Coarse ash particles had an irregular surface structure often consisting of fine primary particles. The remaining 2 % was observed in fine particles of about 0.1 {mu}m. Both rounded and cornered (suggesting crystal structure) fine particles were found. The fine particles were composed of alkali chlorides and sulphates, mainly of KCl. About 80 % of the ash on mass basis was deposited onto heat exchanger surfaces when soot-blowing was not carried out. Practically all of the particles larger than 10 {mu}m were deposited. The deposition was less significant for smaller particles. The fine particle concentration before and after the heat exchangers was the same within the experimental inaccuracy. The deposited fraction of potassium, sodium and sulphur was about the same than that of the total ash: However, the deposition of chlorine was much lower since the chlorine content was low in the coarse particles that were deposited most effectively. (orig.)

  13. Catalytic Hydrothermal Gasification

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, Douglas C.

    2015-05-31

    The term “hydrothermal” used here refers to the processing of biomass in water slurries at elevated temperature and pressure to facilitate the chemical conversion of the organic structures in biomass into useful fuels. The process is meant to provide a means for treating wet biomass materials without drying and to access ionic reaction conditions by maintaining a liquid water processing medium. Typical hydrothermal processing conditions are 523-647K of temperature and operating pressures from 4-22 MPa of pressure. The temperature is sufficient to initiate pyrolytic mechanisms in the biopolymers while the pressure is sufficient to maintain a liquid water processing phase. Hydrothermal gasification is accomplished at the upper end of the process temperature range. It can be considered an extension of the hydrothermal liquefaction mechanisms that begin at the lowest hydrothermal conditions with subsequent decomposition of biopolymer fragments formed in liquefaction to smaller molecules and eventually to gas. Typically, hydrothermal gasification requires an active catalyst to accomplish reasonable rates of gas formation from biomass.

  14. Evaluation of biomass gasification in a ternary diagram

    International Nuclear Information System (INIS)

    The present paper addresses the development of an alternative approach to illustrate biomass gasification in a ternary diagram which is constructed using data from thermodynamic equilibrium modeling of air-blown atmospheric wood gasification. It allows the location of operation domains of slagging entrained-flow, fluidized-bed/dry-ash entrained-flow and fixed/moving-bed gasification systems depending on technical limitations mainly due to ash melting behavior. Performance parameters, e.g. cold gas efficiency or specific syngas production, and process parameters such as temperature and carbon conversion are displayed in the diagram depending on the three independent mass flows representing (1) the gasifying agent, (2) the dry biomass and (3) the moisture content of the biomass. The graphical approach indicates the existence of maxima for cold gas efficiency (84.9%), syngas yield (1.35 m3 (H2 + CO STP)/kg (waf)) and conversion of carbon to CO (81.1%) under dry air-blown conditions. The fluidized-bed/dry-ash entrained-flow processes have the potential to reach these global maxima since they can operate in the identified temperature range from 700 to 950 °C. Although using air as a gasifying agent, the same temperature range posses a potential of H2/CO ratios up to 2.0 at specific syngas productions of 1.15 m3 (H2 + CO STP)/kg (waf). Fixed/moving-bed and fluidized-bed systems can approach a dry product gas LHV from 3.0 to 5.5 MJ/m3 (dry STP). The ternary diagram was also used to study the increase of gasifying agent oxygen fraction from 21 to 99 vol.%. While the dry gas LHV can be increased significantly, the maxima of cold gas efficiency (+6.5%) and syngas yield (+7.4%) are elevated only slightly. - Highlights: • Novel graphical approach for comprehensive assessment of biomass gasification. • Parameters fields for temperature, conversion, cold gas efficiency, syngas yield etc. • Identification of operation ranges for entrained, fluid and moving-bed

  15. Bed to wall heat transfer in supercritical water fluidized bed: Comparison with the gas–solid fluidized bed

    International Nuclear Information System (INIS)

    Supercritical water (SCW) fluidized bed is a new reactor concept for gasification of wet biomass. In this paper, the Eulerian two-fluid model based on Kinetic Theory of Granular Flow in fluidized bed was established, and the physical model of movement of single bubble up the wall was adopted. The comparison studies of particle distribution, temperature distribution and transient heat transfer characteristics between the SCW and gas–solid fluidized bed were carried out. The results show that the bubble diameter and rise velocity in SCW fluidized bed are smaller than those in gas–solid fluidized bed. With the increasing solid volume fraction near the wall, the bed-to-wall heat transfer coefficient decreases in SCW fluidized bed, while it increases in gas–solid fluidized bed. What is more, the bed-to-wall heat transfer coefficient is sensitive to superficial velocity where the solid volume fraction is low, which is different from that in gas–solid fluidized bed

  16. The development of solid fuel gasification systems for cost-effective power generation with low environmental impacts

    Energy Technology Data Exchange (ETDEWEB)

    Nieminen, M.; Kurkela, E.; Staahlberg, P.; Laatikainen-Luntama, J.; Ranta, J.; Hepola, J.; Kangasmaa, K. [VTT Energy, Espoo (Finland). Gasification and Advanced Combustion

    1997-10-01

    Relatively low carbon conversion is a disadvantage related to the air-blown fluidised-bed coal-biomass co-gasification process. Low carbon conversion is due to different reactivities and ash sintering behaviour of coal and biomass which leads to compromises in definition of gasification process conditions. In certain cases co-gasification may also lead to unexpected deposit formations or corrosion problems in downstream components especially when high alkali metal or chlorine containing biomass feedstocks are co-gasified with coal. During the reporting period, the work focused on co-gasification of coal and wood waste. The objectives of the present work were to find out the optimum conditions for improving the carbon conversion and to study the formation of different gas impurities. The results based on co-gasification tests with a pressurised fluidised-bed gasifies showed that in co-gasification even with only 15 % coal addition the heavy tar concentration was decreased significantly and, simultaneously, an almost total carbon conversion was achieved by optimising the gasification conditions. The study of filter fines recirculation and solid residues utilisation was started by characterizing filter dust. The work was carried out with an entrained-flow reactor in oxidising, inert and reducing gas conditions. The aim was to define the conditions required for achieving increased carbon conversion in different reactor conditions

  17. Experimental Fact-Finding in CFB Biomass Gasification for ECN's 500 kWth Pilot Plant

    NARCIS (Netherlands)

    Kersten, S.R.A.; Prins, W.; Drift, van der A.; Swaaij, van W.P.M.

    2003-01-01

    CFB biomass gasification has been studied by experimentation with ECN's pilot facility and a cold-flow model of this plant. Data obtained by normal operation of this plant and the results of some special experiments have provided new insight into the behavior of circulating fluidized bed reactors an

  18. Co-combustion and gasification of various biomasses

    Energy Technology Data Exchange (ETDEWEB)

    Mutanen, K. [A. Ahlstrom Corporation, Varkaus (Finland). Ahlstrom Pyropower

    1996-12-31

    During the last twenty years the development of fluidized bed combustion and gasification technology has made it possible to increase significantly utilisation of various biomasses in power and heat generation. The forerunner was the pulp and paper industry that has an adequate biomass fuel supply and energy demand on site. Later on municipalities and even utilities have seen biomass as a potential fuel. The range of available biomasses includes wood-based fuels and wastes like bark, wood chips, and saw dust, agricultural wastes like straw, olive waste and rice husk, sludges from paper mills and de-inking plants, other wastes like municipal sludges, waste paper and RDF. Recently new environmental regulations and taxation of fossil fuels have further increased interest in the use of biomasses in energy generation. However, in many cases available quantities and/or qualities of biomasses are not adequate for only biomass-based energy generation in an economic sense. On the other hand plant owners want to maintain a high level of fuel flexibility and fuel supply security. In some cases disposing by burning is the only feasible way to handle certain wastes. In many cases the only way to fulfil these targets and utilize the energy is to apply co-combustion or gasification of different fuels and wastes. Due to the fact that fluidized bed combustion technology offers a very high fuel flexibility and high combustion efficiency with low emissions it has become the dominating technology in co-combustion applications. This presentation will present Alhstrom`s experiences in co-combustion of biomasses in bubbling beds and Ahlstrom Pyroflow circulating fluidized beds based on about 200 operating references worldwide. CFB gasification will also be discussed 9 refs.

  19. Catalytic hot gas cleaning of gasification gas

    Energy Technology Data Exchange (ETDEWEB)

    Simell, P. [VTT Energy, Espoo (Finland). Energy Production Technologies

    1997-12-31

    The aim of this work was to study the catalytic cleaning of gasification gas from tars and ammonia. In addition, factors influencing catalytic activity in industrial applications were studied, as well as the effects of different operation conditions and limits. Also the catalytic reactions of tar and ammonia with gasification gas components were studied. The activities of different catalyst materials were measured with laboratory-scale reactors fed by slip streams taken from updraft and fluid bed gasifiers. Carbonate rocks and nickel catalysts proved to be active tar decomposing catalysts. Ammonia decomposition was in turn facilitated by nickel catalysts and iron materials like iron sinter and iron dolomite. Temperatures over 850 deg C were required at 2000{sup -1} space velocity at ambient pressure to achieve almost complete conversions. During catalytic reactions H{sub 2} and CO were formed and H{sub 2}O was consumed in addition to decomposing hydrocarbons and ammonia. Equilibrium gas composition was almost achieved with nickel catalysts at 900 deg C. No deactivation by H{sub 2}S or carbon took place in these conditions. Catalyst blocking by particulates was avoided by using a monolith type of catalyst. The apparent first order kinetic parameters were determined for the most active materials. The activities of dolomite, nickel catalyst and reference materials were measured in different gas atmospheres using laboratory apparatus. This consisted of nitrogen carrier, toluene as tar model compound, ammonia and one of the components H{sub 2}, H{sub 2}O, CO, CO{sub 2}, CO{sub 2}+H{sub 2}O or CO+CO{sub 2}. Also synthetic gasification gas was used. With the dolomite and nickel catalyst the highest toluene decomposition rates were measured with CO{sub 2} and H{sub 2}O. In gasification gas, however, the rate was retarded due to inhibition by reaction products (CO, H{sub 2}, CO{sub 2}). Tar decomposition over dolomite was modelled by benzene reactions with CO{sub 2}, H

  20. Entrained Flow Gasification of Biomass

    DEFF Research Database (Denmark)

    Qin, Ke

    The present Ph. D. thesis describes experimental and modeling investigations on entrained flow gasification of biomass and an experimental investigation on entrained flow cogasification of biomass and coal. A review of the current knowledge of biomass entrained flow gasification is presented....... Biomass gasification experiments were performed in a laboratory-scale atmospheric pressure entrained flow reactor with the aim to investigate the effects of operating parameters and biomass types on syngas products. A wide range of operating parameters was involved: reactor temperature, steam/carbon ratio......, excess air ratio, oxygen concentration, feeder gas flow, and residence time. Wood, straw, and lignin were used as biomass fuels. In general, the carbon conversion was higher than 90 % in the biomass gasification experiments conducted at high temperatures (> 1200 °C). The biomass carbon that was not...

  1. Centralized coke gasification study

    Energy Technology Data Exchange (ETDEWEB)

    du Plessis, Duke [Alberta Innovates (Canada); Pietrusik, Debbie [Alberta Finance and Enterprise (Canada)

    2011-07-01

    By the year 2020 Alberta will produce 3 million barrels of bitumen per day. Refining bitumen yields several by-products such as petroleum coke and off-gasses. These products can be further utilized as a low cost feedstock for additional applications to increase revenue. Alberta currently has the largest amount of coke stockpiled in the world. The presentation explores what is the most profitable way to use this coke and what future technologies would improve the economic and environmental impact of the process. The development of methane and hydrogen becomes competitive at intermediate gas and oil prices. The next generation of gasification technologies is going to be cheaper, efficient and much smaller. Pilot projects have shown positive results. Economies of scale can be reached simply by only 20-30% of annual coke production. The high cost of the current technology is creating the biggest challenge but new technologies and process innovations have the potential to drive down cost.

  2. Thermal Plasma Gasification of Biomass

    Czech Academy of Sciences Publication Activity Database

    Hrabovský, Milan

    Rijeka : InTech, 2011 - (Shahid Shaukat, S.), s. 39-62 ISBN 978-953-307-491-7 R&D Projects: GA ČR GAP205/11/2070 Institutional research plan: CEZ:AV0Z20430508 Keywords : thermal plasma * plasma gasification * biomass Subject RIV: BL - Plasma and Gas Discharge Physics http://www.intechopen.com/articles/show/title/thermal-plasma-gasification-of-biomass

  3. Experimental investigations of biomass gasification with carbon-dioxide

    Science.gov (United States)

    Sircar, Indraneel

    A sustainable energy cycle may include enhanced utilization of solar energy and atmospheric CO2 to produce biomass and enhanced utilization of exhaust CO2 from power plants for synthetic gas production. The reaction of carbon with CO2 is potentially one of the important processes in a future sustainable carbon cycle. Reactions involving carbon and CO2 are also relevant to the chemical process and metal industries. Biomass char has been recognized as a present and future alternative to fossil-fuels for energy production and fuel synthesis. Therefore, biomass char gasification with CO2 recycling is proposed as a sustainable and carbon-neutral energy technology. Biomass char is a complex porous solid and its gasification involves heat and mass transfer processes within pores of multiple sizes from nanometer to millimeter scales. These processes are coupled with heterogeneous chemistry at the internal and external surfaces. Rates for the heterogeneous carbon gasification reactions are affected by inorganic content of the char. Furthermore, pore structure of the char develops with conversion and influences apparent gasification rates. Effective modeling of the gasification reactions has relied on the best available understanding of diffusion processes and kinetic rate property constants from state of the art experiments. Improvement of the influences of inorganic composition, and process parameters, such as pressure and temperature on the gasification reaction rates has been a continuous process. Economic viability of gasification relies on use of optimum catalysts. These aspects of the current status of gasification technologies have motivated the work reported in this dissertation. The reactions between biomass chars and CO2 are investigated to determine the effects of temperature and pressure on the reaction rates for large char particles of relevance to practical gasification technologies. An experimental apparatus consisting of a high-pressure fixed-bed reactor

  4. Efficient gasification of wet biomass residue to produce middle caloric gas

    Institute of Scientific and Technical Information of China (English)

    Guangwen Xu; Takahiro Murakami; Toshiyuki Suda; Hidehisa Tani; Yutaka Mito

    2008-01-01

    Various process residues represent a kind of biomass resource already concentrated but containing water as much as 60 wt.%.These materials are generally treated as waste or simply combusted directly to generate heat.Recently,we attempted to convert them into middle caloric gas to substitute for natural gas,as a chemical or a high-rank gaseous fuel for advanced combustion utilities.Such conversion is implemented through dual fluidized bed gasification (DFBG).Concerning the high water content of the fuels,DFBG was suggested to accomplish either with high-efficiency fuel drying in advance or direct decoupling of fuel drying/pyrolysis from char gasification and tar/hydrocarbon reforming.Along with fuel drying,calcium-based catalyst can be impregnated into the fuel,without much additional cost,to increase the fuel's gasification reactivity and to reduce tar formation.This article reports the Ca impregnation method and its resulting effects on gasification reactivity and tar suppression ability.Meanwhile,the principle of directly gasifying wet fuel with decoupled dual fluidized bed gasification (D-DFBG) is also highlighted.

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

    Energy Technology Data Exchange (ETDEWEB)

    1990-12-01

    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.

  6. Biomass ash-bed material interactions leading to agglomeration in FBC

    DEFF Research Database (Denmark)

    Visser, H.J.M.; van Lith, Simone Cornelia; Kiel, J.H.A.

    2008-01-01

    In (bubbling) fluidized-bed combustion and gasification of biomass, several potential problems are associated with the inorganic components of the fuel. A major problem area is defluidization due to bed agglomeration. The most common found process leading to defluidization in commercial-scale ins...

  7. Engineering bed models for solid fuel conversion process in grate-fired boilers

    DEFF Research Database (Denmark)

    Costa, M.; Massarotti, N.; Indrizzi, V.;

    2014-01-01

    A comparison between two numerical models describing the thermo-chemical conversion process of a solid fuel bed in a grate-fired boiler is presented. Both models consider the incoming biomass as subjected to drying, pyrolysis, gasification and combustion. In the first approach the biomass bed is ...

  8. Evaluation of cyclone gasifier performance for gasification of sugar cane residue - Pt. 1: gasification of bagasse

    Energy Technology Data Exchange (ETDEWEB)

    Gabra, M.; Pettersson, E.; Kjellstrom, B. [Lulea University of Technology (Sweden). Div. of Energy Engineering; Backman, R. [Abo Akademi University, Abo (Finland). Div. of Chemical Engineering

    2001-11-01

    A method for avoiding excessive amount of alkali compounds and carryover particles in producer gas from gasification of sugar cane residue has been studied and evaluated. The cane sugar residue is gasified in a two-stage combustor at atmospheric pressure, where the first stage is a cyclone gasifier. The cyclone works as particle separator as well. This paper covers the results obtained for gasification of bagasse. Bagasse powder was injected into the cyclone with air and steam as transport medium. The gasification tests were made with two feeding rates, 39 and 52 kg/h. Seven experiments were conducted with the equivalence ratio being varied. The heating values of the producer gas are sufficient for stable gas turbine combustion. About 60-70% of the alkali input with fuel was separated from the producer gas in the cyclone. However the total alkali contents of the producer gas was found to be higher than in ABB Stal PFBC gas turbines and at least an order of magnitude higher than what is required by most gas turbine manufacturers for operation of a gas turbine. The carryover particles concentrations in the producer gas were found to be in the range of that for PFBC gas turbines, but higher than what is required by most gas turbine manufacturers for operation of a gas turbine. Samples studied with scanning electronic microscope give indication that most of the carryover particles are below 10{mu}m in size. Fly ash-melting tests have not shown any major ash melting up to 1200{sup o}C, but it was found that some of the particles entrained with producer gas were partially melted. Integrated experiments with a gas turbine need to be done for accurate evaluation of the possibilities to use the producer gas from the gasification of bagasse to run a gas turbine without problems of hard deposits and corrosion on the turbine blades. In part 2 of this two-part paper the results from cane trash gasification tests are reported. (author)

  9. Converting moving-grate incineration from combustion to gasification - numerical simulation of the burning characteristics.

    Science.gov (United States)

    Yang, Yao Bin; Sharifi, Vida N; Swithenbank, Jim

    2007-01-01

    Waste incineration is a politically sensitive issue in the UK. The major current technology is based on direct combustion of wastes in a moving-grate furnace. However, general public opinion prefers non-direct burning technologies. Waste gasification is one of those nearest technologies available. By reducing the primary air-flow rate through the grate of a packed-bed system, operation of the existing solid-waste incineration equipment can be easily converted from combustion mode to gasification mode without major modification of the hardware. The potential advantages of this are lower dust carry-over in the flue gases, lower bed temperature (and therefore lower NO(x) formation in the bed), simplified gas-treatment procedures and lower running cost, among other benefits. The major disadvantages are, however, reduced throughput of the wastes and possibly higher carbon in the ash at exit. In this study, numerical simulation of both combustion and gasification of municipal solid wastes in a full-scale moving grate furnace is carried out employing advanced mathematical models. Burning characteristics, including burning rate, gas composition, temperature and burning efficiency as a function of operating parameters are investigated. Detailed comparisons between the combustion mode and gasification mode are made. The study helps to explore new incineration technology and optimise furnace operating conditions. PMID:16730435

  10. A review on gasification of biomass

    Energy Technology Data Exchange (ETDEWEB)

    Kirubakaran, V. [Rural Technology Centre, Gandhigram Rural University, Gandhigram 624302, Tamil Nadu (India); Sivaramakrishnan, V. [Department of Mechanical Engineering, Saranathan College of Engineering, Tiruchirapalli 620012, Tamil Nadu (India); Nalini, R. [Department of Renewable Energy, Periyar Maniyammai College of Technology for Women, Vallam 613403, Tamil Nadu (India); Sekar, T. [Department of Petrochemical Technology, Anna University, Tiruchirappalli, Tamil Nadu (India); Premalatha, M.; Subramanian, P. [Centre for Energy and Environmental Science and Technology (CEESAT), National Institute of Technology, Tiruchirapalli 620015, Tamil Nadu (India)

    2009-01-15

    Studies on the effect of size, structure, environment, temperature, heating rate, composition of biomass and ash are reviewed. Based on the observations reported so far, auto-gasification of biomass by the bio-oxygen and the catalytic ash would be feasible. The auto-gasification may be explained in terms of heterogeneous catalytic reaction. Better understanding of auto-gasification is possible by further studies carrying out on the effect of heating rate on auto-gasification. (author)

  11. 3rd international conference on coal gasification and liquefaction, University of Pittsburgh

    Energy Technology Data Exchange (ETDEWEB)

    None

    1976-01-01

    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)

  12. Characteristics and utilisation of high-temperature (HTHP) filter dusts from pfb gasification of biomass

    Energy Technology Data Exchange (ETDEWEB)

    Ranta, J. [VTT Energy, Espoo (Finland)

    1996-12-31

    The aim of the study was to survey characteristics, utilisation and possible environmental impacts of solid wastes, i.e., in case of biomass, mainly high-temperature filter ash (HTHP) from pressurised fluidised-bed gasification (PFBG). The aim is to utilise solid wastes (slag, filter dust, additives) from biomass gasification instead of dumping. One alternative is recycling to the soil as liming material or fertiliser. It is expected that the ash recycled to forest soils changes the environment less than non-recycled ash. (orig.) 3 refs.

  13. Survey of biomass gasification. Volume II. Principles of gasification

    Energy Technology Data Exchange (ETDEWEB)

    Reed, T.B. (comp.)

    1979-07-01

    Biomass can be converted by gasification into a clean-burning gaseous fuel that can be used to retrofit existing gas/oil boilers, to power engines, to generate electricity, and as a base for synthesis of methanol, gasoline, ammonia, or methane. This survey describes biomass gasification, associated technologies, and issues in three volumes. Volume I contains the synopsis and executive summary, giving highlights of the findings of the other volumes. In Volume II the technical background necessary for understanding the science, engineering, and commercialization of biomass is presented. In Volume III the present status of gasification processes is described in detail, followed by chapters on economics, gas conditioning, fuel synthesis, the institutional role to be played by the federal government, and recommendations for future research and development.

  14. Diesel power plants based on biomass gasification; Biomassan ja turpeen kaasutukseen perustuvien dieselvoimalaitosten toteutettavuustutkimus

    Energy Technology Data Exchange (ETDEWEB)

    Kurkela, E.; Staahlberg, P.; Solantausta, Y.; Wilen, C.

    1995-12-31

    Different power production systems have been developed for biomass feedstocks. However, only few of these systems can meet the following three requirements: (a) suitability to small scale electricity production (< 5-10 MWe), (b) reliable operation with realistically available biomass feedstocks, and (c) potential for economical competitiveness. The fluidized-bed boilers have been successfully operated with wood waste and peat down to outputs of the order of 5 MWe and the investment costs have been successfully lowered to a reasonable level. However, this concept is most suitable for combined heat and electricity production and smaller plant sizes are not considered feasible. One of the most promising alternative for this commercially proven technology is the diesel power plant based on gasification. This concept has a potential for higher power to heat ratios in cogeneration or higher efficiency in separate electricity production. The objectives of this project were (a) to evaluate the technical and economical feasibility of diesel power plants based on biomass gasification and (b) to study the effects of operating conditions (temperature, bed material and air staging) on the performance of a circulating fluidized-bed gasifier. The experimental part of the project was carried out on a new PDU-scale Circulating Fluidized-Bed Gasification test facility of VTT. Wood residues were used as the feedstocks and the experiments were mainly focused on tar formation and gasifier performance. The results will be compared to earlier VTT data obtained for bubbling-bed reactors. The techno-economic feasibility studies are carried out using existing process modelling tools of VTT and the gasification based diesel plants will be compared to conventional fluidized-bed boilers

  15. Diesel power plants based on biomass gasification; Biomassan ja turpeen kaasutukseen perustuen dieselvoimalaitosten toteutettavuustutkimus

    Energy Technology Data Exchange (ETDEWEB)

    Kurkela, E.; Staahlberg, P.; Solantausta, Y. [VTT Energy, Espoo (Finland)

    1996-12-01

    Different power production systems have been developed for biomass feedstocks. However, only few of these systems can meet the following three requirements: (1) suitability to small scale electricity production (<5-10 MWe), (2) reliable operation with realistically available biomass feedstocks, and (3) potential for economical competitiveness. The fluidized-bed boilers have been successfully operated with wood waste and peat down to outputs of the order of 5 MWe and the investment costs have been successfully lowered to a reasonable level. However, this concept is most suitable for combined heat and electricity production and smaller plant sizes are not considered feasible. One of the most promising alternative for this commercially proven technology is the diesel power plant based on gasification. This concept has a potential for higher power to heat ratios in cogeneration or higher efficiency in separate electricity production. The objectives of this project were (1) to evaluate the technical and economical feasibility of diesel power plants based on biomass gasification and (2) to study the effects of operating conditions (temperature, bed material and air staging) on the performance of a circulating fluidized-bed gasifier. The experimental part of the project was carried out on a new PDU-scale Circulating Fluidized-Bed Gasification test facility of VTT. Wood residues were used as the feedstocks and the experiments were mainly focused on tar formation and gasifier performance. The results will be compared to earlier VTT data obtained for bubbling-bed reactors. The techno-economic feasibility studies are carried out using existing process modelling tools of VTT and the gasification based diesel plants will be compared to conventional fluidized-bed boilers. The studies are scheduled to be completed in March 1996. (author)

  16. Diesel power plants based on biomass gasification. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kurkela, E.; Staahlberg, P.; Solantausta, Y.; Wilen, C.

