WorldWideScience

Sample records for biomass cfb gasifier

  1. The Effect of Air Preheating in a Biomass CFB Gasifier using ASPEN Plus Simulation

    OpenAIRE

    Doherty, Wayne; Reynolds, Anthony; Kennedy, David

    2009-01-01

    In the context of climate change, increasing efficiency and energy security, biomass gasification is likely to play an important role in energy production. Atmospheric circulating fluidised bed (CFB) technology was selected for the current study. The primary objective of this research is to develop a computer simulation model of a CFB biomass gasifier that can accurately predict gasifier performance under various operating conditions. An original model was developed using ASPEN Plus (Advan...

  2. The effect of air preheating in a biomass CFB gasifier using ASPEN Plus simulation

    Energy Technology Data Exchange (ETDEWEB)

    Doherty, Wayne; Reynolds, Anthony; Kennedy, David [Department of Mechanical Engineering, Dublin Institute of Technology, Bolton Street, Dublin 1 (Ireland)

    2009-09-15

    In the context of climate change, efficiency and energy security, biomass gasification is likely to play an important role. Circulating fluidised bed (CFB) technology was selected for the current study. The objective of this research is to develop a computer model of a CFB biomass gasifier that can predict gasifier performance under various operating conditions. An original model was developed using ASPEN Plus. The model is based on Gibbs free energy minimisation. The restricted equilibrium method was used to calibrate it against experimental data. This was achieved by specifying the temperature approach for the gasification reactions. The model predicts syn-gas composition, conversion efficiency and heating values in good agreement with experimental data. Operating parameters were varied over a wide range. Parameters such as equivalence ratio (ER), temperature, air preheating, biomass moisture and steam injection were found to influence syn-gas composition, heating value, and conversion efficiency. The results indicate an ER and temperature range over which hydrogen (H{sub 2}) and carbon monoxide (CO) are maximised, which in turn ensures a high heating value and cold gas efficiency (CGE). Gas heating value was found to decrease with ER. Air preheating increases H{sub 2} and CO production, which increases gas heating value and CGE. Air preheating is more effective at low ERs. A critical air temperature exists after which additional preheating has little influence. Steam has better reactivity than fuel bound moisture. Increasing moisture degrades performance therefore the input fuel should be pre-dried. Steam injection should be employed if a H{sub 2} rich syn-gas is desired. (author)

  3. The effect of air preheating in a biomass CFB gasifier using ASPEN Plus simulation

    International Nuclear Information System (INIS)

    In the context of climate change, efficiency and energy security, biomass gasification is likely to play an important role. Circulating fluidised bed (CFB) technology was selected for the current study. The objective of this research is to develop a computer model of a CFB biomass gasifier that can predict gasifier performance under various operating conditions. An original model was developed using ASPEN Plus. The model is based on Gibbs free energy minimisation. The restricted equilibrium method was used to calibrate it against experimental data. This was achieved by specifying the temperature approach for the gasification reactions. The model predicts syn-gas composition, conversion efficiency and heating values in good agreement with experimental data. Operating parameters were varied over a wide range. Parameters such as equivalence ratio (ER), temperature, air preheating, biomass moisture and steam injection were found to influence syn-gas composition, heating value, and conversion efficiency. The results indicate an ER and temperature range over which hydrogen (H2) and carbon monoxide (CO) are maximised, which in turn ensures a high heating value and cold gas efficiency (CGE). Gas heating value was found to decrease with ER. Air preheating increases H2 and CO production, which increases gas heating value and CGE. Air preheating is more effective at low ERs. A critical air temperature exists after which additional preheating has little influence. Steam has better reactivity than fuel bound moisture. Increasing moisture degrades performance therefore the input fuel should be pre-dried. Steam injection should be employed if a H2 rich syn-gas is desired. (author)

  4. The Low temperature CFB gasifier

    DEFF Research Database (Denmark)

    Stoholm, P.; Nielsen, Rasmus Glar; Fock, Martin W.;

    2003-01-01

    %) particle separation by the hot secondary cyclone. The next LT-CFB experiment, currently under preparation, is expected to be on either municipal/industrial waste or animal manure. Eventually a 500 kW LT-CFB test plant scheduled for commission during summer 2003, and the anticipated primary LT...

  5. The Low Temperature CFB Gasifier

    DEFF Research Database (Denmark)

    Stoholm, P.; Nielsen, Rasmus Glar; Richardt, K.;

    2004-01-01

    straw, animal manure and waste and for co-firing the product gas in existing, e.g. coal fired power plant boilers. The aim is to prevent fouling, agglomeration and high temperature corrosion caused by potassium and chlorine and other fuel components when producing electricity. So far 92 hours......The Low Temperature Circulating Fluidised Bed (LT-CFB) gasification process is described together with the 50 kW and the 500 kW test plants and latest test results. The LT-CFB process is especially developed for medium and large scale (few to >100 MW) gasification of problematic bio-fuels like...... of experiments with the 50 kW test plant with two extremely difficult types of straw has shown low char losses and high retentions of ash including e.g. potassium. Latest 27 hours of experiments with dried, high ash pig- and hen manure has further indicated the concepts high fuel flexibility. The new 500 kW test...

  6. Biomass CFB gasifier connected to a 350 MW{sub t}h steam boiler fired with coal and natural gas - THERMIE demonstration project in Lahti in Finland

    Energy Technology Data Exchange (ETDEWEB)

    Palonen, J. [Foster Wheeler Energia Oy, Varkaus (Finland). Varkaus Global New Products

    1997-12-31

    The successful experience in developing the advanced Foster Wheeler Energi Oy`s (former Ahlstroem Pyropower) Circulating Fluidized Bed combustion system subsequently led to the development of the CFB gasification technology in the early 1980s. The driving force for the developing work was the dramatic increase in oil price during the oil crises. The primary advantage of CFB gasification technology is that the it enables the substitution of expensive fuels e.g. oil or gas with cheap solid fuels. These cheap fuels are typically different types of waste woods, bark or other biofuels. In the CFB gasifier these solid fuels are converted to gaseous fuel which can be used instead of other expensive fuels. In some cases this also solves a waste disposal problem, providing a secondary economic and environmental benefit. Foster Wheeler Energia Oy has supplied four commercial scale atmospheric CFB gasifiers in the mid 80s to the pulp and paper industry with capacities from 17 to 35 MW based on fuel input. These applications utilize waste wood as feedstock and the units are still successfully operation today. Lahden Laempoevoima Oy is a Finnish power company producing power and district heat for the city of Lahti. The company is 50 % owned by the city of Lahti and 50 % by Imatran Voima Oy, which is the largest utility power company in Finland. Lahden Laempoevoima Oy operates the Kymijaervi power plant locating nearby the city of Lahti in Southern Finland. To keep the energy prices as low as possible, Lahden Laempoevoima is continuously looking for the most economical fuel sources, and simultaneously, trying to improve the environmental acceptability of the energy production. At the moment, about 300 GWh/a different type of biofuels and refuse fuels are available in the Lahti area. On an annual basis, the available amount of biofuels and refuse fuels is enough to substitute for about 15 % of the fuels burned in the main boiler equalling max 30 % of coal. The aim in this Lahden

  7. Biomass gasification as the first hot step in clean syngas production process - gas quality optimization and primary tar reduction measures in a 100 kW thermal input steam-oxygen blown CFB gasifier

    International Nuclear Information System (INIS)

    g m-3 (STP). Moreover, magnesite complied with the expectation to have a positive impact on agglomeration prevention for the agricultural fuels containing alkali and chlorine in the ash. The kind of olivine applied during the experiments did not yield the expected tar reduction; the measured tar concentration was even higher than when quartz sand was used as bed material. Finally kaolin proved to be an effective additive to counteract the agglomeration when fuels with high alkali content in the ash are gasified using bed material that is rich in silica, as it is the case with quartz sand and olivine. -- Highlights: → Gasification of woody and agricultural biomass was extensively tested in a steam-oxygen blown CFB gasifier. → Stable operation was possible, even with agricultural fuels, provided the agglomeration is counteracted using kaolin. → Operation with straw caused downstream problems due to KCl deposition. → Combination of magnesite as bed material and miscanthus as fuel yielded highest hydrogen fraction and lowest amount of tar. → The kind of olivine used in the experiments did not cause the expected reduction of the tar yield.

  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. 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....

  10. Handbook of biomass downdraft gasifier engine systems

    Energy Technology Data Exchange (ETDEWEB)

    Reed, T B; Das, A

    1988-03-01

    This handbook has been prepared by the Solar Energy Research Institute under the US Department of Energy /bold Solar Technical Information Program/. It is intended as a guide to the design, testing, operation, and manufacture of small-scale (less than 200 kW (270 hp)) gasifiers. A great deal of the information will be useful for all levels of biomass gasification. The handbook is meant to be a practical guide to gasifier systems, and a minimum amount of space is devoted to questions of more theoretical interest.

  11. THE LT-CFB GASIFIER – FIRST TEST RESULTS FROM THE 500 KW TEST PLANT

    DEFF Research Database (Denmark)

    Nielsen, Rasmus Glar; Stoholm, Peder; Nielsen, Mads Brix;

    2005-01-01

    The Low Temperature Circulating Fluidised Bed (LT-CFB) gasification process is briefly described together with the first test results from the new 500 kW test plant. The process aims primarily at co-firing low grade biomass and waste products at power plants and offer several advantages to direct...... in solid state, and can be separated from the gas using only a simple hot cyclone. Mass- and energy balances show that the conversion efficiency from fuel heating value to energy content in the product gas is more than 90% and even higher efficiencies are anticipated in upscaled plants....

  12. Two-dimensional biomass combustion modeling of CFB

    Energy Technology Data Exchange (ETDEWEB)

    Afsin Gungor [Nigde University, Nigde (Turkey). Department of Mechanical Engineering, Faculty of Engineering and Architecture

    2008-07-15

    In this study, a 2D model for a CFB biomass combustor has been developed which integrates and simultaneously predicts the hydrodynamics, heat transfer and combustion aspects. Combustor hydrodynamic is modeled taking into account previous work. Simulation model calculates the axial and radial distribution of voidage, velocity, particle size distribution, pressure drop, gas emissions and temperature at each time interval for gas and solid phase both for bottom and upper zones. The model results are compared with and validated against experimental data both for small-size and industrial-size biomass combustors which uses different types of biomass fuels given in the literature. As a result of sensitivity analysis, it is observed that: major portion of the combustion will take place in the upper zone, the air staging could improve combustion, for industrial-size CFB biomass combustors and the decrease of NOx adversely results in high CO emissions as air ratio decreases. Unexpected results concerning the emissions is caused by using data of different sized CFBs and is clearly an indicator of the necessity to compare the model results with various sized CFBs as far as possible. 71 refs., 10 figs., 5 tabs.

  13. Simulation of the biomass updraft gasifier

    Energy Technology Data Exchange (ETDEWEB)

    Teislev, B.

    2006-07-15

    A consistent (steady state, one-dimensional) mathematical model for a biomass updraft gasifier has been developed based on mass- and energy balances and assuming ideal mixtures of gases and solids. The gases considered are 0{sub 2}, N{sub 2}, H{sub 2}O, CO{sub 2}, H{sub 2}, CO, CH{sub 4} and TAR and the solids are Ash, Carbon, dry Wood and HzO moisture and described by their partial densities in the gasifier bed, together with their axial velocities and temperature. The processes considered are Carbon Oxidation, H{sub 2}0 and CO{sub 2} reduction, the Water Gas Shift process, dry Wood Pyrolysis and Moist Biomass Drying and are described by their temperature and concentration dependant reaction rates. The same mathematical formulation is used throughout the reactor and the methodology used is to solve the resulting 16 partial and algebraic equations (with 16 variables, 8 gaseous partial densities, 4 solids partial densities, 2 velocities and 2 temperatures) in a Newton-Raphson approach using variable length of the integration step. The transition through oxidation and reduction and the passage through the drying zone has been preliminary verified to be in accordance with experimental evidence, but the software developed has not yet been able to describe the transition to pyrolysis and drying and therefore, the final product gas composition from the updraft gasifier has not been verified (apart from verification using a zero-dimensional model). For use in further work an Addendum describing the approach in the form of a 'pseudo code' (including several comments for readers not conversant with the programming language used in the present work - Visual Basic) is included. (au)

  14. Simulation of the biomass updraft gasifier

    Energy Technology Data Exchange (ETDEWEB)

    Teislev, B.

    2006-07-15

    A consistent (steady state, one-dimensional) mathematical model for a biomass updraft gasifier has been developed based on mass- and energy balances and assuming ideal mixtures of gases and solids. The gases considered are 0{sub 2}, N{sub 2}, H{sub 2}0, CO{sub 2}, H{sub 2}, CO, CH{sub 4} and TAR and the solids are Ash, Carbon, dry Wood and H{sub 2}O moisture and described by their partial densities in the gasifier bed - together with their axial velocities and temperature. The processes considered are Carbon Oxidation, H{sub 2}0 and CO{sub 2} reduction, the Water Gas Shift process, dry Wood Pyrolysis and Moist Biomass Drying and are described by their temperature and concentration dependant reaction rates. The same mathematical formulation is used throughout the reactor and the methodology used is to solve the resulting 16 partial and algebraic equations (with 16 variables - 8 gaseous partial densities, 4 solids partial densities, 2 velocities and 2 temperatures) in a Newton-Raphson approach using variable length of the integration step. The transition through oxidation and reduction and the passage through the drying zone has been preliminary verified to be in accordance with experimental evidence, but the software developed has not yet been able to describe the transition to pyrolysis and drying and therefore, the final product gas composition from the updraft gasifier has not been verified (apart from verification using a zero-dimensional model). For use in further work an Addendum describing the approach in the form of a 'pseudo code' (including several comments for readers not conversant with the programming language used in the present work - Visual Basic) is included. (au)

  15. Biomass Gasifier for Computer Simulation; Biomassa foergasare foer Computer Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Hansson, Jens; Leveau, Andreas; Hulteberg, Christian [Nordlight AB, Limhamn (Sweden)

    2011-08-15

    This report is an effort to summarize the existing data on biomass gasifiers as the authors have taken part in various projects aiming at computer simulations of systems that include biomass gasification. Reliable input data is paramount for any computer simulation, but so far there is no easy-accessible biomass gasifier database available for this purpose. This study aims at benchmarking current and past gasifier systems in order to create a comprehensive database for computer simulation purposes. The result of the investigation is presented in a Microsoft Excel sheet, so that the user easily can implement the data in their specific model. In addition to provide simulation data, the technology is described briefly for every studied gasifier system. The primary pieces of information that are sought for are temperatures, pressures, stream compositions and energy consumption. At present the resulting database contains 17 gasifiers, with one or more gasifier within the different gasification technology types normally discussed in this context: 1. Fixed bed 2. Fluidised bed 3. Entrained flow. It also contains gasifiers in the range from 100 kW to 120 MW, with several gasifiers in between these two values. Finally, there are gasifiers representing both direct and indirect heating. This allows for a more qualified and better available choice of starting data sets for simulations. In addition to this, with multiple data sets available for several of the operating modes, sensitivity analysis of various inputs will improve simulations performed. However, there have been fewer answers to the survey than expected/hoped for, which could have improved the database further. However, the use of online sources and other public information has to some extent counterbalanced the low response frequency of the survey. In addition to that, the database is preferred to be a living document, continuously updated with new gasifiers and improved information on existing gasifiers.

  16. Scaling up biomass gasifier use: an application-specific approach

    International Nuclear Information System (INIS)

    Biomass energy accounts for about 11% of the global primary energy supply, and it is estimated that about 2 billion people worldwide depend on biomass for their energy needs. Yet, most of the use of biomass is in a primitive and inefficient manner, primarily in developing countries, leading to a host of adverse implications on human health, environment, workplace conditions, and social well being. Therefore, the utilization of biomass in a clean and efficient manner to deliver modern energy services to the world's poor remains an imperative for the development community. One possible approach to do this is through the use of biomass gasifiers. Although significant efforts have been directed towards developing and deploying biomass gasifiers in many countries, scaling up their dissemination remains an elusive goal. Based on an examination of biomass gasifier development, demonstration, and deployment efforts in India-a country with more than two decades of experiences in biomass gasifier development and dissemination, this article identifies a number of barriers that have hindered widespread deployment of biomass gasifier-based energy systems. It also suggests a possible approach for moving forward, which involves a focus on specific application areas that satisfy a set of criteria that are critical to deployment of biomass gasifiers, and then tailoring the scaling up strategy to the characteristics of the user groups for that application. Our technical, financial, economic and institutional analysis suggests an initial focus on four categories of applications-small and medium enterprises, the informal sector, biomass-processing industries, and some rural areas-may be particularly feasible and fruitful

  17. LT-CFB. Applications and follow-up. CP Kelco. Appendix 1. [Low Temperature Circulating Fluid Bed gasifier]; LT-CFB. Anvendelsesmuligheder og opfoelgning. CP Kelco. Bilag 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-04-15

    This appendix describes how LT-CFB advantageously can gasify residual products at the company CP Kelco's factory. CP Kelco produces the gelation, thickeners and stabilizers carrageenan and pectin from seaweed and citrus peel. Residues from the production consist of a fiber-containing biological material, which has a calorific value of dry matter about 15 to 20 MJ / kg. In addition, there are waste products from the wastewater treatment plant, which are also proposed re-used in the project. The report describes the economic analyses, the overall data and system design for two scenarios, whereas the description of the plant capacities, sizes and detailed data etc. are described only for one scenario. In addition to savings in the purchase of natural gas the gas production also results in a significant reduction in CO{sub 2} emissions, the product gas being characterized as CO{sub 2} neutral. Since CP Kelco is subject to the CO{sub 2} quota system the saved amount of CO{sub 2} emissions represents a significant value. In the economic analyses, the value of 1 ton of CO{sub 2} is set at DKK 100. (LN)

  18. Engineering analysis of biomass gasifier product gas cleaning technology

    Energy Technology Data Exchange (ETDEWEB)

    Baker, E.G.; Brown, M.D.; Moore, R.H.; Mudge, L.K.; Elliott, D.C.

    1986-08-01

    For biomass gasification to make a significant contribution to the energy picture in the next decade, emphasis must be placed on the generation of clean, pollutant-free gas products. This reports attempts to quantify levels of particulated, tars, oils, and various other pollutants generated by biomass gasifiers of all types. End uses for biomass gases and appropriate gas cleaning technologies are examined. Complete systems analysis is used to predit the performance of various gasifier/gas cleanup/end use combinations. Further research needs are identified. 128 refs., 20 figs., 19 tabs.

  19. Comparison of pulp-mill-integrated hydrogen production from gasified black liquor with stand-alone production from gasified biomass

    International Nuclear Information System (INIS)

    When gasified black liquor is used for hydrogen production, significant amounts of biomass must be imported. This paper compares two alternative options for producing hydrogen from biomass: (A) pulp-mill-integrated hydrogen production from gasified back liquor; and (B) stand-alone production of hydrogen from gasified biomass. The comparison assumes that the same amount of biomass that is imported in Alternative A is supplied to a stand-alone hydrogen production plant and that the gasified black liquor in Alternative B is used in a black liquor gasification combined cycle (BLGCC) CHP unit. The comparison is based upon equal amounts of black liquor fed to the gasifier, and identical steam and power requirements for the pulp mill. The two systems are compared on the basis of total CO2 emission consequences, based upon different assumptions for the reference energy system that reflect different societal CO2 emissions reduction target levels. Ambitions targets are expected to lead to a more CO2-lean reference energy system, in which case hydrogen production from gasified black liquor (Alternative A) is best from a CO2 emissions' perspective, whereas with high CO2 emissions associated with electricity production, hydrogen from gasified biomass and electricity from gasified black liquor (Alternative B) is preferable. (author)

  20. Biomass-Derived Hydrogen from a Thermally Ballasted Gasifier

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Robert C

    2007-04-06

    The goal of this project is to develop an indirectly heated gasification system that converts switchgrass into hydrogen-rich gas suitable for powering fuel cells. The project includes investigations of the indirectly-heated gasifier, development of particulate removal equipment, evaluation of catalytic methods for upgrading producer gas, development of contaminant measurement and control techniques, modeling of the thermal performance of the ballasted gasifier, and estimation of the cost of hydrogen from the proposed gasification system. Specific technologies investigated include a thermally ballasted gasifier, a moving bed granular filter, and catalytic reactors for steam reforming and water-gas shift reaction. The approach to this project was to employ a pilot-scale (5 ton per day) gasifier to evaluate the thermally ballasted gasifier as a means for producing hydrogen from switchgrass. A slipstream from the gasifier was used to evaluate gas cleaning and upgrading options. Other tests were conducted with laboratory-scale equipment using simulated producer gas. The ballasted gasifier operated in conjunction with a steam reformer and two-stage water-gas shift reactor produced gas streams containing 54.5 vol-% H2. If purge gas to the feeder system could be substantially eliminated, hydrogen concentration would reach 61 vol-%, which closely approaches the theoretical maximum of 66 vol-%. Tests with a combined catalyst/sorbent system demonstrated that steam reforming and water-gas shift reaction could be substantially performed in a single reactor and achieve hydrogen concentrations exceeding 90 vol-%. Cold flow trials with a laboratory-scale moving bed granular filter achieved particle removal efficiencies exceeding 99%. Two metal-based sorbents were tested for their ability to remove H2S from biomass-derived producer gas. The ZnO sorbent, tested at 450° C, was effective in reducing H2S from 200 ppm to less than 2 ppm (>99% reduction) while tests with the MnO sorbent

  1. 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

  2. Study tour to biomass gasifiers in Germany

    International Nuclear Information System (INIS)

    A study trip to a biomass gasification plant in Germany took place from 13-15 November 2000. The goal of the trip was to obtain information on German developments, experience, and possibilities in the field of biomass gasification. The participants were representatives of Dutch parties in the energy sector: waste sector, manufacturers, producers, policy makers and consultants. The most important feature was the visit to plants that were in operation. Due in particular to the new EEG (Emeuerbare-Energien-Gesetz/Renewable Energy) legislation, German policy makers have created an initial market for sustainable energy with a degree of success. The key feature is that EEG makes projects 'bankable' by guaranteeing a return delivery compensation. An EEG-type scheme designed to accelerate the development of sustainable energy could be an interesting instrument also for the Netherlands. The plan was to visit four plants and have a number of presentations in a period of three days. Preference was for relatively new plants with differing concepts. The following plants were visited and/or presented: 200-kWe CHP wood gasification plant, based on AHT technology, located at Domsland in Eckenfoerde; a 10,000 tonnes/year wood gasification plant, based on 'cupola furnace' technology of blast furnaces, located at Holzhausen near Leipzig; a 1-MWe wood gasification plant, based on Carbo-V technology, located at Freiberg; and finally a 23-MWe CBP wood gasification plant, also based on Juch technology, located at Siebenlehn. In clearly appears that Germany is ahead of the Netherlands in the realisation of gasification plants. Still, there are certain problems with the reliability of operation. The plants selected were relatively new (with the possible exception of Espenhain) and they are having too many teething problems. Sound insight has been obtained into the various concepts of decentralised energy generation from biomass and how this can be fitted into the existing infrastructure

  3. Investigation of operational parameters for an industrial CFB combustor of coal, biomass and sludge

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The combustion of coal and/or biomass (sludge, wood waste, RDF, etc.) in a circulating fluidized bed has been a commercial topper for over 20 years, and references to principles and applications are numerous and widespread although few data are presented concerning the operation of large scale CFB-units. The authors studied the CFB-combustion at UPM-Kymmene (Ayr), a major paper mill relying for its steam production upon the combustion of coal (80-85%), wood bark (5-10%) and wastewater treatment sludge (5-10%). The maximum capacity of the CFB is 58 MWth.A complete diagnostic of the operation was made, and additional tests were performed to assess the operating mode. The plant schematics,relevant dimensions and process data are given. To assess the operation of the UPM-CFB, it is important to review essential design parameters and principles of CFB combustors, which will be discussed in detail to include required data, heat balance and flowrates, operating versus transport velocity, kinetics and conversion (including the possible effect of the Bouduard reaction if carbon is present).Since the residence time in the riser and the cyclone efficiency determine the burnout of circulating fuel-particles, the UPM-CFB was subjected to a stimulus response technique using nickel oxide as tracer. Results illustrate the efficiency of the cyclone separation and the number of recycle loops for particles of a given size. Results will also be used to assess the cyclone operation and efficiency and to comment upon expected and measured carbon conversion.

  4. Characterization and treatment of tars and biomass gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Baker, E.G.; Brown, M.D.; Elliott, D.C.; Mudge, L.K.

    1988-08-01

    Biomass gasification and pyrolysis have the potential to make a significant impact on energy supplies in the United States and have demonstrated their commercial potential in many projects around the country. The environmental aspects of biomass gasification need to be defined to assure that the technology makes its maximum impact on energy supplies. One area that needs further development is characterization and treatment of the tar byproduct from gasifiers and pyrolyzers. This paper examines the effect of the type of gasifier/pyrolyzer and the processing conditions on the yield and properties of tars and condensates. End use limitations for tars are discussed. Wet scrubbing is the most common method of tar removal from gases. The scrub liquor will require treatment to remove organics before it can be disposed. Pacific Northwest Laboratory (PNL) is developing a catalytic tar destruction process that will treat the hot, raw gas from the gasifier and convert the tars to gas. The process increases the gas yield and cold gas efficiency of the gasification process, produces a clean gas that can be used for many applications, and produces a clean condensate that can be disposed with minimal treatment. 10 refs., 2 figs., 1 tab.

  5. Sampling of contaminants from product gases of biomass gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Staahlberg, P.; Lappi, M.; Kurkela, E.; Simell, P.; Oesch, P.; Nieminen, M. [VTT Energy, Espoo (Finland). New Energy Technologies

    1998-12-01

    Reliable sampling and analysis of products from biomass gasification are essential for the successful process development and economical operation of commercial gasifiers. One of the most important and most difficult analytical tasks is to characterise the emissions from the gasifiers. This report presents a review of the sampling and analytical systems employed and developed when doing research on coal and biomass gasification. In addition to the sampling systems published in the literature, experiences obtained in various biomass gasification R and D projects of VTT in 1985-1995 are described. The present sampling methods used for different gas contaminants at VTT are also briefly presented. This report focuses mainly on the measurement of tars, nitrogen compounds and sulphur gases. Isokinetic and non-isokinetic sampling train systems are described and, in addition, special sampling apparatus based on liquid-quenched probe and gas dilution is briefly outlined. Sampling of tars with impinger systems and sampling of heavy tars with filter techniques are described in detail. Separate sampling of particulates is briefly discussed. From inorganic compounds the sampling systems used for H{sub 2}S and other sulphur gases, NH{sub 3} and HCN and HCl are presented. Proper storage of the samples is also included in the report. (orig.) 90 refs.

  6. Advanced biomass power generation: The biomass-integrated gasifier/gas turbine and beyond

    International Nuclear Information System (INIS)

    The most promising initial strategy for modernizing bioenergy is the production of electricity or the cogeneration of electricity and heat using advanced gas turbines fired by gasified biomass. The major advances that have been made in coal gasification technology, to marry the gas turbine to coal, are readily adaptable to biomass applications. integrating biomass gasifiers with aeroderivative gas turbines in particular makes it possible to achieve high efficiencies and low unit capital costs at the modest scales required with bioenergy systems. Beyond the turn of the century fuel cells operated on gasified biomass offer the promise of even higher performance levels. For the near term, electricity produced with biomass-integrated gasifier/gas turbine (BIG/GT) power systems not only offers major environmental benefits but also would be competitive with electricity produced from fossil fuels and nuclear energy in a wide range of circumstances. It is reasonable to expect that biomass could be providing 25-35% of total global power generation in the second quarter of the next century, helping make it possible to substantially reduce CO2 emissions from the power sector relative to present levels in that time frame

  7. 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

  8. LT-CFB. Further development and commercialization. Final report. [Low Temperature Circulating Fluid Bed gasifier]; LT-CFB. Videreudvikling og kommercialisering. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    Stoholm, P. [DFBT, Roskilde (Denmark); Birk Henriksen, U.; Ahrentfeldt, J. [Technical Univ. of Denmark. DTU Chemical Engineering, CHEC Research Centre, Roskilde (Denmark); Cramer, J.; Dietrich, J.; Christiansen, Knud [FORCE Technology, Kgs. Lyngby (Denmark); Krogh, J. [Anhydro A/S, Soeborg (Denmark)

    2011-12-15

    The starting point for the project was the good results achieved in a previous project, in which a series of experiments were carried out with a 500 kW pilot plant at teh Technical University of Denmark. The main task was then to find a way forward towards further scale-up, demonstration and commercialization. The project's partners chose to study three possible sites for demonstration. However, during the project both framework conditions as well as DONG Energy's strategy changed, which resulted in the company taking over the LT-CFB technology in December 2009. As a first step a 6 MW demonstration plant will now be set up at the Asnaes power plant expected to start in spring 2011. The project has also been buit a new mobile 100 kW LT-CFB plant for the further optimization of the process and for short-term trials of new fuels. At the new plant a number of successful trials were performed with straw and residual fibers. Furthermore, it is experimentally demonstrated that it is possible to cool the tar-containing gas to approx. 300 degrees C and purify the gas in a bag filter, so it can be used in natural gas-fired power plant boilers. With the new mobile system, it will now be easier to perform experiments with a number of new fuels such as unsorted municipal waste, bone meal and dried sewage sludge. (LN)

  9. Experimental Gasification of Biomass in an Updraft Gasifier with External Recirculation of Pyrolysis Gases

    OpenAIRE

    Adi Surjosatyo; Fajri Vidian; Yulianto Sulistyo Nugroho

    2014-01-01

    The updraft gasifier is a simple type of reactor for the gasification of biomass that is easy to operate and has high conversion efficiency, although it produces high levels of tar. This study attempts to observe the performance of a modified updraft gasifier. A modified updraft gasifier that recirculates the pyrolysis gases from drying zone back to the combustion zone and gas outlet at reduction zone was used. In this study, the level of pyrolysis gases that returned to the combustion zone w...

  10. Pyrolysis Model of Single Biomass Pellet in Downdraft Gasifier

    Institute of Scientific and Technical Information of China (English)

    薛爱军; 潘继红; 田茂诚; 伊晓璐

    2016-01-01

    By coupling the heat transfer equation with semi-global chemical reaction kinetic equations, a one-dimensional, unsteady mathematical model is developed to describe the pyrolysis of single biomass pellet in the pyrolysis zone of downdraft gasifier. The simulation results in inert atmosphere and pyrolysis zone agree well with the published experimental results. The pyrolysis of biomass pellets in pyrolysis zone is investigated, and the results show that the estimated convective heat transfer coefficient and emissivity coefficient are suitable. The mean pyro-lysis time is 15.22%, shorter than that in inert atmosphere, and the pellet pyrolysis process in pyrolysis zone belongs to fast pyrolysis. Among the pyrolysis products, tar yield is the most, gas the second, and char the least. During pyrolysis, the temperature change near the center is contrary to that near the surface. Pyrolysis gradually moves inwards layer by layer. With the increase of pyrolysis temperature and pellet diameter, the total pyrolysis time, tar yield, char yield and gas yield change in different ways. The height of pyrolysis zone is calculated to be 1.51—3.51 times of the characteristic pellet diameter.

  11. REFINEMENT OF PRODUCER GAS GENERATED FROM BIOMASS GASIFIER

    Directory of Open Access Journals (Sweden)

    L. KUMARARAJA

    2016-01-01

    Full Text Available Producer gas (PG generated from biomass by thermo-chemical gasification process has been proved to be a reliable and renewable substitute for petroleum fuels to drive internal combustion engines. The gasification technology has been developed well and also commercialised. However, more technological advancements must happen in the refining of PG. Generally, the refinement is confined to the removal of tar and particulates from PG before supplying it to the engines. This paper proposes to remove additionally carbon dioxide and water vapour from PG so that its heating value can be increased and faster combustion can be attained in the engine cylinder. In this direction, the various CO2 removal technologies which are currently employed for combustion flue gas, natural gas and biogas have been first studied in detail. They are: physical absorption in solvents, chemical absorption by reagents, adsorption, membrane separation and refrigeration. In the present research, a batch of experiments has been conducted by washing PG with water to absorb CO2 physically and in a separate batch of experiments PG has been treated with aqueous ammonia to absorb CO2 chemically. For both experiments, the PG was generated by a downdraft biomass gasifier fed with wood pieces. The CO2 reduction obtained was 10.9% in physical absorption by water and 95% in chemical absorption by aqueous ammonia. Along with the reduction of CO2 and H2O from PG, the tar and particulates content of PG could also be reduced by absorption method.

  12. Cogeneration based on gasified biomass - a comparison of concepts

    Energy Technology Data Exchange (ETDEWEB)

    Olsson, Fredrik

    1999-01-01

    In this report, integration of drying and gasification of biomass into cogeneration power plants, comprising gas turbines, is investigated. The thermodynamic cycles considered are the combined cycle and the humid air turbine cycle. These are combined with either pressurised or near atmospheric gasification, and steam or exhaust gas dryer, in a number of combinations. An effort is made to facilitate a comparison of the different concepts by using, and presenting, similar assumptions and input data for all studied systems. The resulting systems are modelled using the software package ASPEN PLUS{sup TM}, and for each system both the electrical efficiency and the fuel utilisation are calculated. The investigation of integrated gasification combined cycles (IGCC), reveals that systems with pressurised gasification have a potential for electrical efficiencies approaching 45% (LHV). That is 4 - 5 percentage points higher than the corresponding systems with near atmospheric gasification. The type of dryer in the system mainly influences the fuel utilisation, with an advantage of approximately 8 percentage points (LHV) for the steam dryer. The resulting values of fuel utilisation for the IGCC systems are in the range of 78 - 94% (LHV). The results for the integrated gasification humid air turbine systems (IGHAT) indicate that electrical efficiencies close to the IGCC are achievable, provided combustion of the fuel gas in highly humidified air is feasible. Reaching a high fuel utilisation is more difficult for this concept, unless the temperature levels in the district heating network are low. For comparison a conventional cogeneration plant, based on a CFB boiler and a steam turbine (Rankine cycle), is also modelled in ASPEN PLUS{sup TM}. The IGCC and IGHAT show electrical efficiencies in the range of 37 - 45% (LHV), compared with a calculated value of 31% (LHV) for the Rankine cycle cogeneration plant. Apart from the electrical efficiency, also a high value of fuel

  13. Biomass Power Generation through Direct Integration of Updraft Gasifier and Stirling Engine Combustion System

    OpenAIRE

    Jai-Houng Leu

    2010-01-01

    Biomass is the largest renewable energy source in the world. Its importance grows gradually in the future energy market. Since most biomass sources are low in energy density and are widespread in space, small-scale biomass conversion system is therefore more competitive than a large stand-alone conversion plant. The current study proposes a small-scale solid biomass power system to explore the viability of direct coupling of an updraft fixed bed gasifier with a Stirling engine. The modified u...

  14. A downdraft high temperature steam-only solar gasifier of biomass char: A modelling study

    International Nuclear Information System (INIS)

    A numerical model of a solar downdraft gasifier of biomass char (biochar) with steam based on the systems kinetics is developed. The model calculates the dynamic and steady state profiles, predicting the temperature and concentration profiles of gas and solid phases, based on the mass and heat balances. The Rosseland equation is used to calculate the radiative transfer within the bed. The char reactivity factor (CFR) is taken into account with an exponential variation. The bed heating dynamics as well as the steam velocity effects are tested. The model results are compared with different experimental results from a solar packed bed gasifier, and the temperature profile is compared to an experimental downdraft gasifier. Hydrogen is the principal product followed by carbon monoxide, the carbon dioxide production is small and the methane production is negligible, indicating a high quality syngas production. By applying the temperature gradient theory in the steam-only gasification process for a solar gasifier design, a solar downdraft gasifier improves the energy conversion efficiency by over 20% when compared to a solar packed bed gasifier. The model predictions are in good agreement with the experimental results found in the literature. -- Highlights: → The solar downdraft gasifier set-up improve the solar updraft gasifier performance. → The temperature gradient theory is introduced. → A high quality syngas produced, the hydrogen is the principal component. → An exponential CFR variation is adjusted to the heat transfer in the bed.

  15. PERFORMANCE STUDIES ON DOWNDRAFT GASIFIER WITH BIOMASS ENERGY SOURCES AVAILABLE IN REMOTE VILLAGES

    Directory of Open Access Journals (Sweden)

    V. ChristusJeya Singh

    2014-01-01

    Full Text Available Increasing global concern over the environmental issues and depletion of fossil fuels, significant interest has been shown by the researchers to develop alternate energy technologies like biomass, biogas, solar to meet the future energy demand. The prediction of the performance of different biomass energy sources in gasifiers is needed for the implementation of this technology to fulfil the need of decentralized heat and power applications, relevant to remote villages. This study presents the theoretical and experimental studies conducted on a 50 kW downdraft biomass gasifier with various biomass materials such as wood, coconut shell, rubber seed kernel and coir pith which are generally available in villages. Two-zone kinetic equilibrium model approach is used to predict the composition and temperature of the producer gas. The influence of equivalence ratio on the reaction temperature, quality of producer gas and gasifier conversion efficiency are discussed. The experimental and theoretical studies show that the rubber seed kernel can be effectively used as a feedstock of the biomass gasifier to meet the rural energy demand.

  16. Model Research of Gas Emissions From Lignite and Biomass Co-Combustion in a Large Scale CFB Boiler

    Directory of Open Access Journals (Sweden)

    Krzywański Jarosław

    2014-06-01

    Full Text Available The paper is focused on the idea of a combustion modelling of a large-scale circulating fluidised bed boiler (CFB during coal and biomass co-combustion. Numerical computation results for three solid biomass fuels co-combustion with lignite are presented in the paper. The results of the calculation showed that in previously established kinetics equations for coal combustion, some reactions had to be modified as the combustion conditions changed with the fuel blend composition. Obtained CO2, CO, SO2 and NOx emissions are located in borders of ± 20% in the relationship to the experimental data. Experimental data was obtained for forest biomass, sunflower husk, willow and lignite cocombustion tests carried out on the atmospheric 261 MWe COMPACT CFB boiler operated in PGE Turow Power Station in Poland. The energy fraction of biomass in fuel blend was: 7%wt, 10%wt and 15%wt. The measured emissions of CO, SO2 and NOx (i.e. NO + NO2 were also shown in the paper. For all types of biomass added to the fuel blends the emission of the gaseous pollutants was lower than that for coal combustion.

  17. DEVELOPMENT AND EVALUATION OF A LOW-DENSITY BIOMASS FEEDING SYSTEM FOR FLUIDIZED BED GASIFIERS

    OpenAIRE

    A. E. Ghaly; A. Ergudenler; S. Alsuhaibani; V. V. Ramakrishnan

    2013-01-01

    For efficient operation of a biomass gasifier, the biomass material must be fed continuously to the system. A feeding system for chopped straw and rice husk was designed, constructed and evaluated. It consisted of: a frame, a hopper, an auger, two agitators, a drive system and a power unit. Initial testing showed that wheat straw and rice husk, being highly cohesive materials, created tunnel flow and piping conditions. This occurs when the pressure above an impending dome of material is too s...

  18. Waste heat recovery using a thermoelectric power generation system in a biomass gasifier

    International Nuclear Information System (INIS)

    The aim of this study is to investigate the use of waste heat that is recovered from a biomass gasifier. In the gasification process, the low heating value of biomass can be transferred to a high heating value for combustible gaseous fuel, a form that is widely used in industry and power plants. Conventionally, some of cleaning processes need to be conducted under higher operating temperatures that the low temperatures typically used to burn biomass. Therefore, the catalytic reactor was designed before installation the scrubber in the downdraft gasifier system to make effective use of the waste heat. The experimental result shows that the temperature of the gasifier outlet is about 623–773 K; dolomite is used for tar removal in the catalytic reactor. To further improve the use of waste heat, a thermoelectric generator is added to provide for the recovery of waste heat. The thermoelectric generator system is manufactured using a Bi2Te3 based material and is composed of eight thermoelectric modules on the surface of catalytic reactor. The measured surface temperature of the catalytic reactor is 473–633 K that is the correct temperature for Bi2Te3 as thermoelectric generator. The result shows that the maximum power output of the thermoelectric generator system is 6.1 W and thermoelectric generator power density is approximately 193.1 W/m2. - Highlights: • Set up the thermoelectric power generation system to recover waste heat from biomass gasifier. • Bi2Te3 based material is suitable for choosing as a thermoelectric generator in the waste heat recovery temperature range of 473–633 K form gasifier. • The maximum power density can reach 193.1 W/m2 for waste heat recovery

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

    Directory of Open Access Journals (Sweden)

    Luis Correas

    2004-12-01

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

  20. Numerical Study on Combustion Features of Gasified Biomass Gas

    OpenAIRE

    Zhang, Xiaoxiang

    2015-01-01

    There is a great interest to develop biomass combustion systems for industrial and utility applications. Improved biomass energy conversion systems are designed to provide better combustion efficiencies and environmental friendly conditions, as well as the fuel flexibility options in various applications. The gas derived from the gasification process of biomass is considered as one of the potential candidates to substitute traditional fuels in a combustion process. However, the gascomposition...

  1. 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.

  2. Performance modelling and validation of biomass gasifiers for trigeneration plants

    OpenAIRE

    Puig Arnavat, Maria

    2011-01-01

    This thesis develops a simple but rigorous model for simulation, design and preliminary evaluation of trigeneration plants based on biomass gasification. It includes a review and study of various models proposed for the biomass gasification process and different plant configurations. A modified thermodynamic equilibrium model is developed for application to real processes that do not reach equilibrium. In addition, two artificial neural network models, based on experimental published data, ar...

  3. 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

  4. Decomposition of matters and biomass gasifying in plasma generated in plasmatron stabilised by water

    International Nuclear Information System (INIS)

    In this paper experimental results of Decomposition of matters and biomass gasifying in plasma generated in plasmatron stabilised by water are presented. Used plasmatron is described. Process is characterised by high efficiency. Synthetic gas produced with this technology has high quality and is suitable for next technological treatment, it has high content of hydrogen and carbon monooxide, a little content of carbon dioxide and other gases

  5. 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.

  6. 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....

  7. Three-dimensional full-loop simulation of a dual fluidized-bed biomass gasifier

    OpenAIRE

    Liu, H; Cattolica, RJ; Seiser, R.; Liao, CH

    2015-01-01

    © 2015. A three-dimensional CFD model was developed to simulate the full-loop of a dual fluidized-bed biomass gasification system consisting of a gasifier, a combustor, a cyclone separator, and a loop-seal. This full-loop simulation includes the chemical kinetic modeling of biomass drying and pyrolysis, heterogeneous char reactions, and homogeneous gas-phase reactions. In the model, the gas phase is described using Large Eddy Simulation (LES) and the particle phase is described with the Multi...

  8. DEVELOPMENT AND EVALUATION OF A LOW-DENSITY BIOMASS FEEDING SYSTEM FOR FLUIDIZED BED GASIFIERS

    Directory of Open Access Journals (Sweden)

    A. E. Ghaly

    2013-01-01

    Full Text Available For efficient operation of a biomass gasifier, the biomass material must be fed continuously to the system. A feeding system for chopped straw and rice husk was designed, constructed and evaluated. It consisted of: a frame, a hopper, an auger, two agitators, a drive system and a power unit. Initial testing showed that wheat straw and rice husk, being highly cohesive materials, created tunnel flow and piping conditions. This occurs when the pressure above an impending dome of material is too small resulting in the creation of a stable dome and blockage of the discharge. In order to achieve good flow conditions, it was concluded that the hopper must operate under "mass outflow" and the material should not be allowed to build up along the flow channels. These objectives were achieved by the proper redesign of the hopper configuration, the installation of agitators in the hopper and use of an auger in the outlet duct leading into the gasifier. However, as the augur was used to move the biomass material from hopper to the gasifier, it was observed that hot gases leaked from the gasifier into the hopper and heat was also transmitted from the gasifier to the hopper though the augur shaft by conduction resulting in burning of biomass material in the hopper. Therefore, the augur shaft was fitted with copper tubing to serve as a water cooling system and the tapered section of the augur was fitted with a stainless steel section with water inlet and outlet to serve as a secondary cooling system. After, the system has been successfully modified for feeding wheat straw and rice husk, it was tested to determine the optimum operating conditions. Mass flow tests were performed with four sprocket combinations and four auger speeds. Increasing the auger speed and/or the lower agitator speed increased the straw output of the feeding system. However, increases in the upper agitator speed resulted in reduced mass flow of the material due to the mixing effect created

  9. Punctuated continuity: The technological trajectory of advanced biomass gasifiers

    International Nuclear Information System (INIS)

    Recent interest in biofuels and bio-refineries has been building upon the technology of biomass gasification. This technology developed since the 1980s in three periods, but failed to break through. We try to explain this by studying the technological development from a quasi-evolutionary perspective, drawing upon the concepts of technological paradigms and technological trajectories. We show that the socio-economic context was most important, as it both offered windows of opportunity as well as provided direction to developments. Changes in this context resulted in paradigm shifts, characterized by a change in considered end-products and technologies, as well as a change in companies involved. Other influences on the technological trajectory were firm specific differences, like the focus on a specific feedstock, scale and more recently biofuels to be produced. These were strengthened by the national focus of supporting policies, as well as specific attention for multiple technologies in policies of the USA and European Commission. Over each period we see strong variation that likely benefitted the long term development of the technology. Despite policy efforts that included variation and institutionalization, our case shows that the large changes in socio-economic context and the technological challenges were hard to overcome. - Highlights: • Advanced biomass gasification, as important enabling technology for biofuels and the bio-based economy, has been lacking success despite decades of research and development. • We try to explain this by reconstructing its technological trajectory. • We focus on processes of variation and selection, and interaction between local demonstration projects and the upcoming technological field. • The development of the technology over each period shows strong variation. • Long RD and D times in combination with major changes in the socio-economic context have resulted in discontinuities that even affected premium

  10. CO-FIRING COAL, FEEDLOT, AND LITTER BIOMASS (CFB AND LFB) FUELS IN PULVERIZED FUEL AND FIXED BED BURNERS

    Energy Technology Data Exchange (ETDEWEB)

    Kalyan Annamalai; John Sweeten; Saqib Mukhtar; Ben Thien; Gengsheng Wei; Soyuz Priyadarsan

    2002-01-15

    Intensive animal feeding operations create large amounts of animal waste that must be safely disposed of in order to avoid environmental degradation. Cattle feedlots and chicken houses are two examples. In feedlots, cattle are confined to small pens and fed a high calorie grain diet in preparation for slaughter. In chicken houses, thousands of chickens are kept in close proximity. In both of these operations, millions of tons of manure are produced every year. In this project a co-firing technology is proposed which would use manure that cannot be used for fertilizer, for power generation. Since the animal manure has economic uses as both a fertilizer and as a fuel, it is properly referred to as feedlot biomass (FB) for cow manure, or litter biomass (LB) for chicken manure. The biomass will be used a as a fuel by mixing it with coal in a 90:10 blend and firing it in existing coal fired combustion devices. This technique is known as co-firing, and the high temperatures produced by the coal will allow the biomass to be completely combusted. Therefore, it is the goal of the current research to develop an animal biomass cofiring technology. A cofiring technology is being developed by performing: (1) studies on fundamental fuel characteristics, (2) small scale boiler burner experiments, (3) gasifier experiments, (4) computer simulations, and (5) an economic analysis. The fundamental fuel studies reveal that biomass is not as high a quality fuel as coal. The biomass fuels are higher in ash, higher in moisture, higher in nitrogen and sulfur (which can cause air pollution), and lower in heat content than coal. Additionally, experiments indicate that the biomass fuels have higher gas content, release gases more readily than coal, and less homogeneous. Small-scale boiler experiments revealed that the biomass blends can be successfully fired, and NO{sub x} pollutant emissions produced will be similar to or lower than pollutant emissions when firing coal. This is a surprising

  11. CO-FIRING COAL, FEEDLOT, AND LITTER BIOMASS (CFB AND LFB) FUELS IN PULVERIZED FUEL AND FIXED BED BURNERS

    International Nuclear Information System (INIS)

    Intensive animal feeding operations create large amounts of animal waste that must be safely disposed of in order to avoid environmental degradation. Cattle feedlots and chicken houses are two examples. In feedlots, cattle are confined to small pens and fed a high calorie grain diet in preparation for slaughter. In chicken houses, thousands of chickens are kept in close proximity. In both of these operations, millions of tons of manure are produced every year. In this project a co-firing technology is proposed which would use manure that cannot be used for fertilizer, for power generation. Since the animal manure has economic uses as both a fertilizer and as a fuel, it is properly referred to as feedlot biomass (FB) for cow manure, or litter biomass (LB) for chicken manure. The biomass will be used a as a fuel by mixing it with coal in a 90:10 blend and firing it in existing coal fired combustion devices. This technique is known as co-firing, and the high temperatures produced by the coal will allow the biomass to be completely combusted. Therefore, it is the goal of the current research to develop an animal biomass cofiring technology. A cofiring technology is being developed by performing: (1) studies on fundamental fuel characteristics, (2) small scale boiler burner experiments, (3) gasifier experiments, (4) computer simulations, and (5) an economic analysis. The fundamental fuel studies reveal that biomass is not as high a quality fuel as coal. The biomass fuels are higher in ash, higher in moisture, higher in nitrogen and sulfur (which can cause air pollution), and lower in heat content than coal. Additionally, experiments indicate that the biomass fuels have higher gas content, release gases more readily than coal, and less homogeneous. Small-scale boiler experiments revealed that the biomass blends can be successfully fired, and NO(sub x) pollutant emissions produced will be similar to or lower than pollutant emissions when firing coal. This is a surprising

  12. 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

  13. Exergetic assessment of an integrated gasifier/boiler system for hydrogen production with different biomass types

    Energy Technology Data Exchange (ETDEWEB)

    Kalinci, Y. [Dokuz Eylul Univ., Izmir (Turkey). Izmir Vocational School; Hepbasli, A. [Ege Univ., Izmir (Turkey). Dept. of Mechanical Engineering; Dincer, I. [Univ. of Ontario Inst. of Technology, Oshawa, ON (Canada). Faculty of Engineering and Applied Science

    2009-07-01

    Biomass comprises all living matter present on earth and is derived from growing plants including algae, trees and crops or animal manure. It usually consists of carbon, hydrogen, oxygen and nitrogen. Sulfur is also present in small quantities, while some biomass consists of significant amounts of inorganic species. Biomass has the potential to accelerate the realization of hydrogen as a major fuel of the future. Since biomass is renewable and consumes atmospheric carbon dioxide (CO{sub 2}) during growth, it can have a small net CO{sub 2} impact compared to fossil fuels. However, hydrogen from biomass has major challenges as there are no completed technology demonstrations. In addition, the yield of hydrogen is low from biomass to biomass since the hydrogen content in biomass is low to begin with and the energy content is low due to the 40 percent oxygen content of biomass. This paper highlighted the importance of biomass-based syntactical gas and hydrogen production and reviewed the characteristics of six different biomass fuels used in various gasification systems and their energetic aspects and technical details. These fuels included almond shells; walnut prunings; rice straw; whole tree wood chips; sludge; and non-recyclable waste paper for hydrogen production from an integrated gasifier-boiler power system. The paper also presented a case study on biomass-based hydrogen production and assessed its thermodynamic performance through exergy. The results of the study were discussed through exergetic, irreversibility and improvement potential. It was concluded that the highest exergy rate was found for walnut pruning and almond shell. 15 refs., 6 tabs., 6 figs.

  14. Experimental Gasification of Biomass in an Updraft Gasifier with External Recirculation of Pyrolysis Gases

    Directory of Open Access Journals (Sweden)

    Adi Surjosatyo

    2014-01-01

    Full Text Available The updraft gasifier is a simple type of reactor for the gasification of biomass that is easy to operate and has high conversion efficiency, although it produces high levels of tar. This study attempts to observe the performance of a modified updraft gasifier. A modified updraft gasifier that recirculates the pyrolysis gases from drying zone back to the combustion zone and gas outlet at reduction zone was used. In this study, the level of pyrolysis gases that returned to the combustion zone was varied, and as well as measurements of gas composition, lower heating value and tar content. The results showed that an increase in the amount of pyrolysis gases that returned to the combustion zone resulted in a decrease in the amount of tar produced. An increase in the amount of recirculated gases tended to increase the concentrations of H2 and CH4 and reduce the concentration of CO with the primary (gasification air flow held constant. Increasing the primary air flow tended to increase the amount of CO and decrease the amount of H2. The maximum of lower heating value was 4.9 MJ/m3.

  15. Modeling and simulation of a downdraft biomass gasifier 1. Model development and validation

    International Nuclear Information System (INIS)

    An 'EQB' computer program for a downdraft gasifier has been developed to predict steady state performance. Moving porous bed of suction gasifier is modeled as one-dimensional (1-D) with finite control volumes (CVs), where conservation of mass, momentum and energy is represented by fluid flow, heat transfer analysis, drying, pyrolysis, oxidation and reduction reaction modules; which have solved in integral form using tri-diagonal matrix algorithm (TDMA) for reaction temperatures, pressure drop, energetics and product composition. Fluid flow module relates the flow rate with pressure drop, while biomass drying is described by mass transfer 1-D diffusion equation coupled with vapour-liquid-equilibrium relation. When chemical equilibrium is used in oxidation zone, the empirically predicted pyrolysis products (volatiles and char) and kinetic modeling approach for reduction zone constitutes an efficient algorithm allowing rapid convergence with adequate fidelity. Predictions for pressure drop and power output (gasifier) are found to be very sensitive, while gas composition or calorific value, temperature profile and gasification efficiency are less sensitive within the encountered range of gas flow rate.

  16. Test of different biomass into the IISc open-top co-current gasifier

    Energy Technology Data Exchange (ETDEWEB)

    Giordano, P. [Xylowatt SA, Chatel-St-Denis (Switzerland); Hasler, P. [Verenum SA, Zuerich (Switzerland); Dasappa, S. [Indian Institute of Science, Combustion Gasification and Propulsion Laboratory, Bangalore (India)

    2001-07-01

    This report made for the Swiss Federal Office of Energy (SFOE) describes the efforts made to demonstrate the technical feasibility of combined heat and power generation using wood gasification. The report describes a project involving a small open-top gasifier based on a design realised by the Indian Institute of Science (IISc). The tests made with various wood fuels such as clean wood chips, waste-wood chips, pecan nut shells, crushed oak briquettes, wood pellets, coffee hull pellets and chicken litter pellets are described and the results of measurements made concerning particulate matter, tar and certain organic compounds are presented. The discussion of the results shows that certain types of biomass can easily be used as a fuel for the small gasifier whereas others, such as coffee hull pellets, are less suitable. The report suggests that other possible fuels, such as olive and apricot stones, sludge from waste water treatment plant or plastic residue from refuse treatment should be tested in the gasifier. These tests could also provide the opportunity of testing appropriate gas treatment equipment at the same time.

  17. 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.)

  18. Method for online measurement of the CHON composition of raw gas from biomass gasifier

    International Nuclear Information System (INIS)

    Highlights: • Measuring the CHON composition of a raw gas by current methods is challenging. • An alternative method is to burn the raw gas before measuring the CHON composition. • The CHON contents of the raw gas can be accurately measured by the alternative method. • Measuring the CHON contents of the raw gas is now performed in a “one-step” analysis. • The new method is used to evaluate the operation of a dual fluidised bed gasifier. - Abstract: For unattended biomass gasification processes, rapid methods for monitoring the elemental composition (CHON) of the raw gas leaving the gasifier are needed. Conventional methods rely on time-consuming and costly laboratory procedures for analysing the condensable part of the raw gas. An alternative method, presented in this work, assesses the CHON composition of raw gas in a “one step” analysis without the need to previously characterise its chemical species composition. Our method is based on the quantitative conversion of a raw gas of complex chemical composition into CO2, H2O, and N2 in a small combustor. The levels of these simple species can be measured with high accuracy and good time resolution, and the CHON composition of the raw gas can be determined from the mass balance across the combustor. To evaluate this method, an online combustion facility was built and used to analyse the raw gas from the Chalmers 2-MWth dual fluidised bed steam gasifier. Test runs of the developed facility demonstrated complete combustion of the raw gas and the measurements were both fast and reliable. The new method used in combination with zero-dimensional reactor modelling provides valuable data for the operational monitoring of gasification processes, such as the degree of fuel conversion, composition of the char exiting the gasifier, oxygen transport by catalytic bed material, and amount of condensables in raw gas

  19. Perovskite sensing materials for syngas composition monitoring and biomass gasifier numerical model validation: A preliminary approach

    Science.gov (United States)

    Pallozzi, V.; Di Carlo, A.; Zaza, F.; Villarini, M.; Carlini, M.; Bocci, E.

    2016-06-01

    Biomass gasification represents a suitable choice for global environmental impact reduction, but more efforts on the process efficiency need to be conducted in order to enhance the use of this technology. Studies on inputs and outputs of the process, as well as measurements and controls of syngas composition and correlated organic and inorganic impurities, are crucial points for the optimization of the entire process: models of the system and sensing devices are, thus, very attractive for this purpose. In particular, perovskite based chemoresistive sensors could represent a promising technology, since their simplicity in function, relatively low cost and direct high temperature operation. The aim of this work is to develop a steam fluidized bed biomass gasifier model, for the prediction of the process gas composition, and new perovskite compounds, LaFeO3 based, as sensing material of chemoresistive sensors for syngas composition and impurities measurements. Chemometric analysis on the combustion synthesis via citrate-nitrate technique of LaFeO3 was also performed, in order to evaluate the relationship between synthesis conditions and perovskite materials and, thus, sensor properties. Performance of different sensors will be tested, in next works, with the support of the developed gasifier model.

  20. Sustainable model for financial viability of decentralized biomass gasifier based power projects

    International Nuclear Information System (INIS)

    This paper made a modest attempt for designing a sustainable model for financial viability of biomass gasifier power projects for enhancing electricity access in India and other developing countries. For long term sustainability of distributed generation projects in remote rural areas, viability from both project implementing agency (PIA) and the end-users need to be ensured. The minimum required prices of electricity from both PIA and end-user perspective have been estimated. While for PIA the cost recovery is the key for viability, the affordability to pay the electricity cost is crucial for the end users. Analysis carried out in this paper on the basis of data obtained from operational projects implemented in India reveal that it is essential to operate the system at a higher capacity utilization factor. While this can be achieved though creating convergence with locally relevant economic activity, it is also observed that micro-enterprises cannot pay beyond a certain price of electricity to keep it sustainable. This paper sets forth a case for developing a regulatory mechanism to extend the tariff fixation for the projects and providing cross-subsidies to ensure long term sustainability of off-grid project. - Highlights: → We design sustainable financial model for viability of biomass gasifier projects. → Analysis based on field data obtained from operational projects in India. Estimated electricity pricing from both implementing agency and end-users perspective. → A regulatory mechanism for tariff fixation and cross subsidization is recommended.

