#### Sample records for bed biomass gasification

1. 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

2. 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.)

3. Biofluid process: fluidised-bed gasification of biomass

Energy Technology Data Exchange (ETDEWEB)

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

1996-12-31

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

4. Mathematical modelling and optimization of biomass-plastic fixed-bed downdraft co-gasification process

Science.gov (United States)

Donskoy, Igor

2017-10-01

Co-gasification of woody biomass and polyethylene is studied using mathematical modeling. The gasification process is downdraft fixed-bed. Comparison of modeling results with some experimental data is made. Influence of biomass/plastic ratio and air equivalence ratio on gasification efficiency is investigated.

5. Mathematical modelling and optimization of biomass-plastic fixed-bed downdraft co-gasification process

Directory of Open Access Journals (Sweden)

Donskoy Igor

2017-01-01

Full Text Available Co-gasification of woody biomass and polyethylene is studied using mathematical modeling. The gasification process is downdraft fixed-bed. Comparison of modeling results with some experimental data is made. Influence of biomass/plastic ratio and air equivalence ratio on gasification efficiency is investigated.

6. Study on biomass pyrolysis and gasification in a fluidized bed

Energy Technology Data Exchange (ETDEWEB)

Su, X.; Wang, Z.; Cheng, C.; Tang, S.; Lu, Z.; Li, D. [Tsinghua University, Beijing (China). Thermal Engineering Department

2000-08-01

Experimental investigations of biomass pyrolysis and gasification were performed in a fluidized bed reactor with steam and nitrogen as fluid medium respectively. The size of the stainless steel reactor is 150mm ID and 1360mm in height. Five biomass samples including poplar sawdust, bagasse, cotton stem, eucalyptus globulus and pinus ratiata, have been tested on the facility at the temperatures ranging from 923K to 1073K. During each test run, biomass feedstock was fed into the reactor continuously for twelve minutes and without residue discharge, meanwhile seven gas samples were taken, five during the feeding process and two after the stop of feeding. The transient and accumulated gas yields were measured with a rotameter and a gas meter. The temperatures of the fluidized bed and freeboard were acquired by a system of thermocouples connected with a computer. The gas samples were analyzed on a gas chromatograph. On the basis of the experimental results, the variations of gas yield, gas composition, energy conversion efficiency and mass conversion efficiency with temperature are discussed for each biomass feedstock in both cases of steam and nitrogen fluidization. It has been revealed in this investigation that the presence of steam in the fluidized bed reactor stimulates tar cracking to form the gas species of C{sub 2}H{sub 4}and C{sub 2}H{sub 6}, etc. 8 ref., 15 figs., 6 tabs.

7. Mathematical Modelling of the Fixed-Bed Biomass-Coal Co-Gasification Process

Directory of Open Access Journals (Sweden)

Donskoy Igor G.

2016-01-01

Full Text Available The paper considers mathematical modelling of downdraft fixed-bed gasification process of the mixtures of woody biomass and coal. Biomass/coal ratio, biomass moisture content and air equivalence ratio are varying parameters. Boundaries of the efficient gasification regimes are estimated.

8. Modeling Tar Recirculation in Biomass Fluidized Bed Gasification

NARCIS (Netherlands)

Heineken, Wolfram; De la Cuesta de Cal, Daniel; Zobel, Nico

2016-01-01

A biomass gasification model is proposed and applied to investigate the benefits of tar recirculation within a gasification plant. In the model, tar is represented by the four species phenol, toluene, naphthalene, and benzene. The model is spatially one-dimensional, assuming plug flow for the

9. 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)

10. 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...

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

Energy Technology Data Exchange (ETDEWEB)

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

1998-09-01

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

12. Transient Catalytic Activity of Calcined Dolomitic Limestone in a Fluidized Bed during Gasification of Woody Biomass.

Czech Academy of Sciences Publication Activity Database

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

2016-01-01

Roč. 30, č. 5 (2016), s. 4065-4071 ISSN 0887-0624 R&D Projects: GA ČR GC14-09692J Institutional support: RVO:67985858 Keywords : fluidized- bed gasification * woody biomass * limestone Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 3.091, year: 2016

13. Non-slag co-gasification of biomass and coal in entrained-bed furnace

Science.gov (United States)