    1996-12-31

    The aim of the project was to assess the competitiveness and market potential of small-scale power plant concepts based on biomass gasification and on diesel/gas engines, and to study the effect of process parameters on the efficiency of the circulating fluidized-bed gasifier and on the formation of tarry impurities. Alternative diesel/gas engine power plant concepts based on gasification in scale 6-50 MW{sub e} were assessed. In the basic version, where the electricity is generated only by the a diesel/gas engine, the efficiency level of 37 % is achieved in power generation. When steam cycle is added to the process the efficiency of power generation increases to 44-48 %. The efficiencies achieved in the process are very high compared with those of biomass power plant processes on a commercial level or under development. The most significant potential of biomass-based power generation is made up by wastes of sugar industries in south and Central America and in Asia. There are also very extensive growth potentials of bioenergy use in the NAFTA countries (USA, Canada and Mexico) and in Europe. In Europe, the bioenergy use is expected to grow most sharply in Italy, Spain, Germany and Poland. Carbon conversion obtained in the gasifier was in the range of 99.0-99.9 % for sawdust and 96-98 % for forest residue chips. The tar content of the product gas 10-15 g/m- m{sup 3}{sub n}, for sawdust in the gasification temperature of 830-930 deg C and with sand as circulating fluid-bed. When dolomite was used as circulating fluid-bed, the tar contents were 2-3 g/m{sup 3}{sub n} at as low temperatures as 880-890 deg C. The tar content of gas can be reduced sharply by phasing of gasification air and by using catalytic circulating fluid-bed material Bioenergy Research Programme; LIEKKI 2 Research Programme. 26 refs., 40 figs.

  17. The assessment of sewage sludge gasification by-products toxicity by ecotoxicologial test.

    Science.gov (United States)

    Werle, Sebastian; Dudziak, Mariusz

    2015-08-01

    The process of gasification of sewage sludge generates by-products, which may be contaminated with toxic and hazardous substances, both organic and inorganic. It is therefore important to assess the environmental risk associated with this type of waste. The feasibility of using an ecotoxicological tests for this purpose was determined in the presented study. The applied tests contained indicator organisms belonging to various biological groups (bacteria, crustaceans, plants). The subject of the study were solid (ash, char) and liquid (tar) by-products generated during gasification (in a fixed bed reactor) of dried sewage sludge from various wastewater treatment systems. The tested samples were classified based on their toxic effect. The sensitivity of the indicator organisms to the tested material was determined. In-house procedures for the preparation for toxicity analysis of both sewage sludge and by-products generated during the gasification were presented. The scope of work also included the determination of the effect of selected process parameters (temperature, amount of gasifying agent) on the toxicity of gasification by-products depending on the sewage sludge source. It was shown that both the type of sewage sludge and the parameters of the gasification process affects the toxicity of the by-products of gasification. However, the results of toxicity studies also depend on the type of ecotoxicological test used, which is associated with a different sensitivity of the indicator organisms. Nevertheless, it may be concluded that the by-products formed during the gasification of the low toxicity sewage sludge can be regarded as non-toxic or low toxic. However, the results analysis of the gasification of the toxic sludge were not conclusive, which leads to further research needs in this area. PMID:25827844

  18. Coal gasification: A multiple talent

    Energy Technology Data Exchange (ETDEWEB)

    Schreurs, H.

    1996-12-31

    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.

  19. Historical development of underground coal gasification

    Energy Technology Data Exchange (ETDEWEB)

    Olness, D.; Gregg, D.W.

    1977-06-30

    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.

  20. Environmental benefits of underground coal gasification.

    Science.gov (United States)

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

    2002-04-01

    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

  1. History, challenge and solution of biomass gasification: a review%生物质气化技术的再认识

    Institute of Scientific and Technical Information of China (English)

    张齐生; 马中青; 周建斌

    2013-01-01

    Recently, as the widely application of biotechnology in the industry, agriculture and energy, it has been playing a great role in technology reform and economy growth. And currently, due to the problems of rapid depletion of fossil fuel and environmental pollution, people are looking for a renewable and green fuel and fuel processing technology that can partially replace the fossil fuel. Biomass gasification technology, regarding as a renewable and sustainable bio-energy conversion technology, has been developing rapidly. However, for the immature gasification system and ineffective recycling utilization of gasification byproducts (bio-char and bio-extract) , it hinders the commercialization and operation of gasification technology seriously. Biomass gasification poly-generation technology is defined as the comprehensive utilization of gas (producer gas) , solid (bio-char) and liquid (bio-extract) products from biomass downdraft fixed bed gasification system. The presentation of poly-generation methodology and the successful application of the associated e-quipment provide a new guideline for the further development of biomass gasification technology. This paper describes the history, challenge and solution of biomass gasification technology.%近现代,生物技术在工业、农业和能源领域得到广泛应用,对世界科技和经济发展起到重大的变革和促进作用.由于化石燃料资源性枯竭问题和环境污染问题,寻找一种清洁、可再生的替代燃料和燃料生产技术已迫在眉睫.生物质气化技术作为一种清洁的可再生能源利用技术得到了快速发展,然而由于气化设备自身不够成熟以及未对气化副产物(生物质炭和生物质提取液)加以有效利用等问题,严重阻碍了生物质气化技术的商业化推广和运行.生物质气化多联产技术是指基于生物质下吸式固定床气化的气、固、液三相产品多联产及其产品分相回收、利用技术.

  2. Pilot plant apparatus for pressurized fluidized bed combustion and gasification

    Czech Academy of Sciences Publication Activity Database

    Svoboda, Karel; Hartman, Miloslav; Čermák, Jiří

    Praha, 1999, s. 89-90. [International Conference on the Ecological Use of Coal in the Energy Sector "Clean Coal 2000". Praha (CZ), 31.05.1999-03.06.1999] Grant ostatní: INCO-COPERNICUS(XE) IC15-CT98-0513 Subject RIV: DI - Air Pollution ; Quality

  3. The shell coal gasification process

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-12-01

    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.

  4. From waste to energy -- Catalytic steam gasification of broiler litter

    Energy Technology Data Exchange (ETDEWEB)

    Jones, J.A.; Sheth, A.C.

    1999-07-01

    In 1996, the production of broiler chickens in the US was approximately 7.60 billion head. The quantity of litter generated is enormous. In 1992, the Southeast region alone produced over five million tons of broiler litter. The litter removed from the broiler houses is rich in nutrients and often spread over land as a fertilizer. Without careful management, the associated agricultural runoff can cause severe environmental damage. With increasing broiler litter production, the implementation of alternative disposal technologies is essential to the sustainable development of the poultry industry. A process originally developed for the conversion of coals to clean gaseous fuel may provide an answer. Catalytic steam gasification utilities an alkali salt catalyst and steam to convert a carbonaceous feedstock to a gas mixture composed primarily of carbon monoxide, carbon dioxide, hydrogen, and methane. The low to medium energy content gas produced may be utilized as an energy source or chemical feedstock. Broiler litter is an attractive candidate for catalytic steam gasification due to its high potassium content. Experiments conducted in UTSI's bench-scale high-pressure fixed bed gasifier have provided data for technical and economic feasibility studies of the process. Experiments have also been performed to examine the effects of temperature, pressure, and additional catalysts on the gasification rate.

  5. Pyrolysis pretreatment of biomass for entrained-flow gasification

    International Nuclear Information System (INIS)

    The biomass for entrained-flow gasification needs to be pretreated to significantly increase its heating value and to make it more readily transportable. The pyrolysis pretreatment was conducted in a lab scale fixed-bed reactor; the reactor was heated to elevate the temperature at 5 °C/min before holding at the desired pyrolysis temperature for 1.5 h a fixed time. The effects of pyrolysis temperature on the yield, composition and heating value of the gaseous, liquid and solid products were determined. The pyrolysis removed most oxygenated constituents of rice straw while significantly increased its energy density. Meantime, it changes the physical properties of biomass powders. The results show that the angle of repose, the angle of internal friction of semi-char decrease obviously; the bulk density of semi-char is bigger than that of biomass. This could favor the feeding of biomass. Considering yield and heating value of the solid semi-char product and the feeding problem, the best pyrolysis temperature was 400 °C. The results of this study have confirmed the feasibility of employing pyrolyzed biomass for entrained-flow gasification; they are useful for the additional studies that will be necessary for designing an efficient biomass entrained-flow gasification system.

  6. UTILIZATION OF LIGHTWEIGHT MATERIALS MADE FROM COAL GASIFICATION SLAGS

    Energy Technology Data Exchange (ETDEWEB)

    Vas Choudhry; Stephen Kwan; Steven R. Hadley

    2001-07-01

    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.

  7. Gasification of biomass for energy production. State of technology in Finland and global market perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Wilen, C.; Kurkela, E. [VTT Energy, Espoo (Finland). Energy Production Technologies

    1997-12-31

    This report reviews the development of the biomass gasification technology in Finland over the last two decades. Information on Finnish biomass resources and use, energy economy and national research policy is provided as background. Global biomass resources and potential energy from biomass markets are also assessed based on available literature, to put the development of the gasification technology into a wider perspective of global biomass utilization for energy production. The increasing use of biomass and other indigenous forms of energy has been part and parcel of the Finnish energy policy for some twenty years. Biomass and peat account for almost 20% of the production of primary energy in Finland. As the consumption of biofuels is significantly lower than the annual growth or renewal, the use of bioenergy is considered to be an important measure of reducing carbon dioxide emissions. Research and development on thermal gasification of solid fuels was initiated in the late 1970s in Finland. The principal aim was to decrease the dependence of Finnish energy economy on imported oil by increasing the utilization potential of indigenous fuels. Development in the early 1980s focused on simple atmospheric-pressure fuel gas applications including a gasification heating plant. Eight Bioneer updraft gasifiers (abt 5 MW{sub th}) were constructed in 1982-1986, and a new Bioneer gasifier was commissioned in eastern Finland in 1996. A Pyroflow circulating fluidised-bed gasifies was also commercialized in the mid-1980s; four gasifiers (15-35 MW{sub th}) were commissioned. In the late 1980s the interest in integrated gasification combined-cycle (IGCC) power plants, based on pressurised air gasification of biomass and hot gas cleanup, increased in Finland and in many other countries. The utilization potential for indigenous fuels is mainly in medium-scale combined heat and electricity production (20-150 MW,). Foster Wheeler Energia Oy, Carbona Inc. and Imatran Voima Oy are

  8. Gasification of biomass for energy production. State of technology in Finland and global market perspectives

    International Nuclear Information System (INIS)

    This report reviews the development of the biomass gasification technology in Finland over the last two decades. Information on Finnish biomass resources and use, energy economy and national research policy is provided as background. Global biomass resources and potential energy from biomass markets are also assessed based on available literature, to put the development of the gasification technology into a wider perspective of global biomass utilization for energy production. The increasing use of biomass and other indigenous forms of energy has been part and parcel of the Finnish energy policy for some twenty years. Biomass and peat account for almost 20% of the production of primary energy in Finland. As the consumption of biofuels is significantly lower than the annual growth or renewal, the use of bioenergy is considered to be an important measure of reducing carbon dioxide emissions. Research and development on thermal gasification of solid fuels was initiated in the late 1970s in Finland. The principal aim was to decrease the dependence of Finnish energy economy on imported oil by increasing the utilization potential of indigenous fuels. Development in the early 1980s focused on simple atmospheric-pressure fuel gas applications including a gasification heating plant. Eight Bioneer updraft gasifiers (abt 5 MWth) were constructed in 1982-1986, and a new Bioneer gasifier was commissioned in eastern Finland in 1996. A Pyroflow circulating fluidised-bed gasifies was also commercialized in the mid-1980s; four gasifiers (15-35 MWth) were commissioned. In the late 1980s the interest in integrated gasification combined-cycle (IGCC) power plants, based on pressurised air gasification of biomass and hot gas cleanup, increased in Finland and in many other countries. The utilization potential for indigenous fuels is mainly in medium-scale combined heat and electricity production (20-150 MW,). Foster Wheeler Energia Oy, Carbona Inc. and Imatran Voima Oy are the main

  9. Workshop proceedings: profit from gasification

    Energy Technology Data Exchange (ETDEWEB)

    Williams, B.C. [University of Ulster, Coleraine (United Kingdom). NICERT

    2000-08-01

    The report summarises an introductory talk given by Richard Tubberer of PowerGen and then presents summaries of presentations to each of four sessions followed by reports of syndicate discussions and the results presented by the spokepersons from the syndicates. Piet Zuidevelt of Shell gave a presentation on 'Environmental drivers' behind gasification; Philip Veale of Aon Group talked on insuring projects through development and operational phases; Shane Woodroofe, Price Waterhouse Coopers, gave a presentation on the bankability and commercial framework aspects of electricity from gasification and OV Daslav Brkiv from ABB Lummus Global gave a talk on the 'Plus factor' in IGCC projects.

  10. Gasification of coal to produce hydrogen

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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)

  12. Plasma gasification process: Modeling, simulation and comparison with conventional air gasification

    International Nuclear Information System (INIS)

    Highlights: ► Plasma/conventional gasification are modeled via Gibbs energy minimization. ► The model is applied to wide range of feedstock, tire, biomass, coal, oil shale. ► Plasma gasification show high efficiency for tire waste and coal. ► Efficiency is around 42% for plasma and 72% for conventional gasification. ► Lower plasma gasification efficiency justifies hazardous waste energy recovery. - Abstract: In this study, two methods of gasification are developed for the gasification of various feedstock, these are plasma gasification and conventional air gasification. The two methods are based on non-stoichiometric Gibbs energy minimization approach. The model takes into account the different type of feedstocks, which are analyzed at waste to energy lab at Masdar Institute, oxidizer used along with the plasma energy input and accurately evaluates the syngas composition. The developed model is applied for several types of feedstock, i.e. waste tire material, coal, plywood, pine needles, oil shale, and municipal solid waste (MSW), algae, treated/untreated wood, instigating air/steam as the plasma gas and only air as oxidizer for conventional gasification. The results of plasma gasification and conventional air gasification are calculated on the bases of product gas composition and the process efficiency. Results of plasma gasification shows that high gasification efficiency is achievable using both tire waste material and coal, also, the second law efficiency is calculated for plasma gasification that shows a relative high efficiency for tire and coal as compare to other feedstock. The average process efficiency for plasma gasification is calculated to be around 42%. On other hand the result of conventional gasification shows an average efficiency of 72%. The low efficiency of plasma gasification suggest that if only the disposal of hazard waste material is considered then plasma gasification can be a viable option to recover energy.

  13. Biomass waste gasification - can be the two stage process suitable for tar reduction and power generation?

    Science.gov (United States)

    Sulc, Jindřich; Stojdl, Jiří; Richter, Miroslav; Popelka, Jan; Svoboda, Karel; Smetana, Jiří; Vacek, Jiří; Skoblja, Siarhei; Buryan, Petr

    2012-04-01

    A pilot scale gasification unit with novel co-current, updraft arrangement in the first stage and counter-current downdraft in the second stage was developed and exploited for studying effects of two stage gasification in comparison with one stage gasification of biomass (wood pellets) on fuel gas composition and attainable gas purity. Significant producer gas parameters (gas composition, heating value, content of tar compounds, content of inorganic gas impurities) were compared for the two stage and the one stage method of the gasification arrangement with only the upward moving bed (co-current updraft). The main novel features of the gasifier conception include grate-less reactor, upward moving bed of biomass particles (e.g. pellets) by means of a screw elevator with changeable rotational speed and gradual expanding diameter of the cylindrical reactor in the part above the upper end of the screw. The gasifier concept and arrangement are considered convenient for thermal power range 100-350 kW(th). The second stage of the gasifier served mainly for tar compounds destruction/reforming by increased temperature (around 950°C) and for gasification reaction of the fuel gas with char. The second stage used additional combustion of the fuel gas by preheated secondary air for attaining higher temperature and faster gasification of the remaining char from the first stage. The measurements of gas composition and tar compound contents confirmed superiority of the two stage gasification system, drastic decrease of aromatic compounds with two and higher number of benzene rings by 1-2 orders. On the other hand the two stage gasification (with overall ER=0.71) led to substantial reduction of gas heating value (LHV=3.15 MJ/Nm(3)), elevation of gas volume and increase of nitrogen content in fuel gas. The increased temperature (>950°C) at the entrance to the char bed caused also substantial decrease of ammonia content in fuel gas. The char with higher content of ash leaving the

  14. Modeling particle population balances in fluidized-bed wood gasifiers

    International Nuclear Information System (INIS)

    An unsteady model is developed for the particle size distribution in fluidized-bed reactors including fragmentation, abrasion, elutriation and the chemical reactions of wood gasification. Based on the assumption of constant conditions (gas composition, temperature, velocity) of the surrounding atmosphere, an analytical solution is developed for the distribution of sizes belonging to the classes of mother and fine particles. It is found that for the typical feed sizes (minimum above 3 × 10−2 mm) and the usual maximum size of fine particles (2.4 × 10−3 mm), the behavior of fine particles is quasi-steady with respect to mother particles. The numerical solution of the quasi-steady formulation of particle population balances is also coupled with a two-phase (bubble and emulsion), three-zone (bed, splash zone and freeboard) model for a bubbling fluidized-bed reactor, giving predictions of the producer gas composition in agreement with measurements for air gasification of wood. - Highlights: • Particle size distribution in fluidized-bed gasifiers is modeled. • Fragmentation, abrasion, elutriation and the chemical reactions of wood gasification are described. • A quasi-steady behavior of the fine particles with respect to mother particles is found. • The particle size distribution model is coupled with a transport model for a bubbling fluidized bed. • Good agreement is obtained between measurements and predictions for highly variable operating conditions

  15. 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

    OpenAIRE

    Van Dyk, Johannes Chrisstoffel

    2006-01-01

    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...

  16. Hydrogen production from palm kernel shell via integrated catalytic adsorption (ICA) steam gasification

    International Nuclear Information System (INIS)

    Highlights: • The paper presents integrated catalytic adsorption (ICA) steam gasification for H2 yield. • Effects of adsorbent to biomass, biomass particle size and fluidization velocity on H2 yield are examined. • The present study produces higher H2 yield as compared to that obtained in literatures. • The ICA provides enhancement of H2 yield as compared to independent catalytic and CO2 adsorption gasification systems. - Abstract: The present study investigates the integrated catalytic adsorption (ICA) steam gasification of palm kernel shell for hydrogen production in a pilot scale atmospheric fluidized bed gasifier. The biomass steam gasification is performed in the presence of an adsorbent and a catalyst in the system. The effect of adsorbent to biomass (A/B) ratio (0.5–1.5 wt/wt), fluidization velocity (0.15–0.26 m/s) and biomass particle size (0.355–2.0 mm) are studied at temperature of 675 °C, steam to biomass (S/B) ratio of 2.0 (wt/wt) and biomass to catalyst ratio of 0.1 (wt/wt). Hydrogen composition and yield, total gas yield, and lower product gas heating values (LHVgas) increases with increasing A/B ratio, while particle size has no significant effect on hydrogen composition and yield, total gas and char yield, gasification and carbon conversion efficiency. However, gas heating values increased with increasing biomass particle size which is due to presence of high methane content in product gas. Meanwhile, medium fluidization velocity of 0.21 m/s favoured hydrogen composition and yield. The results showed that the maximum hydrogen composition and yield of 84.62 vol% and 91.11 g H2/kg biomass are observed at A/B ratio of 1.5, S/B ratio of 2.0, catalyst to biomass ratio of 0.1 and temperature of 675 °C. The product gas heating values are observed in the range of 10.92–17.02 MJ/N m3. Gasification and carbon conversion efficiency are observed in the range of 25.66–42.95% and 20.61–41.95%, respectively. These lower efficiencies are due

  17. Biomass gasification in the Netherlands

    Energy Technology Data Exchange (ETDEWEB)

    Van der Drift, A. [ECN Biomass and Energy Efficiency, Petten (Netherlands)

    2013-07-15

    This reports summarizes the activities, industries, and plants on biomass gasification in the Netherlands. Most of the initiatives somehow relate to waste streams, rather than clean biomass, which may seem logic for a densely populated country as the Netherlands. Furthermore, there is an increasing interest for the production of SNG (Substitute Natural Gas) from biomass, both from governments and industry.

  18. The Shell coal gasification process

    International Nuclear Information System (INIS)

    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

  19. Energetic recovery from LNG gasification plant : cold energy utilization in agro-alimentary industry

    International Nuclear Information System (INIS)

    It is known how the complete gasification of liquefied natural gas (LNG) can return about 230 kWh/t of energy. Nevertheless out of 51 gasification plants in the world, only 31 of them are equipped with systems for the partial recovery of the available energy. At the moment most of these plants mainly produce electric energy; however the employment of the cold energy results very interesting, in fact, it can be recovered for agrofood transformation and conservation as well as for some loops in the cold chain. Cold energy at low temperatures requires high amounts of mechanical energy and it unavoidably increases as the required temperature diminishes. Cold energy recovery from LNG gasification would allow considerable energy and economic savings to these applications, as well as environmental benefits due to the reduction of climate-changing gas emissions. The task of this work is to assess the possibility to create around a gasification plant an industrial site for firms working on the transformation and conservation of agrofood products locally grown. The cold recovered from gasification would be distributed to those firms through an opportune liquid Co2 network distribution capable of supplying the cold to the different facilities. A LNG gasification plant in a highly agricultural zone in Sicily would increase the worth of the agrofood production, lower transformation and conservation costs when compared to the traditional systems and bring economic and environmental benefits to the interested areas.

  20. Multicriteria Optimization of Gasification Operational Parameters Using a Pareto Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Miguel Caldas

    2005-04-01

    Full Text Available Gasification is a well-known technology that allows for a combustible gas to be obtained from a carbonaceous fuel by a partial oxidation process (POX. The resulting gas (synthesis gas or syngas can be used either as a fuel or as a feedstock for chemical production. Recently, gasification has also received a great deal of attention concerning power production possibilities through IGCC process (Integrated Gasification Combined Cycle, which is currently the most environmentally friendly and efficient method for the production of electricity. Gasification allows for low grade fuels, or dirty fuels, to be used in an environmental acceptable way. Amongst these fuels are wastes from the petrochemical and other industries, which vary in composition from shipment to shipment, and from lot to lot. If operating conditions are kept constant this could result in lose of efficiency. This paper presents an application of Genetic Algorithms to optimize the operating parameters of a gasifier processing a given fuel, so that the system achieves maximum efficiency for each particular fuel composition. A Pareto multiobjective optimization method, combined with a Genetic Algorithm, is applied to the simultaneous maximization of two different objective functions: Cold Gas Efficiency and Hydrogen Contents of the syngas. Results show that the optimization method developed is fast and simple enough to be used for on-line adjustment of the gasification operating parameters for each fuel composition and aim of gasification, thus improving overall performance of the industrial process.