  1. Sustainable model for financial viability of decentralized biomass gasifier based power projects

    Energy Technology Data Exchange (ETDEWEB)

    Palit, Debajit, E-mail: debajitp@teri.res.in [Energy and Resources Institute, IHC Complex, Lodhi Road, New Delhi 110003 (India); Malhotra, Ramit, E-mail: ramit.malhotra@teri.res.in [Energy and Resources Institute, IHC Complex, Lodhi Road, New Delhi 110003 (India); Kumar, Atul, E-mail: atulk@teri.res.in [Energy and Resources Institute, IHC Complex, Lodhi Road, New Delhi 110003 (India); Copernicus Institute of Sustainable Development, Faculty of Geosciences, Utrecht University, P.O. Box 80115, 3508 TC Utrecht (Netherlands)

    2011-09-15

    This paper made a modest attempt for designing a sustainable model for financial viability of biomass gasifier power projects for enhancing electricity access in India and other developing countries. For long term sustainability of distributed generation projects in remote rural areas, viability from both project implementing agency (PIA) and the end-users need to be ensured. The minimum required prices of electricity from both PIA and end-user perspective have been estimated. While for PIA the cost recovery is the key for viability, the affordability to pay the electricity cost is crucial for the end users. Analysis carried out in this paper on the basis of data obtained from operational projects implemented in India reveal that it is essential to operate the system at a higher capacity utilization factor. While this can be achieved though creating convergence with locally relevant economic activity, it is also observed that micro-enterprises cannot pay beyond a certain price of electricity to keep it sustainable. This paper sets forth a case for developing a regulatory mechanism to extend the tariff fixation for the projects and providing cross-subsidies to ensure long term sustainability of off-grid project. - Highlights: > We design sustainable financial model for viability of biomass gasifier projects. > Analysis based on field data obtained from operational projects in India. Estimated electricity pricing from both implementing agency and end-users perspective. > A regulatory mechanism for tariff fixation and cross subsidization is recommended.

  2. Biomass-gasifier steam-injected gas turbine cogeneration for the cane sugar industry

    International Nuclear Information System (INIS)

    Steam injection for power and efficiency augmentation in aeroderivative gas turbines has been commercially established for natural gas-fired cogeneration since 1980. Steam-injected gas turbines fired with coal and biomass are being developed. A performance and economic assessment of biomass integrated-gasifier steam-injected gas turbine (BIG/STIG) cogeneration systems is carried out here. A detailed economic case study is presented for the second largest sugar factory in Jamaica, with cane residues as the fuel. BIG/STIG cogeneration units would be attractive investments for sugar producers, who could sell large quantities of excess electricity to the utility, or for the utility, as a low-cost generating option. Worldwide, the cane sugar industry could support some 50,000 MW of BIG/STIG electric generation capacity. The relatively modest development effort required to commercialize the BIG/STIG technology is discussed in a companion paper prepared for this conference

  3. 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.

  4. Effect of operating parameters on performance of an integrated biomass gasifier, solid oxide fuel cells and micro gas turbine system

    International Nuclear Information System (INIS)

    An integrated power system of biomass gasification with solid oxide fuel cells (SOFC) and micro gas turbine has been investigated by thermodynamic model. A zero-dimensional electrochemical model of SOFC and one-dimensional chemical kinetics model of downdraft biomass gasifier have been developed to analyze overall performance of the power system. Effects of various parameters such as moisture content in biomass, equivalence ratio and mass flow rate of dry biomass on the overall performance of system have been studied by energy analysis. It is found that char in the biomass tends to be converted with decreasing of moisture content and increasing of equivalence ratio due to higher temperature in reduction zone of gasifier. Electric and combined heat and power efficiencies of the power system increase with decreasing of moisture content and increasing of equivalence ratio, the electrical efficiency of this system could reach a level of approximately 56%.Regarding entire conversion of char in gasifier and acceptable electrical efficiency above 45%, operating condition in this study is suggested to be in the range of moisture content less than 0.2, equivalence ratio more than 0.46 and mass flow rate of biomass less than 20  kg h−1. - Highlights: • One-dimension chemical kinetics model of biomass gasifier has been developed. • Un-reacted char have been predicted along the height of the reduction zone of gasifier. • Effects of process parameters on char flow rate and efficiencies of BG, SOFC and GT system have been examined. • Regarding entire char conversion and acceptable system efficiency, the operating condition has been proposed

  5. Design improvements and performance testing of a biomass gasifier based electric power generation system

    International Nuclear Information System (INIS)

    The objective of the research work, reported in this paper is, to design and develop a down draft gasifier based power generation system of 75 KWe. A heat exchanger was designed and installed which recycles the waste heat of the hot gas, to improve the efficiency of the system. An improved ash removal system was introduced to minimize the charcoal removal rate from the reactor, to increase the gas production efficiency. A detailed analysis of the mass, energy and elemental balance is presented in the paper. The cold gas efficiency of the system is increased from 75.0% to 88.4%, due to the improvements made in the ash removal method. The Specific Fuel Consumption (SFC) rate of the system is 1.18 kg kWh−1. The energy conversion efficiency of the system, from fuel wood to electric power was found to be 18%. Significant increase in calorific value of the producer gas was achieved by supplying hot air for gasification. -- Highlights: •Design improvement of the system resulted 21.4% increase in cold gas efficiency (88.4%). •Mass, energy and elemental balance of a biomass gasifier system for power generation is analysed. •A heat exchanger is introduced in the system to recalculate the waste heat from the hot gas. •An innovative vibrating grate mechanism is designed and integrated with the gasifier system. •Specific Fuel Consumption is worked out to be 1.2 kg/kWh, which accounts for reduction of SFC to 20%

  6. Application of Exergoeconomic and Exergoenvironmental Analysis to an SOFC System with an Allothermal Biomass Gasifier

    Directory of Open Access Journals (Sweden)

    George Tsatsaronis

    2009-12-01

    Full Text Available

    In the future, energy conversion systems will be needed that reduce the environmental impact and costs of energy supply when fossil fuels are employed. An alternative is using biomass as a renewable energy resource to achieve both effects. For this reason, interest in biomass gasification processes resurged considerably in the past years. In particular, combination of allothermal biomass gasification with a high-temperature solid oxide fuel cell (SOFC has met with great interest as an attractive option for electricity generation. To objectively evaluate this new biomass conversion process, the newly developed exergoenvironmental analysis and the established exergoeconomic analysis are applied. The basic idea of both methods is that in energy conversion systems, exergy represents the only rational basis for assigning environmental impacts and costs to the energy carriers and to the inefficiencies within the system. The present article identifies the most relevant system components from the environmental and economic points of view and provides information about possibilities of design improvements. Comparison of the results of both methods reveals that the most relevant process components are the SOFC, the heat exchanger for preheating the air, and the allothermal fluidized-bed gasifier. A special focus will be placed on differences between both analysis methods.

    •  This paper is an updated version of a paper published in the ECOS'08 proceedings.

  7. Experimental Analysis of a Producer Gas Generated by a Chir Pine Needle (Leaf in a Downdraft Biomass Gasifier

    Directory of Open Access Journals (Sweden)

    Mr. Akhilesh Kumar

    2014-10-01

    Full Text Available Today’s Indian scenario is facing an unprecedented energy crisis as the conventional energy resources of India are consistently deteriorating with the limited stock of these natural minerals posing a staggering threat to the Indian economy. Among all the available resources biomass proves to be a satisfactory substitute for compensating the energy void due to these natural resources. Biomass is a renewable resource with almost zero net CO2 emission which is processed with the help of biomass gasifier which is concurrently used with a chir pine needle. The performance of the biomass gasifier system is evaluated in terms of equivalence ratio, producer gas composition, calorific value of the producer gas, gas production rate and cold gas efficiency. The experimental results are compared with those reported in the literature.

  8. CO-FIRING COAL: FEEDLOT AND LITTER BIOMASS (CFB AND CLB) FUELS IN PULVERIZED FUEL AND FIXED BED BURNERS

    Energy Technology Data Exchange (ETDEWEB)

    Kalyan Annamalai; John Sweeten; Saqib Mukhtar; Ben Thein; Gengsheng Wei; Soyuz Priyadarsan; Senthil Arumugam; Kevin Heflin

    2003-08-28

    Intensive animal feeding operations create large amounts of animal waste that must be safely disposed of in order to avoid environmental degradation. Cattle feedlots and chicken houses are two examples. In feedlots, cattle are confined to small pens and fed a high calorie grain-diet diet in preparation for slaughter. In chicken houses, thousands of chickens are kept in close proximity. In both of these operations, millions of tons of manure are produced every year. The manure could be used as a fuel by mixing it with coal in a 90:10 blend and firing it in an existing coal suspension fired combustion systems. This technique is known as co-firing, and the high temperatures produced by the coal will allow the biomass to be completely combusted. Reburn is a process where a small percentage of fuel called reburn fuel is injected above the NO{sub x} producing, conventional coal fired burners in order to reduce NO{sub x}. The manure could also be used as reburn fuel for reducing NO{sub x} in coal fired plants. An alternate approach of using animal waste is to adopt the gasification process using a fixed bed gasifier and then use the gases for firing in gas turbine combustors. In this report, the cattle manure is referred to as feedlot biomass (FB) and chicken manure as litter biomass (LB). The report generates data on FB and LB fuel characteristics. Co-firing, reburn, and gasification tests of coal, FB, LB, coal: FB blends, and coal: LB blends and modeling on cofiring, reburn systems and economics of use of FB and LB have also been conducted. The biomass fuels are higher in ash, lower in heat content, higher in moisture, and higher in nitrogen and sulfur (which can cause air pollution) compared to coal. Small-scale cofiring experiments revealed that the biomass blends can be successfully fired, and NO{sub x} emissions will be similar to or lower than pollutant emissions when firing coal. Further experiments showed that biomass is twice or more effective than coal when

  9. Exergetic assessment of an integrated gasifier/boiler system for hydrogen production with different biomass types

    International Nuclear Information System (INIS)

    In this study, we utilize some experimental data taken from the literature, especially on the air blown gasification characteristics of six different biomass fuels, namely almond shell (ASF), walnut pruning (WPF), rice straw (RSF), whole tree wood chips (WWF), sludge (SLF) and non-recyclable waste paper (NPF) for hydrogen production from an integrated gasifier-boiler power system. Then, we undertake an exergy analysis of this integrated system and assess its performance through energy and exergy efficiencies. The exergy content values calculated for the biomass fuels range from 15.89 to 22.07 MJ/kg. The stack gas is examined at cyclone out, and the hydrogen concentrations determined change between 7 and 18 (%v/v) for NPF and ASF. Furthermore, the system considered is studied in terms of irreversibility and improvement potential rates. These rate values change from 6.82 to 43.11 kW for irreversibility and 6.01 to 41.24 kW for improvement potential, respectively. The exergy efficiencies of the system are calculated as 4.33 to 11.89%. Finally, we consider N and NH3 contents of the six biomass fuels and their stack gas compositions. (author)

  10. Thermodynamic Model of a Very High Efficiency Power Plant based on a Biomass Gasifier, SOFCs, and a Gas Turbine

    Directory of Open Access Journals (Sweden)

    P V Aravind

    2012-07-01

    Full Text Available Thermodynamic calculations with a power plant based on a biomass gasifier, SOFCs and a gas turbine are presented. The SOFC anode off-gas which mainly consists of steam and carbon dioxides used as a gasifying agent leading to an allothermal gasification process for which heat is required. Implementation of heat pipes between the SOFC and the gasifier using two SOFC stacks and intercooling the fuel and the cathode streams in between them has shown to be a solution on one hand to drive the allothermal gasification process and on the other hand to cool down the SOFC. It is seen that this helps to reduce the exergy losses in the system significantly. With such a system, electrical efficiency around 73% is shown as achievable.

  11. Energy study of the energy supply systems for isolated communities in Cuba from the use of biomass gasifiers downdraft

    International Nuclear Information System (INIS)

    At work a comprehensive energy analysis of plants generating electricity from the gasification of various biomass that currently conceived by the management of the Electric Union for the electrification of isolated communities in the fields of Cuba is made. For this, based on the properties of the main biomass available, the calculations needed are performed to evaluate the efficiency of the gasifier and other components of energy transformation system. The power generation are taken into consideration and an assessment of the needs of biomass in each case is made. (full text)

  12. Synergy effects of the co-combustion of biomass and sewage sludge with coal in the CFB combustor of Stadtwerke Duisburg AG

    Energy Technology Data Exchange (ETDEWEB)

    Wischnewski, R.; Werther, J. [Hamburg Univ. of Tech. (Germany). Inst. of Solids Process Engineering and Particle Technology; Heidenhof, N. [Stadtwerke Duisburg AG, Duisburg (Germany)

    2006-07-01

    In the framework of an EU-funded research project, co-combustion tests of biomass and waste in the coal-fired circulating fluidised bed (CFB) combustor of Stadtwerke Duisburg AG were performed. The aim of the study was to investigate whether positive synergy effects with respect to the overall emissions of the plant and its operating behaviour could be detected. Local measurements of gas and solids concentrations as well as fluid dynamic parameters were performed in the combustion chamber in addition to the measurements with the measurement devices of the plant. (orig.)

  13. 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.

  14. Gasification of biomass wastes in an entrained flow gasifier: Effect of the particle size and the residence time

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, Juan J.; Aranda-Almansa, Guadalupe [Universidad de Castilla-La Mancha, Departamento de Mecanica Aplicada e Ingenieria de Proyectos, Escuela Tecnica Superior de Ingenieros Industriales (Edificio Politecnico), Avenida Camilo Jose Cela s/n, 13071 Ciudad Real (Spain); Bula, Antonio [Universidad del Norte, Departamento de Ingenieria Mecanica, Km.5 Antigua Via Puerto Colombia, Barranquilla (Colombia)

    2010-06-15

    Experimental tests in an entrained flow gasifier have been carried out in order to evaluate the effect of the biomass particle size and the space residence time on the gasifier performance and the producer gas quality. Three types of biomass fuels (grapevine pruning and sawdust wastes, and marc of grape) and a fossil fuel (a coal-coke blend) have been tested. The results obtained show that a reduction in the fuel particle size leads to a significant improvement in the gasification parameters. The thermochemical characterisation of the resulting char-ash residue shows a sharp increase in the fuel conversion for particles below 1 mm diameter, which could be adequate to be used in conventional entrained flow gasifiers. Significant differences in the thermochemical behaviour of the biomass fuels and the coal-coke blend have been found, especially in the evolution of the H{sub 2}/CO ratio with the space time, mainly due to the catalytic effect of the coal-coke ash. The reaction temperature and the space time have a significant effect on the H{sub 2}/CO ratio (the relative importance of each of these parameters depending on the temperature), this value being independent of the fuel particle size. (author)

  15. Biomass gasifier projects for decentralized power supply in India: A financial evaluation

    International Nuclear Information System (INIS)

    Results of a techno-economic evaluation of biomass gasifier based projects for decentralized power supply for remote locations in India are presented. Contributions of different components of diesel engine generator (DG) sets, dual fuel (DF) engine generator sets and 100% producer gas (HPG) engine generator sets to their capital costs as well as to the levelized unit cost of electricity (LUCE) delivered by the same have been analyzed. LUCE delivered to the consumers has been estimated to be varying in the range of Rs. 13.14-24.49/kWh (US$ 0.30-0.55/kWh) for DF BGPP. LUCE increases significantly if BGPP is operated at part loads. Presently available 40kW capacity HPG systems in India are expected to be financially competitive with a DG set of equivalent capacity beyond a break-even diesel price of Rs. 34.70/l. It is expected to be financially more attractive than an equivalent capacity DF BGPP for diesel prices of more than Rs. 44.29/l. In certain specific conditions operating two smaller capacity systems has been found to be attractive as against a single larger capacity system

  16. 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.

  17. Scaling Up Biomass Gasifier Use in India; BarriersInterventions & Remedies: A Review

    OpenAIRE

    Mr. Ritesh U.Nrupekar; Prof. Rajesh B.Choksi

    2014-01-01

    In India, work on gasifiers for energy applications started in the early 1980s. These efforts received a boost with the Department of Non-conventional Energy Sources‟ (DNES, latter MNES, now a ministry, MNRE) dissemination program that was initiated in 1987. While this subsidy-based program was successful in placing about 1200 gasifier systems for irrigation pumping in the field, most of these units were non-operational soon after for lots of reasons. Despite all this, large-scale gasifier de...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-12-31

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

  19. Scaling Up Biomass Gasifier Use in India; BarriersInterventions & Remedies: A Review

    Directory of Open Access Journals (Sweden)

    Mr. Ritesh U.Nrupekar

    2014-06-01

    Full Text Available In India, work on gasifiers for energy applications started in the early 1980s. These efforts received a boost with the Department of Non-conventional Energy Sources‟ (DNES, latter MNES, now a ministry, MNRE dissemination program that was initiated in 1987. While this subsidy-based program was successful in placing about 1200 gasifier systems for irrigation pumping in the field, most of these units were non-operational soon after for lots of reasons. Despite all this, large-scale gasifier deployment has still not taken off in India. The fact that scale -up did not take place automatically even in cases where gasifiers are economically clearly feasible indicates that there are a number of issues to be considered and barriers to be overcome for successful large-scale deployment. To facilitate gasifier deployment among poorer and nonskilled users (i.e., unorganized, small-scale firms, rural areas; and lack of systematic programs targeted towards scale-up. Especially important is the fact that the particulars of implementing gasifier-based energy systems depend on the kind of application and context; therefore the approach has to be tailored to the specific application – this impedes the potential success of any single approach to scale-up.

  20. Thermo-economic optimization of a Solid Oxide Fuel Cell – Gas turbine system fuelled with gasified lignocellulosic biomass

    International Nuclear Information System (INIS)

    Highlights: • Biomass gasification combined with SOFC–GT hybrid system was studied. • Syngas hot cleaning unit is used in order to improve the efficiency of the system. • Energy integration in order to recover the maximum heat available inside the process. • Multi-objective optimization maximizing the efficiency and minimizing the capital investment costs. - Abstract: Within the context of sustainable energy supply and CO2 emissions reduction a Solid Oxide Fuel Cell (SOFC) – gas turbine hybrid system, fuelled with gasified woody biomass is studied in detail for small and medium scale applications (100 kWth,BM and 8 MWth,BM of dry biomass input). The system consists of an air dryer unit, a gasifier, a hot cleaning section made of a particulate removal unit (cyclone and candle filter) and a two-stage tar removal unit, a SOFC and a gas turbine with optional CO2 capture. This modern technology has the advantage of using a renewable and CO2-neutral source and to be economically competitive at medium scales. The competitiveness of different process options is systematically compared by applying a coherent approach combining flowsheeting, energy integration and economic evaluation in a multi-objective optimization framework. This analysis reveals the importance of process integration maximizing the heat recovery and valorizing the waste heat, by cogeneration for example. The studied process options include direct and indirect circulating fluidized bed gasifier (using respectively oxygen or steam as gasification agent) and Viking gasifier, atmospheric or pressurized systems and optional pre-reforming in the hot gas cleaning. To close the thermal energy balance, a fraction of the produced syngas can be burnt. The energy integration results reveal that the steam production for the gasification and reforming are key parameters (S/B and S/C ratio) defining the process performance. A multi-objective optimization maximizing the efficiency and minimizing the capital

  1. CFB boilers in multifuel application

    International Nuclear Information System (INIS)

    Fuel flexibility characteristic for CFB boilers plays an important rule in industrial and utility size applications. Possibility to use wider range of fuels that has been long time considered as by-products or wastes and possibility to design boilers able to operate with alternative fuels is an important factor that improves fuel delivery security and plant economy. Presented article is based on similar publications that present Foster Wheeler's experience in design and delivery of the CFB boilers for wide range of coals and cofiring by- products of crude oil refining and coal processing. Aspects of biomass cofiring will be also presented. (author)

  2. 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.

  3. Performance evaluation of atmospheric biomass integrated gasifier combined cycle systems under different strategies for the use of low calorific gases

    International Nuclear Information System (INIS)

    This work aims at a performance evaluation of atmospheric BIGCC (biomass integrated gasifier combined cycle) systems operating under different strategies for the use of low calorific fuel in gas turbines. The fuel is a synthetic gas derived from gasification of sugar cane residues. Two analysed strategies for surge control on gas turbines originally designed for operation on natural gas are de-rating and air extraction from the compressor. Another strategy for use of biomass derived gas is the retrofit of a gas turbine through modification of the expander geometry. Three generic gas turbines, whose main parameters have been taken from off the shelf machines, are proposed as representative of certain classes of gas turbines. Results are compared to the hypothetical situation in which it is possible to accept any increase in gas turbine pressure ratio. According to the results, de-rating is the worst surge control strategy, both from the point of view of power production and thermal efficiency. Conversely, results showed considerable gains that can be obtained on cycle power production when the gas turbine expander is modified. Additionally, an overview of issues concerning the suitability of sugar cane residues (bagasse and trash) for the production of gasified gas and its use in BIGCC plants is presented

  4. Ground tests of 120 kW(heat) biomass fired gasifier diesel installation

    Energy Technology Data Exchange (ETDEWEB)

    Zyssin, L.V.; Maronet, I.J.; Morshin, V.N. [Energotechnology Ltd., St. Petersburg (Russian Federation)

    1996-12-31

    For the 1 MW and less power range diesel gasifier power plants could be considered as one of the main energy sources. The brief information about works carried out in Russia according to this direction is presented. Data of preliminary tests for gas diesel installations are presented. (orig.)

  5. Decreased PCDD/F formation when co-firing a waste fuel and biomass in a CFB boiler by addition of sulphates or municipal sewage sludge

    International Nuclear Information System (INIS)

    Highlights: • Two strategies to reduce PCDD/F formation when co-firing solid recovered fuel (SRF) and biomass. • They were co-combustion with municipal sewage sludge (MSS) and addition of ammonium sulphate. • PCDD/Fs were significantly reduced for a biomass rich in chlorine when adding ammonium sulphate. • MSS had a suppressing effect on PCDD/F formation during co-combustion with SRF. • A link is presented between gaseous alkali chlorides, chlorine in deposits and PCDD/F formation. - Abstract: Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are formed during waste incineration and in waste-to-energy boilers. Incomplete combustion, too short residence times at low combustion temperatures (th circulating fluidised bed (CFB) boiler. The PCDD/F concentrations in the raw gas after the convection pass of the boiler and in the fly ashes were compared. The fuel types were a so-called clean biomass with low content of chlorine, biomass with enhanced content of chlorine from supply of PVC, and solid recovered fuel (SRF) which is a waste fuel containing higher concentrations of both chlorine, and catalysing metals. The PCDD/F formation increased for the biomass with enhanced chlorine content and it was significantly reduced in the raw gas as well as in the fly ashes by injection of ammonium sulphate. A link, the alkali chloride track, is demonstrated between the level of alkali chlorides in the gas phase, the chlorine content in the deposits in the convection pass and finally the PCDD/F formation. The formation of PCDD/Fs was also significantly reduced during co-combustion of SRF with municipal sewage sludge (MSS) compared to when SRF was fired without MSS as additional fuel

  6. Validation of Continuous CHP Operation of a Two-Stage Biomass Gasifier

    DEFF Research Database (Denmark)

    Ahrenfeldt, Jesper; Henriksen, Ulrik Birk; Jensen, Torben Kvist;

    2006-01-01

    The Viking gasification plant at the Technical University of Denmark was built to demonstrate a continuous combined heat and power operation of a two-stage gasifier fueled with wood chips. The nominal input of the gasifier is 75 kW thermal. To validate the continuous operation of the plant, a 9-day...... measurement campaign was performed. The campaign verified a stable operation of the plant, and the energy balance resulted in an overall fuel to gas efficiency of 93% and a wood to electricity efficiency of 25%. Very low tar content in the producer gas was observed: only 0.1 mg/Nm3 naphthalene could be...... measured in raw gas. A stable engine operation on the producer gas was observed, and very low emissions of aldehydes, N2O, and polycyclic aromatic hydrocarbons were measured....

  7. BIOMASS-FUELED, SMALL-SCALE, INTEGRATED-GASIFIER, GAS-TURBINE POWER PLANT: PROGRESS REPORT ON THE PHASE 2 DEVELOPMENT

    Science.gov (United States)

    The paper reports the latest efforts to complete development of Phase 2 of a three-phase effort to develop a family of small-scale (1 to 20 MWe) biomass-fueled power plants. The concept envisioned is an air-blown pressurized fluidized-bed gasifier followed by a dry hot gas clean...

  8. Decreased PCDD/F formation when co-firing a waste fuel and biomass in a CFB boiler by addition of sulphates or municipal sewage sludge.

    Science.gov (United States)

    Åmand, Lars-Erik; Kassman, Håkan

    2013-08-01

    Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are formed during waste incineration and in waste-to-energy boilers. Incomplete combustion, too short residence times at low combustion temperatures (<700 °C), incineration of electronic waste and plastic waste containing chlorine are all factors influencing the formation of PCDD/Fs in boilers. The impact of chlorine and catalysing metals (such as copper and iron) in the fuel on PCDD/F formation was studied in a 12 MW(th) circulating fluidised bed (CFB) boiler. The PCDD/F concentrations in the raw gas after the convection pass of the boiler and in the fly ashes were compared. The fuel types were a so-called clean biomass with low content of chlorine, biomass with enhanced content of chlorine from supply of PVC, and solid recovered fuel (SRF) which is a waste fuel containing higher concentrations of both chlorine, and catalysing metals. The PCDD/F formation increased for the biomass with enhanced chlorine content and it was significantly reduced in the raw gas as well as in the fly ashes by injection of ammonium sulphate. A link, the alkali chloride track, is demonstrated between the level of alkali chlorides in the gas phase, the chlorine content in the deposits in the convection pass and finally the PCDD/F formation. The formation of PCDD/Fs was also significantly reduced during co-combustion of SRF with municipal sewage sludge (MSS) compared to when SRF was fired without MSS as additional fuel. PMID:23684693

  9. Decreased PCDD/F formation when co-firing a waste fuel and biomass in a CFB boiler by addition of sulphates or municipal sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Åmand, Lars-Erik [Chalmers University of Technology, Department of Energy and Environment, Gothenburg (Sweden); Kassman, Håkan, E-mail: hakan.kassman@vattenfall.com [Vattenfall Research and Development AB, Nyköping (Sweden)

    2013-08-15

    Highlights: • Two strategies to reduce PCDD/F formation when co-firing solid recovered fuel (SRF) and biomass. • They were co-combustion with municipal sewage sludge (MSS) and addition of ammonium sulphate. • PCDD/Fs were significantly reduced for a biomass rich in chlorine when adding ammonium sulphate. • MSS had a suppressing effect on PCDD/F formation during co-combustion with SRF. • A link is presented between gaseous alkali chlorides, chlorine in deposits and PCDD/F formation. - Abstract: Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are formed during waste incineration and in waste-to-energy boilers. Incomplete combustion, too short residence times at low combustion temperatures (<700 °C), incineration of electronic waste and plastic waste containing chlorine are all factors influencing the formation of PCDD/Fs in boilers. The impact of chlorine and catalysing metals (such as copper and iron) in the fuel on PCDD/F formation was studied in a 12 MW{sub th} circulating fluidised bed (CFB) boiler. The PCDD/F concentrations in the raw gas after the convection pass of the boiler and in the fly ashes were compared. The fuel types were a so-called clean biomass with low content of chlorine, biomass with enhanced content of chlorine from supply of PVC, and solid recovered fuel (SRF) which is a waste fuel containing higher concentrations of both chlorine, and catalysing metals. The PCDD/F formation increased for the biomass with enhanced chlorine content and it was significantly reduced in the raw gas as well as in the fly ashes by injection of ammonium sulphate. A link, the alkali chloride track, is demonstrated between the level of alkali chlorides in the gas phase, the chlorine content in the deposits in the convection pass and finally the PCDD/F formation. The formation of PCDD/Fs was also significantly reduced during co-combustion of SRF with municipal sewage sludge (MSS) compared to when SRF was fired without MSS

  10. Technical and economic assessment of producing hydrogen by reforming syngas from the Battelle indirectly heated biomass gasifier

    International Nuclear Information System (INIS)

    The technical and economic feasibility of producing hydrogen from biomass by means of indirectly heated gasification and steam reforming was studied. A detailed process model was developed in ASPEN Plus trademark to perform material and energy balances. The results of this simulation were used to size and cost major pieces of equipment from which the determination of the necessary selling price of hydrogen was made. A sensitivity analysis was conducted on the process to study hydrogen price as a function of biomass feedstock cost and hydrogen production efficiency. The gasification system used for this study was the Battelle Columbus Laboratory (BCL) indirectly heated gasifier. The heat necessary for the endothermic gasification reactions is supplied by circulating sand from a char combustor to the gasification vessel. Hydrogen production was accomplished by steam reforming the product synthesis gas (syngas) in a process based on that used for natural gas reforming. Three process configurations were studied. Scheme 1 is the full reforming process, with a primary reformer similar to a process furnace, followed by a high temperature shift reactor and a low temperature shift reactor. Scheme 2 uses only the primary reformer, and Scheme 3 uses the primary reformer and the high temperature shift reactor. A pressure swing adsorption (PSA) system is used in all three schemes to produce a hydrogen product pure enough to be used in fuel cells. Steam is produced through detailed heat integration and is intended to be sold as a by-product

  11. Co-gasification of biomass and coal in a pressurised fluidised bed gasifier

    Energy Technology Data Exchange (ETDEWEB)

    Andries, L.; Hein, K.R.G. [Lab. for Thermal Power Engineering, Dept. of Mechanical Engineering and Marine Technology, Delft Univ. of Technology (Netherlands)

    1996-12-31

    The Laboratory for Thermal Power Engineering of the Delft University of Technology is participating in an EU funded, international, R + D project which is designed to aid European industry in addressing issues regarding co-utilisation of biomass and/or waste in advanced coal conversion processes. The project comprises three main programmes, each of which includes a number of smaller subprogrammes. The three main programmes are: Coal-biomass systems component development and design; Coal-biomass environmental studies; Techno-economic assessment studies. (orig)

  12. 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...

  13. Study of biomass combustion characteristics for the development of a catalytic combustor/gasifier

    OpenAIRE

    Dody, Joseph W.

    1985-01-01

    The research reported here explored, a "new" approach to biomass energy conversion for small-scale process heat-applications. The conversion process uses close-coupled catalytic. combustion to burn combustibles in effluent generated by primary combustion or gasification of biomass fuels. Computer control of primary and secondary air flow rates allow control of the devices output power while maintaining fuel-lean or stoichiometric conditions in the effluent entering the catalytic combustion...

  14. Economic scales for first-generation biomass-gasifier/gas turbine combined cycles fueled from energy plantations

    International Nuclear Information System (INIS)

    This paper assesses the scales at which commercial, first-generation biomass integrated-gasifier/gas turbine combined cycle (BIG/GTCC) technology is likely to be most economic when fueled by plantation-derived biomass. First-generation BIG/GTCC systems are likely to be commercially offered by vendors beginning around 2000 and will be based on either pressurized or atmospheric-pressure gasification. Both plant configurations are considered here, with estimates of capital and operating costs drawn from published and other sources. Prospective costs of a farm-grown energy crop (switchgrass) delivered to a power plant are developed with the aid of a geographic information system (GIS) for agricultural regions in the North Central and Southeast US in the year 2000 and 2020. A simplified approach is applied to estimate the cost of delivering chipped eucalyptus from an existing plantation in Northeast Brazil. The optimum capacity (MWopt), defined as that which yields the minimum calculated cost of electricity (COEm), varies by geographic region due to differences in delivered biomass costs. With pressurized BIG/GTCC plants, MWopt is in the range of 230--320 MWe for the sites considered, assuming most of the land around the power plant is farmed for energy crop production. For atmospheric-pressure BIG/GTCC plants, MWopt ranges from 110 to 142 MWe. When a lower fraction of the land around a plant is used for energy farming, values for MWopt are smaller than these. In all cases, the cost of electricity is relatively insensitive to plant capacity over a wide range around MWopt

  15. Adaptive monitoring of emissions in energy boilers using self-organizing maps: An application to a biomass-fired CFB (circulating fluidized bed)

    International Nuclear Information System (INIS)

    Improvement of energy efficiency, reduction of operating costs, and reduction of harmful emissions released into the atmosphere are issues of major concern in modern energy plants. While air emissions have to be restricted due to tightening environmental legislation, at the same time it is ever more important to be able to respond quickly to any changes in the load demand or fuel quality. As unpredictability increases with changing fuel quality and more complex operational strategies, undesired phenomena such as increased emission release rates may become more likely. Therefore, it is crucial that emission monitoring systems are able to adapt to varying conditions, and advanced methodologies are needed for monitoring and decision-support. In this paper a novel approach for advanced monitoring of emissions in CFB (circulating fluidized bed) boilers is described. In this approach a model based on SOM (self-organizing maps) is updated regularly to respond to the prevailing condition of the boiler. After creating each model a new set of measurements is input to the system, and the current state of the process is determined using vector distance calculation. Finally, the system evaluates the current condition and may alert if a preset limit defined for each emission component is exceeded. - Highlights: • An adaptive monitoring approach based on self-organizing maps is presented. • The system can monitor the current state of a combustion process and its emissions. • The system is designed to alert when the preset limits defined for emissions are exceeded. • Due to regular updating routine the system is able to adapt to changing conditions. • The application is demonstrated using data from a biomass-fired energy boiler

  16. ALTENER - Biomass event in Finland

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    The publication contains the lectures held in the Biomass event in Finland. The event was divided into two sessions: Fuel production and handling, and Co-combustion and gasification sessions. Both sessions consisted of lectures and the business forum during which the companies involved in the research presented themselves and their research and their equipment. The fuel production and handling session consisted of following lectures and business presentations: AFB-NETT - business opportunities for European biomass industry; Wood waste in Europe; Wood fuel production technologies in EU- countries; new drying method for wood waste; Pellet - the best package for biofuel - a view from the Swedish pelletmarket; First biomass plant in Portugal with forest residue fuel; and the business forum of presentations: Swedish experiences of willow growing; Biomass handling technology; Chipset 536 C Harvester; KIC International. The Co-combustion and gasification session consisted of following lectures and presentations: Gasification technology - overview; Overview of co-combustion technology in Europe; Modern biomass combustion technology; Wood waste, peat and sludge combustion in Enso Kemi mills and UPM-Kymmene Rauma paper mill; Enhanced CFB combustion of wood chips, wood waste and straw in Vaexjoe in Sweden and Grenaa CHP plant in Denmark; Co-combustion of wood waste; Biomass gasification projects in India and Finland; Biomass CFB gasifier connected to a 350 MW{sub t}h steam boiler fired with coal and natural gas - THERMIE demonstration project in Lahti (FI); Biomass gasification for energy production, Noord Holland plant in Netherlands and Arbre Energy (UK); Gasification of biomass in fixed bed gasifiers, Wet cleaning and condensing heat recovery of flue gases; Combustion of wet biomass by underfeed grate boiler; Research on biomass and waste for energy; Engineering and consulting on energy (saving) projects; and Research and development on combustion of solid fuels

  17. 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

  18. Study tour to biomass gasifiers in Germany; Studiereis naar biomassavergassingsinstallaties in Duitsland

    Energy Technology Data Exchange (ETDEWEB)

    Knoef, H.A.M. [BTG Biomass Technology Group, Enschede (Netherlands)

    2000-12-01

    A study trip to a biomass gasification plant in Germany took place from 13-15 November 2000. The goal of the trip was to obtain information on German developments, experience, and possibilities in the field of biomass gasification. The participants were representatives of Dutch parties in the energy sector: waste sector, manufacturers, producers, policy makers and consultants. The most important feature was the visit to plants that were in operation. Due in particular to the new EEG (Emeuerbare-Energien-Gesetz/Renewable Energy) legislation, German policy makers have created an initial market for sustainable energy with a degree of success. The key feature is that EEG makes projects 'bankable' by guaranteeing a return delivery compensation. An EEG-type scheme designed to accelerate the development of sustainable energy could be an interesting instrument also for the Netherlands. The plan was to visit four plants and have a number of presentations in a period of three days. Preference was for relatively new plants with differing concepts. The following plants were visited and/or presented: 200-kWe CHP wood gasification plant, based on AHT technology, located at Domsland in Eckenfoerde; a 10,000 tonnes/year wood gasification plant, based on 'cupola furnace' technology of blast furnaces, located at Holzhausen near Leipzig; a 1-MWe wood gasification plant, based on Carbo-V technology, located at Freiberg; and finally a 23-MWe CBP wood gasification plant, also based on Juch technology, located at Siebenlehn. In clearly appears that Germany is ahead of the Netherlands in the realisation of gasification plants. Still, there are certain problems with the reliability of operation. The plants selected were relatively new (with the possible exception of Espenhain) and they are having too many teething problems. Sound insight has been obtained into the various concepts of decentralised energy generation from biomass and how this can be fitted into the

  19. 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.

  20. Modeling and simulation of combined pyrolysis and reduction zone for a downdraft biomass gasifier

    International Nuclear Information System (INIS)

    This paper simulates the behavior of a global fixed bed biomass gasification reactor. The pyrolysis zone and reduction zone models are combined to simulate the global process of biomass gasification. The volatiles and gases released from the pyrolysis zone were assumed to crack into equivalent amounts of CO, CH4 and H2O. It is considered that the volatiles and gases leave the pyrolysis zone instantaneously and enter the reduction zone as initial gas concentrations. The numerical method applied is a Runge-Kutta fourth order method for solution of the pyrolysis zone model and finite differences for the reduction zone model to solve numerically the coupled ordinary differential equations. Simulations are performed for the varying pyrolysis temperature with a heating rate of 25 K/min and constant temperature of 1400 K as the initial reduction zone temperature at the same time. The simulation results for the temperature and concentrations of the gaseous species are in good agreement with published experimental data

  1. Biomass Gasifier Energy Cyber-Physical System Design with Coupling of the Wind and Solar Energy

    Directory of Open Access Journals (Sweden)

    Zhihuan Zhang

    2013-07-01

    Full Text Available The air pollution in China has been quite serious, and biomass is extremely rich in large agricultural country. In the view of current situation, highly efficient solar collectors, wind energy and solar energy coupled heating straw gasification system is studied. The stability of continuous gas production is analyzed in various weather conditions including windy, calm, sunny and cloudy. Highly efficient solar panels, wind energy and solar energy coupled heating straw gasification control system is raised. This system overcomes the time variability of the weather conditions to ensure the stability of the continuous gas production under a variety of weather conditions. It has high quality of gas production, strong anti-interference ability and robustness.

  2. Process integration and optimization of a solid oxide fuel cell – Gas turbine hybrid cycle fueled with hydrothermally gasified waste biomass

    International Nuclear Information System (INIS)

    Due to its suitability for using wet biomass, hydrothermal gasification is a promising process for the valorization of otherwise unused waste biomass to synthesis gas and biofuels. Solid oxide fuel cell (SOFC) based hybrid cycles are considered as the best candidate for a more efficient and clean conversion of (bio) fuels. A significant potential for the integration of the two technologies is expected since hydrothermal gasification requires heat at 673–773 K, whereas SOFC is characterized by heat excess at high temperature due to the limited electrochemical fuel conversion. This work presents a systematic process integration and optimization of a SOFC-gas turbine (GT) hybrid cycle fueled with hydrothermally gasified waste biomass. Several design options are systematically developed and compared through a thermodynamic optimization approach based on First Law and exergy analysis. The work demonstrates the considerable potential of the system that allows for converting wet waste biomass into electricity at a First Law efficiency of up to 63%, while simultaneously enabling the separation of biogenic carbon dioxide for further use or sequestration. -- Highlights: ► Hydrothermal gasification is a promising process for the valorization of waste wet biomass. ► Solid Oxide Fuel Cell – Gas Turbine hybrid cycle emerges as the best candidates for conversion of biofuels. ► A systematic process integration and optimization of a SOFC-GT hybrid cycle fuelled with hydrothermally gasified biomass is presented. ► The system may convert wet waste biomass to electricity at a First Law efficiency of 63% while separating the biogenic carbon dioxide. ► The process integration enables to improve the First Law efficiency of around 4% with respect to a non-integrated system.

  3. 140 g H{sub 2}/kg biomass d.a.f. by a CO-shift reactor downstream from a FB biomass gasifier and a catalytic steam reformer

    Energy Technology Data Exchange (ETDEWEB)

    Corella, Jose; Molina, Gregorio; Toledo, Jose M. [Department of Chemical Engineering, University ' ' Complutense' ' of Madrid, 28040 Madrid (Spain); Aznar, Maria P.; Caballero, Miguel A. [Chemical and Environmental Engineering Department, CPS, 3 Maria de Luna st., University of Saragossa, 50018 Saragossa (Spain)

    2008-04-15

    The effect of adding a CO-shift reactor downstream from a fluidized bed biomass gasifier and a steam reforming catalytic reactor is studied in this paper. The upstream gasifier was of small pilot plant scale, 10 kg biomass/h. Therefore, the downstream catalytic reactors, steam reformer and CO-shift, operated under a real gasification gas. The gasifying agent used was H{sub 2}O-O{sub 2} mixtures. The CO-shift catalytic reactor used had one high (HT) and one low temperature (LT) adiabatic beds. Two commercial catalysts were used throughout the process. CO-conversions (eliminations) were higher than 90% and a H{sub 2}-content as high as 73 vol%, dry basis, were obtained by the CO-shift system. This H{sub 2} content is equivalent to a yield of 140gH{sub 2}/kg biomass d.a.f. The CO conversion and the increase (up to 14 vol%) of the H{sub 2} content, correlate well with the molar steam/CO ratio in the gasification gas at the inlet of the HT bed. (author)

  4. 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)

  5. Mathematical Modelling of Gradient Chain Biomass Gasifier%梯度链条式生物质气化炉数值模拟

    Institute of Scientific and Technical Information of China (English)

    蔡建军; 王清成; 王全

    2015-01-01

    According to the biomass gasification discipline, biomass gasification process is divided into four stages in gra-dient chain biomass gasifier.Thus can control gasification conditions in different gasification stage.Mathematical modeling methods have been employed to simulate a gradient chain biomass gasifier, not only the temperature, concentra-tion distributing of the top of bed in different conditions, but also gasification character of gasifier chamber were calcula ted, by varying the ratio of actual air fuel ratio and stoichiometric air fuel ratio( ER) .The results showed that the tem-perature, concentration distributing( CO, CH4 , C2 H4 , Cn Hm , H2 ) , carbon conversion efficiency, HLV of the gas fuel, gasification efficiency vary in the range of 622.24℃,CO 13.81%,CH4 3.26%,C2 H4 0.601%,C2 H6 0.002%,Cn Hm 10.936%, H2 3.82%, 75.1%, 5501 kJ/Nm3 , 57.56%, and this effect of gasification better than downdraft fixed bed gasifier, a fixed-bed gasifier and bubbling bed gasifier.%梯度链条式生物质气化炉按照气化规律从空间上将生物质气化过程分为4个阶段,可实现对各气化阶段气化条件进行控制。为此,对梯度链条式生物质气化炉进行数值模拟,通过改变ER ,计算出不同 ER 下床层顶部各组分的温度和浓度分布及炉膛气相的气化特性。模拟结果显示:气化合成气出口温度622.24℃;气化合成气中CO为13.81%、CH4为3.26%、C2H4为0.601%、C2H6为0.002%、CnHm为10.936%、H2为3.82%;碳转化效率为75.1%,低位热值为5501 kJ/Nm3,气化效率为57.56%。该气化效果比下吸式固定床气化炉、固定床气化炉及鼓泡床气化炉空气气化效果好。

  6. Condensate from a two-stage gasifier

    DEFF Research Database (Denmark)

    Bentzen, Jens Dall; Henriksen, Ulrik Birk; Hindsgaul, Claus

    2000-01-01

    Condensate, produced when gas from downdraft biomass gasifier is cooled, contains organic compounds that inhibit nitrifiers. Treatment with activated carbon removes most of the organics and makes the condensate far less inhibitory. The condensate from an optimised two-stage gasifier is so clean...... compounds and the level of inhibition are so low that condensate from the optimised two-stage gasifier can be led to the public sewer....

  7. Advanced CFB for clean and efficient coal power

    Energy Technology Data Exchange (ETDEWEB)

    H. Nevalainen; J. Saastamoinen; M. Jegoroff (and others) [VTT, Jyvaskyla (Finland)

    2009-07-01

    The European Union's Clefco project (2004-06) aimed to promote the development of once through steam cycle (OTSC) CFB technology. This was carried out by increasing the process knowledge that is essential for successful boiler design and demonstration of the multi-fuel flexibility of the process. To fulfil the development needs of OTSC CFB technology, a comprehensive understanding of CFB combustion processes needed to be achieved. Intensive research in laboratory, pilot and full-scale combustors was required to fulfil the abovementioned objectives. In the project, each partner worked in its own field of research. Cooperation between partners enabled the best-possible understanding of the process. In order to study different process characteristics and verify measurements and simulations, experiments were carried out with different size reactors - VTT's laboratory scale CFB reactor, VTT's 50 kW pilot CFB reactor, Chalmers' 12 MW CFB boiler, cold rig and several commercial boilers. To find out possibilities for end-use of ash, national legislations and standards were studied. Knowledge was applied to ash management possibilities for coal combustion and co-combustion of coal and biomass. The studies were based on the ash characterisation, which was carried out for ash samples collected during the projects' combustion tests. 52 refs., 122 figs., 42 tabs.

  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. Experimental numerical study utilizing CFD in a stratified gasifier operating with biomass; Estudio numerico experimental de un gasificador estratificado que opera con biomasa, utilizando CFD

    Energy Technology Data Exchange (ETDEWEB)

    Rogel Ramirez, Alejandro

    2007-07-01

    The central idea behind this work is the developing of a numeric-experimental model, useful to optimize the biomass stratified gasifier design. Firstly, model validation will be carried up by comparison with reference experimental data available. This study describes a 1-D + 2-D numerical model used to simulate the gasification of pine wood pellets in a stratified downdraft gasifier whereby Eulerian conservation equations are solved for particle and gas phase components, velocities and specific enthalpies. The model takes into account the biomass particle process such as heating up, drying, primary pyrolysis of biomass, secondary pyrolysis of tar, homogeneous reactions and heterogeneous combustion/gasification reactions, and particle size change. This CFD model can be used to predict temperature profiles, gas composition, producer gas lower heating value, and carbon conversion efficiency, and the reactor performance when operating parameters and feed properties are changed. The standard {kappa}-{epsilon} and RNG {kappa}-{epsilon} models were used to simulate the turbulent flow conditions. [Spanish] La idea central del presente trabajo es el desarrollo de un modelo numerico- experimental, para optimizar el diseno de gasificadores estratificados de biomasa. Primeramente, el modelo sera validado utilizando datos experimentales disponibles en la literatura. Este estudio describe un modelo numerico 1-D+2-D, utilizado para simular la gasificacion de 'pelets' de madera de pino en un gasificador estratificado de flujos paralelos, en el que se resuelven ecuaciones de conservacion Eulerianas para los componentes de la fase gaseosa, la fase solida, velocidades y entalpias especificas. El modelo considera procesos como: calentamiento, secado de la biomasa, pirolisis primaria de la madera, pirolisis secundaria de los alquitranes, reacciones homogeneas, reacciones heterogeneas de combustion/gasificacion y cambio en el tamano de la particula. Este modelo CFD puede ser

  10. The importance of SO{sub 2} and SO{sub 3} for sulphation of gaseous KCl - An experimental investigation in a biomass fired CFB boiler

    Energy Technology Data Exchange (ETDEWEB)

    Kassman, Haakan [Vattenfall Power Consultant AB, Nykoeping (Sweden); Chalmers University of Technology, Department of Energy and Environment, Division of Energy Technology, Gothenburg (Sweden); Baefver, Linda [Technical Research Institute of Sweden, Energy Technology, Boraas (Sweden); Aamand, Lars-Erik [Chalmers University of Technology, Department of Energy and Environment, Division of Energy Technology, Gothenburg (Sweden)

    2010-09-15

    This paper is based on results obtained during co-combustion of wood pellets and straw in a 12 MW circulating fluidised bed (CFB) boiler. Elemental sulphur (S) and ammonium sulphate ((NH{sub 4}){sub 2}SO{sub 4}) were used as additives to convert the alkali chlorides (mainly KCl) to less corrosive alkali sulphates. Their performance was then evaluated using several measurement tools including, IACM (on-line measurements of gaseous alkali chlorides), a low-pressure impactor (particle size distribution and chemical composition of extracted fly ash particles), and deposit probes (chemical composition in deposits collected). The importance of the presence of either SO{sub 2} or SO{sub 3} for gas phase sulphation of KCl is also discussed. Ammonium sulphate performed significantly better than elemental sulphur. A more efficient sulphation of gaseous KCl was achieved with (NH{sub 4}){sub 2}SO{sub 4} even when the S/Cl molar ratio was less than half compared to sulphur. Thus the presence of gaseous SO{sub 3} is of greater importance than that of SO{sub 2} for the sulphation of gaseous KCl. (author)

  11. Chemical reactions in combustion of peat and biomass in two fluidized-bed boilers, CFB (25 MW) and BFB (25 MW) at Oestersund. The effect on SO2- and NOx-emissions by operating conditions and type of fuel

    International Nuclear Information System (INIS)

    Most of the air pollutants are emitted from different combustion processes and much work is therefore needed to reduce these emissions. The processes are however extremely complex and to be able to study them, fundamental chemical and physical principles have to be taken into account. The aim of the present work has been to show the importance of equilibrium chemistry to improve the knowledge of specific combustion problems as well as the processes as a whole. This will also increase the possibilities to reduce the pollutants. The measured values from two combustion units (CFB and BFB, 25 MW) show good agreement with the corresponding calculated equilibrium values. The following are some of the more important results obtained: - By co-firing peat with biomass, the total SO2 emissions can be reduced. The effects of variations in temperature and oxygen level on the SO2 emissions are also reported; - The NOx emission levels agree well with the equilibrium levels, that is they increase with temperature and oxygen levels. Therefore, the amount of nitrogen in the fuel has shown to have insignificant effect in these experiments; - Initial levels of N2O are effectively reduced by high temperatures (> 950 deg Centigrade). (Orig.). ( 36 refs., 26 figs., 18 tabs.)

  12. Hot and Dry Cleaning of Biomass-Gasified Gas Using Activated Carbons with Simultaneous Removal of Tar, Particles, and Sulfur Compounds

    Directory of Open Access Journals (Sweden)

    Kinya Sakanishi

    2012-05-01

    Full Text Available This study proposes a gas-cleaning process for the simultaneous removal of sulfur compounds, tar, and particles from biomass-gasified gas using Fe-supported activated carbon and a water-gas shift reaction. On a laboratory scale, the simultaneous removal of H2S and COS was performed under a mixture of gases (H2/CO/CO2/CH4/C2H4/N2/H2S/COS/steam. The reactions such as COS + H2 → H2S + CO and COS + H2O → H2S + CO2 and the water-gas shift reaction were promoted on the Fe-supported activated carbon. The adsorption capacity with steam was higher than that without steam. On a bench scale, the removal of impurities from a gas derived from biomass gasification was investigated using two activated filters packed with Fe-supported activated carbon. H2S and COS, three- and four-ring polycyclic aromatic hydrocarbons (PAHs, and particles were removed and a water-gas shift reaction was promoted through the first filter at 320–350 °C. The concentrations of H2S and COS decreased to less than 0.1 ppmv. Particles and the one- and two-ring PAHs, except for benzene, were then removed through the second filter at 60–170 °C. The concentration of tar and particles decreased from 2428 to 102 mg Nm−3 and from 2244 to 181 mg Nm−3, respectively.

  13. Modeling of a biomass high temperature steam gasifier integrated with assisted solar energy and a micro gas turbine

    International Nuclear Information System (INIS)

    Highlights: • A parametric study determines optimal system requirements for different feedstock. • The effect that biomass and moisture levels have on syngas composition is analyzed. • The novel system proposed optimizes heat recovery and water consumption. • Competitive solar efficiency is obtained at low steam to biomass ratios. • Overall CHP utilization factors range between 30% and 43%. - Abstract: A mathematical model that describes a trailer scale biomass steam gasification system coupled with a solar collector heat source and a micro gas turbine is reported in this paper. This combined heat and power system is set to a prescribed output of 20 kWe and several system conditions have been optimized in a parametric study to minimize resource consumption rates. Biomass feeding rates under optimal conditions were found to range between 23 and 63 kg/h depending on the types of feedstock and other parameters. Water consumption is reduced through a condensation and recirculation process that is part of a heat recovery unit. Also, solar energy requirements have been reduced by means of a recuperator that extracts heat out of the combustion products. The overall system performance has been evaluated by a utilization factor which was found to range between 30% and 43%. The system has been compared to a baseline case of an air breathing gasification system of a similar scale. It was found that steam gasification produces the syngas with heating values over twice as high as those obtained by air gasification. Steam gasification also led to a 25% and 50% reduction in emission rates of contaminants like CO2 and nitrogen oxides respectively relative to the baseline case

  14. Purchase of power by State Electricity Boards from biomass gasifier systems: formulating a long term national policy

    International Nuclear Information System (INIS)

    Current policy for purchase of power from renewable sources of energy by State Electricity Boards in India is examined and certain changes in that policy are suggested. State Electricity Boards are reluctant to buy power from renewables as such a purchase is seen by the Boards as being of against their economic interests. But if socio-environmental and climatological costs of power of thermal plants are taken into consideration, it becomes imperative that a long term policy for power purchase from renewables by electricity boards will have to be followed. Such a policy is outlined. After giving formulae for unit cost of generation from thermal power plants, diesel generation (DG) sets and biomass gasification, it is recommended that basis for the purchase price for power generated through biomass gas should be the cost of generation through DG sets or cost of generation through biomass gasification whichever is lower. A clause for automatic price escalation should also be a part of such policy. Some measures to compensate electricity boards for purchase of power from renewables are suggested. They include levying of a special surcharge by boards on their electricity sales and funding by the Central Government. (M.G.B.)

  15. CFD modelling of an open core downdraft moving bed biomass gasifier; Modelado de un gasificador estratificado de lecho movil de biomasa, utilizando CFD

    Energy Technology Data Exchange (ETDEWEB)

    Rogel-Ramirez, A [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico)]. E-mail: ARogelR@iingen.unam.mx

    2008-10-15

    This paper contains the description of a bidimensional Computational Fluid Dynamics (CFD), model Developer to simulate the flow and reaction in a stratified downdraft biomass gasifier, whereby Eulerian conservation equations are solved for particle and gas phase components, velocities and specific enthalpies. The model is based on the PHOENICS package and represents a tool which can be used in gasifier analysis and design. Contributions of chemical kinetics and the mixing rate using the EBU approach are considered in the gas phase global homogeneous reactions. The harmonic blending of chemical kinetics and mass transfer effects, determine the global heterogeneous reactions between char and O{sub 2}, CO{sub 2} and H{sub 2}O. The turbulence effect in the gas phase is accounted by the standard {kappa}-{epsilon} approach. The model provides information of the producer gas composition, velocities and temperature at the outlet, and allows different operating parameters and feed properties to be changed. Finally, a comparison with experimental data available in literature was done, which showed satisfactory agreement from a qualitative point of view, though further validation is required. [Spanish] Este estudio describe un modelo numerico bidimensional, basado en Dinamica de Fluidos Computacional (CFD), desarrollado para simular el flujo y las reacciones que ocurren en un gasificador estratificado de flujos paralelos, en el que se resuelven ecuaciones de conservacion Eulerianas para los componentes de la fase gaseosa, la fase solida, velocidades y entalpias especificas. El modelo esta basado en el codigo PHOENICS y representa una herramienta que puede ser utilizada en el analisis y diseno de gasificadores. En las reacciones globales homogeneas se consideran las contribuciones de la cinetica quimica y la rapidez de mezclado, usando el modelo Eddy Brake-UP (EBU). La medida harmonica de la cinetica quimica y la transferencia de masa, determinan las velocidades globales de

  16. Demanding fuel combustion. Metso CFB multifuel boiler experience in Stora Enso Ostroleka

    Energy Technology Data Exchange (ETDEWEB)

    Kulesza, Rafal [Stora Enso Poland S.A., Ostroleka (Poland)

    2013-04-01

    Stora Enso Poland erected a combined cycle power plant for supplying its Ostroleka mill with power and heat. The central component is a circulating fluidised bed combustion (CFB) boiler designed for multi-fuel combustion like biomass and residues of the paper mill. The thermal rating of the CFB boiler amounts to 164 MW and two turbines supply up to 43 MW of power. (orig.)

  17. 1300°F 800 MWe USC CFB Boiler Design Study

    Science.gov (United States)

    Robertson, Archie; Goidich, Steve; Fan, Zhen

    Concern about air emissions and the effect on global warming is one of the key factors for developing and implementing new advanced energy production solutions today. One state-of-the-art solution is circulating fluidized bed (CFB) combustion technology combined with a high efficiency once-through steam cycle. Due to this extremely high efficiency, the proven CFB technology offers a good solution for CO2 reduction. Its excellent fuel flexibility further reduces CO2 emissions by co-firing coal with biomass. Development work is under way to offer CFB technology up to 800MWe capacities with ultra-supercritical (USC) steam parameters. In 2009 a 460MWe once-through supercritical (OTSC) CFB boiler designed and constructed by Foster Wheeler will start up. However, scaling up the technology further to 600-800MWe with net efficiency of 45-50% is needed to meet the future requirements of utility operators. To support the move to these larger sizes, an 800MWe CFB boiler conceptual design study was conducted and is reported on herein. The use of USC conditions (˜11 00°F steam) was studied and then the changes, that would enable the unit to generate 1300°F steam, were identified. The study has shown that by using INTREX™ heat exchangers in a unique internal-external solids circulation arrangement, Foster Wheeler's CFB boiler configuration can easily accommodate 1300°F steam and will not require a major increase in heat transfer surface areas.

  18. 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)

  19. 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

  20. A rice husk gasifier for paddy drying

    International Nuclear Information System (INIS)

    Due to energy crisis and constant increase in the price of fossil fuels, the world's trend changes to renewable sources of energy like solar, wind and biomass gasification. Substantial biomass potential is available in Pakistan in the form of agriculture or forest residue (rice straw, rice husk, cotton stalks, corn cobs, wood chips, wood saw, etc.). These can be best utilised for the production of producer gas or synthetic gas that can be used for drying of agricultural crops. The drying process is an important activity of post harvest processing for long-term storage. Rice husk is nowadays commonly used for biomass gasification and its heat content value is about 15MJ/kg. It constitutes about 30 percent of rice production. A rice husk gasifier was developed and evaluated on paddy drying at Japan International Cooperation Agency (JICA), Tsukuba International Center (TBIC), Japan. Rice husk gasifier has following major components; husk feeding system, ash chamber, burner, centrifugal fan, drying chamber, gasifier reactor, air duct and an electric motor of 0.37kW. The average drying plenum air temperature was recorded as 45 degree C during the drying process. The paddy 'IR 28' from initial moisture content of 24% was dried up to 14% moisture content for about 3.33h consuming 3kg/h of rice husk. The efficiency was found to be 58%. The rice husk gasifier can also be used for drying the fruits and vegetables, provided that heat exchanger should be attached with it. The overall performance of rice husk gasifier was satisfactory and will be beneficial for small scale farmers, food processors and millers as well. (author)

  1. High Temperature Air/Steam Gasification (HTAG) Of Biomass – Influence of Air/Steam flow rate in a Continuous Updraft Gasifier

    OpenAIRE

    Arif, Muhammad Jalil

    2013-01-01

    Biomass is an important source of energy and the most important fuel worldwide after coal, oil and natural gas. Biomass does not add carbon dioxide to the atmosphere as it absorbs the same amount of carbon in growing as it releases when consumed as a fuel. Its advantage is that it can be used to generate electricity with the same equipment or power plants that are now burning fossil fuels. However, the low energy density of the biomass requires developments and advances in conversion technolo...