Itaya, Yoshinori; Suami, Akira; Kobayashi, Nobusuke

2018-02-01

Gasification is a promising candidate of processes to upgrade biomass and to yield clean gaseous fuel for utilization of renewable energy resources. However, a sufficient amount of biomass is not always available to operate a large scale of the plant. Co-gasification of biomass with coal is proposed as a solution of the problem. Tar emission is another subject during operation in shaft or kiln type of gasifiers employed conventionally for biomass. The present authors proposed co-gasification of biomass and coal in entrained-bed furnace, which is a representative process without tar emission under high temperature, but operated so to collect dust as flyash without molten slag formation. This paper presents the works performed on co-gasification performance of biomass and pulverized coal to apply to entrained-bed type of furnaces. At first, co-gasification of woody powder and pulverized coal examined using the lab-scale test furnace of the down-flow entrained bed showed that the maximum temperatures in the furnace was over 1500 K and the carbon conversion to gas achieved at higher efficiency than 80-90 percent although the residence time in the furnace was as short as a few seconds. Non-slag co-gasification was carried out successfully without slag formation in the furnace if coal containing ash with high fusion temperature was employed. The trend suggesting the effect of reaction rate enhancement of co-gasification was also observed. Secondary, an innovative sewage sludge upgrading system consisting of self-energy recovery processes was proposed to yield bio-dried sludge and to sequentially produce char without adding auxiliary fuel. Carbonization behavior of bio-dried sludge was evaluated through pyrolysis examination in a lab-scale quartz tube reactor. The thermal treatment of pyrolysis of sludge contributed to decomposition and removal of contaminant components such as nitrogen and sulfur. The gasification kinetics of sludge and coal was also determined by a

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

Energy Technology Data Exchange (ETDEWEB)

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

2013-07-01

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

15. Steam-air fluidized bed gasification of distillers grains: Effects of steam to biomass ratio, equivalence ratio and gasification temperature.

Science.gov (United States)

Kumar, Ajay; Eskridge, Kent; Jones, David D; Hanna, Milford A

2009-03-01

In this study, thermochemical biomass gasification was performed on a bench-scale fluidized-bed gasifier with steam and air as fluidizing and oxidizing agents. Distillers grains, a non-fermentable byproduct of ethanol production, were used as the biomass feedstock for the gasification. The goal was to investigate the effects of furnace temperature, steam to biomass ratio and equivalence ratio on gas composition, carbon conversion efficiency and energy conversion efficiency of the product gas. The experiments were conducted using a 3x3x3 full factorial design with temperatures of 650, 750 and 850 degrees C, steam to biomass ratios of 0, 7.30 and 14.29 and equivalence ratios of 0.07, 0.15 and 0.29. Gasification temperature was found to be the most influential factor. Increasing the temperature resulted in increases in hydrogen and methane contents, carbon conversion and energy efficiencies. Increasing equivalence ratio decreased the hydrogen content but increased carbon conversion and energy efficiencies. The steam to biomass ratio was optimal in the intermediate levels for maximal carbon conversion and energy efficiencies.

16. Experimental study of biomass gasification with oxygen-enriched air in fluidized bed gasifier.

Science.gov (United States)

Liu, Lingqin; Huang, Yaji; Cao, Jianhua; Liu, Changqi; Dong, Lu; Xu, Ligang; Zha, Jianrui

2018-06-01

Considering the universality, renewability and cleanness of biomass, an experimental research is carried out using rice straw in a two-stage fluidized bed. The experimental analysis identified the relevant parameters in the operation of the two-stage fluidized bed to investigate the properties of biomass enriched air gasification. Results show that higher gasification temperature is conducive to enhance the gasification performance. An increasing ER is shown to go against adding gas heat value. When oxygen concentration increases from 21% to 45%, the gas heating value increases from 4.00MJ/kg to 5.24MJ/kg and the gasification efficiency increases from 29.60% to 33.59%, which shows higher oxygen concentration is conducive to higher quality gas and higher gasification efficiency. A secondary oxygen injection leads to reduction of tar concentration from 15.78g/Nm 3 to 10.24g/Nm 3 . The optimal secondary oxygen ratio is about 33.00%. When the secondary oxygen ratio increased to 46.86%, monocyclic aromatics reduced from 28.17% to 19.65% and PAHs increased from 34.97% to 44.05%, leading to the increase aromatization of tar. Copyright © 2018 Elsevier B.V. All rights reserved.

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. Generation of hydrogen rich gas through fluidized bed gasification of biomass.

Science.gov (United States)

Karmakar, M K; Datta, A B

2011-01-01

The objective of this study was to investigate the process of generating hydrogen rich syngas through thermo chemical fluidized bed gasification of biomass. The experiments were performed in a laboratory scale externally heated biomass gasifier. Rice husk had been taken as a representative biomass and, steam had been used as the fluidizing and gasifying media. A thermodynamic equilibrium model was used to predict the gasification process. The work included the parametric study of process parameters such as reactor temperature and steam biomass ratio which generally influence the percentage of hydrogen content in the product gas. Steam had been used here to generate nitrogen free product gas and also to increase the hydrogen concentration in syngas with a medium range heating value of around 12 MJ/Nm3. Copyright Â© 2010 Elsevier Ltd. All rights reserved.