  1. Circulating fluidized-bed technologies for the conversion of biomass into energy

    International Nuclear Information System (INIS)

    The paper introduces circulating fluidized-bed (CFB) combustion and CFB gasification. CFB combustion units are state-of-the-art and have proven their ability to convert biomass into power and/or steam. The existing units and projects in developing countries are discussed as examples of conventional technology. To illustrate advanced technologies, CFB gasification is discussed. Important process parameters of plants already in operation or under construction in developed countries are shown, Criteria for the selection of CFB combustion or gasification based on available feedstocks and products required are discussed. Finally, a procedure for implementing Lurgi's CFB technology in developing countries is proposed. (author)

  2. Challenges for implementation of bioenergy in the Brazilian energy matrix and biomass gasification process for the production of electrical power; Desafios da bioenergia para sua implementacao na matriz energetica brasileira e o processo de gaseificacao da biomassa para a producao de energia eletrica

    Energy Technology Data Exchange (ETDEWEB)

    Figueiroa, E.O.; Moutinho-Junior, D.A.A.; Silva, J.D. [Universidade de Pernambuco (UPE), Recife, PE (Brazil)

    2010-07-01

    The gasification is the conversion of any solid or liquid fuel in fuel gas through the process of the partial oxidation at a high temperature. The gasification process of course occurs in four distinct physicochemical stages with different temperatures of reaction, as drying of the biomass, pyrolysis, reduction and combustion. The reorganization of the Brazilian electric sector foresees technological innovations in the system of electric generation for the country. The process of gasification integrated in a combined cycle (cycle of Brayton and cycle of Rankine) characterizes an innovative technology. It is with noting that this technology is still in improvement, it shows an excellent perspective of commercial viability and efficiency significantly higher than conventional technology. This work presents a study of the gases generated in the zone of combustion and its behavior in the zone of 'freeboard' of a gasifier of fluidized stream bed. For this study, we made the use of one hybrid technique (half-analytical) that is the transformed one of Fourier. (author)

  3. The production of synthetic natural gas (SNG): A comparison of three wood gasification systems for energy balance and overall efficiency

    International Nuclear Information System (INIS)

    The production of Synthetic Natural Gas from biomass (Bio-SNG) by gasification and upgrading of the gas is an attractive option to reduce CO2 emissions and replace declining fossil natural gas reserves. Production of energy from biomass is approximately CO2 neutral. Production of Bio-SNG can even be CO2 negative, since in the final upgrading step, part of the biomass carbon is removed as CO2, which can be stored. The use of biomass for CO2 reduction will increase the biomass demand and therefore will increase the price of biomass. Consequently, a high overall efficiency is a prerequisite for any biomass conversion process. Various biomass gasification technologies are suitable to produce SNG. The present article contains an analysis of the Bio-SNG process efficiency that can be obtained using three different gasification technologies and associated gas cleaning and methanation equipment. These technologies are: (1) Entrained Flow, (2) Circulating Fluidized Bed and (3) Allothermal or Indirect gasification. The aim of this work is to identify the gasification route with the highest process efficiency from biomass to SNG and to quantify the differences in overall efficiency. Aspen Plus registered was used as modeling tool. The heat and mass balances are based on experimental data from literature and our own experience. Overall efficiency to SNG is highest for Allothermal gasification. The net overall efficiencies on LHV basis, including electricity consumption and pre-treatment but excluding transport of biomass are 54% for Entrained Flow, 58% for CFB and 67% for Allothermal gasification. Because of the significantly higher efficiency to SNG for the route via Allothermal gasification, ECN is working on the further development of Allothermal gasification. ECN has built and tested a 30 kWth lab scale gasifier connected to a gas cleaning test rig and methanation unit and presently is building a 0.8 MWth pilot plant, called Milena, which will be connected to the existing

  4. Gasification biochar as a valuable by-product for carbon sequestration and soil amendment

    International Nuclear Information System (INIS)

    Thermal gasification of various biomass residues is a promising technology for combining bioenergy production with soil fertility management through the application of the resulting biochar as soil amendment. In this study, we investigated gasification biochar (GB) materials originating from two major global biomass fuels: straw gasification biochar (SGB) and wood gasification biochar (WGB), produced by a Low Temperature Circulating Fluidized Bed gasifier (LT-CFB) and a TwoStage gasifier, respectively, optimized for energy conversion. Stability of carbon in GB against microbial degradation was assessed in a short-term soil incubation study and compared to the traditional practice of direct incorporation of cereal straw. The GBs were chemically and physically characterized to evaluate their potential to improve soil quality parameters. After 110 days of incubation, about 3% of the added GB carbon was respired as CO2, compared to 80% of the straw carbon added. The stability of GB was also confirmed by low H/C and O/C atomic ratios with lowest values for WGB (H/C 0.12 and O/C 0.10). The soil application of GBs exhibited a liming effect increasing the soil pH from ca 8 to 9. Results from scanning electron microscopy and BET analyses showed high porosity and specific surface area of both GBs, indicating a high potential to increase important soil quality parameters such as soil structure, nutrient and water retention, especially for WGB. These results seem promising regarding the possibility to combine an efficient bioenergy production with various soil aspects such as carbon sequestration and soil quality improvements. - Highlights: • Biomass gasification can combine efficient bioenergy production with valuable biochar residuals for soil improvements. • The two investigated gasification biochars are recalcitrant indicating soil carbon sequestration potential. • Gasification biochars are potential soil improvers due to high specific surface area, liming effect and

  5. Reduction of tars by dolomite cracking during two-stage gasification of olive cake

    International Nuclear Information System (INIS)

    The effective implementation of biomass gasification has to overcome some difficulties such as the minimization of tars. On the other hand, with a proper design of experimental conditions, biomass gasification can be directed towards the production of hydrogen. The aim of the present study was to investigate the use of dolomite as catalyst to improve tar removal and hydrogen production by a two-stage steam gasification process, using olive cake as raw material. Fixing the olive cake gasification conditions on the first reactor (900 oC, steam flow rate of 190 mg min-1, O2 flow rate of 7.5 cm3 min-1), the cracking of tars was prompted by: a) steam gasification (steam flow rate in the range 40-190 mg min-1) at 1000 oC, b) catalytic gasification, using dolomite (5% wt.). It was found that increasing steam flow rate up to 110 mg min-1 involves an increase in hydrogen fraction due to the enhancement of water gas and water gas shift reactions. Also, the influence of dolomite was studied at 800 and 900 oC in a second reactor, finding better results at 800 oC, which gave an hydrogen fraction of 0.51. -- Highlights: → The use of dolomite for tar cracking during olive cake steam gasification was studied. → Two reactors in series were used, and the second one was provided with a dolomite bed. → Increasing the steam flow rate above 40mg min-1 in reactor 2, favours H2 production. → Using dolomite promotes tar cracking increasing H2 production, especially at 800 oC.

  6. Nuclear process heat - application to coal gasification

    International Nuclear Information System (INIS)

    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.)

  7. Co-gasification of pelletized wood residues

    Energy Technology Data Exchange (ETDEWEB)

    Carlos A. Alzate; Farid Chejne; Carlos F. Valdes; Arturo Berrio; Javier De La Cruz; Carlos A. Londono [Universidad Nacional de Colombia, Antioquia (Colombia). Grupo de Termodinamica Aplicada y Energias Alternativas

    2009-03-15

    A pelletization process was designed which produces cylindrical pellets 8 mm in length and 4 mm in diameter. These ones were manufactured using a blend of Pinus Patula and Cypress sawdust and coal in proportions of 0%, 5%, 10%, 20%, and 30% v/v of coal of rank sub-bituminous extracted from the Nech mine (Amaga-Antioquia). For this procedure, sodium carboxymethyl cellulose (CMC) was used as binder at three different concentrations. The co-gasification experiments were carried out with two kinds of mixtures, the first one was composed of granular coal and pellets of 100% wood and the second one was composed of pulverized wood and granular coal pellets. All samples were co-gasified with steam by using an electrical heated fluidized-bed reactor, operating in batches, at 850{sup o}C. The main components of the gaseous product were H{sub 2}, CO, CO{sub 2}, CH{sub 4}, and N{sub 2} with approximate quantities of 59%, 6.0%, 20%, 5.0%, and 9.0% v/v, respectively, and the higher heating values ranged from between 7.1 and 9.5 MJ/Nm{sup 3}.

  8. Study of the Apparent Kinetics of Biomass Gasification Using High-Temperature Steam

    Energy Technology Data Exchange (ETDEWEB)

    Alevanau, Aliaksandr

    2010-10-15

    Among the latest achievements in gasification technology, one may list the development of a method to preheat gasification agents using switched ceramic honey combs. The best output from this technology is achieved with use of water steam as a gasification agent, which is heated up to 1600 deg C. The application of these temperatures with steam as a gasification agent provides a cleaner syngas (no nitrogen from air, cracked tars) and the ash melts into easily utilised glass-like sludge. High hydrogen content in output gas is also favourable for end-user applications.Among the other advantages of this technology is the presumable application of fixed-bed-type reactors fed by separately produced and preheated steam. This construction assumes relatively high steam flow rates to deliver the heat needed for endothermic reactions involving biomass. The biomass is to be heated uniformly and evenly in the volume of the whole reactor, providing easier and simpler control and operation in comparison to other types of reactors. To provide potential constructors and exploiters of these reactors with the kinetic data needed for the calculations of vital parameters for both reactor construction and exploitation, basic experimental research of high-temperature steam gasification of four types of industrially produced biomass has been conducted.Kinetic data have been obtained for straw and wood pellets, wood-chip charcoal and compressed charcoal of mixed origin

  9. Comparative evaluation of kinetic, equilibrium and semi-equilibrium models for biomass gasification

    Energy Technology Data Exchange (ETDEWEB)

    Buragohain, Buljit [Center for Energy, Indian Institute of Technology Guwahati, Guwahati – 781 039, Assam (India); Chakma, Sankar; Kumar, Peeush [Department of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati – 781 039, Assam (India); Mahanta, Pinakeswar [Center for Energy, Indian Institute of Technology Guwahati, Guwahati – 781 039, Assam (India); Department of Mechanical Engineering, Indian Institute of Technology Guwahati, Guwahati – 781 039, Assam (India); Moholkar, Vijayanand S. [Center for Energy, Indian Institute of Technology Guwahati, Guwahati – 781 039, Assam (India); Department of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati – 781 039, Assam (India)

    2013-07-01

    Modeling of biomass gasification has been an active area of research for past two decades. In the published literature, three approaches have been adopted for the modeling of this process, viz. thermodynamic equilibrium, semi-equilibrium and kinetic. In this paper, we have attempted to present a comparative assessment of these three types of models for predicting outcome of the gasification process in a circulating fluidized bed gasifier. Two model biomass, viz. rice husk and wood particles, have been chosen for analysis, with gasification medium being air. Although the trends in molar composition, net yield and LHV of the producer gas predicted by three models are in concurrence, significant quantitative difference is seen in the results. Due to rather slow kinetics of char gasification and tar oxidation, carbon conversion achieved in single pass of biomass through the gasifier, calculated using kinetic model, is quite low, which adversely affects the yield and LHV of the producer gas. Although equilibrium and semi-equilibrium models reveal relative insensitivity of producer gas characteristics towards temperature, the kinetic model shows significant effect of temperature on LHV of the gas at low air ratios. Kinetic models also reveal volume of the gasifier to be an insignificant parameter, as the net yield and LHV of the gas resulting from 6 m and 10 m riser is same. On a whole, the analysis presented in this paper indicates that thermodynamic models are useful tools for quantitative assessment of the gasification process, while kinetic models provide physically more realistic picture.

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

    Energy Technology Data Exchange (ETDEWEB)

    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

    2016-01-01

    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.

  11. Hydrogen production from biomass gasification using biochar as a catalyst/support.

    Science.gov (United States)

    Yao, Dingding; Hu, Qiang; Wang, Daqian; Yang, Haiping; Wu, Chunfei; Wang, Xianhua; Chen, Hanping

    2016-09-01

    Biochar is a promising catalyst/support for biomass gasification. Hydrogen production from biomass steam gasification with biochar or Ni-based biochar has been investigated using a two stage fixed bed reactor. Commercial activated carbon was also studied as a comparison. Catalyst was prepared with an impregnation method and characterized by X-ray diffraction, specific surface and porosity analysis, X-ray fluorescence and scanning electron micrograph. The effects of gasification temperature, steam to biomass ratio, Ni loading and bio-char properties on catalyst activity in terms of hydrogen production were explored. The Ni/AC catalyst showed the best performance at gasification temperature of 800°C, S/B=4, Ni loading of 15wt.%. Texture and composition characterization of the catalysts suggested the interaction between volatiles and biochar promoted the reforming of pyrolysis volatiles. Cotton-char supported Ni exhibited the highest activity of H2 production (64.02vol.%, 92.08mgg(-1) biomass) from biomass gasification, while rice-char showed the lowest H2 production. PMID:27240230

  12. Gasification of peat and biomass in suspension flow 2; Turpeen ja biomassan suspensiokaasutus 2

    Energy Technology Data Exchange (ETDEWEB)

    Kurkela, E.; Hepola, J. [VTT Energy, Espoo (Finland); Haukka, P.; Vehmaan-Kreula, M.; Raiko, R. [Tampere Univ. of Technology (Finland)

    1996-12-01

    This project was an extension of the earlier Liekki-project 402 carried out in 1993-1994. The aims of the 1995 project were: (1) to study the formation of problematic tar/soot compounds and nitrogen pounds in the conditions of entrained flow gasification of biomass and peat, (2) study the product yields and kinetics of pyrolysis, and (3) to develop simulation methods for entrained flow pyrolysis and gasification. Pyrolysis and gasification tests were carried out at a new entrained flow reactor of the Gasification Research Group of VTT using mainly peat as the feedstock. The pyrolysis kinetics was studies using three particle size distributions of fuel peat (0.075-0.125 mm, 0.16-0.25 mm and 0.315-0.5 mm). The char yields were determined at two temperatures (900 and 1000 deg C) and the effects fuel to gas ratio (suspension density) as well as the effects of gas atmosphere were determined. Limited amount of tests were also carried out with pine wood and dried de-inking sludge. The formation of tars and nitrogen compounds was studied with peat as the feedstock. Based on the test results of this project and the on earlier fluidized-bed gasification data of VTT, the following conclusions can be made: (1) the char yields in rapid entrained flow pyrolysis of small particles of peat and biomass are considerably lower than derived in fluid-bed pyrolysis of more coarse feedstocks. Consequently, simple entrained flow reactors without any recycling of char could already give rather high carbon conversions. However, high carbon conversions can also be easily achieved in fluidized-bed gasifiers with biomass fuels due to the high gasification reactivity of the char, (2) more tars were formed in entrained flow pyrolysis of peat than in fluidized-bed experiments carried out at the same temperature, (3) the total conversion of peat nitrogen to NH{sub 3}+HCN was as high in the entrained flow pyrolysis as in the fluid-bed pyrolysis experiments. (Abstract Truncated)

  13. Comparison of mass and energy balances for air blown and thermally ballasted fluidized bed gasifiers

    International Nuclear Information System (INIS)

    The objective of this study was to compare the mass and energy balances for a conventional air blown fluidized bed gasifier and a ballasted fluidized bed gasifier developed at Iowa State University. The ballasted gasifier is an indirectly heated gasifier that uses a single reactor for both combustion and pyrolysis. Heat accumulated in high-temperature phase change material during the combustion phase is released during the pyrolysis phase to generate producer gas. Gas composition, tar and char contents, cold gas efficiency, carbon conversion, and hydrogen yield per unit biomass input were determined as part of these evaluation. During the pyrolysis phase of ballasted gasification, higher volumetric concentrations of hydrogen and methane were obtained than during air blown gasification. Hydrogen yield for ballasted gasification was 14 g kg−1 of biomass, which was about 20% higher than that obtained during air blown gasification. The higher heating value of the producer gas also reached higher levels during the ballasted pyrolysis phase than that of air blown gasification. Heating value for air blown gasification was 5.2 MJ m−3 whereas the heating value for the ballasted pyrolysis phase averaged 5.5 MJ m−3, reaching a maximum of 8.0 MJ m−3. The ballasted gasifier was expected to yield producer gas with average heating value as high as 15 MJ m−3 but excessive use of nitrogen to purge and cool the fuel feeder system greatly diluted the producer gas. Relatively simple redesign of the feeder system would greatly reduce the use of purge gas and may increase the heating values to about 17.5 MJ m−3. Higher char production per kilogram of biomass was associated with the ballasted system, producing 140 g kg−1 of biomass compared to only 53 g kg−1 of biomass during air blown gasification. On the other hand, tar concentrations in the producer gas were 6.0 g m−3 for ballasted gasification compared to 11.7 g m−3 for air blown gasification. On balance, carbon

  14. Experimental study on application of high temperature reactor excess heat in the process of coal and biomass co-gasification to hydrogen-rich gas

    International Nuclear Information System (INIS)

    The paper presents the results of the experimental study on the simulated application of HTR (High Temperature Reactor) excess heat in the process of allothermal co-gasification of coal and biomass. The laboratory scale installation with a fixed bed gasifier and auxiliary gasification agents pre-heating system, simulating the utilization of the HTR excess heat, were applied in the study. Steam and oxygen were the gasification media employed, and the process was focused on hydrogen-rich gas production. The results of the co-gasification of fuel blends of various biomass content at 800 °C and in various system configurations proved that the application of the simulated HTR excess heat in pre-heating of the gasification agents leads to the increase in the gaseous product yield. Furthermore, the HCA (Hierarchical Clustering Analysis) employed in the experimental data analysis revealed that the gasification of fuel blends of 20 and 40%w/w of biomass content results in higher volumes of the total gas, hydrogen, carbon monoxide and carbon dioxide than gasification of fuel blends of higher biomass content. - Highlights: • Simulated utilization of HTR excess heat in co-gasification of coal and biomass. • Assessment of three system configurations in terms of hydrogen production. • Application of the HCA in the experimental data set analysis. • Variation in gas components volume and content with fuel blend composition

  15. Benefits of Allothermal Biomass Gasification for Co-Firing

    Energy Technology Data Exchange (ETDEWEB)

    Van der Meijden, C.M.; Van der Drift, A.; Vreugdenhil, B.J. [ECN Biomass and Energy Efficiency, Petten (Netherlands)

    2012-04-15

    Many countries have set obligations to reduce the CO2 emissions from coal fired boilers. Co-firing of biomass in existing coal fired power plants is an attractive solution to reduce CO2 emissions. Co-firing can be done by direct mixing of biomass with coal (direct co-firing) or by converting the biomass into a gas or liquid which is fired in a separate burner (indirect co-firing). Direct co-firing is a rather simple solution, but requires a high quality and expensive biomass fuel (e.g. wood pellets). Indirect co-firing requires an additional installation that converts the solid biomass into a gas or liquid, but has the advantage that it can handle a wide range of cheap biomass fuels (e.g. demolition wood) and most of the biomass ash components are separated from the gas before it enters the boiler. Separation of biomass ash can prevent fouling issues in the boiler. Indirect co-firing, using biomass gasification technology, is already common practice. In Geertruidenberg (the Netherlands) a 80 MWth Lurgi CFB gasifier produces gas from demolition wood which is co-fired in the Amer PC boiler. In Ruien (Belgium) a 50 MWth Foster Wheeler fluidized bed gasifier is in operation. The Energy research Centre of the Netherlands (ECN) developed a 'second generation' allothermal gasifier called the MILENA gasifier. This gasifier has some major advantages over conventional fluidized bed gasifiers. The heating value of the produced gas is approximately 2.5 times higher than of gas produced by conventional bubbling / circulating fluidized bed gasifiers. This results in smaller adaptations to the membrane wall of the boiler for the gas injection, thus lower costs. A major disadvantage of most fluidized bed gasifiers is the incomplete conversion of the fuel. Typical fuel conversions vary between 90 and 95%. The remaining combustible material, also containing most of the biomass ash components, is blown out of the gasifier and removed from the gas stream by a cyclone to

  16. Investigating and analyzing parameters of coal gasification

    Energy Technology Data Exchange (ETDEWEB)

    Postrzednik, S.

    1983-07-01

    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.

  17. Gasification — the process and the technology

    OpenAIRE

    Swaaij, van, W.P.M.

    1981-01-01

    Thermochemical gasification of biomass can produce low, medium and high calorific value gases. The characteristics, applications and potential of the different processes and reactor types are discussed. The introduction of biomass gasification on a large or intermediate scale for the production of power, synthetic natural gas (SNG), methanol etc. will depend on developments in coal and (municipal) solid waste gasification and on the price of biomass. Biomass - and especially wood - is a clean...

  18. The characteristics of bed agglomeration during fluidized bed combustion of eucalyptus bark

    International Nuclear Information System (INIS)

    The bed agglomeration behaviors were investigated experimentally when eucalyptus bark was burning tested in a laboratory scale fluidized bed reactor. The focuses of this work were the influences of operating conditions and bed materials on the bed agglomeration tendency and the elucidation in the behaviors of fuel inorganic elements and the governing mode of the agglomeration. It was found that the defluidization caused by the bed agglomeration was clearly detectable from the decrease in measured bed pressure. The growth of bed particle and accumulation of agglomerates during combustion provided the partial to complete defluidization. The defluidization was promoted by the increase of bed temperature and bed particle size, and the decrease of fluidizing air velocity. The SEM-EDS analyses revealed that the bed agglomeration was mainly attributed to the formation of potassium silicate compounds as liquid phase during the combustion. This was initiated by the chemical reaction between the bed particle and the released ash constituents. In this study, the inorganic migration from fuel particle to bed particle was likely dominated by the condensation/reaction. The thermodynamic examination by ternary phase diagram analysis corroborated that the liquid phase formation of the ash derived materials controlled the agglomeration. The alumina sand prevented the bed agglomeration since it was inactive in the formation of viscous molten substances during combustion at the observed temperatures. - Highlights: • The behaviors of bed agglomeration were studied during the fluidized bed combustion of eucalyptus bark. • The increase in bed temperature and sand size, and the decrease of air velocity promoted bed defluidization. • The formation of molten potassium silicate compounds conduced to the bed agglomeration. • Condensation/reaction was the dominant inorganic migration mechanism from fuel particle to bed particle. • The alumina sand prevented effectively the bed

  19. Gasification - R and D opportunity

    International Nuclear Information System (INIS)

    This presentation is based on how gasification is viewed by industrial gas companies. It began with a assessment of the technology risk profile for gasification pointing out on the negative side: its high capital cost, low reliability, high start up costs are offset on the positive side by high flexibility in feed-stocks and relatively low CO2 capture costs. Comparing this with potential customer risk profiles the key development areas from an industrial gas perspective were identified as being process optimization around feedstocks and improving operability, and lowering costs in oxygen production, for which was described a potential Air Products breakthrough, the development of their ITM technology for oxygen production, which could reduce oxygen plant costs by more than 30%

  20. Changes in char reactivity due to char-oxygen and char-steam reactions using Victorian brown coal in a fixed-bed reactor

    Institute of Scientific and Technical Information of China (English)

    Shu Zhang; Yonggang Luo; Chunzhu Li; Yonggang Wang

    2015-01-01

    This study was to examine the influence of reactions of char–O2 and char–steam on the char reactivity evolution. A newly-designed fixed-bed reactor was used to conduct gasification experiments using Victorian brown coal at 800 °C. The chars prepared from the gasification experiments were then collected and subjected to reactivity characterisation (ex-situ reactivity) using TGA (thermogravimetric analyser) in air. The results indicate that the char reactivity from TGA was generally high when the char experienced intensive gasification reactions in 0.3%O2 in the fixed-bed reactor. The addition of steam into the gasification not only enhanced the char conversion sig-nificantly but also reduced the char reactivity dramatical y. The curve shapes of the char reactivity with involve-ment of steam were very different from that with O2 gasification, implying the importance of gasifying agents to char properties.

  1. Trace metal transformations in gasification

    Energy Technology Data Exchange (ETDEWEB)

    Erickson, T.A.; Zygarlicke, C.J.; O`Keefe, C.A. [and others

    1995-08-01

    The Energy & Environmental Research Center (EERC) is carrying out an investigation that will provide methods to predict the fate of selected trace elements in integrated gasification combined cycle (IGCC) and integrated gasification fuel cell (IGFC) systems to aid in the development of methods to control the emission of trace elements determined to be air toxics. The goal of this project is to identify the effects of critical chemical and physical transformations associated with trace element behavior in IGCC and IGFC systems. The trace elements included in this project are arsenic, chromium, cadmium, mercury, nickel, selenium, and lead. The research seeks to identify and fill, experimentally and/or theoretically, data gaps that currently exist on the fate and composition of trace elements. The specific objectives are to (1) review the existing literature to identify the type and quantity of trace elements from coal gasification systems, (2) perform laboratory-scale experimentation and computer modeling to enable prediction of trace element emissions, and (3) identify methods to control trace element emissions.

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

    Institute of Scientific and Technical Information of China (English)

    Yongzhuo Liu; Weihua Jia; Qingjie Guo; Hojung Ryu

    2014-01-01

    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.

  3. Pressurized Fluidized Bed Combustion Second-Generation System Research and Development

    Energy Technology Data Exchange (ETDEWEB)

    A. Robertson; D. Horazak; R. Newby; H. Goldstein

    2002-11-01

    Research is being conducted under United States Department of Energy (DOE) Contract DE-AC21-86MC21023 to develop a new type of coal-fired plant for electric power generation. This new type of plant--called a Second-Generation or Advanced Pressurized Circulating Fluidized Bed Combustion (APCFB) plant--offers the promise of efficiencies greater than 45% (HHV), with both emissions and a cost of electricity that are significantly lower than conventional pulverized-coal-fired plants with scrubbers. The APCFB plant incorporates the partial gasification of coal in a carbonizer, the combustion of carbonizer char in a pressurized circulating fluidized bed boiler (PCFB), and the combustion of carbonizer syngas in a topping combustor to achieve gas turbine inlet temperatures of 2300 F and higher. A conceptual design was previously prepared for this new type of plant and an economic analysis presented, all based on the use of a Siemens Westinghouse W501F gas turbine with projected carbonizer, PCFB, and topping combustor performance data. Having tested these components at the pilot plant stage, the referenced conceptual design is being updated to reflect more accurate performance predictions together with the use of the more advanced Siemens Westinghouse W501G gas turbine and a conventional 2400 psig/1050 F/1050 F/2-1/2 in. steam turbine. This report describes the updated plant which is projected to have an HHV efficiency of 48% and identifies work completed for the October 2001 through September 2002 time period.