  2. Process Integration and Optimization of a Solid Oxide Fuel Cell – Gas Turbine Hybrid Cycle fuelled with Hydrothermally Gasified Waste Biomass

    OpenAIRE

    Facchinetti, Emanuele; Gassner, Martin; D'Amelio, Matilde; Maréchal, François; Favrat, Daniel

    2012-01-01

    Due to its suitability for using wet biomass, hydrothermal gasification is a promising process for the valorization of otherwise unused waste biomass to synthesis gas and biofuels. Solid oxide fuel cell (SOFC) based hybrid cycles are considered as the best candidate for a more efficient and clean conversion of (bio)fuels. A significant potential for the integration of the two technologies is expected since hydrothermal gasification requires heat at 673-773 K, whereas SOFC is characterized by ...

  3. Sensitivity of Fischer-Tropsch Synthesis and Water-Gas Shift Catalystes to Poisons form High-Temperature High-Pressure Entrained-Flow (EF) Oxygen-Blown Gasifier Gasification of Coal/Biomass Mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Burton Davis; Gary Jacobs; Wenping Ma; Khalid Azzam; Janet ChakkamadathilMohandas; Wilson Shafer

    2009-09-30

    There has been a recent shift in interest in converting not only natural gas and coal derived syngas to Fischer-Tropsch synthesis products, but also converting biomass-derived syngas, as well as syngas derived from coal and biomass mixtures. As such, conventional catalysts based on iron and cobalt may not be suitable without proper development. This is because, while ash, sulfur compounds, traces of metals, halide compounds, and nitrogen-containing chemicals will likely be lower in concentration in syngas derived from mixtures of coal and biomass (i.e., using entrained-flow oxygen-blown gasifier gasification gasification) than solely from coal, other compounds may actually be increased. Of particular concern are compounds containing alkali chemicals like the chlorides of sodium and potassium. In the first year, University of Kentucky Center for Applied Energy Research (UK-CAER) researchers completed a number of tasks aimed at evaluating the sensitivity of cobalt and iron-based Fischer-Tropsch synthesis (FT) catalysts and a commercial iron-chromia high temperature water-gas shift catalyst (WGS) to alkali halides. This included the preparation of large batches of 0.5%Pt-25%Co/Al{sub 2}O{sub 3} and 100Fe: 5.1Si: 3.0K: 2.0Cu (high alpha) catalysts that were split up among the four different entities participating in the overall project; the testing of the catalysts under clean FT and WGS conditions; the testing of the Fe-Cr WGS catalyst under conditions of co-feeding NaCl and KCl; and the construction and start-up of the continuously stirred tank reactors (CSTRs) for poisoning investigations.

  4. Emission characterization for a down draft gasifier

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Charles Denys da Luz; Nogueira, Manoel Fernandes Martins [Federal University of Para (UFPA), Belem, PA (Brazil). Lab. de Engenharia Mecanica], E-mail: mfmn@ufpa.br

    2010-07-01

    Gasification is the thermal-chemical conversion of biomass into combustible gas, which can be used as combustion fuel in internal combustion motors or syngas with applications across the chemical industry. To check the performance of a gasifier one needs to quantify the contained energy in the produced gas as well as the quantity of produced carbon for the calculation of mean energy efficiency and the carbon conversion factor of the gas using experimentally obtained data. Energy efficiency is quantified value that describes the relationship between the respective quantities of energy contained in the biomass used and the gas produced, in the same sense, the carbon conversion is a quantity of carbonaceous compounds present in used biomass and the amount of carbon in the produced gas. The present document evaluates the energy efficiency and the carbon conversion factor of a prototype model of a downdraft gasifier from India that was modified by a local company. The nominal parameters of the gasifier's function are as follows: gas production capacity running on 45 kW, biomass consumption (acai seeds) of 15 kg/h. The gasifier dimensions are as follows: diameter of 150 mm and height of 2000 mm. The energy efficiency and the carbon conversion rate are quantified, the pressure loss due to the bed reactor and the temperature of the gases are also measured at the reactor exit; the tar, particle composite and non-condensable gas (CO, CO{sub 2}, CH{sub 4}, SO{sub 2}, N{sub 2} e NO{sub x}) concentrations were measured in the produced gas at the cleaning process. (author)

  5. Energetic evaluation of low potential biomass gasifier coupled with a burner of the produced gas for generation of heat; Avaliacao energetica de um gaseificador de biomassa de baixa potencia, associado a um combustor do gas produzido, para geracao de calor

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Samuel [Universidade de Brasilia (FAV/UNB), DF (Brazil). Fac. de Agronomia e Medicina Veterinaria], email: samuelmartin@unb.nr; Silva, Jadir Nogueira [Universidade Federal de Vicosa (UFV), MG (Brazil). Dept. de Engenharia Agricola; Machado, Cassio Silva; Zanatta, Fabio Luis; Galvarro, Svetlana F.S. [Universidade Federal de Vicosa (UFV), MG (Brazil)

    2011-07-01

    In the search of alternatives for sustainable socio-economic development, this study had the objective of evaluating the energetic performance of a concurrent flow biomass gasifier associated with a burner for the gas produced which was of low potential for air heating using a renewable energy source (substituting non-renewable). In this system 4 tests were performed using eucalyptus chips (tests 1 and 2) and logs (tests 3 and 4) as fuel, for the two fan motor frequencies of 60 and 50 hertz. Temperature in the combustion chamber was monitored, along with fuel consumption and other variables. In the tests, the average exhaust air temperature was maintained between 92.7 and 100.4 deg C, and the reduction in the motor frequency from 60 to 50 Hz caused an increase in the duration of the tests. The system presented the best energetic performance when utilizing a frequency of 60 Hz for both fuel types. However, the results of energy efficiency varied very little when comparing tests performed at the same fan frequency. Thus, the gasification process was little affected by variation in the physical characteristics of the tested fuels, and it was recommended that the equipment operate with a frequency of 60 Hz. (author)

  6. Characterization of Inorganic Elements in Woody Biomass Bottom Ash from a Fixed-bed Combustion System, a Downdraft Gasifier and a Wood Pellet Burner by Fractionation

    OpenAIRE

    Adrian K. James; Steve S. Helle; Thring, Ronald W.; Gurkaran S. Sarohia; P. Michael Rutherford

    2014-01-01

    The direct combustion of biomass residues produces large quantities of bottom ash. Environmental sustainable management requires that ash recycling should be carried out whenever possible. Suitable applications of bottom ash are based predominantly on its chemical properties. The presence of major ash forming and trace elements along with other intrinsic properties unique to bottom ash, suggest its potential as a soil additive. But, ash quality must be of a high standard to prevent environmen...

  7. Methodology for sizing, energy analysis and selection of equipment for a biomass gasifier to drive an internal combustion engine; Metodologia de dimensionamento, analise energetica e selecao de equipamentos de um gaseificador de biomassa para o acionamento de um motor de combustao interna

    Energy Technology Data Exchange (ETDEWEB)

    Coronado, Christian Rodriguez; Silveira, Jose Luz [Universidade Estadual Paulista (FEG/UNESP), Guaratingueta, SP (Brazil). Fac. de Engenharia], e-mails: christian@feg.unesp.br, joseluz@feg.unesp.br; Arauzo, Jesus Perez [University of Zaragoza (UNIZAR), Zaragoza (Spain). Centro Politecnico Superior. Chemical and Environmental Engineering Dept.], e-mail: qtarauzo@unizar.es

    2006-07-01

    Alter both oil crisis, of 1973 and 1979, a bad effect of the elevated costs and continuously increment of the oil prices was noted, for this reason, the interest for renewable energies sources widely available in developing countries was increased. All over the world, governments have formulated main objectives for energies savings and search for friendly technologies, taking into account the effects related with the environment. The imminent scarcity of fossil fuels has made humanity the rational use of primary energies, as a result of these; new plants with improved technology have been conceived taking into account energy savings and efficiency improvement. In this context, biomass gasification technologies are important, since they consist in techniques of parallel production of electricity and heat from just one fuel. This work consists in the development of a gasifier down draft of 100 kW for an internal combustion engine, which includes its sizing process and its energy analysis. The sizing includes design facts and the parameters of the conditioning systems for the exhaust gas. This part is mainly based in the experience of a work group of the Zaragoza State University - Spain, UNIZAR, specialists in the construction of small down draft gasifiers, for every case, air will be used as a gasifier agent and as biomass forestall. The availability of biomass resources and the application of the national energetic view system are relevant. The gasifier will have a 100 kg/h of feeding, the energetic analysis includes the matter and energy balance and the respective efficient such cold as hot efficient of the exhaust gas. Moreover it will be tried the equipment recommended for the cleaning and conditioning of this gas fuel for this equipment in particular. (author)

  8. Sensitivity of Fischer-Tropsch Synthesis and Water-Gas Shift Catalysts to Poisons from High-Temperature High-Pressure Entrained-Flow (EF) Oxygen-Blown Gasifier Gasification of Coal/Biomass Mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Burton Davis; Gary Jacobs; Wenping Ma; Dennis Sparks; Khalid Azzam; Janet Chakkamadathil Mohandas; Wilson Shafer; Venkat Ramana Rao Pendyala

    2011-09-30

    There has been a recent shift in interest in converting not only natural gas and coal derived syngas to Fischer-Tropsch synthesis products, but also converting biomass-derived syngas, as well as syngas derived from coal and biomass mixtures. As such, conventional catalysts based on iron and cobalt may not be suitable without proper development. This is because, while ash, sulfur compounds, traces of metals, halide compounds, and nitrogen-containing chemicals will likely be lower in concentration in syngas derived from mixtures of coal and biomass (i.e., using entrained-flow oxygen-blown gasifier gasification gasification) than solely from coal, other compounds may actually be increased. Of particular concern are compounds containing alkali chemicals like the chlorides of sodium and potassium. In the first year, University of Kentucky Center for Applied Energy Research (UK-CAER) researchers completed a number of tasks aimed at evaluating the sensitivity of cobalt and iron-based Fischer-Tropsch synthesis (FT) catalysts and a commercial iron-chromia high temperature water-gas shift catalyst (WGS) to alkali halides. This included the preparation of large batches of 0.5%Pt-25%Co/Al{sub 2}O{sub 3} and 100Fe: 5.1Si: 3.0K: 2.0Cu (high alpha) catalysts that were split up among the four different entities participating in the overall project; the testing of the catalysts under clean FT and WGS conditions; the testing of the Fe-Cr WGS catalyst under conditions of co-feeding NaCl and KCl; and the construction and start-up of the continuously stirred tank reactors (CSTRs) for poisoning investigations. In the second and third years, researchers from the University of Kentucky Center for Applied Energy Research (UK-CAER) continued the project by evaluating the sensitivity of a commercial iron-chromia high temperature water-gas shift catalyst (WGS) to a number of different compounds, including KHCO{sub 3}, NaHCO{sub 3}, HCl, HBr, HF, H{sub 2}S, NH{sub 3}, and a combination of H

  9. A combined system comprising a biomass gasifier and a Stirling engine. Design and optimisation for continuous operation; Eine Anlagenkombination aus Biomassevergaser und Stirlingmotor. Anlagendesign und Auslegung fuer den Dauerbetrieb

    Energy Technology Data Exchange (ETDEWEB)

    Huelscher, Manfred [Qalovis Farmer Automatic Energy GmbH, Laer (Germany)

    2010-07-01

    Conventional wood gasifiers consist of a gasifier, gas filter, and internal combustion engine. The contribution presents a novel system comprising a gasifier, burner, and Stirling engine. To enhance the electric efficiency, the burner is operated with air preheated via reculperation. The Stirling characteristic is known, and the gasification/combustion system can be calculated and designed on the basis of the Stirling data. The dust problem of the Stirling heat exchanger is solved by an automatic filter system, so that low-maintenance long-term operation becomes possible.

  10. Using fuzzy logic to control the power of a biomass gasifier ventilation system motor to ensure suitable oxidation temperature for tar cracking; Uso da logica fuzzy para controle da potencia do motor do sistema de ventilacao de um gaseificador de biomassa que assegure temperatura de oxidacao adequada para craqueamento do alcatrao

    Energy Technology Data Exchange (ETDEWEB)

    Rezende, Oscar L.T.; Kulitz, Hans H. [Instituto Federal de Educacao, Ciencia e Tecnologia do Espirito Santo (IFES), Vitoria, ES (Brazil)], email: oscar@ifes.edu.br; Silva, Jadir N.; Galvarro, Svetlana F.S. [Universidade Federal de Vicosa (UFV), MG (Brazil). Dept. de Engenharia Agricola; Martin, Samuel [Universidade de Brasilia (FAV/UNB), DF (Brazil). Fac. de Agronomia e Medicina Veterinaria

    2011-07-01

    There are several models of biomass gasifier. The one used in this study was the concurrent model, in which fuel is fed through the top and air feed occurs in descending flow through combustion and reduction zones, producing low-tar gas. Nevertheless, total tar burning must be ensured in order to produce a gas, suitable for several applications. This study aimed at developing a fuzzy-based algorithm to control the active power applied to a gasifier ventilation system motor, which can ensure adequate oxidation temperature for cracking tar that may be present in the gas produced. The input variables of the fuzzy controller were oxidation zone temperature and the variation rate of this temperature. The output variable was active power. The rule base was created using experimental data. The tests performed with this algorithm allowed observing that the oxidation temperature can be set to a value desired, which does not occur in gasification processes without ventilation system control. (author)

  11. Gasification of hazelnut shells in a downdraft gasifier

    Energy Technology Data Exchange (ETDEWEB)

    Dogru, M.; Howarth, C.R.; Akay, G.; Keskinler, B. [University of Newcastle (United Kingdom). Dept. of Chemical and Process Engineering; Malik, A.A. [Waste to Energy Ltd., Sudbury (United Kingdom)

    2002-05-01

    The potential offered by biomass to reduce greenhouse gas production is now being more widely recognised. The energy in biomass may be realised either by direct combustion use, or by upgrading into more valuable and usable products such as gas, fuel oil and higher value products for utilisation in the chemical industry or for clean power generation. Up till now, gasification work has concentrated on woody biomass but recently sources of other biomass with large energy production potential have been identified, namely hazelnut shells. Therefore, a pilot scale downdraft gasifier is used to investigate gasification potential of hazelnut shells. A full mass balance is reported including the tar production rate as well as the composition of the produced gas as a function of feed rate. Additionally, the effect of feed rate on the CV/composition of the product gas and the associated variations of gasifier zone temperatures are determined with temperatures recorded throughout the main zones of the gasifier and also at the gasifier outlet and gas cleaning zones. Pressure drops are also measured across the gasifier and gas cleaning system because the produced gas may be used in conjunction with a power production engine when it is important to have low pressure drop in the system. The quality of the product gas is found to be dependent on the smooth flow of the fuel and the uniformity of the pyrolysis, and so the difficulties, encountered during the experiments are detailed. The optimum operation of the gasifier is found to be between 1.44 and 1.47 N m{sup 3}/kg of air fuel ratios at the values of 4.06 and 4.48 kg/h of wet feed rate which produces the producer gas with a good GCV of about 5 MJ/m{sup 3} at a volumetric flow of 8-9 N m{sup 3}/h product gas. It was concluded that hazelnut shells could be easily gasified in a downdraft gasifier to produce good quality gas with minimum polluting by-products. It is suggested that, in view of ease of operation, small

  12. 含硫生物质气化气催化燃烧性能研究%Catalytic Combustion of Sulphur-Bearing Gasified Biomass

    Institute of Scientific and Technical Information of China (English)

    彭丹; 孙路石; 王志远; 向军; 胡松; 苏胜; 王鹏恒

    2012-01-01

    Precious metal based catalyst Pd/LaAl11O19 and Pt/LaA111019 were prepared and characterized by means of XRD and BET. Then washcoated on cordierite monoliths and tested in a bench scale reactor with a synthetic low-heating value fuel that resembles the gas from gasification of biomass, besides 0.005% hydrogen sulphide were added to the fuel to investigate the influence of sulphur on the catalytic combustion. Combined the characterization results of XPS, SEM and FTIR after the activity tests, a preliminary analysis of the mechanism for the sulfur poisoning of the catalysts were deduced. The results show excellent catalytic activity for the catalysts which significantly reducing the ignition temperature of combustible ingredients, the low temperature activity for Pd was superior to Pt. Besides all samples were deactivated to some extent by addition of sulphur, although poisoning effect varied depending on the active phase. The poisoning processes mainly through the formation of sulfate which deposition on the surface composition, then covered the active site resulting a decrease in catalytic activity.%制备了Pt和Pd负载LaAl11O19整体式催化剂,借助XRD和BET对其进行了表征,同时考察了催化剂作用下模拟生物质气化气的燃烧特性及气化气中加入H2S对可燃成分催化燃烧的影响。结合失活样的XPS、SEM和FTIR表征结果,初步分析催化剂硫中毒的机理。结果表明,制得催化剂活性优良,明显降低了可燃成分的起燃温度,低温下Pd的活性优于Pt,Pd和Pt在抗硫中毒性上是不同的,催化剂失活是通过生成的表面硫酸盐覆盖活性位,失活后有一定的再生性。

  13. 生物质气化火灾爆炸事故复合型风险评价%Integrated Risk Assessment of Biomass Gasified Fire and Explosion Accidents

    Institute of Scientific and Technical Information of China (English)

    闫放; 许开立; 姚锡文; 王犇

    2015-01-01

    为降低生物质气化火灾爆炸事故发生的概率,提出了一种将贝叶斯网络与 boW-tie 法相结合的风险评价方法。通过建立火灾爆炸事故的故障树并转化成贝叶斯网络,然后计算各基本事件的重要度,进而找出系统中导致事故发生的薄弱环节。采用 boW-tie 对薄弱环节进行分析,提出相应的预防措施与控制措施,并计算了薄弱环节采取控制措施后事故发生概率降低的幅度。该方法可精确找出导致事故发生的最主要原因及有效预防控制措施,达到有效降低生物质气化火灾爆炸事故发生概率的目的。%In order to reduce the occurrence of fire and explosion accidents ,a risk assessment approach integrating Bayesian netWork and boW-tie analysis Was proposed.Firstly,the fault tree is established and transformed into Bayesian netWork.Then the Weak points Which might lead to accidents can be pinpointed by calculating the importance of each basic event.The boW-tie analysis is given on the Weak points to Work out the precautions and control measures,and the reduction of accident frequency is calculated after taking control measures for the Weak points. The reasons for such accidents can be found accurately by this approach,Which helps to take appropriate precautions and control measures so as to effectively reduce the occurrence of biomass gasified fire and explosion accidents.

  14. Production of methanol/DME from biomass

    DEFF Research Database (Denmark)

    Ahrenfeldt, Jesper; Henriksen, Ulrik Birk; Münster-Swendsen, Janus;

    In this project the production of DME/methanol from biomass has been investigated. Production of DME/methanol from biomass requires the use of a gasifier to transform the solid fuel to a synthesis gas (syngas) - this syngas can then be catalytically converted to DME/methanol. Two different gasifi...

  15. Bed agglomeration in biomass fueled CFB-boilers; Sintring av baeddmaterial vid biobraensleeldning i CFB

    Energy Technology Data Exchange (ETDEWEB)

    Zintl, F. [TPS Termiska Processer AB, Nykoeping (Sweden)

    1997-02-01

    In fluidized-bed boilers fired with solid fuels operational problems caused by spontaneous defluidization are sometimes observed. This bed agglomeration can be caused by sintering phenomena where fuel components and/or bed material may be involved. In serious cases the problems can lead to expensive operation breaks. The objective in this project was to show whether this type of operational problems can be minimized by choice of other than conventional bed materials. The study was carried out as model experiments in a larger laboratory scale. In a fluidized bed fired with propane a number of both well known and more unusual bed materials were tried out. The choice of bed materials included some common sands (silver and quartz sand) and, as possible alternatives, olivine sand, zirconium sand, calcined dolomite and the synthetic materials sintered magnesite (MgO) and mullite (alumina silicate). The model experiments were started at about 700 deg C and the temperature then raised until an irreversible bed agglomeration was observed, or to a maximum of 1100 deg C. The most promising results were obtained with calcined dolomite, being an active bed material. With this material no irreversible agglomerations were observed at all. The expensive synthetic materials sintered magnesite and mullite and the zirconium sand turned out as the next best. Olivine sand, on the other hand, showed a clear sensitivity to physical agglomeration and some sensitivity also towards sintering. The common sand types based on silicon oxide clearly showed the worst results. 12 refs, 5 figs, 1 tab 12 refs, 5 figs, 1 tab

  16. Modeling work of a small scale gasifier/SOFC CHP system

    Energy Technology Data Exchange (ETDEWEB)

    Liu, M.; Aravind, P.V.; Qu, Z.; Woudstra, N.; Verkooijen, A.H.M. [Delft University of Technology (Netherlands). Dept. of Mechanical Engineering], Emails: ming.liu@tudelft.nl, p.v.aravind@tudelft.nl, z.qu@tudelft.nl, n.woudstra@tudelft.nl, a. h. m. verkooijen@tudelft.nl; Cobas, V.R.M. [Federal University of Itajuba (UNIFEI), Pinheirinhos, MG (Brazil). Dept. of Mechanical Engineering], E-mail: vlad@unifei.edu.br

    2009-07-01

    For a highly efficient biomass gasification/Solid Oxide Fuel Cell (SOFC) Combined Heat and Power (CHP) generation system, the gasifier, the accompanying gas cleaning technologies and the CHP unit must be carefully designed as an integrated unit. This paper describes such a system involving a two-stage fixed-bed down draft gasifier, a SOFC CHP unit and a gas cleaning system. A gas cleaning system with both low temperature and high temperature sections is proposed for coupling the gasifier and the SOFC. Thermodynamic modeling was carried out for the gasifier/SOFC system with the proposed gas cleaning system. The net AC electrical efficiency of this system is around 30% and the overall system efficiency is around 60%. This paper also describes various exergy losses in the system and the future plans for integrated gasifier-GCU-SOFC experiments from which the results will be used to validate the modeling results of this system. (author)

  17. Dicty_cDB: CFB689 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFB689 (Link to dictyBase) - - - Contig-U14176-1 CFB689E (Link to Original ... scsiy trirv*fnttifsttti**sqw*tttttttic*sttrrhck*rt*car **kk*nlcccin ycsrl*cwtrrch*stss**rtydfikt*sws*scqsk ...

  18. Dicty_cDB: CFB766 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CF (Link to library) CFB766 (Link to dictyBase) - - - Contig-U16243-1 CFB766P (Link to Original ... .. 223 e-101 X75329_1( X75329 |pid:none) M.indica (Manila ) THMF5 mRNA for 3-ket... 222 e-101 S57792( S57792 ...

  19. COAL COMBUSTION EFFICIENCY IN CFB BOILER

    Institute of Scientific and Technical Information of China (English)

    Hairui Yang; Guangxi Yue

    2005-01-01

    The carbon content in the fly ash from most Chinese circulating fluidized bed (CFB) boilers is much higher than expected, thus directly influencing the combustion efficiency. In the present paper, carbon burnout was investigated both in field tests and laboratory experiments. The effect of coal property, operation condition, gas-solid mixing, char deactivation,residence time and cyclone performance are analyzed seriatim based on large amount of experimental results.A coal index is proposed to describe the coal rank, defined by the ratio of the volatile content to the coal heat value, is a useful parameter to analyze the char burnout. The carbon content in the fly ash depends on the coal rank strongly. CFB boilers burning anthracite, which has low coal index, usually have high carbon content in the fly ash. On the contrary, the CFB boilers burning brown coal, which has high coal index, normally have low carbon content.Poor gas-solid mixing in the furnace is another important reason of the higher carbon content in the fly ash. Increasing the velocity and rigidity of the secondary air could extend the penetration depth and induce more oxygen into the furnace center. Better gas solid mixing will decrease the lean oxygen core area and increase char combustion efficiency.The fine char particles could be divided into two groups according to their reactivity. One group is "fresh" char particles with high reactivity and certain amount of volatile content. The other group of char particles has experienced sufficient combustion time both in the furnace and in the cyclone, with nearly no volatile. These "old" chars in the fly ash will be deactivated during combustion of large coal particles and have very low carbon reactivity. The generated fine inert char particles by attrition of large coal particles could not easily burn out even with the fly ash recirculation. The fraction of large coal particles in coal feed should be reduced during fuel preparation process.The cyclone

  20. PNNL Coal Gasifier Transportation Logistics

    Energy Technology Data Exchange (ETDEWEB)

    Reid, Douglas J.; Guzman, Anthony D.

    2011-04-13

    This report provides Pacific Northwest National laboratory (PNNL) craftspeople with the necessary information and suggested configurations to transport PNNL’s coal gasifier from its current location at the InEnTec facility in Richland, Washington, to PNNL’s Laboratory Support Warehouse (LSW) for short-term storage. A method of securing the gasifier equipment is provided that complies with the tie-down requirements of the Federal Motor Carrier Safety Administration’s Cargo Securement Rules.

  1. Economical Comporison PC and CFB Boilers for Retrofit and New Power Plants in Russia

    Science.gov (United States)

    Ryabov, G. A.

    According to the investment programmes of Russian electricity generating companies increased attention is paid to reconstruction and building new coal TPP. The typical projects are 225, 330 and 600 MW blocks for combustion of different domestic coals. VTI had made technical and economical comparison of CFB and PC boilers for existing and perspective (European) standards of particles, NOx and SOx emissions, according to the data of the prehminary designs and investments in new power plants of 225 and 330 MW. As the basis for technical and economical evaluations was used comparison data of metal-capacity of PC and boilers, emissions-control systems and material-handling systems, with paying attention to the exact suggestions of the boiler producers. The results of the comparisons (capital costs and O&M costs) are discussed in the paper. The most perspective fuels for combustion in CFB boilers are: anthracite culm, coals of the Pechora area, lean coals of Kuznetsk, brown coals of near Moscow, brown coals of Urals and Far East, and also the wastes of coal preparations, peat, shells and biomass. A good composition could be made from Kuznetsk coals and coals of Pechora area. Brown coals are combusted very good in suitable conditions for firing biomass and peat. Also allowed co-combustion with the wastes of coal preparations for the low reactivity fuels such as anthracite culm and lean coals. The diversification of the fuel supply is an essential advantage of CFB boilers. The CFB boiler installations are rather new for the conditions of Russian Federation. For decreasing the technical risks, first installations should be supplied by engineering or license of leading foreign companies with rather big part of their participation. One of important tasks is development of the typical projects, which would allow decreasing not only capital costs, but also decrease time of project realization. The project of the new Block #9 330MW with OTU boiler of Novocherkassk TPP is the

  2. Gasification of ‘Loose’ Groundnut Shells in a Throathless Downdraft Gasifier

    Directory of Open Access Journals (Sweden)

    Aondoyila Kuhe

    2015-07-01

    Full Text Available In this paper, gasification potential of biomass residue was investigated using a laboratory scale throatless downdraft gasifier. Experimental results of groundnut shell was gasified in the throatless downdraft gasifier to produce a clean gas with a calorific value of around 5.92 MJ/Nm3 and a combustible fraction of 45% v/v. Low moisture (8.6% and ash content (3.19% are the main advantages of groundnut shells for gasification. It is suggested that gasification of shell waste products is a clean energy alternative to fossil fuels. The product gas can be used efficiently for heating and possible usage in internal combustion engines.

  3. Morgantown low-Btu gasifier simulation program

    Energy Technology Data Exchange (ETDEWEB)

    1978-10-01

    This project's overall purpose is to develop a Morgantown low-Btu gasifier system simulation program. The gasifier system consists of a moving bed gasifier and a gas clean-up system, and the present report concerns steady-state simulation of the gasifier. Since the gasifier output controls the performance of the gas clean-up system, it is necessary to investigate the effects of steam/coal and oxygen/coal ratios and of feed temperature on the gasifier output. Simulation of the gasifier performance, therefore, was undertaken to gain quantitative understanding of these effects. This gasifier simulation program will be coupled with a gas clean-up system simulation program now under development. Simulation of the entire gasifier system will serve as a guideline in planning experiments to enable its optimum overall operation.

  4. Aviary heating: control of air temperature heated by a set biomass gasifier-combustor in a co-current flow, using a frequency inverter; Aquecimento de aviarios: controle da temperatura do ar aquecido por um conjunto gaseificador-combustor de biomassa de fluxo concorrente, utilizando um inversor de frequencia

    Energy Technology Data Exchange (ETDEWEB)

    Santos, William Rosario dos [Universidade Presidente Antonio Carlos (UNIPAC), Ponte Nova, MG (Brazil); Silva, Jadir Nogueira; Oliveira Filho, Delly; Martins, Marcio Aredes; Oliveira, Jofran Luiz de [Universidade Federal de Vicosa (UFV), MG (Brazil)], Emails: jadir@ufv.br, delly@ufv.br, aredes@ufv.br, jofran.oliveira@ufv.br

    2009-07-01

    One of the problems with using the gasifier for heating purposes in poultry facilities is the waste of energy during the day, once the equipment does not have control of the thermal and power generated. During this period, the difference in temperature between the air and the standard for the birds inside the building is lower than when compared with the nocturnal period. During the day, the temperature inside the poultry house is controlled by curtains, which occurs without diminishing the biomass burning. Another way to control the temperature is the shutdown of the system, which requires the constant attention of the operator. In this way, there is a potential for energy savings if the thermal power could be controlled according to the demand, which can be represented by the temperature gradient. The purpose of this study was to control the temperature of exhaustion air from a set combustor-gasifier (down draft), based on the model developed by Martin et al. (2006), through the control of speed of the fan engine and also controlling the flow contributions of primary and secondary air in the combustor. The experiment was carried out in the Energy and Pre-processing of Agricultural Products areas, at the Department of Agricultural Engineering - Federal University of Vicosa. (author)

  5. Photoconversion of gasified organic materials into biologically-degradable plastics

    Science.gov (United States)

    Weaver, Paul F.; Maness, Pin-Ching

    1993-01-01

    A process is described for converting organic materials (such as biomass wastes) into a bioplastic suitable for use as a biodegradable plastic. In a preferred embodiment the process involves thermally gasifying the organic material into primarily carbon monoxide and hydrogen, followed by photosynthetic bacterial assimilation of the gases into cell material. The process is ideally suited for waste recycling and for production of useful biodegradable plastic polymer.

  6. Particle Distribution in a Fixed Bed Down Draft Wood Gasifier

    DEFF Research Database (Denmark)

    Hindsgaul, Claus

    2005-01-01

    Char particle samples were collected from six distances above the grate in a fixed bed of a down draft biomass gasifier. Each sample was separated into twelve size fractions by screening through standard sieves in order to determine the local particle size distribution. The ash contents of each...... particle fraction was determined. The measured ash content in the larger particles was nearly constant throughout the bed, while ash accumulated in particle sizes around 1 mm near the bottom....

  7. Refractory for Black Liquor Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Laing

    2005-10-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  8. CHP from Updraft Gasifier and Stirling Engine

    DEFF Research Database (Denmark)

    Jensen, N.; Werling, J.; Carlsen, Henrik;

    2002-01-01

    The combination of thermal gasification with a Stirling engine is an interesting concept for use in small combined heat and power plants based on biomass. By combining the two technologies a synergism can potentially be achieved. Technical problems, e.g. gas cleaning and fouling of the Stirling...... engine heat exchanger, can be eliminated and the overall electric efficiency of the system can be improved. At the Technical University of Denmark a Stirling engine fueled by gasification gas has been developed. In this engine the combustion system and the geometry of the hot heat exchanger...... of the Stirling engine has been adapted to the use of a gas with a low specific energy content and a high content of tar and particles. In the spring of 2001 a demonstration plant has been built in the western part of Denmark where this Stirling engine is combined with an updraft gasifier. A mathematical...

  9. Extending EMMS-based models to CFB boiler applications

    Institute of Scientific and Technical Information of China (English)

    Bona Lu; Nan Zhang; Wei Wang; Jinghai Li

    2012-01-01

    Recently,EMMS-based models are being widely applied in simulations of high-throughput circulating fluidized beds (CFBs) with fine particles.Its use for low flux systems,such as CFB boiler (CFBB),still remains unexplored.In this work,it has been found that the original definition of cluster diameter in EMMS model is unsuitable for simulations of the CFB boiler with low solids flux.To remedy this,we propose a new model of cluster diameter.The EMMS-based drag model (EMMS/matrix model) with this revised cluster definition is validated through the computational fluid dynamics (CFD) simulation of a CFB boiler.

  10. Energetic, ecologic and fluid-dynamic analysis of a fluidized bed gasifier operating with sugar cane bagasse

    International Nuclear Information System (INIS)

    This work aims to study the thermodynamic, ecological and fluid-dynamic aspects of a circulating fluidized bed gasifier using sugar cane bagasse as biomass, in order to estimate a model of its normal operation. In the initial stage was analysed the composition of biomass selected (sugar cane bagasse) and its lower heating value (LHV) was calculated. The energy balance of the gasifier was done, being the volumetric flow of air, synthesis gas and biomass estimated. Also the power produced by this gasifier was theoretically estimated. Then the circulating fluidized bed gasifier was designed for operation with approximately 100 kg/h of processed biomass. Cross-sectional area of the reactor, feeder size, diameter of the exit zone of the gases and minimum height of the expanded bed were selected. Some bed gasifier hydrodynamic factors were also studied. The minimum fluidization velocity, fluidization terminal velocity, and average fluidizing velocity were calculated, in order to understand the fluid-dynamic behaviour of gasification of this fuel. It was obtained a theoretical model that can support a possible prototype of circulating fluidized bed gasifier biomass. Finally, there were studied the ecological aspects of the gasifier, through an overall methodology. Ecological efficiencies were estimated for two scenarios: first considering the carbon cycle and thereafter disregarding the carbon cycle. In both cases, it can be proved the ecological viability of the project. -- Highlights: • we develop a methodology to size a fluidized bed gasifier. • we validate this methodology comparing to a fixed bed gasifier values. • we aggregate ecological efficiency to this methodology

  11. Development and Validation of a 3-Dimensional CFB Furnace Model

    Science.gov (United States)

    Vepsäläinen, Arl; Myöhänen, Karl; Hyppäneni, Timo; Leino, Timo; Tourunen, Antti

    At Foster Wheeler, a three-dimensional CFB furnace model is essential part of knowledge development of CFB furnace process regarding solid mixing, combustion, emission formation and heat transfer. Results of laboratory and pilot scale phenomenon research are utilized in development of sub-models. Analyses of field-test results in industrial-scale CFB boilers including furnace profile measurements are simultaneously carried out with development of 3-dimensional process modeling, which provides a chain of knowledge that is utilized as feedback for phenomenon research. Knowledge gathered by model validation studies and up-to-date parameter databases are utilized in performance prediction and design development of CFB boiler furnaces. This paper reports recent development steps related to modeling of combustion and formation of char and volatiles of various fuel types in CFB conditions. Also a new model for predicting the formation of nitrogen oxides is presented. Validation of mixing and combustion parameters for solids and gases are based on test balances at several large-scale CFB boilers combusting coal, peat and bio-fuels. Field-tests including lateral and vertical furnace profile measurements and characterization of solid materials provides a window for characterization of fuel specific mixing and combustion behavior in CFB furnace at different loads and operation conditions. Measured horizontal gas profiles are projection of balance between fuel mixing and reactions at lower part of furnace and are used together with both lateral temperature profiles at bed and upper parts of furnace for determination of solid mixing and combustion model parameters. Modeling of char and volatile based formation of NO profiles is followed by analysis of oxidizing and reducing regions formed due lower furnace design and mixing characteristics of fuel and combustion airs effecting to formation ofNO furnace profile by reduction and volatile-nitrogen reactions. This paper presents

  12. A Philippines gasifier case study

    International Nuclear Information System (INIS)

    The gasifier programme failed to achieve its objective of significantly reducing farmers' dependence on diesel fuel and in improving their financial positions both on Panay Island and elsewhere in the Philippines. The causes appear to be institutional and managerial rather than any inherent weakness in the technology itself. 2 tabs

  13. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Jun Wei

    2005-03-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  14. Bolivia: A Gasified Democracy

    Directory of Open Access Journals (Sweden)

    Willem Assies

    2004-04-01

    Full Text Available In October 2003 a wave of popular protest  brought down the Sánchez de Lozada government  in Bolivia. The intention to export natural gas to  the United States and Mexico triggered the protests, but actually stood for widespread discontent  with the Sánchez de Lozada government, the  preceding governments and the economic policies  pursued since 1985. The events belie the opinion  of various students of the Latin American democratic transitions who held that Bolivian democracy  was on its way towards consolidation and suggest that the recent inquiries into the quality of Latin  American democracies may point a way ahead in  rethinking democracy in the region. Taking such  assessments as a reference, this article reviews the  ‘gas war’ and looks at the Bolivian political regime as it has functioned over the past decades. It  will be argued that the ‘pacted democracy’, that  until now sustained institutionality, and the economic model adopted in 1985 have excluded an  important part of the population, both in political terms and where poverty alleviation and equity is  concerned. Increasing popular protest has been  met with increasing repression, which gradually  turned Bolivia into a ‘democradura’, or a ‘gasified  democracy’ that relies on teargas and bullets to  uphold itself. At present the country finds itself at  a crossroads. It either may reinvent democracy or  become an institutionalized ‘democradura’. Resumen: Bolivia: una democracia gasificadaEn octubre de 2003 una ola de protesta popular  llevó a la caída del gobierno de Sánchez de Lozada en Bolivia. La intención de exportar gas natural a los Estados Unidos y México gatilló dichas  protestas, aunque en realidad reflejaron un descontento general con el gobierno Sánchez de  Lozada, los gobiernos anteriores y las políticas  económicas implementadas desde 1985. Los  sucesos desmienten la opinión de varios analistas  de las

  15. Characterization of Rice Husk for Cyclone Gasifier

    Science.gov (United States)

    Mohamad Yusof, I.; Farid, N. A.; Zainal, Z. A.; Azman, M.

    The characterization of rice husk from local rice mills has been studied and evaluated to determine its potential utilization as a biomass fuel for a cyclone gasifier. The raw rice husk was pre-treated throughout a grinding process into smaller sizes of particles which is within a range of 0.4 to 1 mm and the sample of ground rice husk was analyzed for its fuel characteristics. The result of proximate analysis shows that the ground rice husk with size distribution within 0.4 to 1 mm contains 13.4% of fixed carbon, 62.95% of volatile matter and 18.5% of ash on dry basis. The moisture content of the sample was measured and determined as 10.4% (wet basis) and the calorific value was found to be approximately 14.8 MJ kg-1 with bulk density of 91.46 kg m-3. The result of ultimate analysis validates both ash and moisture content which are found to be 18.15 and 10.4%, respectively. Other elemental compositions determined by the ultimate analysis are carbon (37.9%), hydrogen (5.2%), nitrogen (0.14%), sulfur (0.61%) and oxygen (27.7% by difference). The study has identified that the fuel characteristics of the ground rice husk is comparable with other types of biomass and thus, making it another potential source of fuel for the cyclone gasification system.

  16. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr.; Alireza Rezaie

    2004-04-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the materials problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  17. Refractory for Black Liquor Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Alireza Rezaie; Xiaoting Liang; Musa Karakus; Jun Wei

    2005-12-01

    The University of Missouri-Rolla identified materials that permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project was to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study attempted to define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials were selected or developed that reacted with the gasifier environment to form protective surfaces in

  18. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang; Alireza Rezaie

    2004-07-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  19. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang

    2005-07-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  20. Refractory for Black Liquor Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang

    2005-10-01

    The University of Missouri-Rolla identified materials that permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project was to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study attempted to define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials were selected/developed that either react with the gasifier environment to form protective surfaces in

  1. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang; Jun Wei

    2005-01-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  2. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang; Alireza Rezaie

    2004-10-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  3. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang; Jun Wei

    2005-04-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  4. Refractory for Black Liquor Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick; Musa Karakus; Alireza Rezaie

    2004-03-30

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

  5. Dynamic Testing of Gasifier Refractory

    Energy Technology Data Exchange (ETDEWEB)

    Michael D. Mann; Wayne S. Seames; Devdutt Shukla; Xi Hong; John P. Hurley

    2005-12-01

    The University of North Dakota (UND) Chemical Engineering Department in conjunction with the UND Energy & Environmental Research Center (EERC) have initiated a program to examine the combined chemical (reaction and phase change) and physical (erosion) effects experienced by refractory materials under slagging coal gasification conditions. The goal of this work is to devise a mechanism of refractory loss under these conditions. The controlled-atmospheric dynamic corrodent application furnace (CADCAF) was utilized to simulate refractory/slag interactions under dynamic conditions that more realistically simulate the environment in a slagging coal gasifier than any of the static tests used previously by refractory manufacturers and researchers. High-alumina and high-chromia refractory bricks were tested using slags obtained from two solid fuel gasifiers. Testing was performed at 1475 C in a reducing atmosphere (2% H{sub 2} in N{sub 2}) The CADCAF tests show that high-chrome refractories have greater corrosion resistance than high-aluminum refractories; coal slag readily diffuses into the refractory through its grain boundaries; the refractory grains are more stable than the matrix in the tests, and the grains are the first line of defense against corrosion; calcium and alkali in the slag are more corrosive than iron; and silicon and calcium penetrate the deepest into the refractory. The results obtained from this study are preliminary and should be combined with result from other research programs. In particular, the refractory corrosion results from this study should be compared with refractories removed from commercial gasifiers.

  6. Advanced Gasifier Pilot Plant Concept Definition

    Energy Technology Data Exchange (ETDEWEB)

    Steve Fusselman; Alan Darby; Fred Widman

    2005-08-31

    This report presents results from definition of a preferred commercial-scale advanced gasifier configuration and concept definition for a gasification pilot plant incorporating those preferred technologies. The preferred commercial gasifier configuration was established based on Cost Of Electricity estimates for an IGCC. Based on the gasifier configuration trade study results, a compact plug flow gasifier, with a dry solids pump, rapid-mix injector, CMC liner insert and partial quench system was selected as the preferred configuration. Preliminary systems analysis results indicate that this configuration could provide cost of product savings for electricity and hydrogen ranging from 15%-20% relative to existing gasifier technologies. This cost of product improvement draws upon the efficiency of the dry feed, rapid mix injector technology, low capital cost compact gasifier, and >99% gasifier availability due to long life injector and gasifier liner, with short replacement time. A pilot plant concept incorporating the technologies associated with the preferred configuration was defined, along with cost and schedule estimates for design, installation, and test operations. It was estimated that a 16,300 kg/day (18 TPD) pilot plant gasifier incorporating the advanced gasification technology and demonstrating 1,000 hours of hot-fire operation could be accomplished over a period of 33 months with a budget of $25.6 M.

  7. Ultra-Supercritical Pressure CFB Boiler Conceptual Design Study

    Energy Technology Data Exchange (ETDEWEB)

    Zhen Fan; Steve Goidich; Archie Robertson; Song Wu

    2006-06-30

    Electric utility interest in supercritical pressure steam cycles has revived in the United States after waning in the 1980s. Since supercritical cycles yield higher plant efficiencies than subcritical plants along with a proportional reduction in traditional stack gas pollutants and CO{sub 2} release rates, the interest is to pursue even more advanced steam conditions. The advantages of supercritical (SC) and ultra supercritical (USC) pressure steam conditions have been demonstrated in the high gas temperature, high heat flux environment of large pulverized coal-fired (PC) boilers. Interest in circulating fluidized bed (CFB) combustion, as an alternative to PC combustion, has been steadily increasing. Although CFB boilers as large as 300 MWe are now in operation, they are drum type, subcritical pressure units. With their sizes being much smaller than and their combustion temperatures much lower than those of PC boilers (300 MWe versus 1,000 MWe and 1600 F versus 3500 F), a conceptual design study was conducted herein to investigate the technical feasibility and economics of USC CFB boilers. The conceptual study was conducted at 400 MWe and 800 MWe nominal plant sizes with high sulfur Illinois No. 6 coal used as the fuel. The USC CFB plants had higher heating value efficiencies of 40.6 and 41.3 percent respectively and their CFB boilers, which reflect conventional design practices, can be built without the need for an R&D effort. Assuming construction at a generic Ohio River Valley site with union labor, total plant costs in January 2006 dollars were estimated to be $1,551/kW and $1,244/kW with costs of electricity of $52.21/MWhr and $44.08/MWhr, respectively. Based on the above, this study has shown that large USC CFB boilers are feasible and that they can operate with performance and costs that are competitive with comparable USC PC boilers.

  8. Seward CFB boilers will curb water pollution and air emissions

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-03-01

    When Reliant Energy Co's Seward station begins commercial operation in 2004, it will replace an 80-yr-old pulverized-coal plant with a circulating fluidized bed (CFB) facility that more than doubles the capacity while slashing total air emissions. The baseload facility, located in Indiana County, PA, will be fuelled by local low-grade waste coal. Added to the back end of the two 292-MW CFB boilers, selective noncatalytic reduction equipment will lower NOx emissions, and ALSTOM's flash dryer absorber (FDA) system will lower SO{sub 2} emissions whilst using less limestone. 3 photos.

  9. Comparison of ORC Turbine and Stirling Engine to Produce Electricity from Gasified Poultry Waste

    OpenAIRE

    Franco Cotana; Antonio Messineo; Alessandro Petrozzi; Valentina Coccia; Gianluca Cavalaglio; Andrea Aquino

    2014-01-01

    The Biomass Research Centre, section of CIRIAF, has recently developed a biomass boiler (300 kW thermal powered), fed by the poultry manure collected in a nearby livestock. All the thermal requirements of the livestock will be covered by the heat produced by gas combustion in the gasifier boiler. Within the activities carried out by the research project ENERPOLL (Energy Valorization of Poultry Manure in a Thermal Power Plant), funded by the Italian Ministry of Agriculture and Forestry, this p...

  10. Preliminary tests with a birch wood pellets up-draft air gasifier

    OpenAIRE

    Grimm, Alejandro; Suarez, José; Björnbom, Emilia; Zanzi Vigouroux, Rolando

    2004-01-01

    In Sweden and Cuba a variety of biomass have being investigated for energyconversion through termochemical processes into solid, liquids and gaseous products. Biomass gasification in fixed bed seem to be attractive option for the conversion ofagricultural and forest residues into gases suitable for use as alternative fuel in gasengines in rural areas, heat or electricity production. This paper discusses the performance characteristics of a up - draft gasifier withBirch wood pellets. The bench...

  11. 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

  12. Biomass Wet Firewood Experimental Study of the Direct-Fired Gasifier Performance%生物质湿柴直燃气化炉性能的试验研究

    Institute of Scientific and Technical Information of China (English)

    张巍; 王维新; 马飞

    2013-01-01

    为了研究生物质湿柴直燃气化炉在燃烧时秸秆的各个参数对其加热效率的影响规律,以热效率为评价指标,对棉花秸秆长度,棉花秸秆数量以及棉花秸秆含水率等试验因素进行中心组合试验,对结果进行了方差分析,研究各因素对湿柴炉加热效率影响的主次关系,确定较优参数组合.结果表明,棉花秸秆长度38.20 em、棉花秸秆数量67根、含水率15.40%时为较优参数组合.其热效率可达30.20%以上.%In order to graduate substance wet firewood direct-fired gasifier burning straw various parameters investigated its heating efficiency, thermal efficiency evaluation index, orthogonal experiment experimental factors of length of cotton stalks, cotton stalks, cotton stalks moistureand. Analysis of variance results, the study of various factors on the relationship between the primary and secondary the wet wood stove heating efficiency impact, determine the optimum parameters combination. The results show that: length 38.20cm, 15.40% of the cotton stalks the number of 67, the moisture content of cotton stalks as a combination of the optimum parameters, the thermal efficiency of up to 30.20%.

  13. Production of methanol/DME from biomass

    Energy Technology Data Exchange (ETDEWEB)

    Ahrenfeldt, J.; Birk Henriksen, U.; Muenster-Swendsen, J.; Fink, A.; Roengaard Clausen, L.; Munkholt Christensen, J.; Qin, K.; Lin, W.; Arendt Jensen, P.; Degn Jensen, A.

    2011-07-01

    In this project the production of DME/methanol from biomass has been investigated. Production of DME/methanol from biomass requires the use of a gasifier to transform the solid fuel to a synthesis gas (syngas) - this syngas can then be catalytically converted to DME/methanol. Two different gasifier types have been investigated in this project: 1) The Two-Stage Gasifier (Viking Gasifier), designed to produce a very clean gas to be used in a gas engine, has been connected to a lab-scale methanol plant, to prove that the gas from the gasifier could be used for methanol production with a minimum of gas cleaning. This was proved by experiments. Thermodynamic computer models of DME and methanol plants based on using the Two-Stage Gasification concept were created to show the potential of such plants. The models showed that the potential biomass to DME/methanol + net electricity energy efficiency was 51-58% (LHV). By using waste heat from the plants for district heating, the total energy efficiencies could reach 87-88% (LHV). 2) A lab-scale electrically heated entrained flow gasifier has been used to gasify wood and straw. Entrained flow gasifiers are today the preferred gasifier type for commercial coal gasification, but little information exists on using these types of gasifiers for biomass gasification. The experiments performed provided quantitative data on product and gas composition as a function of operation conditions. Biomass can be gasified with less oxygen consumption compared to coal. The organic fraction of the biomass that is not converted to gas appears as soot. Thermodynamic computer models of DME and methanol plants based on using entrained flow gasification were created to show the potential of such plants. These models showed that the potential torrefied biomass to DME/methanol + net electricity energy efficiency was 65-71% (LHV). Different routes to produce liquid transport fuels from biomass are possible. They include production of RME (rapeseed oil

  14. Catalytic Combustion of Gasified Waste

    Energy Technology Data Exchange (ETDEWEB)

    Kusar, Henrik

    2003-09-01

    This thesis concerns catalytic combustion for gas turbine application using a low heating-value (LHV) gas, derived from gasified waste. The main research in catalytic combustion focuses on methane as fuel, but an increasing interest is directed towards catalytic combustion of LHV fuels. This thesis shows that it is possible to catalytically combust a LHV gas and to oxidize fuel-bound nitrogen (NH{sub 3}) directly into N{sub 2} without forming NO{sub x} The first part of the thesis gives a background to the system. It defines waste, shortly describes gasification and more thoroughly catalytic combustion. The second part of the present thesis, paper I, concerns the development and testing of potential catalysts for catalytic combustion of LHV gases. The objective of this work was to investigate the possibility to use a stable metal oxide instead of noble metals as ignition catalyst and at the same time reduce the formation of NO{sub x} In paper II pilot-scale tests were carried out to prove the potential of catalytic combustion using real gasified waste and to compare with the results obtained in laboratory scale using a synthetic gas simulating gasified waste. In paper III, selective catalytic oxidation for decreasing the NO{sub x} formation from fuel-bound nitrogen was examined using two different approaches: fuel-lean and fuel-rich conditions. Finally, the last part of the thesis deals with deactivation of catalysts. The various deactivation processes which may affect high-temperature catalytic combustion are reviewed in paper IV. In paper V the poisoning effect of low amounts of sulfur was studied; various metal oxides as well as supported palladium and platinum catalysts were used as catalysts for combustion of a synthetic gas. In conclusion, with the results obtained in this thesis it would be possible to compose a working catalytic system for gas turbine application using a LHV gas.

  15. CANMET Gasifier Liner Coupon Material Test Report

    Energy Technology Data Exchange (ETDEWEB)

    Mark Fitzsimmons; Dave Grimmett; Bryan McEnerney

    2007-01-31

    This report provides detailed test results consisting of test data and post-test inspections from Task 1 ''Cooled Liner Coupon Development and Test'' of the project titled ''Development of Technologies and Capabilities for Coal Energy Resources--Advanced Gasification Systems Development (AGSD)''. The primary objective of this development and test program is to verify that ceramic matrix composite (CMC) liner materials planned for use in an advanced gasifier pilot plant will successfully withstand the environments in a commercial gasifier. Pratt & Whitney Rocketdyne (PWR) designed and fabricated the cooled liner test assembly article that was tested in a slagging gasifier at CANMET Energy Technology Center (CETC-O) in Ottawa, Ontario, Canada. The test program conducted in 2006 met the objective of operating the cooled liner test article at slagging conditions in a small scale coal gasifier at CETC-O for over the planned 100 hours. The test hardware was exposed to at least 30 high temperature excursions (including start-up and shut-down cycles) during the test program. The results of the testing has provided valuable information on gasifier startup and required cooling controls in steady state operation of future advanced gasifiers using similar liners. The test program also provided a significant amount of information in the areas of CMC materials and processing for improved capability in a gasifier environment and insight into CMC liner fabrication that will be essential for near-term advanced gasifier projects.

  16. Provence 250 MWe unit: the largest CFB boiler in operation

    Energy Technology Data Exchange (ETDEWEB)

    Delot, P.; Roulet, V.; Lucat, P.; Levy, D. [Electricite de France, La Defense (France)

    1997-12-31

    Among the new Clean Coal Technologies, `Circulating Fluidized Bed, is one of the most promising. The interest of this technology has been confirmed by the success of the first large French CFB boiler (E. Huchet 125 MWe), which has already logged more than 30 000 hours of satisfactory operation. Today, the first 250 MWe CFB unit in the world is in operation at Provence Power Station in the south of France. At such a size, the CFB technique has now reached a capacity corresponding to thermal power plants operated by utilities. This new unit, with a `pant leg` design, is also a very important step towards larger sizes, i.e. 400 MWe and bigger. The purpose of the Provence project was to replace the existing pulverised coal boiler unit 4, commissioned in 1967, of the Provence/Gardanne power plant, with a new CFB boiler while reusing most of the existing equipment. The new boiler was ordered from GEC ALSTHOM Stein Industrie by Electricite de France (EDF) on behalf of the SOPROLIF consortium. The 250 MWe Boiler is of the high pressure-reheat type firing local high-sulfur sub-bituminous coal with the possibility of cofiring high viscosity residual oil (with a high sulfur content) up to a 50%-50% energy ratio. This paper describes, besides the construction progress of the plant and technical details of the new boiler and auxiliaries, the main observations made during commissioning. Also presented are some results of a 100% load test and the investigation program defined to give a thorough evaluation of this boiler with a view to the design of large CFB in the future.

  17. Gasification of bio-oil: Effects of equivalence ratio and gasifying agents on product distribution and gasification efficiency.

    Science.gov (United States)

    Zheng, Ji-Lu; Zhu, Ming-Qiang; Wen, Jia-Long; Sun, Run-Cang

    2016-07-01

    Bio-oil derived from fast pyrolysis of rice husk was gasified for producing gas. The effectiveness of equivalence ratio and gasifying agents on the gas composition, ratio of H2/CO, tar amount, low heating value, degree of oxidation and cold gas efficiency of the gas were comprehensively investigated. Under different equivalence ratios and gasifying agents, the gases can be used as synthesis gas for Fischer-Tropsch synthesis, fuel gas for gas turbines in a power plant and reducing gas for ore reduction, respectively. The H2 concentration, CO level and cold gas efficiency of the resulted gas derived from gasification of bio-oil were significantly higher, while tar content was remarkably lower than those derived from gasification of solid biomass using the same equivalent ratio value and gasifying agent. In short, bio-oil gasification is economically feasible for large scale production of fuels and chemicals. PMID:27017126

  18. 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.)

  19. Commercial gasifier for IGCC applications study report

    Energy Technology Data Exchange (ETDEWEB)

    Notestein, J.E.

    1990-06-01

    This was a scoping-level study to identify and characterize the design features of fixed-bed gasifiers appearing most important for a gasifier that was to be (1) potentially commercially attractive, and (2) specifically intended for us in integrated coal gasification/combined-cycle (IGCC) applications. It also performed comparative analyses on the impact or value of these design features and on performance characteristics options of the whole IGCC system since cost, efficiency, environmental traits, and operability -- on a system basis -- are what is really important. The study also reviewed and evaluated existing gasifier designs, produced a conceptual-level gasifier design, and generated a moderately advanced system configuration that was utilized as the reference framework for the comparative analyses. In addition, technical issues and knowledge gaps were defined. 70 figs., 31 tabs.

  20. Two-dimensional coal combustion modeling of CFB

    Energy Technology Data Exchange (ETDEWEB)

    Gungor, Afsin; Eskin, Nurdil [Istanbul Technical University, Mechanical Engineering Faculty, Gumussuyu, 34437, Istanbul (Turkey)

    2008-02-15

    In this study, a dynamic 2D model for a CFB combustor has been developed which integrates and simultaneously predicts the hydrodynamics, heat transfer and combustion aspects. Hydrodynamic model used in this study has been developed in our previous studies. Simulation model calculates the axial and radial distribution of voidage, velocity, particle size distribution, pressure drop, gas emissions and temperature at each time interval for gas and solid phase both for dense bed and for riser. The model has been validated against the data from a pilot-scale 50 kW CFB combustor and an industrial-scale 160 MW CFB combustor. A sensitivity analysis is carried out using the model to examine the effect of different operational parameters and coal properties on bed temperature and the overall CO, NO{sub x} and SO{sub 2} emissions from the combustor. As a result of parametric study, it is observed that by increasing bed operational velocity or excess air ratio, bed temperature decreases and CO emission increases. Bed operational velocity has a more significant effect on CO emission than to bed temperature. Another effect of increasing excess air is the decrease of SO{sub 2} and NO{sub x} emissions. However, NO{sub x} emission increases with the operational bed velocity while SO{sub 2} emission decreases. (author)

  1. Fixed and entrained flow gasifiers - examples

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2009-03-15

    Gasification is a flexible, reliable, and clean energy technology that can turn a variety of low-value feedstocks into high-value products, help reduce our dependence on foreign oil and natural gas, and can provide a clean alternative source of baseload electricity, fertilizers, fuels, and chemicals. According to the Gasification Technologies Council (www.gasification.org) today there are more than 420 gasifiers currently in use in some 140 facilities worldwide. By 2015, worldwide gasification capacity is projected to grow 70%, with 80% of the growth occurring in Asia. The prime movers behind this expected growth are the chemical, fertilizer, and coal-to-liquids industries in China, oil sands in Canada, polygeneration (hydrogen and power or chemicals) and substitute natural gas in the United States, and refining in Europe. Looking far into the future gasification can be a link technology to a hydrogen economy as it produces the hydrogen that will be needed for fuel cells. The heart of a gasification plant is the gasifier. There are several basic designs, distinguished by the use of wet or dry feed, the use of air or oxygen, the reactor's flow direction (up-flow, downflow, or circulating), and the gas cooling process. Hereunder, in addition to Abraham who gives examples of a fluidized and an entrained flow gasifier, the Lurgi fixed bed gasifier as well as the two entrained flow gasifiers from Shell and GE as examples for worldwide utilized gasifiers are shortly described. (orig.)

  2. 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

  3. Comparison of ORC Turbine and Stirling Engine to Produce Electricity from Gasified Poultry Waste

    Directory of Open Access Journals (Sweden)

    Franco Cotana

    2014-08-01

    Full Text Available The Biomass Research Centre, section of CIRIAF, has recently developed a biomass boiler (300 kW thermal powered, fed by the poultry manure collected in a nearby livestock. All the thermal requirements of the livestock will be covered by the heat produced by gas combustion in the gasifier boiler. Within the activities carried out by the research project ENERPOLL (Energy Valorization of Poultry Manure in a Thermal Power Plant, funded by the Italian Ministry of Agriculture and Forestry, this paper aims at studying an upgrade version of the existing thermal plant, investigating and analyzing the possible applications for electricity production recovering the exceeding thermal energy. A comparison of Organic Rankine Cycle turbines and Stirling engines, to produce electricity from gasified poultry waste, is proposed, evaluating technical and economic parameters, considering actual incentives on renewable produced electricity.