19. Air-steam gasification of biomass in a fluidised bed: Process optimisation by enriched air

Energy Technology Data Exchange (ETDEWEB)

Campoy, Manuel; Gomez-Barea, Alberto; Vidal, Fernando B.; Ollero, Pedro [Bioenergy Group, Chemical and Environmental Engineering Department, Escuela Superior de Ingenieros (University of Seville), Camino de los Descubrimientos s/n. 41092 - Seville (Spain)

2009-05-15

The effect of oxygen concentration in the gasification agent was studied by enriched-air-steam biomass gasification tests in a bubbling fluidised-bed gasification (FBG) plant. The oxygen content in the enriched air was varied from 21% (v/v, i.e. air) to 40% (v/v), aiming at simulating FBG where enriched air is produced by membranes. The stoichiometric ratio (ratio of actual to stoichiometric oxygen flow rates) and steam-to-biomass ratio (ratio of steam to biomass, dry and ash-free, flow rates) were varied from 0.24 to 0.38 and from 0 to 0.63, respectively. The tests were conducted under simulated adiabatic and autothermal conditions, to reproduce the behaviour of larger industrial FBG. The temperature of the inlet gasification mixture was fixed consistently at 400 C for all tests, a value that can be achieved by energy recovery from the off-gas in large FBG without tar condensation. It was shown that the enrichment of air from 21 to 40% v/v made it possible to increase the gasification efficiency from 54% to 68% and the lower heating value of the gas from 5 to 9.3 MJ/Nm{sup 3}, while reaching a maximum carbon conversion of 97%. The best conditions were found at intermediate values of steam-to-biomass ratio, specifically within the range 0.25-0.35. The enriched-air-steam gasification concept explored in this work seems to be an interesting option for the improvement of standalone direct air-blown FBG because it considerably improves the process efficiency while maintaining the costs relatively low as compared to oxygen-steam gasification. (author)

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

Science.gov (United States)

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

2014-10-01

Thermo-chemical gasification of sawdust refuse-derived fuel was performed on a bench-scale fluidised bed gasifier with enriched air and steam as fluidising and oxidising agents. Dolomite as a natural mineral catalyst was used as bed material to reform tars and hydrocarbons. A series of experiments were carried out under typical operating conditions for gasification, as reported in the article. A modified equilibrium model, based on equilibrium constants, was developed to predict the gasification process. The sensitivity analysis of operating parameters, such as the fluidisation velocity, oxygen percentage of the enriched air and steam to biomass ratios on the produced gas composition, lower heating value, carbon conversion and cold gas efficiency was investigated. The results showed that the predicted syngas composition was in better agreement with the experimental data compared with the original equilibrium model. The higher fluidisation velocity enhanced gas-solid mixing, heat and mass transfers, and carbon fines elutriation, simultaneously. With the increase of oxygen percentage from 21% to 45%, the lower heating value of syngas increased from 5.52 MJ m(-3) to 7.75 MJ m(-3) and cold gas efficiency from 49.09% to 61.39%. The introduction of steam improved gas quality, but a higher steam to biomass ratio could decrease carbon conversion and gasification efficiency owing to a low steam temperature. The optimal value of steam to biomass ratio in this work was 1.0. © The Author(s) 2014.

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

NARCIS (Netherlands)

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

2. Gas generation by co-gasification of biomass and coal in an autothermal fluidized bed gasifier

International Nuclear Information System (INIS)

Wang, Li-Qun; Chen, Zhao-Sheng

2013-01-01

In this study, thermochemical biomass and coal co-gasification were performed on an autothermal fluidized bed gasifier, with air and steam as oxidizing and gasifying media. The experiments were completed at reaction temperatures of 875 °C–975 °C, steam-to-biomass ratio of 1.2, and biomass-to-coal ratio of 4. This research aims to determine the effects of reaction temperature on gas composition, lower heating value (LHV), as well as energy and exergy efficiencies, of the product gas. Over the ranges of the test conditions used, the product gas LHV varies between 12 and 13.8 MJ/Nm 3 , and the exergy and energy efficiencies of the product gas are in the ranges of 50.7%–60.8% and 60.3%–85.1%, respectively. The results show that high reaction temperature leads to higher H 2 and CO contents, as well as higher exergy and energy efficiencies of the product gas. In addition, gas LHV decreases with temperature. The molar ratio of H 2 /CO is larger than 1 at temperatures above 925 °C. Our experimental analysis shows that co-gasification of biomass and coal in an autothermal fluidized bed gasifier for gas production is feasible and promising. -- Highlights: • An innovative steam co-gasification process for gas production was proposed. • Co-gasification of biomass and coal in an autothermal fluidized bed gasifier was tested. • High temperature favors H 2 production. • H 2 and CO contents increase, whereas CO 2 and CH 4 levels decrease with increase in T. • Exergy and energy efficiencies of gases increase with increase in T

3. Gasification of biomass in a fixed bed downdraft gasifier--a realistic model including tar.

Science.gov (United States)

Barman, Niladri Sekhar; Ghosh, Sudip; De, Sudipta

2012-03-01

This study presents a model for fixed bed downdraft biomass gasifiers considering tar also as one of the gasification products. A representative tar composition along with its mole fractions, as available in the literature was used as an input parameter within the model. The study used an equilibrium approach for the applicable gasification reactions and also considered possible deviations from equilibrium to further upgrade the equilibrium model to validate a range of reported experimental results. Heat balance was applied to predict the gasification temperature and the predicted values were compared with reported results in literature. A comparative study was made with some reference models available in the literature and also with experimental results reported in the literature. Finally a predicted variation of performance of the gasifier by this validated model for different air-fuel ratio and moisture content was also discussed. Copyright © 2011 Elsevier Ltd. All rights reserved.