  4. Mass and Energy Balances for Black Liquor Gasification with Borate Autocausticization

    Energy Technology Data Exchange (ETDEWEB)

    Arosenius, Anna-Karin

    2007-01-15

    Gasification of black liquor is considered to be a promising alternative technique for recovery of black liquor in kraft pulping. Compared to the conventional recovery process, i.e. combustion of black liquor in a recovery boiler, the primary advantage of gasification is the potential to produce biofuels and chemicals. The causticizing demand is though higher for the gasification technology. If the existing lime kiln can not handle the extra load, partial borate autocausticizing may be an alternative. In this work, the energy balance for a kraft pulp mill using black liquor gasification and partial borate autocausticization is compared with a mill using gasification and extended lime causticizing and also with a mill having a conventional recovery cycle. Additionally, the chemical costs for the partial borate autocausticizing is compared to the investment cost of the larger lime kiln. Mass and energy balances are based on the updated reference mill in the MISTRA Research Program, 'The Eco-Cyclic Pulp Mill', producing 2000 ADt of pulp per day. The results show that less energy is released to steam production in a gasifier than in a recovery boiler and instead energy is released in chemical form in the produced syn gas. Using partial borate autocausticizing, the demand of external energy is lowered in the lime kiln compared to extended lime causticization. The borate autocausticization, taking place in the gasifier with black liquor as energy source, only demands a third of the energy saved in the lime kiln. On the other hand the chemical costs for the borate autocausticization exceeds the investment cost for a larger lime kiln after five years.

  5. Equipment for gasification of pulverized fuel

    Energy Technology Data Exchange (ETDEWEB)

    Nosach, V.G.; Derevitskii, A.N.; Khopta, G.N.; Kocherezhko, A.N.; Vorob' ev, P.I.; Zholudov, Y.S.

    1981-02-25

    Equipment for gasification of pulverized fuel (PF) consisting of a vertical gasification chamber, a cinder removal chamber connected to the lower part of it, an injector for supplying the PF, a connecting pipe for supplying O/sub 2/-containing gas, a (steam) header for supplying steam located outside of the gasification chamber, and a pipe for drawing off the gasification products. The improvement, having the purpose of increasing the productive capacity, consists in this, that the gasification chamber has a burner located in the upper part of it with connecting pipes for supplying fuel and O/sub 2/ containing gas; the injectors for supplying PF are mounted in the walls of the gasification chamber at an angle to its vertical axis, are directed to the side of the burner, and are connected to the header for supplying steam. The pipe for drawing off the gasification products is located in the cinder removal chamber. In the case of coarser particles in the countercurrent inflow of combustion products and PF, finer ones are introduced into the stream of combustion products, which optimizes the reaction time of the different particles in accordance with their dispersity; 75% of the PF is gasified practically instantaneously because of the great difference in temperatures of the combustion products and PF (thermal shock), which makes it possible to accelerate the gasification process and increase the productive capacity of the equipment three-fold.

  6. Sewage sludge gasification characteristics and tar reduction using catalysts

    International Nuclear Information System (INIS)

    This study tested various types of catalysts such as dolomite steel slag and quicklime for tar reduction in the sewage sludge gasification process. For the experiments of sewage sludge gasification reaction characteristics and tar reduction using the catalysts a fixed bed of lab scale experimental apparatus was set up. The reactor was made of quartz glass using electric muffle furnaces. The sewage sludge samples were used with moisture content less than 6%. The catalysts were prepared using Dolomite (Seongshin Inc.) Steel slag (Hyundai Steel Co. Ltd.) Quicklime (Tae young EMC Co. LTD.). The experimental conditions were as follows sample weight was 20 g and reaction time was 10 minutes gasification reaction temperature was from 600 degree Celsius to 800 degree Celsius and the equivalence ratio was 0.2. Mass of catalysts were 2 g, 4 g, 6 g and temperatures of catalyst layer were 500 to 700 degree Celsius. The gas was analyzed for yield composition of product gas by GC/TCD(carbogen 1000 column) and tar composition of product gas by GC-mass(HP-Plan Al2O3/ KCl column). As reaction temperature increased up 800 degree Celsius yields of gaseous products and liquid products increased while char and tar products decreased which had effect on gas product compositions. These results were considered due to the increase of water gas reaction and Boudouard reaction. In the case of experiments with catalyst mass of catalysts were determined dolomite (4 g) steel slag (6 g) and quicklime (6 g) by previous experiments. When temperature of catalyst increased, weight of tar produced decreased with different cracking performance by catalysts. Reforming reaction on the surface of dolomite steel slag CaO of quicklime occurred caused by cracking of hydrocarbon structure. (author)

  7. Commercialisation BIVKIN-based gasification technology. Non-confidential version

    International Nuclear Information System (INIS)

    In 1996, the Netherlands Energy Research Foundation (ECN) in Petten, Netherlands, developed and built a circulating fluidized bed gasification process BIVKIN (Dutch abbreviation for biomass gasification installation) in co-operation with Novem, Afvalzorg and Stork. The plant was initially used at the ECN location in Petten for the characterisation of more than 15 different biomass species, including wood, sludge, grass and manure. During this test work, it was discovered that BIVKIN was an ideal tool for gasification of such diverse biomass at various thermal outputs. ECN has been conducting tests to improve the gas quality so that such fuel gas can be used for the generation of electricity by the use of a gas engine. In order to bring the BIVKIN technology to the commercial market, ECN, Shell and HoSt performed a study to evaluate the engineering concept and cost of such a design in detail. With this study, co-financed by Novem, the commercial viability of the BIVKIN technology in the electrical output range of 1 to 5 MW, is determined. For this relatively small scale, it is assumed that the extra positive cash flow due to selling the heat can compensate the higher investment per kW compared to large-scale systems where the produced heat generally cannot be used. This report is a reflection of the study to commercialise the BIVKIN technology. The BIVKIN-technology will be compared with alternative technologies commercially available for the power range under consideration. Both technical and economic evaluations will be presented. 12 refs

  8. Power Systems Development Facility Gasification Test Campaign TC25

    Energy Technology Data Exchange (ETDEWEB)

    Southern Company Services

    2008-12-01

    In support of technology development to utilize coal for efficient, affordable, and environmentally clean power generation, the Power Systems Development Facility (PSDF), located in Wilsonville, Alabama, routinely demonstrates gasification technologies using various types of coals. The PSDF is an engineering scale demonstration of key features of advanced coal-fired power systems, including a KBR Transport Gasifier, a hot gas particulate control device, advanced syngas cleanup systems, and high-pressure solids handling systems. This report summarizes the results of TC25, the second test campaign using a high moisture lignite coal from the Red Hills mine in Mississippi as the feedstock in the modified Transport Gasifier configuration. TC25 was conducted from July 4, 2008, through August 12, 2008. During TC25, the PSDF gasification process operated for 742 hours in air-blown gasification mode. Operation with the Mississippi lignite was significantly improved in TC25 compared to the previous test (TC22) with this fuel due to the addition of a fluid bed coal dryer. The new dryer was installed to dry coals with very high moisture contents for reliable coal feeding. The TC25 test campaign demonstrated steady operation with high carbon conversion and optimized performance of the coal handling and gasifier systems. Operation during TC25 provided the opportunity for further testing of instrumentation enhancements, hot gas filter materials, and advanced syngas cleanup technologies. The PSDF site was also made available for testing of the National Energy Technology Laboratory's fuel cell module and Media Process Technology's hydrogen selective membrane with syngas from the Transport Gasifier.

  9. Hazelnut shell to hydrogen-rich gaseous products via catalytic gasification process

    Energy Technology Data Exchange (ETDEWEB)

    Demirbas, A. [Selcuk Univ., Dept. of Chemical Engineering, Konya (Turkey)

    2004-01-15

    The gasification of biomass is a thermal treatment, which results in a high production of gaseous products and small quantities of char and ash. Steam reforming of hydrocarbons, partial oxidation of heavy oil residues, selected steam reforming of aromatic compounds, and gasification of coals and solid wastes to yield a mixture of H{sub 2} and CO (syngas), followed by a water-gas shift reaction to produce H{sub 2} and CO{sub 2}, are well-established processes. The samples, both untreated and impregnated with a catalyst, were pyrolyzed and gasified at 770, 925, 975, and 1025 K, and 975, 1075, 1175, and 1225 K temperatures, respectively. K{sub 2}CO{sub 3} was used as a catalyst, 10.0, 20.0, 30.0, and 50.0 wt% of the shell sample, in the catalytic-pyrolysis runs. The ratios of water-to-hazelnut shell were 0.7 and 1.9 in steam gasification runs. The total volume and the yield of gas from both pyrolysis and gasification increase with increasing temperature. The highest hydrogen-rich gas yield was obtained from the catalytic gasification run (water/hazelnut shell = 1.9) at 1225 K. (Author)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-07-01

    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.

  11. International Seminar on Gasification 2009 - Biomass Gasification, Gas Clean-up and Gas Treatment

    Energy Technology Data Exchange (ETDEWEB)

    2009-10-15

    During the seminar international and national experts gave presentations concerning Biomass gasification, Gas cleaning and gas treatment; and Strategy and policy issues. The presentations give an overview of the current status and what to be expected in terms of development, industrial interest and commercialization of different biomass gasification routes. The following PPT presentations are reproduced in the report: Black Liquor Gasification (Chemrec AB.); Gasification and Alternative Feedstocks for the Production of Synfuels and 2nd Generation Biofuels (Lurgi GmbH); Commercial Scale BtL Production on the Verge of Becoming Reality (Choren Industries GmbH.); Up-draft Biomass Gasification (Babcock and Wilcox Voelund A/S); Heterogeneous Biomass Residues and the Catalytic Synthesis of Alcohols (Enerkem); Status of the GoBiGas-project (Goeteborg Energi AB.); On-going Gasification Activities in Spain (University of Zaragoza,); Biomass Gasification Research in Italy (University of Perugia.); RDandD Needs and Recommendations for the Commercialization of High-efficient Bio-SNG (Energy Research Centre of the Netherlands.); Cleaning and Usage of Product Gas from Biomass Steam Gasification (Vienna University of Technology); Biomass Gasification and Catalytic Tar Cracking Process Development (Research Triangle Institute); Syngas Cleaning with Catalytic Tar Reforming (Franhofer UMSICHT); Biomass Gas Cleaning and Utilization - The Topsoee Perspective (Haldor Topsoee A/S); OLGA Tar Removal Technology (Dahlman); Bio-SNG - Strategy and Activities within E.ON (E.ON Ruhrgas AG); Strategy and Gasification Activities within Sweden (Swedish Energy Agency); 20 TWh/year Biomethane (Swedish Gas Association)

  12. PLASMA GASIFICATION OF WASTE PLASTICS

    Directory of Open Access Journals (Sweden)

    Tadeusz Mączka

    2013-01-01

    Full Text Available The article presents the process of obtaining liquid fuels and fuel gas in the process of plasma processing of organic materials, including waste plastics. The concept of plasma pyrolysis of plastics was presented and on its basis a prototype installation was developed. The article describes a general rule of operating the installation and its elements in the process and basic operation parameters determined during its start-up. Initial results of processing plastics and the directions further investigations are also discussed. The effect of the research is to be the design of effective technology of obtaining fuels from gasification/pyrolysis of organic waste and biomass.

  13. Calcium addition in straw gasification

    DEFF Research Database (Denmark)

    Risnes, H.; Fjellerup, Jan Søren; Henriksen, Ulrik Birk; Moilanen, A.; Norby, P.; Papadakis, K.; Posselt, D.; Sørensen, L. H.

    2003-01-01

    The present work focuses on the influence of calcium addition in gasification. The inorganic¿organic element interaction as well as the detailed inorganic¿inorganic elements interaction has been studied. The effect of calcium addition as calcium sugar/molasses solutions to straw significantly...... affected the ash chemistry and the ash sintering tendency but much less the char reactivity. Thermo balance test are made and high-temperature X-ray diffraction measurements are performed, the experimental results indicate that with calcium addition major inorganic¿inorganic reactions take place very late...

  14. Calcium addition in straw gasification

    DEFF Research Database (Denmark)

    Risnes, H.; Fjellerup, Jan Søren; Henriksen, Ulrik Birk;

    2003-01-01

    The present work focuses on the influence of calcium addition in gasification. The inorganic¿organic element interaction as well as the detailed inorganic¿inorganic elements interaction has been studied. The effect of calcium addition as calcium sugar/molasses solutions to straw significantly...... affected the ash chemistry and the ash sintering tendency but much less the char reactivity. Thermo balance test are made and high-temperature X-ray diffraction measurements are performed, the experimental results indicate that with calcium addition major inorganic¿inorganic reactions take place very late...... calcium binds silicon primarily as calcium silicates and less as potassium calcium silicates....

  15. Process characteristics and products of olive kernel high temperature steam gasification (HTSG).

    Science.gov (United States)

    Skoulou, V; Swiderski, A; Yang, W; Zabaniotou, A

    2009-04-01

    Exploitation of olive kernel for bioenergy production, with respect to the green house gases (GHGs) mitigation, is the main aim of this work. In this study, olive kernels were used as a solid biofuel, and high temperature steam gasification (HTSG) was investigated, in the fixed bed unit at KTH Sweden, with regard to hydrogen maximization in the produced gasification gas. Experiments were carried out in a temperature range of 750-1050 degrees C, with steam as the gasifying agent. The behaviour of olive kernels, under residence times from 120 up to 960 s, has been studied. At 1050 degrees C, a medium to high calorific value gas was obtained (LHVgas=13.62 MJ/Nm3), while an acquired H2/CO molar ratio equal to four proved that olive kernel HTSG gasification could be an effective technology for a hydrogen-rich gas production (approximately 40%vv H2 in the produced gasification gas at 1050 degrees C). The produced char contained 79%ww of fixed carbon, low chlorine and sulphur content, which enables it for further re-use for energetic purposes. Tar content in the produced gas at 750 degrees C was 124.07 g/Nm3, while a 1050 degrees C at 79.64% reduction was observed and reached the value of 25.26 g/Nm3. PMID:19117753

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

    International Nuclear Information System (INIS)

    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

  17. Process simulation of biomass gasification integrated with a solid oxide fuel cell stack

    Science.gov (United States)

    Doherty, Wayne; Reynolds, Anthony; Kennedy, David

    2015-03-01

    Biomass gasification-solid oxide fuel cell (BG-SOFC) combined heat and power (CHP) systems are of major interest in the context of climate change mitigation, energy security and increasing energy efficiency. Aspen Plus is employed to simulate various BG-SOFC CHP systems. The aim of the research work is to investigate the technical feasibility of these systems and to study the influence of important operating parameters and examine integration options. Systems based on dual fluidised bed steam gasification and tubular SOFC technologies are modelled. The cathode recycle and electric heater integration options are not attractive in comparison to the base case anode recycle system. Thermal integration, i.e. using SOFC flue gas as gasifier oxidant, is desirable. Lowering the syngas preheat temperature (prior to SOFC anodes) is highly recommended and is more practical than lowering the cathode air preheat temperature. Results of the parametric study indicate that: steam to carbon ratio and biomass moisture content should be as low as possible; fuel utilisation factor can change the mode of operation of the plant (focus on electricity or heat); high temperature syngas cleaning is very attractive; gasification air preheating is more attractive than gasification steam superheating. High efficiencies are predicted, proving the technical feasibility of BG-SOFC CHP systems.

  18. Syngas production by gasification of aquatic biomass with CO2/O2 and simultaneous removal of H2S and COS using char obtained in the gasification

    International Nuclear Information System (INIS)

    Applicability of gulfweed as feedstock for a biomass-to-liquid (BTL) process was studied for both production of gas with high syngas (CO + H2) content via gasification of gulfweed and removal of gaseous impurities using char obtained in the gasification. Gulfweed as aqueous biomass was gasified with He/CO2/O2 using a downdraft fixed-bed gasifier at ambient pressure and 900 °C at equivalence ratios (ER) of 0.1–0.3. The syngas content increased while the conversion to gas on a carbon basis decreased with decreasing ER. At an ER of 0.1 and He/CO2/O2 = 0/85/15%, the syngas content was maximized at 67.6% and conversion to gas on a carbon basis was 94.2%. The behavior of the desulfurization using char obtained during the gasification process at ER = 0.1 and He/CO2/O2 = 0/85/15% was investigated using a downdraft fixed-bed reactor at 250–550 °C under 3 atmospheres (H2S/N2, COS/N2, and a mixture of gases composed of CO, CO2, H2, N2, CH4, H2S, COS, and steam). The char had a higher COS removal capacity at 350 °C than commercial activated carbon because (Ca,Mg)S crystals were formed during desulfurization. The char simultaneously removed H2S and COS from the mixture of gases at 450 °C more efficiently than did activated carbon. These results support this novel BTL process consisting of gasification of gulfweed with CO2/O2 and dry gas cleaning using self-supplied bed material. -- Highlights: • A product gas with high syngas content was produced from the gasification of gulfweed with CO2/O2. • The syngas content increased with decreasing the equivalence ratio. • The syngas content was maximized at 67.6% at an ER of 0.1 and He/CO2/O2 = 0/85/15%. • The char simultaneously removed H2S and COS from a mixture of gases at 450 °C efficiently

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

    International Nuclear Information System (INIS)

    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)

  20. Gasification from waste organic materials

    OpenAIRE

    Santiago Ramírez Rubio; Fabio Emiro Sierra; Carlos Alberto Guerrero

    2011-01-01

    This article describes the fixed bed biomass gasifier operation designed and built by the Clean Development Mechanisms and Energy Management research group, the gasifier equipment and the measurement system. The experiment involved agro-industrial residues (biomass such wood chips, coconut shell, cocoa and coffee husk); some temperatures along the bed, its pressure, inlet air flow and the percentage of carbon monoxide and carbon dioxide in the syngas composition were measured. The test result...

  1. Macauba gasification; Gaseificacao da macauba

    Energy Technology Data Exchange (ETDEWEB)

    Santos Filho, Jaime dos; Oliveira, Eron Sardinha de [Instituto Federal de Educacao, Ciencia e Tecnologia da Bahia (IFBA), Vitoria da Conquista, BA (Brazil)], E-mail: jaime@ifba.edu.br; Silva, Jadir Nogueira da; Galvarro, Svetlana Fialho Soria [Universidade Federal de Vicosa (UFV), MG (Brazil); Chaves, Modesto Antonio [Universidade Estadual do Sudoeste da Bahia (UESB), Itapetinga, BA (Brazil). Dept. de Engenharia de Alimentos

    2009-07-01

    For development of a productive activity, with reduced environmental degradation, the use of renewable energy sources as an important option. The gasification has been increasing among the ways of obtaining energy from biomass, and consists of a process where the necessary oxygen to the complete combustion of a fuel it is restricts and, in high temperatures it generates fuel gas of high-quality. In this direction, this work is justified and has its importance as the study of a renewable energy source, macauba coconut (Acrocomia aculeata [Jacq] Lodd), with the gasification process. The objective of this study is to build a biomass concurrent gasifier and evaluate the viability to provide heating for dehydration of fruits, using the macauba coconut as fuel. It was measured the temperature in five points distributed in both gasifier and combustor chamber, being the input area of primary combustor air and also the speed of rotation of the electric motor, using a factorial 3X3 experimental design with three repetitions and interval of measurements of five minutes. The analytical results take to infer that the macauba coconut have potential to be gasified and used for the dehydration of fruits. (author)

  2. Groundwater Pollution from Underground Coal Gasification

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    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.

  3. Chaotic Study in a Large Jetting Fluidized Bed with a Vertical Nozzle

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@1 INTRODUCTION Jetting fluidized beds have been widely applied in such processes as catalytic and flame reactions, combustion and gasification of coal, treatment of waste, cleaning of dusty gases, coating and granulation[1-3]. The flow characteristics of jetting fiuidized beds are relevant to the stable gas jet and the high rates of heat transfer and mass transfer, and the fast chemical reaction pro cess near the gas distributor.

  4. Integrated gasification combined cycle (IGCC): an environmentally benign and efficient energy option for India

    International Nuclear Information System (INIS)

    As compared to coal fired thermal power plant, integrated gasification combined cycle (IGCC) based power plant have advantages of lower emissions, less water consumption, higher efficiency, and flexibilities of small module construction and phased construction. IGCC technology, therefore, is an attractive alternative for future power generation in India, provided out of the gasification processes, one suitable for high ash coals available in India is chosen for IGCC plants in India. Four gasification processes, namely, dry entrained (DE), slurry entrained (SE), fluidized bed (FB), and moving bed (MB) are outlined and compared. The data for the MB process were obtained from the tests conducted on 1 t/hr pilot plant at Indian Institute of Chemical Technology, Hyderabad and 150 t/day combined cycle demonstration plant at Bharat Heavy Electricals Ltd., Trichy. Both plants used high ash Indian coal. Conclusions arrived at on the basis of the above experimental data and published data for other processes show that SE processes is not suitable for high ash coals of India, and FB process has a superior heat rate. Capital cost and power generation cost of FB based plant compares well with those of coal-fired plant. However, it is noted that in the absence of any experience with the use of high ash coals in FB process, a demonstration plant using high ash coals is required to be constructed to establish the techno-commercial viability of FB based IGCC technology in India. (M.G.B.). 10 refs., 11 tabs., 3 figs

  5. Review and analysis of biomass gasification models

    DEFF Research Database (Denmark)

    Puig Arnavat, Maria; Bruno, Joan Carles; Coronas, Alberto

    2010-01-01

    The use of biomass as a source of energy has been further enhanced in recent years and special attention has been paid to biomass gasification. Due to the increasing interest in biomass gasification, several models have been proposed in order to explain and understand this complex process, and the...... design, simulation, optimisation and process analysis of gasifiers have been carried out. This paper presents and analyses several gasification models based on thermodynamic equilibrium, kinetics and artificial neural networks. The thermodynamic models are found to be a useful tool for preliminary...

  6. BIOMASS GASIFICATION AND POWER GENERATION USING ADVANCED GAS TURBINE SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    David Liscinsky

    2002-10-20

    A multidisciplined team led by the United Technologies Research Center (UTRC) and consisting of Pratt & Whitney Power Systems (PWPS), the University of North Dakota Energy & Environmental Research Center (EERC), KraftWork Systems, Inc. (kWS), and the Connecticut Resource Recovery Authority (CRRA) has evaluated a variety of gasified biomass fuels, integrated into advanced gas turbine-based power systems. The team has concluded that a biomass integrated gasification combined-cycle (BIGCC) plant with an overall integrated system efficiency of 45% (HHV) at emission levels of less than half of New Source Performance Standards (NSPS) is technically and economically feasible. The higher process efficiency in itself reduces consumption of premium fuels currently used for power generation including those from foreign sources. In addition, the advanced gasification process can be used to generate fuels and chemicals, such as low-cost hydrogen and syngas for chemical synthesis, as well as baseload power. The conceptual design of the plant consists of an air-blown circulating fluidized-bed Advanced Transport Gasifier and a PWPS FT8 TwinPac{trademark} aeroderivative gas turbine operated in combined cycle to produce {approx}80 MWe. This system uses advanced technology commercial products in combination with components in advanced development or demonstration stages, thereby maximizing the opportunity for early implementation. The biofueled power system was found to have a levelized cost of electricity competitive with other new power system alternatives including larger scale natural gas combined cycles. The key elements are: (1) An Advanced Transport Gasifier (ATG) circulating fluid-bed gasifier having wide fuel flexibility and high gasification efficiency; (2) An FT8 TwinPac{trademark}-based combined cycle of approximately 80 MWe; (3) Sustainable biomass primary fuel source at low cost and potentially widespread availability-refuse-derived fuel (RDF); (4) An overall integrated

  7. Advancement of High Temperature Black Liquor Gasification Technology

    Energy Technology Data Exchange (ETDEWEB)

    Craig Brown; Ingvar Landalv; Ragnar Stare; Jerry Yuan; Nikolai DeMartini; Nasser Ashgriz

    2008-03-31

    Weyerhaeuser operates the world's only commercial high-temperature black liquor gasifier at its pulp mill in New Bern, NC. The unit was started-up in December 1996 and currently processes about 15% of the mill's black liquor. Weyerhaeuser, Chemrec AB (the gasifier technology developer), and the U.S. Department of Energy recognized that the long-term, continuous operation of the New Bern gasifier offered a unique opportunity to advance the state of high temperature black liquor gasification toward the commercial-scale pressurized O2-blown gasification technology needed as a foundation for the Forest Products Bio-Refinery of the future. Weyerhaeuser along with its subcontracting partners submitted a proposal in response to the 2004 joint USDOE and USDA solicitation - 'Biomass Research and Development Initiative'. The Weyerhaeuser project 'Advancement of High Temperature Black Liquor Gasification' was awarded USDOE Cooperative Agreement DE-FC26-04NT42259 in November 2004. The overall goal of the DOE sponsored project was to utilize the Chemrec{trademark} black liquor gasification facility at New Bern as a test bed for advancing the development status of molten phase black liquor gasification. In particular, project tasks were directed at improvements to process performance and reliability. The effort featured the development and validation of advanced CFD modeling tools and the application of these tools to direct burner technology modifications. The project also focused on gaining a fundamental understanding and developing practical solutions to address condensate and green liquor scaling issues, and process integration issues related to gasifier dregs and product gas scrubbing. The Project was conducted in two phases with a review point between the phases. Weyerhaeuser pulled together a team of collaborators to undertake these tasks. Chemrec AB, the technology supplier, was intimately involved in most tasks, and focused primarily on the

  8. Na/Ca catalyzation of Illinois coals for gasification. Final technical report, September 1, 1992--August 31, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Jha, M.C.; McCormick, R.L. [AMAX Research and Development Center, Golden, CO (United States)

    1993-12-31

    Gasification for power generation via IGCC processes is expected to become an important market for high sulfur Illinois Basin coals. Fluid-bed gasifiers have significant advantages over entrained flow processes. These advantages include ease of control, large turndown capacity, high thermal efficiency, and moderate oxygen and steam requirements. Three of the most pressing technical problems in fluid-bed gasification of Illinois coals are the caking tendency, high sulfur content, and low carbon conversion and consequent large char recycle required in most systems. This program explores the use of gasification catalysts to attack these three problems. The catalysts are sodium/calcium mixtures. Another advantage of using catalysts is that gasification temperature might be lowered, leading to less expensive materials of construction and a reduction in alkali vaporization. The results of this study indicate that these catalysts can reduce or eliminate the caking of Illinois coals. Loadings below 1 weight % were effective if the catalyst was added by impregnation at low pH (below about 5). An Na/Ca molar ratio of greater than 1 also leads to lower catalyst requirement.