  4. Commercialization Development of Oxygen Fired CFB for Greenhouse Gas Control

    Energy Technology Data Exchange (ETDEWEB)

    Nsakala ya Nsakala; Gregory N. Liljedahl; David G. Turek

    2007-03-31

    Given that fossil fuel fired power plants are among the largest and most concentrated producers of CO{sub 2} emissions, recovery and sequestration of CO{sub 2} from the flue gas of such plants has been identified as one of the primary means for reducing anthropogenic (i.e., man-made) CO{sub 2} emissions. In 2001, ALSTOM Power Inc. (ALSTOM) began a two-phase program to investigate the feasibility of various carbon capture technologies. This program was sponsored under a Cooperative Agreement from the US Department of Energy's National Energy Technology Laboratory (DOE). The first phase entailed a comprehensive study evaluating the technical feasibility and economics of alternate CO{sub 2} capture technologies applied to Greenfield US coal-fired electric generation power plants. Thirteen cases, representing various levels of technology development, were evaluated. Seven cases represented coal combustion in CFB type equipment. Four cases represented Integrated Gasification Combined Cycle (IGCC) systems. Two cases represented advanced Chemical Looping Combined Cycle systems. Marion, et al. reported the details of this work in 2003. One of the thirteen cases studied utilized an oxygen-fired circulating fluidized bed (CFB) boiler. In this concept, the fuel is fired with a mixture of oxygen and recirculated flue gas (mainly CO{sub 2}). This combustion process yields a flue gas containing over 80 percent (by volume) CO{sub 2}. This flue gas can be processed relatively easily to enrich the CO{sub 2} content to over 96 percent for use in enhanced oil or gas recovery (EOR or EGR) or simply dried for sequestration. The Phase I study identified the O{sub 2}-fired CFB as having a near term development potential, because it uses conventional commercial CFB technology and commercially available CO{sub 2} capture enabling technologies such as cryogenic air separation and simple rectification or distillation gas processing systems. In the long term, air separation technology

  5. Thermodynamic analysis of small-scale dimethyl ether (DME) and methanol plants based on the efficient two-stage gasifier

    DEFF Research Database (Denmark)

    Clausen, Lasse Røngaard; Elmegaard, Brian; Ahrenfeldt, Jesper;

    2011-01-01

    Models of dimethyl ether (DME) and methanol synthesis plants have been designed by combining the features of the simulation tools DNA and Aspen Plus. The plants produce DME or methanol by catalytic conversion of a syngas generated by gasification of woody biomass. Electricity is co-produced in the...... plants by a gas engine utilizing the unconverted syngas. A two-stage gasifier with a cold gas efficiency of 93% is used, but because of the design of this type of gasifier, the plants have to be of small-scale (5 MWth biomass input). The plant models show energy efficiencies from biomass to DME....../methanol + electricity of 51–58% (LHV), which shows to be 6-8%-points lower than efficiencies achievable on large-scale plants based on torrefied biomass pellets. By using waste heat from the plants for district heating, the total energy efficiencies become 87–88%....

  6. 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...

  7. TASK 3: PILOT PLANT GASIFIER TESTING

    Energy Technology Data Exchange (ETDEWEB)

    Fusselman, Steve

    2015-11-01

    Aerojet Rocketdyne (AR) has developed an innovative gasifier concept incorporating advanced technologies in ultra-dense phase dry feed system, rapid mix injector, and advanced component cooling to significantly improve gasifier performance, life, and cost compared to commercially available state-of-the-art systems. Design, fabrication and initial testing of the pilot plant compact gasifier was completed in 2011 by a development team led by AR. Findings from this initial test program, as well as subsequent gasifier design and pilot plant testing by AR, identified a number of technical aspects to address prior to advancing into a demonstration-scale gasifier design. Key among these were an evaluation of gasifier ability to handle thermal environments with highly reactive coals; ability to handle high ash content, high ash fusion temperature coals with reliable slag discharge; and to develop an understanding of residual properties pertaining to gasification kinetics as carbon conversion approaches 99%. The gasifier did demonstrate the ability to withstand the thermal environments of highly reactive Powder River Basin coal, while achieving high carbon conversion in < 0.15 seconds residence time. Continuous operation with the high ash fusion temperature Xinyuan coal was demonstrated in long duration testing, validating suitability of outlet design as well as downstream slag discharge systems. Surface area and porosity data were obtained for the Xinyuan and Xinjing coals for carbon conversion ranging from 85% to 97%, and showed a pronounced downward trend in surface area per unit mass carbon as conversion increased. Injector faceplate measurements showed no incremental loss of material over the course of these experiments, validating the commercially traceable design approach and supportive of long injector life goals. Hybrid testing of PRB and natural gas was successfully completed over a wide range of natural gas feed content, providing test data to anchor predictions

  8. JV Task 46 - Development and Testing of a Thermally Integrated SOFC-Gasification System for Biomass Power Generation

    Energy Technology Data Exchange (ETDEWEB)

    Phillip Hutton; Nikhil Patel; Kyle Martin; Devinder Singh

    2008-02-01

    The Energy & Environmental Research Center has designed a biomass power system using a solid oxide fuel cell (SOFC) thermally integrated with a downdraft gasifier. In this system, the high-temperature effluent from the SOFC enables the operation of a substoichiometric air downdraft gasifier at an elevated temperature (1000 C). At this temperature, moisture in the biomass acts as an essential carbon-gasifying medium, reducing the equivalence ratio at which the gasifier can operate with complete carbon conversion. Calculations show gross conversion efficiencies up to 45% (higher heating value) for biomass moisture levels up to 40% (wt basis). Experimental work on a bench-scale gasifier demonstrated increased tar cracking within the gasifier and increased energy density of the resultant syngas. A series of experiments on wood chips demonstrated tar output in the range of 9.9 and 234 mg/m{sup 3}. Both button cells and a 100-watt stack was tested on syngas from the gasifier. Both achieved steady-state operation with a 22% and 15% drop in performance, respectively, relative to pure hydrogen. In addition, tar tolerance testing on button cells demonstrated an upper limit of tar tolerance of approximately 1%, well above the tar output of the gasifier. The predicted system efficiency was revised down to 33% gross and 27% net system efficiency because of the results of the gasifier and fuel cell experiments. These results demonstrate the feasibility and benefits of thermally integrating a gasifier and a high-temperature fuel cell in small distributed power systems.

  9. Development of Fischer-Tropsch catalysis for gasified biomass

    OpenAIRE

    Lögdberg, Sara

    2007-01-01

    In order to secure the energy supply to an increasing population and at the same time limit the damage to Earth, i.e. avoiding a fatal climate change as a result of anthropogenic emissions of greenhouse gases (primarily CO2), immediate action is necessary. This includes reducing the energy consumption, increasing the energy conversion efficiency, and using renewable energies. The transport sector is the one most dependent on fossil energy and it stands for a significant part of the energy con...

  10. Optimal Operation of Biomass Gasifier Based Hybrid Energy System

    OpenAIRE

    Balamurugan, P.; Kumaravel, S.; Ashok, S.

    2011-01-01

    The focus of the world on renewable energy sources is growing rapidly due to its availability and environment friendliness. However, the renewable energy influenced by natural conditions is being intermittent, it is difficult to accomplish stable energy supply only by one kind of renewable energy source. In order to achieve reliability, it is necessary to integrate two or more energy sources together in an optimal way as hybrid energy system. Optimal allocation of sources, unpredictable load ...

  11. One dimensional numerical simulation of small scale CFB combustors

    Energy Technology Data Exchange (ETDEWEB)

    Gungor, Afsin [Department of Mechanical Engineering, Faculty of Engineering and Architecture, Nigde University, 51100 Nigde (Turkey)

    2009-03-15

    In this study, a one-dimensional model which includes volatilization, attrition and combustion of char particles for a circulating fluidized bed (CFB) combustor has been developed. In the modeling, the CFB combustor is analyzed in two regions: bottom zone considering as a bubbling fluidized bed in turbulent fluidization regime and upper zone core-annulus solids flow structure is established. In the bottom zone, a single-phase back-flow cell model is used to represent the solid mixing. Solids exchange, between the bubble phase and emulsion phase is a function of the bubble diameter and varies along the axis of the combustor. In the upper zone, particles move upward in the core and downward in the annulus. Thickness of the annulus varies according to the combustor height. Using the developed simulation program, the effects of operational parameters which are the particle diameter, superficial velocity and air-to-fuel ratio on net solids flux, oxygen and carbon dioxide mole ratios along the bed height and carbon content and bed temperature on the top of the riser are investigated. Simulation results are compared with test results obtained from the 50 kW Gazi University Heat Power Laboratory pilot scale unit and good agreement is observed. (author)

  12. System overview and characterization of a high-temperature, high-pressure, entrained-flow, laboratory-scale gasifier

    Energy Technology Data Exchange (ETDEWEB)

    Kelley, Madison A.; Dreyer, Christopher B.; Parker, Terence E.; Porter, Jason M., E-mail: jporter@mines.edu [Department of Mechanical Engineering, Colorado School of Mines, Golden, Colorado 80401 (United States); Jakulewicz, Micah S. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2015-05-15

    The high-temperature, high-pressure, entrained-flow, laboratory-scale gasifier at the Colorado School of Mines, including the primary systems and the supporting subsystems, is presented. The gasifier is capable of operating at temperatures and pressures up to 1650 °C and 40 bar. The heated section of the reactor column has an inner diameter of 50 mm and is 1 m long. Solid organic feedstock (e.g., coal, biomass, and solid waste) is ground into batches with particle sizes ranging from 25 to 90 μm and is delivered to the reactor at feed rates of 2–20 g/min. The maximum useful power output of the syngas is 10 kW, with a nominal power output of 1.2 kW. The initial characterization and demonstration results of the gasifier system with a coal feedstock are also reported.

  13. Biomass energy conversion: conventional and advanced technologies

    International Nuclear Information System (INIS)

    Increasing interest in biomass energy conversion in recent years has focused attention on enhancing the efficiency of technologies converting biomass fuels into heat and power, their capital and operating costs and their environmental emissions. Conventional combustion systems, such as fixed-bed or grate units and entrainment units, deliver lower efficiencies (<25%) than modem coal-fired combustors (30-35%). The gasification of biomass will improve energy conversion efficiency and yield products useful for heat and power generation and chemical synthesis. Advanced biomass gasification technologies using pressurized fluidized-bed systems, including those incorporating hot-gas clean-up for feeding gas turbines or fuel cells, are being demonstrated. However, many biomass gasification processes are derivatives of coal gasification technologies and do not exploit the unique properties of biomass. This paper examines some existing and upcoming technologies for converting biomass into electric power or heat. Small-scale 1-30 MWe units are emphasized, but brief reference is made to larger and smaller systems, including those that bum coal-biomass mixtures and gasifiers that feed pilot-fuelled diesel engines. Promising advanced systems, such as a biomass integrated gasifier/gas turbine (BIG/GT) with combined-cycle operation and a biomass gasifier coupled to a fuel cell, giving cycle efficiencies approaching 50% are also described. These advanced gasifiers, typically fluid-bed designs, may be pressurized and can use a wide variety of biomass materials to generate electricity, process steam and chemical products such as methanol. Low-cost, disposable catalysts are becoming available for hot-gas clean-up (enhanced gas composition) for turbine and fuel cell systems. The advantages, limitations and relative costs of various biomass gasifier systems are briefly discussed. The paper identifies the best known biomass power projects and includes some information on proposed and

  14. 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...

  15. Commissioning an Engineering Scale Coal Gasifier

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-07-01

    This report explains the development, commissioning, and testing of an engineering scale slagging coal gasifier at PNNL. The initial objective of this project was to commission the gasifier with zero safety incidents. The commissioning work was primarily an empirical study that required an engineering design approach. After bringing the gasifier on-line, tests were conducted to assess the impact of various operating parameters on the synthesis gas (syngas) product composition. The long-term intent of this project is to produce syngas product for use by internal Pacific Northwest National Laboratory (PNNL) researchers in catalyst, materials, 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 greater than 4 hours using coal feedstock. In addition, alternate designs that allow for increased flexibility regarding the fuel sources that can be used for syngas production is desired. Continued modifications to the fuel feed system will be pursued to address these goals. Alternative feed mechanisms such as a coal/methanol slurry are being considered.

  16. Results from tests of a Stirling engine and wood chips gasifier plant

    DEFF Research Database (Denmark)

    Carlsen, Henrik; Bovin, Jonas Kabell; Werling, J.;

    2002-01-01

    The combination of thermal gasification and a Stirling engine is an interesting concept for use in small Combined Heat and Power (CHP) plants based on biomass, because the need for gas cleaning is eliminated and problems with fouling of the Stirling engine heater are considerably reduced....... Furthermore, the overall electric efficiency of the system can be improved. At the Technical University of Denmark a small CHP plant based on a Stirling engine and an updraft gasifier has been developed and tested successfully. The advantages of updraft gasifiers are the simplicity and that the amount...... of the Stirling engine reduces the problems with tar to a minor problem in the design of the burner. The Stirling engine, which has an electric power output of 35 kW, is specifically designed for utilisation of fuels with a content of particles. The gas burner for the engine is designed for low specific energy...

  17. Soil bioremediation at CFB Trenton: evaluation of bioremediation processes

    International Nuclear Information System (INIS)

    Bioremediation processes and their application in the cleanup of contaminated soil, were discussed. The petroleum contaminated soil at CFB Trenton, was evaluated to determine which bioremediation process or combination of processes would be most effective. The following processes were considered: (1) white hot fungus, (2) Daramend proprietary process, (3) composting, (4) bioquest proprietary bioremediation processes, (5) Hobbs and Millar proprietary bioremediation process, and (6) farming. A brief summary of each of these options was included. The project was also used as an opportunity to train Latvian and Ukrainian specialists in Canadian field techniques and laboratory analyses. Preliminary data indicated that bioremediation is a viable method for treatment of contaminated soil. 18 refs., 3 figs

  18. Three-dimensional modeling of olive cake combustion in CFB

    International Nuclear Information System (INIS)

    A comprehensive three-dimensional numerical model which includes gas–solid flow, chemical reaction, heat transfer and mass transfer has been established, to simulate the combustion of olive cake in circulating fluidized bed (CFB) reactor. The gas flow is solved by large eddy simulation (LES) approach. The particle phase is modeled by discrete particle method, in which the drag force, gravity, particle contact force and static-dynamic friction force are taken into account. The reactive model includes pyrolysis, combustion of char and volatile matters, SO2 emission, NO and N2O emissions, which has been coupled with gas–solid flow. Simulations were carried out in a CFB riser (diameter of 0.125 m and height of 1.8 m). Flow patterns, axial and radial distributions of voidage, gas and particle velocities, profiles of temperature and gas compositions under different operating conditions were obtained. The gas pollutant emissions in a riser were highly focused on. The results showed that gas and solid temperatures increase along the riser which reveals that waste combustion mainly takes place in the upper regions of the riser. The NO and N2O concentrations reach the peak values above the fuel inlet level owing to the equilibrium between the formation and reduction reactions. The SO2 concentration peaks close to the fuel inlet. An increase in excess air ratio causes the increase of NO and N2O emissions. However, no obvious variation tendency is observed for the SO2 emission. - Highlights: • A three-dimensional Eulerian-Lagrangian numerical model was established. • The gas–solid flow and chemical reactions were simultaneously simulated. • The temperatures of gas and solid phases increase along the riser. • The predicted NO and N2O emissions increase with the increasing excess air ratio. • No obvious change is observed for the SO2 emission when excess air increases

  19. Issues Impacting Refractory Service Life in Biomass/Waste Gasification

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, J.P.; Kwong, K.-S.; Powell, C.A.

    2007-03-01

    Different carbon sources are used, or are being considered, as feedstock for gasifiers; including natural gas, coal, petroleum coke, and biomass. Biomass has been used with limited success because of issues such as ash impurity interactions with the refractory liner, which will be discussed in this paper.

  20. EVALUATION OF A PROCESS TO CONVERT BIOMASS TO METHANOL FUEL

    Science.gov (United States)

    The report gives results of a review of the design of a reactor capable of gasifying approximately 50 lb/hr of biomass for a pilot-scale facility to develop, demonstrate, and evaluate the Hynol Process, a high-temperature, high-pressure method for converting biomass into methanol...

  1. Survey of biomass gasification. Volume III. Current technology and research

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-04-01

    This survey of biomass gasification was written to aid the Department of Energy and the Solar Energy Research Institute Biological and Chemical Conversion Branch in determining the areas of gasification that are ready for commercialization now and those areas in which further research and development will be most productive. Chapter 8 is a survey of gasifier types. Chapter 9 consists of a directory of current manufacturers of gasifiers and gasifier development programs. Chapter 10 is a sampling of current gasification R and D programs and their unique features. Chapter 11 compares air gasification for the conversion of existing gas/oil boiler systems to biomass feedstocks with the price of installing new biomass combustion equipment. Chapter 12 treats gas conditioning as a necessary adjunct to all but close-coupled gasifiers, in which the product is promptly burned. Chapter 13 evaluates, technically and economically, synthesis-gas processes for conversion to methanol, ammonia, gasoline, or methane. Chapter 14 compiles a number of comments that have been assembled from various members of the gasifier community as to possible roles of the government in accelerating the development of gasifier technology and commercialization. Chapter 15 includes recommendations for future gasification research and development.

  2. Effectiveness of briquetting bio mass materials with different ratios in 10 kW down draft gasifier

    OpenAIRE

    K.sivakumar; B. Sivaraman; N.Krishna Mohan

    2011-01-01

    This paper discuss about the effectiveness of using Briquetting of rural bio mass material in Down draft gasifier for easy operation and power generation, during winter and rainy season. Sawdust a milling residue is available in huge quantity. Apart from the problems of transportation, storage, and handling, the direct burning of loosesaw dust biomass in conventional grates is associated with very low thermal efficiency and widespread air pollution. The conversion efficiency is as low as 40% ...

  3. Tunable Diode Laser Sensors to Monitor Temperature and Gas Composition in High-Temperature Coal Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, Ronald [Stanford Univ., CA (United States); Whitty, Kevin [Univ. of Utah, Salt Lake City, UT (United States)

    2014-12-01

    The integrated gasification combined cycle (IGCC) when combined with carbon capture and storage can be one of the cleanest methods of extracting energy from coal. Control of coal and biomass gasification processes to accommodate the changing character of input-fuel streams is required for practical implementation of integrated gasification combined-cycle (IGCC) technologies. Therefore a fast time-response sensor is needed for real-time monitoring of the composition and ideally the heating value of the synthesis gas (here called syngas) as it exits the gasifier. The goal of this project was the design, construction, and demonstration an in situ laserabsorption sensor to monitor multiple species in the syngas output from practical-scale coal gasifiers. This project investigated the hypothesis of using laser absorption sensing in particulateladen syngas. Absorption transitions were selected with design rules to optimize signal strength while minimizing interference from other species. Successful in situ measurements in the dusty, high-pressure syngas flow were enabled by Stanford’s normalized and scanned wavelength modulation strategy. A prototype sensor for CO, CH4, CO2, and H2O was refined with experiments conducted in the laboratory at Stanford University, a pilot-scale at the University of Utah, and an engineering-scale gasifier at DoE’s National Center for Carbon Capture with the demonstration of a prototype sensor with technical readiness level 6 in the 2014 measurement campaign.

  4. Performance of Open Core Gasifier with Briquette of different Crop Residues

    Directory of Open Access Journals (Sweden)

    M.S. Khardiwar*1 ,

    2014-05-01

    Full Text Available The open core gasifier was designed for loose agricultural residues like soybean briquette, pigeon pea briquette and mix briquette of (soybean + pigeon pea. In this experiment using air in gasification as supplementation mode there result found better as air suction mode there was less tar and gas quality. The gasifier performance was evaluated in terms of fuel consumption rate, calorific value of producer gas and gasification efficiency. Optimum value of specific gasification rate for gasification of briquette of mix biomass in open core gasifier reactor is 252 kg/h- m2 . The lower heating value of producer gas under the optimum operating conditions is about 4.10 - 4.57 (MJ/m3 .The pigeon pea briquette has show the maximum temperature in oxidation zone was 1397 ˚C.which as higher the ash fusion temperature increase. The flame Temperature of soybean briquette, pigeon pea briquette, and mix briquette is 624, 634, and 619 ˚C respectively is attained at the burner. Gasification efficiency of soybean briquette, pigeon pea briquette and mix briquette of (soybean + pigeon pea. 56%, 51%, 53%, respectively. The gas produced from the briquette could used to replace the coal and wood.

  5. 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)

  6. Investigations in gasification of biomass mixtures using thermodynamic equilibrium and semi-equilibrium models

    Energy Technology Data Exchange (ETDEWEB)

    Buragohain, Buljit; Mahanta, Pinakeswar; Moholkar, Vijayanand S. [Center for Energy, Indian Institute of Technology Guwahati, Guwahati - 781 039, Assam (India)

    2011-07-01

    Biomass gasifiers with power generation capacities exceeding 1 MW have large biomass consumption. Availability of a single biomass in such large quantities is rather difficult, and hence, mixtures of biomasses need to be used as feed-stock for these gasifiers. This study has assessed feasibility of biomass mixtures as fuel in biomass gasifiers for decentralized power generation using thermodynamic equilibrium and semi-equilibrium (with limited carbon conversion) model employing Gibbs energy minimization. Binary mixtures of common biomasses found in northeastern states of India such as rice husk, bamboo dust and saw dust have been taken for analysis. The potential for power generation from gasifier has been evaluated on the basis of net yield (in Nm3) and LHV (in MJ/Nm3) of the producer gas obtained from gasification of 100 g of biomass mixture. The results of simulations have revealed interesting trends in performance of gasifiers with operating parameters such as air ratio, temperature of gasification and composition of the biomass mixture. For all biomass mixtures, the optimum air ratio is {approx} 0.3 with gasification temperature of 800oC. Under total equilibrium conditions, and for engine-generator efficiency of 30%, the least possible fuel consumption is found to be 0.8 kg/kW-h. As revealed in the simulations with semi-equilibrium model, this parameter shows an inverse variation with the extent of carbon conversion. For low carbon conversions ({approx} 60% or so), the specific fuel consumption could be as high as 1.5 kg/kW-h. The results of this study have also been compared with previous literature (theoretical as well as experimental) and good agreement has been found. This study, thus, has demonstrated potential of replacement of a single biomass fuel in the gasifier with mixtures of different biomasses.

  7. CFB cyclones at high temperature: Operational results and design assessment

    Institute of Scientific and Technical Information of China (English)

    Raf Dewil; Jan Baeyens; Bart Caerts

    2008-01-01

    Pressure drop and cut size measurements are reported for a full scale cyclone operating within a 58 MWth CFB-combustor unit at 775℃.The paper reviews the vast number of equations to calculate the pressure drop and separation efficiency of cyclones, generally for operation at ambient temperature and at low Cs[0.5]. None of the literature correlations predicts the pressure drop with a fair accuracy within the range of experimental operating conditions. The cut size d50 can be estimated using direct empirical methods or using the Stokes number, Stk50. Both methods were used to compare measured and predicted values of d50. With the exception of Muschelknautz and Krambrock, none of the equations made accurate predictions.Finally, an alternative method to determine the friction factor of the pressure drop equation (Euler number, Eu) and of the cut size is proposed. The Eu number is determined from the geometry of common cyclones, and the derived value of Stk50 defines more accurate cut sizes. The remaining discrepancy of less than 5%, when compared with the measured values, is tentatively explained in terms of a reduced cyclone diameter due to the solids layer formed near its wall. Further measurements, mostly using positron emission particle tracking, elucidate the particle motion in the cyclone and both tracking results and the influence of the particle movement on Eu and Stk50 will be discussed in a follow-up paper.

  8. Analysis of combustion efficiency in CFB coal combustors

    Energy Technology Data Exchange (ETDEWEB)

    Afsin Gungor [Nigde University, Nigde (Turkey). Department of Mechanical Engineering, Faculty of Engineering and Architecture

    2008-06-15

    Fluidized bed technology is well known for its high combustion efficiency and is widely used in coal combustion. In this study, the combustor efficiency has been defined and investigated for CFB coal combustor based on the losses using a dynamic 2D model. The model is shown to agree well with the published data. The effect of operating parameters such as excess air ratio, bed operational velocity, coal particle diameter and combustor load and the effect of design variables such as bed height and bed diameter on the mean bed temperature, the overall CO emission and the combustion efficiency are analyzed for the small-scale of CFBC in the presently developed model. As a result of this analysis, it is observed that the combustion efficiency decreases with increasing excess air value. The combustion efficiency increases with the bed operational velocity. Increasing coal particle size results in higher combustion efficiency values. The coal feed rate has negative effect on the combustion efficiency. The combustor efficiency considerably increases with increasing combustor height and diameter if other parameters are kept unchanged. 46 refs., 16 figs., 6 tabs.

  9. Thermodynamics analysis of refinery sludge gasification in adiabatic updraft gasifier.

    Science.gov (United States)

    Ahmed, Reem; Sinnathambi, Chandra M; Eldmerdash, Usama; Subbarao, Duvvuri

    2014-01-01

    Limited information is available about the thermodynamic evaluation for biomass gasification process using updraft gasifier. Therefore, to minimize errors, the gasification of dry refinery sludge (DRS) is carried out in adiabatic system at atmospheric pressure under ambient air conditions. The objectives of this paper are to investigate the physical and chemical energy and exergy of product gas at different equivalent ratios (ER). It will also be used to determine whether the cold gas, exergy, and energy efficiencies of gases may be maximized by using secondary air injected to gasification zone under various ratios (0, 0.5, 1, and 1.5) at optimum ER of 0.195. From the results obtained, it is indicated that the chemical energy and exergy of producer gas are magnified by 5 and 10 times higher than their corresponding physical values, respectively. The cold gas, energy, and exergy efficiencies of DRS gasification are in the ranges of 22.9-55.5%, 43.7-72.4%, and 42.5-50.4%, respectively. Initially, all 3 efficiencies increase until they reach a maximum at the optimum ER of 0.195; thereafter, they decline with further increase in ER values. The injection of secondary air to gasification zone is also found to increase the cold gas, energy, and exergy efficiencies. A ratio of secondary air to primary air of 0.5 is found to be the optimum ratio for all 3 efficiencies to reach the maximum values. PMID:24672368

  10. Process for electrochemically gasifying coal using electromagnetism

    Science.gov (United States)

    Botts, Thomas E.; Powell, James R.

    1987-01-01

    A process for electrochemically gasifying coal by establishing a flowing stream of coal particulate slurry, electrolyte and electrode members through a transverse magnetic field that has sufficient strength to polarize the electrode members, thereby causing them to operate in combination with the electrolyte to electrochemically reduce the coal particulate in the slurry. Such electrochemical reduction of the coal produces hydrogen and carbon dioxide at opposite ends of the polarized electrode members. Gas collection means are operated in conjunction with the process to collect the evolved gases as they rise from the slurry and electrolyte solution.

  11. Coating for gasifiable carbon-graphite fibers

    Science.gov (United States)

    Harper-Tervet, Jan (Inventor); Dowler, Warren L. (Inventor); Yen, Shiao-Ping S. (Inventor); Mueller, William A. (Inventor)

    1982-01-01

    A thin, uniform, firmly adherent coating of metal gasification catalyst is applied to a carbon-graphite fiber by first coating the fiber with a film-forming polymer containing functional moieties capable of reaction with the catalytic metal ions. Multivalent metal cations such as calcium cross-link the polymer such as a polyacrylic acid to insolubilize the film by forming catalytic metal macro-salt links between adjacent polymer chains. The coated fibers are used as reinforcement for resin composites and will gasify upon combustion without evolving conductive airborne fragments.

  12. Final stage of first supercritical 460MW{sub e} CFB boiler construction. First experience

    Energy Technology Data Exchange (ETDEWEB)

    Goral, Damian [Foster Wheeler Energia Polska (Poland); Ostrowski, Waldemar [PKE (Poland)

    2009-07-01

    Circulating fluidized bed (CFB) boiler technology has been growing in size and number over the past two decades and it has established its position as utility scale boiler technology. Plant sizes up to 300 MW{sub e} are in operation today and designs for larger boilers are being developed. The next natural step for CFB technology is to go for supercritical steam parameters and larger boiler sizes. A Polish utility company Poludniowy Koncern Energetyczny SA (PKE) placed an order to Foster Wheeler Energia Oy for a 460 MW{sub e} supercritical CFB boiler for their Lagisza power plant. Contract was signed at the end of year 2002 and the engineering work is now ongoing. This will be the first supercritical once-through CFB boiler in the world. A modern power plant is designed for high efficiency not only for economical reasons but also for enhanced environmental performance in terms of reduced emissions and quantity of ash generated due to lower fuel consumption. Cutting CO{sub 2} emissions is one of the main drivers. To achieve these goals, supercritical steam parameters have been applied. Now this technology is available also for CFB technology. This combines a high plant efficiency with the other well known benefits of CFB technology, such as: fuel flexibility, low emissions and high availability. The boiler design for 460 MW{sub e} Lagisza power plant utilizes low mass flux BENSON Vertical once-through technology developed and licensed by Siemens AG, Germany. CFB boiler with low and uniform furnace heat flux is extremely well suited for the Benson technology providing a stable operation of the boiler also during load changes and abnormal operation conditions. The paper describes the 460 MW{sub e} supercritical CFB boiler concept and presents the technical solutions of the boiler design with auxiliary equipment, as well as first experiences from boiler erection period and commissioning. In spite of achieving this remarkable milestone the development of the CFB

  13. Development of Flexi-Burn™ CFB Power Plant to Meet the Challenge of Climate Change

    Science.gov (United States)

    Hackt, Horst; Fant, Zhen; Seltzert, Andrew; Hotta, Arto; Erikssoni, Timo; Sippu, Ossi

    Carbon-dioxide capture and storage (CCS) offers the potential for major reductions in carbon- dioxide emissions of fossil fuel-based power generation in the fairly short term, and oxyfuel combustion is one of the identified CCS technology options. Foster Wheeler (FW) is working on reduction of carbon-dioxide with its integrated Flexi-Burn™ CFB technology. The proven high efficiency circulating fluidized-bed (CFB) technology, when coupled with air separation units and carbon purification units, offers a solution for carbon dioxide reduction both in re-powering and in greenfield power plants. CFB technology has the advantages over pulverized coal technology of a more uniform furnace heat flux, increased fuel flexibility and offers the opportunity to further reduce carbon dioxide emissions by co-firing coal with bio-fuels. Development and design of an integrated Flexi-Bum™ CFB steam generator and balance of plant system was conducted for both air mode and oxyfuel mode. Through proper configuration and design, the same steam generator can be switched from air mode to oxyfuel mode without the need for unit shutdown for modifications. The Flexi-Burn™ CFB system incorporates features to maximize plant efficiency and power output when operating in the oxy-firing mode through firing more fuel in the same boiler.

  14. A dual fired downdraft gasifier system to produce cleaner gas for power generation: Design, development and performance analysis

    International Nuclear Information System (INIS)

    The existing biomass gasifier systems have several technical challenges, which need to be addressed. They are reduction of impurities in the gas, increasing the reliability of the system, easy in operation and maintenance. It is also essential to have a simple design of gasifier system for power generation, which can work even in remote locations. A dual fired downdraft gasifier system was designed to produce clean gas from biomass fuel, used for electricity generation. This system is proposed to overcome a number of technical challenges. The system is equipped with dry gas cleaning and indirect gas cooling equipment. The dry gas cleaning system completely eliminates wet scrubbers that require large quantities of water. It also helps to do away with the disposal issues with the polluted water. With the improved gasifier system, the tar level in the raw gas is less than 100 mg Nm−3.Cold gas efficiency has improved to 89% by complete gasification of biomass and recycling of waste heat into the reactor. Several parameters, which are considered in the design and development of the reactors, are presented in detail with their performance indicators. - Highlights: • Hot air injection in dual fired reactor reduces the tar content to less than 100 mg Nm−3. • In clean gas the tar content is 35 mg Nm−3 and the dust content is nil. • The specific gasification rate is 2.8 Nm3 kg−1 of fuel wood and cold gas efficiency is 89.7%. • CV of the gas: 5.3 MJ Nm−3, SFC: 1.1 kg kWh−1 and wood to power efficiency: 21%. • Cold gas efficiency is improved by optimizing the reactor's design and recycling the waste heat from hot gas

  15. Thermodynamics second law efficiency analysis for high temperature biomass gasification

    International Nuclear Information System (INIS)

    The key challenge for biomass-based system is to develop efficient conversion technologies to reduce impact of ecological drawbacks. The development of efficient technologies for biomass gasification requires correct use of thermodynamics. This paper addresses gasifier performance analysis based on the second law of thermodynamics to quantify irreversibilities in biomass gasification process at high temperatures in the range 800K-1400K. The analysis is based on exegetic model that account for the quality of energy by means of irreversibilities. (author)

  16. Biomass Thermochemical Conversion Program. 1984 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Schiefelbein, G.F.; Stevens, D.J.; Gerber, M.A.

    1985-01-01

    The objective of the program is to generate scientific data and conversion process information that will lead to establishment of cost-effective process for converting biomass resources into clean fuels. The goal of the program is to develop the data base for biomass thermal conversion by investigating the fundamental aspects of conversion technologies and by exploring those parameters that are critical to the conversion processes. The research activities can be divided into: (1) gasification technology; (2) liquid fuels technology; (3) direct combustion technology; and (4) program support activities. These activities are described in detail in this report. Outstanding accomplishments during fiscal year 1984 include: (1) successful operation of 3-MW combustor/gas turbine system; (2) successful extended term operation of an indirectly heated, dual bed gasifier for producing medium-Btu gas; (3) determination that oxygen requirements for medium-Btu gasification of biomass in a pressurized, fluidized bed gasifier are low; (4) established interdependence of temperature and residence times on biomass pyrolysis oil yields; and (5) determination of preliminary technical feasibility of thermally gasifying high moisture biomass feedstocks. A bibliography of 1984 publications is included. 26 figs., 1 tab.

  17. Fault Analysis and Innovation in Slag Discharge System of 440-t/h CFB Boiler

    Institute of Scientific and Technical Information of China (English)

    Xu Qisheng; Song Jinghui

    2009-01-01

    @@ CFB boilers have been widely used in China in recent years with their perfect performances in coal adaptability,load variation capability and lower pollutant emission.The No.3 135-MW CFB unit in Lianzhou Power Plant is the first 440-t/h series CFB unit in Guangdong Province.It finished 72-hour trial operation in Feb.2004 and was transferred to trial operation.During the trial operation and the next commercial operation,there were some problems happened in the boiler slag discharging system,seriously affecting the safe and reliable operation and the loading capability.After innovation,these problems have been completely solved.Hopefidly the solutions may be used for reference to the units with similar problems.

  18. Static and Transient Performance Prediction for CFB Boilers Using a Bayesian—Gaussian Neural Network

    Institute of Scientific and Technical Information of China (English)

    HaiwenYe; WeidouNi

    1997-01-01

    A bayesian-Gaussian Neural Network(BGNN)is put forward in this paper to predict the static and transient performance of Circulating Fluidized Bed(CFB) boilers.The advantages of this network over Back-Propagation Neural Networks(BPNNs),easier determination of topology,simpler and time saving in training process as well as self-organizing bility,make this network more practical in on-line performance prediction for complicatied processes,Simulation shows that this network is comparable to the BPNNs in predicting the performance of CFB boilers.Good and practical on-line performance predictions are essential for operation guide and model predictive control of CFB boilers,which are under research by the authors.

  19. Exergy analysis of biomass-to-synthetic natural gas (SNG) process via indirect gasification of various biomass feedstock

    International Nuclear Information System (INIS)

    This paper presents an exergy analysis of SNG production via indirect gasification of various biomass feedstock, including virgin (woody) biomass as well as waste biomass (municipal solid waste and sludge). In indirect gasification heat needed for endothermic gasification reactions is produced by burning char in a separate combustion section of the gasifier and subsequently the heat is transferred to the gasification section. The advantages of indirect gasification are no syngas dilution with nitrogen and no external heat source required. The production process involves several process units, including biomass gasification, syngas cooler, cleaning and compression, methanation reactors and SNG conditioning. The process is simulated with a computer model using the flow-sheeting program Aspen Plus. The exergy analysis is performed for various operating conditions such as gasifier pressure, methanation pressure and temperature. The largest internal exergy losses occur in the gasifier followed by methanation and SNG conditioning. It is shown that exergetic efficiency of biomass-to-SNG process for woody biomass is higher than that for waste biomass. The exergetic efficiency for all biomass feedstock increases with gasification pressure, whereas the effects of methanation pressure and temperature are opposite for treated wood and waste biomass.

  20. The Effect of Oxygen Staging on Nitrogen Conversion in Oxy-Fuel CFB Environment

    OpenAIRE

    Jankowska Sylwia; Czakiert Tomasz; Krawczyk Grzegorz; Borecki Paweł; Jesionowski Łukasz; Nowak Wojciech

    2014-01-01

    This paper presents a study on nitrogen conversion in oxy-fuel coal combustion in a pilot scale CFB 0.1 MWth facility. The paper is focused on fuel-N behaviour in the combustion chamber when the combustion process is accomplished under oxy-fuel CFB conditions. The analysis is based on infurnace sampling of flue gas and calculations of the conversion ratios of fuel-nitrogen (fuel-N) to NO, NO2, N2O, NH3 and HCN. For the tests, O2/CO2 mixtures with the oxygen content of 21 vol.% (primary gas) a...

  1. Study and design of platen superheater of 300 MW CFB boiler

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Man; Lv, Qinggang; Sun, Yunkai [Chinese Academy of Sciences, Beijing (China). Inst. of Engineering Thermophysics; Jiang, Xiaoguo [Harbin Boiler Company Limited, Harbin (China)

    2013-07-01

    In order to avoid overtemperature tube explosion of the platen superheater, the measurements of metal temperatures and the heat transfer coefficients of the platen superheater in a commercial 300 MW Circulating Fluidized Bed (CFB) boiler are conducted in this work. The measured data is analyzed and the theoretical calculation is made. On the basis, the reasonable steam flow path and the value range of heat transfer coefficient of the middle temperature platen superheater are applied for design. Furthermore, based on operation experience from several 300 MW CFB boilers, a design principle of the mass velocity and the arrangement of the platen superheater in the furnace is given.

  2. Chemical challenges to structural materials in oxyfuel-cofiring of coal and biomass

    Directory of Open Access Journals (Sweden)

    M.C. Mayoral

    2013-01-01

    Full Text Available Oxy-firing of solid fuels is one of the most relevant technological alternatives aiming at the CO2 capture in large-scale power plants. If oxy-firing is carried out in a fluidized bed reactor, the possibilities for application are extended to low-rank coals, difficult wastes, or biomass. The oxy-co-combustion of coal and biomass in circulating fluidized bed (CFB reactors would result in a negative balance for the CO2 emissions.

  3. Use of fuzzy logic to control a gasifier biomass ventilation system and maintenance of the temperature in the oxidation zone; Uso da logica fuzzy para controle do sistema de ventilacao de um gaseificador de biomassa e manutencao da temperatura da zona de oxidacao

    Energy Technology Data Exchange (ETDEWEB)

    Rezende, Oscar L.T.; Kulitz, Hans H. [Instituto Federal de Educacao, Ciencia e Tecnologia do Espirito Santo (IFES), Vitoria, ES (Brazil); Silva, Jadir N.; Galvarro, Svetlana F.S.; Machado, Cassio [Universidade Federal de Vicosa (UFV), MG (Brazil)], E-mail: oscar@ifes.edu.br

    2012-11-01

    This study aims at developing a fuzzy-based algorithm to control the frequency applied to the motor of a gasifier ventilation system in order to ensure adequate temperature in the oxidation zone and produce good quality gas. The input variables of the fuzzy controller were: error, which determines the difference between the desired temperature and the temperature at a given instant; and temperature variation, which will inform if it is increasing or decreasing at a given instant. The response variable was the operation frequency of the ventilation system motor. The rule base was built based on experimental data. The tests with the control algorithm allowed us to see that it is possible to control the oxidation zone temperature - producing gas in a stable way, which does not occur in gasification processes without ventilation system control. (author)

  4. 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...

  5. Experiences with RDF pellets in a gasifier

    International Nuclear Information System (INIS)

    Decreasing dependence upon landfills means MSW recycling and organic diversion programs grow but there is still waste remaining. A community near Toronto is turn the residuals into pellets augmented with high calorific value industry wastes. The pellet fuel has reduced ash, trace metal, and halogen concentrations when compared to MSW. Some of these pellets are being used to heat a greenhouse in southwestern Ontario using a chain grate gasifier and boiler system. This paper discusses some of the results of the initial operation and testing of a pair of these units. The gasifier has evolved and is currently rated at 20.2 GJ/h, consuming up to 940 kg/h of RDF pellets or the thermal equivalent in wood pellets. Twounits, with hot water storage tanks, are sufficient to satisfy the greenhouses 50 GJ/hr heating needs. The units boiler exhausts are treated with powdered lime before passing through separate fabric filter systems. One fabric filter was equipped with REMEDIA bags for PCDD/F removal, the other had a typical fibreglass filter. A combination of recirculated flue gas and fresh combustion air is blown up through the grate and fuel bed, into three independently controlled combustion zones. Under fire air oxygen levels are used to control temperatures within the gasification chamber. A smaller unit, 3.78 GJ/h capacity, was tested twice in 2008 and the current version was tested in early 2009. More tests are planned for the spring of 2010. While the tests have generally shown excellent emission performance, mercury, chlorine, and PCDD/F have been higher than anticipated. The finding of elevated levels of Cl2 in the exhaust gasses has been suggested as the main reason for the unusually high PCDD/F emissions. The findings related to chlorine and PCDD/F in this process is the main thrust of the paper. (author)

  6. 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.

  7. Thermal-hydraulic analysis of a 600 MW supercritical CFB boiler with low mass flux

    International Nuclear Information System (INIS)

    Supercritical Circulating Fluidized Bed (CFB) boiler becomes an important development trend for coal-fired power plant and thermal-hydraulic analysis is a key factor for the design and operation of water wall. According to the boiler structure and furnace-sided heat flux, the water wall system of a 600 MW supercritical CFB boiler is treated in this paper as a flow network consisting of series-parallel loops, pressure grids and connecting tubes. A mathematical model for predicting the thermal-hydraulic characteristics in boiler heating surface is based on the mass, momentum and energy conservation equations of these components, which introduces numerous empirical correlations available for heat transfer and hydraulic resistance calculation. Mass flux distribution and pressure drop data in the water wall at 30%, 75% and 100% of the boiler maximum continuous rating (BMCR) are obtained by iteratively solving the model. Simultaneity, outlet vapor temperatures and metal temperatures in water wall tubes are estimated. The results show good heat transfer performance and low flow resistance, which implies that the water wall design of supercritical CFB boiler is applicable. - Highlights: → We proposed a model for thermal-hydraulic analysis of boiler heating surface. → The model is applied in a 600 MW supercritical CFB boiler. → We explore the pressure drop, mass flux and temperature distribution in water wall. → The operating safety of boiler is estimated. → The results show good heat transfer performance and low flow resistance.

  8. ENHANCEMENT OF STRUCTURAL FOAM MATERIALS BY INCORPORATION OF GASIFIER SLAG

    Energy Technology Data Exchange (ETDEWEB)

    Olin Perry Norton; Ronald A. Palmer; W. Gene Ramsey

    2006-03-15

    As advanced gasification technology is increasingly adopted as an energy source, disposal of the resulting slag will become a problem. We have shown that gasifier slag can be incorporated into foamed glass, which is currently being manufactured as an abrasive and as an insulating material. The slag we add to foamed glass does not simply act as filler, but improves the mechanical properties of the product. Incorporation of gasifier slag can make foamed glass stronger and more abrasion resistant.

  9. Effectiveness of briquetting bio mass materials with different ratios in 10 kW down draft gasifier

    Directory of Open Access Journals (Sweden)

    K.Sivakumar

    2011-11-01

    Full Text Available This paper discuss about the effectiveness of using Briquetting of rural bio mass material in Down draft gasifier for easy operation and power generation, during winter and rainy season. Sawdust a milling residue is available in huge quantity. Apart from the problems of transportation, storage, and handling, the direct burning of loosesaw dust biomass in conventional grates is associated with very low thermal efficiency and widespread air pollution. The conversion efficiency is as low as 40% with particulate emissions in the flue gases in excess of 3000 mg/ Nm. In addition, a large percentage of unburnt carbonaceous ash has to be disposed off. Briquetting ofthe sawdust with cow dung could mitigate these pollution problems while at the same time making use of the important domestic energy resources. The easily available rural bio mass material saw dust and rurally available binder material cum bio mass cow dung is used for briquetting. This experiment was carried out with briquetting of saw dust and binder cow dung at different ratio. It is experimentally investigated at 8000C using gasification technique in a downdraft gasifier. The air flow rate and pressure drop across the gasifier has been measured. The percentage of combustible gases like H2, CO, CH4, CO2, and N2 formed during gasification are found. The calorific value of the producer gas for different ratio of briquetting biomass material has been found out. Experimental results indicate that briquetting at 75:25 ratio of sawdust and cow dung is the best suitable biomass Briquette for gasifier compared to the other two ratios considered. The result shows that the gas composition of methane is comparably high in this ratio (i.e. 75:25 than other two ratios i.e.(50:50 and (25:75. The results also show that pressure drop across the gasifier and producer gas composition increases withincrease in air flow rate. Also found that, thermal efficiency is comparatively high at 75:25 ratio briquettes

  10. Improved Gasifier Availability with Bed Material and Additives

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-07-15

    In order to valorize several feedstock, gasification is one of the technologies developed over the past decades. ECN developed the MILENA gasifier. In order for MILENA to become a commercial success, the gasifier needs to be feedstock flexible, robust and economically sound, operating with high availability. One of the characteristics of MILENA is high efficiency but with a higher tar content, compared to some other Dual Fluidized Bed (DFB) gasifiers. In order to reduce the issues that are associated with high tar levels in the product gas, the effect of a number of primary measures was studied. This paper presents results obtained in the last two years, focused on improving the gasifier availability by conducting experiments in a 25 kWth lab scale MILENA gasifier. Amongst others, gas composition, tar content and calorific value of the product gas were compared. Scanning Electron Microscope analysis was used to investigate bed material changes. Results show that Austrian olivine can be activated by Fuel B as well as by Additive A and B. The water-gas shift reaction is enhanced and the tar content is reduced significantly, especially the heavy tars that dominate the tar dew point. Activated olivine has a calcium-rich layer. The results show that with MILENA, we are able to lower and control the tar dew point, which will possibly increase the availability of a MILENA gasifier.

  11. Integrated biomass gasification combined cycle distributed generation plant with reciprocating gas engine and ORC

    OpenAIRE

    Kalina, Jacek

    2011-01-01

    Abstract The paper theoretically investigates the performance of a distributed generation plant made up of gasifier, Internal Combustion Engine (ICE) and Organic Rankine Cycle (ORC) machine as a bottoming unit. The system can be used for maximization of electricity production from biomass in the case where there is no heat demand for cogeneration plant. To analyze the performance of the gasifier a model based on the thermodynamic equilibrium approach is used. Performance of the gas...

  12. EVALUATION OF A PROCESS TO CONVERT BIOMASS TO METHANOL FUEL - PROJECT SUMMARY

    Science.gov (United States)

    The report gives results of a review of the design of a reactor capable of gasifying approximately 50 lb/hr of biomass for a pilot-scale facility to develop, demonstrate, and evaluate the Hynol Process, a high-temperature, high-pressure method for converting biomass into methanol...

  13. Real Time Flame Monitoring of Gasifier and Injectors

    Energy Technology Data Exchange (ETDEWEB)

    Zelepouga, Serguei; Saveliev, Alexei

    2011-12-31

    This project is a multistage effort with the final goal to develop a practical and reliable nonintrusive gasifier injector monitor to assess burner wear and need for replacement. The project team included the National Energy Technology Laboratory (NETL), Gas Technology Institute (GTI), North Carolina State University, and ConocoPhillips. This report presents the results of the sensor development and testing initially at GTI combustion laboratory with natural gas flames, then at the Canada Energy Technology Center (CANMET), Canada in the atmospheric coal combustor as well as in the pilot scale pressurized entrained flow gasifier, and finally the sensor capabilities were demonstrated at the Pratt and Whitney Rocketdyne (PWR) Gasifier and the Wabash River Repowering plant located in West Terre Haute, IN. The initial tests demonstrated that GTI gasifier sensor technology was capable of detecting shape and rich/lean properties of natural gas air/oxygen enriched air flames. The following testing at the Vertical Combustor Research Facility (VCRF) was a logical transition step from the atmospheric natural gas flames to pressurized coal gasification environment. The results of testing with atmospheric coal flames showed that light emitted by excited OH* and CH* radicals in coal/air flames can be detected and quantified. The maximum emission intensities of OH*, CH*, and black body (char combustion) occur at different axial positions along the flame length. Therefore, the excitation rates of CH* and OH* are distinct at different stages of coal combustion and can be utilized to identify and characterize processes which occur during coal combustion such as devolatilization, char heating and burning. To accomplish the goals set for Tasks 4 and 5, GTI utilized the CANMET Pressurized Entrained Flow Gasifier (PEFG). The testing parameters of the PEFG were selected to simulate optimum gasifier operation as well as gasifier conditions normally resulting from improper operation or

  14. Gasification technologies for heat and power from biomass

    NARCIS (Netherlands)

    Beenackers, AACM; Maniatis, K; Kaltschmitt, M; Bridgwater, AV

    1997-01-01

    A critical review is presented of biomass gasifier systems presently commercially available or under development. Advantages and possible problem areas are discussed in relation to particular applications. Both large and small scale technologies are reviewed. Catalysed by the EC JOULE and AIR progra

  15. Evaluation of the conversion efficiency of the 180Nm3/h Johansson Biomass Gasifier™

    Directory of Open Access Journals (Sweden)

    Ntshengedzeni S. Mamphweli, Edson L. Meyer

    2010-01-01

    Full Text Available Biomass gasification is the thermochemical conversion of biomass materials into a producer gas, which is a mixture of carbon monoxide, carbon dioxide, methane, hydrogen, nitrogen and water vapour. The 180Nm3/h System Johansson Biomass Gasifier (SJBG at Eskom research and Innovation Centre is used for research and development initiatives, and also for demonstration purposes. The aim of this research was to investigate the efficiency of the gasifier and. This is done through an analysis of the gas profiles at the gasifier using a custom-built gas and temperature measurement system. Non-Dispersive Infrared gas detection technique is applied to monitor the volume and quality of producer gas. Palladium/Nickel gas sensing is applied to monitor the hydrogen content in the gas stream. Temperature in the gasifier is monitored through the use of type K thermocouples. The gas and temperature sensors are connected to the data logger interfaced to a computer. The heating value of the producer gas was determined from the percentage composition of the combustible gases. Evaluation of the efficiency of this gasifier was done before the installation of a 300Nm3/h at a rural village. The gasifier achieved an efficiency of 75% with an average gas heating value of 6MJ/Nm3.

  16. 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.

  17. Technoeconomic assessment of biomass to energy

    International Nuclear Information System (INIS)

    A spreadsheet-based decision support system has been developed that allows easy evaluation of integrated biomass to electricity and biomass to ethanol systems. The Bioenergy Assessment Model (BEAM) has been developed to allow the techno-economic assessment of biomass to electricity and biomass to ethanol schemes, including investigation of the interfacing issues. Technical and economic parameters can be assessed for a variety of feedstocks, conversion technologies and generating cycles. Production modules are currently available for biomass supply from short rotation coppice and conventional forestry relevant to conditions and practices in NW Europe. The biomass conversion modules include pre-treatment (reception, storage, handling, comminution, screening and drying); atmospheric gasification (generic gasifier, wet gas scrubbing, dual fuel engine); pressure gasification (generic gasifier, hot gas filtration, gas turbine combined cycle); fast pyrolysis for liquid bio-fuel-oil (pyrolyser, oil storage, pilot-injected diesel engine); combustion (fluid bed combuster steam turbine), conventional acid hydrolysis fermentation and the NREL SSF process to ethanol. In addition there is a further module which can be used to examine the collection, mass burn and generation of electricity from MSW. BEAM has been used, and the results presented in this paper, to determine the costs of generating bio-electricity from short rotation coppice and conventional forestry over a range of power outputs and for each conversion technology. Alternative feedstock supply strategies have been examined and relations drawn between delivered feedstock cost and cost of electricity. (author)

  18. Gas Turbine Combustion and Ammonia Removal Technology of Gasified Fuels

    Directory of Open Access Journals (Sweden)

    Takeharu Hasegawa

    2010-03-01

    Full Text Available From the viewpoints of securing a stable supply of energy and protecting our global environment in the future, the integrated gasification combined cycle (IGCC power generation of various gasifying methods has been introduced in the world. Gasified fuels are chiefly characterized by the gasifying agents and the synthetic gas cleanup methods and can be divided into four types. The calorific value of the gasified fuel varies according to the gasifying agents and feedstocks of various resources, and ammonia originating from nitrogenous compounds in the feedstocks depends on the synthetic gas clean-up methods. In particular, air-blown gasified fuels provide low calorific fuel of 4 MJ/m3 and it is necessary to stabilize combustion. In contrast, the flame temperature of oxygen-blown gasified fuel of medium calorie between approximately 9–13 MJ/m3 is much higher, so control of thermal-NOx emissions is necessary. Moreover, to improve the thermal efficiency of IGCC, hot/dry type synthetic gas clean-up is needed. However, ammonia in the fuel is not removed and is supplied into the gas turbine where fuel-NOx is formed in the combustor. For these reasons, suitable combustion technology for each gasified fuel is important. This paper outlines combustion technologies and combustor designs of the high temperature gas turbine for various IGCCs. Additionally, this paper confirms that further decreases in fuel-NOx emissions can be achieved by removing ammonia from gasified fuels through the application of selective, non-catalytic denitration. From these basic considerations, the performance of specifically designed combustors for each IGCC proved the proposed methods to be sufficiently effective. The combustors were able to achieve strong results, decreasing thermal-NOx emissions to 10 ppm (corrected at 16% oxygen or less, and fuel-NOx emissions by 60% or more, under conditions where ammonia concentration per fuel heating value in unit volume was 2.4 × 102 ppm

  19. Heavy metal characterization of circulating fluidized bed derived biomass ash.

    Science.gov (United States)

    Li, Lianming; Yu, Chunjiang; Bai, Jisong; Wang, Qinhui; Luo, Zhongyang

    2012-09-30

    Although the direct combustion of biomass for energy that applies circulating fluidized bed (CFB) technology is steadily expanding worldwide, only few studies have conducted an environmental assessment of biomass ash thus far. Therefore, this study aims to integrate information on the environmental effects of biomass ash. We investigated the concentration of heavy metal in biomass ash samples (bottom ash, cyclone ash, and filter ash) derived from a CFB boiler that combusted agricultural and forest residues at a biomass power plant (2×12 MW) in China. Ash samples were gathered for the digestion and leaching test. The heavy metal content in the solution and the leachate was studied via an inductively coupled plasma-mass spectrometer and a Malvern Mastersizer 2000 mercury analyzer. Measurements for the chemical composition, particle size distribution, and the surface morphology were carried out. Most of the metals in cyclone ash particles were enriched, whereas Ti and Hg were enriched in filter ash. Residence time contributed most to heavy metal enrichment. Under HJ/T 300 conditions, the heavy metals showed serious leaching characteristics. Under EN 12457-2 conditions, leaching behavior was hardly detected. PMID:22840499

  20. Gasifiers optimized for fuel cell applications

    Science.gov (United States)

    Steinfeld, G.; Fruchtman, J.; Hauserman, W. B.; Lee, A.; Meyers, S. J.

    Conventional coal gasification carbonate fuel cell systems are typically configured so that the fuel gas is primarily hydrogen, carbon monoxide, and carbon dioxide, with waste heat recovery for process requirements and to produce additional power in a steam bottoming cycle. These systems make use of present day gasification processes to produce the low to medium Btu fuel gas which in turn is cleaned up and consumed by the fuel cell. These conventional gasification/fuel cell systems have been studied in recent years projecting system efficiencies of 45-53 percent (HHV). Conventional gasification systems currently available evolved as stand-alone systems producing low to medium Btu gas fuel gas. The requirements of the gasification process dictates high temperatures to carry out the steam/carbon reaction and to gasify the tars present in coal. The high gasification temperatures required are achieved by an oxidant which consumes a portion of the feed coal to provide the endothermic heat required for the gasification process. The thermal needs of this process result in fuel gas temperatures that are higher than necessary for most end use applications, as well as for gas cleanup purposes. This results in some efficiency and cost penalties. This effort is designed to study advanced means of power generation by integrating the gasification process with the unique operating characteristics of carbonate fuel cells to achieve a more efficient and cost effective coal based power generating system. This is to be done by altering the gasification process to produce fuel gas compositions which result in more efficient fuel cell operation and by integrating the gasification process with the fuel cell as shown in Figure 2. Low temperature catalytic gasification was chosen as the basis for this effort due to the inherent efficiency advantages and compatibility with fuel cell operating temperatures.

  1. An Experimental Investigation of Hydrogen Production from Biomass

    Institute of Scientific and Technical Information of China (English)

    吕鹏梅; 常杰; 付严; 王铁军; 陈勇; 祝京旭

    2003-01-01

    In gaseous products of biomass steam gasification, there exist a lot of CO, CH4 and other hydrocarbons that can be converted to hydrogen through steam reforming reactions. There exists potential hydrogen production from the raw gas of biomass steam gasification. In the present work, the characteristics of hydrogen production from biomass steam gasification were investigated in a small-scale fluidized bed. In these experiments, the gasifying agent (air) was supplied into the reactor from the bottom of the reactor and the steam was added into the reactor above biomass feeding location. The effects of reaction temperature, steam to biomass ratio, equivalence ratio (ER) and biomass particle size on hydrogen yield and hydrogen yield potential were investigated. The experimental results showed that higher reactor temperature, proper ER, proper steam to biomass ratio and smaller biomass particle size will contribute to more hydrogen and potential hydrogen yield.

  2. PIV MEASUREMENT OF THE GAS-SOLID FLOW PATTERN IN A CFB RISER

    Institute of Scientific and Technical Information of China (English)

    Shi Hui-xian; Wang Qin-hui; Wang Can-xing; Luo Zhong-yang; Cen Ke-fa

    2003-01-01

    Particle Imaging Velocimetry (PIV) is a valuable measuring tool for studying multiphase flows, such as liquid-gas and gas-solid flow. It can be used to carry out many hydrodynamic studies, in particular, to determine accurately the gas-solid flow structure in CFB (Circulating Fluidized Beds). In this paper, the technique characteristics was described in applying the PIV to measure the gas-solid flow in circulating fluidized beds. A primary experiment was completed on a CFB unit with the PIV, yielding the velocity vector fields of high-density particles for different gas-solid superficial velocities and solid recycle rates. Velocities of the transported particles were calculated with cross-correlation method. The major factors influencing the successful measurement of particle velocity with the PIV technique were also described.

  3. Advanced ecological and economical power plant technology based on CFB combustion

    International Nuclear Information System (INIS)

    The scenario of the power plant industry is worldwide affected by one important issue, namely the stringent and steadily increasing environment regulations. Fluidized bed boilers, based on Circulating Fluidized Bed (CFB) technology with in-situ emission control, and improved economics as well as with proven record of high efficiency and reliability meets the ecological, economical and technical requirements. It should be noted that in addition to their attractive performance, regarding efficiency and pollution control, coal fired CFB boilers have been successfully introduced not only in power plant industry, but also in other industrial units such as chemical plants, automobile industry, paper mills, cement, etc. The experience gained to date confirms the advantages and also the reliability of this technology. (author)

  4. Reburning Characteristics of Residual Carbon in Fly Ash from CFB Boilers

    Science.gov (United States)

    Zhang, S. H.; Luo, H. H.; Chen, H. P.; Yang, H. P.; Wang, X. H.