4. Design and simulation of a circulating fluidized bed to clean the products of biomass gasification

Energy Technology Data Exchange (ETDEWEB)

Uchoa Neto, Moises; Carvalho, Yuri de Araujo [Dept. de Engenharia Mecanica. Faculdade de Tecnologia. Universidade de Brasilia, DF (Brazil); Oliveira, Taygoara Felamingo de; Barcelos, Manuel [Faculdade do Gama. Universidade de Brasilia, Gama, DF (Brazil)], e-mail: taygoara@unb.br

2010-07-01

The main goal of this work is to design a workbench circulating fluidized bed to study the cracking of tar in gases from the processes of biomass gasification. For this, a design methodology based on analytical results and empirical correlations for fluidized beds was employed. In parallel, a numerical code of open source technology (MFIX) for the solution of the transport equations of the multiphase flow in the column of a fluidized bed was used to give support to the choice of the design elements. The whole project of the workbench fluidized bed was completely developed, whose operation parameters such as bed geometry, gas velocity, circulating ratio and void fraction characterize a fast fluidization process. A preliminary mesh convergence study was executed with the numerical tool, that was validated comparing with analytical results. Among the most important results, the code computed the predicted value for the minimum fluidization. (author)

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

Energy Technology Data Exchange (ETDEWEB)

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

2009-03-15

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

6. 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)

7. H₂-rich syngas production by fluidized bed gasification of biomass and plastic fuel.

Science.gov (United States)

Ruoppolo, G; Ammendola, P; Chirone, R; Miccio, F

2012-04-01

This paper reports the results of gasification tests using a catalytic fluidized bed gasifier to obtain a H(2)-rich stream by feeding different pellets made of wood, biomass/plastic and olive husks to the gasifier. The effects of both the steam supply and an in-bed catalyst on gasifier performance have been investigated. In general, pelletization was an effective pre-treatment for improving the homogeneity of the fuel and the reliability of the feeding devices. The use of biomass/plastic pellets in a catalyst bed yielded good results in terms of the hydrogen concentration (up to 32%vol.), even if an increase in tar production and in the fine/carbon elutriation rate was observed in comparison with wood pellets. Copyright Â© 2011 Elsevier Ltd. All rights reserved.

8. Simulation of biomass-steam gasification in fluidized bed reactors: Model setup, comparisons and preliminary predictions.

Science.gov (United States)

Yan, Linbo; Lim, C Jim; Yue, Guangxi; He, Boshu; Grace, John R

2016-12-01

A user-defined solver integrating the solid-gas surface reactions and the multi-phase particle-in-cell (MP-PIC) approach is built based on the OpenFOAM software. The solver is tested against experiments. Then, biomass-steam gasification in a dual fluidized bed (DFB) gasifier is preliminarily predicted. It is found that the predictions agree well with the experimental results. The bed material circulation loop in the DFB can form automatically and the bed height is about 1m. The voidage gradually increases along the height of the bed zone in the bubbling fluidized bed (BFB) of the DFB. The U-bend and cyclone can separate the syngas in the BFB and the flue gas in the circulating fluidized bed. The concentration of the gasification products is relatively higher in the conical transition section, and the dry and nitrogen-free syngas at the BFB outlet is predicted to be composed of 55% H 2 , 20% CO, 20% CO 2 and 5% CH 4 . Copyright © 2016 Elsevier Ltd. All rights reserved.

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

Energy Technology Data Exchange (ETDEWEB)

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

1996-12-31

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

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

Energy Technology Data Exchange (ETDEWEB)

Hannula, I.; Kurkela, E.

2013-04-15

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

11. The effect of Jatropha torrified biomass and coal preparation on steam co-gasification in a fixed bed reactor

Science.gov (United States)

Aloqaili, Mashal Mohammed

Coal fired power stations produce vast amounts of harmful products that may affect our health and environment. Co-gasification of coal and biomass could be a solution to this issue as an emerging technology. Biomass may reduce emissions significantly and it may contribute to reducing capital operational cost while providing high gas yields. This research tests the co-gasification of coal and biomass blended chars. Coal and biomass were both prepared. Coal Illinois No #6 was prepared as coal semi-char and coal-char while Jatropha biomass was torrefied at six different temperatures ranging from [200-300] ºC. The co-gasification experiments was conducted in a fixed-bed reactor. A gasification temperature was 900 ºC and a constant flow rate of 100 mL/min. Carbon conversion, maximum char reactivity, products yield and amount of hydrogen produced were evaluated and studied based on data obtained from the G.C. Additionally, weight of bed material and ash leftover weight from gasification process were significantly contributed in calculating the carbon conversion percentages.

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

International Nuclear Information System (INIS)

Rojas Mazaira, Leorlen Y.; Gamez Rodriguez, Abel; Andrade Gregori, Maria Dolores; Armas Cardona, Raul

2009-01-01

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

13. Allothermal steam gasification of biomass in cyclic multi-compartment bubbling fluidized-bed gasifier/combustor - new reactor concept.