  9. A comparative study of gasification of food waste (FW), poultry waste (pw), municipal solid waste (MSW) and used tires (UT)

    International Nuclear Information System (INIS)

    The rate and volume of generation of waste material in the developing societies has increased significantly. Correspondingly the demand of energy has increased many folds. One of the options in this situation is to recover the energy value of the waste material for production of power and heat through gasification. Gasification of materials is a proven concept and its environmental benefits are known. The characteristic behavior and scope of gasification of four waste materials namely steam treated Food Waste (FW), Poultry Waste (PW), steam treated Municipal Solid Waste (MSW) and Used Tyres (UT) have been studied in a 10 kg/hr hybrid gasification plant. This pilot plant consists of a fixed bed gasifier followed by a two in one cyclone scrubber for gas cleaning and a flare system. Various laboratory tests of these materials through proximate, ultimate analysis and stove test were conducted to establish their fuel characteristics. These materials were gasified to generate synthesis gas. It was observed that FW and UT offer sustainable potential for energy recovery. MSW on the other hand had considerable ash and had difficulties during gasification. PW could only be gasified when mixed with charcoal or high CV UT in order to balance against its high moisture. The gas analysis of the waste indicated significant quantities of hydrogen and carbon monoxide. (author)

  10. Analysis of Organic and Inorganic Contaminants in Dried Sewage Sludge and By-Products of Dried Sewage Sludge Gasification

    Directory of Open Access Journals (Sweden)

    Sebastian Werle

    2014-01-01

    Full Text Available Organic and inorganic contaminants in sewage sludge may cause their presence also in the by-products formed during gasification processes. Thus, this paper presents multidirectional chemical instrumental activation analyses of dried sewage sludge as well as both solid (ash, char coal and liquid (tar by-products formed during sewage gasification in a fixed bed reactor which was carried out to assess the extent of that phenomenon. Significant differences were observed in the type of contaminants present in the solid and liquid by-products from the dried sewage sludge gasification. Except for heavy metals, the characteristics of the contaminants in the by-products, irrespective of their form (solid and liquid, were different from those initially determined in the sewage sludge. It has been found that gasification promotes the migration of certain valuable inorganic compounds from sewage sludge into solid by-products which might be recovered. On the other hand, the liquid by-products resulting from sewage sludge gasification require a separate process for their treatment or disposal due to their considerable loading with toxic and hazardous organic compounds (phenols and their derivatives.

  11. Steam gasification of carbon: Catalyst properties

    Energy Technology Data Exchange (ETDEWEB)

    Falconer, J.L.

    1991-09-16

    This research uses several techniques to measure the concentration of catalyst sites and determine their stoichiometry for the catalyzed gasification of carbon. Both alkali and alkaline earth oxides are effective catalysts for accelerating the gasification rate of coal chars, but only a fraction of the catalyst appears to be in a form that is effective for gasification, and the composition of that catalyst is not established. Transient techniques, with {sup 13}C labeling, are being used to study the surface processes, to measure the concentration of active sites, and to determine the specific reaction rates. We have used secondary ion mass spectroscopy (SIMS) for both high surface area samples of carbon/alkali carbonate mixtures and for model carbon surfaces with deposited alkali atoms. SIMS provides a direct measure of surface combination of these results can provide knowledge of catalyst dispersion and composition, and thus indicate the way to optimally utilize carbon gasification catalysts.

  12. Experimental and modeling analysis of a batch gasification/pyrolysis reactor

    International Nuclear Information System (INIS)

    This paper presents some experimental results about biomass gasification obtained with a bench-scale gasifier consisting of an indirectly heated batch reactor, inserted in a high temperature furnace. Spruce wood has been used as feedstock in different forms and sizes (as pellets and sawdust). The experimental activity includes the analysis of the thermal response of the system (using an inert bed material) and the characterization of the gasification products. The yield of the gaseous compounds found in the syngas has been measured using an on-line gas-chromatography technique. The experimental results have been compared against calculations obtained by applying a thermochemical equilibrium model, improved to predict both the gas and the solid phase product yields. The experimental (average) yield of reaction products has been found to be in a satisfying agreement with the thermodynamic model.

  13. CFB gasification of biomass. An analysis of available and necessary research facilities

    International Nuclear Information System (INIS)

    The aim of the title analysis is to inventorize the required and available Dutch laboratory facilities for research on Circulating Fluidized Beds (CFB) gasification of biomass. A literature study has been carried to assess the international state-of-the-art of the technology and research. Based on the results the required research facilities could be determined. Next, interviews were held with researchers at relevant Dutch research institutes and information was collected to compile an overview of available Dutch facilities. It appears that the introduction of CFB gasification technologies can take place under good conditions, although coordination of future research activities is desired, while knowledge and facilities are spread over several research institutes. 16 figs., 43 refs., 1 appendix

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

    Science.gov (United States)

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

    2013-08-01

    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

  15. Thermodynamic approach to biomass gasification

    International Nuclear Information System (INIS)

    The document presents an approach of biomass transformation in presence of steam, hydrogen or oxygen. Calculation results based on thermodynamic equilibrium are discussed. The objective of gasification techniques is to increase the gas content in CO and H2. The maximum content in these gases is obtained when thermodynamic equilibrium is approached. Any optimisation action of a process. will, thus, tend to approach thermodynamic equilibrium conditions. On the other hand, such calculations can be used to determine the conditions which lead to an increase in the production of CO and H2. An objective is also to determine transformation enthalpies that are an important input for process calculations. Various existing processes are assessed, and associated thermodynamic limitations are evidenced. (author)

  16. Robustness studies on coal gasification process variables

    OpenAIRE

    RLJ Coetzer; MJ Keyser

    2004-01-01

    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-...

  17. Corrosion during gasification of biomass and waste

    OpenAIRE

    Källström, Rikard

    1993-01-01

    The gasification of biomass and waste results in severe atmospheric corrosion conditions. The problems arise because of the low oxygen content which prevents the metal forming stable and protective oxide surface layer. Consequently it is possible for the aggressive sulphur and chlorine present in the gas to attack the metal. In the Studsvik CFB gasification pilot plant, which uses RDF (Refuse Derived Fuel), the performance of 20 metallic and ceramic materials has been studied. Materials teste...

  18. Coal gasification for electric power generation.

    Science.gov (United States)

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

    1982-03-26

    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

  19. High Temperature Air/Steam Gasification of Biomass Wastes - Stage 1. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Blasiak, Wlodzimierz; Szewczyk, Dariusz; Lucas, Carlos; Rafidi, Nabil; Abeyweera Ruchira; Jansson, Anna; Bjoerkman, Eva [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Materials Science and Engineering

    2003-05-01

    In Jan 2002 the Division of Energy and Furnace Technology started the project High Temperature Air an Steam Gasification (HTAG) of biomass wastes, following the approval made by Swedish Energy Agency. The research proved successful; with the fixed bed updraft gasifier coupled to the highly regenerative preheater equipment able to produce a fuel gas not only from wood pellets but also from wood chips, bark and charcoal with considerably reduced amount of tar. This report provides information on solid biomass conversion into fuel gas as a result of air and steam gasification process performed in a fixed bed updraft gasifier. The first chapter of the report presents the overall objectives and the specific objectives of the work. Chapter 2 summarizes state-of-the-art on the gasification field stating some technical differences between low and high temperature gasification processes. Description and schemes of the experimental test rig are provided in Chapter 3. The equipment used to perform measurements of different sort and that installed in the course of the work is described in Chapter 4. Chapter 5 describes the methodology of experiments conducted whose results were processed and evaluated with help of the scheme of equations presented in Chapter 6, called raw data evaluation. Results of relevant experiments are presented and discussed in Chapter 7. A summary discussion of the tar analysis is presented in Chapter 8. Chapter 9 summarizes the findings of the research work conducted and identifies future efforts to ensure the development of next stage. Final chapter provides a summary of conclusions and recommendations of the work. References are provided at the end of the report. Aimed to assist the understanding of the work done, tables and graphs of experiments conducted, irrespective to their quality, are presented in appendices.

  20. Detailed process modeling of a wood gasification combined heat and power plant

    International Nuclear Information System (INIS)

    We provide the first process simulation able to depict a complete life cycle inventory of a biomass gasification combined heat and power (CHP) plant. The model predicts the detailed mass and energy balances, minor compounds emissions (such as NOx, SOx, aromatics, etc.). It is based on a phenomenological approach for dryer, reactors (gasification and combustion) and scrubber modeling. Process units are modeled with Aspen Plus® models completed with dedicated Fortran sub-models when more details are required. The gasifier is a Dual Fluidized Bed (DFB). It is decomposed in three sections, describing the three main mechanisms occurring in the reactor: wood pyrolysis, secondary reactions and char combustion. At the outlet of the gasifier, the complete composition of the syngas is predicted, which includes water, permanent gases, inorganics, particles and tars (phenol, benzene, toluene, styrene, indene, naphthalene, acenaphthylene, anthracene, phenanthrene, pyrene). Simulation results were validated against measurements from a pilot plant and other literature data. A wet conventional syngas cleaning system for gasification plant, including cyclone, catalytic tar cracker, syngas cooler, bag filters, water scrubber and wastewater treatment was considered and modeled. The complexity of tar composition allows a reliable determination of tar dew point. At the outlet of the cleaning system, syngas is burned in gas engines. Gaseous emissions (NOx, SOx, etc.) of the gas engines and the DFB combustor are also handled by the model as well as ashes and liquid waste. The predicted electrical and thermal efficiencies are 27 and 39% respectively. Highlights: ► A new model of a biomass gasification combined heat and power plant is presented. ► The whole gasification process is modelled under Aspen Plus from dryer to gas engine. ► Heat streams are integrated for internal needs and district heating. ► Tar and inorganic compounds are predicted. ► A detailed life cycle inventory

  1. Comparative study on the combustion and gasification of solid recovered fuels. Emphasis on residues characterisation and chlorine partitioning

    OpenAIRE

    Balampanis, Dimitris E.

    2009-01-01

    Thermal treatment is recognised as a valid option within the waste management hierarchy for the recovery of the energy content of waste. Recent developments in the field are signposted from emergent technologies and the standardisation of solid recovered fuels. This work comparatively examines the fluidized bed combustion and gasification of a novel material; East London’s solid recovered fuel. Emphasis is given on the characterisation of the solid residues produced from the two thermal ...

  2. The formation of nitrogen compounds at gasification/pyrolysis condition

    Energy Technology Data Exchange (ETDEWEB)

    Bjoerkman, E.; Nilsson, Torbjoern; Stroemberg, B. [TPS Termiska Processer AB, Nykoeping (Sweden)

    1998-08-01

    A kinetic model by which it is possible to determine reactions constants for the formation/destruction of hydrogen cyanide and ammonia from fuel-N during pyrolysis/gasification conditions in presence of an internal catalyst is here presented, together with the possibilities to experimentally support the model with data. The experiments were performed in a small fixed bed quarts reactor, the bed materials were CaO and iron doped CaO. The fuel used was a liquid mixture of pyridine, ethylene glycol and formic acid (25 mole-% C, 49 mole-% H, 24 mole-% 0 and 1.8 mole-% of N). The product gas was analysed for NH{sub 3}, HCN, NO, CO, CO{sub 2}, CH{sub 4} and C{sub 2}H{sub 4} with an FTIR. For some of the experiments a gas chromatograph with double thermal conductivity detectors (TCD) was used to measure the nitrogen gas formation. Changing the contact time with the iron doped CaO gave significant changes in mainly ammonia and nitrogen monoxide concentrations. The decomposition of hydrogen cyanide has also been studied, showing that no ammonia was formed from HCN during the experimental conditions used 26 refs, 8 figs, 1 appendix

  3. Japan`s Sunshine Project. 1991 annual summary of coal liquefaction and gasification; 1991 nendo sunshine keikaku seika hokokusho gaiyoshu. Sekitan no ekika gas ka

    Energy Technology Data Exchange (ETDEWEB)

    1992-07-01

    Out of the research and development on the 1991 Sunshine Project, the results of coal liquefaction/gasification are reported. The basic research of coal liquefaction/gasification is conducted. The research plan for a 150 ton/day scale pilot plant (PP) is worked out for the development of bituminous coal liquefaction technology by NEDOL process. Data of PSU (Process Support Units) operation, especially, are studied. Concerning the data obtained through dismantling of the 50 ton/day PP in Australia which uses Australian Victoria coal due to completion of its operation and also obtained from its support research, they are reflected in the design of a demonstration plant, and the results are arranged for study. Research and development on refining technology of coal-derived liquid such as Illinois coal liquid and on application technology of its products are made. For the development of coal-use hydrogen production technology, conducted is the research of a high temperature gasification PP by entrained flow bed process which is the core of the coal gasification technology. Elementary study with a 2 ton/day furnace is made for the development of the entrained flow bed coal gasification combined cycle power generation system. Also conducted are PP construction, adjusting operation and the overall research operation.

  4. Experimental investigations on a 20 kWe, solid biomass gasification system

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Avdhesh Kr. [Mechanical Engg. Department, D.C.R. University of Science and Technology, Murthal (Sonepat)-131039 (India)

    2011-01-15

    When the objective is to generate motive or electric power via I.C. engine, the overall pressure drop through the suction gasification system in addition to gas quality has become a sensitive issue. This work, therefore, presents an experimental study on a suction gasifier (downdraft) arrangement operating on kiker wood or Acacia nilotica (L). Studies were conducted to investigate the influence of fluid flow rate on pressure drop through the gasifier system for ambient isothermal airflow and ignited mode, pumping power, and air-fuel ratio, gas composition and gasification efficiency. Results of pressure drop, temperature profile, gas composition or calorific value are found to be sensitive with fluid flow rate. Ignited gasifier gives much higher pressure drop when compared against newly charged gasifier bed with isothermal ambient airflow. Higher reaction temperatures in gasifier tends to enhance gasifier performance, while, overall pressure drop and thus pumping power through the system increases. Both ash accumulated gasifier bed and sand bed filters with tar laden quartz particles also show much higher pressure drops. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2005-06-01

    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.

  6. Large scale experiments and modeling of black liquor gasification

    Energy Technology Data Exchange (ETDEWEB)

    Carlsson, Per

    2011-07-01

    Biomass gasification could provide a basis for increased electricity and engine fuel production from a renewable source in the pulp and paper industry. This work focuses on the largest byproduct available at the pulp mills, black liquor. Black liquor is a mixture of spent cooking chemicals, dissolved lignin, dissolved carbohydrates and a small portion of inorganic compounds found in the wood. The conventional technology to recover the cooking chemicals and the chemical energy as heat is combustion in large boilers. Here, gasification could be an alternative, replacing or complementing the boilers. The gasification technology produces a combustible gas that can be cleaned to produce electricity in a gas turbine/engine or, be synthesized into valuable chemicals or liquid engine fuels. The technology has been demonstrated in development scale since 2005 and appears to be promising. Still, commercial plants have not yet been built. This thesis focuses on the understanding of the oxygen blown, pressurized, entrained flow, black liquor gasification technology. The main goals have been to increase the understanding about the dominating mechanisms in black liquor gasification and to develop an engineering tool that can be used to design and optimize, pressurized, entrained flow, black liquor gasifiers. To accomplish these goals gas samples were extracted from the gasification reactor using a gas sampling probe that was developed within this work. Gas samples were also collected downstream the quench located underneath the reactor and the results were compared. Finally, an existing numerical model was developed so it can predict the behavior of the black liquor gasifier within reasonable accuracy. Even though the actual mechanisms in the reactor and quench are very complex it appears that they can be described with relatively simple global mechanisms. The main gas components are dictated by the water gas shift reaction. At the outlet of the reactor the gas composition is

  7. WABASH RIVER COAL GASIFICATION REPOWERING PROJECT; FINAL

    International Nuclear Information System (INIS)

    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

  8. WABASH RIVER COAL GASIFICATION REPOWERING PROJECT

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2000-09-01

    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.

  9. Optimisation of Experimental Conditions for Ex-Bed Desulfurization

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, J. M.; Ruiz, E.; Otero, J.

    2010-12-22

    This report compiles the results of the work conducted by CIEMAT for Task 6.3 Sulfur and Nitrogen Compounds Abatement of the FLEXGAS project Near Zero Emission Advanced Fluidized Bed Gasification, which has been carried out with financial support from the Research Fund for Coal and Steel, RFCR-CT-2007-00005. The assignment of CIEMAT in Task 6.3 has dealt with the experimental study of ex-bed desulfurization at high temperature and high pressure. Based on a review of the state of the art, a zinc oxide sorbent was chosen as a promising candidate for bulk sulfur removal in highly reducing gases such as those from coal and waste oxygen gasification or for a polishing stage in low sulfur content gases, which is typically the case in biomass gasification gases. The work accomplished has included the study of the sulfidation and regeneration stages in order to determine successful operating conditions and the assessment of the long term performance of the sorbent over subsequent sulfidation and regeneration cycles. (Author) 36 refs.

  10. Partial priapism

    DEFF Research Database (Denmark)

    Høyerup, Peter; Dahl, Claus; Azawi, Nessn Htum

    2014-01-01

    Partial priapism, also called partial segmental thrombosis of the corpus cavernosum, is a rare urological condition. Factors such as bicycle riding, drug usage, penile trauma and haematological diseases have been associated with the condition. Medical treatment with low molecular weight heparin (...... (LMWH) or acetylsalicylic acid is first choice treatment, and surgery is preserved for patients unresponsive to analgesics. In this report we describe the case of a 70-year-old man with partial priapism after blood transfusions treated successfully with LMWH....

  11. Testing of downstream catalysts for tar destruction with a guard bed in a fluidised bed biomass gasifier at pilot plant scale

    Energy Technology Data Exchange (ETDEWEB)

    Aznar, M.P.; Frances, E.; Campos, I.J.; Martin, J.A.; Gil, J. [Saragossa Univ. (Spain). Dept. of Chemistry and Environment Engineering; Corella, J. [Complutense Univ. of Madrid (Spain). Dept. of Chemical Engineering

    1996-12-31

    A new pilot plant for advanced gasification of biomass in a fast fluidised bed is now fully operative at University of Saragossa, Spain. It is a `3rd generation` pilot plant. It has been built up after having used two previous pilot plants for biomass gasification. The main characteristic of this pilot plant is that it has two catalytic reactors connected in series, downstream the biomass gasifier. Such reactors, of 4 cm i.d., are placed in a slip stream in a by-pass from the main gasifier exit gas. The gasification is made at atmospheric pressure, with flow rates of 3-50 kg/in, using steam + O{sub 2} mixtures as the gasifying agent. Several commercial Ni steam-reforming catalyst are being tested under a realistic raw gas composition. Tar eliminations or destructions higher than 99 % are easily achieved. (orig.) 2 refs.

  12. Improving Efficiency of a Counter-Current Flow Moving Bed Granular Filter

    Energy Technology Data Exchange (ETDEWEB)

    Colver, G.M.; Brown, R.C.; Shi, H.; Soo, D.S-C.

    2002-09-18

    The goal of this research is to improve the performance of moving bed granular filters for gas cleaning at high temperatures and pressures. A second goal of the research is to optimize the performances of both solids and gas filtering processes through appropriate use of granular bed materials, particle sizes, feed rates etc. in a factorial study. These goals are directed toward applications of advanced coal-fired power cycles under development by the U.S. Department of Energy including pressurized fluidized bed combustion and integrated gasification/combined cycles based on gas turbines and fuel cells. Only results for particulate gas cleaning are reported here.

  13. The influence of chlorine on the gasification of wood

    Energy Technology Data Exchange (ETDEWEB)

    Scala, C. von; Struis, R.; Stucki, S. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-06-01

    Chlorides of the heavy metals copper, lead and zinc inhibit the CO{sub 2}-gasification reaction of charcoal. This is observed either by impregnation the wood with the salts before pyrolysis or by mechanically mixing the salts with the charcoal before gasification. Charcoal impregnated or mixed with ammonium chloride reacts more slowly than untreated charcoal. Treating the charcoal with HCl also influences negatively the gasification reactivity, indicating that chlorine plays an important role in the gasification. (author) 2 figs., 4 refs.

  14. Recent advances in AFB biomass gasification pilot plant with catalytic reactors in a downstream slip flow

    Energy Technology Data Exchange (ETDEWEB)

    Aznar, M.P.; Gil, J.; Martin, J.A.; Frances, E.; Olivares, A.; Caballero, M.A.; Perez, P. [Saragossa Univ. (Spain). Dept. of Chemistry and Environment; Corella, J. [Madrid Univ. (Spain)

    1996-12-31

    A new 3rd generation pilot plant is being used for hot catalytic raw gas cleaning. It is based on a 15 cm. i.d. fluidized bed with biomass throughputs of 400-650 kg/h.m{sup 2}. Gasification is performed using mixtures of steam and oxygen. The produced gas is passed in a slip flow by two reactors in series containing a calcined dolomite and a commercial reforming catalyst. Tars are periodically sampled and analysed after the three reactors. Tar conversions of 99.99 % and a 300 % increase of the hydrogen content in the gas are obtained. (author) (2 refs.)

  15. Formation of naphthalene at gasification of biomass and hot gas cleanup with dolomite

    International Nuclear Information System (INIS)

    Tar generated at gasification of biomass and municipal wastes is an unwanted byproduct. With dolomite as catalyst the tar content is reduced to such a level as to allow final cleaning of the fuel gas with water. It is still desirable to further reduce the naphthalene level in the fuel gas. The aim of the project is to determine the influence of process variables on cracking of naphthalene with dolomite in a small fluidized bed gasifier, and to determine the influence on the content of BTX in the gas from the same variables. 10 refs, 21 figs, 1 tab

  16. Modified Thermodynamic Equilibrium Model for Biomass Gasification: A Study of the Influence of Operating Conditions

    DEFF Research Database (Denmark)

    Puig Arnavat, Maria; Bruno, Juan Carlos; Coronas, Alberto

    2012-01-01

    This paper presents a mathematical model for biomass gasification processes developed in the equation solver program Engineering Equation Solver (EES) with an implemented user-friendly interface. It is based on thermodynamic equilibrium calculations and includes some modifications to be adapted...... data from different authors for downdraft, fluidized-bed gasifiers and different biomasses, showing good agreement between reported data and modeled values. In addition, it has been used to evaluate the influence of different operating parameters [equivalence ratio (ER), air preheating, steam injection...

  17. Potential application of gasification to recycle food waste and rehabilitate acidic soil from secondary forests on degraded land in Southeast Asia.

    Science.gov (United States)

    Yang, Zhanyu; Koh, Shun Kai; Ng, Wei Cheng; Lim, Reuben C J; Tan, Hugh T W; Tong, Yen Wah; Dai, Yanjun; Chong, Clive; Wang, Chi-Hwa

    2016-05-01

    Gasification is recognized as a green technology as it can harness energy from biomass in the form of syngas without causing severe environmental impacts, yet producing valuable solid residues that can be utilized in other applications. In this study, the feasibility of co-gasification of woody biomass and food waste in different proportions was investigated using a fixed-bed downdraft gasifier. Subsequently, the capability of biochar derived from gasification of woody biomass in the rehabilitation of soil from tropical secondary forests on degraded land (adinandra belukar) was also explored through a water spinach cultivation study using soil-biochar mixtures of different ratios. Gasification of a 60:40 wood waste-food waste mixture (w/w) produced syngas with the highest lower heating value (LHV) 5.29 MJ/m(3)-approximately 0.4-4.0% higher than gasification of 70:30 or 80:20 mixtures, or pure wood waste. Meanwhile, water spinach cultivated in a 2:1 soil-biochar mixture exhibited the best growth performance in terms of height (a 4-fold increment), weight (a 10-fold increment) and leaf surface area (a 5-fold increment) after 8 weeks of cultivation, owing to the high porosity, surface area, nutrient content and alkalinity of biochar. It is concluded that gasification may be an alternative technology to food waste disposal through co-gasification with woody biomass, and that gasification derived biochar is suitable for use as an amendment for the nutrient-poor, acidic soil of adinandra belukar. PMID:26921564

  18. Coal gasification using solar energy

    Science.gov (United States)

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

    1983-01-01

    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.