    The content of residual carbon in fly ash of CFB boilers is a litter high especially when low-grade coal, such as lean coal, anthracite coal, gangue, etc. is in service, which greatly influences the efficiency of boilers and fly ash further disposal. Reburn of fly ash through collection, recirculation in CFB furnace or external combustor is a possibly effective strategy to decrease the carbon content, mainly depending on the residual carbon reactivity. In this work, the combustion properties of residual carbon in fly ash and corresponding original coal from large commercial CFB boilers (Kaifeng (440t/h), and Fenyi (410t/h), all in china) are comparably investigated through experiments. The residual carbon involved was firstly extracted and enriched from fly ash by means of floating elutriation to mitigate the influence of ash and minerals on the combustion behavior of residual carbon. Then, the combustion characteristic of two residual carbons and the original coal particles was analyzed with thermogravimetric analyzer (TGA, STA409C from Nestch, Germany). It was observed that the ignition temperature of the residual carbon is much higher than that of original coal sample, and the combustion reactivity of residual carbon is not only dependent on the original coal property, but also the operating conditions. The influence of oxygen content and heating rate was also studied in TGA. The O2 concentration is set as 20%, 30%, 40% and 70% respectively in O2/N2 gas mixture with the flow rate of 100ml/min. It was found that higher oxygen content is favor for decreasing ignition temperature, accelerating the combustion rate of residual carbon. And about 40% of oxygen concentration is experimentally suggested as an optimal value when oxygen-enriched combustion is put into practice for decreasing residual carbon content of fly ash in CFB boilers.

  5. Gasifier-combustor using chips of eucalyptus firewood in drying pulped coffee; Gasificador/combustor a cavacos de lenha na secagem de cafe despolpado

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Jadir Nogueira da; Saiki, Emilio Takashi; Vilarinho, Mauricio Coelho; Cardoso Sobrinho, Jose [Vicosa Univ., MG (Brazil). Dept. de Engenharia Agricola

    2000-07-01

    This study aimed to determine the viability of the of a gasifier/combustor using chip of eucalyptus firewood as fuel, in drying pulped coffee. The gasifier used was designed by Silva (1988) with modifications in the gasification chamber, being the area of the grate reduced from 0,21 to 0,06m{sup 2}. An addition of a coating involving the gasifier was done and a damper was placed in the exit of the combustion chamber. The air heated up in the combustor was sent to dryer developed by Campos (1998) that possessed four movable metallic chambers with movement and hoisted by a pulleys system. It was dried coffee with initial moisture of 54,5% w.b. up to 11,1{+-}1,6% w.b. The moisture of the coffee was determined by equipment of the universal type, EDABO and stove. The temperature of the drying air was of 60 deg C, static pressure of the air in the exit of the fan of 9 mm ca with speed of 46,3m{sup 3}.min{sup -1}. It was ended that the gasifier using chips of eucalyptus firewood as fuel consumed among 15,3 and 18,8 kg/hour of the biomass and that the equipment is viable for the drying of pulped coffee, not impregnating it with smoke or other particles, usually generated in the direct fired furnaces. (author)

  6. 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.

  7. Study on drying and combustion process in 8rate-CFB incinerator

    Institute of Scientific and Technical Information of China (English)

    LI QingHai; ZHANG YanGuo; CHEN MeiQian; MENG AiHong; CHEN ChangHe

    2009-01-01

    The drying and combustion process in the combined grate and circulating fiuidized bed (grate-CFB)municipal solid waste (MSW) incinerator was investigated experimentally and mathematically. The drying grate bed was simulated by a muffle furnace, which could be controlled at a constant tempera-ture level. The kind of wastes, thickness of waste layer fed and temperature were chosen as the ad-justable parameters to study their effect on the drying process. The experimental results indicated that the hydrophilic wastes were more difficult to be dried than the hydrophobic wastes. The higher the temperature is the easier the waste is to be dried. The thinner waste layer is favorable to drying the waste. The pyrolysis experiment in the furnace showed that the higher temperature level could reduce the conversion rate of carbon to carbon monoxide. The semi-empirical mathematical model that in-cluded the bed material distribution subrnodel, volatile matter release submodel, carbon particle combustion submodel and so on was proposed. A 260 t/d grate-CFB incinerator was modeled and the model predicted bulk density agreed with the measured value from industrial field test. The predicted flue gas (e.g. CO2, CO) concentration deviated slightly from the industrial test data. The parameters and variables used in the model were determined by the experiments or practical field test. This model can be used to design the grate-CFB incinerator and guide its operation.

  8. Association of CFH and CFB Gene Polymorphisms with Retinopathy in Type 2 Diabetic Patients

    Directory of Open Access Journals (Sweden)

    Jun Wang

    2013-01-01

    Full Text Available Objectives. The complement system is a key component of innate immunity and has been implicated in the pathogenesis of diabetic retinopathy (DR. This study aimed at investigating whether polymorphisms of two genes in the complement pathway, complement factor H (CFH and complement factor B (CFB, are associated with DR. Methods. 552 well-defined subjects with type 2 diabetes, consisting of 277 DR patients and 275 diabetic controls, were recruited. Four Tag-SNPs rs1048709, rs537160, rs4151657, and rs2072633 in CFB and rs800292 (I62V in CFH were examined using TaqMan Genotyping Assays. Results. There were significant increases in the frequencies of A allele and AA genotype for rs1048709 in DR patients compared with diabetic controls (Pcorr=0.035, OR=1.42; Pcorr=0.02, OR=2.27, resp.: meanwhile, significant decreases in the frequencies of A allele and AA genotype for rs800292 were observed in DR patients compared with diabetic controls (Pcorr=0.04, OR=0.72; Pcorr=0.015, OR=0.51, resp.. Joint effect of these two loci was also identified. Moreover, rs800292/AA genotype was found to be related with delayed progression to DR. Conclusions. CFH-rs800292 and CFB-rs1048709 are associated with the presence of DR, which strengthens the concept that complement system plays an important role in the pathogenesis of DR.

  9. Low-Chrome/Chrome Free Refractories for Slagging Gasifiers

    International Nuclear Information System (INIS)

    Gasifiers are containment vessels used to react carbon-containing materials with oxygen and water, producing syngas (CO and H2) that is used in chemical and power production. It is also a potential source of H2 in a future hydrogen economy. Air cooled slagging gasifiers are one type of gasifier, operating at temperatures from 1275-1575 C and at pressures of 400 psi or higher. They typically use coal or petroleum coke as the carbon source, materials which contain ash impurities that liquefy at the gasification temperatures, producing liquid slag in quantities of 100 or more tons/day, depending on the carbon fed rate and the percent ash present in the feedstock. The molten slag is corrosive to refractory linings, causing chemical dissolution and spalling. The refractory lining is composed of chrome oxide, alumina, and zirconia; and is replaced every 3-24 months. Gasifier users would like greater on-line availability and reliability of gasifier liners, something that has impacted gasifier acceptance by industry. Research is underway at NETL to improve refractory service life and to develop a no-chrome or low-chrome oxide alternative refractory liner. Over 250 samples of no- or low-chrome oxide compositions have been evaluated for slag interactions by cup testing; with potential candidates for further studies including those with ZrO2, Al2O3, and MgO materials. The development of improved liner materials is necessary if technologies such as IGCC and DOE's Near Zero Emissions Advanced Fossil Fuel Power Plant are to be successful and move forward in the marketplace

  10. CHP from Updraft Gasifier and Stirling Engine

    OpenAIRE

    Jensen, N; Werling, J.; Carlsen, Henrik; Henriksen, Ulrik Birk

    2002-01-01

    The combination of thermal gasification with a Stirling engine is an interesting concept for use in small combined heat and power plants based on biomass. By combining the two technologies a synergism can potentially be achieved. Technical problems, e.g. gas cleaning and fouling of the Stirling engine heat exchanger, can be eliminated and the overall electric efficiency of the system can be improved. At the Technical University of Denmark a Stirling engine fueled by gasification gas has been ...

  11. Power generation in small scale from gasification of biomass; Geracao eletrica em pequena escala a partir da gaseificacao de biomassa

    Energy Technology Data Exchange (ETDEWEB)

    Lora, Electo Eduardo Silva; Andrade, Rubenildo Vieira; Aradas, Maria Eugenia Corria [Universidade Federal de Itajuba (UNIFEI), MG (Brazil). Inst. de Engenharia Mecanica. Nucleo de Excelencia em Geracao Termeletrica e Distribuida (NEST)

    2004-07-01

    This paper present a review about biomass gasifier technology and discuss its advantages, disadvantages and applications as well as shows some succeeded experiences in this area. The paper also presents an analysis of the biomass gas use in alternative engines and in new distributed generation technology such as Stirling engines and microturbines. (author)

  12. Numerical simulation of a 200 kW down draft gasifier using acai seed (Euterpe oleracea mart.) as fuel

    Energy Technology Data Exchange (ETDEWEB)

    Itai, Y.; Rocha, H.M.Z. [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Faculdade de Engenharia Mecanica]. E-mails: yuuitai@ufpa.br; hendrick@ufpa.br; Brasil, A.M. [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Faculdade de Engenharia Sanitaria e Ambiental]. E-mail: ambrasil@ufpa.br; Malico, I. [Universidade de Evora (Portugal)]. E-mail: imbm@uevora.pt

    2008-07-01

    In this work a thermochemical equilibrium model for downdraft gasifiers has been proposed. The model was compared to the model developed in Gordon and McBride (1994). The properties such as efficiency of cold gas, LHV and temperature of an Amazonian biomass Euterpe olearacea Mart. was simulated. The numerical simulations aimed the maximization of H{sub 2} and CH{sub 4} in a gasification process. The model simulated numerically the influence of the gasifying relative fuel/air ratio and the biomass moisture content on the syngas composition. Two values of moisture content 33% and 37.5% were suggested for the gasification of acai seed for the maximization of the H{sub 2} and CH{sub 4} concentrations in a range of the equivalence ratio, {phi}, between 2.3 and 4. The results also showed that to achieve the maximization of CH{sub 4} with {phi} = 4 the reaction temperature drops in average of 35.44%. (author)

  13. Development of methane and nitrous oxide emission factors for the biomass fired circulating fluidized bed combustion power plant.

    Science.gov (United States)

    Cho, Chang-Sang; Sa, Jae-Hwan; Lim, Ki-Kyo; Youk, Tae-Mi; Kim, Seung-Jin; Lee, Seul-Ki; Jeon, Eui-Chan

    2012-01-01

    This study makes use of this distinction to analyze the exhaust gas concentration and fuel of the circulating fluidized bed (CFB) boiler that mainly uses wood biomass, and to develop the emission factors of Methane (CH(4)), Nitrous oxide (N(2)O). The fuels used as energy sources in the subject working sites are Wood Chip Fuel (WCF), RDF and Refused Plastic Fuel (RPF) of which heating values are 11.9 TJ/Gg, 17.1 TJ/Gg, and 31.2 TJ/Gg, respectively. The average concentrations of CH(4) and N(2)O were measured to be 2.78 ppm and 7.68 ppm, respectively. The analyzed values and data collected from the field survey were used to calculate the emission factor of CH(4) and N(2)O exhausted from the CFB boiler. As a result, the emission factors of CH(4) and N(2)O are 1.4 kg/TJ (0.9-1.9 kg/TJ) and 4.0 kg/TJ (2.9-5.3 kg/TJ) within a 95% confidence interval. Biomass combined with the combustion technology for the CFB boiler proved to be more effective in reducing the N(2)O emission, compared to the emission factor of the CFB boiler using fossil fuel. PMID:23365540

  14. Development of Methane and Nitrous Oxide Emission Factors for the Biomass Fired Circulating Fluidized Bed Combustion Power Plant

    Directory of Open Access Journals (Sweden)

    Chang-Sang Cho

    2012-01-01

    Full Text Available This study makes use of this distinction to analyze the exhaust gas concentration and fuel of the circulating fluidized bed (CFB boiler that mainly uses wood biomass, and to develop the emission factors of Methane (CH4, Nitrous oxide (N2O. The fuels used as energy sources in the subject working sites are Wood Chip Fuel (WCF, RDF and Refused Plastic Fuel (RPF of which heating values are 11.9 TJ/Gg, 17.1 TJ/Gg, and 31.2 TJ/Gg, respectively. The average concentrations of CH4 and N2O were measured to be 2.78 ppm and 7.68 ppm, respectively. The analyzed values and data collected from the field survey were used to calculate the emission factor of CH4 and N2O exhausted from the CFB boiler. As a result, the emission factors of CH4 and N2O are 1.4 kg/TJ (0.9–1.9 kg/TJ and 4.0 kg/TJ (2.9–5.3 kg/TJ within a 95% confidence interval. Biomass combined with the combustion technology for the CFB boiler proved to be more effective in reducing the N2O emission, compared to the emission factor of the CFB boiler using fossil fuel.

  15. Straw Gasification in a Two-Stage Gasifier

    DEFF Research Database (Denmark)

    Bentzen, Jens Dall; Hindsgaul, Claus; Henriksen, Ulrik Birk;

    2002-01-01

    to maintain a high fuel reactivity, a mixture of phosphorus acid, calcium hydroxide, molasses and water was mixed into the ground pellets. Following the gasifier was running continuously for more than 50 hours as planned. Several tar, gas and particle measurements were carried out during the test...

  16. 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...

  17. Study on drying and combustion process in grate-CFB incinerator

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The drying and combustion process in the combined grate and circulating fluidized bed(grate-CFB) municipal solid waste(MSW) incinerator was investigated experimentally and mathematically.The drying grate bed was simulated by a muffle furnace,which could be controlled at a constant tempera-ture level.The kind of wastes,thickness of waste layer fed and temperature were chosen as the ad-justable parameters to study their effect on the drying process.The experimental results indicated that the hydrophilic wastes were more difficult to be dried than the hydrophobic wastes.The higher the temperature is the easier the waste is to be dried.The thinner waste layer is favorable to drying the waste.The pyrolysis experiment in the furnace showed that the higher temperature level could reduce the conversion rate of carbon to carbon monoxide.The semi-empirical mathematical model that in-cluded the bed material distribution submodel,volatile matter release submodel,carbon particle combustion submodel and so on was proposed.A 260 t/d grate-CFB incinerator was modeled and the model predicted bulk density agreed with the measured value from industrial field test.The predicted flue gas(e.g.CO2,CO) concentration deviated slightly from the industrial test data.The parameters and variables used in the model were determined by the experiments or practical field test.This model can be used to design the grate-CFB incinerator and guide its operation.

  18. Biofuels and biochemicals production from forest biomass in Western Canada

    International Nuclear Information System (INIS)

    Biomass can be used for the production of fuels, and chemicals with reduced life cycle (greenhouse gas) emissions. Currently, these fuels and chemicals are produced mainly from natural gas and other fossil fuels. In Western Canada, forest residue biomass is gasified for the production of syngas which is further synthesized to produce different fuels and chemicals. Two types of gasifiers: the atmospheric pressure gasifier (commercially known as SilvaGas) and the pressurized gasifier (commercially known as RENUGAS) are considered for syngas production. The production costs of methanol, (dimethyl ether), (Fischer-Tropsch) fuels, and ammonia are $0.29/kg, $0.47/kg, $0.97/kg, and $2.09/kg, respectively, for a SilvaGas-based gasification plant with a capacity of 2000 dry tonnes/day. The cost of producing methanol, DME, F-T fuels, and ammonia in a RENUGAS-based plant are $0.45/kg, $0.69/kg, $1.53/kg, and $2.72/kg, respectively, for a plant capacity of 2000 dry tonnes/day. The minimum cost of producing methanol, DME, F-T fuels, and ammonia are $0.28/kg, $0.44/kg, $0.94/kg, and $2.06/kg at plant capacities of 3000, 3500, 4000, and 3000 dry tonnes/day, respectively, using the SilvaGas-based gasification process. Biomass-based fuels and chemicals are expensive compared to fuels and chemicals derived from fossil fuels, and carbon credits can help them become competitive. -- Highlights: → Forest residue can be used for production of fuels and chemicals in Western Canada. → Methanol, dimethyl ether, Fischer-Tropsch fuel and ammonia are focus of this study. → This study estimates the production cost of these fuels and chemicals from biomass. → Economic optimum sizes of production plants are also estimated through modeling. → Costs of fuels and chemicals from biomass are higher than that from fossil fuels.

  19. 250 MW single train CFB cogeneration facility. Annual report, October 1993--September 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-02-01

    This Technical Progress Report (Draft) is submitted pursuant to the Terms and Conditions of Cooperative Agreement No. DE-FC21-90MC27403 between the Department of Energy (Morgantown Energy Technology Center) and York County Energy Partners, L.P. a wholly owned project company of Air Products and Chemicals, Inc. covering the period from January 1994 to the present for the York County Energy Partners CFB Cogeneration Project. The Technical Progress Report summarizes the work performed during the most recent year of the Cooperative Agreement including technical and scientific results.

  20. CFD simulation of combustion in a 150 MW{sub e} CFB boiler

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Nan; Wang, Wei; Li, Jinghai [Chinese Academy of Sciences, Beijing (China). State Key Lab. of Multiphase Complex Systems

    2013-07-01

    Eulerian granular multiphase model with meso-scale modeling of drag coefficient and mass transfer coefficient, based on the energy minimization multi-scale (EMMS) model, was presented to simulate a 150 MW{sub e} CFB boiler. The three-dimensional (3D), time-dependent simulation results were presented in terms of the profiles of pressure, the distributions of carbon and oxygen, as well as the temperature. The EMMS-based sub-grid modeling allows using coarse grid with proven accuracy, and hence it is suitable for simulation of such large-scale industrial reactors.

  1. Utilization of CFB ash in reclamation to prevent post-mining AMD

    International Nuclear Information System (INIS)

    A surface mine located in an historically acid producing area of Preston County, West Virginia was mined and reclaimed between 1990 and 1992. In an effort to prevent post-mining acid discharges, CFB (circulating fluidized bed) boiler ash was utilized in the reclamation process. This highly alkaline ash was placed on the pit floor and on top of the backfilled area in approximately a one foot layer. Initial water quality results following reclamation have shown the discharges from the ash treated areas to have a higher pH and lower metal concentrations than the discharges from the non-treated areas

  2. Coal gasifier supplying MHD-steam power plant

    International Nuclear Information System (INIS)

    An atmospheric pressure coal gasifier is combined with an MHD generator and a vapor generator to provide an entirely coal-fueled power generating system. The combustible low btu gas formed in the gasifier is passed through a gas cleaner wherein particulate matter, gaseous sulfur compounds, and char are removed to produce a clean combustible low btu gas. A first portion of the clean combustible low btu gas and the char are passed to the burner of the MHD generator as a source of fuel. A second portion of the clean combustible low btu gas is passed to a direct-fired air heater as a source of fuel for preheating the combustion air supplied to the burner of the mhd generator

  3. Biomass boilers

    OpenAIRE

    Nahodil, Jiří

    2011-01-01

    Bachelor’s thesis deals with the use of biomass for heating houses and apartment houses. The first part is dedicated to biomass. Here are mentioned the possibility of energy recovery, treatment and transformation of biomass into a form suitable for burning, its properties and combustion process itself. The second part is devoted to biomass boilers, their separation and description. The last section compares the specific biomass boiler with a boiler to natural gas, particularly from an economi...

  4. Technology is not a barrier for biomass power: Experiences from 130 biomass power plants

    Energy Technology Data Exchange (ETDEWEB)

    Aijala, M.; Hulkkonen, S.

    1998-07-01

    Finland is one of the leading countries in the utilization of biomass fuels for power production. The biomass fuels in Finland are peat and wood biomass, which are also the only indigenous fuels available. Peat and wood biomass cover about 26% of the primary energy consumption in Finland and their share in power generation is about 18% (peat 8% and wood biomass 10%). There are about 230 biomass fired boilers in operation of which 130 are used for combined heat and power (CHP) production. The wood and peat-fired power plants range in size from a small CHP plant of 5 MWe to the largest condensing plant of 154 MWe. The most common technology today for the biomass fuels is fluidized bed combustion with back pressure steam cycle for district heat or process steam production. Bubbling fluidized bed (BFB) is best for wood and peat combustion and circulating fluidized bed (CFB) is needed, when coal is wanted as a back up fuel. The largest bubbling fluidized bed in Finland has a capacity of 295 MWth using peat and wood wastes as fuels. The smallest ones are only a few MWth. Circulating fluidized bed boilers range from 25 to 290 MWth in biomass applications. Condensing power generation from solid fuels in the relatively small size scale is not economical at todays conditions. Gasification is used only in a few small heating stations. One promising application area for the gasification technology, however, is in the co-combustion processes. The peat and wood biomass fuels are good fuels from combustion point of view, and do not create any major operating problems. The investment cost biomass fired CHP plants range from ECU 1,100 to 1,800/kWe depending on the size range. The costs of electricity in the municipal CHP plants is ECU 20-35/MWh. In industrial plants with longer operating time and low fuel price the cost of electricity can be even lower than ECU 17/MWh.

  5. Mathematical model of processes of reactor with gasified fluidized bed

    International Nuclear Information System (INIS)

    An original scheme of steam generator with gasifying fluidized bed has been presented as a possible solution for reconstruction of furnace with pulverized burning of coal. The method is effective when applied in combination with desulfurization for the purpose of reducing the CO2 emissions level. A mathematical model has been developed, which determines the correlation primary (fluidizing) and (burning out) secondary air with sufficient for the practice accuracy

  6. Failure Mechanisms in High Chrome Oxide Gasifier Refractories

    Science.gov (United States)

    Bennett, James P.; Kwong, Kyei-Sing

    2011-04-01

    Gasification is a high-temperature, high-pressure chemical process used to convert a carbon feedstock into CO and H2 (syngas) for use in power generation and the production of chemicals. It is also a leading candidate as a source of hydrogen in a hydrogen economy and is one of several technologies expected to see increased use in advanced fossil fuel power systems in the future. Gasification is being evaluated because of its high efficiency, its ability to capture CO2 for sequestration or reuse in other applications, and its potential for carbon feedstock fuel flexibility. At the heart of the gasification process is a gasifier, a high pressure chemical reaction vessel used to contain the interactions between carbon and water in a shortage of oxygen, producing syngas. The gasifier is lined with high chrome oxide materials to protect the containment vessel. Gasifiers are complex systems, and failure of the refractories used to line them was identified by industry as a limitation to their reliability and availability and to their increased use. NETL researchers have examined spent high-Cr2O3 (over 90 pct Cr2O3) refractories from numerous gasifiers to determine in-service failure mechanisms. This analysis revealed that premature failure of the high chrome oxide refractories was related to ash in the carbon feedstock, which liquefies during gasification and interacts with the refractories, leading to wear by chemical dissolution or spalling (structural and chemical). A discussion of this postmortem wear of spent refractory materials and of thermodynamic modeling used to explain microstructural changes leading to wear are explained in this article. This information will serve the basis to develop improved performance refractory materials.

  7. Low SO2 emission from CFB co-firing MSW and bituminous.

    Science.gov (United States)

    Lu, Qing-Gang; Li, Zhi-Wei; Na, Yong-Jie; Ba, Shao-Lin; Sun, Yun-Kai; He, Jun

    2004-01-01

    Influence of co-firing rate on SO2 emission from co-firing municipal solid waste (MSW) and bituminous containing high amount of sulfur (1.79%) was studied in a 0.15 MWt circulating fluidized bed (CFB). The temperature selected is 1123 K, typical for MSW incineration using CFB. The particle concentration in the dilution zone of the furnace, the alkali metal concentration and sulfate concentration in the recirculating ash and fly ash, and flue gas composition were determined. The results showed that the addition of MSW leads to a significant decrease in SO2 emission. Concentration of SO2 in flue gas decreased to 0 with the co-firing rate greater than 51%. This reduction in SO2 emission is attributed both to the high particle concentration in the dilution zone of the furnace, the high content of alkali metals in the bed material, and to the comparatively high concentration of HCI in flue gas during co-firing of MSW and bituminous. PMID:15559820

  8. The Effect of Oxygen Staging on Nitrogen Conversion in Oxy-Fuel CFB Environment

    Directory of Open Access Journals (Sweden)

    Jankowska Sylwia

    2014-12-01

    Full Text Available This paper presents a study on nitrogen conversion in oxy-fuel coal combustion in a pilot scale CFB 0.1 MWth facility. The paper is focused on fuel-N behaviour in the combustion chamber when the combustion process is accomplished under oxy-fuel CFB conditions. The analysis is based on infurnace sampling of flue gas and calculations of the conversion ratios of fuel-nitrogen (fuel-N to NO, NO2, N2O, NH3 and HCN. For the tests, O2/CO2 mixtures with the oxygen content of 21 vol.% (primary gas and with the oxygen content varied from 21 to 35 vol.% (secondary gas, were used as the fluidising gas. Measurements were carried out in 4 control points located along the combustion chamber: 0.43 m, 1.45 m, 2.50 m and 4.88 m. Results presented below indicate that an increased oxygen concentration in the higher part of the combustion chamber has strong influence on the behaviour of fuel based nitrogen compounds.

  9. Mass balance performance of a 300 MW CFB boiler burning blend fuel with different mixing ratio

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yang; Chao, Junnan; Yang, Hairui; Lv, Junfu; Zhang, Hai; Liu, Qing; Yue, Guangxi [Tsinghua Univ., Beijing (China). Dept. of Thermal Engineering; Ministry of Education, Beijing (China). Key Lab. for Thermal Science and Power Engineering

    2013-07-01

    In order to predict the mass balance of a 300 MWe circulating fluidized bed (CFB) boiler under design process, the ash formation and attrition characteristic of the design fuel mixed with gangue, middling and slime were investigated with Tsinghua own process. In addition, the mass balance in this CFB boiler was simulated with 1D mass balance model, giving the ratio of the ashes, particle size distribution of circulating solid materials and solid circulating rat, Gs. By comparing the residence time distribution and the burn out time required for different size, the minimum bed pressure drop (BPD) or bed inventory in the furnace was determined for different mixing ratio among the three coals. The results show that under each mixing ratio, the solid circulating flux and solid suspension density in the upper furnace can meet the requirement of heating transfer. However, the minimum BPD or bed inventory required to meet the burn out time of the coarse solids was different. For in the case with the ratio among gangue, middling and slime as 5:3:2, the lowest value is 12 kPa, which will cause serious erosion and more power consumption. Because the middling has lower ash content, higher reactivity and better ash formation, increasing the proportion of the middling (1:5:4) will decrease the BPD greatly to 5 kPa, not only meet the requirements of material balance and burn time for coarse solids easily, but also realize the energy saving operation.

  10. Co-Combustion of Refuse Derived Fuel with Anthracites in a CFB Boiler

    Science.gov (United States)

    Kim, Dong-Won; Lee, Jong-Min; Kim, Jae-Sung

    Combustion of Refuse derived fuel (RDF) is considered as a priority solution to energy recovery from municipal solid waste (MSW). The co-combustion characteristics of anthracite coals with RDF were determined in the commercial scale Tonghae CFB Power Plant. As the feeding ratio of the RDF to the anthracites increased to 5%, temperature and pressure were not changed in comparison with firing only anthracites. The amount of the required air was reduced due to high O2 content in RDF relative to the anthracites. The emissions of NOx, SOx, HCl and Dioxin were also measured. According to higher mixing ratio of the RDF to the anthracites, SOx, NOx emissions slightly decreased and HCl emissions increased, because RDF has relatively smaller S, N and higher CI than the anthracites. Heavy metals of the fly ash and bottom ash and the dioxin emissions were far below Korean maximum permissible concentration level at incinerator. The results showed that it is of great use and technically possible to co-combustion of RDF with the anthracites by 5% in the form of fuel recovery and energy production in commercial scale CFB boiler.

  11. Study on Microstructure and Slag Corrosion Mechanism of High Chrome Bricks for Gasifier

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Research was focused on slag corrosion mechanism of high chrome bricks used for different types of gasifier by comparing the structure of high chrome bricks for petroleum coke gasifier and water-coal slurry gasifier with slag corroded testing brick and water coal slurry gasifier through Scanning Electron Microscope (SEM) examination and X-ray diffraction. Results show that for high chrome brick used for petroleum coke gasifier, corrosion is mainly caused by Cr2O3 in the brick and V2O5 in molten slag and liquid phase generation at low temperature; for high chrome brick used for water-coal slurry gasifier, corrosion is caused by dissolution of Cr2O3 in molten slag and corrosion of ZrO2. For LIRR-HK95 brick, it performs better petroleum coke corrosion resistance than the others due to the optimal composition and structure.

  12. LaMnAl11O19催化剂上生物质气化气燃烧中NH3-NOx的转化特性%Conversion of NH3-NOx in gasified biomass over LaMnAl11 O19 catalyst

    Institute of Scientific and Technical Information of China (English)

    彭丹; 孙路石; 王志远; 孔继红; 向军; 胡松; 苏胜

    2011-01-01

    采用共沉淀法制备了LaMnAl11O19六铝酸盐催化剂,采用XRD、BET和XPS对样品结构进行了表征,并通过模拟生物质气化气的燃烧实验和NH3单独氧化实验,分别考察了催化燃烧和均相燃烧过程中NH3的转化特性.利用原位漫反射红外光谱(in-situ DRIFT)法在线研究了NH3在催化剂表面的吸附和氧化信息.结果表明,焙烧后催化剂形成磁铅石(MP)结构的六铝酸盐晶体,且具有较大的比表面积,Mn以+2、+3价形式存在晶体中.均相燃烧下模拟气中的NH3在500℃开始反应,随之就有NO生成.催化燃烧工况下NH3氧化曲线和模拟气中NH3的转化曲线相差不大,NH3的起燃温度为310℃,反应后随之就有NO生成,NO在350℃~800℃保持一个较高的浓度.NO2的生成温度较高,并仅在较窄的温度区间内出现,在整个燃烧过程中仅检测到几个10-6的N2O,反应过程中有40%以上的NH3转化成NO.DRIFT结果表明,催化剂作用下NH3的转化遵循-NH反应机理,即催化剂表面吸附的NH3分解产生-NH,-NH与氧原子(O)反应生成HNO,再进一步反应生成N2或N2O,或是-NH直接与氧分子(O2)反应生成NO.%LaMnAl1,O19 catalysts were prepared by co-precipitation method and characterized with XRD, BET and XPS. The conversion of NH3 at the conditions of catalytic combustion and homogeneous combustion were studied by combustion of simulated biomass gasification gas and NH3 oxidation, respectively. Moreover, the NH3 adsorption and oxidation on the surfaces of the catalyst samples were examined by in-situ DRIFT experiments. It was found that calcination of the percursors at 1 200℃ led to the formation of a final monophasic materials with MP structure and high surface area, while the Mn ions were either divalent or trivalent. Under homogeneous combustion condition, NH3 at simulated biomass gasification gas started to react at 500℃, then NO was formed. Under catalytic combustion condition, the curves of NH3 oxidation with

  13. Biomass fuelled trigeneration system in selected buildings

    International Nuclear Information System (INIS)

    Highlights: → We model a commercial building scale biomass fuelled trigeneration plant. → It is economically feasible to use willow chips, miscanthus and rice husk as the fuel to operate the trigeneration system. → The efficiency of TG is much higher than that of PO, but is lower than that of the combined heat and power (CHP) configuration. → The breakeven electricity selling price (BESP) of the TG system is better than that of the PO option with the CHP option producing the cheapest electricity. -- Abstract: Many buildings require simultaneous electricity, heating and cooling. Biomass is one of the renewable energy sources which is not intermittent, location-dependent or very difficult to store. If grown sustainably, biomass can be considered to be CO2 neutral. A trigeneration system consisting of an internal combustion (IC) engine integrated with biomass gasification may offer a combination for delivering heat, electricity and cooling cleanly and economically. The producer gas generated by the gasifier is used to provide electricity for building use via the IC engine. The waste heat is recovered from the engine cooling system and exhaust gases to supply hot water to space heating, excess heat is also used to drive an absorption cooling system. The proposed system is designed to meet the energy requirements for selected commercial buildings and district heating/cooling applications. This work focuses on the modeling and simulation of a commercial building scale trigeneration plant fuelled by a biomass downdraft gasifier. In order to use both energy and financial resources most efficiently, technical and economic analyses were carried out, using the ECLIPSE process simulation package. The study also looks at the impact of different biomass feedstock (willow, rice husk and miscanthus) on the performance of a trigeneration plant.

  14. Biomass fuelled trigeneration system in selected buildings

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Y., E-mail: y.huang@ulster.ac.u [Centre for Sustainable Technologies, School of Built Environment, University of Ulster, Newtownabbey, BT37 0QB (United Kingdom); Wang, Y.D. [The Sir Joseph Swan Institute for Energy Research, Newcastle University, Newcastle Upon Tyne, NE1 7RU (United Kingdom); Rezvani, S.; McIlveen-Wright, D.R.; Anderson, M.; Hewitt, N.J. [Centre for Sustainable Technologies, School of Built Environment, University of Ulster, Newtownabbey, BT37 0QB (United Kingdom)

    2011-06-15

    Highlights: {yields} We model a commercial building scale biomass fuelled trigeneration plant. {yields} It is economically feasible to use willow chips, miscanthus and rice husk as the fuel to operate the trigeneration system. {yields} The efficiency of TG is much higher than that of PO, but is lower than that of the combined heat and power (CHP) configuration. {yields} The breakeven electricity selling price (BESP) of the TG system is better than that of the PO option with the CHP option producing the cheapest electricity. -- Abstract: Many buildings require simultaneous electricity, heating and cooling. Biomass is one of the renewable energy sources which is not intermittent, location-dependent or very difficult to store. If grown sustainably, biomass can be considered to be CO{sub 2} neutral. A trigeneration system consisting of an internal combustion (IC) engine integrated with biomass gasification may offer a combination for delivering heat, electricity and cooling cleanly and economically. The producer gas generated by the gasifier is used to provide electricity for building use via the IC engine. The waste heat is recovered from the engine cooling system and exhaust gases to supply hot water to space heating, excess heat is also used to drive an absorption cooling system. The proposed system is designed to meet the energy requirements for selected commercial buildings and district heating/cooling applications. This work focuses on the modeling and simulation of a commercial building scale trigeneration plant fuelled by a biomass downdraft gasifier. In order to use both energy and financial resources most efficiently, technical and economic analyses were carried out, using the ECLIPSE process simulation package. The study also looks at the impact of different biomass feedstock (willow, rice husk and miscanthus) on the performance of a trigeneration plant.

  15. 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 ...

  16. Analytical Investigations of Kinetic and Heat Transfer in Slow Pyrolysis of a Biomass Particle

    OpenAIRE

    S.J Ojolo; C.A. Osheku; M.G Sobamowo

    2013-01-01

    The utilization of biomass for heat and power generation has aroused the interest of most researchers especially those of energy .In converting solid fuel to a usable form of energy,pyrolysis plays an integral role. Understanding this very important phenomenon in the thermochemical conversion processes and representing it with appropriate mathematical models is vital in the design of pyrolysis reactors and biomass gasifiers. Therefore, this study presents analytical solutions to the kinetic a...

  17. Simulation of co-firing coal and biomass in circulating fluidized beds

    International Nuclear Information System (INIS)

    Highlights: ► The effect of the biomass share on CO, NOx and SO2 emissions are investigated. ► New model shows similar emissions trends for co-firing to industrial data. ► Biomass share has a positive effect on lowering the emissions in co-firing. - Abstract: In this study, the effect of the biomass share on CO, NOx and SO2 emissions are investigated to reveal the benefits of co-firing biomass and coal in CFBs by using a developed model. The results are compared with two published comprehensive data sets. The results show that CO, NOx and SO2 emissions decrease as the biomass share increases for industrial scale CFB combustors.

  18. Biomass pretreatment

    Science.gov (United States)

    Hennessey, Susan Marie; Friend, Julie; Elander, Richard T; Tucker, III, Melvin P

    2013-05-21

    A method is provided for producing an improved pretreated biomass product for use in saccharification followed by fermentation to produce a target chemical that includes removal of saccharification and or fermentation inhibitors from the pretreated biomass product. Specifically, the pretreated biomass product derived from using the present method has fewer inhibitors of saccharification and/or fermentation without a loss in sugar content.

  19. Economic analysis of a 20 kW gasifier; Analise economica de um gaseificador de 20 kW

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Marcos Vinicius Miranda da; Rocha, Brigida Ramati Pereira da [Universidade Federal do Para (NEDS/UFPA), Belem, PA (Brazil). Nucleo de Energia para o Desenvolvimento Sustentavel], e-mail: neds@ufpa.br

    2006-07-01

    The gasification of biomass residues has been pointed as an alternative in electricity supplying for small communities of the Amazon region, because it promotes a significant substitution of the diesel oil in the electric power generation. This paper presents an economic analysis of an electricity generation system (gasifier and generator set) of 20 kw that is installed in the community of Jenipauba, in the State of Para. That analysis confirms the economic attractiveness of that energy alternative on the generator sets that operate exclusively with diesel oil. It also shows the impact of the labor law on electricity generation cost, as well as the need of subsidizing the electric power generation, because the community of Jenipauba is very poor. (author)

  20. Simultaneous carbonation and sulfation of CaO in Oxy-Fuel CFB combustion

    Energy Technology Data Exchange (ETDEWEB)

    Wang, C. [School of Energy and Power Engineering, North China Electric Power University, Baoding City, Hebei Province (China); Jia, L.; Tan, Y. [CanmetENERGY, 1 Haanel Drive, Ottawa, Ontario, K1A 1M1 (Canada)

    2011-10-15

    For anthracites and petroleum cokes, the typical combustion temperature in a circulating fluidized bed (CFB) is > 900 C. At CO{sub 2} concentrations of 80-85 % (typical of oxy-fuel CFBC conditions), limestone still calcines. When the ash which includes unreacted CaO cools to the calcination temperature, carbonation of fly ash deposited on cool surfaces may occur. At the same time, indirect and direct sulfation of limestone also will occur, possibly leading to more deposition. In this study, CaO was carbonated and sulfated simultaneously in a thermogravimetric analyzer (TGA) under conditions expected in an oxy-fuel CFBC. It was found that temperature, and concentrations of CO{sub 2}, SO{sub 2}, and especially H{sub 2}O are important factors in determining the carbonation/sulfation reactions of CaO. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. 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.

  2. Optical Fiber Sensor Instrumentation for Slagging Coal Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Anbo Wang; Kristie Cooper

    2008-07-19

    Coal gasifier is one of the most promising solutions for clean fossil energy. Refractory thickness monitoring and online real-time temperature measurement is needed for improved reliability and advanced process control for current and future generation power plants. The objective of this program is to design and implement an optical fiber based sensing system that could potentially be used to monitor refractory wall thickness and temperature inside a coal gasifier. For the thickness monitoring, the system should be able to operate at temperatures up to 1000 C. For this temperature range, silica fiber can still work so it is chosen for the sensor design. The measurement is based on a photon counting optical time domain reflectometer. A narrow light pulse is launched into a silica fiber which could be embedded into the gasifier refractory wall, and is partially reflected by the far end of the fiber. The time of flight of the light pulse in the fiber then gives an indication of the position of the fiber end, which is a function of the wall thickness when the fiber is embedded. Results obtained show a measurement accuracy of {+-}2cm in environment of 1000 C with a saw cut fiber end. When the fiber end is corroded by sodium carbide at 900 C, the accuracy is {+-}3cm. For the temperature measurement, a single crystal sapphire fiber sensor is designed. The sapphire fiber guides the broadband light from a light emitting diode to a sapphire wafer functioning as a Fabry-Perot interferometer and the wafer optical thickness is a function of temperature. The returned optical signal is then demodulated by multimode fiber based whitelight interferometry. The system was tested up to 1500 C with a measurement accuracy of {+-}10 C for the entire measurement range.

  3. Efficiency tests on the pyrolysis gasifier stove Peko Pe

    DEFF Research Database (Denmark)

    Nielsen, Per Sieverts

    1996-01-01

    This paper presents results from water boiling tests on the pyrolysis gasifier stove Peko Pe, which has been developed by the Norwegian Paal Wendelbo. The stove efficiency determined vary between 21 and 29% when burning dry Danish woodchips (10% moisture) with an estimated caloric value of 16 MJ...... the water content in the grass. In Adjumani refugee camp it was furthermore found that the stove was able to provide sufficient energy from solid combustion, after the pyrolysis was stopped, to boil water for additional 25-30 minutes with lid. This effect was not seen in the tests on woodchips in...

  4. 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.

  5. Biomass recalcitrance

    DEFF Research Database (Denmark)

    Felby, Claus

    2009-01-01

    Alternative and renewable fuels derived from lignocellulosic biomass offer a promising alternative to conventional energy sources, and provide energy security, economic growth, and environmental benefits. However, plant cell walls naturally resist decomposition from microbes and enzymes - this co......Alternative and renewable fuels derived from lignocellulosic biomass offer a promising alternative to conventional energy sources, and provide energy security, economic growth, and environmental benefits. However, plant cell walls naturally resist decomposition from microbes and enzymes......, enzymatic hydrolysis, and product fermentation options. Biomass Recalcitrance is essential reading for researchers, process chemists and engineers working in biomass conversion, also plant scientists working in cell wall biology and plant biotechnology. This book examines the connection between biomass...... of plant cell wall structure, chemical treatments, enzymatic hydrolysis, and product fermentation options. "Biomass Recalcitrance" is essential reading for researchers, process chemists and engineers working in biomass conversion, also plant scientists working in cell wall biology and plant biotechnology....

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-12-11

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-09-30

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

  8. LIQUID BIO-FUEL PRODUCTION FROM NON-FOOD BIOMASS VIA HIGH TEMPERATURE STEAM ELECTROLYSIS

    Energy Technology Data Exchange (ETDEWEB)

    G. L. Hawkes; J. E. O' Brien; M. G. McKellar

    2011-11-01

    Bio-Syntrolysis is a hybrid energy process that enables production of synthetic liquid fuels that are compatible with the existing conventional liquid transportation fuels infrastructure. Using biomass as a renewable carbon source, and supplemental hydrogen from high-temperature steam electrolysis (HTSE), bio-syntrolysis has the potential to provide a significant alternative petroleum source that could reduce US dependence on imported oil. Combining hydrogen from HTSE with CO from an oxygen-blown biomass gasifier yields syngas to be used as a feedstock for synthesis of liquid transportation fuels via a Fischer-Tropsch process. Conversion of syngas to liquid hydrocarbon fuels, using a biomass-based carbon source, expands the application of renewable energy beyond the grid to include transportation fuels. It can also contribute to grid stability associated with non-dispatchable power generation. The use of supplemental hydrogen from HTSE enables greater than 90% utilization of the biomass carbon content which is about 2.5 times higher than carbon utilization associated with traditional cellulosic ethanol production. If the electrical power source needed for HTSE is based on nuclear or renewable energy, the process is carbon neutral. INL has demonstrated improved biomass processing prior to gasification. Recyclable biomass in the form of crop residue or energy crops would serve as the feedstock for this process. A process model of syngas production using high temperature electrolysis and biomass gasification is presented. Process heat from the biomass gasifier is used to heat steam for the hydrogen production via the high temperature steam electrolysis process. Oxygen produced form the electrolysis process is used to control the oxidation rate in the oxygen-blown biomass gasifier. Based on the gasifier temperature, 94% to 95% of the carbon in the biomass becomes carbon monoxide in the syngas (carbon monoxide and hydrogen). Assuming the thermal efficiency of the power

  9. CALLA ENERGY BIOMASS COFIRING PROJECT

    International Nuclear Information System (INIS)

    The Calla Energy Biomass Project, to be located in Estill County, Kentucky is to be conducted in two phases. The objective of Phase I is to evaluate the technical and economic feasibility of cofiring biomass-based gasification fuel-gas in a power generation boiler. Waste coal fines are to be evaluated as the cofired fuel. The project is based on the use of commercially available technology for feeding and gas cleanup that would be suitable for deployment in municipal, large industrial and utility applications. Define a combustion system for the biomass gasification-based fuel-gas capable of stable, low-NOx combustion over the full range of gaseous fuel mixtures, with low carbon monoxide emissions and turndown capabilities suitable for large-scale power generation applications. The objective for Phase II is to design, install and demonstrate the combined gasification and combustion system in a large-scale, long-term cofiring operation to promote acceptance and utilization of indirect biomass cofiring technology for large-scale power generation applications. During this Performance Period work efforts proceeded, and Carbona completed the gasifier island design package. Nexant has completed the balance of plant support systems design and the design for the biomass feed system. Work on the Technoeconomic Study is proceeding. Approximately 75% of the specified hardware quotations have been received at the end of the reporting period. A meeting is scheduled for July 23 rd and 24 th to review the preliminary cost estimates. GTI presented a status review update of the project at the DOE/NETL contractor's review meeting in Pittsburgh on June 21st

  10. Preparation of gasification feedstock from leafy biomass.

    Science.gov (United States)

    Shone, C M; Jothi, T J S

    2016-05-01

    Dried leaves are a potential source of energy although these are not commonly used beside to satisfy daily energy demands in rural areas. This paper aims at preparing a leafy biomass feedstock in the form of briquettes which can be directly used for combustion or to extract the combustible gas using a gasifier. Teak (Tectona grandis) and rubber (Hevea brasiliensis) leaves are considered for the present study. A binder-assisted briquetting technique with tapioca starch as binder is adopted. Properties of these leafy biomass briquettes such as moisture content, calorific value, compressive strength, and shatter index are determined. From the study, briquettes with biomass-to-binder ratio of 3:5 are found to be stable. Higher mass percentage of binder is considered for preparation of briquettes due to the fact that leafy biomasses do not adhere well on densification with lower binder content. Ultimate analysis test is conducted to analyze the gasification potential of the briquettes. Results show that the leafy biomass prepared from teak and rubber leaves has calorific values of 17.5 and 17.8 MJ/kg, respectively, which are comparable with those of existing biomass feedstock made of sawdust, rice husk, and rice straw. PMID:26289326

  11. Experiment research on two-stage dry-fed entrained flow coal gasifier

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The process flow and the main devices of a new two-stage dry-fed coal gasification pilot plant with a throughout of 36 t/d are introduced in this paper. For comparison with the traditional one-stage gasifiers, the influences of the coal feed ratio between two stages on the performance of the gasifier are detailedly studied by a series of experiments. The results reveal that the two-stage gasification decreases the temperature of the syngas at the outlet of the gasifier, simplifies the gasification process, and reduces the size of the syngas cooler. Moreover, the cold gas efficiency of the gasifier can be improved by using the two-stage gasification. In our experiments, the efficiency is about 3%-6% higher than the existing one-stage gasifiers.

  12. Apparatus, components and operating methods for circulating fluidized bed transport gasifiers and reactors

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-02-24

    The improvements proposed in this invention provide a reliable apparatus and method to gasify low rank coals in a class of pressurized circulating fluidized bed reactors termed "transport gasifier." The embodiments overcome a number of operability and reliability problems with existing gasifiers. The systems and methods address issues related to distribution of gasification agent without the use of internals, management of heat release to avoid any agglomeration and clinker formation, specific design of bends to withstand the highly erosive environment due to high solid particles circulation rates, design of a standpipe cyclone to withstand high temperature gasification environment, compact design of seal-leg that can handle high mass solids flux, design of nozzles that eliminate plugging, uniform aeration of large diameter Standpipe, oxidant injection at the cyclone exits to effectively modulate gasifier exit temperature and reduction in overall height of the gasifier with a modified non-mechanical valve.

  13. Advanced coal gasifier-fuel cell power plant systems design

    Science.gov (United States)

    Heller, M. E.

    1983-01-01

    Two advanced, high efficiency coal-fired power plants were designed, one utilizing a phosphoric acid fuel cell and one utilizing a molten carbonate fuel cell. Both incorporate a TRW Catalytic Hydrogen Process gasifier and regenerator. Both plants operate without an oxygen plant and without requiring water feed; they, instead, require makeup dolomite. Neither plant requires a shift converter; neither plant has heat exchangers operating above 1250 F. Both plants have attractive efficiencies and costs. While the molten carbonate version has a higher (52%) efficiency than the phosphoric acid version (48%), it also has a higher ($0.078/kWh versus $0.072/kWh) ten-year levelized cost of electricity. The phosphoric acid fuel cell power plant is probably feasible to build in the near term: questions about the TRW process need to be answered experimentally, such as weather it can operate on caking coals, and how effective the catalyzed carbon-dioxide acceptor will be at pilot scale, both in removing carbon dioxide and in removing sulfur from the gasifier.

  14. 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)

  15. Evaluation of reduced kinetics in simulation of gasified biomass gas combustion

    OpenAIRE

    ZHANG, Xiaoxiang; Jayasuriya, Jeevan; Fakhraie, Reza; Fransson, Torsten

    2013-01-01

    It is essentially important to use appropriate chemical kinetic models in the simulation process of gas turbine combustion. To integrate the detailed kinetics into complex combustion simulations has proven to be a computationally expensive task with tens to thousands of elementary reaction steps. It has been suggested that an appropriate simplified kinetics which are computationally efficient could be used instead. Therefore reduced kinetics are often used in CFD simulation of gas turbine com...

  16. Techno-economic assessment of FT unit for synthetic diesel production in existing stand-alone biomass gasification plant using process simulation tool

    DEFF Research Database (Denmark)

    Hunpinyo, Piyapong; Narataruksa, Phavanee; Tungkamani, Sabaithip; Chollacoop, Nuwong; Cheali, Peam

    2014-01-01

    For alternative thermo-chemical conversion process route via gasification, biomass can be gasified to produce syngas (mainly CO and H2). On more applications of utilization, syngas can be used to synthesize fuels through the catalytic process option for producing synthetic liquid fuels such as...... Fischer-Tropsch (FT) diesel. The embedding of the FT plant into the stand-alone based on power mode plants for production of a synthetic fuel is a promising practice, which requires an extensive adaptation of conventional techniques to the special chemical needs found in a gasified biomass. Because there...

  17. Biomass granular screw feeding: An experimental investigation

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Jianjun; Grace, John R. [Department of Chemical and Biological Engineering, University of British Columbia, 2360 East Mall, Vancouver, BC, V6 T 1Z3 (Canada)

    2011-02-15

    Successful feeding is critical to biomass utilization processes, but difficult due to the heterogeneity, physical properties and moisture content of the particles. The objectives of the present study were to find the mechanisms of blockage in screw feeding and to determine the effects of particle mean size (0.5-15 mm), size distribution, shape, moisture content (10-60%), density and compressibility on biomass particle feeding at room temperature. Wood pellets, sawdust, hog fuel and wood shavings were tested in a screw feeder/lock hopper system previously employed to feed sawdust into a pilot-scale circulating fluidized-bed gasifier. Experimental results showed that large particles, wide size distributions, large bulk densities and high moisture contents generally led to larger torque requirements for screw feeding. The ''choke section'' and seal plug play important roles in determining the torque requirements. (author)

  18. 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)

  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. Status of external firing of biomass in gas turbines

    Energy Technology Data Exchange (ETDEWEB)

    Bram, S.; De Ruyck, J.; Novak Zdravkovic, A.

    2005-02-15

    Dry biomass can be used as a fuel for gas turbines in different ways: it can be gasified or pyrolysed for internal combustion or it can be used as an external heat source. This heat source can be used to replace the combustor, to preheat the combustion air, or eventually to feed a primary reformer to yield hydrogen for the gas turbine. The present paper discusses the use of biomass as on external heat source from both a technical and an economic point of view. Past, present, and future projects are discussed. Possibilities range from cogeneration with microturbines where the biomass can cover a major part of the primary energy, to combined cycle plants where biomass can replace a small percentage of the natural gas. A microturbine EFGT project under construction is disclosed. (Author)

  1. Synthesis of methanol from biomass/CO{sub 2} resources

    Energy Technology Data Exchange (ETDEWEB)

    Specht, M.; Bandi, A.; Baumgart, F. [Center for Solar Energy and Hydrogen Research (ZSW), Stuttgart (Germany); Murray, C.N. [Joint Research Centre, Environment Inst., Ispra (Italy); Gretz, J. [Hydrogen Association, Hamburg (Germany)

    1999-07-01

    The utilisation of biomass for methanol production via gasification faces the problem of a large excess carbon in the produced synthesis gas. The stoichiometric adjustment can be accomplished either by adding hydrogen or by removing carbon in form of carbon dioxide. The addition of hydrogen allows a nearly complete utilisation of the carbon contained in the biomass, with a high methanol production rate. But hydrogen admixture to the syngas requires supplementary investments for an electrolysis unit. The removal of carbon dioxide is less investment intensive, but due to the extremely low carbon conversion efficiency of about 20% of the biomass carbon content, the methanol production costs become very high. An acceptable way is a partial compensation of the carbon excess by adding electrolytic hydrogen (using the oxygen for the gasifying process), saving about half of the carbon from the biomass and avoiding extremely high investment and electricity costs. (Author)

  2. Synthesis of methanol from biomass/CO2 resources

    International Nuclear Information System (INIS)

    The utilisation of biomass for methanol production via gasification faces the problem of a large excess carbon in the produced synthesis gas. The stoichiometric adjustment can be accomplished either by adding hydrogen or by removing carbon in form of carbon dioxide. The addition of hydrogen allows a nearly complete utilisation of the carbon contained in the biomass, with a high methanol production rate. But hydrogen admixture to the syngas requires supplementary investments for an electrolysis unit. The removal of carbon dioxide is less investment intensive, but due to the extremely low carbon conversion efficiency of about 20% of the biomass carbon content, the methanol production costs become very high. An acceptable way is a partial compensation of the carbon excess by adding electrolytic hydrogen (using the oxygen for the gasifying process), saving about half of the carbon from the biomass and avoiding extremely high investment and electricity costs. (Author)

  3. Numerical analysis of flow instability in the water wall of a supercritical CFB boiler with annular furnace

    Science.gov (United States)

    Xie, Beibei; Yang, Dong; Xie, Haiyan; Nie, Xin; Liu, Wanyu

    2016-08-01

    In order to expand the study on flow instability of supercritical circulating fluidized bed (CFB) boiler, a new numerical computational model considering the heat storage of the tube wall metal was presented in this paper. The lumped parameter method was proposed for wall temperature calculation and the single channel model was adopted for the analysis of flow instability. Based on the time-domain method, a new numerical computational program suitable for the analysis of flow instability in the water wall of supercritical CFB boiler with annular furnace was established. To verify the code, calculation results were respectively compared with data of commercial software. According to the comparisons, the new code was proved to be reasonable and accurate for practical engineering application in analysis of flow instability. Based on the new program, the flow instability of supercritical CFB boiler with annular furnace was simulated by time-domain method. When 1.2 times heat load disturbance was applied on the loop, results showed that the inlet flow rate, outlet flow rate and wall temperature fluctuated with time eventually remained at constant values, suggesting that the hydrodynamic flow was stable. The results also showed that in the case of considering the heat storage, the flow in the water wall is easier to return to stable state than without considering heat storage.

  4. Measurement of gas-solid flow pattern in rectangle cross-section in CFB by electrical capacitance tomography

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jingji; Wang, Wei; Yang, Hairui; Zhang, Hai; Liu, Qing [Tsinghua Univ., Beijing (China). Dept. of Thermal Engineering; Ministry of Education, Beijing (China). Key Lab. for Thermal Science and Power Engineering

    2013-07-01

    The mal-distribution of solid suspension density in the circulating fluidized bed (CFB) boiler with parallel cyclones is a hot research topic recently. The measurement of gas-solid flow characteristics, including the solid concentration distribution and the velocity profile, is the key to understand such phoneme. Comparing with other measuring methods, such as PIV, LDV, {gamma}-ray attenuation technology, the electrical capacitance tomography (ECT) technology has the features of online monitoring, non-invasive, safe and economically. So far, in most of the studies with ECT measurements, the sensors have circular or square section, which cannot measure the gas flow directly in the rectangle section commonly used in CFB boiler furnace. Based on the circular section sensor, by modifying the signal acquisition and image reconstruction, an ECT sensor with rectangular section and 8 electrodes was designed and manufactured, which was used to investigate the gas solid flow in a CFB riser with rectangle section (300 mm 80 mm). Meanwhile, the optical fiber probe was employed to measure the particle velocity and the thickness of boundary layer. The results prove that the ECT sensor with rectangle section can acquire the gas-solid flow characteristics.

  5. 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

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

    Directory of Open Access Journals (Sweden)

    Ping Wang

    2013-02-01

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

  7. Release of chlorine from biomass at gasification conditions

    International Nuclear Information System (INIS)

    The objective of the project was to investigate the influence of different gasifying atmospheres on the release of chlorine from biomass during gasification conditions. Furthermore, the purpose was also to try and identify the formed chloro compounds. The results showed that O2, H2O and CO2 had negligible effect on the chlorine release at temperatures under 700 deg C. At temperatures above 800 deg C the reactivity towards CO2 increased and could be seen as higher chlorine release and less solid residue. No chloro organic compounds (aliphatic one to six carbons or aromatic one to two rings) could be detected in the tar or the fuel gas produced during pyrolysis/gasifying. On the other hand, comparable amounts of chlorinated benzenes were found in the cooling section during combustion of lucerne and of synthetic waste, indicating that oxygen is essential for chlorination reactions. 11 refs, 4 figs, 1 tab

  8. CO-FIRING COAL: FEEDLOT AND LITTER BIOMASS FUELS

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2002-03-31

    Proposed activities for quarter 7 (12/15/01-3/14/2002): (1) Incorporation of moisture model into PCGC2 code. Parametric study of moisture effects on flame structure and pollutants emissions in cofiring of coal and Liter Biomass (LB) (Task 4); (2) Use the ash tracer method to determine the combustion efficiency and comparison it to results from gas analysis (Task 2); (3) Effect of swirl on combustion performance (Task 2); (4) Completion of the proposed modifications to the gasifier setup (Task 3); (5) Calibration of the Gas Chromatograph (GC) used for measuring the product gas species (Task 3); and (6) To obtain temperature profiles for different fuels under different operating conditions in the fixed bed gasifier (Task 3).

  9. CO-FIRING COAL: FEEDLOT AND LITTER BIOMASS FUELS

    International Nuclear Information System (INIS)

    Proposed activities for quarter 7 (12/15/01-3/14/2002): (1) Incorporation of moisture model into PCGC2 code. Parametric study of moisture effects on flame structure and pollutants emissions in cofiring of coal and Liter Biomass (LB) (Task 4); (2) Use the ash tracer method to determine the combustion efficiency and comparison it to results from gas analysis (Task 2); (3) Effect of swirl on combustion performance (Task 2); (4) Completion of the proposed modifications to the gasifier setup (Task 3); (5) Calibration of the Gas Chromatograph (GC) used for measuring the product gas species (Task 3); and (6) To obtain temperature profiles for different fuels under different operating conditions in the fixed bed gasifier (Task 3)

  10. Test of pyrolysis gasifier stoves in two institutional kitchens in Uganda

    DEFF Research Database (Denmark)

    Wendelbo, Pall; Nielsen, Per Sieverts

    1998-01-01

    : The main purpose of the paper is to evaluate tests of institutional kitchens carried out at schools in Uganda 1997. The results of the tests for the institutional kitchen with pyrolysis gasifier stoves are compared with the fuel use in traditional kitchens with three-stone stoves. The project was...... financed by the Norwegian Forestry Society and involved two institutional kitchens in the northern part of Uganda. The pyrolysis gasifier stove, which is used as heating source, is a simple batch feeded top-down inverted gasifier. The two institutional kitchens prepared food for 107 students and 700 pupils...