Science.gov (United States)

Iliuta, Ion; Leclerc, Arnaud; Larachi, Faïçal

2010-05-01

A new reactor concept of allothermal cyclic multi-compartment fluidized bed steam biomass gasification is proposed and analyzed numerically. The concept combines space and time delocalization to approach an ideal allothermal gasifier. Thermochemical conversion of biomass in periodic time and space sequences of steam biomass gasification and char/biomass combustion is simulated in which the exothermic combustion compartments provide heat into an array of interspersed endothermic steam gasification compartments. This should enhance unit heat integration and thermal efficiency and procure N(2)-free biosyngas with recourse neither to oxygen addition in steam gasification nor contact between flue and syngas. The dynamic, one-dimensional, multi-component, non-isothermal model developed for this concept accounts for detailed solid and gas flow dynamics whereupon gasification/combustion reaction kinetics, thermal effects and freeboard-zone reactions were tied. Simulations suggest that allothermal operation could be achieved with switch periods in the range of a minute supporting practical feasibility for portable small-scale gasification units. Copyright 2009 Elsevier Ltd. All rights reserved.

14. 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...

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

Czech Academy of Sciences Publication Activity Database

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

2008-01-01

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

16. Gasification of Woody Biomass.

Science.gov (United States)

Dai, Jianjun; Saayman, Jean; Grace, John R; Ellis, Naoko

2015-01-01

Interest in biomass to produce heat, power, liquid fuels, hydrogen, and value-added chemicals with reduced greenhouse gas emissions is increasing worldwide. Gasification is becoming a promising technology for biomass utilization with a positive environmental impact. This review focuses specifically on woody biomass gasification and recent advances in the field. The physical properties, chemical structure, and composition of biomass greatly affect gasification performance, pretreatment, and handling. Primary and secondary catalysts are of key importance to improve the conversion and cracking of tars, and lime-enhanced gasification advantageously combines CO2 capture with gasification. These topics are covered here, including the reaction mechanisms and biomass characterization. Experimental research and industrial experience are investigated to elucidate concepts, processes, and characteristics of woody biomass gasification and to identify challenges.

17. Study on biomass circulation and gasification performance in a clapboard-type internal circulating fluidized bed gasifier.

Science.gov (United States)

Zhou, Zhao-qiu; Ma, Long-long; Yin, Xiu-li; Wu, Chuang-zhi; Huang, Li-cheng; Wang, Chu

2009-01-01

We investigated the solid particle flow characteristics and biomass gasification in a clapboard-type internal circulating fluidized bed reactor. The effect of fluidization velocity on particle circulation rate and pressure distribution in the bed showed that fluidization velocities in the high and low velocity zones were the main operational parameters controlling particle circulation. The maximum internal circulation rates in the low velocity zone came almost within the range of velocities in the high velocity zone, when u(H)/u(mf)=2.2-2.4 for rice husk and u(H)/u(mf)=3.5-4.5 for quartz sand. In the gasification experiment, the air equivalence ratio (ER) was the main controlling parameter. Rice husk gasification gas had a maximum heating value of around 5000 kJ/m(3) when ER=0.22-0.26, and sawdust gasification gas reached around 6000-6500 kJ/m(3) when ER=0.175-0.24. The gasification efficiency of rice husk reached a maximum of 77% at ER=0.28, while the gasification efficiency of sawdust reached a maximum of 81% at ER=0.25.

18. Biomass and fossil fuel conversion by pressurised fluidised bed gasification using hot gas ceramic filters as gas cleaning

International Nuclear Information System (INIS)

Jong, Wiebren de; Uenal, Oemer; Andries, Jans; Hein, K.R.G.; Spliethoff, Hartmut

2003-01-01

Gasification of biomass and fossil fuels, hot gas cleanup using a ceramic filter and combustion of LCV product gas in a combustor were performed using a 1.5 MWth test rig (pressurised bubbling fluidised bed gasifier) at Delft University and a 10-50 kWth system at Stuttgart University (DWSA) in the framework of experimental research on efficient, environmentally acceptable large-scale power generators based on fluidised bed gasification. The influence of operating conditions (pressure, temperature, stoichiometric ratio) on gasification (gas composition, conversion grades) was studied. The gasifiers were operated in a pressure range of 0.15-0.7 MPa and maximum temperatures of ca. 900 deg. C. The Delft gasifier has a 2 m high bed zone (diameter: 0.4 m) followed by a freeboard approximately 4 m high (diameter: 0.5 m). The IVD gasifier has a diameter of 0.1 m and a reactor length of 4 m. Carbon conversions during wood, miscanthus and brown coal gasification experiments were well above 80%. Fuel-nitrogen conversion to ammonia was above ca. 50% and the highest values were observed for biomass. The results are in line with other investigations with biomass bottom feeding. Deviation occurs compared with top feeding. Measurements are compared with simulation results of a reaction-kinetics-based model, using ASPEN PLUS, related to emission of components like fuel-nitrogen-derived species. Data from literature regarding initial biomass flash pyrolysis in the gasification process are used in the gasifier model and will be compared with simulation results from the FG-DVC model. Measurements and model predictions were in reasonably good agreement with each other