  19. Plasma Treatments and Biomass Gasification

    International Nuclear Information System (INIS)

    Exploitation of forest resources for energy production includes various methods of biomass processing. Gasification is one of the ways to recover energy from biomass. Syngas produced from biomass can be used to power internal combustion engines or, after purification, to supply fuel cells. Recent studies have shown the potential to improve conventional biomass processing by coupling a plasma reactor to a pyrolysis cyclone reactor. The role of the plasma is twofold: it acts as a purification stage by reducing production of tars and aerosols, and simultaneously produces a rich hydrogen syngas. In a first part of the paper we present results obtained from plasma treatment of pyrolysis oils. The outlet gas composition is given for various types of oils obtained at different experimental conditions with a pyrolysis reactor. Given the complexity of the mixtures from processing of biomass, we present a study with methanol considered as a model molecule. This experimental method allows a first modeling approach based on a combustion kinetic model suitable to validate the coupling of plasma with conventional biomass process. The second part of the paper is summarizing results obtained through a plasma-pyrolysis reactor arrangement. The goal is to show the feasibility of this plasma-pyrolysis coupling and emphasize more fundamental studies to understand the role of the plasma in the biomass treatment processes.

  20. Solar coal gasification - Plant design and economics

    Science.gov (United States)

    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.

  1. Hydrothermal Gasification for Waste to Energy

    Science.gov (United States)

    Epps, Brenden; Laser, Mark; Choo, Yeunun

    2014-11-01

    Hydrothermal gasification is a promising technology for harvesting energy from waste streams. Applications range from straightforward waste-to-energy conversion (e.g. municipal waste processing, industrial waste processing), to water purification (e.g. oil spill cleanup, wastewater treatment), to biofuel energy systems (e.g. using algae as feedstock). Products of the gasification process are electricity, bottled syngas (H2 + CO), sequestered CO2, clean water, and inorganic solids; further chemical reactions can be used to create biofuels such as ethanol and biodiesel. We present a comparison of gasification system architectures, focusing on efficiency and economic performance metrics. Various system architectures are modeled computationally, using a model developed by the coauthors. The physical model tracks the mass of each chemical species, as well as energy conversions and transfers throughout the gasification process. The generic system model includes the feedstock, gasification reactor, heat recovery system, pressure reducing mechanical expanders, and electricity generation system. Sensitivity analysis of system performance to various process parameters is presented. A discussion of the key technological barriers and necessary innovations is also presented.

  2. Hydrogen-rich gas production via CaO sorption-enhanced steam gasification of rice husk: a modelling study.

    Science.gov (United States)

    Beheshti, Sayyed Mohsen; Ghassemi, Hojat; Shahsavan-Markadeh, Rasoul; Fremaux, Sylvain

    2015-01-01

    Gasification is a thermochemical process in which solid or liquid fuels are transformed into synthesis gas through partial oxidation. In this paper, a kinetic model of rice husk gasification has been developed, which is interesting for the applications of the syngas produced. It is a zero-dimensional, steady-state model based on global reaction kinetic, empirical correlation of pyrolysis and is capable of predicting hydrogen yield in the presence of sorbent CaO. The model can also be used as a useful tool to investigate the influence of process parameters including steam/biomass ratio, CaO/fuel ratio (CaO/Fuel), and gasification temperature on hydrogen efficiency, CO2 capture ratio (CCR), and average carbonation conversion (Save). Similar to hydrogen formation, CCR also increases with increasing CaO/Fuel, but an opposite trend is exhibited in Save. Model predictions were compared with available data from the literature, which showed fairly good agreement. PMID:25403373

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

    International Nuclear Information System (INIS)

    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

  4. Down-flow moving-bed gasifier with catalyst recycle

    Science.gov (United States)

    Halow, John S.

    1999-01-01

    The gasification of coal and other carbonaceous materials by an endothermic gasification reaction is achieved in the presence of a catalyst in a down-flow, moving-bed gasifier. Catalyst is removed along with ash from the gasifier and is then sufficiently heated in a riser/burner by the combustion of residual carbon in the ash to volatilize the catalyst. This volatilized catalyst is returned to the gasifier where it uniformly contacts and condenses on the carbonaceous material. Also, the hot gaseous combustion products resulting from the combustion of the carbon in the ash along with excess air are introduced into the gasifier for providing heat energy used in the endothermic reaction.

  5. Determination of the intrinsic reactivities for carbon dioxide gasification of rice husk chars through using random pore model.

    Science.gov (United States)

    Gao, Xiaoyan; Zhang, Yaning; Li, Bingxi; Zhao, Yijun; Jiang, Baocheng

    2016-10-01

    Rice husk is abundantly available and environmentally friendly, and char-CO2 gasification is of great importance for the biomass gasification process. The intrinsic reaction rates of carbon dioxide gasification with rice husk chars derived from different pyrolysis temperatures were investigated in this study by conducting thermogravimetric analysis (TGA) measurements. The effects of gasification temperature and reactant partial pressure on the char-CO2 gasification were investigated and the random pore model (RPM) was used to determine the intrinsic kinetic parameters based on the experimental data. The results obtained from this study show that the activation energy, reaction order and pre-exponential factor varied in the ranges of 226.65-232.28kJ/mol, 0.288-0.346 and 2.38×10(5)-2.82×10(5)1/sPa(n) for the rice husk chars pyrolyzed at 700-900°C, respectively. All the determination coefficients between the RPM predictions and experimental results were higher than 0.906, indicating the RPM is reliable for determining and evaluating the intrinsic reactivities of rice husk chars. PMID:27459684

  6. Biomass Gasification Technology Assessment: Consolidated Report

    Energy Technology Data Exchange (ETDEWEB)

    Worley, M.; Yale, J.

    2012-11-01

    Harris Group Inc. (HGI) was commissioned by the National Renewable Energy Laboratory to assess gasification and tar reforming technologies. Specifically, the assessments focused on gasification and tar reforming technologies that are capable of producing a syngas suitable for further treatment and conversion to liquid fuels. HGI gathered sufficient information to analyze three gasification and tar reforming systems. This report summarizes the equipment, general arrangement of the equipment, operating characteristics, and operating severity for each technology. The order of magnitude capital cost estimates are supported by a basis-of-estimate write-up, which is also included in this report. The report also includes Microsoft Excel workbook models, which can be used to design and price the systems. The models can be used to analyze various operating capacities and pressures. Each model produces a material balance, equipment list, capital cost estimate, equipment drawings and preliminary general arrangement drawings. Example outputs of each model are included in the Appendices.

  7. Gasification of HTGR-fuel-element-graphite as head-end process

    International Nuclear Information System (INIS)

    The process commonly favored for retention of C-14 containing HEAD-END offgas, viz. immobilization of CO2 as CaCO3 generates large waste volumes. The present work was initiated to investigate whether the waste volume decreases if the burning process is changed to one of gasification of the fuel element graphite to CO or CH4 and its subsequent decomposition to soot and the appropriate gaseous components. The experiments were carried out in a differential - fixed bed reactor under nonisothermal conditions. The results show that, at the same temperature, the reaction rate of the hydrogen-high-pressure-gasification on iron catalysts is even higher than that of the burning process. The gasification product gas (CH4) is decomposed in an integrated unit where conversion to C2H2, its decomposition, and finally the separation of soot is carried out. The use of hydrogen as process gas causes a dilution of the tritium released by the fuel elements and contamination of the gasifier offgas. It is, therefore, necessary to develop modified offgas decontamination procedures for tritium as well as krypton-85. With the proposed HEAD-END process it seems possible to decrease the waste volumes by a factor of 3 to 4 as compared with the fixation of CO2 as CaCO3. (orig.)

  8. The development of biomass gasification technology towards market penetration in China

    International Nuclear Information System (INIS)

    Biomass is the second most frequently used fuel, after coal, in China, which accounts for 20% of primary energy consumption. Though the main usage of biomass is for household cooking, the newly developed biomass gasification technology, especially the circulating fluidized bed gasification (CFBG) technology, has laid the foundations for allowing biomass gasification industry penetration into the commercial energy market. The thermal application of CFBG in wood processing factories, utilizing processing wastes to produce gaseous fuel, has been developed successfully and economically in China. The use of CFBG for generating electricity in rice mills, utilizing rice hulls with an output of 1 MW, is also underway. The status and development history of CFBG application in China is introduced in the paper. The aspects of large scale industrial application, utilization of self-produced feed material to reduce the cost of raw material, transportation problems, energy utilization combined with environmental protection etc., is discussed. The economic benefit of using CFBG for biomass and wastes towards market penetration is also presented. (author)

  9. Gasification of Empty Fruit Bunch for Hydrogen Rich Fuel Gas Production

    Directory of Open Access Journals (Sweden)

    W.A.K.G. Wan Azlina

    2011-01-01

    Full Text Available A study on gasification of Empty Fruit Bunch (EFB, a waste of the palm oil industry is investigated. The composition and particle size distribution of feedstock are determined and the thermal degradation behaviour is analysed by a thermogravimetric analysis (TGA. Then 300 g h-1 fluidized bed bench scale gasification unit is used to investigate the effect of the operating parameters on biomass gasification namely reactor temperature in the range of 700-1000C and feedstock particle size in the range of 0.3-1.0 mm. The main gas species generated, as identified by a Gas Chromatography (GC, are H2, CO, CO2 and CH4. With temperature increasing from 700 to 1000C, the total gas yield is enhanced greatly and has reached the maximum value (~ 92 wt. %, on the raw biomass sample basis at 1000C with big portions of H2 (38.02 vol.% and CO (36.36 vol.%. Feedstock particle size shows some influence on the H2, CO and CH4 yields. The feedstock particle size of 0.3 to 0.5 mm, is found to generate a higher H2 yield (33.12 vol.% and higher LHV of gas product (17.19 MJ m-3.

  10. Numerical modeling of fluidized-bed combustor

    Energy Technology Data Exchange (ETDEWEB)

    Sha, W T; Soo, S L

    1977-11-01

    Optimum design of fluidized-bed combustor requires high carbon burn-up, good sulfur retention, minimized sorbent (Ca) utilization, efficient feed distribution and mechanical layout. These parameters are strongly affected by the dynamics of the fluidized bed. The dynamic behavior of fluidized combustor is formulated in terms of multidomain - multiphase mechanics. Fluidization, bubble mechanics, coal combustion, sorbent sulfation, oxidation, solids movement and elutriation, and heat transfer are explicitly taken into account in the proposed numerical model. The model solves conservation equations of mass, momentum and energy coupled with chemical reactions as boundary value problem in space and initial value problem in time. Multi-fluid model and modified implicit multi-field numerical scheme are employed. The objective of this numerical model is for use in engineering design and scaling. Progress to date shows that all necessary relations can be incorporated within the framework of an overall multidomain - multiphase model for deterministic computation. Provisions are made for subsequent refinements of submodels of individual mechanism and improvements of the existing numerical model. These refinements and improvements can be achieved as better understanding of physical phenomena and more experimental data become available. The numerical model outlined in this report is specifically designed for the fluidized-bed combustor; however, it can readily be extended to various coal gasification systems.

  11. Production of Hydrogen from Underground Coal Gasification

    Science.gov (United States)

    Upadhye, Ravindra S.

    2008-10-07

    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.

  12. High-Btu coal gasification processes

    Energy Technology Data Exchange (ETDEWEB)

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

    1979-01-01

    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).

  13. Underground coal gasification. Gasificacion subterranea del carbon

    Energy Technology Data Exchange (ETDEWEB)

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

    1990-07-01

    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.

  14. Catalytic gasification of oil-shales

    Energy Technology Data Exchange (ETDEWEB)

    Lapidus, A.; Avakyan, T. [I.M. Gubkin Russian State Univ. of Oil and Gas, Moscow (Russian Federation); Strizhakova, Yu. [Samara State Univ. (Russian Federation)

    2012-07-01

    Nowadays, the problem of complex usage of solid fossil fuels as raw materials for obtaining of motor fuels and chemical products is becoming increasingly important. A one of possible solutions of the problem is their gasification with further processing of gaseous and liquid products. In this work we have investigated the process of thermal and catalytic gasification of Baltic and Kashpir oil-shales. We have shown that, as compared with non-catalytic process, using of nickel catalyst in the reaction increases the yield of gas, as well as hydrogen content in it, and decreases the amount of liquid products. (orig.)

  15. Pressurized pyrolysis and gasification behaviour of black liquor and biofuels

    Energy Technology Data Exchange (ETDEWEB)

    Whitty, K.; Backman, R.; Hupa, M. [Aabo Akademi, Turku (Finland)

    1996-12-01

    The objective of this project is to obtain basic experimental data on pyrolysis and gasification of various black liquors and biofuels at elevated pressures, and to model these processes. Liquor-to-liquor differences in conversion behavior of single liquor droplets during gasification at atmospheric pressure were investigated. The applicability of a rate equation developed for catalyzed gasification of carbon was investigated with regard to pressurized black liquor gasification. A neural network was developed to simulate the progression of char conversion during pressurized black liquor gasification. Pyrolysis of black liquor in a pressurized drop-tube furnace was investigated in collaboration with KTH in Stockholm. (author)

  16. Gasification of corn and clover grass in supercritical water

    Energy Technology Data Exchange (ETDEWEB)

    Pedro D' Jesus; Nikolaos Boukis; Bettina Kraushaar-Czarnetzki; Eckhard Dinjus [Chemisch-Physikalische Verfahren (ITC-CPV), Forschungszentrum Karlsruhe (Germany). Institut fuer Technische Chemie

    2006-05-15

    The influence of pressure, temperature, residence time, and alkali addition on the gasification of corn starch, clover grass and corn silage in supercritical water was investigated. Changing the pressure did not alter the gasification yield. An increase in the temperature notably improved the conversion of biomass. Residence time variations revealed that with longer residence time, gasification yield was improved until a maximum was reached. Gas composition changed with residence time and temperature. Potassium addition affected the gasification yield of corn starch, but did not influence the gasification yield of the potassium-containing natural products of clover grass and corn silage. 22 refs., 5 figs., 3 tabs.

  17. ETVS - a process for decentral processing of liquid, pasty and solid organic residues into electrical energy and ash, optionally with hydrosoft high-pressure dewatering, fluidized-bed drying, fluidized-bed gasification and heat-and-power cogeneration using product gas; ETVS - Ein Verfahren zur dezentralen Verwertung von fluessigen, pastoesen und festen biologischen Reststoffen in elektrische Energie und Asche, bedarfsweise mit Hydrosoft-Hochdruckentwaesserung, Wirbelschicht-Trockner, Wirbelschicht-Vergaser und Produktgas-Kraft-Waerme-Kopplung

    Energy Technology Data Exchange (ETDEWEB)

    Eder, C.; Eder, G. [Christian Eder Technology, Neunkirchen (Germany); Wied, E. [Bisanz GmbH, Saarbruecken (Germany)

    1999-07-01

    By means of the ETVS process, predominantly liquid organic residues can be converted into electrical energy and mineral ash decentrally, i.e. where they accrue. The process is exemplified with reference to sewage sludge. Sludge containing at least about 4 % dry residue is dewatered to the highest dry substance content possible. The obtained filter cakes are indirectly dried in a fluidized-bed drier using internal process waste heat. Then the organic sewage sludge constituents are gasified in an atmospheric fluidized bed system. The cleaned product gas is used to generate power in a cogeneration power plant, meeting the sewage treatment plant's in-house power demand. The ETVS process is self-sufficient in terms of thermal energy requirement from an initial dry substance content of the filter cake > 40 %. Incineration is a means of disposing of sewage sludge in accordance with the boundary conditions for sewage sludge disposal from 2005, laid down in the technical code on municipal waste. Combining the ETVS process with modern biological treatment stages makes for a substantial cut in the construction and operating cost of sewage treatment plants. (orig.) [German] Mit dem ETVS-Verfahren koennen ueberwiegend fluessige biologische Reststoffe dezentral, d.h. an der Anfallstelle in eigennutzbare elektrische Energie und mineralische Asche umgewandelt werden. Das Verfahren wird am Klaerschlamm beispielhaft dargestellt. Der Klaerschlamm wird ab einem Trockensubstanzgehalt von ca. 4%TR auf moeglichst hohe Trockensubstanzgehalte entwaessert und die dabei erzeugten Filterkuchen mit internen Prozessabwaermen in einem Wirbelschichttrockner indirekt getrocknet. Die organischen Bestandteile des Klaerschlammes werden anschliessend in einer ebenfalls atmosphaerischen Wirbelschichtanlage vergast. Der mit dem gereinigten Produktgas in einer KWK-Anlage erzeugte Strom wird zur Deckung des Eigenbedarfs der Klaeranlage verwandt. Durch die Veraschung liefert das ab einem

  18. Performance of entrained flow and fluidised bed biomass gasifiers on different scales

    International Nuclear Information System (INIS)

    Highlights: ► Gasification of biomass in fluidised bed and entrained flow reactors is modelled. ► The systems are evaluated for a thermal input from 10 MW to 500 MW. ► Special attention is given to the preconditioning methods for biomass. ► Fluidised bed and entrained flow gasifiers are compared in terms of efficiency and costs. - Abstract: This biomass gasification process study compares the energetic and economic efficiencies of a dual fluidised bed and an oxygen-blown entrained flow gasifier from 10 MWth to 500 MWth. While fluidised bed gasification became the most applied technology for biomass in small and medium scale facilities, entrained flow gasification technology is still used exclusively for industrial scale coal gasification. Therefore, it is analysed whether and for which capacity the entrained flow technology is an energetically and economically efficient option for the thermo-chemical conversion of biomass. Special attention is given to the pre-conditioning methods for biomass to enable the application in an entrained flow gasifier. Process chains are selected for the two gasifier types and subsequently transformed to simulation models. The simulation results show that the performance of both gasifier types is similar for the production of a pressurised product gas (2.5 MPa). The cold gas efficiency of the fluidised bed is 76–79% and about 0.5–2 percentage points higher than for the entrained flow reactor. The net efficiencies of both technologies are similar and between 64% and 71% depending on scale. The auxiliary power consumption of the entrained flow reactor is caused mainly by the air separation unit, the oxygen compression, and the fuel pulverisation, whereas the fluidised bed requires additional power mainly for gas compression. The costs for the product gas are determined as between €4.2 cent/kWh (500 MWth) and €7.4 cent/kWh (10 MWth) in the economic analysis of both technologies. The study indicates that the entrained flow

  19. Economic viability of the construction and operation of a biomass gasificator for poultry houses heating

    Energy Technology Data Exchange (ETDEWEB)

    Zanatta, Fabio Luiz; Silva, Jadir Nogueira da; Tinoco, Ilda de Fatima Ferreira; Martin, Samuel; Melo, Lucas D.; Bueno, Mateus [Universidade Federal de Vicosa (DEA/UFV), MG (Brazil). Dept. de Engenharia Agricola], E-mail: fzanatta@vicosa.ufv.br

    2008-07-01

    In all poultry farms, at least in the first days of life of the chicken, it is necessary to heat the environment to obtain a good development of the chicken and good economics results. However, this additional heat generation is sometimes neglected or not well executed, because of the costs that this practice could bring. This research has the objective of analyze the costs of construction and operation of a Biomass Gasificator for Poultry Houses Heating in comparison with a direct furnace system. The fuel used in both systems was firewood of eucalyptus. For so much, economic analyzes was make considering the costs of the gasification systems implementation in substitution of the traditional system used in the company (direct furnace system). For the viability the adopted method was the partial budget and the complementary investments were analyzed through the cash flow elaboration and of determination of indicator of economic feasibility. (author)

  20. The formation of nitrogen compounds at gasification conditions, with and without internal catalysts

    International Nuclear Information System (INIS)

    The objective of the project is to substantially decrease the emissions of nitrogen oxides from biomass IGCC by minimising the conversion of fuel nitrogen to ammonia and hydrogen cyanide in the gasification process. To reach the objective, the influence from different parameters on the formation of ammonia and hydrogen cyanide from fuel nitrogen has been studied. The parameters studied are the bed material, different functional forms for the nitrogen and the oxygen concentration. The results so far indicate that it is possible by simple methods, to influence the formation of NH3 and HCN by for example modifying the bed material, but that the functional form of the nitrogen is of minor importance. 24 refs, 7 figs, 3 tabs

  1. Clean Hydrogen Production via Novel Steam-Air Gasification of Biomass

    International Nuclear Information System (INIS)

    Gasification converts biomass into H2 and CO rich product gas by using air, oxygen and/or steam as reaction agent. An experimental and modelling study of hydrogen production was conducted using a laboratory scale counter-current fixed bed gasifier with preheated air and steam as the gasifying agents. Commercial charcoal was used as the fuel and the reactor bed was maintained at temperatures of 750-960 C by external heaters. H2 (17-28 vol%), CO (5-11 vol%) and CO2 (18-21 vol%) forms a large portion of the synthesis gas produced depending on the ratio of the gasifying agent. The experimental work was coupled with both equilibrium and kinetic modelling to predict the equilibrium composition, conversion rates and temperature profile. (authors)

  2. Costs of elephant grass gasification for rural electric power generation; Custos da gaseificacao de graminea para eletrificacao rural

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Marcelo Cortes; Sanchez, Caio Glauco; Angulo, Mario Barriga [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Mecanica. Dept. de Engenharia Termica e de Fluidos

    2000-07-01

    Biomass gasification is an sustainable option for energy supply, which presents low pollutants emission rate and allows - through the global cycle of growing and consumption of feedstock (vegetables), a balance between consumption and production of carbonic gas, preventing an increase of the carbonic gas levels in the atmosphere. Fluidized bed gasification is a means to increase the energetic use of biomass. A gasifier was built with internal diameter of 400 mm and total height of 4600 mm . The equipment was tested for gasification of elephant-grass (Pennisetum purpureum) at a 100 kg/h rate. It was evaluated an adequate diesel-electric-generator to work at hybrid regime, using 70% biomass gas and 30% diesel. With the equipment's construction costs, could be made a first economic feasibility assessment on the pilot-plant to produce electricity by grass gasification (elephant-grass) at rural communities. The annual cost of the investment was estimated. The cost of electricity was calculated as a function of the capital cost and the diesel price. The methods and equations for economic assessment are presented. This study found values between 0,16 and 0,23 R$/kWh for the produced electricity, what points towards the feasibility of this project. (author)

  3. Co-gasification of different rank coals with biomass and petroleum coke in a high-pressure reactor for H{sub 2}-rich gas production

    Energy Technology Data Exchange (ETDEWEB)

    Fermoso, J.; Arias, B.; Gil, M.V.; Plaza, M.G.; Pevida, C.; Pis, J.J.; Rubiera, F. [CSIC, Oviedo (Spain)

    2010-05-15

    Four coals of different rank were gasified, using a steam/oxygen mixture as gasifying agent, at atmospheric and elevated pressure in a fixed bed reactor fitted with a solids feeding system in continuous mode. Independently of coal rank, an increase in gasification pressure led to a decrease in H{sub 2} + CO production and carbon conversion. Gasification of the different rank Coals revealed that the higher the carbon content and reactivity, the greater the hydrogen production, co-gasification experiments of binary (coal-biomass) and ternary blends (coal-petcoke-biomass) were conducted at high pressure to study possible synergetic effects. Interactions between the blend components were found to modify the gas production. An improvement in hydrogen production and cold gas efficiency was achieved when the coal was gasified with biomass.

  4. The study of solid circulation rate in a compartmented fluidized bed gasifier (CFBG)

    Science.gov (United States)

    Wee, S. K.; Pok, Y. W.; Law, M. C.; Lee, V. C. C.

    2016-06-01

    Biomass waste has been abundantly available in Malaysia since the booming of palm oil industry. In order to tackle this issue, gasification is seen a promising technology to convert waste into energy. In view of the heat requirement for endothermic gasification reaction as well as the complex design and operation of multiple fluidized beds, compartmented fluidized bed gasifier (CFBG) with the combustor and the gasifier as separate compartments is proposed. As such, solid circulation rate (SCR) is one of the essential parameters for steady gasification and combustion to be realized in their respective compartments. Experimental and numerical studies (CFD) on the effect of static bed height, main bed aeration, riser aeration and v-valve aeration on SCR have been conducted in a cold- flow CFBG model with only river sand as the fluidizing medium. At lower operating range, the numerical simulations under-predict the SCR as compared to that of the experimental results. Also, it predicts slightly different trends over the range. On the other hand, at higher operating range, the numerical simulations are able to capture those trends as observed in the experimental results at the lower operating range. Overall, the numerical results compare reasonably well with that of the experimental works.