  11. 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

  12. 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

  13. Effect of sewage sludge content on gas quality and solid residues produced by cogasification in an updraft gasifier

    International Nuclear Information System (INIS)

    Highlights: ► Cogasification of sewage sludge with wood pellets in updraft gasifier was analysed. ► The effects of sewage sludge content on the gasification process were examined. ► Sewage sludge addition up to 30 wt.% reduces moderately the process performance. ► At high sewage sludge content slagging and clinker formation occurred. ► Solid residues produced resulted acceptable at landfills for non-hazardous waste. - Abstract: In the present work, the gasification with air of dehydrated sewage sludge (SS) with 20 wt.% moisture mixed with conventional woody biomass was investigated using a pilot fixed-bed updraft gasifier. Attention was focused on the effect of the SS content on the gasification performance and on the environmental impact of the process. The results showed that it is possible to co-gasify SS with wood pellets (WPs) in updraft fixed-bed gasification installations. However, at high content of sewage sludge the gasification process can become instable because of the very high ash content and low ash fusion temperatures of SS. At an equivalent ratio of 0.25, compared with wood pellets gasification, the addition of sewage sludge led to a reduction of gas yield in favor of an increase of condensate production with consequent cold gas efficiency decrease. Low concentrations of dioxins/furans and PAHs were measured in the gas produced by SS gasification, well below the limiting values for the exhaust gaseous emissions. NH3, HCl and HF contents were very low because most of these compounds were retained in the wet scrubber systems. On the other hand, high H2S levels were measured due to high sulfur content of SS. Heavy metals supplied with the feedstocks were mostly retained in gasification solid residues. The leachability tests performed according to European regulations showed that metals leachability was within the limits for landfilling inert residues. On the other hand, sulfate and chloride releases were found to comply with the limits for

  14. Trigeneration integrated with absorption enhanced reforming of lignite and biomass

    Energy Technology Data Exchange (ETDEWEB)

    Yaodong Wang; Ye Huang; Anthony P. Roskilly [Newcastle University, Newcastle Upon Tyne (United Kingdom). Sir Joseph Swan Institute for Energy Research

    2009-10-15

    A technical investigation of an innovative trigeneration integrated with absorption enhanced reforming (AER) of lignite and biomass is carried out using the ECLIPSE process simulator. The system includes an internal combustion engine, an AER gasifier, a waste heat recovery and storage unit and an absorption refrigerator. The whole system is operated in the following sequence: The AER gasifier is used to generate hydrogen using lignite and biomass; the hydrogen generated is used to run the engine which drives a generator to produce electricity. Additionally, the heat recovery unit collects waste heat from the engine and is used to supply hot water and space heating. Furthermore, the waste heat is used to operate the absorption refrigerator. The electricity, heat and cooling can be used to meet the energy requirements for the households in a village, a resident building or a commercial building, or a supermarket. Within the study, the effects of lignite mixed with three different types of biomass (straw, willow and switch grass) on the system performance are investigated and the results are compared. The results show that it is feasible to use an AER system to reform the low quality fuels lignite and biomass to generate a cleaner fuel - hydrogen to replace fossil fuels (diesel or natural gas) and to fuel an engine based trigeneration system; the system works with high efficiencies and with a potential of carbon capture from the sorbent-regeneration process that would benefit the environment. 25 refs., 2 figs., 3 tabs.

  15. Influence of Partial Combustion on Rapid Pyrolysis of Wood Biomass

    Science.gov (United States)

    Yasuda, Hajime; Yamada, Osamu; Kaiho, Mamoru; Shinagawa, Takuya; Matsui, Satoshi; Iwasaki, Toshihiko; Shimada, Sohei

    A batch reactor was made and used in this work. In an actual rapid pyrolyzer/gasifier, each biomass is thrown into high temperature zone in the reactor. In order to simulate the reaction occurred in a fluidized bed rapid pyrolyzer/gasifier, the reactor was designed to inject samples into reaction zone directly and to control the reaction time optionally. Rapid pyrolysis of wood biomasses, such as Konara, bagasse, and EFB (Empty Fruit Bunch), was carried out at 1073K in nitrogen with the reaction time range of 2-20s. Difference in product distribution with varying reaction time was observed apparently among Konara, bagasse, and EFB. The difference in the reactivity among sorts of biomass should be considered even when their elemental composition and/or components ratio are similar. Rapid pyrolysis of wood biomass (Japanese cedar) with small amount of oxygen as gasification agent was also carried out. The amount of product gas was decreased through 1s to 2s and the decreasing rate was higher with increase in the amount of oxygen.

  16. Sensitivity study of fluid dynamic effects on nitric oxide formation in CFB combustion of wood

    Energy Technology Data Exchange (ETDEWEB)

    Kallio, S.; Kilpinen, P.; Konttinen, J. [Abo Akademi Univ., Turku (Finland); Leckner, B.; Armand, L.E. [Chalmers Univ. of Technology, Goteborg (Sweden)

    2002-07-01

    The type of fuel and operating conditions in circulating fluidized bed combustion (CFBC) can vary widely. Potential fuels include coals, biofuels and wastes. The use of biofuels as an energy source has stimulated much interest around the world, but the nitric oxide (NO) emissions from CFB combustion of wood is of the same order of magnitude as from combustion of coal with high N content. This paper presents a newly developed 1.5D numerical model that examines the formation of NO and nitrous oxide (N{sub 2}O) emissions in a CFBC under varying operating conditions and different fuel types. A comprehensive kinetic scheme was used for the homogeneous chemistry and a single particle model for char combustion. Gas mixing and release of volatiles were the fluid dynamic factors that were examined for wood combustion under normal air staging conditions. The formation of high NO emissions from wood burning was found to depend greatly on the pattern of volatile releases as well as the mixing of secondary air and gas. Nitric oxide was found to form higher in the riser during wood combustion compared to coal combustion. The large amount of char at the bottom of the bed is an important source of nitric oxide. 14 refs., 1 tab., 8 figs.

  17. Removal of heavy metals from wastewater using CFB-coal fly ash zeolitic materials

    International Nuclear Information System (INIS)

    Polish bituminous (PB) and South African (SA) coal fly ash (FA) samples, derived from pilot-scale circulated fluidized bed (CFB) combustion facilities, were utilized as raw materials for the synthesis of zeolitic products. The two FAs underwent a hydrothermal activation with 1 M NaOH solution. Two different FA/NaOH solution/ratios (50, 100 g/L) were applied for each sample and several zeolitic materials were formed. The experimental products were characterized by means of X-ray diffraction (XRD) and energy dispersive X-ray coupled-scanning electron microscope (EDX/SEM), while X-ray fluorescence (XRF) was applied for the determination of their chemical composition. The zeolitic products were also evaluated in terms of their cation exchange capacity (CEC), specific surface area (SSA), specific gravity (SG), particle size distribution (PSD), pH and the range of their micro- and macroporosity. Afterwards the hybrid materials were tested for their ability of adsorbing Cr, Pb, Ni, Cu, Cd and Zn from contaminated liquids. Main parameters for the precipitation of the heavy metals, as it was concluded from the experimental results, are the mineralogical composition of the initial fly ashes, as well as the type and the amount of the produced zeolite and specifically the mechanism by which the metals ions are hold on the substrate.

  18. Practical experience with the input/loss method as applied to a CFB power plant

    Energy Technology Data Exchange (ETDEWEB)

    Deihl, B.; Lang, F.D.

    1999-07-01

    In late 1995 the Input/Loss Method was installed for on-line monitoring of an independent power producer located in Colver, PA. Colver is a 115 MWe Circulating Fluidized Bed (CFB) steam generator burning poor quality coal, having typically {+-}20% variation in As-Fired heating value, providing considerable difficulties to operating staff. The Input/Loss Method provides a complete thermal understanding of a power plant through explicit determinations of fuel flow, emission flows, fuel chemistry, fuel heating value and thermal efficiency. Direct measurements of fuel or emission flows are not made. In addition, the Method employs a Fuel Consumption Index (FCI) technology to alert the operator as to which components/processes within the system have higher irreversible losses--in terms of higher fuel consumptions for a given power level--thus where improved heat rate can be found. The Method also uses a Sulfur Function Optimizer (SFO) parameter, which assist the operator in minimizing the use of limestone, while meeting regulatory SO{sub 2} effluents. This paper discusses a number of actual operational situations, taken over the past four years, which were resolved with the help of the Input/Loss Method. For example: the usefulness of the SFO parameter, tracking FCI for key processes, plant-evaluated economics, etc. Problems with required effluent (CEMS) instrumentation, experience with a CEMS error analysis procedure, stoichiometric assumptions, air leakage assumptions, etc. are discussed.

  19. The influence of attrition and cyclone performance on the particle size distribution in a CFB system

    Energy Technology Data Exchange (ETDEWEB)

    Cornelis Klett; Ernst-Ulrich Hartge; Joachim Werther [Technical University Hamburg-Harburg, Hamburg (Germany)

    2005-07-01

    Based on previous investigations in the authors' group on attrition mechanisms in fluidized bed systems a model has been developed which allows the simulation of the influences of particle attrition and cyclone performance on the time-dependent development of the particle size distribution in a circulating fluidized bed system consisting of a riser, a cyclone and a solids return leg. In an extension of previous work it was now possible to include the effect of the residence time of the particles in the system. The model takes account of the fact that fresh particles have a higher attrition rate than particles which have stayed for some time already in the system. The model is able to describe the dynamic adjustment of the particle size distribution in a given system. The model was validated with coal combustion experiments in a pilot-scale CFB combustion unit. Ash samples were taken from the bottom part of the riser and compared with the theoretical predictions. The model was used in simulation runs to study the effects of changes in the operating conditions on the steady-state solids particle size distribution and solids mass fluxes. 9 refs., 9 figs., 2 tabs.

  20. Biomass energy

    International Nuclear Information System (INIS)

    Bioenergy systems can provide an energy supply that is environmentally sound and sustainable, although, like all energy systems, they have an environmental impact. The impact often depends more on the way the whole system is managed than on the fuel or on the conversion technology. The authors first describe traditional biomass systems: combustion and deforestation; health impact; charcoal conversion; and agricultural residues. A discussion of modern biomass systems follows: biogas; producer gas; alcohol fuels; modern wood fuel resources; and modern biomass combustion. The issue of bioenergy and the environment (land use; air pollution; water; socioeconomic impacts) and a discussion of sustainable bioenergy use complete the paper. 53 refs., 9 figs., 14 tabs

  1. Modelling of a Biomass Gasification Plant Feeding a Hybrid Solid Oxide Fuel Cell and Micro Gas Turbine System

    DEFF Research Database (Denmark)

    Bang-Møller, Christian; Rokni, Masoud

    2009-01-01

    A system level modelling study on two combined heat and power (CHP) systems both based on biomass gasification. One system converts the product gas in a solid oxide fuel cell (SOFC) and the other in a combined SOFC and micro gas turbine (MGT) arrangement. An electrochemical model of the SOFC has...... been developed and calibrated against published data from Topsoe Fuel Cells A/S (TOFC) and Risø National Laboratory. The modelled gasifier is based on an up scaled version of the demonstrated low tar gasifier, Viking, situated at the Technical University of Denmark. The MGT utilizes the unconverted...

  2. Decentralized combined heat and power production by two-stage biomass gasification and solid oxide fuel cells

    DEFF Research Database (Denmark)

    Bang-Møller, Christian; Rokni, Masoud; Elmegaard, Brian;

    2013-01-01

    fuel cells (SOFC). Based on experimental data from a demonstrated 0.6 MWth two-stage gasifier, a model of the gasifier plant was developed and calibrated. Similarly, an SOFC model was developed using published experimental data. Simulation of a 3 MWth plant combining two-stage biomass gasification and...... SOFCs predicted a net electrical efficiency of 44.9% (LHV (lower heating value)) when 1.4 MWe power was produced. The work had significant focus on providing a highly accurate model of the complete plant. A sensitivity analysis revealed that the SOFC operating temperature, SOFC fuel utilization factor...

  3. Fresh tar (from biomass gasification) destruction with downstream catalysts: comparison of their intrinsic activity with a realistic kinetic model

    Energy Technology Data Exchange (ETDEWEB)

    Corella, J.; Narvaez, I.; Orio, A. [Complutense Univ. of Madrid (Spain). Dept. of Chemical Engineering

    1996-12-31

    A model for fresh tar destruction over catalysts placed downstream a biomass gasifier is presented. It includes the stoichio-metry and the calculation of the kinetic constants for the tar destruction. Catalysts studied include commercial Ni steam reforming catalysts and calcinated dolomites. Kinetic constants for tar destruction are calculated for several particle sizes, times- on-stream and temperatures of the catalyst and equivalence ratios in the gasifier. Such intrinsic kinetic constants allow a rigorous or scientific comparison of solids and conditions to be used in an advanced gasification process. (orig.) 4 refs.

  4. 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

  5. Residence time distribution measurements in an Advanced Pressurized Fluidized Bed Gasifier (APFBG) using radiotracer technique

    International Nuclear Information System (INIS)

    Residence time distributions (RTDs) of coal were measured at different operating conditions in a pressurized fluidized bed gasifier using radiotracer technique. Two different tracers i.e. coal labeled with gold-198 and lanthanum-140 were used as tracers. The comparison of the results obtained with the two tracers indicated that lanthanum-140 was suitable tracer for tracing coal phase in the gasifier. From the measured RTD curves, mean residence times were determined and measured data was simulated using tanks-in-series model. The simulation of data indicated that the gasifier behaved as a well-mixed reactor with minor bypassing. The results of the study were used to modify/optimize the design of the gasifier. (author)

  6. Identification of reaction zones in a commercial Sasol-Lurgi fixed bed dry bottom gasifier operating on North Dakota lignite

    Energy Technology Data Exchange (ETDEWEB)

    S.J. Mangena; J.R. Bunt; F.B. Waanders; G. Baker [Sasol Technology (Pty) Ltd., Sasolburg (South Africa)

    2011-01-15

    The objective of this study was to determine the reaction zones occurring in the Sasol-Lurgi fixed bed dry bottom (S-L FBDB) gasifier operating on North Dakota lignite. A Turn-Out sampling method and subsequent chemical analyses of the gasifier fuel bed samples was used to determine the reaction zones occurring in the commercial MK IV, S-L FBDB gasifier operating on North Dakota lignite. The reaction zones were further compared with the same reactor operating on bituminous coal. Based on the results obtained from this study it was found that about two thirds of the gasifier volume was used for drying and de-volatilising the lignite thus leaving only about a third of the reactor volume for gasification and combustion. Nonetheless, due to the high reactivity of the lignite, the char was consumed within a third of the remaining gasifier volume. Clear overlaps between the reaction zones were observed in the gasifiers thus confirming the gradual transition from one reaction zone to another as reported in literature. Due to the high moisture content in the lignite, the pyrolysis zone in the gasifiers operating on North Dakota lignite occurred lower/deeper in the gasifier fuel bed as compared to the same gasifier operating on South African bituminous coal from the Highveld coalfield. All the other reaction zones in the gasifier operating on bituminous coal were also higher in the bed compared to the lignite operation. This can therefore explain the higher gas outlet temperatures for the S-L FBDB gasifiers operating on higher rank coals when compared to the gasifiers operating on lignite. The fact that the entire reactor volume was utilized for drying, de-volatilisation, gasification and combustion with carbon conversion of {gt} 98% makes the S-L FBDB gasifier very suitable for lignite gasification. 8 refs., 8 figs., 1 tab.

  7. Comparative study of different waste biomass for energy application.

    Science.gov (United States)

    Motghare, Kalyani A; Rathod, Ajit P; Wasewar, Kailas L; Labhsetwar, Nitin K

    2016-01-01

    Biomass is available in many varieties, consisting of crops as well as its residues from agriculture, forestry, and the agro-industry. These different biomass find their way as freely available fuel in rural areas but are also responsible for air pollution. Emissions from such solid fuel combustion to indoor, regional and global air pollution largely depend on fuel types, combustion device, fuel properties, fuel moisture, amount of air supply for combustion and also on climatic conditions. In both economic and environment point of view, gasification constitutes an attractive alternative for the use of biomass as a fuel, than the combustion process. A large number of studies have been reported on a variety of biomass and agriculture residues for their possible use as renewable fuels. Considering the area specific agriculture residues and biomass availability and related transportation cost, it is important to explore various local biomass for their suitability as a fuel. Maharashtra (India) is the mainstay for the agriculture and therefore, produces a significant amount of waste biomass. The aim of the present research work is to analyze different local biomass wastes for their proximate analysis and calorific value to assess their potential as fuel. The biomass explored include cotton waste, leaf, soybean waste, wheat straw, rice straw, coconut coir, forest residues, etc. mainly due to their abundance. The calorific value and the proximate analysis of the different components of the biomass helped in assessing its potential for utilization in different industries. It is observed that ash content of these biomass species is quite low, while the volatile matter content is high as compared to Indian Coal. This may be appropriate for briquetting and thus can be used as a domestic fuel in biomass based gasifier cook stoves. Utilizing these biomass species as fuel in improved cook-stove and domestic gasifier cook-stoves would be a perspective step in the rural energy and

  8. CO-FIRING COAL: FEEDLOT AND LITTER BIOMASS FUELS

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Kalyan Annamalai; Dr. John Sweeten; Dr. Sayeed Mukhtar

    2000-10-24

    The following are proposed activities for quarter 1 (6/15/00-9/14/00): (1) Finalize the allocation of funds within TAMU to co-principal investigators and the final task lists; (2) Acquire 3 D computer code for coal combustion and modify for cofiring Coal:Feedlot biomass and Coal:Litter biomass fuels; (3) Develop a simple one dimensional model for fixed bed gasifier cofired with coal:biomass fuels; and (4) Prepare the boiler burner for reburn tests with feedlot biomass fuels. The following were achieved During Quarter 5 (6/15/00-9/14/00): (1) Funds are being allocated to co-principal investigators; task list from Prof. Mukhtar has been received (Appendix A); (2) Order has been placed to acquire Pulverized Coal gasification and Combustion 3 D (PCGC-3) computer code for coal combustion and modify for cofiring Coal: Feedlot biomass and Coal: Litter biomass fuels. Reason for selecting this code is the availability of source code for modification to include biomass fuels; (3) A simplified one-dimensional model has been developed; however convergence had not yet been achieved; and (4) The length of the boiler burner has been increased to increase the residence time. A premixed propane burner has been installed to simulate coal combustion gases. First coal, as a reburn fuel will be used to generate base line data followed by methane, feedlot and litter biomass fuels.

  9. CO-FIRING COAL: FEEDLOT AND LITTER BIOMASS FUELS

    International Nuclear Information System (INIS)

    The following are proposed activities for quarter 1 (6/15/00-9/14/00): (1) Finalize the allocation of funds within TAMU to co-principal investigators and the final task lists; (2) Acquire 3 D computer code for coal combustion and modify for cofiring Coal:Feedlot biomass and Coal:Litter biomass fuels; (3) Develop a simple one dimensional model for fixed bed gasifier cofired with coal:biomass fuels; and (4) Prepare the boiler burner for reburn tests with feedlot biomass fuels. The following were achieved During Quarter 5 (6/15/00-9/14/00): (1) Funds are being allocated to co-principal investigators; task list from Prof. Mukhtar has been received (Appendix A); (2) Order has been placed to acquire Pulverized Coal gasification and Combustion 3 D (PCGC-3) computer code for coal combustion and modify for cofiring Coal: Feedlot biomass and Coal: Litter biomass fuels. Reason for selecting this code is the availability of source code for modification to include biomass fuels; (3) A simplified one-dimensional model has been developed; however convergence had not yet been achieved; and (4) The length of the boiler burner has been increased to increase the residence time. A premixed propane burner has been installed to simulate coal combustion gases. First coal, as a reburn fuel will be used to generate base line data followed by methane, feedlot and litter biomass fuels

  10. 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

  11. Biomass Thermochemical Conversion Program. 1983 Annual report

    Energy Technology Data Exchange (ETDEWEB)

    Schiefelbein, G.F.; Stevens, D.J.; Gerber, M.A.

    1984-08-01

    Highlights of progress achieved in the program of thermochemical conversion of biomass into clean fuels during 1983 are summarized. Gasification research projects include: production of a medium-Btu gas without using purified oxygen at Battelle-Columbus Laboratories; high pressure (up to 500 psia) steam-oxygen gasification of biomass in a fluidized bed reactor at IGT; producing synthesis gas via catalytic gasification at PNL; indirect reactor heating methods at the Univ. of Missouri-Rolla and Texas Tech Univ.; improving the reliability, performance, and acceptability of small air-blown gasifiers at Univ. of Florida-Gainesville, Rocky Creek Farm Gasogens, and Cal Recovery Systems. Liquefaction projects include: determination of individual sequential pyrolysis mechanisms at SERI; research at SERI on a unique entrained, ablative fast pyrolysis reactor for supplying the heat fluxes required for fast pyrolysis; work at BNL on rapid pyrolysis of biomass in an atmosphere of methane to increase the yields of olefin and BTX products; research at the Georgia Inst. of Tech. on an entrained rapid pyrolysis reactor to produce higher yields of pyrolysis oil; research on an advanced concept to liquefy very concentrated biomass slurries in an integrated extruder/static mixer reactor at the Univ. of Arizona; and research at PNL on the characterization and upgrading of direct liquefaction oils including research to lower oxygen content and viscosity of the product. Combustion projects include: research on a directly fired wood combustor/gas turbine system at Aerospace Research Corp.; adaptation of Stirling engine external combustion systems to biomass fuels at United Stirling, Inc.; and theoretical modeling and experimental verification of biomass combustion behavior at JPL to increase biomass combustion efficiency and examine the effects of additives on combustion rates. 26 figures, 1 table.

  12. Plasma gasification of refuse derived fuel in a single-stage system using different gasifying agents.

    Science.gov (United States)

    Agon, N; Hrabovský, M; Chumak, O; Hlína, M; Kopecký, V; Masláni, A; Bosmans, A; Helsen, L; Skoblja, S; Van Oost, G; Vierendeels, J

    2016-01-01

    The renewable evolution in the energy industry and the depletion of natural resources are putting pressure on the waste industry to shift towards flexible treatment technologies with efficient materials and/or energy recovery. In this context, a thermochemical conversion method of recent interest is plasma gasification, which is capable of producing syngas from a wide variety of waste streams. The produced syngas can be valorized for both energetic (heat and/or electricity) and chemical (ammonia, hydrogen or liquid hydrocarbons) end-purposes. This paper evaluates the performance of experiments on a single-stage plasma gasification system for the treatment of refuse-derived fuel (RDF) from excavated waste. A comparative analysis of the syngas characteristics and process yields was done for seven cases with different types of gasifying agents (CO2+O2, H2O, CO2+H2O and O2+H2O). The syngas compositions were compared to the thermodynamic equilibrium compositions and the performance of the single-stage plasma gasification of RDF was compared to that of similar experiments with biomass and to the performance of a two-stage plasma gasification process with RDF. The temperature range of the experiment was from 1400 to 1600 K and for all cases, a medium calorific value syngas was produced with lower heating values up to 10.9 MJ/Nm(3), low levels of tar, high levels of CO and H2 and which composition was in good agreement to the equilibrium composition. The carbon conversion efficiency ranged from 80% to 100% and maximum cold gas efficiency and mechanical gasification efficiency of respectively 56% and 95%, were registered. Overall, the treatment of RDF proved to be less performant than that of biomass in the same system. Compared to a two-stage plasma gasification system, the produced syngas from the single-stage reactor showed more favourable characteristics, while the recovery of the solid residue as a vitrified slag is an advantage of the two-stage set-up. PMID:26210232

  13. Automotive fuels from biomass via gasification

    International Nuclear Information System (INIS)

    There exists already a market of bio-automotive fuels i.e. bioethanol and biodiesel produced from food crops in many countries. From the viewpoint of economics, environment, land use, water use and chemical fertilizer use, however, there is a strong preference for the use of woody biomass and various forest/agricultural residues as the feedstock. Thus, the production of 2nd generation of bio-automotive fuels i.e. synthetic fuels such as methanol, ethanol, DME, FT-diesel, SNG and hydrogen through biomass gasification seems promising. The technology of producing synthetic fuels is well established based on fossil fuels. For biomass, however, it is fairly new and the technology is under development. Starting from the present market of the 1st generation bio-automotive fuels, this paper is trying to review the technology development of the 2nd generation bio-automotive fuels from syngas platform. The production of syngas is emphasized which suggests appropriate gasifier design for a high quality syngas production. A number of bio-automotive fuel demonstration plant will be presented, which gives the state of the art in the development of BTS (biomass to synthetic fuels) technologies. It can be concluded that the 2nd generation bio-automotive fuels are on the way to a breakthrough in the transport markets of industrial countries especially for those countries with a strong forest industry. (author)

  14. Biomass power; Biomasse-Energie

    Energy Technology Data Exchange (ETDEWEB)

    Woergetter, M.

    2003-07-01

    The author reports about use of biomass in Austria and Bavaria: power generation, production of biodiesel, bioethanol, energy efficiency of small biomass furnaces. (uke) [German] Bioenergie wird von breiten Kreisen als wichtiger Ansatz in Richtung einer nachhaltigen Entwicklung in Europa gesehen. Die Herausforderung liegt dabei im neuen Herangehen an Entscheidungen; Dimensionen der Wirtschaft, der Umwelt und der Gesellschaft sind dabei zu beruecksichtigen. Bioenergie ist somit keine reine Frage der Umwelt, sondern zielt auf den Umbau unseres Systems in Richtung Nachhaltigkeit. (orig.)

  15. 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.

  16. Electric energy generation using biomass gasification; Generacion de energia electrica a partir de la gasificacion de biomassa

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz, J.; Arauzo, J.; Gonzalo, Alberto; Sanchez, Jose Luis [Universidad de Zaragoza, Aragon (Spain). Inst. de Investigacion. 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. [Bioware Tecnologia, Campinas, SP (Brazil)

    2004-07-01

    Gasification experiments have been carried out with a atmospheric pressure down draft gasifier of a capacity of 250 kg/h of biomass. Biomass used have been almond shells and olive cut. Results obtained show a similar behaviour in gas composition with two biomass. A small fraction of the generated gas from the gasifier has been fed to a small generator of 4 kV A. The gas has been previously cleaned and dried by means of a scrubber and a condenser, to remove tar products. The generator has been operated with a great stability without any modification, and energy generated with gas from gasification are relatively close to the values obtained with conventional fuels such as gasoline or commercial butane. (author)

  17. York County Energy Partners CFB Cogeneration Project. Annual report, [September 30, 1992--September 30, 1993

    Energy Technology Data Exchange (ETDEWEB)

    1994-03-01

    The Department of Energy, under the Clean Coal Technology program, proposes to provide cost-shared financial assistance for the construction of a utility-scale circulating fluidized bed technology cogeneration facility by York County Energy Partners, L.P (YCEP). YCEP, a project company of ir Products and Chemicals, Inc., would design, construct and operate a 250 megawatt (gross) coal-fired cogeneration facility on a 38-acre parcel in North Codorus Township, York County, Pennsylvania. The facility would be located adjacent to the P. H. Glatfelter Company paper mill, the proposed steam host. Electricity would be delivered to Metropolitan Edison Company. The facility would demonstrate new technology designed to greatly increase energy efficiency and reduce air pollutant emissions over current generally available commercial technology which utilizes coal fuel. The facility would include a single train circulating fluidized bed boiler, a pollution control train consisting of limestone injection for reducing emissions of sulfur dioxide by greater than 92 percent, selective non-catalytic reduction for reducing emissions of nitrogen oxides, and a fabric filter (baghouse) for reducing emissions of particulates. Section II of this report provides a general description of the facility. Section III describes the site specifics associated with the facility when it was proposed to be located in West Manchester Township. After the Cooperative Agreement was signed, YCEP decided to move the proposed site to North Codorus Township. The reasons for the move and the site specifics of that site are detailed in Section IV. This section of the report also provides detailed descriptions of several key pieces of equipment. The circulating fluidized bed boiler (CFB), its design scale-up and testing is given particular emphasis.

  18. Emission of hydrocarbons and NOx at low levels of excess air in CFB

    International Nuclear Information System (INIS)

    Low NOx operation at low excess air levels heighten the risk of increasing the level of hazardous and polluting emissions from the boiler. These emissions are mainly of two types, greenhouse gases and the mutageneous compounds. The aim of this project has been to show which types of emissions and their correlation you can expect when firing a CFB at low excess air levels. Results: The NOx emission decreases asymptotically with increased CO-level. High load gives higher NOx -emissions. There is no significant difference in average NOx value between wood fuel and RDF-mix. The total hydrocarbon (THC) emission level increases exponentially with increased COlevel. There was no significant difference between wood and RDF-mix. Measurements of NOx, O2, CO (dry gas) and THC were made each second. The measurements of light hydrocarbons (VOC) showed only methane and ethene, both with a good correlation to CO. Below 1000 ppm of CO there is practically no ethene. Above 1000-2000 ppm of CO there is a rapidly increasing emission of ethene. The emission levels at given CO-level are influenced by the furnace temperature. The POM, PNA and Ames test analysis showed good correlation with CO and THC. The results indicate an emission increase at about 200-500 ppm of CO and 10-20 ppm of THC. Dioxin was measured on three occasions with RDF-mix as fuel. The measurements showed an increase of dioxin emission at increased THC-emission. The supply of ammonia, into the flue gas before the cyclones, gave no significant change in hydrocarbon or CO-emission levels. CO, THC and Ames Test are probably good indicators of environmental hazardous compounds. The amount of mutageneous compounds are in general only increased when a certain level of CO is reached. 6 refs, 45 figs, 5 tabs, 7 appendices

  19. Investigation on syngas production via biomass conversion through the integration of pyrolysis and air–steam gasification processes

    International Nuclear Information System (INIS)

    Highlights: • Innovation in gasifier design. • Integration of pyrolysis and steam gasification processes. • Energy saving, improvement of gasifier efficiency, syngas and hydrogen yield. • Overall investigation on gasification parameters. • Optimization conditions of integration of pyrolysis and gasification process. - Abstract: Fuel production from agro-waste has become an interesting alternative for energy generation due to energy policies and greater understanding of the importance of green energy. This research was carried out in a lab-scale gasifier and coconut shell was used as feedstock in the integrated process. In order to acquire the optimum condition of syngas production, the effect of the reaction temperature, equivalence ratio (ER) and steam/biomass (S/B) ratio was investigated. Under the optimized condition, H2 and syngas yield achieved to 83.3 g/kg feedstock and 485.9 g/kg feedstock respectively, while LHV of produced gases achieved to 12.54 MJ/N m3

  20. 循环流化床锅炉破碎设备的布置及选型%Arrangement and Type Selection of Crushing Equipment in CFB

    Institute of Scientific and Technical Information of China (English)

    刘国瑞

    2015-01-01

    This paper analyze the selection of fuel crusher for CFB in detail, according to the characteristic of the high requirement of the granularity of coal-fired of CFB. The selection of fuel crusher for CFB can get some reference by this paper.%针对循环流化床锅炉对人炉煤粒度要求较高的特点,对循环流化床锅炉破碎设备的选型进行了详细分析.希望本文能对其他循环流化床锅炉原煤破碎设备的选型提供一定的借鉴.

  1. 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

  2. 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

  3. Detailed model for practical pulverized coal furnaces and gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Smith, P.J.; Smoot, L.D.

    1989-08-01

    This study has been supported by a consortium of nine industrial and governmental sponsors. Work was initiated on May 1, 1985 and completed August 31, 1989. The central objective of this work was to develop, evaluate and apply a practical combustion model for utility boilers, industrial furnaces and gasifiers. Key accomplishments have included: Development of an advanced first-generation, computer model for combustion in three dimensional furnaces; development of a new first generation fouling and slagging submodel; detailed evaluation of an existing NO{sub x} submodel; development and evaluation of an improved radiation submodel; preparation and distribution of a three-volume final report: (a) Volume 1: General Technical Report; (b) Volume 2: PCGC-3 User's Manual; (c) Volume 3: Data Book for Evaluation of Three-Dimensional Combustion Models; and organization of a user's workshop on the three-dimensional code. The furnace computer model developed under this study requires further development before it can be applied generally to all applications; however, it can be used now by specialists for many specific applications, including non-combusting systems and combusting geseous systems. A new combustion center was organized and work was initiated to continue the important research effort initiated by this study. 212 refs., 72 figs., 38 tabs.

  4. 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

  5. Efficiency tests on the pyrolysis gasifier stove Peko Pe

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, P.S.

    1996-10-01

    This paper presents results from water boiling tests on the pyrolysis gasifier stove Peko Pe, which has been developed by the Norwegian Paal Wendelbo. The stove efficiency determined vary between 21 and 29% when burning dry Danish woodchip (10% moisture) with an estimated caloric value of 16 MJ/kg. CO-emissions have been determined with varying distance between the stove and the pot to estimate the combustion efficiency. Efficiency tests performed in Adjumani refugee camp with grass as fuel show a stove efficiency of 25-29% with a caloric value of 14 MJ/kg. It has not been possible to determine the water content in the grass. In Adjumani refugee camp it was furthermore found that the stove was able to provide sufficient energy from solid combustion, after the pyrolysis was stopped, to boil water for additional 25-30 minutes with lid. This effect was not seen in the tests on woodchips in Denmark. Advantages and disadvanges of the stove compared to three-stone stoves are discussed and perspectives are outlined for further improvements of the stove. (au)

  6. The moisture effect on wood combustion in an Updraft Gasifier

    International Nuclear Information System (INIS)

    Full text: This paper studies the fuel moisture content effect on the wood combustion behavior in the gasifier. The combustion process is evaluated with the variation of fuels moisture content, i.e. set at 17 %, 31 %, and 40 % respectively. The ignition front rate decreased with increasing fuel moisture content which resulted in slower gasification process in the chamber. The temperature and oxide of nitrogen (NO) concentration are decreased with the increase of the moisture in the fuel. Furthermore, the concentration of carbon monoxide (CO) increases while the change for carbon dioxide (CO2) and oxygen (O2) concentrations are only around 1% with the variation of this operating parameter. At highest gasification efficiency of 92.7 %, the moisture content of the fuel is best set at 16.1-17 % giving outlet operating temperature of 500 degree Celsius and exhaust gas concentrations with 1500 ppm of CO, 2.8 % of CO2, 30 ppm of NO and 17.6 % of O2 respectively. (author)

  7. Biomass potential

    Energy Technology Data Exchange (ETDEWEB)

    Asplund, D. [VTT Energy, Espoo (Finland)

    1996-12-31

    Biomass resources of the industrialised countries are enormous, if only a small fraction of set-aside fields were used for energy crops. Forest resources could also be utilised more efficiently than at present for large-scale energy production. The energy content of the annual net growth of the total wood biomass is estimated to be 180 million toe in Europe without the former USSR, and about 50 million toe of that in the EC area, in 1990. Presently, the harvesting methods of forest biomass for energy production are not yet generally competitive. Among the most promising methods are integrated harvesting methods, which supply both raw material to the industry and wood fuel for energy production. Several new methods for separate harvesting of energy wood are being developed in many countries. (orig.)

  8. Criteria for selection of dolomites and catalysts for tar elimination from biomass gasification gas. Kinetic constants

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-12-31

    Calcined dolomites and commercial steam reforming catalysts are used downstream biomass gasifiers for hot catalytic raw gas cleaning. To further compare these solids under a rigorous basis, a reaction network and a kinetic model are presented. The apparent kinetic constant for the tar reduction is here proposed as a basis of comparison. Tar sampling and analysis, and the units used for the space-time in the catalytic reactor affect the kinetic constants observed. (author) (2 refs.)

  9. Integrated gasification combined cycle and steam injection gas turbine powered by biomass joint-venture evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Sterzinger, G J [Economics, Environment and Regulation, Washington, DC (United States)

    1994-05-01

    This report analyzes the economic and environmental potential of biomass integrated gasifier/gas turbine technology including its market applications. The mature technology promises to produce electricity at $55--60/MWh and to be competitive for market applications conservatively estimated at 2000 MW. The report reviews the competitiveness of the technology of a stand-alone, mature basis and finds it to be substantial and recognized by DOE, EPRI, and the World Bank Global Environmental Facility.

  10. Integrated gasification combined cycle and steam injection gas turbine powered by biomass joint-venture evaluation

    International Nuclear Information System (INIS)

    This report analyzes the economic and environmental potential of biomass integrated gasifier/gas turbine technology including its market applications. The mature technology promises to produce electricity at $55--60/MWh and to be competitive for market applications conservatively estimated at 2000 MW. The report reviews the competitiveness of the technology of a stand-alone, mature basis and finds it to be substantial and recognized by DOE, EPRI, and the World Bank Global Environmental Facility

  11. Catalytic destruction of tar in biomass derived producer gas

    International Nuclear Information System (INIS)

    The purpose of this study is to investigate catalytic destruction of tar formed during gasification of biomass, with the goal of improving the quality of the producer gas. This work focuses on nickel based catalysts treated with alkali in an effort to promote steam gasification of the coke that deposits on catalyst surfaces. A tar conversion system consisting of a guard bed and catalytic reactor was designed to treat the producer gas from an air blown, fluidized bed biomass gasifier. The guard bed used dolomite to crack the heavy tars. The catalytic reactor was used to evaluate three commercial steam reforming catalysts. These were the ICI46-1 catalyst from Imperial Chemical Industry and Z409 and RZ409 catalysts from Qilu Petrochemical Corp. in China. A 0.5-3 l/min slipstream from a 5 tpd biomass gasifier was used to test the tar conversion system. Gas and tar were sampled before and after the tar conversion system to evaluate the effectiveness of the system. Changes in gas composition as functions of catalytic bed temperature, space velocity and steam/TOC (total organic carbon) ratio are presented. Structural changes in the catalysts during the tests are also described

  12. Biomass IGCC

    Energy Technology Data Exchange (ETDEWEB)

    Salo, K.; Keraenen, H. [Enviropower Inc., Espoo (Finland)

    1996-12-31

    Enviropower Inc. is developing a modern power plant concept based on pressurised fluidized-bed gasification and gas turbine combined cycle (IGCC). The process is capable of maximising the electricity production with a variety of solid fuels - different biomass and coal types - mixed or separately. The development work is conducted on many levels. These and demonstration efforts are highlighted in this article. The feasibility of a pressurised gasification based processes compared to competing technologies in different applications is discussed. The potential of power production from biomass is also reviewed. (orig.) 4 refs.

  13. Economic evaluation of externally fired gas turbine cycles for small-scale biomass cogeneration

    Energy Technology Data Exchange (ETDEWEB)

    Anheden, Marie [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Chemical Engineering and Technology

    2001-01-01

    In this conceptual study, externally fired gas turbine (EFGT) cycles in combination with a biomass-fueled, atmospheric circulating fluidized bed (CFB) furnace are investigated for small scale heat and power production ({approx} 8 MW fuel input). Three cycle configurations are considered: closed cycle, with nitrogen, helium, and a helium/carbon dioxide mixture as working fluids; open cycle operating in parallel to the CFB system; and open cycle with a series connection to the CFB system. Intercooling, postcooling, and recuperation are employed with the goal of maximizing efficiency. Aside from a thermodynamic performance analysis, the study includes an economic analysis of both the closed and open externally fired gas turbine configurations, and comparisons are made with existing and emerging alternatives for small-scale biomass cogeneration. Simulation results show that thermodynamic performance varies slightly between the different configurations and working fluids, with electrical efficiencies of 31-38% (LHV) and total efficiency of 85-106% (LHV). The economic evaluation shows that the turbomachinery and the CFB furnace dominate the total plant cost, with each contributing about 1/3 of the total installed equipment cost. The specific capital cost for installation in Sweden in 1998 currency is calculated as 26-31 kSEK/kW{sub e} which is equivalent to 3 200-3 900 USD/kW{sub e} or 2 700-3 300 EUR/kW{sub e} .The cost of electricity, COE, is estimated to 590-670 SEK/MWh{sub e} (equivalent to 73-84 USD/MWh{sub e} or 62-71 EUR/MWh{sub e}) for 4 000 full load hours per year in a cogeneration application. Comparing the economic results for the externally fired gas turbine cycles in a slightly larger scale (40-50 MW{sub f}) to the economics of conventional biomass fired steam turbine cycles shows that the cost of electricity for the two plant configurations are roughly the same with a COE of 300-350 SEK/MWh{sub e}. It is believed that the economic performance of the EFGT

  14. Electricity cogeneration evaluation from cane bagasse in gasifier systems/gas turbine; Avaliacao da cogeracao de eletricidade a partir de bagaco de cana em sistemas de gaseificador/turbina a gas

    Energy Technology Data Exchange (ETDEWEB)

    Coelho, Suani Teixeira

    1992-07-01

    Before the beginning of PROALCOOL in 1975, the first effective program in the world using biomass in large scale as an automotive fuel, sugar/alcohol industries already used sugar cane bagasse - a by-product of sugar/alcohol production - to generate energy for sugar production. Currently, besides the fact that they are self-sufficient in thermal/electrical energy, sugar/alcohol industries produce small electricity excess which is exported to local utilities. Gasifier/gas turbine systems are more advanced technologies which are being developed and shall be commercialized in eight to ten years approximately, presenting much higher efficiency, at low cost and inducing more exportable electricity. In this study, possibilities of gasifier/gas turbine systems are evaluated and projections of bagasse based electricity production are presented, until year 2010, for Sao Paulo state and Brazil. Generation costs of gasified bagasse based electricity are calculated: they shall be lower than electricity cost from fossil origin. Influence of electricity sale on the reduction of alcohol production cost are also evaluated for several opportunity costs of bagasse. Environmental and social impacts are analyzed, including evaluation of the cost of avoided carbon, related to the substitution of fossil fuel by sugar cane bagasse in thermoelectric power plants. (author)

  15. Method and apparatus for automated, modular, biomass power generation

    Science.gov (United States)

    Diebold, James P.; Lilley, Arthur; Browne, Kingsbury III; Walt, Robb Ray; Duncan, Dustin; Walker, Michael; Steele, John; Fields, Michael; Smith, Trevor

    2011-03-22

    Method and apparatus for generating a low tar, renewable fuel gas from biomass and using it in other energy conversion devices, many of which were designed for use with gaseous and liquid fossil fuels. An automated, downdraft gasifier incorporates extensive air injection into the char bed to maintain the conditions that promote the destruction of residual tars. The resulting fuel gas and entrained char and ash are cooled in a special heat exchanger, and then continuously cleaned in a filter prior to usage in standalone as well as networked power systems.

  16. 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.

  17. 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

  18. Biomass Steam Gasification with In-Situ CO2 Capture for Enriched Hydrogen Gas Production: A Reaction Kinetics Modelling Approach

    Directory of Open Access Journals (Sweden)

    Mohamed Ibrahim Abdul Mutalib

    2010-08-01

    Full Text Available Due to energy and environmental issues, hydrogen has become a more attractive clean fuel. Furthermore, there is high interest in producing hydrogen from biomass with a view to sustainability. The thermochemical process for hydrogen production, i.e. gasification, is the focus of this work. This paper discusses the mathematical modeling of hydrogen production process via biomass steam gasification with calcium oxide as sorbent in a gasifier. A modelling framework consisting of kinetics models for char gasification, methanation, Boudouard, methane reforming, water gas shift and carbonation reactions to represent the gasification and CO2 adsorption in the gasifier, is developed and implemented in MATLAB. The scope of the work includes an investigation of the influence of the temperature, steam/biomass ratio and sorbent/biomass ratio on the amount of hydrogen produced, product gas compositions and carbon conversion. The importance of different reactions involved in the process is also discussed. It is observed that hydrogen production and carbon conversion increase with increasing temperature and steam/biomass ratio. The model predicts a maximum hydrogen mole fraction in the product gas of 0.81 occurring at 950 K, steam/biomass ratio of 3.0 and sorbent/biomass ratio of 1.0. In addition, at sorbent/biomass ratio of 1.52, purity of H2 can be increased to 0.98 mole fraction with all CO2 present in the system adsorbed.

  19. Influence of Coal nature and Structure on Ash Size Formation Characteristic and Related pollutant Emissions During CFB Combustion

    Institute of Scientific and Technical Information of China (English)

    MinQIAN; YongjieNA; 等

    2000-01-01

    The size distribution of coal particles in a Circulating Fluidized Bed(CFB) boiler plays a crucial role in the complicated combustion,heat exchange and pollutant emissions in such a plant.Therefore,it is fundamental to study the different factors having influence on the size distribution of coal particles.Above all,the coal itself and in particular,the coal comminution phenomenon is a very influent factor.In the frame of this work,the coal nature (eleentary compostion) and coal internal structure (mineral componeents) are studied in detail.At this intermediary stage,experients on three typical Chinese coals on a 1.5 MWt CFBC pilot plant have been made.Some primary fragmentation test hae also been made in a small lab scale fluidized bed reactor.The resutls from the hot pilot test show i)the variation of coal ash distributions and other CFB performance data due to the cyclone and the coal characteristics and ii) the variation of desulfurization efficiency with limestone.Whereas the bench scale primary fragmentation test,likely linked to the caking propriety of a coal,does not seem to change considerable the char size distribution.

  20. 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)

  1. 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)

  2. 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.

  3. Mineralogy and leachability of gasified sewage sludge solid residues

    International Nuclear Information System (INIS)

    Highlights: → Study of the solid residue's characterization, solids resulting from sewage sludge gasification. → Multi-technique approach is used to study the evolution of the mineralogy including innovative methods. → Sewage sludge mineralogy undergoes significant transformations during thermal treatment, influenced mainly by temperature and heating atmosphere. → Heavy metals are differently stabilized and located. → Steam gasification is an attractive route for sewage sludge disposal in view of the mobility of heavy metals retained in the residues. - Abstract: Gasification of sewage sludge produces combustible gases as well as tar and a solid residue as by-products. This must be taken into account when determining the optimal thermal conditions for the gasification process. In this study, the influence of temperature, heating atmosphere and residence time on the characteristics of the gasified sewage sludge residues is investigated. ICP-AES analyses reveal that the major chemical elements in the char residues are phosphorus, calcium, iron and silicon. Heavy metals such as copper, zinc, chromium, nickel and lead are also present at relatively high levels - from 50 to more than 1000 mg/kg of dry matter. The major mineral phases' identification - before and after heating - as well as their morphology and approximate chemistry (XRD and SEM-EDX) demonstrate that a number of transformations take place during gasification. These are influenced by the reactor's temperature and the oxidative degree of its internal atmosphere. The copper-, zinc- and chromium-bearing phases are studied using chemometric tools, showing that the distribution of those metals among the mineral phases is considerably different. Finally, batch-leaching tests reveal that metals retained in the residue are significantly stabilized after thermal treatment to a higher or lower extent, depending on the thermal conditions applied.

  4. Biotechnology of biomass conversion

    International Nuclear Information System (INIS)

    This book covers: An introduction to biomass crops; The microbiology of fermentation processes; The production of ethanol from biomass crops, such as sugar cane and rubbers; The energy of biomass conversion; and The economics of biomass conversion

  5. Biomass shock pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Holtzapple, Mark T.; Madison, Maxine Jones; Ramirez, Rocio Sierra; Deimund, Mark A.; Falls, Matthew; Dunkelman, John J.

    2014-07-01

    Methods and apparatus for treating biomass that may include introducing a biomass to a chamber; exposing the biomass in the chamber to a shock event to produce a shocked biomass; and transferring the shocked biomass from the chamber. In some aspects, the method may include pretreating the biomass with a chemical before introducing the biomass to the chamber and/or after transferring shocked biomass from the chamber.

  6. Comparison between externally fired gas turbine and gasifier-gas turbine system for the olive oil industry

    International Nuclear Information System (INIS)

    The olive oil industry generates during the extraction process several solid wastes as olive tree leaves and prunings, exhausted pomace and olive pits. These renewable wastes could be used for power and heat applications. The aim of this paper is to compare the performance of two small-scale CHP systems: a gasification- gas turbine system and an EFGT (externally fired gas turbine system). For this reason, several parameters have been calculated: generated heat and power, electric and overall efficiencies, biomass consumption, exergy efficiency, optimum pressure ratio, etc. These systems provide 30 kWe and about 60kWth. Simulation results show that the electrical and overall efficiencies achieved in EFGT system (19.1% and 59.3%, respectively) are significantly higher than those obtained in the gasification plant (12.3% and 45.4%). The proposed CHP systems have been modeled using Cycle-Tempo® software. -- Highlights: ► Comparison between externally fired gas turbine and gasifier-gas turbine system. ► Olive oil industry generates several solid wastes as olive tree leaves and prunings. ► Thermodynamic parameters have been calculated. ► Systems have been modeled using Cycle-Tempo® software. ► Simulation results show electrical and overall efficiencies achieved in the systems.

  7. 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

  8. Opportunities for small scale biomass-electricity systems in Kenya

    Energy Technology Data Exchange (ETDEWEB)

    Senelwa, K.; Sims, R.E.H. [Massey University, Palmerston North (New Zealand). Institute of Technology and Engineering

    1999-09-01

    Surveys of rural household energy use activities incorporating the production and utilisation of woody biomass, and of the forest products industries incorporating forest harvesting, wood processing and residues generation, were undertaken to assess the availability of wood biomass that could be utilised in biomass-electricity systems in Kenya. Government forests could not be relied upon to supply fuelwood to decentralised village gasifier installations as they were far from main village clusters, and were mostly protected against subsistence harvesting. Although farm forestry on farms in rural areas was assessed to be well established, the standing stock of woody biomass of 0.7-4.6 m{sup 3} per farm was considered inadequate for continuous operation of a downdraft gasifier. The greatest potential was at sawmills processing more than 720 tonnes of logs per year and generating more than 390 tonnes of solid residues per year. Each of the 73 mills in this category (medium-large scale) had an annual potential to generate more than 0.85 x 10{sup 6} m{sup 3} of low heating value gas (4.6 MJ/m{sup 3}). The total annual gas potential from the 73 mills was 221 million cubic metres (Mm{sup 3}), equivalent to 24,000 tonnes of oil. The gas could generate up to 76 GWh (electric), and if part of a co-generation system, an additional 141.4 GWh of heat could be harnessed and used in timber drying kilns. Factors that determine the viability of biomass-electricity systems are discussed. The need for a demonstration unit installation at one of the sawmills is emphasised.

  9. Comparison of Refractory Performance in Black Liquor Gasifiers and a Smelt Test System

    International Nuclear Information System (INIS)

    Prior laboratory corrosion studies along with experience at the black liquor gasifier in New Bern, North Carolina, clearly demonstrate that serious material problems exist with the gasifier's refractory lining. Mullite-based and alumina-based refractories used at the New Bern facility suffered significant degradation even though they reportedly performed adequately in smaller scale systems. Oak Ridge National Laboratory's involvement in the failure analysis, and the initial exploration of suitable replacement materials, led to the realization that a simple and reliable, complementary method for refractory screening was needed. The development of a laboratory test system and its suitability for simulating the environment of black liquor gasifiers was undertaken. Identification and characterization of corrosion products were used to evaluate the test system as a rapid screening tool for refractory performance and as a predictor of refractory lifetime. Results from the test systems and pl ants were qualitatively similar

  10. 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...

  11. Electrifying biomass

    International Nuclear Information System (INIS)

    British Columbia's (BC) energy plan was outlined in this PowerPoint presentation. BC Hydro is the third largest electric utility in Canada with a generating capacity of 11,000 MW, 90 per cent of which is hydro generation. Various independent power project (IPP) biomass technologies were outlined, including details of biogas, wood residue and municipal solid waste facilities. An outline of BC Hydro's overall supply mix was presented, along with details of the IPP supply mix. It was suggested that the cancellation of the Duke Point power project has driven growth in the renewable energy sector. A chart of potential energy contribution by resource type was presented, as well as unit energy cost ranges. Resources included small and large hydro; demand side management; resource smart natural gas; natural gas; coal; wind; geothermal; biomass; wave; and tidal. The acquisition process was reviewed. Details of calls for tenders were presented, and issues concerning bidder responsibility and self-selection were examined. It was observed that wood residue presents a firm source of electricity that is generally local, and has support from the public. In addition, permits for wood residue energy conversion are readily available. However, size limitations, fuel risks, and issues concerning site control may prove to be significant challenges. It was concluded that the success of biomass energy development will depend on adequate access and competitive pricing. tabs., figs

  12. Analysis of the fly ash from the processing of wood chips in a pilot-scale downdraft gasifier: Comparison of inorganic constituents determined by PIXE and ICP-AES

    International Nuclear Information System (INIS)

    Gasification of biomass ultimately generates at least one solid byproduct in which the inorganic constituents of the biomass are concentrated. Given the potential for utilization, or issues with disposal, facile methods are needed for determining the compositions of the fly ashes from recently-available gasifier-based bioenergy systems. Proton induced x-ray emission spectroscopy (PIXE) and inductively coupled plasma atomic emission spectroscopy (ICP-AES) were used to characterize the fly ash recovered from a pilot-scale (25 kW) modular bioenergy system operated with wood chips as the feedstock. The composition of the fly ash from the downdraft gasifier showed some similarities to compositions reported for boiler wood ashes, apart from one half of the material being unburned carbon. Although ICP-AES showed greater sensitivity for the analysis of the fly ash, especially for small amounts of heavy metal contaminants, PIXE proved to be a powerful analytical tool for screening of elements from sodium to uranium. Such broad spectrum screenings could prevent the inadvertent land application of unsuspected pollutant elements. Fly ashes from biomass gasification appear to be suitable for use as ash-based fertilizers for forest lands; however, combustion to remove unburned carbon may be advisable. -- Highlights: ► Fly ash composition data for commercial modular bioenergy systems are now reported. ► PIXE analysis better suited for analysis of fly ashes rich in silicates. Fly ashes generated by biomass gasification may be suitable for land application. ► Combustion of biomass-derived fly ashes is recommended before use as soil amendments

  13. Development of Methane and Nitrous Oxide Emission Factors for the Biomass Fired Circulating Fluidized Bed Combustion Power Plant

    OpenAIRE

    Chang-Sang Cho; Jae-Hwan Sa; Ki-Kyo Lim; Tae-Mi Youk; Seung-Jin Kim; Seul-Ki Lee; Eui-Chan Jeon

    2012-01-01

    This study makes use of this distinction to analyze the exhaust gas concentration and fuel of the circulating fluidized bed (CFB) boiler that mainly uses wood biomass, and to develop the emission factors of Methane (CH4), Nitrous oxide (N2O). The fuels used as energy sources in the subject working sites are Wood Chip Fuel (WCF), RDF and Refused Plastic Fuel (RPF) of which heating values are 11.9 TJ/Gg, 17.1 TJ/Gg, and 31.2 TJ/Gg, respectively. The average concentrations of CH4 and N2O were me...

  14. Slag properties of blending coal in an industrial OMB coal water slurry entrained-flow gasifier

    International Nuclear Information System (INIS)

    Highlights: • Slag properties of blending coal from an industrial gasifier are investigated. • Transformation behaviors of mineral matters are calculated by thermodynamic model. • The optimized blending ratio of given coals is in the range of 0.3–0.5. - Abstract: Blending coal as feedstock is a potential cost-effective way to reduce the gasifier operation cost. Slag properties of blending coal from an industrial Opposed Multi-Burner (OMB) coal water slurry entrained-flow gasifier was investigated in this paper. Experimental data from an OMB entrained-flow gasifier using a blend of high quality coal with a relatively high ash content coal as feedstock were analyzed. The transformation behaviors of the slag from an industrial gasifier were investigated by viscosity analysis and thermodynamic calculation with assistance of FactSage software and validated by the industrial data. The results show that the slag properties were diversified and differ based on the coal blending ratios. It was discovered that the optimized blending ratio (high quality coal/high ash content coal) was in the range of 0.3–0.5. Most of the mineral matter was transformed into Ca aluminosilicates with relatively high liquidus temperatures around 1500 °C. As the proportion of coal with higher ash and SiO2 content increases, the slag shows a trend of transformation to mullite. The liquidus temperature decreased at first and then increased gradually as the ratio was increased, which provided a minimum blending ratio of ∼0.3, consequently with about 8% reduction of feeding cost. Meanwhile, the viscosity of the slag also increased as the blending ratio of higher ash and SiO2 content coal increased. At this point it should be noted that the loading and operating temperature of the gasifier had to be adjusted as the blending ratio fluctuated in order to maintain proper operation

  15. 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

  16. Pressure-drop predictions in a fixed-bed coal gasifier

    OpenAIRE

    Bunt, John Reginald; Luckos, Adam

    2011-01-01

    In the Sasol Synfuels plant in Secunda, Sasol-Lurgi fixed-bed dry-bottom gasifiers are used for the conversion of low-grade bituminous coals to synthesis gas (syngas). The gasifiers are fed with lump coal having a particle size in the range from 5 to 100 mm. Operating experience shows that the average particle size and particle-size distribution (PSD) of feed coal, char and ash influence the pressure drop across the bed and the gas-flow distribution within the bed. These hydrodynamic phenomen...

  17. The Design, Construction and Operation of a 75 kW Two-Stage Gasifier

    DEFF Research Database (Denmark)

    Henriksen, Ulrik Birk; Ahrenfeldt, Jesper; Jensen, Torben Kvist;

    2003-01-01

    The Two-Stage Gasifier was operated for several weeks (465 hours) and of these 190 hours continuously. The gasifier is operated automatically unattended day and night, and only small adjustments of the feeding rate were necessary once or twice a day. The operation was successful, and the output as...... expected. The engine operated well on the produced gas, and no deposits were observed in the engine afterwards. The bag house filter was an excellent and well operating gas cleaning system. Small amounts of deposits consisting of salts and carbonates were observed in the hot gas heat exchangers. The top of...

  18. Experience with Operation of Two-Stages Fixed Bed Gasifiers

    Czech Academy of Sciences Publication Activity Database

    Skoblia, S.; Beňo, Z.; Brynda, Jiří; Pohořelý, Michael; Picek, I.

    Prague : CTU publishing house, 2015 - (Winter, F.; Hrdlička, J.), s. 42 ISBN 978-80-01-05736-0. [International Conference for Young Researchers and PhD Students /9./. Monínec (CZ), 04.05.2015-06.05.2015] R&D Projects: GA TA ČR(CZ) TA04020853 Institutional support: RVO:67985858 Keywords : two-stage biomass gasification * woog chips * gas composition Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  19. Sulfur Tolerant Magnesium Nickel Silicate Catalyst for Reforming of Biomass Gasification Products to Syngas

    Directory of Open Access Journals (Sweden)

    Scott L. Swartz

    2012-04-01

    Full Text Available Magnesium nickel silicate (MNS has been investigated as a catalyst to convert tars and light hydrocarbons to syngas (CO and H2 by steam reforming and CO2 reforming in the presence of H2S for biomass gasification process at NexTech Materials. It was observed that complete CH4 conversion could be achieved on MNS catalyst granules at 800–900 °C and a space velocity of 24,000 mL/g/h in a simulated biomass gasification stream. Addition of 10–20 ppm H2S to the feed had no apparent impact on CH4 conversion. The MNS-washcoated monolith also showed high activities in converting methane, light hydrocarbons and tar to syngas. A 1200 h test without deactivation was achieved on the MNS washcoated monolith in the presence of H2S and/or NH3, two common impurities in gasified biomass. The results indicate that the MNS material is a promising catalyst for removal of tar and light hydrocarbons from biomass gasified gases, enabling efficient use of biomass to produce power, liquid fuels and valuable chemicals.