19. Catalytic Gasification of Lignocellulosic Biomass

NARCIS (Netherlands)

Chodimella, Pramod; Seshan, Kulathuiyer; Schlaf, Marcel; Zhang, Z. Conrad

2015-01-01

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

20. Biomass gasification with air in fluidized bed: hot gas cleanup and upgrading with steam-reforming catalysts of big size

Energy Technology Data Exchange (ETDEWEB)

Corella, J.; Caballero, M.A. [University Complutense, Madrid (Spain); Aznar, M.P.; Gil, J. [University of Saragossa (Spain)

1999-07-01

Several commercial steam reforming (nickel-based) catalysts were tested for tar elimination and gas upgrading in biomass gasification with air in fluidized bed. The characteristic or novelty of this work is that the catalysts are not crushed or ground but are used in their commercial size and shape. Catalysts were tested at pilot scale in two fixed beds located in a slip flow downstream from the gasifier. The equivalence ratio used in the upstream gasifier and steam content in the flue gas have an important effect on the kinetics of the tar removal reaction. (author)

1. Hydrogen production by biomass steam gasification in fluidized bed reactor with Co catalyst

International Nuclear Information System (INIS)

Kazuhiko Tasaka; Atsushi Tsutsumi; Takeshi Furusawa

2006-01-01

The catalytic performances of Co/MgO catalysts were investigated in steam gasification of cellulose and steam reforming of tar derived from cellulose gasification. For steam reforming of cellulose tar in a secondary fixed bed reactor, 12 wt.% Co/MgO catalyst attained more than 80% of tar reduction. The amount of produced H 2 and CO 2 increased with the presence of catalyst, and kept same level during 2 hr at 873 K. It is indicated that steam reforming of cellulose tar proceeds sufficiently over Co/MgO catalyst. For steam gasification of cellulose in a fluidized bed reactor, it was found that tar reduction increases with Co loading amount and 36 wt.% Co/MgO catalyst showed 84% of tar reduction. The amounts of produced gas kept for 2 hr indicating that 36 wt.% Co/MgO catalyst is stable during the reaction. It was concluded that these Co catalysts are promising systems for the steam gasification of cellulose and steam reforming of cellulose tar. (authors)

2. Biomass gasification in atmospheric and bubbling fluidized bed: effect of the type of gasifying agent on the product distribution

Energy Technology Data Exchange (ETDEWEB)

Gil, J.; Aznar, M.P.; Caballero, M.A. [University of Saragossa (Spain). Chemical and Environmental Engineering Dept.; Corella, J. [University ' ' Complutense' ' of Madrid (Spain). Chemical Engineering Dept.

1999-07-01

The effect of the type of gasifying agent used in biomass gasification on product distribution (gas, char and tar yields) and gas quality (Contents in H{sub 2}, CO, CO{sub 2}, CH{sub 4},..., tars) is analyzed. Gasifying agents taken into account are: air, pure steam, and steam-O{sub 2} mixtures. Process considered is biomass gasification in atmospheric and bubbling fluidized bed. Previous results by Herguido et al. (Ind. Eng. Chem. Res. 1992; 31(2): 1274-82), Gil et al. (Energy and Fuels 1997; 11(6): 1109-18) and Narvaez et al. (Ind. Eng. Chem. Res. 1996; 35(7): 2110-20) are compared. Such authors carried their research on biomass gasification under similar conditions but varying the gasifying agent. Three different gasifying agent-to-biomass ratios are needed and used to compare results. The relationships between the H{sub 2}, CO,..., tar contents in the flue gas and the type and amount of gasifying agent used are shown after a careful analysis. (author)

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

International Nuclear Information System (INIS)

Ising, M.; Balke, U.; Unger, C.

1999-06-01

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/m 3 (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/m 3 (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/m 3 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.) [de

4. Gasification of Biomass with CO2 and H2O Mixtures in a Catalytic Fluidised Bed.

Czech Academy of Sciences Publication Activity Database

Jeremiáš, Michal; Pohořelý, Michael; Svoboda, Karel; Manovic, V.; Anthony, E.J.; Skoblia, S.; Beňo, Z.; Šyc, Michal

2017-01-01

Roč. 210, DEC 15 (2017), s. 605-610 ISSN 0016-2361 R&D Projects: GA ČR GC14-09692J Grant - others:NSC(TW) 103-2923-E-042A-001-MY3 Institutional support: RVO:67985858 Keywords : fluidised bed * gasification * catalyst Subject RIV: JE - Non-nuclear Energetics, Energy Consumption ; Use OBOR OECD: Energy and fuels Impact factor: 4.601, year: 2016