  5. Commercialization Development of Crop Straw Gasification Technologies in China

    Directory of Open Access Journals (Sweden)

    Zhengfeng Zhang

    2014-12-01

    Full Text Available Crop straw gasification technologies are the most promising biomass gasification technologies and have great potential to be further developed in China. However, the commercialization development of gasification technology in China is slow. In this paper, the technical reliability and practicability of crop straw gasification technologies, the economic feasibility of gas supply stations, the economic feasibility of crop straw gasification equipment manufacture enterprises and the social acceptability of crop straw gasification technologies are analyzed. The results show that presently both the atmospheric oxidation gasification technology and the carbonization pyrolysis gasification technology in China are mature and practical, and can provide fuel gas for households. However, there are still a series of problems associated with these technologies that need to be solved for the commercialization development, such as the high tar and CO content of the fuel gas. The economic feasibility of the gas supply stations is different in China. Parts of gas supply stations are unprofitable due to high initial investment, the low fuel gas price and the small numbers of consumers. In addition, the commercialization development of crop straw gasification equipment manufacture enterprises is hindered for the low market demand for gasification equipment which is related to the fund support from the government. The acceptance of the crop straw gasification technologies from both the government and the farmers in China may be a driving force of further commercialization development of the gasification technologies. Then, the crop straw gasification technologies in China have reached at the stage of pre-commercialization. At this stage, the gasification technologies are basically mature and have met many requirements of commercialization, however, some incentives are needed to encourage their further development.

  6. Surviving Bed Rest

    Science.gov (United States)

    ... doctor will give you specific information about the duration of your bed rest. continue How Does Bed ... reading about high-risk pregnancy issues, learn about breastfeeding or how to encourage your child's development instead. ...

  7. Low-temperature catalytic gasification of wet industrial wastes. FY 1991--1992 interim report

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, D.C.; Neuenschwander, G.G.; Hart, T.R.; Phelps, M.R.; Sealock, L.J. Jr.

    1993-07-01

    A catalytic gasification system operating in a pressurized water environment has been developed and refined at Pacific Northwest Laboratory (PNL) for over 12 years. Initial experiments were aimed at developing kinetics information for steam gasification of biomass in the presence of catalysts. The combined use of alkali and metal catalysts was reported for gasification of biomass and its components at low temperatures (350{degrees}C to 450{degrees}C). From the fundamental research evolved the concept of a pressurized, catalytic gasification system for converting wet biomass feedstocks to fuel gas. Extensive batch reactor testing and limited continuous reactor system (CRS) testing were undertaken in the development of this system under sponsorship of the US Department of Energy. A wide range of biomass feedstocks were tested, and the importance of the nickel metal catalyst was identified. Specific use of this process for treating food processing wastes was also studied. The concept application was further expanded to encompass cleanup of hazardous wastewater streams, and results were reported for batch reactor tests and continuous reactor tests. Ongoing work at PNL focuses on refining the catalyst and scaling the system to long-term industrial needs. The process is licensed as the Thermochemical Environmental Energy System (TEES{reg_sign}) to Onsite*Ofsite, Inc., of Duarte, California. This report is a follow-on to the 1989--90 interim report [Elliott et al. 1991], which reviewed the results of the studies conducted with a fixed-bed, continuous-feed, tubular reactor. The discussion here provides an overview of experiments on the wide range of potential feedstock materials conducted in a batch reactor; development of new catalyst materials; and tests performed in continuous-flow reactors at three scales. The appendices contain the history and background of the process development, as well as more detailed descriptions and results of the recent studies.

  8. Influence of ash composition on the sintering behavior during pressurized combustion and gasification process

    Institute of Scientific and Technical Information of China (English)

    Ni-jie JING; Qin-hui WANG; Yu-kun YANG; Le-ming CHENG; Zhong-yang LUO; Ke-fa CEN

    2012-01-01

    To determine the ash characteristics during fluidized bed combustion and gasification purposes,the investigation of the impacts of chemical composition of Jincheng coal ash on the sintering temperature was conducted.A series of experiments on the sintering behavior at 0.5 MPa was performed using the pressurized pressure-drop technique in the combustion and gasification atmospheres.Meanwhile,the mineral transformations of sintered ash pellets were observed using X-ray diffractometer (XRD) analyzer to better understand the experimental results.In addition,quantitative XRD and field emission scanning electron microscope/energy dispersive X-ray spectrometer (FE-SEM/EDS) analyses of ash samples were used for clarifying the detailed ash melting mechanism.These results show that the addition of Fe2O3 can obviously reduce the sintering temperatures under gasification atmospheres,and only affect a little the sintering temperature under combustion atmosphere.This may be due to the presence of iron-bearing minerals,which will react with other ash compositions to produce low-melting-point eutectics.The FE-SEM/EDS analyses of ash samples with Fe2O3 additive show consistent results with the XRD measurements.The CaO and Na2O can reduce the sintering temperatures under both the combustion and gasification atmospheres.This can be also contributed to the formation of low-melting-point eutectics,decreasing the sintering temperature.Moreover,the fluxing minerals,such as magnetite,anhydrite,muscovite,albite and nepheline,contribute mostly to the reduction of the sintering temperature while the feldspar minerals,such as anorthite,gehlenite and sanidine,can react with other minerals to produce low-melting-point eutectics,and thereby reduce the sintering temperatures.

  9. Study on an Integrated Sintered Metal Screen Moving Granular Bed Filter

    Institute of Scientific and Technical Information of China (English)

    吴晋沪; 王洋

    2004-01-01

    A new gas clean-up process called "integrated sintered metal screen moving granular bed" (ISMSMGB) for the integrated gasification combined cycle (IGCC) and pressured fluidized bed combustion (PFBC) was developed on the basis of a sintered metal candle filter and a cross-flow moving granular bed filter. This is a combination of the surface and deep bed filtering processes. A set of facilities was established and a series of cold model tests were carried out. The dust removal efficiency and the pressure drop of the filter were measured and analyzed. The results show that this process features the advantages of the moving bed for high capacity as well as high inlet dust load and the surface filter for high efficiency. Meanwhile, the granules moving downward cleans the cake on the screen surface, so that the system is operated at steady state.

  10. Plasma gasification of municipal solid waste

    Czech Academy of Sciences Publication Activity Database

    Hlína, Michal; Hrabovský, Milan; Konrád, Miloš

    Prague: Czech Technical University in Prague, Faculty of Electrical Engineering, 2014. s. 94. [SPPT 2014 - 26th Symposium on Plasma Physics and Technology/26./. 16.06.2014-19.06.2014, Prague] Institutional support: RVO:61389021 Keywords : Plasma * gasification * waste Subject RIV: BL - Plasma and Gas Discharge Physics

  11. Performance Analysis of an Integrated Fixed Bed Gasifier Model for Different Biomass Feedstocks

    Directory of Open Access Journals (Sweden)

    Sharmina Begum

    2013-12-01

    Full Text Available Energy recovery from biomass by gasification technology has attracted significant interest because it satisfies a key requirement of environmental sustainability by producing near zero emissions. Though it is not a new technology, studies on its integrated process simulation and analysis are limited, in particular for municipal solid waste (MSW gasification. This paper develops an integrated fixed bed gasifier model of biomass gasification using the Advanced System for Process ENngineering (Aspen Plus software for its performance analysis. A computational model was developed on the basis of Gibbs free energy minimization. The model is validated with experimental data of MSW and food waste gasification available in the literature. A reasonable agreement between measured and predicted syngas composition was found. Using the validated model, the effects of operating conditions, namely air-fuel ratio and gasifier temperature, on syngas production are studied. Performance analyses have been done for four different feedstocks, namely wood, coffee bean husks, green wastes and MSWs. The ultimate and proximate analysis data for each feedstock was used for model development. It was found that operating parameters have a significant influence on syngas composition. An air-fuel ratio of 0.3 and gasifier temperature of 700 °C provides optimum performance for a fixed bed gasifier for MSWs, wood wastes, green wastes and coffee bean husks. The developed model can be useful for gasification of other biomasses (e.g., food wastes, rice husks, poultry wastes and sugarcane bagasse to predict the syngas composition. Therefore, the study provides an integrated gasification model which can be used for different biomass feedstocks.

  12. A utilização da gaseificação de pneus usados em leito fluidizado para a produção de energéticos Gasification of used tires in fluidized bed reactor to produce energy sources

    Directory of Open Access Journals (Sweden)

    Eduardo A. Goulart

    1999-12-01

    proposal of a reactor which uses scrap tires to fuel oil using the gasification process.

  13. Process aspects in combustion and gasification Waste-to-Energy (WtE) units.

    Science.gov (United States)

    Leckner, Bo

    2015-03-01

    The utilisation of energy in waste, Waste to Energy (WtE), has become increasingly important. Waste is a wide concept, and to focus, the feedstock dealt with here is mostly municipal solid waste. It is found that combustion in grate-fired furnaces is by far the most common mode of fuel conversion compared to fluidized beds and rotary furnaces. Combinations of pyrolysis in rotary furnace or gasification in fluidized or fixed bed with high-temperature combustion are applied particularly in Japan in systems whose purpose is to melt ashes and destroy dioxins. Recently, also in Japan more emphasis is put on WtE. In countries with high heat demand, WtE in the form of heat and power can be quite efficient even in simple grate-fired systems, whereas in warm regions only electricity is generated, and for this product the efficiency of boilers (the steam data) is limited by corrosion from the flue gas. However, combination of cleaned gas from gasification with combustion provides a means to enhance the efficiency of electricity production considerably. Finally, the impact of sorting on the properties of the waste to be fed to boilers or gasifiers is discussed. The description intends to be general, but examples are mostly taken from Europe. PMID:24846797

  14. Autothermal two-stage gasification of low-density waste-derived fuels

    International Nuclear Information System (INIS)

    In order to increase the efficiency of waste utilization in thermal conversion processes, pre-treatment is advantageous. With the Herhof Stabilat[reg] process, residual domestic waste is upgraded to waste-derived fuel by means of biological drying and mechanical separation of inerts and metals. The dried and homogenized waste-derived Stabilat[reg] fuel has a relatively high calorific value and contains high volatile matter which makes it suitable for gasification. As a result of extensive mechanical treatment, the Stabilat[reg] produced is of a fluffy appearance with a low density. A two-stage gasifier, based on a parallel-arranged bubbling fluidized bed and a fixed bed reactor, has been developed to convert Stabilat[reg] into hydrogen-rich product gas. This paper focuses on the design and construction of the configured laboratory-scale gasifier and experience with its operation. The processing of low-density fluffy waste-derived fuel using small-scale equipment demands special technical solutions for the core components as well as for the peripheral equipment. These are discussed here. The operating results of Stabilat[reg] gasification are also presented

  15. Integration of energy-efficient empty fruit bunch drying with gasification/combined cycle systems

    International Nuclear Information System (INIS)

    Highlights: • Novel integrated drying, gasification and combined cycle for empty fruit bunch. • Application of enhanced process integration to achieve high total energy efficiency. • The technology covers exergy recovery and process integration. • High overall energy efficiency can be achieved (about 44% including drying). - Abstract: A high-energy-efficient process for empty fruit bunch drying with integration to gasification and combined cycle processes is proposed. The enhancement is due to greater exergy recovery and more efficient process integration. Basically, the energy/heat involved in a single process is recovered as much as possible, leading to minimization of exergy destruction. In addition, the unrecoverable energy/heat is utilized for other processes through process integration. During drying, a fluidized bed dryer with superheated steam is used as the main evaporator. Exergy recovery is performed through exergy elevation via compression and effective heat coupling in a dryer and heat exchangers. The dried empty fruit bunches are gasified in a fluidized bed gasifier using air as the fluidizing gas. Furthermore, the produced syngas is utilized as fuel in the combined cycle module. From process analysis, the proposed integrated processes can achieve a relatively high energy efficiency. Compared to a standalone drying process employing exergy recovery, the proposed integrated drying can reduce consumed energy by about 1/3. In addition, the overall integrated processes can reach a total power generation efficiency of about 44%

  16. Rapid toxicity screening of gasification ashes.

    Science.gov (United States)

    Zhen, Xu; Rong, Le; Ng, Wei Cheng; Ong, Cynthia; Baeg, Gyeong Hun; Zhang, Wenlin; Lee, Si Ni; Li, Sam Fong Yau; Dai, Yanjun; Tong, Yen Wah; Neoh, Koon Gee; Wang, Chi-Hwa

    2016-04-01

    The solid residues including bottom ashes and fly ashes produced by waste gasification technology could be reused as secondary raw materials. However, the applications and utilizations of these ashes are very often restricted by their toxicity. Therefore, toxicity screening of ash is the primary condition for reusing the ash. In this manuscript, we establish a standard for rapid screening of gasification ashes on the basis of in vitro and in vivo testing, and henceforth guide the proper disposal of the ashes. We used three different test models comprising human cell lines (liver and lung cells), Drosophila melanogaster and Daphnia magna to examine the toxicity of six different types of ashes. For each ash, different leachate concentrations were used to examine the toxicity, with C0 being the original extracted leachate concentration, while C/C0 being subsequent diluted concentrations. The IC50 for each leachate was also quantified for use as an index to classify toxicity levels. The results demonstrated that the toxicity evaluation of different types of ashes using different models is consistent with each other. As the different models show consistent qualitative results, we chose one or two of the models (liver cells or lung cells models) as the standard for rapid toxicity screening of gasification ashes. We may classify the gasification ashes into three categories according to the IC50, 24h value on liver cells or lung cells models, namely "toxic level I" (IC50, 24h>C/C0=0.5), "toxic level II" (C/C0=0.05types of ashes generated in gasification plants every day. Subsequently, appropriate disposal methods can be recommended for each toxicity category. PMID:26923299

  17. Gasification of oil shale by solar energy

    International Nuclear Information System (INIS)

    Gasification of oil shales followed by catalytic reforming can yield synthetic gas, which is easily transportable and may be used as a heat source or for producing liquid fuels. The aim of the present work was to study the gasification of oil shales by solar radiation, as a mean of combining these two energy resources. Such a combination results in maximizing the extractable fuel from the shale, as well as enabling us to store solar energy in a chemical bond. In this research special attention was focused upon the question of the possible enhancement of the gasification by direct solar irradiation of the solid carbonaceous feed stock. The oil shale served here as a model feedstock foe other resources such as coal, heavy fuels or biomass all of which can be gasified in the same manner. The experiments were performed at the Weizman institute's solar central receiver, using solar concentrated flux as an energy source for the gasification. The original contributions of this work are : 1) Experimental evidence is presented that concentrated sunlight can be used effectively to carry out highly endothermic chemical reactions in solid particles, which in turn forms an essential element in the open-loop solar chemical heat pipe; 2) The solar-driven gasification of oil shales can be executed with good conversion efficiencies, as well as high synthesis gas yields; 3)There was found substantial increase in deliverable energy compared to the conventional retorting of oil shales, and considerable reduction in the resulting spent shale. 5) A detailed computer model that incorporates all the principal optical and thermal components of the solar concentrator and the chemical reactor has been developed and compared favorably against experimental data. (author)

  18. Partial priapism

    DEFF Research Database (Denmark)

    Hoyerup, Peter; Azawi, Nessn Htum

    2013-01-01

    With only 34 prior cases in world literature, partial priapism (PP), also called partial segmental thrombosis of the corpus cavernosum, is a rare urological condition. The aetiology and treatment of PP is still unclear, but bicycle riding, trauma, drug usage, sexual intercourse, haematological...... diseases and α-blockers have been associated with PP. In this case report and world literature review, we describe the case of a 50-year-old man suffering from PP after ingesting 100 mg of sildenafil. The patient was treated with a surgical incision for corpus cavernosum and clot evacuation, as a...

  19. Process modeling and thermodynamic analysis of Lurgi fixed-bed coal gasifier in an SNG plant

    International Nuclear Information System (INIS)

    Highlights: • A comprehensive model is proposed for the Lurgi fixed-bed gasifier. • A strategy is proposed to accelerate the convergence of the model solutions. • Satisfactory agreement between model predictions and industrial data is obtained. • An exergy analysis is applied to both the Lurgi gasifier and the gasification system. - Abstract: This paper presents a comprehensive steady state kinetic model of a commercial-scale pressurized Lurgi fixed-bed dry bottom coal gasifier. The model is developed using the simulator Aspen Plus. Five sequential modules: drying zone, pyrolysis zone, gasification zone, combustion zone and overall heat recovery unit, are considered in the main process model. A non-linear programming (NLP) model is employed to estimate the pyrolysis products, which include char, coal gas and high-weight hydrocarbons/distillable liquids (tar, phenol, naphtha and oil). To accelerate solution convergence, an external FORTRAN subroutine is used to simulate the kinetics of the combustion and gasification processes which are formulated in terms of a series of continuous stirred-tank reactors. The model is validated with industrial data. The effects of two key operating parameters, namely oxygen/coal mass ratio and steam/coal mass ratio, on the thermodynamic efficiencies of the Lurgi gasifier and the gasification system as a whole are investigated via extensive simulation studies

  20. Techno-Economic Analysis of Biofuels Production Based on Gasification

    Energy Technology Data Exchange (ETDEWEB)

    Swanson, R. M.; Platon, A.; Satrio, J. A.; Brown, R. C.; Hsu, D. D.

    2010-11-01

    This study compares capital and production costs of two biomass-to-liquid production plants based on gasification. The first biorefinery scenario is an oxygen-fed, low-temperature (870?C), non-slagging, fluidized bed gasifier. The second scenario is an oxygen-fed, high-temperature (1,300?C), slagging, entrained flow gasifier. Both are followed by catalytic Fischer-Tropsch synthesis and hydroprocessing to naphtha-range (gasoline blend stock) and distillate-range (diesel blend stock) liquid fractions. Process modeling software (Aspen Plus) is utilized to organize the mass and energy streams and cost estimation software is used to generate equipment costs. Economic analysis is performed to estimate the capital investment and operating costs. Results show that the total capital investment required for nth plant scenarios is $610 million and $500 million for high-temperature and low-temperature scenarios, respectively. Product value (PV) for the high-temperature and low-temperature scenarios is estimated to be $4.30 and $4.80 per gallon of gasoline equivalent (GGE), respectively, based on a feedstock cost of $75 per dry short ton. Sensitivity analysis is also performed on process and economic parameters. This analysis shows that total capital investment and feedstock cost are among the most influential parameters affecting the PV.

  1. DIFFUSION COATINGS FOR CORROSION RESISTANT COMPONENTS IN COAL GASIFICATION SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Gopala N. Krishnan; Ripudaman Malhotra; Angel Sanjurjo

    2004-05-01

    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.

  2. A continuous two stage solar coal gasification system

    Science.gov (United States)

    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.

  3. Project Thunderbird: a nuclear trigger for coal gasification

    International Nuclear Information System (INIS)

    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

  4. DEVELOPMENT OF A NANO-Ni-La-Fe/Al2O3 CATALYST TO BE USED FOR SYN-GAS PRODUCTION AND TAR REMOVAL AFTER BIOMASS GASIFICATION

    Directory of Open Access Journals (Sweden)

    Jianfen Li

    2009-11-01

    Full Text Available The objective of this study was to develop a supported tri-metallic catalyst (nano-Ni-La-Fe/γ-Al2O3 for tar removal in biomass steam gasification, to significantly enhance the quality of the produced gas. For this purpose, the supported tri-metallic catalysts were prepared by a deposition-precipitation (DP method. Different analytical approaches were used to characterize the synthesized catalysts. The results showed that the prepared tri-metallic catalysts had an egg-shell structure with a specific surface area of 214.7 m2/g. The activity of the catalysts for gas production and tar removal in the process of biomass gasification was also investigated using a bench-scale combined fixed bed reactor. The experiments indicated that the tar yield after adding catalyst was reduced significantly and the efficiency of tar removal reached 99% for the biomass steam gasification at 800oC, while the gas yield after adding catalysts increased markedly and less coke was found over the catalyst. Meanwhile, the compositions of gas products before and after adding catalyst in the process also changed significantly; in particular, the content of hydrogen in catalytic steam gasification was improved by over 10 vol%. Therefore, using the prepared tri-metallic catalyst in biomass gasification can significantly improve the quality of the produced gas and efficiently eliminate the tar generation, preventing coke deposition on the catalyst surfaces, thus demonstrating a long lifetime of the catalyst.

  5. Top Ten Bed Bug Tips

    Science.gov (United States)

    ... have bed bugs, not fleas, ticks or other insects. You can compare your insect to the pictures on our Identifying bed bugs ... bedbugs Bed Bugs Home Learn about Bed Bugs — Characteristics of Bed Bugs — Finding Bed Bugs Protecting Your ...

  6. Analysis of Operation Parameters in a Dual Fluidized Bed Biomass Gasifier Integrated with a Biomass Rotary Dryer: Development and Application of a System Model

    Directory of Open Access Journals (Sweden)

    Nargess Puadian

    2014-07-01

    Full Text Available An integrated system model was developed in UniSim Design for a dual fluidized bed (DFB biomass gasifier and a rotary biomass dryer using a combination of user-defined and built-in unit operations. A quasi-equilibrium model was used for modelling biomass steam gasification in the DFB gasifier. The biomass drying was simulated with consideration of mass and energy balances, heat transfer, and dryer’s configuration. After validation using experimental data, the developed system model was applied to investigate: (1 the effects of gasification temperature and steam to biomass (S/B ratio on the gasification performance; (2 the effect of air supplied to the fast fluidized bed (FFB reactor and feed biomass moisture content on the integrated system performance, energy and exergy efficiencies. It was found that gasification temperature and S/B ratio have positive effects on the gasification yields; a H2/CO ratio of 1.9 can be achieved at the gasification temperature of 850 °C with a S/B ratio of 1.2. Consumption of excessive fuel in the system at higher biomass feed moisture content can be compensated by the heat recovery such as steam generation while it has adverse impact on exergy efficiency of the system.

  7. Schemes and New Developments in Combinations of Gasification with Fuel Gas Cleaning for Power Generation in Piston Gas Engines and Gas Turbines

    OpenAIRE

    Skoblia, S.

    2013-01-01

    In the contribution, possibilities are presented and discussed in details, how to employ the internal combustion engines and gas (combustion) turbines or their suitable combination for producing the electric power and heat from the gas produced by the partial oxidation (gasification) of biomass and alternative solid fuels.

  8. Effect of reactions in small eddies on biomass gasification with eddy dissipation concept - Sub-grid scale reaction model.

    Science.gov (United States)

    Chen, Juhui; Yin, Weijie; Wang, Shuai; Meng, Cheng; Li, Jiuru; Qin, Bai; Yu, Guangbin

    2016-07-01

    Large-eddy simulation (LES) approach is used for gas turbulence, and eddy dissipation concept (EDC)-sub-grid scale (SGS) reaction model is employed for reactions in small eddies. The simulated gas molar fractions are in better agreement with experimental data with EDC-SGS reaction model. The effect of reactions in small eddies on biomass gasification is emphatically analyzed with EDC-SGS reaction model. The distributions of the SGS reaction rates which represent the reactions in small eddies with particles concentration and temperature are analyzed. The distributions of SGS reaction rates have the similar trend with those of total reactions rates and the values account for about 15% of the total reactions rates. The heterogeneous reaction rates with EDC-SGS reaction model are also improved during the biomass gasification process in bubbling fluidized bed. PMID:27010338

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1978-10-01

    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.

  10. PFB air gasification of biomass. Investigation of product formation and problematic issues related to ammonia, tar and alkali

    Energy Technology Data Exchange (ETDEWEB)

    Padban, Nader

    2000-09-01

    Fluidised bed thermal gasification of biomass is an effective route that results in 100 % conversion of the fuel. In contrast to chemical, enzymatic or anaerobic methods of biomass treatment, the thermal conversion leaves no contaminated residue after the process. The product gas evolved within thermal conversion can be used in several applications such as: fuel for gas turbines, combustion engines and fuel cells, and raw material for production of chemicals and synthetic liquid fuels. This thesis treats a part of the experimental data from two different gasifiers: a 90 kW{sub th} pressurised fluidised bubbling bed gasifier at Lund University and a 18 MW{sub th} circulating fluidised bed gasifier integrated with gas turbine (IGCC) in Vaernamo. A series of parallel and consecutive chemical reactions is involved in thermal gasification, giving origin to formation of a variety of products. These products can be classified within three major groups: gases, tars and oils, and char. The proportion of these categories of species in the final product is a matter of the gasifier design and the process parameters. The thesis addresses the technical and theoretical aspects of the biomass thermochemical conversion and presents a new approach in describing the gasification reactions. There is an evidence of fuel effect on the characteristics of the final products: a mixture of plastic waste (polyethylene) and biomass results in higher concentration of linear hydrocarbons in the gas than gasification of pure biomass. Mixing the biomass with textile waste (containing aromatic structure) results in a high degree of formation of aromatic compounds and light tars. Three topic questions within biomass gasification, namely: tar, NO{sub x} and alkali are discussed in the thesis. The experimental results show that gasification at high ER or high temperature decreases the total amount of the tars and simultaneously reduces the contents of the oxygenated and alkyl-substituted poly

  11. VERIFICATION AND COMPARISON OF FORMULAS FOR BED LOAD TRANSPORT

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Several typical formulas for bed load transport are examinedbased on field data in this paper. It is concluded that, the Einstein formula provides good estimates for the bed load transport rate while other ones predict much lower transport rates. The main reason for the under-prediction is that Dp, the effective diameter of particles, is too large as a representative diameter of the bed material for gravel streams with partially movable bed. Performance of these formulas can be significantly improved if D35 is adopted instead of Dp.