  20. Analytical Investigations of Kinetic and Heat Transfer in Slow Pyrolysis of a Biomass Particle

    Directory of Open Access Journals (Sweden)

    S.J Ojolo

    2013-06-01

    Full Text Available The utilization of biomass for heat and power generation has aroused the interest of most researchers especially those of energy .In converting solid fuel to a usable form of energy,pyrolysis plays an integral role. Understanding this very important phenomenon in the thermochemical conversion processes and representing it with appropriate mathematical models is vital in the design of pyrolysis reactors and biomass gasifiers. Therefore, this study presents analytical solutions to the kinetic and the heat transfer equations that describe the slow pyrolysis of a biomass particle. The effects of Biot number, temperature and residence time on biomass particle decomposition were studied. The results from the proposed analytical models are in good agreement with the reported experimental results. The developed analytical solutions to the heat transfer equations which have been stated to be “analytically involved” showed average percentageerror and standard deviations 0.439 and 0.103 from the experimental results respectively as compared with previous model in literature which gives average percentage error and standard deviations 0.75 and 0.106 from the experimental results respectively. This work is of great importance in the design of some pyrolysis reactors/units and in the optimal design of the biomass gasifiers.

  1. Biomass systems

    International Nuclear Information System (INIS)

    Biofuels productions and uses should allow valorization of raw materials belonging to biomass: plants used in food utilization, ligno-cellulose plants, or by-products even wastes from animal or vegetable origin. These bioenergies are renewable energies, and their developments pass through an economical competitivity, a clean and spare production, and atmospheric emissions control of vehicles. The principal advantage of bioenergies is the reduction of fossil carbon consumption and its replacement by a renewable carbon consumption. (A.B.). 13 refs., 7 figs., 3 tabs

  2. 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...

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

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-09-30

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

  4. Tar dewpoint analyser. For application in biomass gasification product gases

    International Nuclear Information System (INIS)

    This project aims at the development of an analyser for the on-line measurement of tar dewpoints in biomass product gases. The work has been executed according to the project proposal. On basis of the specifications for the tar dewpoint analyser (TDA), an existing hydrocarbon dewpoint sensor was modified and a gas conditioning section was designed for tar dewpoint measurements. Preliminary laboratory tests with the gas conditioning section and dewpoint sensor were run to investigate the performance and fouling characteristics of the dewpoint sensor and the gas conditioning section. The TDA (gas conditioning section + sensor) was tested and validated downstream the laboratory scale BFB gasifier at ECN. Tar dewpoints between 25C and 170C could successfully be measured. After finishing the tests a pre design for a commercial analyser was made. Finally, the market for the TDA was identified and segmented in R and D groups, indirect co-combustion and stand-alone biomass gasification installations

  5. PCDDs/PCDFs, dl-PCBs and HCB in the flue gas from coal fired CFB boilers.

    Science.gov (United States)

    Grochowalski, Adam; Konieczyński, Jan

    2008-08-01

    The aim of the project was to measure the actual emissions of polychlorinated dibenzodioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (dl-PCBs) and hexachlorobenzene (HCB) from four selected power plants in Poland in order to update the national inventory of PCDDs/PCDFs emission. Relatively low PCDDs/PCDFs as well as dl-PCBs concentrations in flue gas obtained in measurements in this study for four different circulated fluidized bed (CFB) boilers indicate practical absence of any hazards caused by PCDDs/PCDFs emission from these units. The results of PCDDs/PCDFs determination obtained in this study indicate that hard coal combustion in large CFB in the four central heating plants (CHP) is not a significant source of PCDDs/PCDFs emission to the environment even if operated by co-firing of waste coal. PCDDs/PCDFs concentration in flue gases as well as emission factors were recorded in the range of 0.012-0.060 ng I-TEQ/m(n)(3) and 7.51-46.4 microg I-TEQ/TJ, respectively. Dl-PCBs concentration was practically below the LOQ=0.006 ng WHO-PCB TEQ/m(n)(3) in all experiments. HCB concentration as well as emission factors were recorded in the range of 11.5-42.0 ng/m(n)(3) and 6.19-26.7 mg/TJ, respectively, where the highest value was obtained for co-firing of waste coal, however. Obtained in this work emission factors will be used for national emission inventory purposes instead of the factors proposed by Toolkit or taken from previous measurements. However, consideration should be given to the fact that the measurements in most cases are related to single installations. Therefore, the need for further development of national factors for the power generation industry in Poland is desired. PMID:18617217

  6. Techno-economic Analysis for the Conversion of Lignocellulosic Biomass to Gasoline via the Methanol-to-Gasoline (MTG) Process

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Susanne B.; Zhu, Yunhua

    2009-05-01

    Biomass is a renewable energy resource that can be converted into liquid fuel suitable for transportation applications. As a widely available biomass form, lignocellulosic biomass can have a major impact on domestic transportation fuel supplies and thus help meet the Energy Independence and Security Act renewable energy goals (U.S. Congress 2007). With gasification technology, biomass can be converted to gasoline via methanol synthesis and methanol-to-gasoline (MTG) technologies. Producing a gasoline product that is infrastructure ready has much potential. Although the MTG technology has been commercially demonstrated with natural gas conversion, combining MTG with biomass gasification has not been shown. Therefore, a techno-economic evaluation for a biomass MTG process based on currently available technology was developed to provide information about benefits and risks of this technology. The economic assumptions used in this report are consistent with previous U.S. Department of Energy Office of Biomass Programs techno-economic assessments. The feedstock is assumed to be wood chips at 2000 metric ton/day (dry basis). Two kinds of gasification technologies were evaluated: an indirectly-heated gasifier and a directly-heated oxygen-blown gasifier. The gasoline selling prices (2008 USD) excluding taxes were estimated to be $3.20/gallon and $3.68/gallon for indirectly-heated gasified and directly-heated. This suggests that a process based on existing technology is economic only when crude prices are above $100/bbl. However, improvements in syngas cleanup combined with consolidated gasoline synthesis can potentially reduce the capital cost. In addition, improved synthesis catalysts and reactor design may allow increased yield.

  7. Research and evaluation of biomass resources/conversion/utilization systems (market/experimental analysis for development of a data base for a fuels from biomass model). Quarterly technical progress report, November 1, 1979-January 31, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Y.K.; Chen, Y.C.; Chen, H.T.; Helm, R.W.; Nelson, E.T.; Shields, K.J.; Stringer, R.P.; Bailie, R.C.

    1980-01-01

    The biomass allocation model has been developed and is undergoing testing. Data bases for biomass feedstock and thermochemical products are complete. Simulated data on process efficiency and product costs are being used while more accurate data are being developed. Market analyses data are stored for the biomass allocation model. The modeling activity will assist in providing process efficiency information required for the allocation model. Process models for entrained bed and fixed bed gasifiers based on coal have been adapted to biomass. Fuel product manufacturing costs will be used as inputs for the data banks of the biomass allocations model. Conceptual economics have been generated for seven of the fourteen process configurations via a biomass economic computer program. The PDU studies are designed to demonstrate steady state thermochemical conversions of biomass to fuels in fluidized, moving and entrained bed reactor configurations. Pulse tests in a fluidized bed to determine the effect of particle size on reaction rates and product gas composition have been completed. Two hour shakedown tests using peanut hulls and wood as the biomass feedstock and the fluidized bed reactor mode have been carried out. A comparison was made of the gas composition using air and steam - O/sub 2/. Biomass thermal profiles and biomass composition information shall be provided. To date approximately 70 biomass types have been collected. Chemical characterization of this material has begun. Thermal gravimetric, pyrogaschromatographic and effluent gas analysis has begun on pelletized samples of these biomass species.

  8. High Performance Gasification with the Two-Stage Gasifier

    DEFF Research Database (Denmark)

    Gøbel, Benny; Hindsgaul, Claus; Henriksen, Ulrik Birk;

    2002-01-01

    Based on more than 15 years of research and practical experience, the Technical University of Denmark (DTU) and COWI Consulting Engineers and Planners AS present the two-stage gasification process, a concept for high efficiency gasification of biomass producing negligible amounts of tars. In the......, air preheating and pyrolysis, hereby very high energy efficiencies can be achieved. Encouraging results are obtained at a 100 kWth laboratory facility. The tar content in the raw gas is measured to be below 25 mg/Nm3 and around 5 mg/Nm3 after gas cleaning with traditional baghouse filter. Furthermore...

  9. Removal and Conversion of Tar in Syngas from Woody Biomass Gasification for Power Utilization Using Catalytic Hydrocracking

    OpenAIRE

    Jiu Huang; Klaus Gerhard Schmidt; Zhengfu Bian

    2011-01-01

    Biomass gasification has yet to obtain industrial acceptance. The high residual tar concentrations in syngas prevent any ambitious utilization. In this paper a novel gas purification technology based on catalytic hydrocracking is introduced, whereby most of the tarry components can be converted and removed. Pilot scale experiments were carried out with an updraft gasifier. The hydrocracking catalyst was palladium (Pd). The results show the dominant role of temperature and flow rate. At a cons...

  10. 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

  11. Simulasi dan Eksperimental Isothermal Aliran Eksternal Resirkulasi pada Up-Draft Gasifier

    Directory of Open Access Journals (Sweden)

    Fajri Vidian

    2011-01-01

    Full Text Available Gasification process at updraft gasifier produces greater amount of tar than other type of gasifier. To reduce tar at updraft gasifier, the pirolysis gas will be re-circulated to combustion zone and to exhaust gas from reduction zone. Recirculation of pirolysis gas to combustion zone can be carried out by using ejector. Ejector is an equipment used to inject the secondary fluid flow by the movement of momentum and energy from high speed primary flow (jet. The research conducted with isothermal 3D simulation using CFD and experimental investigation of recirculation flow using ejector at updraft gasifier. Ejector velocity for simulation and experimentation is constant at 0.6 m/s. Ejector’s nozzle exit position (NXP direction will be varied. The goal of this research is to obtain information of optimal nozzle exit position for producing maximum velocity of gas recirculation. The result of simulation and experiment shows that the change of nozzle exit position direction to – x axis from zero point, it will give maximum velocity of gas recirculation flow with the optimum position of nozzle exit position at the range of -3 to -4 cm from zero point.

  12. Test of pyrolysis gasifier stoves in two institutional kitchens in Uganda

    DEFF Research Database (Denmark)

    Wendelbo, Pall; Nielsen, Per Sieverts

    institutional cooking places can be used to prepare the local food and that it saves at least 2/3 of the wood compared with the use of traditional three stone stoves. Furthermore, the use of the gasifier units, which burn without smoke, reduces the exposure to smoke considerably; however, this is only evaluated...

  13. Numerical Investigation on Performance of Coal Gasifier of 150kW under Various Injection Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hyeongyeong; Suh, Jaeseung [Hannam Univ., Daejeon (Korea, Republic of); Lho, Taihyeop [National Fusion Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Integrated coal gasification combined cycle (IGCC) has gained a lot of interest because they can produce cleaner gaseous fuels such as hydrogen, carbon monoxide and methane. This study focuses on the 150kW gasifier which is used in the National Fusion Research Institute (NFRI) plant. It is a fusion plasma technology to existing coal gasifier for better efficiency of low-carbon fuels. The cold gas is generated by reacting oxidants to coal with plasma technology of high temperature. The purpose of this study is to get the highest cold gas efficiency varied according to oxidant/coal injection amount, location and feeding gas. It is considerably complicated and expensive that cold gas efficiency is experimentally compared for all cases. It is possible to predict flow patterns, tracks of particles, combustion characteristics, temperature distributions and chemical distributions using the commercial CFD solver ANSYS/FLUENT. This study has numerical investigation for the phenomena of coal gasification for coal gasifier of 150kW at various operating conditions. The results are summarized in table 6. The air as feeding gas is more efficient than carbon dioxide, and the amount of coal that is important to find the appropriate value for the capacity of the gasifier than strictly greater.

  14. Modeling of flow conditions in down draft gasifiers using tin film models

    DEFF Research Database (Denmark)

    Jensen, Torben Kvist; Gøbel, Benny; Henriksen, Ulrik Birk

    2003-01-01

    In order to examine how an inhomogeneous char bed affects the gas flow through the bed, a dynamic model have been developed to describe the flow distribution in a down draft gasifier. The gas flow distribution through the bed was determined using a thin film model approach. The temperatures in the...

  15. Numerical Investigation on Performance of Coal Gasifier of 150kW under Various Injection Conditions

    International Nuclear Information System (INIS)

    Integrated coal gasification combined cycle (IGCC) has gained a lot of interest because they can produce cleaner gaseous fuels such as hydrogen, carbon monoxide and methane. This study focuses on the 150kW gasifier which is used in the National Fusion Research Institute (NFRI) plant. It is a fusion plasma technology to existing coal gasifier for better efficiency of low-carbon fuels. The cold gas is generated by reacting oxidants to coal with plasma technology of high temperature. The purpose of this study is to get the highest cold gas efficiency varied according to oxidant/coal injection amount, location and feeding gas. It is considerably complicated and expensive that cold gas efficiency is experimentally compared for all cases. It is possible to predict flow patterns, tracks of particles, combustion characteristics, temperature distributions and chemical distributions using the commercial CFD solver ANSYS/FLUENT. This study has numerical investigation for the phenomena of coal gasification for coal gasifier of 150kW at various operating conditions. The results are summarized in table 6. The air as feeding gas is more efficient than carbon dioxide, and the amount of coal that is important to find the appropriate value for the capacity of the gasifier than strictly greater

  16. Application of Direct Ignition Technology with Minimum Gasified Oil in Lignite-Fired Boiler

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ The firing is in the stsble condition and the rate of oil saving comes up to 64%,after Fularji Power Plant adoted the technology of minimun gasified oil igniting pulverized lignite directly and the technology of multistage coal combustion withenergy amplified stage by stage.

  17. Method of generating electricity using an endothermic coal gasifier and MHD generator

    Science.gov (United States)

    Marchant, David D.; Lytle, John M.

    1982-01-01

    A system and method of generating electrical power wherein a mixture of carbonaceous material and water is heated to initiate and sustain the endothermic reaction of carbon and water thereby providing a gasified stream containing carbon monoxide, hydrogen and nitrogen and waste streams of hydrogen sulfide and ash. The gasified stream and an ionizing seed material and pressurized air from a preheater go to a burner for producing ionized combustion gases having a temperature of about 5000.degree. to about 6000.degree. F. which are accelerated to a velocity of about 1000 meters per second and passed through an MHD generator to generate DC power and thereafter through a diffuser to reduce the velocity. The gases from the diffuser go to an afterburner and from there in heat exchange relationship with the gasifier to provide heat to sustain the endothermic reaction of carbon and water and with the preheater to preheat the air prior to combustion with the gasified stream. Energy from the afterburner can also be used to energize other parts of the system.

  18. 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

  19. Biomass gasification with preheated air: Energy and exergy analysis

    Directory of Open Access Journals (Sweden)

    Karamarkovic Rade M.

    2012-01-01

    Full Text Available Due to the irreversibilities that occur during biomass gasification, gasifiers are usually the least efficient units in the systems for production of heat, electricity, or other biofuels. Internal thermal energy exchange is responsible for a part of these irreversibilities and can be reduced by the use of preheated air as a gasifying medium. The focus of the paper is biomass gasification in the whole range of gasification temperatures by the use of air preheated with product gas sensible heat. The energetic and exergetic analyses are carried with a typical ash-free biomass feed represented by CH1.4O0.59N0.0017 at 1 and 10 bar pressure. The tool for the analyses is already validated model extended with a heat exchanger model. For every 200 K of air preheating, the average decrease of the amount of air required for complete biomass gasification is 1.3% of the amount required for its stoichiometric combustion. The air preheated to the gasification temperature on the average increases the lower heating value of the product gas by 13.6%, as well as energetic and exergetic efficiencies of the process. The optimal air preheating temperature is the one that causes gasification to take place at the point where all carbon is consumed. It exists only if the amount of preheated air is less than the amount of air at ambient temperature required for complete gasification at a given pressure. Exergy losses in the heat exchanger, where the product gas preheats air could be reduced by two-stage preheating.

  20. Pressure-drop predictions in a fixed-bed coal gasifier

    Energy Technology Data Exchange (ETDEWEB)

    Adam Luckos; John R. Bunt [Sasol Technology, Sasolburg (South Africa). R& amp; D Division

    2011-03-15

    In the Sasol Synfuels plant in Secunda, Sasol-Lurgi fixed-bed dry-bottom gasifiers are used for the conversion of low-grade bituminous coals to synthesis gas (syngas). The gasifiers are fed with lump coal having a particle size in the range from 5 to 100 mm. Operating experience shows that the average particle size and particle-size distribution (PSD) of feed coal, char and ash influence the pressure drop across the bed and the gas-flow distribution within the bed. These hydrodynamic phenomena are responsible for stable gasifier operation and for the quality and production rate of the syngas. The counter-current operation produces four characteristic zones in the gasifier, namely, drying, de-volatilization, reduction and combustion. The physical properties of the solids (i.e. average particle size, PSD, sphericity and density) are different in each of these zones. Similarly, the chemical composition of the syngas, its properties (temperature, density and viscosity) and superficial velocity vary along the height of the bed. The most popular equation used to estimate the pressure drop in packed beds is that proposed by Ergun. The Ergun equation gives good predictions for non-reacting, isothermal packed beds made of uniformly sized, spherical or nearly spherical particles. In the case of fixed-bed gasifiers, predictions by the Ergun equation based on the average or inlet values of bed and gas flow parameters are unsatisfactory because the bed structure and gas flow vary significantly in the different reaction zones. In this study, the Ergun equation is applied to each reaction zone separately. The total pressure drop across the bed is then calculated as the sum of pressure drops in all zones. It is shown that the total pressure drop obtained this way agrees better with the measured result. 44 refs., 2 tabs.

  1. Secondary reactions of tar during thermochemical biomass conversion[Dissertation 14341

    Energy Technology Data Exchange (ETDEWEB)

    Morf, P.O.

    2001-07-01

    This dissertation submitted to the Swiss Federal Institute of Technology in Zurich presents and discusses the results obtained during the examination of the processes involved in the formation and conversion of tar in biomass gasification plant. Details are given on the laboratory reactor system used to provide separated tar production and conversion for the purposes of the experiments carried out. The results of analyses made of the tar and the gaseous products obtained after its conversion at various temperatures are presented. The development of kinetic models using the results of the experiments that were carried out is described. The results of the experiments and modelling are compared with the corresponding results obtained using a full-scale down-draft, fixed-bed gasifier. The author is of the opinion that the reaction conditions found in full-scale gasifiers can be well simulated using heterogeneous tar conversion experiments using the lab reactor system.

  2. Development Of An Acoustice Sensor For On-Line Gas Temperature Measurement In Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Peter Ariessohn; Hans Hornung

    2006-10-01

    This project was awarded under U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL) Program Solicitation DE-PS26-02NT41422 and specifically addresses Technical Topical Area 2 - Gasification Technologies. The project team includes Enertechnix, Inc. as the main contractor and ConocoPhillips Company as a technical partner, who also provides access to the SG Solutions Gasification Facility (formerly Wabash River Energy Limited), host for the field-testing portion of the research. The objective of this project was to adapt acoustic pyrometer technology to make it suitable for measuring gas temperature inside a coal gasifier, to develop a prototype sensor based on this technology, and to demonstrate its performance through testing on a commercial gasifier. The project was organized in three phases, each of approximately one year duration. The first phase consisted of researching a variety of sound generation and coupling approaches suitable for use with a high pressure process, evaluation of the impact of gas composition variability on the acoustic temperature measurement approach, evaluation of the impact of suspended particles and gas properties on sound attenuation, evaluation of slagging issues and development of concepts to deal with this issue, development and testing of key prototype components to allow selection of the best approaches, and development of a conceptual design for a field prototype sensor that could be tested on an operating gasifier. The second phase consisted of designing and fabricating a series of prototype sensors, testing them in the laboratory, and developing a conceptual design for a field prototype sensor. The third phase consisted of designing and fabricating the field prototype, and testing it in the lab and in a commercial gasifier to demonstrate the ability to obtain accurate measurements of gas temperature in an operating gasifier. This report describes all of the activities conducted during the project and

  3. Biomass torrefaction mill

    Science.gov (United States)

    Sprouse, Kenneth M.

    2016-05-17

    A biomass torrefaction system includes a mill which receives a raw biomass feedstock and operates at temperatures above 400 F (204 C) to generate a dusty flue gas which contains a milled biomass product.

  4. Biomass steam gasification with in-situ CO{sub 2} capture for enriched hydrogen gas production: a reaction kinetics modelling approach

    Energy Technology Data Exchange (ETDEWEB)

    Abrar Inayat, A.; Ahmad, M. M.; Yusup, S.; Mutalib, M. I. A. [Department of Chemical Engineering, Universiti Teknologi Petronas, Bandar Seri Iskandar, 31750 Tronoh (Malaysia)

    2010-08-15

    Due to energy and environmental issues, hydrogen has become a more attractive clean fuel. Furthermore, there is high interest in producing hydrogen from biomass with a view to sustainability. The thermochemical process for hydrogen production, i.e. gasification, is the focus of this work. This paper discusses the mathematical modeling of hydrogen production process via biomass steam gasification with calcium oxide as sorbent in a gasifier. A modelling framework consisting of kinetics models for char gasification, methanation, Boudouard, methane reforming, water gas shift and carbonation reactions to represent the gasification and CO{sub 2} adsorption in the gasifier, is developed and implemented in MATLAB. The scope of the work includes an investigation of the influence of the temperature, steam/biomass ratio and sorbent/biomass ratio on the amount of hydrogen produced, product gas compositions and carbon conversion. The importance of different reactions involved in the process is also discussed. It is observed that hydrogen production and carbon conversion increase with increasing temperature and steam/biomass ratio. The model predicts a maximum hydrogen mole fraction in the product gas of 0.81 occurring at 950 K, steam/biomass ratio of 3.0 and sorbent/biomass ratio of 1.0. In addition, at sorbent/biomass ratio of 1.52, purity of H{sub 2} can be increased to 0.98 mole fraction with all CO{sub 2} present in the system adsorbed. (authors)

  5. 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

  6. Experimental setup for combustion characteristics in a diesel engine using derivative fuel from biomass

    International Nuclear Information System (INIS)

    Reciprocating engines are normally run on petroleum fuels or diesel fuels. Unfortunately, energy reserves such as gas and oil are decreasing. Today, with renewable energy technologies petroleum or diesel can be reduced and substituted fully or partly by alternative fuels in engine. The objective of this paper is to setup the experimental rig using producer gas from gasification system mix with diesel fuel and fed to a diesel engine. The Yanmar L60AE-DTM single cylinder diesel engine is used in the experiment. A 20 kW downdraft gasifier has been developed to produce gas using cut of furniture wood used as biomass source. Air inlet of the engine has been modified to include the producer gas. An AVL quartz Pressure Transducer P4420 was installed into the engine head to measure pressure inside the cylinder of the engine. Several test were carried out on the downdraft gasifier system and diesel engine. The heating value of the producer gas is about 4 MJ/m3 and the specific biomass fuel consumption is about 1.5 kg/kWh. Waste cooking oil (WCO) and crude palm oil (CPO) were used as biomass fuel. The pressure versus crank angle diagram for using blend of diesel are presented and compared with using diesel alone. The result shows that the peak pressure is higher. The premixed combustion is lower but have higher mixing controlled combustion. The CO and NOx emission are higher for biomass fuel

  7. 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)

  8. Techno-Economic Study of Adsorption Processes for Pre-Combustion Carbon Capture at a Biomass CHP Plant

    OpenAIRE

    Oreggioni, Gabriel David; Friedrich, Daniel; Brandani, Stefano; Ahn, Hyungwoong

    2014-01-01

    An exemplary 10 MWth biomass CHP plant with a FICFB (Fast Internally Circulating Fluidised Bed) gasifier and Jenbacher type 6 gas engine was simulated to estimate the power and thermal outputs. The biomass-fuelled CHP plant was modified for carbon capture using either adsorption or amine process. It was found that a two-stage, two-bed PVSA (Pressure Vacuum Swing Adsorption) unit applied to syngas stream for pre-combustion capture spent less specific energy per captured CO2 than a conventional...

  9. Development of an Acoustic Sensor On-Line Gas Temperature Measurement in Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Peter Ariessohn

    2008-06-30

    This project was awarded under U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL) Program Solicitation DE-PS26-02NT41422 and specifically addresses Technical Topical Area 2 - Gasification Technologies. The project team includes Enertechnix, Inc. as the main contractor and ConocoPhillips Company as a technical partner, who also provides access to the SG Solutions Gasification Facility (formerly Wabash River Energy Limited), host for the field-testing portion of the research. The objective of this project was to adapt acoustic pyrometer technology to make it suitable for measuring gas temperature inside a coal gasifier, to develop a prototype sensor based on this technology, and to demonstrate its performance through testing on a commercial gasifier. The project was organized in three phases, each of approximately one year duration. The first phase consisted of researching a variety of sound generation and coupling approaches suitable for use with a high pressure process, evaluation of the impact of gas composition variability on the acoustic temperature measurement approach, evaluation of the impact of suspended particles and gas properties on sound attenuation, evaluation of slagging issues and development of concepts to deal with this issue, development and testing of key prototype components to allow selection of the best approaches, and development of a conceptual design for a field prototype sensor that could be tested on an operating gasifier. The second phase consisted of designing and fabricating a series of prototype sensors, testing them in the laboratory, and developing a conceptual design for a field prototype sensor. The third phase consisted of designing and fabricating the field prototype, and testing it in the lab and in a commercial gasifier to demonstrate the ability to obtain accurate measurements of gas temperature in an operating gasifier. Following the completion of the initial 3 year project, several continuations

  10. Biomass treatment method

    Science.gov (United States)

    Friend, Julie; Elander, Richard T.; Tucker, III; Melvin P.; Lyons, Robert C.

    2010-10-26

    A method for treating biomass was developed that uses an apparatus which moves a biomass and dilute aqueous ammonia mixture through reaction chambers without compaction. The apparatus moves the biomass using a non-compressing piston. The resulting treated biomass is saccharified to produce fermentable sugars.

  11. Unified modeling and feasibility study of novel green pathway of biomass to methanol/dimethylether

    International Nuclear Information System (INIS)

    Graphical abstract: Biomass-to-methanol/DME synthesis process layout. - Highlights: • Design, simulation, and control of the direct-storage concentrating solar plant. • Feasibility study of the low-temperature biomass gasification. • First-principles model of biomass gasifier. • First-principles model of one-step methanol/dimethylether synthesis reactor. • Integrated numerical platform for total plant simulation. - Abstract: A novel, integrated and unified process is proposed, modeled and studied for converting biomass to methanol (MeOH)/dimethylether (DME) to demonstrate its feasibility and applicability for the global industrial sector. The unified process consists of a concentrating solar power (CSP) plant, which supplies the produced steam to the biomass gasification process as well as to the downstream conversions to chemical commodities and energy carriers. To preserve the effectiveness of the biomass gasification with low-temperature solar-powered generated steam (approximately 400–410 °C), the gasification process is studied by means of a multi-complex (multi-scale, multi-phase, and multi-component) model and adapted to the novel proposed conditions. The syngas generated in the biomass gasification unit is then converted into MeOH/DME by means of one-step synthesis technology to improve the overall yield of the biomass-to-methanol process

  12. Chronic and reproduction studies in rats exposed to gasifier ash leachates.

    Science.gov (United States)

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

    1982-01-01

    Ash from the coal gasification process contains a broad spectrum of elements which through leaching (gasifier ash leachates) may enter into the environment. The health effect of such leachates i.e. complex mixtures of inorganic elements is insufficiently known. We investigated the effect of gasifier ash leachates in a chronic-(9-month) and in a three-generation reproduction study. The leachates were prepared weekly by water extraction of ash from a Lurgi coal gasification plant in Yugoslavia, and given to experimental animals instead of drinking water. In the chronic experiment exposed animals showed no changes in mortality rate, haematological findings, concentration of Fe, Zn, Mn in kidneys, liver, testicles and femur, as well as in femur composition and morphometry, gross pathology and organ histology. In the reproduction study the number of pregnancies, weight and number of newborns, and concentration of Fe, Zn, Mn in carcasses of sucklings were the same in control and experimental animals. PMID:7063833

  13. Decomposition of tar in gas from updraft gasifier by thermal cracking

    DEFF Research Database (Denmark)

    Brandt, Peder; Henriksen, Ulrik Birk

    2000-01-01

    Continuing earlier work with tar reduction by partial oxidation of pyrolysis gas [1] thermal cracking has been evaluated as a gas cleaning process. The work has been focusing on cleaning gas from updraft gasifiers, and the long term purpose is to develop a tar cleaning unit based on thermal...... low as 15 mg/Nm3 was obtained on gas from an updraft gasifier. The lower heating value of the cleaned gas was 6.0 MJ/Nm3, and the energy content of the non condensable gasses was 19% higher than before cracking....... was 1200, 1250 and 1290°C, and the residence time at this temperature was 0.5 second. The measurements show that at the selected residence time of 0.5 second, the gas flow in a thermal tar cracking unit has to be heated to at least 1250°C to achieve sufficient tar cleaning. At 1290°C, a tar content as...

  14. Thermodynamic analyses of a biomass integrated fired combined cycle

    International Nuclear Information System (INIS)

    A biomass integrated fired combined cycle (BIFCC) is proposed and examined with energy and exergy analyses. A focal point is the biomass gasification process, for which four different biomasses are examined. The fuel in the bottoming cycle is a biomass while the topping cycle fuel is natural gas. The analyses consider a range of compressor pressure ratios (6–24), gas turbine inlet temperatures (1300–1500 K), heat recovery steam generator (HRSG) inlet temperatures (840–940 K) and molar natural gas to biomass ratios (0.05–1.50). The energy efficiency is compared when the cycle uses natural gas, or natural gas and biomass (of various kinds). The efficiency is seen to be maximized at an optimum pressure ratio, which depends on the gas turbine and HRSG inlet temperatures. Increasing the gas turbine and decreasing the HRSG inlet temperatures leads to in an increase in energy and exergy efficiencies for the cycle. The performance of an 80-MW capacity plant is investigated for three cases, with optimum pressure ratios and various operating parameters. The most advantageous performance among the three cases, for which the energy and exergy efficiencies are 53.16 and 48.39% respectively, is achieved when the turbine inlet temperature is 1500 K, the HRSG inlet temperature is 840 K and the compressor pressure ratio is 14. -- Highlights: • A gas turbine combined cycle with gasified biomass firing is analyzed. • Thermodynamic analysis considers first and second law analyses. • Thermal efficiency peaks at an optimum cycle pressure ratio (about 10–14). • Three sets of operating parameters are considered in a detailed case study. • One of three cases is more efficient from energy and exergy viewpoints

  15. Activated carbon produced from Sasol-Lurgi gasifier pitch and its application as electrodes in supercapacitors

    OpenAIRE

    A. Alonso; Ruiz Ruiz, Vanesa; Blanco Rodríguez, Clara; Santamaría Ramírez, Ricardo; Granda Ferreira, Marcos; Menéndez López, Rosa María; Jager, S.G.E. de

    2006-01-01

    [EN] A pyrolysis product derived from Sasol-Lurgi gasifier pitch was activated using different proportions of KOH. The increase of the amount of KOH used for activation caused the activation degree of the carbons to increase very significantly. The activated carbons obtained using lower amounts of KOH were mainly microporous, while the amount of mesopores developed in the samples progressively increased for the carbons activated with higher proportions of KOH. The gravimetric specific capacit...

  16. Modeling of a Pressurized Entrained-Flow Coal Gasifier for Power Plant Simulation

    OpenAIRE

    Krüger, Michael

    2014-01-01

    Now and in the mid-term future, coal remains an important energy source for electricity generation for reasons of energy supply security and economics. The expectation to get low CO2-emissions and high plant efficiencies, particularly independently of coal quality, makes coal gasification an essential part of numerous innovative power plant concepts. For that reason, simplified and flexible models for coal gasifiers are needed, which can be implemented easily in complex power plant system sim...

  17. Modeling of a pressurized entrained-flow coal gasifier for power plant simulation

    OpenAIRE

    Krüger, Michael

    2014-01-01

    Now and in the mid-term future, coal remains an important energy source for electricity generation for reasons of energy supply security and economics. The expectation to get low CO2-emissions and high plant efficiencies, particularly independently of coal quality, makes coal gasification an essential part of numerous innovative power plant concepts. For that reason, simplified and flexible models for coal gasifiers are needed, which can be implemented easily in complex power plant system sim...

  18. 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...

  19. Pyrolysis gasification of dried sewage sludge in a combined screw and rotary kiln gasifier

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Young Nam; Kim, Seong Cheon [BK21 Team for Hydrogen Production, Department of Environmental Engineering, Chosun University, 375 Seosuk-dong, Dong-gu, Gwangju 501-759 (Korea, Republic of); Yoshikawa, Kunio [Frontier Research Center, Tokyo Institute of Technology, G5-8, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502 (Japan)

    2011-04-15

    A pyrolysis gasifier, with carbonization and activation steps, was developed to convert dried sludge into activated char and gas fuel energy. To determine the optimal driving conditions, parametric investigations were conducted on the amount of steam input, pyrolysis gasifier temperature and moisture content in the dried sludge. The optimal conditions for the dried sludge were found to be a steam input of 10 mL/min, gasifier temperature of 820 C and moisture content of 11% with a holding time in the pyrolysis gasifier of 1 h. The specific area of the activated char was 40.1 m{sup 2}/g, with an average pore diameter and volume of 63.49 Aa and 0.2354 cm{sup 3}/g, respectively. The pyrolysis gases were H{sub 2} (34.1%), CO (18.6%), CH{sub 4} (8.5%) and CO{sub 2} (8%). The higher heating value for the pyrolysis gas was 10,107 kJ/N m{sup 3}. To determine the tar adsorption characteristics, a benzene adsorption test was conducted using a fixed bed adsorption tower (H/D = 2, GHSV = 1175/h). The saturation point of the activated char was found after 45 min, and the amount of adsorption was 140 mg/g. Therefore, the pyrolysis gasification of sewage sludge can produce activated char which can be used to reduce tar, and gasification gas which can be utilized as a high enthalpy gas fuel. (author)

  20. Carbon formation and metal dusting in hot-gas cleanup systems of coal gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Tortorelli, P.F.; DeVan, H.J.; Judkins, R.R. [and others

    1995-06-01

    The product gas resulting from the partial oxidation of carboniferous materials in a gasifier consists predominantly of CO, CO{sub 2}, H{sub 2}, H{sub 2}O, CH{sub 4}, and, for air-blown units, N{sub 2} in various proportions at temperatures ranging from about 400 to 1000{degree}C. Depending on the source of the fuel, smaller concentrations of H{sub 2}S, COS, and NH{sub 3} can also be present. The gas phase is typically characterized by high carbon and sulfur, but low oxygen, activities and, consequently, severe degradation of the structural and functional materials used in the gasifier can occur. Therefore, there are numerous concerns about materials performance in coal gasification systems, particularly at the present time when demonstration-scale projects are in or nearing the construction and operation phases. This study focused on the subset of materials degradation phenomena resulting from carbon formation and carburization processes, which are related to potential operating problems in certain gasification components and subsystems. More specifically, it examined the current state of knowledge regarding carbon deposition and a carbon-related degradation phemonenon known as metal dusting as they affect the long-term operation of the gas clean-up equipment downstream of the gasifier and addressed possible means to mitigate the degradation processes. These effects would be primarily associated with the filtering and cooling of coal-derived fuel gases from the gasifier exit temperature to as low as 400{degree}C. However, some of the consideratins are sufficiently general to cover conditions relevant to other parts of gasification systems.

  1. Multifluid modeling of the desulfurization process within a bubbling fluidized bed coal gasifier

    OpenAIRE

    Armstrong, L-M.; Gu, Sai; Luo, K. H.; P Mahanta

    2013-01-01

    The desulfurization process to a two-dimensional (2-D) and three-dimensional (3-D) Eulerian-Eulerian computational fluid dynamic (CFD) model of a coal bubbling fluidized gasifier is introduced. The desulfurization process is important for the reduction of harmful SOx emissions; therefore, the development of a CFD model capable of predicting chemical reactions involving desulfurization is key to the optimization of reactor designs and operating conditions. To model the process, one gaseous pha...

  2. 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

  3. Development of a sugar cane residue feeding system for a cyclone gasifier

    Energy Technology Data Exchange (ETDEWEB)

    Gabra, M.; Salman, H.; Kjellstroem, B. [Lulea University of Technology, (Sweden). Energy Technology Centre in Pitea

    1998-12-31

    For the smooth and continuous operation of a cyclone gasifier, the fuel must be fed continuously and without interruption or large fluctuations. A feeding system for bagasse/cane trash powder was therefore designed, built and tested. It consisted of a feeding bin with four feeder screws in the bottom which deliver the fuel to two downcomers from which the fuel is injected by steam into the gasifier. During the first tests, the low bulk density and cohesive characteristics of a crushed bagasse/cane trash power were found to cause an accumulation of the fuel in the feeding system, creating difficulties for the flow into the gasifier. In addition, once the flow of the crushed bagasse/cane trash powder is interrupted by a build-up in the downcomer channels, the crushed bagasse/cane trash powder becomes progressively compacted into a dense structure, resulting in blockage of the discharge. It was found possible to eliminate this problem by changing the shape of the slivers of the crushed bagasse/cane trash powder to render them more homogeneous. This was achieved by pelletizing the crushed bagasse or cane trash before grinding it to powder. (author)

  4. A simple process modelling for a dry-feeding entrained bed coal gasifier

    Energy Technology Data Exchange (ETDEWEB)

    Lee, H.; Choi, S.; Paek, M. [Korean Advanced Institute of Science & Technology, Taejon (Republic of Korea). Dept. of Mechanical Engineering

    2011-07-01

    A dry-feeding entrained bed coal gasifier was numerically modelled by simultaneously solving the rate equations for chemical reactions of the solid and gas phases. This model describes simplified physical and chemical processes in the entrained bed coal gasifier. Chemical reaction processes for coal gasification and combustion are considered along with the simplified gas flow passage in the reactor, so that progress of reactions at the designated spatial location is represented. Gasification phenomena of coal particles were separated into devolatilization, gas-phase, and solid-phase reactions. Coal gasifier geometry was simplified to a pseudo-two-dimensional (pseudo-2D) reactor model based on the 1D plug flow concept. The dimension in the pseudo-2D model was conceptually divided by considering the recirculation effect. As a result, carbon conversion, cold gas efficiency, and temperature distribution were obtained at variable oxygen to coal mass ratio, steam to coal mass ratio, and operating pressure. Operating conditions could be appropriately controlled by knowing the degree of reaction in the reactor.

  5. Combustion properties of biomass residues rich in phosphorus

    Energy Technology Data Exchange (ETDEWEB)

    Piotrowska, P.

    2012-07-01

    The currently-used sources of biomass are limited so new ones are required in order to meet the European Union target and to satisfy the constantly-increasing demand for energy. This is why energy recovery from residues or waste derived fuels has been given considerable attention over recent years. The residues generated during the production of biofuels for transportation are often the main stream from the production plant. Proper allocation of the residues could significantly improve the sustainability of the production process resulting in high greenhouse gas emission savings and improvement in their profitability. Energy recovery could be one application, among others, for the residues. The objective of this study was to investigate the combustion behaviour of four residues from the production of biofuels for transportation. The residues of interest were: rapeseed cake, palm kernel cake, dried distillers' grains with solubles, and fermented sewage sludge. A wide range of methods of laboratory to semi-industrial scale was applied in order to define the main challenges, related to the fluidized bed combustion of these residues. All residues were characterized by means of laboratory methods. The residues differ substantially in their composition compared to more traditional biomass fuels. Their common property is a high concentration of phosphorus. Until recently, phosphorus was considered a negligible element for ash chemistry due to its low concentrations. Rapeseed cake was further studied, as an example of phosphorus-rich fuel, during bench-scale bubbling fluidized bed (BFB) and semi-industrial scale circulating fluidized bed (CFB) combustion experiments. Rapeseed cake, with phosphorus and alkali metals dominating its ash chemistry, led to defluidization at approximately 800 deg C. Bed sintering during fluidized bed combustion of pure rapeseed cake followed a non-reactive mechanism. This mechanism is controlled by the stickiness of fuel-derived ash

  6. Desulfurization characteristics of rapidly hydrated sorbents with various adhesive carrier particles for a semidry CFB-FGD system.

    Science.gov (United States)

    You, Changfu; Li, Yuan

    2013-03-19

    Semidry flue gas desulfurization (FGD) experiments were conducted using rapidly hydrated sorbents with four different adhesive carrier particles: circulation ash from a circulating fluidized bed boiler (CFBB circulation ash), fly ash from the first electrical field of the electrostatic precipitator of a circulating fluidized bed boiler (CFBB ESP ash), fly ash from a chain boiler (chain boiler ash), and river sand smaller than 1 mm. The influences of various adhesive carrier particles and operating conditions on the desulfurization characteristics of the sorbents were investigated, including sprayed water, reaction temperature, and the ratio of calcium to sulfur (Ca/S). The experimental results indicated that the rapidly hydrated sorbents had better desulfurization characteristics by using adhesive carrier particles which possessed better pore, adhesion, and fluidization characteristics. The desulfurization efficiency of the system increased as the reaction temperature decreased, it improved from 35% to 90% as the mass flow rate of the sprayed water increased from 0 to 10 kg/h, and it increased from 65.6% to 82.7% as Ca/S increased from 1.0 to 2.0. Based on these findings, a new semidry circulating fluidized bed (CFB)-FGD system using rapidly hydrated sorbent was developed. Using the rapidly hydrated sorbent, this system uses a cyclone separator instead of an ESP or a bag filter to recycle the sorbent particles, thereby decreasing the system flow resistance, saving investment and operating costs of the solids collection equipment. PMID:23398211

  7. The correlation based zonal method and its application to the back pass channel of oxy/air-fired CFB boiler

    International Nuclear Information System (INIS)

    A set of correlations for direct exchange area (DEA) between zones are presented. The correlations are simpler and much faster than the classical method used for DEA calculations in zone method. Additionally a unique form of correlation supports both singular and non-singular DEA calculation and no extra effort for non-singular cases is needed. Using the new correlations, the correlation based zone method (CBZM) is introduced and validated by several benchmarks. The CBZM results were in excellent agreement with the benchmark solutions. As an application case, by using the CZBM the gray and non-gray radiative heat transfer has been analyzed in a large back pass channel of a CFB boiler for the case of air and oxygen-fired combustion scenarios. The effect of the spectral radiative behavior of combustion gases on the predicted radiative heat fluxes on the walls is addressed. The effect of combustion scenario on the operation of the unit is also discussed. - Highlights: • Efficient correlations for DEA calculation are presented. • The gray and non-gray correlation based zone method is introduced. • The model is validated against several 3D benchmarks. • The effect of non-gray radiation in a large scale back pass channel is addressed. • The effect of combustion scenario on radiation in back pass channel is reported

  8. Mechanism study on the influence of in situ SOx removal on N2O emission in CFB boiler

    Science.gov (United States)

    Wu, Lingnan; Qin, Wu; Hu, Xiaoying; Dong, Changqing; Yang, Yongping

    2015-04-01

    The influence of in situ deSOx process on N2O emission in CFB boiler was studied using density functional theory calculations. The competitive adsorption of SO2 and N2O on pure CaO (1 0 0) surface was first studied and the reaction priority was determined. Results showed that SO2 was more likely to adsorb on CaO (1 0 0) surface O anion site, which hindered the catalytic decomposition of N2O on CaO (1 0 0) surface and sulfurized the CaO (1 0 0) surface under reducing atmosphere. Then a partially sulfurized CaO (1 0 0) surface was established to study the catalytic activity of deSOx reaction intermediate on N2O decomposition. The O atom transfer process and the surface recovery process were two key steps for N2O decomposition and the rate-determining step was the latter one. The sulfurization of the surface could deactivate its catalytic activity on N2O decomposition compared with pure CaO (1 0 0) surface but it was still better than that of pure CaS (1 0 0) surface. The free Gibbs energy was calculated to incorporate the temperature dependence of respective reactions. When temperature was higher than 373 K, the surface recovery was more likely to proceed via the LH route.

  9. Experimental investigation of small-scale gasification of woody biomass

    Energy Technology Data Exchange (ETDEWEB)

    Barrio, Maria

    2002-05-01

    A small-scale stratified down draft gasifier has been built and operated under stable conditions using wood pellets as fuel and air as gasification agent. The problems observed during the preliminary experiments have been described and explained; they are mainly related to the stability of the process. The stable operation of the gasifier has been characterised by the gas composition and the product gas tar and particle content. The biomass feeding rate has varied between 4,5 and 6,5 kg/h. The CO content of the product gas (23-26 % vol.) is higher than in similar gasifiers and the H{sub 2} content has been found to vary between 14 and 16 % vol. The tar content in the product gas (Ca. 3 g/Nm{sup 3}) is rather high compared with similar gasifiers. The temperature profile, together with other relevant parameters like the air-excess ratio, the air to fuel ratio and gas to fuel ratio have been calculated. The experiments show that the air excess ratio is rather constant, varying between 0,25 and 0,3. Experiments have been conducted with a gas engine using mixtures of CH{sub 4}, CO, H{sub 2}, CO{sub 2} and N{sub 2} as a fuel. NO{sub x} and CO emissions are analysed. The char gasification process has been studied in detail by means of Thermogravimetric Analysis. The study comprises the chemical kinetics of the gasification reactions of wood char in CO{sub 2} and H{sub 2}O, including the inhibition effect of CO and H{sub 2}. A kinetic model based on Langmuir-Hinshelwood kinetics has been found which relates the mass loss rate to the temperature, gas composition and degree of conversion for each reaction. The ratio CO/CO{sub 2} has been found to be a relevant parameter for reactivity. The gasification experiments in mixtures of CO{sub 2} and H{sub 2}O give reasons to believe that the rate of desorption for the complex C(O) varies depending on the gas mixture surrounding the char. It has been found that if the experimental data are obtained from separate H{sub 2}O/N{sub 2

  10. Small-Scale Coal-Biomass to Liquids Production Using Highly Selective Fischer-Tropsch Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Gangwal, Santosh K. [Southern Research Institute, Durham, NC (United States); McCabe, Kevin [Southern Research Institute, Durham, NC (United States)

    2015-04-30

    The research project advanced coal-to-liquids (CTL) and coal-biomass to liquids (CBTL) processes by testing and validating Chevron’s highly selective and active cobalt-zeolite hybrid Fischer-Tropsch (FT) catalyst to convert gasifier syngas predominantly to gasoline, jet fuel and diesel range hydrocarbon liquids, thereby eliminating expensive wax upgrading operations The National Carbon Capture Center (NCCC) operated by Southern Company (SC) at Wilsonville, Alabama served as the host site for the gasifier slip-stream testing/demonstration. Southern Research designed, installed and commissioned a bench scale skid mounted FT reactor system (SR-CBTL test rig) that was fully integrated with a slip stream from SC/NCCC’s transport integrated gasifier (TRIGTM). The test-rig was designed to receive up to 5 lb/h raw syngas augmented with bottled syngas to adjust the H2/CO molar ratio to 2, clean it to cobalt FT catalyst specifications, and produce liquid FT products at the design capacity of 2 to 4 L/day. It employed a 2-inch diameter boiling water jacketed fixed-bed heat-exchange FT reactor incorporating Chevron’s catalyst in Intramicron’s high thermal conductivity micro-fibrous entrapped catalyst (MFEC) packing to efficiently remove heat produced by the highly exothermic FT reaction.

  11. Analysis and control of the METC fluid bed gasifier. Final report (includes technical progress report for October 1994--January 1995), September 1994--September 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-01

    This document presents a modeling and control study of the Fluid Bed Gasification (FBG) unit at the Morgantown Energy Technology Center (METC). The work is performed under contract no. DE-FG21-94MC31384. The purpose of this study is to generate a simple FBG model from process data, and then use the model to suggest an improved control scheme which will improve operation of the gasifier. The work first developes a simple linear model of the gasifier, then suggests an improved gasifier pressure and MGCR control configuration, and finally suggests the use of a multivariable control strategy for the gasifier.

  12. 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

  13. Investigation of Continuous Gas Engine CHP Operation on Biomass Producer Gas

    DEFF Research Database (Denmark)

    Ahrenfeldt, Jesper; Henriksen, Ulrik Birk; Jensen, Torben Kvist;

    2005-01-01

    heat from the exhaust gas is utilised for drying and pyrolysis of the biomass in the gasification system, and the engine directly controls the load of the gasifier. Two different control approaches have been applied and investigated: one where the flow rate of the producer gas is fixed and the engine...... conditions when compared to the current regulation for CO emissions. Measurements of the PAH showed that there were no detectable PAH in exhaust gas from the engine when it is operated on producer gas. The emissions of aldehydes were measured to be significantly lower for producer gas operation than for...

  14. Implementation of the biomass gasification project for community empowerment at Melani village, Eastern Cape, South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Mamphweli, Ntshengedzeni S.; Meyer, Edson L. [University of Fort Hare, Institute of Technology, Private Bag X1314, Alice 5700 (South Africa)

    2009-12-15

    Eskom and the University of Fort Hare are engaged in a biomass gasification project using the System Johansson Biomass gasifier (SJBG). The SJBG installed at Melani village in the Eastern Cape province of South Africa is used to assess the viability and affordability of biomass gasification in South Africa. A community needs assessment study was undertaken at the village before the installation of the plant. The study revealed the need for low-cost electricity for small businesses including growing of crops, chicken broilers, manufacturing of windows and door frames, sewing of clothing, bakery etc. It was also found that the community had a problem with the socio-environmental aspects of burning biomass waste from the sawmill furnace as a means of waste management. The SJBG uses the excess biomass materials (waste) to generate low-cost electricity to drive community economic development initiatives. A study on the properties and suitability of the biomass materials resulting from sawmill operation and their suitability for gasification using the SJBG was undertaken. The study established that the biomass materials meet the requirements for the SJBG. A 300 Nm{sup 3}/h SJBG was then manufactured and installed at the village. (author)

  15. Energy and exergy analyses of an integrated CCHP system with biomass air gasification

    International Nuclear Information System (INIS)

    Highlights: • Propose a biomass-gasification CCHP system. • A heat pipe heat exchanger is used to recover waste heat from product gas. • Present the energy and exergy analyses of the biomass CCHP system. • Analyze the annual off-design performances. - Abstract: Biomass-fueled combined cooling, heating, and power (CCHP) system is a sustainable distributed energy system to reduce fossil energy consumption and carbon dioxide emission. This study proposes a biomass CCHP system that contains a biomass gasifier, a heat pipe heat exchanger for recovering waste heat from product gas, an internal combustion engine to produce electricity, an absorption chiller/heater for cooling and heating, and a heat exchanger to produce domestic hot water. Operational flows are presented in three work conditions: summer, winter, and the transitional seasons. Energy and exergy analyses are conducted for different operational flows. The case demonstrated that the energy efficiencies in the three work conditions are 50.00%, 37.77%, and 36.95%, whereas the exergy efficiencies are 6.23%, 12.51%, and 13.79%, respectively. Destruction analyses of energy and exergy indicate that the largest destruction occurs in the gasification system, which accounts for more than 70% of the total energy and exergy losses. Annual performance shows that the proposed biomass-fueled CCHP system reduces biomass consumption by 4% compared with the non-use of a heat recovery system for high-temperature product gas

  16. Particle size distribution of ashes and the behaviour of metals when firing Salix in a circulating fluidized bed boiler (CFB); Askans partikelfraktionsfoerdelning och metallernas beteende vid eldning av Salix i en CFB-panna

    Energy Technology Data Exchange (ETDEWEB)

    Sfiris, G.; Johansson, A. [Vattenfall Utveckling AB, Stockholm (Sweden); Valmari, T.; Kauppinen, E.; Pyykoenen, J.; Lyyraenen, J. [VTT Technical Research Centre of Finland, Espoo (Finland)

    1999-07-01

    This project is part of the Ash Recovery Programme aimed at establishing the environmental, technical and financial preconditions for returning wood ash to the forest. The programme is funded jointly by NUTEK, Sydkraft and Vattenfall. This report summarises the results of the experimental and modelling work to study the behaviour of the metals (especially Cd and K), after burning Salix in a 3-12 MW Circulating Fluidized Bed (CFB) boiler. The purpose of the study was to determine, using the experimental data, where cadmium and potassium condense, on what size particles they condense, and the decisive parameters governing these processes. Measurements of the fly ash particle size distribution carried out with a Berner Low Pressure Impactor (BLPI), coupled to a pre-cyclone. Samples were collected from three points: in the convection path at 650 deg C, after the convection path but before the secondary cyclone (160 deg C), and after the bag house (150 deg C). Wet chemical sampling was made for Cd, K, Zn and Pb, with three types of sampling equipment: collection of both particles and gas, collection of particles only, and analysis of the gas phase only. Analysis was made of samples from two places in the convection path (650 deg C and 250 deg C). Samples of bed material, bottom ash and fly ash have been subjected to scanning electron microscopy (SEM), and in addition a few fly ash particles, sampled after the convection path, were subjected to energy dispersive X-ray analysis (EDX). Based on experimental results, modelling work was carried out with an equilibrium model and with a general aerosol computer model ABC (Aerosol Behaviour in Combustion)

  17. Emission of hydrocarbons and NO{sub x} at low levels of excess air in CFB; Emissioner av kolvaeten och NO{sub x} vid laaga luftoeverskott i CFB

    Energy Technology Data Exchange (ETDEWEB)

    Schuster, R. [TPS Termiska Processer AB, Nykoeping (Sweden)

    1995-06-01

    Low NO{sub x} operation at low excess air levels heighten the risk of increasing the level of hazardous and polluting emissions from the boiler. These emissions are mainly of two types, greenhouse gases and the mutageneous compounds. The aim of this project has been to show which types of emissions and their correlation you can expect when firing a CFB at low excess air levels. Results: The NO{sub x} emission decreases asymptotically with increased CO-level. High load gives higher NO{sub x} -emissions. There is no significant difference in average NO{sub x} value between wood fuel and RDF-mix. The total hydrocarbon (THC) emission level increases exponentially with increased CO{sub l}evel. There was no significant difference between wood and RDF-mix. Measurements of NO{sub x}, O2, CO (dry gas) and THC were made each second. The measurements of light hydrocarbons (VOC) showed only methane and ethene, both with a good correlation to CO. Below 1000 ppm of CO there is practically no ethene. Above 1000-2000 ppm of CO there is a rapidly increasing emission of ethene. The emission levels at given CO-level are influenced by the furnace temperature. The POM, PNA and Ames test analysis showed good correlation with CO and THC. The results indicate an emission increase at about 200-500 ppm of CO and 10-20 ppm of THC. Dioxin was measured on three occasions with RDF-mix as fuel. The measurements showed an increase of dioxin emission at increased THC-emission. The supply of ammonia, into the flue gas before the cyclones, gave no significant change in hydrocarbon or CO-emission levels. CO, THC and Ames Test are probably good indicators of environmental hazardous compounds. The amount of mutageneous compounds are in general only increased when a certain level of CO is reached. 6 refs, 45 figs, 5 tabs, 7 appendices

  18. Private capital requirements for international biomass energy projects

    International Nuclear Information System (INIS)

    In developing countries, the use of biomass for energy production faces two contradictory pressures. On the one hand, biomass costs very little and it is used inefficiently for fuel or charcoal production, leading to widespread destruction of forested areas and environmental degradation; this problem is being attenuated by the promotion, through aid programmes, of more efficient cook stoves for poor people. On the other hand, the conversion of biomass into high-grade fuel such as ethanol from sugar cane or burning urban refuse or gasifying it to produce electricity is not economically competitive at this time and requires subsidies of approximately 30% to make it as attractive as conventional fuels. Only electricity production using residues from sawmills, crops and other biomass by-products is competitive, and a number of plants are in operation in some countries, particularly the United States. For such plants, the usual rates of return and long-term contract purchases that characterize investments of this kind are applied. Although technologies are available for the widespread efficient use of biomass, the financial hurdle of high initial costs has impeded their market penetration, which in turn precludes any decline in costs that might otherwise have come from production increases. Intervention by governments or by GEF, justified on grounds of environmental protection, is needed to accelerate the introduction of the new technologies. The only private flows that are taking place at the moment are those from enlightened investors wishing to guarantee themselves a strong position in the area for the future or to preempt command and control regulations, such as carbon taxes, imposed by governments. The joint implementation of biomass technologies between industrialized and developing countries might be one method of accelerating this flow. (author)

  19. Demonstration of a 1 MWe biomass power plant at USMC Base Camp Lejeune. Report for July 1994-May 1997

    Energy Technology Data Exchange (ETDEWEB)

    Cleland, J.; Purvis, C.R.

    1998-06-01

    The paper discusses a biomass energy conversion project being sponsored by EPA to demonstrate an enviromentally and economically sound electrical power option for government installations, industrial sites, rural cooperatives, small municipalities, and developing countries. Wood gasification combined with internal combustion engines was chosen because of (1) recent improvements in gas cleaning, (2) simple economical operation for units < 10 MW, and (3) the option of a clean cheap fuel for the many existing facilities generating expensive electricity from petroleum fuels with reciprocating engines. The plant incorporates a downdraft, moving-bed gasifier utilizing hogged waste wood from the Marine Corps Base at Camp Lejeune, NC. A moving-bed bulk wood dryer and both spark ignition and diesel engines are included. Unique process design features are described briefly, relative to the gasifier, wood drying, tar separation, and process control. A test plan for process optimization and demonstration of reliability, economics, and environmental impact is outlined.

  20. Experimental study on biomass gasification in a double air stage downdraft reactor

    International Nuclear Information System (INIS)

    This work presents an experimental study of the gasification of a wood biomass in a moving bed downdraft reactor with two-air supply stages. This configuration is considered as primary method to improve the quality of the producer gas, regarding its tar reduction. By varying the air flow fed to the gasifier and the distribution of gasification air between stages (AR), being the controllable and measurable variables for this type of gasifiers, measuring the CO, CH4 and H2 gas concentrations and through a mass and energy balance, the gas yield and its power, the cold efficiency of the process and the equivalence ratio (ER), as well as other performance variables were calculated. The gasifier produces a combustible gas with a CO, CH4 and H2 concentrations of 19.04, 0.89 and 16.78% v respectively, at a total flow of air of 20 Nm3 h-1 and an AR of 80%. For these conditions, the low heating value of the gas was 4539 kJ Nm-3. Results from the calculation model show a useful gas power and cold efficiency around 40 kW and 68%, respectively. The resulting ER under the referred operation condition is around 0.40. The results suggested a considerable effect of the secondary stage over the reduction of the CH4 concentration which is associated with the decreases of the tar content in the produced gas. Under these conditions the biomass devolatilization in the pyrolysis zone gives much lighter compounds which are more easily cracked when the gas stream passes through the combustion zone. -- Highlights: → Obtained results an important for a better phenomenological understanding of processes occurring in two stage gasification reactors. → The air flow is the fundamental parameter in the operation of downdraft gasifiers. → CH4 reduction is associated with a decreases in the tar content. → An enhancement in the thermal cracking of tar is carried out in the two-air downdraft gasifier.