5. Behavior of Heavy Metals in Steam Fluidized Bed Gasification of Contaminated Biomass

Czech Academy of Sciences Publication Activity Database

Šyc, Michal; Pohořelý, Michael; Jeremiáš, Michal; Vosecký, Martin; Kameníková, Petra; Skoblia, Sergej; Svoboda, Karel; Punčochář, Miroslav

2011-01-01

Roč. 25, č. 5 (2011), s. 2284-2291 ISSN 0887-0624 R&D Projects: GA ČR(CZ) GA104/07/0977; GA MŠk 2B08048 Institutional research plan: CEZ:AV0Z40720504 Keywords : gasification * heavy metals * contaminated biomass Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 2.721, year: 2011

6. High Pressure Biomass Gasification

Energy Technology Data Exchange (ETDEWEB)

Agrawal, Pradeep K [Georgia Tech Research Corporation, Atlanta, GA (United States)

2016-07-29

According to the Billion Ton Report, the U.S. has a large supply of biomass available that can supplement fossil fuels for producing chemicals and transportation fuels. Agricultural waste, forest residue, and energy crops offer potential benefits: renewable feedstock, zero to low CO2 emissions depending on the specific source, and domestic supply availability. Biomass can be converted into chemicals and fuels using one of several approaches: (i) biological platform converts corn into ethanol by using depolymerization of cellulose to form sugars followed by fermentation, (ii) low-temperature pyrolysis to obtain bio-oils which must be treated to reduce oxygen content via HDO hydrodeoxygenation), and (iii) high temperature pyrolysis to produce syngas (CO + H2). This last approach consists of producing syngas using the thermal platform which can be used to produce a variety of chemicals and fuels. The goal of this project was to develop an improved understanding of the gasification of biomass at high pressure conditions and how various gasification parameters might affect the gasification behavior. Since most downstream applications of synags conversion (e.g., alcohol synthesis, Fischer-Tropsch synthesis etc) involve utilizing high pressure catalytic processes, there is an interest in carrying out the biomass gasification at high pressure which can potentially reduce the gasifier size and subsequent downstream cleaning processes. It is traditionally accepted that high pressure should increase the gasification rates (kinetic effect). There is also precedence from coal gasification literature from the 1970s that high pressure gasification would be a beneficial route to consider. Traditional approach of using thermogravimetric analyzer (TGA) or high-pressure themogravimetric analyzer (PTGA) worked well in understanding the gasification kinetics of coal gasification which was useful in designing high pressure coal gasification processes. However

7. Biomass gasification with air in fluidized bed: Reforming of the gas composition with commercial steam reforming catalysts

Energy Technology Data Exchange (ETDEWEB)

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

1998-12-01

Four commercial catalysts for steam reforming of higher hydrocarbons (naphthas) and three for steam reforming of light hydrocarbons are tested for hot gas clean up and upgrading in biomass gasification with air in fluidized bed. The catalysts used originate from four manufacturers: BASF, AG, ICI-Katalco, Haldor Topsoe a/s, and United Catalysts Inc. The work is performed in a small pilot plant (1--2 kg of biomass fed/h) with three reactors in series: gasifier, guard bed of dolomite, and full flow catalytic bed. Samples of gas are taken before and after the catalytic bed at different times-on-stream. It is shown how the H{sub 2}, CO, CO{sub 2}, CH{sub 4} and steam contents in the flue gas change because of the catalytic bed approaching contents near to the ones corresponding to the equilibrium state. Variations in the heating value of the gas and gas yield as a result of the catalytic bed are also reported.

8. Development of a bi-equilibrium model for biomass gasification in a downdraft bed reactor.

Science.gov (United States)

Biagini, Enrico; Barontini, Federica; Tognotti, Leonardo

2016-02-01

This work proposes a simple and accurate tool for predicting the main parameters of biomass gasification (syngas composition, heating value, flow rate), suitable for process study and system analysis. A multizonal model based on non-stoichiometric equilibrium models and a repartition factor, simulating the bypass of pyrolysis products through the oxidant zone, was developed. The results of tests with different feedstocks (corn cobs, wood pellets, rice husks and vine pruning) in a demonstrative downdraft gasifier (350kW) were used for validation. The average discrepancy between model and experimental results was up to 8 times less than the one with the simple equilibrium model. The repartition factor was successfully related to the operating conditions and characteristics of the biomass to simulate different conditions of the gasifier (variation in potentiality, densification and mixing of feedstock) and analyze the model sensitivity. Copyright © 2015 Elsevier Ltd. All rights reserved.

9. Biomass gasification: Produced gas upgrading by in-bed use of dolomite

Energy Technology Data Exchange (ETDEWEB)

Olivares, A.; Aznar, M.P.; Caballero, M.A.; Gil, J.; Frances, E. [Univ. of Saragossa (Spain). Chemical and Environmental Engineering Dept.; Corella, J. [Univ. Complutense of Madrid (Spain). Chemical Engineering Dept.