  12. 78 FR 43870 - Hydrogen Energy California's Integrated Gasification Combined Cycle Project; Preliminary Staff...

    Science.gov (United States)

    2013-07-22

    ... of Availability Hydrogen Energy California's Integrated Gasification Combined Cycle Project... availability of the Hydrogen Energy California's Integrated Gasification Combined Cycle Project Preliminary... the Hydrogen Energy California's (HECA) Integrated Gasification Combined Cycle Project, which would...

  13. Roadmap for the commercialisation of biomass gasification. A critical evaluation, tips, questions and pitfalls

    International Nuclear Information System (INIS)

    Biomass has the potential to be a major replacement of fossil fuels. The world wide availability of biomass is considerable but it is not always in balance with the anticipated consumption. Biomass (wood) has the disadvantage that it has a low energy density and transport costs are, therefore, relatively high. Combustion, being a well-developed technology with many references, is the obvious choice for conversion technology. On the scale that biomass plants are usually constructed, however, the overall efficiency of the combustion system is low. Gasification has the advantage that solid fuel is converted into gaseous fuel which can be used in IC (internal combustion) engines or combined (gas and steam turbine) cycles with high efficiency. Even on a very small scale (several hundred kWe) a biomass-driven IC engine can have an efficiency of around 25%. Gasification has not yet advanced to the stage that it can serve as a reliable conversion technology for supplying electric power to industry or to the national grid. This may be possible on paper but in practice the market needs to be convinced by the success of plants in full operation. The first generation of plants, now under construction, or in operation, have to demonstrate the technology and provide confidence for future developments. Fixed bed gasification in combination with IC engines is more appropriate for small units. The development in micropower units is of particular interest. This development has been initiated for natural gas-fuelled units supplying power and heat to households, apartment blocks or offices. Once the fuel handling problems have been overcome and the units are more reliable and easier to operate, this could be a market with ample cost savings on the basis of mass production. Fluidised bed gasification, integrated with a combined cycle, is probably better suited to larger units, above 10 MWe. After experience has been obtained with units at an atmospheric pressure, the increase of the

  14. GASIFICATION TEST RUN TC06

    Energy Technology Data Exchange (ETDEWEB)

    Southern Company Services, Inc.

    2003-08-01

    This report discusses test campaign TC06 of the Kellogg Brown & Root, Inc. (KBR) Transport Reactor train with a Siemens Westinghouse Power Corporation (Siemens Westinghouse) particle filter system at the Power Systems Development Facility (PSDF) located in Wilsonville, Alabama. The Transport Reactor is an advanced circulating fluidized-bed reactor designed to operate as either a combustor or a gasifier using a particulate control device (PCD). The Transport Reactor was operated as a pressurized gasifier during TC06. Test run TC06 was started on July 4, 2001, and completed on September 24, 2001, with an interruption in service between July 25, 2001, and August 19, 2001, due to a filter element failure in the PCD caused by abnormal operating conditions while tuning the main air compressor. The reactor temperature was varied between 1,725 and 1,825 F at pressures from 190 to 230 psig. In TC06, 1,214 hours of solid circulation and 1,025 hours of coal feed were attained with 797 hours of coal feed after the filter element failure. Both reactor and PCD operations were stable during the test run with a stable baseline pressure drop. Due to its length and stability, the TC06 test run provided valuable data necessary to analyze long-term reactor operations and to identify necessary modifications to improve equipment and process performance as well as progressing the goal of many thousands of hours of filter element exposure.

  15. Reaction kinetics of solid fuels during entrained flow gasification

    Energy Technology Data Exchange (ETDEWEB)

    Tremel, Alexander

    2012-10-24

    Despite the application of entrained flow gasification on larger scales, the reaction rates in the hot conversion zone are almost unknown. But the knowledge of the rates of the gasification reactions at high temperature and high pressure is crucial for the detailed design and optimisation of these gasifiers. This dissertation provides measurements of fuel conversion under operation conditions relevant to industrial gasifiers and aims at the transfer of the data to larger scale applications. A novel pilot-scale research reactor is developed that enables the study of gasification reactions at high temperature, high pressure and under entrained flow conditions. The Pressurised High Temperature Entrained Flow Reactor (PiTER) is operated at up to 1600 C and 4.0 MPa in pyrolysis and gasification experiments. The data set is extended by measurements in an atmospheric entrained flow reactor and a pressurised wire mesh reactor. Devolatilisation and gasification behaviour of a wide range of fuels is analysed including anthracite, bituminous coal, lignite, biocoal (from hydrothermal carbonisation), and biomass; however, Rhenish lignite is used in most of the experiments. The pyrolysis data enable the validation of a simple first order reaction model that describes the influence of pressure, temperature, and residence time on volatile yield. Char samples collected from the three reactors are analysed using laboratory procedures and bench-scale setups. Specific char surface area is measured by CO{sub 2} adsorption at 273 K, and is found to be significantly influenced by char conversion, reaction temperature, and devolatilisation pressure. The surface data are described by an extension of the Random Pore Model. Intrinsic char reactivity is measured in a pressurised thermogravimetric analyser and the influence of reactant partial pressure and temperature on the char-CO{sub 2} and char-H{sub 2}O reaction is studied. The intrinsic reaction rate is described by nth order and

  16. Physical property behaviour of North Dakota lignite in an oxygen/steam blown moving bed gasifier

    OpenAIRE

    Mangena, S.J.; Bunt, J.R.; Waanders, F.B.

    2013-01-01

    In this study lignite originating from North Dakota (USA) was thermally treated in an oxygen/steam blown commercial-scale moving bed gasifier operating on lump coal at the Dakota Gasification Company (DGC) in order to identify the physical property changes that occur during heating. After reaction, the solid particulate remnants were extracted from the reactor and characterised using standard techniques. Thermal fragmentation was found to be severe with the coal tested, i.e. the l...

  17. Characteristics of cardboard and paper gasification with CO2

    International Nuclear Information System (INIS)

    Evolutionary behavior of syngas chemical composition and yield have been examined for paper and cardboard at three different temperatures of 800, 900 and 1000 °C using CO2 as the gasifying agent at constant flow rate. Specifically the evolution of syngas chemical composition with time has been investigated. Pyrolysis of the sample was dominant at the beginning of the gasification process as observed from the high initial devolatilization of the sample followed by char gasification of material to form syngas for a long period of time. Results provided the role of gasification temperature on kinetics of the CO2 gasification process. Increase in gasification temperature provided increased conversion of the sample material to syngas. Thus the sample conversion to syngas was low at the low temperature of 800 °C while at elevated temperatures of 900 and 1000 °C substantial enhancement of the kinetics process occurred. The evolution of extensive reaction rate of carbon-monoxide was calculated. Results show that increase in temperature increased the extensive reaction rate of carbon-monoxide. The global behavior of syngas chemical composition examined at three different temperatures revealed a peak in concentration of H2 to exhibit after few minutes into the gasification that changed with gasification temperature. At 800 °C gasification temperature peak in H2 was displayed at 3 min into gasification while it decreased to only 2 min, approximately, at gasification temperatures of 900 and 1000 °C. The effect of reactor temperature on CO mole fraction has also been examined. Increase in the gasification temperature enhances the mole fraction of CO yields. This is attributed to the increase in forward reaction rate of the Boudouard reaction (C+CO2↔2CO). The results show important role of CO2 gas for the gasification of wastes and low grade fuels to clean syngas.

  18. Study on Semi-Gasification Combustion Technology of Stover

    OpenAIRE

    Zhao Qing-Ling; Chen Fu-Jin; Wang Yang-Yang; Zhang Bai-Liang

    2013-01-01

    In order to develop a mechanism of clean and efficient combustion, this study studied the combustion mechanism of stover semi-gasification by a clean stove designed. The experimental material was corn Stover briquettes. Process of semi-gasification combustion can be divided into two parts: gasification stage and combustion stage. First, under the low primary air amount, stover gives off partly combustible gas (Volatile matter). Then, the combustible gas rises and burns in the upper Furnace wh...

  19. PYROLYSIS AND GASIFICATION OF MUNICIPAL AND INDUSTRIAL WASTES BLENDS

    OpenAIRE

    Martino Paolucci; Paolo De Filippis; Carlo Borgianni

    2010-01-01

    Gasification could play an important role in the treatment of municipal solid wastes. However, some problems may arise when using unsorted materials due to the difficulties of obtaining a feed with consistent physical characteristics and chemical properties. To overcome this problem, a new type of gasifier consisting of three stages, namely a pyrolytic stage followed by gasification and a reforming stage, was considered. Theoretical calculations made on the proposed gasification scheme shows ...

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

    OpenAIRE

    Marina Sidorová; Gabriel Wittenberger

    2006-01-01

    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...

  1. Basic equations of channel model for underground coal gasification

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    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.

  2. Feasibility study of gasification of oil palm fronds

    OpenAIRE

    Sulaiman, S. A.; S. Balamohan; M.N.Z. Moni; S.M. Atnaw; Mohamed, A. O.

    2015-01-01

    Considering the large and consistent supply, oil palm fronds could be a promising source of biomass energy through gasification. There is very scarce information on the characteristics of oil palm fronds, which is vital in deciding if such biomass is technically suitable for gasification. In the present work, the feasibility of oil palm fronds for biomass gasification is studied. The study is conducted experimentally via standard tests to determine their thermochemical characteristics. Ultim...

  3. Radial voidage variation in fixed beds of fuel wood pellets

    International Nuclear Information System (INIS)

    Fixed beds of fuel wood are commonly found in numerous processes: storage and transportation, drying and thermal conversion such as combustion or gasification. Pellets in particular are mostly used as fuel for domestic heating boilers. The characterization of spatial voidage distribution is of great importance for flow and reactor modelling. The present study focuses on the radial porosity variations of cylindrical beds of commercially available wood pellets. The experimental procedure is based on the classical technique of consolidating packed beds with a resin. The radial voidage distribution of three different cylindrical beds is determined by image analysis of sections of the solidified packing. The results are discussed and summarized in a mathematical expression correlating the radial voidage distribution depending on packing core porosity and dimensionless distance from the tube wall. -- Highlights: ► Packing characteristics for commercially available wood pellets were investigated. ► Radial porosity variations of cylindrical pellets beds were investigated. ► Epoxy resin consolidated packings were investigated by image analysis. ► Mathematical term for radial voidage distribution of pellet packing was derived.

  4. Pyrolysis and Gasification of Solid, Organic, Low-Level Nuclear Waste: HDPE as a Case Study

    International Nuclear Information System (INIS)

    As environmental concerns have become a high priority matter, treatment of waste and especially radioactive waste are considered as a big global issue. The Israeli national radioactive waste disposal site is situated at the Nuclear Research Center Negev (NRCN). Radioactive waste from hospitals, research institutions and industry is delivered to the site. Pyrolysis is the thermochemical decomposition process of organic materials in the absence of oxygen to produce char, pyrolysis oil and gas. Gasification is defined as the thermal, non combustion, decomposition of organic material with a limited amount of oxygen and/or steam. Both processes are considered today as advanced thermal treatment technologies leading to mass and volume reduction of radioactive/hazardous organic waste, while retaining the radionuclides and inorganic material in solid form to be further disposed. In the present study, the thermal decomposition of High Density Poly-Ethylene (HDPE) was investigated combining two experimental systems. Thermo-Gravimetric Analysis (TGA) was used to measure the maximal decomposition rates at different pyrolytic experimental conditions and obtain the activation energy of the decomposition reaction. Product distribution and the extent of conversion to gas under pyrolytic and partial oxidating conditions (gasification) have been obtained from experiments performed in the pyrolysis/gasification system. Gas analysis was performed using Gas Chromatography (GC).

  5. Robustness studies on coal gasification process variables

    Directory of Open Access Journals (Sweden)

    RLJ Coetzer

    2004-12-01

    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.

  6. Coal gasification: technology for the power industry

    Energy Technology Data Exchange (ETDEWEB)

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

    1994-01-01

    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. Gasification characteristics of auto shredder residue

    International Nuclear Information System (INIS)

    Given the large volume of used tyre waste generated each year it is imperative that suitable re-use and disposal techniques are developed for dealing with this problem; presently these include rethreading, reprocessing for use as safe playground and sports surfaces, use as noise reduction barriers and utilisation as a fuel source. This paper reports on pilot scale studies designed to investigate the suitability of automotive waste for energy recovery via gasification. The study was carried out into auto shredder residue, which is a mixture of three distinct waste streams: tyres, rubber/plastic and general automotive waste. The tests included proximate, ultimate and elemental analysis, TGA, as well as calorific value determinations. In addition, the waste was tested in a desktop gasifier, and analysis was carried out to determine the presence and type of combustible gases. It was concluded that tyre waste and rubber/plastic waste are quite suitable fuels for gasification. (author)

  8. Wood biomass gasification: Technology assessment and prospects in developing countries

    International Nuclear Information System (INIS)

    This investigation of the technical-economic feasibility of the development and use of wood biomass gasification plants to help meet the energy requirements of developing countries covers the following aspects: resource availability and production; gasification technologies and biomass gasification plant typology; plant operating, maintenance and safety requirements; the use of the biomass derived gas in internal combustion engines and boilers; and the nature of energy requirements in developing countries. The paper concludes with a progress report on biomass gasification research programs being carried out in developing countries world-wide

  9. Thermal Plasma Gasification of Organic Waste

    Czech Academy of Sciences Publication Activity Database

    Hrabovský, Milan; Hlína, Michal; Konrád, Miloš; Kopecký, Vladimír; Kavka, Tetyana; Chumak, Oleksiy; Mašláni, Alan

    Heilbronn: Institute of Space Propulsion, German Aerospace Center, 2010, s. 89-90. ISBN N. [International Workshop and Exhibition on Plasma Assisted Combustion/6th./. Heilbronn (DE), 13.09.2010-15.09.2010] R&D Projects: GA ČR GA202/08/1084 Institutional research plan: CEZ:AV0Z20430508 Keywords : DC arc plasma torch * plasma gasification * organic waste * synthesis gas Subject RIV: BL - Plasma and Gas Discharge Physics

  10. High temperature steam gasification of wastewater sludge

    International Nuclear Information System (INIS)

    High temperature steam gasification is one of the most promising, viable, effective and efficient technology for clean conversion of wastes to energy with minimal or negligible environmental impact. Gasification can add value by transforming the waste to low or medium heating value fuel which can be used as a source of clean energy or co-fired with other fuels in current power systems. Wastewater sludge is a good source of sustainable fuel after fuel reforming with steam gasification. The use of steam is shown to provide value added characteristics to the sewage sludge with increased hydrogen content as well total energy. Results obtained on the syngas properties from sewage sludge are presented here at various steam to carbon ratios at a reactor temperature of 1173 K. Effect of steam to carbon ratio on syngas properties are evaluated with specific focus on the amounts of syngas yield, syngas composition, hydrogen yield, energy yield, and apparent thermal efficiency. The apparent thermal efficiency is similar to cold gas efficiency used in industry and was determined from the ratio of energy in syngas to energy in the solid sewage sludge feedstock. A laboratory scale semi-batch type gasifier was used to determine the evolutionary behavior of the syngas properties using calibrated experiments and diagnostic facilities. Results showed an optimum steam to carbon ratio of 5.62 for the range of conditions examined here for syngas yield, hydrogen yield, energy yield and energy ratio of syngas to sewage sludge fuel. The results show that steam gasification provided 25% increase in energy yield as compared to pyrolysis at the same temperature.

  11. Gasification of biomass in thermal plasma

    Czech Academy of Sciences Publication Activity Database

    Hrabovský, Milan

    Vol. 2. Brno: University of Technology Brno, 2007 - (Aubrecht, V.; Bartlová, M.), s. 7-16 ISBN 978-80-214-3369-4. [Symposium on Physics of Switching Arc/17th./. Brno (CZ), 10.09.2007-13.09.2007] R&D Projects: GA ČR GA202/05/0669 Institutional research plan: CEZ:AV0Z20430508 Keywords : Biomass * gasification * thermal plasma Subject RIV: BL - Plasma and Gas Discharge Physics

  12. Plasma pyrolysis and gasification of biomass

    Czech Academy of Sciences Publication Activity Database

    Hrabovský, Milan

    Beijing: Hefei Institutes of Physical Science, CAS, 2008. s. 33-33. [Asia-Pacific Conference on Plasma Science and Technology APCPST 9/9th./. 08.11.2008-11.11.2008, Huangshan] R&D Projects: GA ČR GA202/08/1084 Institutional research plan: CEZ:AV0Z20430508 Keywords : Thermal plasma * biomass * gasification Subject RIV: BL - Plasma and Gas Discharge Physics

  13. THERMODYNAMIC ANALYSIS OF BLACK LIQUOR STEAM GASIFICATION

    OpenAIRE

    Shri Ramaswamy Mail; Hua-Jiang Huang

    2011-01-01

    Pulp and paper mills represent a major platform for the use of abundant, renewable forest-based biomass as raw material. The pulping processes produce a large amount of black liquor solids, which is currently burnt in a conventional Tomlinson recovery boiler for recovery of energy and inorganic chemicals. This combustion technology can recover chemicals with good efficiency, and steam and power can be produced for the mills. However, Black Liquor Gasification (BLG) can be used to substitute f...

  14. Biomass Gasification and High Temperature Gas Cleaning

    Czech Academy of Sciences Publication Activity Database

    Hejdová, Petra; Solich, M.; Vosecký, Martin; Malecha, J.; Koutský, B.; Punčochář, Miroslav; Skoblia, Sergej

    -: -, 2005, s. 221-224. ISBN 80-8073-382-1. [New Trends in Technology Systems Operation'05. Prešov (SK), 20.11.2005-21.11.2005] R&D Projects: GA ČR(CZ) GA104/04/0829 Institutional research plan: CEZ:AV0Z40720504 Keywords : biomass and waste * gasification * hot gas cleaning Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  15. Plasma gasification of waste organics and biomass

    Czech Academy of Sciences Publication Activity Database

    Hrabovský, Milan

    Brno: Masaryk University, 2008. s. 42-43. ISBN N. [Central European Symposium on Plasma Chemistry/2nd./. 31.08.2008-04.09.2008, Brno] R&D Projects: GA ČR GA202/08/1084 Institutional research plan: CEZ:AV0Z20430508 Source of funding: R - rámcový projekt EK Keywords : Thermal plasma * biomass * gasification Subject RIV: BL - Plasma and Gas Discharge Physics

  16. Development of catalytic gas cleaning in gasification

    Energy Technology Data Exchange (ETDEWEB)

    Simell, P.; Kurkela, E.; Staahlberg, P.; Hepola, J. [VTT Energy, Espoo (Finland)

    1996-12-31

    Gasification gas containing dust can be efficiently purified from tars and ammonia with a nickel monolith catalyst. Temperatures of >900 deg C and a residence time of about 1 s (SV 2 500 1/h) were needed at 5 bar pressure to achieve complete tar decomposition and 80 % ammonia conversion. Catalyst deactivation was not observed during test runs of 100 h. At lower pressures dolomites and limestones can also be applied for tar removal at about 900 deg C temperatures. (orig.) 12 refs.

  17. System studies on Biofuel production via Integrated Biomass Gasification

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Jim; Lundgren, Joakim [Luleaa Univ. of Technology Bio4Energy, Luleaa (Sweden); Malek, Laura; Hulteberg, Christian [Lund Univ., Lund (Sweden); Pettersson, Karin [Chalmers Univ. of Technology, Goeteborg (Sweden); Wetterlund, Elisabeth [Linkoeping Univ. Linkoeping (Sweden)

    2013-09-01

    A large number of national and international techno-economic studies on industrially integrated gasifiers for production of biofuels have been published during the recent years. These studies comprise different types of gasifiers (fluidized bed, indirect and entrained flow) integrated in different industries for the production of various types of chemicals and transportation fuels (SNG, FT-products, methanol, DME etc.) The results are often used for techno-economic comparisons between different biorefinery concepts. One relatively common observation is that even if the applied technology and the produced biofuel are the same, the results of the techno-economic studies may differ significantly. The main objective of this project has been to perform a comprehensive review of publications regarding industrially integrated biomass gasifiers for motor fuel production. The purposes have been to identify and highlight the main reasons why similar studies differ considerably and to prepare a basis for fair techno-economic comparisons. Another objective has been to identify possible lack of industrial integration studies that may be of interest to carry out in a second phase of the project. Around 40 national and international reports and articles have been analysed and reviewed. The majority of the studies concern gasifiers installed in chemical pulp and paper mills where black liquor gasification is the dominating technology. District heating systems are also well represented. Only a few studies have been found with mechanical pulp and paper mills, steel industries and the oil refineries as case basis. Other industries have rarely, or not at all, been considered for industrial integration studies. Surprisingly, no studies regarding integration of biomass gasification neither in saw mills nor in wood pellet production industry have been found. In the published economic evaluations, it has been found that there is a large number of studies containing both integration and

  18. Thermal valorization of post-consumer film waste in a bubbling bed gasifier

    International Nuclear Information System (INIS)

    Highlights: • Film waste from packaging is a common waste, a fraction of which is not recyclable. • Gasification can make use of the high energy value of the non-recyclable fraction. • This waste and two reference polymers were gasified in a bubbling bed reactor. • This experimental research proves technical feasibility of the process. • It also analyzes impact of composition and ER on the performance of the plant. - Abstract: The use of plastic bags and film packaging is very frequent in manifold sectors and film waste is usually present in different sources of municipal and industrial wastes. A significant part of it is not suitable for mechanical recycling but could be safely transformed into a valuable gas by means of thermal valorization. In this research, the gasification of film wastes has been experimentally investigated through experiments in a fluidized bed reactor of two reference polymers, polyethylene and polypropylene, and actual post-consumer film waste. After a complete experimental characterization of the three materials, several gasification experiments have been performed to analyze the influence of the fuel and of equivalence ratio on gas production and composition, on tar generation and on efficiency. The experiments prove that film waste and analogue polymer derived wastes can be successfully gasified in a fluidized bed reactor, yielding a gas with a higher heating value in a range from 3.6 to 5.6 MJ/m3 and cold gas efficiencies up to 60%

  19. Gasification of empty fruit bunch for hydrogen rich fuel gas production

    Energy Technology Data Exchange (ETDEWEB)

    Mohammed, M.A.A.; Salmiaton, A.; Wan Azlina, W.A.K.G.; Mohamad Amran, M.S. [University Putra Malaysia, Selangor (Malaysia). Dept. of Chemical and Environmental Engineering

    2011-07-01

    Dependence on fossil fuels as the main energy source has led to serious energy crisis and environmental problems. Therefore, due to the environmental considerations as well as the increasing demand for energy in the world, more attention has been paid to develop new energy sources. There has been interest in the utilization of biomass for production of environmental friendly biofuels. Biomass is a CO{sub 2} neutral resource in the lifecycle while CO{sub 2} is a primary contributor to the global greenhouse effect. Hence, increasing attention is being paid to biomass as a substitute for fossil fuel to reduce the global greenhouse effect, particularly under the commitment of the Kyoto Protocol. Biomass used as an energy resource can be efficiently achieved by thermo-chemical conversion technology: pyrolysis, gasification or combustion. Gasification process is one of the most promising thermo-chemical conversion routes to recover energy from biomass. A study on gasification of Empty Fruit Bunch (EFB), a waste of the palm oil industry is investigated. The composition and particle size distribution of feedstock are determined and the thermal degradation behavior is analyzed by a thermogravimetric analysis (TGA). Then 300 g h{sup -1} fluidized bed bench scale gasification unit is used to investigate the effect of the operating parameters on biomass gasification namely reactor temperature in the range of 700--1000 C and feedstock particle size in the range of 0.3--1.0 mm. The main gas species generated, as identified by Gas Chromatography (GC), are H{sub 2} CO, CO{sub 2} and CH{sub 4}. With temperature increasing from 700 to 1000 C, the total gas yield is enhanced greatly and has reached the maximum value ({approx}92 wt. %, on the raw biomass sample basis) at 1000 C with big portions of H{sub 2} (38.02 vol.%) and CO (36.36 vol.%). Feedstock particle size shows some influence on the H{sub 2}, CO and CH{sub 4} yields. The feedstock particle size of 0.3 to 0.5 mm is found to

  20. Gasification of refuse-derived fuel in a high throughput gasification system

    International Nuclear Information System (INIS)

    Increasing quantities of municipal wastes have led to the development of numerous technologies for combustion or gasification of these wastes. Under sponsorship of the Department of Energy, Battelle has completed a preliminary investigation of gasification of prepared municipal wastes [refuse derived fuel (RDF)] to produce a medium Btu gas without oxygen in its High Throughput Gasification system. A successful test program was conducted in a 12 TPD Process Research Unit (PRU) to provide data on product gas composition and production rates possible with the RDF feedstock. Test data generated during the program were compared to an extensive data base generated with wood in the research unit. Results of this test program are presented along with data on waste water characteristics from the PRU. Data generated during the experimental program were used in the generation of a process conceptual design. A preliminary economic evaluation based on this design indicates that the Battelle process provides significant economic benefits when compared to mass burn technologies