  1. Pretreated densified biomass products

    Science.gov (United States)

    Dale, Bruce E; Ritchie, Bryan; Marshall, Derek

    2014-03-18

    A product comprising at least one densified biomass particulate of a given mass having no added binder and comprised of a plurality of lignin-coated plant biomass fibers is provided, wherein the at least one densified biomass particulate has an intrinsic density substantially equivalent to a binder-containing densified biomass particulate of the same given mass and h a substantially smooth, non-flakey outer surface. Methods for using and making the product are also described.

  2. Energy use of biomass

    OpenAIRE

    HOLEČKOVÁ, Michaela

    2010-01-01

    The aim of this bachelor thesis is the research of different types of biomass, description of the various types of methods and technologies for energy usage of biomass and the mapping of large power plant units in the Czech Republic. The first part of this thesis deals with the definition of biomass, its distribution and the description of basic essential attributes describing its composition. The downstream part of this work is focused on the technologies of gaining energy out of biomass or ...

  3. Mechanism study on the influence of in situ SOx removal on N2O emission in CFB boiler

    International Nuclear Information System (INIS)

    Highlights: • The presence of SO2 would hinder N2O decomposition on CaO (1 0 0) surface. • N2O decomposition pathway on deSOx intermediate was proposed. • Temperature dependence of the reaction pathway was considered. • Surface recovery process was the rate-determining step for N2O catalytic decomposition. - Abstract: The influence of in situ deSOx process on N2O emission in CFB boiler was studied using density functional theory calculations. The competitive adsorption of SO2 and N2O on pure CaO (1 0 0) surface was first studied and the reaction priority was determined. Results showed that SO2 was more likely to adsorb on CaO (1 0 0) surface O anion site, which hindered the catalytic decomposition of N2O on CaO (1 0 0) surface and sulfurized the CaO (1 0 0) surface under reducing atmosphere. Then a partially sulfurized CaO (1 0 0) surface was established to study the catalytic activity of deSOx reaction intermediate on N2O decomposition. The O atom transfer process and the surface recovery process were two key steps for N2O decomposition and the rate-determining step was the latter one. The sulfurization of the surface could deactivate its catalytic activity on N2O decomposition compared with pure CaO (1 0 0) surface but it was still better than that of pure CaS (1 0 0) surface. The free Gibbs energy was calculated to incorporate the temperature dependence of respective reactions. When temperature was higher than 373 K, the surface recovery was more likely to proceed via the LH route

  4. 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.

  5. Proteins in biomass streams

    NARCIS (Netherlands)

    Mulder, W.J.

    2010-01-01

    The focus of this study is to give an overview of traditional and new biomasses and biomass streams that contain proteins. When information was available, the differences in molecular structure and physical and chemical properties for the different proteins is given. For optimal biomass use, isolati

  6. Development of standardized air-blown coal gasifier/gas turbine concepts for future electric power systems. Volume 2, Appendix A: Fixed bed gasifier and sulfur sorbent regeneration subsystem computer model development: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Blough, E.; Russell, W.; Leach, J.W.

    1990-08-01

    Computer models have been developed for evaluating conceptual designs of integrated coal gasification combined cycle power plants. An overall system model was developed for performing thermodynamic cycle analyses, and detailed models were developed for predicting performance characteristics of fixed bed coal gasifiers and hot gas clean up subsystem components. The overall system model performs mass and energy balances and does chemical equilibrium analyses to determine the effects of changes in operating conditions, or to evaluate proposed design changes. An existing plug flow model for fixed bed gasifiers known as the Wen II model was revised and updated. Also, a spread sheet model of zinc ferrite sulfur sorbent regeneration subsystem was developed. Parametric analyses were performed to determine how performance depends on variables in the system design. The work was done to support CRS Sirrine Incorporated in their study of standardized air blown coal gasifier gas turbine concepts.

  7. Research and development to prepare and characterize robust coal/biomass mixtures for direct co-feeding into gasification systems

    Energy Technology Data Exchange (ETDEWEB)

    Felix, Larry [Inst. Of Gas Technology, Des Plaines, IL (United States); Farthing, William [Inst. Of Gas Technology, Des Plaines, IL (United States); Hoekman, S. Kent [Inst. Of Gas Technology, Des Plaines, IL (United States)

    2014-12-31

    This project was initiated on October 1, 2010 and utilizes equipment and research supported by the Department of Energy, National Energy Technology Laboratory, under Award Number DE- FE0005349. It is also based upon previous work supported by the Department of Energy, National Energy Technology Laboratory, under Award Numbers DOE-DE-FG36-01GOl1082, DE-FG36-02G012011 or DE-EE0000272. The overall goal of the work performed was to demonstrate and assess the economic viability of fast hydrothermal carbonization (HTC) for transforming lignocellulosic biomass into a densified, friable fuel to gasify like coal that can be easily blended with ground coal and coal fines and then be formed into robust, weather-resistant pellets and briquettes. The specific objectives of the project include: • Demonstration of the continuous production of a uniform densified and formed feedstock from loblolly pine (a lignocellulosic, short rotation woody crop) in a hydrothermal carbonization (HTC) process development unit (PDU). • Demonstration that finely divided bituminous coal and HTC loblolly pine can be blended to form 90/10 and 70/30 weight-percent mixtures of coal and HTC biomass for further processing by pelletization and briquetting equipment to form robust weather resistant pellets and/or briquettes suitable for transportation and long term storage. • Characterization of the coal-biomass pellets and briquettes to quantify their physical properties (e.g. flow properties, homogeneity, moisture content, particle size and shape), bulk physical properties (e.g. compressibility, heat transfer and friability) and assess their suitability for use as fuels for commercially-available coal gasifiers. • Perform economic analyses using Aspen-based process simulations to determine the costs for deploying and operating HTC processing facilities for the production of robust coal/biomass fuels suitable for fueling commercially-available coal-fired gasifiers. This Final Project Scientific

  8. Dynamic characteristics of Oxy-CFB combustion system based on Aspen%基于Aspen平台的Oxy-CFB燃烧侧动态特性模拟

    Institute of Scientific and Technical Information of China (English)

    周建新; 邵壮; 李崇; 司风琪; 徐治皋

    2014-01-01

    Taking an oxy-fuel circulating fluidized bed (Oxy-CFB )combustor pilot facility as the simulation object,a steady-state model for the Oxy-CFB combustion system was built with the plat-form of Aspen Plus.After modifying the steady-state model for the dynamic process simulation,a new dynamic model for the combustion system was built based on Aspen Dynamics and the results were validated by the test data.The simulation study on the responses of the bed temperature and the components,including carbon dioxide,oxygen,carbon monoxide,and nitrogen monoxide in the flue gas,was carried out.The research results show that the dynamic model based on Aspen pro-vides a new method to investigate the dynamic characteristics of the Oxy-CFB combustion system. The dynamic response characteristics of bed temperature and gas components for the coal feed and primary air step changes can provide valuable information for design and implementation of the con-trol system of the Oxy-CFB combustion system.%以某循环流化床富氧燃烧中试系统为模拟对象,借助Aspen Plus流程模拟软件搭建了Oxy-CFB燃烧系统的稳态模型。在此基础上针对动态过程模拟进行改进,并利用Aspen Dynam-ics平台建立了该燃烧系统的动态模型,利用试验数据对模拟结果进行了验证。基于动态模型对Oxy-CFB床温以及燃烧排放产物中二氧化碳、氧气、一氧化碳、一氧化氮等进行了仿真研究。研究表明,基于Aspen平台的动态过程模拟为Oxy-CFB锅炉燃烧系统的动态特性分析提供了新的研究手段,模拟所得的床温及烟气各组分随给煤量、一次风量阶跃变化的动态响应规律可为今后Oxy-CFB燃烧系统的控制设计提供重要依据。

  9. Mathematical modelling of the gasification of cellulose-containing biomass using a zoning model; Mathematische Modellierung der Vergasung zellulosehaltiger Biomasse mit Hilfe eines Zonenmodells

    Energy Technology Data Exchange (ETDEWEB)

    Jung, K.; Saller, G.; Funk, G.; Krumm, W. [Siegen Univ. (Gesamthochschule) (Germany). Inst. fuer Energietechnik

    1998-09-01

    The composition of the product gas is decisive for the further process stages. In contrast to coal gasification, which has been investigated for more than a century, there is still a lack of theoretical and experimental knowledge on biomass gasification. The contribution presents a mathematical model that is to provide deeper knowledge of the constant-flow fixed-bed gasifier, which is still widely regarded as a `black box`. (orig./SR) [Deutsch] Einen wesentlichen Prozessschritt der thermochemischen Konversion stellt der Vergasungsprozess dar, da die Zusammensetzung des erhaltenen Gases fuer die weiteren Prozessschritte von entscheidender Bedeutung ist. Im Gegensatz zur Vergasung von Kohle, die bereits seit fast 100 Jahren untersucht wird, besteht bei der Vergasung von Biomasse ein starker Nachholbedarf in Bezug auf das theoretische und experimentelle Detailwissen. In diesem Beitrag wird im Rahmen eines mathematischen Modells ein Ansatz vorgestellt, in dem der Gleichstrom-Festbettvergaser, der bisher meist als `blackbox` betrachtet wurde, weiter aufgeschluesselt wird. (orig./SR)

  10. The investigations of temperature distributions in an opposed multi-burner gasifier

    International Nuclear Information System (INIS)

    Research highlights: → The temperatures of gasification chamber and quench chamber are measured by thermocouples. → The temperatures of gasification chamber increase slowly as the inserted distance increases in both diesel and coal -water slurry (CWS) tests. → The syngas temperature decrease rapidly when it passes through the inlet of quench chamber. → Flame temperature distributions are reconstructed by the Filtered back-projection method. → Temperature distributions of diesel impinging flames are 1650-2100 oC and those of CWS flames are 1500-2000 oC at the test conditions. -- Abstract: In a bench-scale opposed multi-burner (OMB) gasifier, the temperatures of gasification chamber and quench chamber are measured by thermocouples, and the temperature distributions of flame sections are reconstructed by the Filtered back-projection method. The results show that the temperature of gasification chamber increases slowly as the inserted distance increases in both diesel and coal-water slurry (CWS) tests. The syngas temperature decreases rapidly when it passes through the inlet of quench chamber. The impinging flames of diesel or CWS gasification all focus on the gasifier center due to restraining by each other, and can avoid scouring the refractory wall and prolong the lives of refractory. At the test conditions, the temperature distributions of diesel flames are 1650-2100 oC and those of CWS flames are 1500-2000 oC. The flame temperature distributions appear to be a typical simple peak. The investigations can provide some information for the industrial gasifier.

  11. A simulation study on the enhancement of the shift reaction by water injection into a gasifier

    International Nuclear Information System (INIS)

    Although coal gasification is a clean and efficient use of coal, a reduction of CO2 emissions is needed to mitigate global warming. The aim of this study was to improve the thermal efficiency of fuel production and electricity generation by dry coal feed gasification. The primary cause of thermal efficiency loss is steam use in a water-gas shift reactor. The shift reactor, installed downstream from the gasifier, uses a catalyst to adjust the H2/CO ratio of the syngas. We have proposed a new process in which water is injected at the outlet of the gasifier and is vaporized to enhance the extent of the shift reaction. This process utilizes the high temperature of the syngas, which is sufficient for the shift reaction to occur without a catalyst. We have developed a model that incorporates the shift reaction velocity to evaluate our proposed process. In an optimized 5-stage water supply case, we found that the CO conversion reaches 9.9% at a water/syngas ratio of 0.14 mol/mol (water/CO = 0.25 mol/mol); the CO conversion needed for dimethyl ether production is 31%. This new process can improve the efficiency and reduce the cost of coal gasification. -- Highlights: → The process enhancing the shift reaction by water injection into a Gasifier was proposed. → Five-stage water supply to prevent a rapid temperature drop is optimal. → CO conversion reaches 9.9% at a water/syngas ratio of 0.14 mol/mol (water/CO = 0.25 mol/mol). → Amount of steam required for the shift reactor in fuel production process can be reduced.

  12. Distributed Fiber Optic Sensor for On-Line Monitoring of Coal Gasifier Refractory Health

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Anbo [Center for Photonics Technology, Blacksburgh, VA (United States); Yu, Zhihao [Center for Photonics Technology, Blacksburgh, VA (United States)

    2015-11-30

    This report summarizes technical progress on the program “Distributed Fiber Optic Sensor for On-Line Monitoring of Coal Gasifier Refractory Health,” funded by the National Energy Technology Laboratory of the U.S. Department of Energy, and performed by the Center for Photonics Technology of the Bradley Department of Electrical and Computer Engineering at Virginia Tech. The scope of work entails analyses of traveling grating generation technologies in an optical fiber, as well as the interrogation of the gratings to infer a distributed temperature along the fiber, for the purpose of developing a real-time refractory health condition monitoring technology for coal gasifiers. During the project period, which is from 2011-2015, three different sensing principles were studied, including four-wave mixing (FWM), coherent optical time-domain reflectometer (C-OTDR) and Brillouin optical time-domain analysis (BOTDA). By comparing the three methods, the BOTDA was selected for further development into a complete bench-top sensing system for the proposed high-temperature sensing application. Based on the input from Eastman Chemical, the industrial collaborator on this project, a cylindrical furnace was designed and constructed to simulate typical gasifier refractory temperature conditions in the laboratory, and verify the sensor’s capability to fully monitor refractory conditions on the back-side at temperatures up to 1000°C. In the later stages of the project, the sensing system was tested in the simulated environment for its sensing performance and high-temperature survivability. Through theoretical analyses and experimental research on the different factors affecting the sensor performance, a sensor field deployment strategy was proposed for possible future sensor field implementations.

  13. Development of small, modular biomass power systems

    Energy Technology Data Exchange (ETDEWEB)

    Turnbull, J.H. [Peninsula Energy Partners, Los Altos, CA (United States); Hulkkonen, S. [IVO/EPRI, Palo Alto, CA (United States); Dracker, R. [Bechtel Corp., San Francisco, CA (United States)

    1996-12-31

    This paper describes a collaborative effort between the Electric Power Research Institute, Bechtel Corporation and Imatran Voima Oy. The goal is commercialization of a biomass-fueled, modular (50 to 250 kW) heat and power technology for distributed applications. The technology to be selected will not present any major technical challenges, but first and foremost must be simple and reliable. Additional criteria include: acceptable capital cost, fuel flexibility, and the capability for meeting local environmental standards. As the capital cost of small units will be influenced by economies of fabrication, the economic viability of these systems depends upon the size of the domestic and international markets. Thus, evaluation of available conversion technologies was undertaken concurrently with a broad-based market assessment. The technology scan included all the commercial and pre-commercial biomass systems that could be located. Information was sorted into five categories: (1) gasifiers with either diesel or spark-ignited engines; (2) indirectly fired gas turbines; (3) directly fired gas turbines; (4) pyrolysis processes with diesel engines; or (5) conventional steam-cycles. The evaluation of the technologies was based on the above criteria, along with the recognition that the levelized cost of power from the system must be competitive with available diesel generation. The market for these systems within the contiguous 48 states is expected to be limited to situations involving forest ecosystem improvements and the reduction of forest fire hazards, and/or clean-up and remediation following natural disasters. Another North American market is remote villages in Canada and Alaska. By far the largest market is in developing nations where two billion people are without electricity for lighting, water pumping or refrigeration. Serving this latter market presents a major challenge, as each system will require establishment of a whole new local infrastructure.

  14. Gasification of municipal solid waste in a downdraft gasifier: Analysis of tar formation

    OpenAIRE

    Tabitha Geoffrey Etutu; Krongkaew Laohalidanond; Somrat Kerdsuwan

    2016-01-01

    In this study, municipal solid waste (MSW) from a dumpsite was converted into refuse derived fuel (RDF) and used as feedstock for an air-blown gasification process. The gasification process was conducted in a 10 kg.hr -1 downdraft gasifier at different air flow rates of 300, 350, 400, 450 and 550 NL.min1 at atmospheric pressure in order to investigate the quantity and quality of tar formed. It was shown that the increase in the air flow rate from 300 NL.min1 to 550 NL.mi...

  15. Fixed-bed gasifier and cleanup system engineering summary report through Test Run No. 100

    Energy Technology Data Exchange (ETDEWEB)

    Pater, K. Jr.; Headley, L.; Kovach, J.; Stopek, D.

    1984-06-01

    The state-of-the-art of high-pressure, fixed-bed gasification has been advanced by the many refinements developed over the last 5 years. A novel full-flow gas cleanup system has been installed and tested to clean coal-derived gases. This report summarizes the results of tests conducted on the gasifier and cleanup system from its inception through 1982. Selected process summary data are presented along with results from complementary programs in the areas of environmental research, process simulation, analytical methods development, and component testing. 20 references, 32 figures, 42 tables.

  16. Thermodynamic optimization of biomass gasification for decentralized power generation and Fischer-Tropsch synthesis

    International Nuclear Information System (INIS)

    In recent years, biomass gasification has emerged as a viable option for decentralized power generation, especially in developing countries. Another potential use of producer gas from biomass gasification is in terms of feedstock for Fischer-Tropsch (FT) synthesis - a process for manufacture of synthetic gasoline and diesel. This paper reports optimization of biomass gasification process for these two applications. Using the non-stoichometric equilibrium model (SOLGASMIX), we have assessed the outcome of gasification process for different combinations of operating conditions. Four key parameters have been used for optimization, viz. biomass type (saw dust, rice husk, bamboo dust), air or equivalence ratio (AR = 0, 0.2, 0.4, 0.6, 0.8 and 1), temperature of gasification (T = 400, 500, 600, 700, 800, 900 and 1000 oC), and gasification medium (air, air-steam 10% mole/mole mixture, air-steam 30%mole/mole mixture). Performance of the gasification process has been assessed with four measures, viz. molar content of H2 and CO in the producer gas, H2/CO molar ratio, LHV of producer gas and overall efficiency of gasifier. The optimum sets of operating conditions for gasifier for FT synthesis are: AR = 0.2-0.4, Temp = 800-1000 oC, and gasification medium as air. The optimum sets of operating conditions for decentralized power generation are: AR = 0.3-0.4, Temp = 700-800 oC with gasification medium being air. The thermodynamic model and methodology presented in this work also presents a general framework, which could be extended for optimization of biomass gasification for any other application.

  17. Investigation of flow behaviour of coat/ash particles in an advanced pressurised fluidized bed gasifier (APFBG) using radiotracer technique

    International Nuclear Information System (INIS)

    Knowledge of Residence Time Distribution (RTD), Mean Residence Time (MRT) and degree of backmixing of solid phase is important for efficient operation of the coal gasifier. Radiotracer technique was used for measure RTD of coal/ash particles in a pilot-scale gasifier and obtain the values of MRT and backmixing. Lanthanum 140 labeled coal (100 g) was used as a tracer. The tracer was instantaneously injected into the coal feed line and monitored at ash and gas outlets of the gasifier using collimated scintillation detectors. The measured RTD data were treated and MRTs of coal/ash particles were determined. The treated data were simulated using tank-in-series model. The simulation RTD data indicated good degree of mixing with minor bypassing/short-circulating of coal particles. The results of the investigation were found useful for scale-up of the gasification process. (author)

  18. Development of standardized air-blown coal gasifier/gas turbine concepts for future electric power systems

    Energy Technology Data Exchange (ETDEWEB)

    Blough, E.; Russell, W.; Leach, J.W.

    1990-08-01

    Computer models have been developed for evaluating conceptual designs of integrated coal gasification combined cycle power plants. An overall system model was developed for performing thermodynamic cycle analyses, and detailed models were developed for predicting performance characteristics of fixed bed coal gasifiers and hot gas clean up subsystem components. The overall system model performs mass and energy balances and does chemical equilibrium analyses to determine the effects of changes in operating conditions, or to evaluate proposed design changes. An existing plug flow model for fixed bed gasifiers known as the Wen II model was revised and updated. Also, a spread sheet model of zinc ferrite sulfur sorbent regeneration subsystem was developed. Parametric analyses were performed to determine how performance depends on variables in the system design. The work was done to support CRS Sirrine Incorporated in their study of standardized air blown coal gasifier gas turbine concepts.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-12-31

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

  20. Techno-economic assessment of FT unit for synthetic diesel production in existing stand-alone biomass gasification plant using process simulation tool

    DEFF Research Database (Denmark)

    Hunpinyo, Piyapong; Narataruksa, Phavanee; Tungkamani, Sabaithip;

    2014-01-01

    For alternative thermo-chemical conversion process route via gasification, biomass can be gasified to produce syngas (mainly CO and H2). On more applications of utilization, syngas can be used to synthesize fuels through the catalytic process option for producing synthetic liquid fuels such as...... are currently no plans to engage the FT process in Thailand, the authors have targeted that this work focus on improving the FT configurations in existing biomass gasification facilities (10 MWth). A process simulation model for calculating extended unit operations in a demonstrative context is...

  1. Life cycle assessment of a biomass gasification combined-cycle power system

    Energy Technology Data Exchange (ETDEWEB)

    Mann, M.K.; Spath, P.L.

    1997-12-01

    The potential environmental benefits from biomass power are numerous. However, biomass power may also have some negative effects on the environment. Although the environmental benefits and drawbacks of biomass power have been debated for some time, the total significance has not been assessed. This study serves to answer some of the questions most often raised in regard to biomass power: What are the net CO{sub 2} emissions? What is the energy balance of the integrated system? Which substances are emitted at the highest rates? What parts of the system are responsible for these emissions? To provide answers to these questions, a life cycle assessment (LCA) of a hypothetical biomass power plant located in the Midwest United States was performed. LCA is an analytical tool for quantifying the emissions, resource consumption, and energy use, collectively known as environmental stressors, that are associated with converting a raw material to a final product. Performed in conjunction with a technoeconomic feasibility study, the total economic and environmental benefits and drawbacks of a process can be quantified. This study complements a technoeconomic analysis of the same process, reported in Craig and Mann (1996) and updated here. The process studied is based on the concept of power Generation in a biomass integrated gasification combined cycle (BIGCC) plant. Broadly speaking, the overall system consists of biomass production, its transportation to the power plant, electricity generation, and any upstream processes required for system operation. The biomass is assumed to be supplied to the plant as wood chips from a biomass plantation, which would produce energy crops in a manner similar to the way food and fiber crops are produced today. Transportation of the biomass and other materials is by both rail and truck. The IGCC plant is sized at 113 MW, and integrates an indirectly-heated gasifier with an industrial gas turbine and steam cycle. 63 refs., 34 figs., 32 tabs.

  2. Thermodynamic analysis and comparison of downdraft gasifiers integrated with gas turbine, spark and compression ignition engines for distributed power generation

    International Nuclear Information System (INIS)

    The objective of the present article is to assess and compare the performance of electricity generation systems integrated with downdraft biomass gasifiers for distributed power generation. A model for estimating the electric power generation of internal combustion engines and gas turbines powered by syngas was developed. First, the model determines the syngas composition and the lower heating value; and second, these data are used to evaluate power generation in Otto, Diesel, and Brayton cycles. Four synthesis gas compositions were tested for gasification with: air; pure oxygen; 60% oxygen with 40% steam; and 60% air with 40% steam. The results show a maximum power ratio of 0.567 kWh/Nm3 for the gas turbine system, 0.647 kWh/Nm3 for the compression ignition engine, and 0.775 kWh/Nm3 for the spark-ignition engine while running on synthesis gas which was produced using pure oxygen as gasification agent. When these three systems run on synthesis gas produced using atmospheric air as gasification agent, the maximum power ratios were 0.274 kWh/Nm3 for the gas turbine system, 0.302 kWh/Nm3 for CIE, and 0.282 kWh/Nm3 for SIE. The relationship between power output and synthesis gas flow variations is presented as is the dependence of efficiency on compression ratios. Since the maximum attainable power ratio of CIE is higher than that of SIE for gasification with air, more research should be performed on utilization of synthesis gas in CIE. - Highlights: •Engines and gas turbines integrated with gasification were compared. •Four different gasification agents were considered in the analysis. •It was found that a syngas–air mixture has to be considered in the compression. •Good accuracy with respect to available experimental data. •For air gasification higher power ratio was found for compression ignition engines

  3. Numerical simulations for the coal/oxidant distribution effects between two-stages for multi opposite burners (MOB) gasifier

    International Nuclear Information System (INIS)

    Highlights: • We simulated a double stage 3D entrained flow coal gasifier with multi-opposite burners. • The various reaction mechanisms have evaluated with experimental results. • The effects of coal and oxygen distribution between two stages on the performance of gasifier have investigated. • The local coal to oxygen ratio is affecting the overall efficiency of gasifier. - Abstract: A 3D CFD model for two-stage entrained flow dry feed coal gasifier with multi opposite burners (MOB) has been developed in this paper. At each stage two opposite nozzles are impinging whereas the two other opposite nozzles are slightly tangential. Various numerical simulations were carried out in standard CFD software to investigate the impacts of coal and oxidant distributions between the two stages of the gasifier. Chemical process was described by Finite Rate/Eddy Dissipation model. Heterogeneous and homogeneous reactions were defined using the published kinetic data and realizable k–ε turbulent model was used to solve the turbulence equations. Gas–solid interaction was defined by Euler–Lagrangian frame work. Different reaction mechanism were investigated first for the validation of the model from published experimental results. Then further investigations were made through the validated model for important parameters like species concentrations in syngas, char conversion, maximum inside temperature and syngas exit temperature. The analysis of the results from various simulated cases shows that coal/oxidant distribution between the stages has great influence on the overall performance of gasifier. The maximum char conversion was found 99.79% with coal 60% and oxygen 50% of upper level of injection. The minimum char conversion was observed 95.45% at 30% coal with 40% oxygen at same level. In general with oxygen and coal above or equal to 50% of total at upper injection level has shown an optimized performance

  4. INTEGRATED PYROLYSIS COMBINED CYCLE BIOMASS POWER SYSTEM CONCEPT DEFINITION

    Energy Technology Data Exchange (ETDEWEB)

    Eric Sandvig; Gary Walling; Robert C. Brown; Ryan Pletka; Desmond Radlein; Warren Johnson

    2003-03-01

    Advanced power systems based on integrated gasification/combined cycles (IGCC) are often presented as a solution to the present shortcomings of biomass as fuel. Although IGCC has been technically demonstrated at full scale, it has not been adopted for commercial power generation. Part of the reason for this situation is the continuing low price for coal. However, another significant barrier to IGCC is the high level of integration of this technology: the gas output from the gasifier must be perfectly matched to the energy demand of the gas turbine cycle. We are developing an alternative to IGCC for biomass power: the integrated (fast) pyrolysis/ combined cycle (IPCC). In this system solid biomass is converted into liquid rather than gaseous fuel. This liquid fuel, called bio-oil, is a mixture of oxygenated organic compounds and water that serves as fuel for a gas turbine topping cycle. Waste heat from the gas turbine provides thermal energy to the steam turbine bottoming cycle. Advantages of the biomass-fueled IPCC system include: combined cycle efficiency exceeding 37 percent efficiency for a system as small as 7.6 MW{sub e}; absence of high pressure thermal reactors; decoupling of fuel processing and power generation; and opportunities for recovering value-added products from the bio-oil. This report provides a technical overview of the system including pyrolyzer design, fuel clean-up strategies, pyrolysate condenser design, opportunities for recovering pyrolysis byproducts, gas turbine cycle design, and Rankine steam cycle. The report also reviews the potential biomass fuel supply in Iowa, provide and economic analysis, and present a summery of benefits from the proposed system.

  5. INTEGRATED PYROLYSIS COMBINED CYCLE BIOMASS POWER SYSTEM CONCEPT DEFINITION

    International Nuclear Information System (INIS)

    Advanced power systems based on integrated gasification/combined cycles (IGCC) are often presented as a solution to the present shortcomings of biomass as fuel. Although IGCC has been technically demonstrated at full scale, it has not been adopted for commercial power generation. Part of the reason for this situation is the continuing low price for coal. However, another significant barrier to IGCC is the high level of integration of this technology: the gas output from the gasifier must be perfectly matched to the energy demand of the gas turbine cycle. We are developing an alternative to IGCC for biomass power: the integrated (fast) pyrolysis/ combined cycle (IPCC). In this system solid biomass is converted into liquid rather than gaseous fuel. This liquid fuel, called bio-oil, is a mixture of oxygenated organic compounds and water that serves as fuel for a gas turbine topping cycle. Waste heat from the gas turbine provides thermal energy to the steam turbine bottoming cycle. Advantages of the biomass-fueled IPCC system include: combined cycle efficiency exceeding 37 percent efficiency for a system as small as 7.6 MWe; absence of high pressure thermal reactors; decoupling of fuel processing and power generation; and opportunities for recovering value-added products from the bio-oil. This report provides a technical overview of the system including pyrolyzer design, fuel clean-up strategies, pyrolysate condenser design, opportunities for recovering pyrolysis byproducts, gas turbine cycle design, and Rankine steam cycle. The report also reviews the potential biomass fuel supply in Iowa, provide and economic analysis, and present a summery of benefits from the proposed system

  6. Identification of reaction zones in a commercial Sasol-Lurgi fixed bed dry bottom gasifier operating on North Dakota lignite

    OpenAIRE

    Baker, G; Bunt, John Reginald; Waanders, Frans Boudewijn; Mangena, S.J.

    2011-01-01

    The Sasol-Lurgi fixed bed dry bottom gasification technology has the biggest market share in the world with 101 gasifiers in operation. To be able to further improve the technology and also to optimise the operating plants, it is important that the fundamentals of the process are understood. The main objective of this study was to determine the reaction zones occurring in the Sasol-Lurgi fixed bed dry bottom (S-L FBDB) gasifier operating on North Dakota lignite. A Turn-Out sampling method and...

  7. Effect of Coal Properties and Operation Conditions on Flow Behavior of Coal Slag in Entrained Flow Gasifiers: A Brief Review

    Energy Technology Data Exchange (ETDEWEB)

    Wang,Ping; Massoudi, Mehrdad

    2011-01-01

    Integrated gasification combined cycle (IGCC) is a potentially promising clean technology with an inherent advantage of low emissions, since the process removes contaminants before combustion instead of from flue gas after combustion, as in a conventional coal steam plant. In addition, IGCC has potential for cost-effective carbon dioxide capture. Availability and high capital costs are the main challenges to making IGCC technology more competitive and fully commercial. Experiences from demonstrated IGCC plants show that, in the gasification system, low availability is largely due to slag buildup in the gasifier and fouling in the syngas cooler downstream of the gasification system. In the entrained flow gasifiers used in IGCC plants, the majority of mineral matter transforms to liquid slag on the wall of the gasifier and flows out the bottom. However, a small fraction of the mineral matter (as fly ash) is entrained with the raw syngas out of the gasifier to downstream processing. This molten/sticky fly ash could cause fouling of the syngas cooler. Therefore, it is preferable to minimize the quantity of fly ash and maximize slag. In addition, the hot raw syngas is cooled to convert any entrained molten fly slag to hardened solid fly ash prior to entering the syngas cooler. To improve gasification availability through better design and operation of the gasification process, better understanding of slag behavior and characteristics of the slagging process are needed. Slagging behavior is affected by char/ash properties, gas compositions in the gasifier, the gasifier wall structure, fluid dynamics, and plant operating conditions (mainly temperature and oxygen/carbon ratio). The viscosity of the slag is used to characterize the behavior of the slag flow and is the dominating factor to determine the probability that ash particles will stick. Slag viscosity strongly depends on the temperature and chemical composition of the slag. Because coal has varying ash content and

  8. CFD Modelling Applied to the Co-Combustion of Paper Sludge and Coal in a 130 t/h CFB Boiler

    Science.gov (United States)

    Yu, Z. S.; Ma, X. Q.; Lai, Z. Y.; Xiao, H. M.

    Three-dimensional mathematical model has been developed as a tool for co-combustion of paper sludge and coal in a 130 tJh Circulating Fluidized Bed (CFB) boiler. Mathematical methods had been used based on a commercial software FLUENT for combustion. The predicted results of CFB furnace show that the co-combustion of paper sludge/coal is initially intensively at the bottom of bed; the temperature reaches its maximum in the dense-phase zone, around l400K. It indicates that paper sludge spout into furnace from the recycle inlet can increase the furnace maximum temperature (l396.3K), area-weighted average temperature (l109.6K) and the furnace gas outlet area-weighted average temperature(996.8K).The mathematical modeling also predicts that 15 mass% paper sludge co-combustion is the highest temperature at the flue gas outlet, it is 1000.8K. Moreover, it is proved that mathematical models can serve as a tool for detailed analysis of co-combustion of paper sludge and coal processes in a circulating fluidized bed furnace when in view of its convenience. The results gained from numerical simulation show that paper sludge enter into furnace from the recycle inlet excelled than mixing with coal and at the underside of phase interface.

  9. Influence of operating conditions on the air gasification of dry refinery sludge in updraft gasifier

    Science.gov (United States)

    Ahmed, R.; Sinnathambi, C. M.

    2013-06-01

    In the present work, details of the equilibrium modeling of dry refinery sludge (DRS) are presented using ASPEN PLUS Simulator in updraft gasifier. Due to lack of available information in the open journal on refinery sludge gasification using updraft gasifier, an evaluate for its optimum conditions on gasification is presented in this paper. For this purpose a Taguchi Orthogonal array design, statistical software is applied to find optimum conditions for DRS gasification. The goal is to identify the most significant process variable in DRS gasification conditions. The process variables include; oxidation zone temperature, equivalent ratio, operating pressure will be simulated and examined. Attention was focused on the effect of optimum operating conditions on the gas composition of H2 and CO (desirable) and CO2 (undesirable) in terms of mass fraction. From our results and finding it can be concluded that the syngas (H2 & CO) yield in term of mass fraction favors high oxidation zone temperature and at atmospheric pressure while CO2 acid gas favor at a high level of equivalent ratio as well as air flow rate favoring towards complete combustion.

  10. 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%

  11. Correlation between the critical viscosity and ash fusion temperatures of coal gasifier ashes

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, Peter Y. [National Energy Technology Lab. (NETL), Albany, OR (United States); Kwong, Kyei-Sing [National Energy Technology Lab. (NETL), Albany, OR (United States); Bennett, James [National Energy Technology Lab. (NETL), Albany, OR (United States)

    2015-09-27

    Coal gasification yields synthesis gas, an important intermediate in chemical manufacturing. It is also vital to the production of liquid fuels through the Fischer-Tropsch process and electricity in Integrated Gasification Combined Cycle power generation. Minerals naturally present in coal become molten in entrained-flow slagging gasifiers. Molten coal ash slag penetrates and dissolves refractory bricks, leading to costly plant shutdowns. The extent of coal ash slag penetration and refractory brick dissolution depends on the slag viscosity, the gasification temperature, and the composition of slag and bricks. Here, we measured the viscosity of several synthetic coal ash slags with a high-temperature rotary viscometer and their ash fusion temperatures through optical image analysis. We made all measurements in a carbon monoxide-carbon dioxide reducing atmosphere that approximates coal gasification conditions. Empirical correlation models based on ash fusion temperatures were used to calculate critical viscosity temperatures based on the coal ash compositions. These values were then compared with those obtained from thermodynamic phase-transition models. Finally, an understanding of slag viscosity as a function of ash composition is important to reducing refractory wear in slagging coal gasifiers, which would help to reduce the cost and environmental impact of coal for chemical and electricity production.

  12. Thermodynamic equilibrium model and second law analysis of a downdraft waste gasifier

    International Nuclear Information System (INIS)

    The management of municipal solid waste (MSW) and the current status of world energy resources crisis are important problems. Gasification is a kind of waste-to- energy conversion scheme that offers the most attractive solution to both waste disposal and energy problems. In this study, the thermodynamic equilibrium model based on equilibrium constant for predicting the composition of producer gas in a downdraft waste gasifier was developed. To enhance the performance of the model, further modification was made by multiplying the equilibrium constants with coefficients. The modified model was validated with the data reported by different researchers. MSW in Thailand was then used to simulate and to study the effects of moisture content (MC) of the waste on the gasifier's performance. The results showed that the mole fraction of H2 gradually increases; CO decreases; CH4, which has a very low percentage in the producer gas increases; N2 slightly decreases; and CO2 increases with increasing MC. The reaction temperature, the calorific value, and the second law efficiency, decrease when MC increases

  13. Simulation of emission performance and combustion efficiency in biomass fired circulating fluidized bed combustors

    Energy Technology Data Exchange (ETDEWEB)

    Gungor, Afsin [Nigde University, Faculty of Engineering and Architecture, Department of Mechanical Engineering, 51100 Nigde (Turkey)

    2010-04-15

    In this study, the combustion efficiency and the emission performance of biomass fired CFBs are tested via a previously published 2D model [Gungor A. Two-dimensional biomass combustion modeling of CFB. Fuel 2008; 87: 1453-1468.] against two published comprehensive data sets. The model efficiently simulates the outcome with respect to the excess air values, which is the main parameter that is verified. The combustion efficiency of OC changes between 82.25 and 98.66% as the excess air increases from 10 to 116% with the maximum error of about 8.59%. The rice husk combustion efficiency changes between 98.05 and 97.56% as the bed operational velocity increases from 1.2 to 1.5 m s{sup -1} with the maximum error of about 7.60%. CO and NO{sub x} emissions increase with increasing bed operational velocity. Increasing excess air results in slightly higher levels of NO{sub x} emission. A significant amount of combustion occurs in the upper zone due to the high volatile content of the biomass fuels. (author)

  14. Complex pendulum biomass sensor

    Science.gov (United States)

    Hoskinson, Reed L.; Kenney, Kevin L.; Perrenoud, Ben C.

    2007-12-25

    A complex pendulum system biomass sensor having a plurality of pendulums. The plurality of pendulums allow the system to detect a biomass height and density. Each pendulum has an angular deflection sensor and a deflector at a unique height. The pendulums are passed through the biomass and readings from the angular deflection sensors are fed into a control system. The control system determines whether adjustment of machine settings is appropriate and either displays an output to the operator, or adjusts automatically adjusts the machine settings, such as the speed, at which the pendulums are passed through the biomass. In an alternate embodiment, an entanglement sensor is also passed through the biomass to determine the amount of biomass entanglement. This measure of entanglement is also fed into the control system.

  15. Hydrothermal liquefaction of biomass

    DEFF Research Database (Denmark)

    Toor, Saqib; Rosendahl, Lasse; Hoffmann, Jessica;

    2014-01-01

    can recombine into larger ones. During this process, a substantial part of the oxygen in the biomass is removed by dehy-dration or decarboxylation. The chemical properties of the product are mostly de-pendent of the biomass substrate composition. Biomass consists of various com-ponents such as......Biomass is one of the most abundant sources of renewable energy, and will be an important part of a more sustainable future energy system. In addition to direct combustion, there is growing attention on conversion of biomass into liquid en-ergy carriers. These conversion methods are divided into...... biochemical/biotechnical methods and thermochemical methods; such as direct combustion, pyrolysis, gasification, liquefaction etc. This chapter will focus on hydrothermal liquefaction, where high pressures and intermediate temperatures together with the presence of water are used to convert biomass into...

  16. Experiments on torrefied wood pellet: study by gasification and characterization for waste biomass to energy applications.

    Science.gov (United States)

    Rollinson, Andrew N; Williams, Orla

    2016-05-01

    Samples of torrefied wood pellet produced by low-temperature microwave pyrolysis were tested through a series of experiments relevant to present and near future waste to energy conversion technologies. Operational performance was assessed using a modern small-scale downdraft gasifier. Owing to the pellet's shape and surface hardness, excellent flow characteristics were observed. The torrefied pellet had a high energy density, and although a beneficial property, this highlighted the present inflexibility of downdraft gasifiers in respect of feedstock tolerance due to the inability to contain very high temperatures inside the reactor during operation. Analyses indicated that the torrefaction process had not significantly altered inherent kinetic properties to a great extent; however, both activation energy and pre-exponential factor were slightly higher than virgin biomass from which the pellet was derived. Thermogravimetric analysis-derived reaction kinetics (CO2 gasification), bomb calorimetry, proximate and ultimate analyses, and the Bond Work Index grindability test provided a more comprehensive characterization of the torrefied pellet's suitability as a fuel for gasification and also other combustion applications. It exhibited significant improvements in grindability energy demand and particle size control compared to other non-treated and thermally treated biomass pellets, along with a high calorific value, and excellent resistance to water. PMID:27293776

  17. Demonstration of a 1 MWe biomass power plant at USMC Base Camp Lejeune

    International Nuclear Information System (INIS)

    A biomass energy conversion project is being sponsored by the U.S. Environmental Protection Agency (EPA) to demonstrate an environmentally and economically sound electrical power option for government installations, industrial sites, rural cooperatives, small municipalities, and developing countries. Under a cooperative agreement with EPA, Research Triangle Institute is initiating operation of the Camp Lejeune Energy from Wood (CLEW) biomass plant. Wood gasification combined with internal combustion engines was chosen because of (1) recent improvements in gas cleaning, (2) simple, economical operation for units less than 10 MW, and (3) the option of a clean, cheap fuel for the many existing facilities generating expensive electricity from petroleum fuels with reciprocating engines. The plant incorporates a downdraft, moving bed gasifier utilizing hogged waste wood from the Marine Corps Base at Camp Lejeune, NC. A moving bed bulk wood dryer and both spark ignition and diesel engines are included. Unique process design features are briefly described relative to the gasifier, wood drying, tar separation, and process control. A test plan for process optimization and demonstration of reliability, economics, and environmental impact is outlined. (author)

  18. Biomass to energy

    International Nuclear Information System (INIS)

    This road-map proposes by the Group Total aims to inform the public on the biomass to energy. It explains the biomass principle, the possibility of biomass to energy conversion, the first generation of biofuels (bio ethanol, ETBE, bio diesel, flex fuel) and their advantages and limitations, the european regulatory framework and policy with the evolutions and Total commitments in the domain. (A.L.B.)

  19. 户用型上吸式秸秆气化炉的试验研究%Research and development on household type suction straw gasifier

    Institute of Scientific and Technical Information of China (English)

    孙友谊; 赵永亮; 李艳洁; 孙步功

    2015-01-01

    针对秸秆气化炉运行中填料时易泄露燃气、原料压实不准确、点火不均匀以及入炉空气量不合理等问题,设计了一种以玉米秸秆为原料,带有连续输料机构和原料压实机构的秸秆气化炉.实现了点火控制及入炉空气量的控制.以原料的气化量试验确定原料输入量;以原料气化强度和氧化区温度试验确定原料压实电机电流、入炉空气量及电炉丝点火时间.结果表明:螺旋旋料装置转速20 r/min 时,进料量等于秸秆消耗量;电炉丝点火10 s后通风,持续点火1 min 时达到秸秆气化点火要求;压料电机电流为0.9 A、入炉空气量为2.5 m3/h 时气化强度和产气率最佳.试验研究对气化炉优化和改进具有指导意义.%In order to solve the problems of straw gasifier such as packing easy to leak,raw material compaction unaccurate,gas ignition ununiform,into the air volume unreasonable.A new straw gasifier is designed with corn straw as the raw material,with continuous feeding mechanism and raw material compac-tion mechanism.The control of ignition and amount of air into the straw gasifier are improved.Input of raw materials is determined by amount of raw materials of gasification.In biomass gasification strength and oxi-dation temperature are determined by the compressive strength of raw materials,air flux and electric stove wire into the ignition time.The results show that Spiral screw feeder rotate 20 r/min.The rotation rate of consumption is equal to the straw.Pressure feed motor current is 0.9 A.Charging air volume of 2.5 m3/h when gasification intensity and gas rate is the optimum.Electric stove wire fire ventilation after 10 s.Con-tinuous ignition 1 min to gasification ignition requirements.Experimental study of gafier has guiding signif-icance for further optimization and improvement.

  20. Process for treating biomass

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, Timothy J; Teymouri, Farzaneh

    2015-11-04

    This invention is directed to a process for treating biomass. The biomass is treated with a biomass swelling agent within the vessel to swell or rupture at least a portion of the biomass. A portion of the swelling agent is removed from a first end of the vessel following the treatment. Then steam is introduced into a second end of the vessel different from the first end to further remove swelling agent from the vessel in such a manner that the swelling agent exits the vessel at a relatively low water content.

  1. Process for treating biomass

    Science.gov (United States)

    Campbell, Timothy J.; Teymouri, Farzaneh

    2015-08-11

    This invention is directed to a process for treating biomass. The biomass is treated with a biomass swelling agent within the vessel to swell or rupture at least a portion of the biomass. A portion of the swelling agent is removed from a first end of the vessel following the treatment. Then steam is introduced into a second end of the vessel different from the first end to further remove swelling agent from the vessel in such a manner that the swelling agent exits the vessel at a relatively low water content.

  2. 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.

  3. Experimental Investigation and Techno Economic Analysis of open Core Gasifier By Using shredded Cotton Stalk as feedstock

    Directory of Open Access Journals (Sweden)

    U. D. Dobariya*

    2016-04-01

    Full Text Available Investigation on gasification of shredded cotton stalk was carried out by developing an open core throat less downdraft gasifier reactor (capacity: 70 MJh-1.Performance of the gasifier was carried out at six different gas flow rate (12, 14, 16, 18, 20 and 22 m3/hlevels.The gasifier performed best at 18 m3h-1gas flow rate with equivalence ratio,gasification efficiency, specific gasification rate,specific gas production rate and fuel consumption rate of 0.35, 71.05 %, 192.51 kgh-1m-2,481.28m3h-1m-2and 7.2 kgh-1respectively. The economic analysis was carried out by considering shredded cotton stalk as feed stalk and compared with briquette. The benefit cost ratio of the gasifier systemwas increased from 1.45 to 2.18 (50.34% and payback period decreased from 5y9m to 3y 5m (40.39 % considering shredded cotton stalk as feed stock and compared with briquette for (gas flow rate: 18 m3h-1, daily operation: 20 h per day 270 days of operation per year.

  4. High temperature electrolyte supported Ni-GDC/YSZ/LSM SOFC operation on two-stage Viking gasifier product gas

    DEFF Research Database (Denmark)

    Hofmann, P.; Schweiger, A.; Fryda, L.;

    2007-01-01

    This paper presents the results from a 150 h test of a commercial high temperature single planar solid oxide fuel cell (SOFC) operating on wood gas from the Viking two-stage fixed-bed downdraft gasifier, which produces an almost tar-free gas, that was further cleaned for particulates, sulphur and...

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

    International Nuclear Information System (INIS)

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

  6. Performance evaluation of an integrated small-scale SOFC-biomass gasification power generation system

    Science.gov (United States)

    Wongchanapai, Suranat; Iwai, Hiroshi; Saito, Motohiro; Yoshida, Hideo

    2012-10-01

    The combination of biomass gasification and high-temperature solid oxide fuel cells (SOFCs) offers great potential as a future sustainable power generation system. In order to provide insights into an integrated small-scale SOFC-biomass gasification power generation system, system simulation was performed under diverse operating conditions. A detailed anode-supported planar SOFC model under co-flow operation and a thermodynamic equilibrium for biomass gasification model were developed and verified by reliable experimental and simulation data. The other peripheral components include three gas-to-gas heat exchangers (HXs), heat recovery steam generator (HRSG), burner, fuel and air compressors. To determine safe operating conditions with high system efficiency, energy and exergy analysis was performed to investigate the influence through detailed sensitivity analysis of four key parameters, e.g. steam-to-biomass ratio (STBR), SOFC inlet stream temperatures, fuel utilization factor (Uf) and anode off-gas recycle ratio (AGR) on system performance. Due to the fact that SOFC stack is accounted for the most expensive part of the initial investment cost, the number of cells required for SOFC stack is economically optimized as well. Through the detailed sensitivity analysis, it shows that the increase of STBR positively affects SOFC while gasifier performance drops. The most preferable operating STBR is 1.5 when the highest system efficiencies and the smallest number of cells. The increase in SOFC inlet temperature shows negative impact on system and gasifier performances while SOFC efficiencies are slightly increased. The number of cells required for SOFC is reduced with the increase of SOFC inlet temperature. The system performance is optimized for Uf of 0.75 while SOFC and system efficiencies are the highest with the smallest number of cells. The result also shows the optimal anode off-gas recycle ratio of 0.6. Regarding with the increase of anode off-gas recycle ratio

  7. Imperium/Lanzatech Syngas Fermentation Project - Biomass Gasification and Syngas Conditioning for Fermentation Evaluation: Cooperative Research and Development Final Report, CRADA Number CRD-12-474

    Energy Technology Data Exchange (ETDEWEB)

    Wilcox, E.

    2014-09-01

    LanzaTech and NREL will investigate the integration between biomass gasification and LanzaTech's proprietary gas fermentation process to produce ethanol and 2,3-butanediol. Using three feed materials (woody biomass, agricultural residue and herbaceous grass) NREL will produce syngas via steam indirect gasification and syngas conditioning over a range of process relevant operating conditions. The gasification temperature, steam-to-biomass ratio of the biomass feed into the gasifier, and several levels of syngas conditioning (based on temperature) will be varied to produce multiple syngas streams that will be fed directly to 10 liter seed fermenters operating with the Lanzatech organism. The NREL gasification system will then be integrated with LanzaTech's laboratory pilot unit to produce large-scale samples of ethanol and 2,3-butanediol for conversion to fuels and chemicals.

  8. Improved yield parameters in catalytic steam gasification of forestry residue; optimizing biomass feed rate and catalyst type

    Energy Technology Data Exchange (ETDEWEB)

    Corujo, Andrea; Yerman, Luis; Arizaga, Beatriz; Brusoni, Mariana; Castiglioni, Jorge [Laboratorio de Fisicoquimica de Superficies, DETEMA Facultad de Quimica, Universidad de la Republica, Gral. Flores 2124, CC 1157, 11800-Montevideo (Uruguay)

    2010-12-15

    The catalytic gasification (900 C) of forestry industry residue (Eucalyptus saligna) was laboratory-studied. Biomass feed rate and type and amount of catalyst were assayed for their effect on the gasified product composition and the overall energy yield of the gasification reaction. The use of a calcined dolomite catalyst resulted in a combustible gas mixture of adequate calorific power (10.65 MJ m{sup -3}) for use as fuel, but neither the product gas composition nor the energy yield varied significantly with widely different amounts of the catalyst (2 g and 20 g). The use of NiO-loaded calcined dolomite catalysts did not affect the product gas composition significantly but led to a 30% increase in the total product gas volume and to a reduction in the rate of tar and char formation. The catalyst loaded with the smallest amount of NiO studied (0.4 wt%. Ni/Dol) led to the highest energy yield (21.50 MJ kg{sup -1} on a dry-wood basis) based on the use of the gasified product as fuel. The gasified product was found to have an adequate H{sub 2}/CO molar ratio and H{sub 2} content for use as synthesis gas source and partial source of H{sub 2}. (author)

  9. Crystallization of synthetic coal-petcoke slag mixtures simulating those encountered in entrained bed slagging gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Jinichiro Nakano; Seetharaman Sridhar; Tyler Moss; James Bennett; Kyei-Sing Kwong [National Energy Technology Laboratory, Pittsburgh, PA (United States)

    2009-09-15

    Commercial entrained bed slagging gasifiers use a carbon feedstock of coal, petcoke, or combinations of them to produce CO and H{sub 2}. These carbon sources contain mineral impurities that liquefy during gasification and flow down the gasification sidewall, interacting with the refractory linear and solidifying in the cooler zones of the gasifier. Proper slag flow is critical to good gasifier operation. A hot-stage confocal scanning laser microscope (CSLM) was used to analyze the kinetic behavior of slag crystallization for a range of synthetic coal-petcoke mixtures. On the basis of the observed precipitation during cool down studies in the 1200-1700{sup o}C temperature range, a time-temperature-transformation (TTT) diagram was created. The crystallization studies were conducted with a CO/CO{sub 2} (=1.8) corresponding to a gasification PO{sub 2} of approximately 10-8 atm at 1500{sup o}C. Ash chemistries were chosen such that they correspond to coal-petcoke feedstock mixtures with coal ash amounts of 0, 10, 30, 50, 70, and 100% (by weight), with the balance being petcoke ash. The TTT diagram exhibited two crystallization areas, one above and one below 1350{sup o}C. At the nose of the higher temperature curves, karelianite (V{sub 2}O{sub 3}) crystallization occurred and was fastest for a 30% coal-petcoke ash mixture. The second nose was located below 1350{sup o}C and had spinel-type phases that formed at 1200{sup o}C, in which preferred atomic occupation at the octahedral and tetrahedral sites varied depending upon the ash composition. At 1200{sup o}C, an Al-rich spinel formed for 100% coal slag and a Fe-rich spinel formed in petcoke-enriched slags. The addition of petcoke ash to coal ash promoted crystallization in the slag, with additional crystalline phases, such as V-rich spinel, forming at the lower temperatures. These phases were not predicted using commercially available databases. 30 refs., 18 figs.

  10. Co-combustion of gasified contaminated waste wood in a coal fired power plant

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    This project demonstrates the technical and economical feasibility of the producing and cofiring of product gas from demolition waste wood. For this purpose LCV product gas is generated in an atmospheric circulating fluidized bed (CFB) gasification plant, cooled and cleaned and transported to the boiler of a 600 MWe pulverized coal fired power plant. Gas cooling and cleaning takes place in a waste heat boiler and a multi stage wet gas cleaning train. Steam raised in the waste heat boiler is exported to the power plant. On an annual basis 70,000 tons of steam coal are substituted by 150,000 tons of contaminated demolition waste wood (50,000 tons oil equivalent), resulting in a net CO2 emission reduction of 170,000 tons per year, while concurrently generating 205 GWh of electrical power. The wood gasification plant was built by NV EPZ (now incorporated in Essent Energi BV) for Amergas BV, now a 100% subsidiary of Essent Energie BV. The gasification plant is located at the Amer Power Station of NV EPZ Production (now Essent Generation) at Geertruidenberg, The Netherlands. Demonstrating several important design features in wood gasification, the plant started hot service in the Spring of 2000, with first gasification accomplished in the Summer of 2000 and is currently being optimized. (au)

  11. Exergy analysis and optimization of a biomass gasification, solid oxide fuel cell and micro gas turbine hybrid system

    DEFF Research Database (Denmark)

    Bang-Møller, Christian; Rokni, Masoud; Elmegaard, Brian

    2011-01-01

    A hybrid plant producing combined heat and power (CHP) from biomass by use of a two-stage gasification concept, solid oxide fuel cells (SOFC) and a micro gas turbine was considered for optimization. The hybrid plant represents a sustainable and efficient alternative to conventional decentralized...... CHP plants. A clean product gas was produced by the demonstrated two-stage gasifier, thus only simple gas conditioning was necessary prior to the SOFC stack. The plant was investigated by thermodynamic modeling combining zero-dimensional component models into complete system-level models. Energy and...

  12. 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

  13. World wide biomass resources

    NARCIS (Netherlands)

    Faaij, A.P.C.

    2012-01-01

    In a wide variety of scenarios, policy strategies, and studies that address the future world energy demand and the reduction of greenhouse gas emissions, biomass is considered to play a major role as renewable energy carrier. Over the past decades, the modern use of biomass has increased rapidly in

  14. Hydrothermal conversion of biomass

    NARCIS (Netherlands)

    Knezevic, Dragan

    2009-01-01

    This thesis presents research of hydrothermal conversion of biomass (HTC). In this process, hot compressed water (subcritical water) is used as the reaction medium. Therefore this technique is suitable for conversion of wet biomass/ waste streams. By working at high pressures, the evaporation of wat

  15. Bulk chemicals from biomass

    NARCIS (Netherlands)

    Haveren, van J.; Scott, E.L.; Sanders, J.P.M.

    2008-01-01

    Given the current robust forces driving sustainable production, and available biomass conversion technologies, biomass-based routes are expected to make a significant impact on the production of bulk chemicals within 10 years, and a huge impact within 20-30 years. In the Port of Rotterdam there is a

  16. Nucla CFB Demonstration Project

    Energy Technology Data Exchange (ETDEWEB)

    1990-12-01

    This report documents Colorado-Ute Electric Association's Nucla Circulating Atmospheric Fluidized-Bed Combustion (AFBC) demonstration project. It describes the plant equipment and system design for the first US utility-size circulating AFBC boiler and its support systems. Included are equipment and system descriptions, design/background information and appendices with an equipment list and selected information plus process flow and instrumentation drawings. The purpose of this report is to share the information gathered during the Nucla circulating AFBC demonstration project and present it so that the general public can evaluate the technical feasibility and cost effectiveness of replacing pulverized or stoker-fired boiler units with circulating fluidized-bed boiler units. (VC)

  17. Hydrothermal liquefaction of biomass

    DEFF Research Database (Denmark)

    Toor, Saqib; Rosendahl, Lasse; Rudolf, Andreas

    2011-01-01

    dehydration or decarboxylation. The chemical properties of bio-oil are highly dependent of the biomass substrate composition. Biomass constitutes of various components such as protein; carbohydrates, lignin and fat, and each of them produce distinct spectra of compounds during hydrothermal liquefaction. In......This article reviews the hydrothermal liquefaction of biomass with the aim of describing the current status of the technology. Hydrothermal liquefaction is a medium-temperature, high-pressure thermochemical process, which produces a liquid product, often called bio-oil or bi-crude. During the...... hydrothermal liquefaction process, the macromolecules of the biomass are first hydrolyzed and/or degraded into smaller molecules. Many of the produced molecules are unstable and reactive and can recombine into larger ones. During this process, a substantial part of the oxygen in the biomass is removed by...

  18. Termisk forgasning af biomasse

    DEFF Research Database (Denmark)

    Henriksen, Ulrik Birk

    2005-01-01

    The title of this Ph.D. thesis is: Thermal Gasification of Biomass. Compilation of activities in the ”Biomass Gasification Group” at Technical University of Denmark (DTU). This thesis gives a presentation of selected activities in the Biomass Gasification Group at DTU. The activities are related to...... thermal gasification of biomass. Focus is on gasification for decentralised cogeneration of heat and power, and on related research on fundamental processes. In order to insure continuity of the presentation the other activities in the group, have also been described. The group was started in the late...... nineteen eighties. Originally, the main aim was to collect and transfer knowledge about gasification of straw. Very quickly it became clear, that knowledge was insufficient and the available technology, in most cases, unsuitable for converting the Danish biomass. The need for such technology was...

  19. Remarks on energetic biomass

    International Nuclear Information System (INIS)

    The authors report a study of energy biomass by considering its three main sources (forest, agriculture and wastes) and three energy needs (heat, fuel for transports, electricity) in the French national context. After having recalled the various uses of biomass (animal feeding, energy production, materials, chemical products), the authors discuss the characteristics of biomass with respect to other energy sources. Then, they analyse and discuss the various energy needs which biomass could satisfy: heat production (in industry, in the residential and office building sector), fuel for transports, electricity production. They assess and discuss the possible biomass production of its three main sources: forest, agriculture, and wastes (household, agricultural and industrial wastes). They also discuss the opportunities for biogas production and for second generation bio-fuel production

  20. Rheology of concentrated biomass

    Science.gov (United States)

    Samaniuk, J. R.; Wang, J.; Root, T. W.; Scott, C. T.; Klingenberg, D. J.

    2011-12-01

    Economic processing of lignocellulosic biomass requires handling the biomass at high solids concentration. This creates challenges because concentrated biomass behaves as a Bingham-like material with large yield stresses. Here we employ torque rheometry to measure the rheological properties of concentrated lignocellulosic biomass (corn stover). Yield stresses obtained using torque rheometry agree with those obtained using other rheometric methods, but torque rheometry can be used at much larger solids concentration (weight fractions of insoluble solids greater than 0.2). Yield stresses decrease with severity of hydrolysis, decrease when water-soluble polymers are added (for nonhydrolyzed biomass), and increase with particle length. Experimental results are qualitatively consistent with those obtained from particle-level simulations.