1997-12-01

When some calcined dolomite (OCa{center_dot}OMg) is used in the bed of a biomass gasifier of fluidized bed type the raw gas produced is cleaner than when only silica sand is used in it as fluidizing medium. In-bed dolomite changes the product distribution at the gasifier exit because of in-situ catalytic reactions promoted by the calcined dolomite. Gasifying with steam-O{sub 2} mixtures causes the tar content in the exit gas to decrease from 12 to 2--3 g tar/m{sup 3}{sub n}, the H{sub 2} content to increase from 25--28 to 43 vol%, and the CO content to decrease from 45 to 27 vol% when the gas and char yields, heating value of the gas, and other main variables also undergo important changes because of the in-bed dolomite. The experimental work here reported is carried out at small pilot plant scale in a 15 cm i.d. atmospheric and bubbling fluidized bed gasifier fed by 10 kg biomass/h. Dolomite is continuously fed to the gasifier, mixed with the biomass in percentages of 2--3 wt% of the total mass flow fed. A 10 wt% of calcined dolomite in the gasifier bed is enough to significantly improve the product distribution and gas quality.

10. 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)

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

Energy Technology Data Exchange (ETDEWEB)

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

2008-07-01

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

12. Biomass gasification using nickel loaded brown coal char in fluidized bed gasifier at relatively low temperature

Energy Technology Data Exchange (ETDEWEB)

Le, D.D.; Xiao, X.B.; Morishita, K.; Takarada, T. [Gunma University, Gumma (Japan)

2009-07-01

Our work focuses on developing nickel loaded brown coal char as a new catalyst to decompose tar and to enhance quality of product gas delivered from woody biomass pyrolysis at relatively low temperatures of 823 K and 923 K. It is carried out in two-stage fixed-bed reactor and a lab scale fluidized bed gasifier (FBG) under various conditions. Inside of gasifier is constructed by two beds, the primary one is a fluidized bed with sand. and the second one is a catalyst bed. The catalyst bed is used to evaluate and to compare catalytic activity between the new catalyst and a conventional Ni/Al{sub 2}O{sub 3} catalyst. The new catalyst is prepared by ion exchange method, dried at 380 K in nitrogen for 24 h, and is then calcined at 923 K in nitrogen for 90 min. The temperature as a function of gas yield and the effect of catalysts on gas yield in presence and absence of steam are investigated in this study. The new catalyst has shown high catalytic activity and stable activity and given the high quality of product gas in presence of steam.

13. Biomass gasification and in-bed contaminants removal: performance of iron enriched olivine and bauxite in a process of steam/O2 gasification.

Science.gov (United States)

Barisano, D; Freda, C; Nanna, F; Fanelli, E; Villone, A

2012-08-01

A modified Olivine, enriched in iron content (10% Fe/Olivine), and a natural bauxite, were tested in the in-bed reduction of tar and alkali halides (NaCl and KCl) released in a process of biomass steam/O(2) gasification. The tests were carried out at an ICBFB bench scale reactor under the operating conditions of: 855-890 °C, atmospheric pressure, 0.5 steam/biomass and 0.33 ER ratios. From the use of the two materials, a reduction in the contaminant contents of the fuel gas produced was found. For the alkali halides, a decrease up to 70%(wt) was observed for the potassium concentration, while for sodium, the reduction was found to be quite poor. For the organic content, compared to unmodified Olivine, the chromatographically determined total tar quantity showed a removal efficiency of 38%(wt). Moreover, regarding the particulate content a rough doubling in the fuel gas revealed a certain brittleness of the new bed material. Copyright © 2012 Elsevier Ltd. All rights reserved.

14. Entrained Flow Gasification of Biomass

DEFF Research Database (Denmark)

Qin, Ke

The present Ph. D. thesis describes experimental and modeling investigations on entrained flow gasification of biomass and an experimental investigation on entrained flow cogasification of biomass and coal. A review of the current knowledge of biomass entrained flow gasification is presented....... Biomass gasification experiments were performed in a laboratory-scale atmospheric pressure entrained flow reactor with the aim to investigate the effects of operating parameters and biomass types on syngas products. A wide range of operating parameters was involved: reactor temperature, steam/carbon ratio......, excess air ratio, oxygen concentration, feeder gas flow, and residence time. Wood, straw, and lignin were used as biomass fuels. In general, the carbon conversion was higher than 90 % in the biomass gasification experiments conducted at high temperatures (> 1200 °C). The biomass carbon...

15. Biomass gasification with air in an atmospheric bubbling fluidized bed. Effect of six operational variables on the quality of the produced raw gas

Energy Technology Data Exchange (ETDEWEB)

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

1996-07-01

Biomass gasification with air in a bubbling fluidized bed is studied in a small pilot plant. Variables analyzed are equivalence ratio (from 0.20 to 0.45), temperatures of the gasifier bed (750--850 C) and of its freeboard (500--600 C), H/C ratio in the feed, use of secondary air (10% of the overall) in the freeboard, and addition (2--5 wt %) of a calcined dolomite mixed with the biomass used as the feedstock. Using advanced tar and gas sampling and analysis methods, the gas composition and tar content in the gas are determined and their variation with the operation parameters is given. A statistical analysis of the effects of the gasification variables is also here presented.

16. Gasification of algal biomass (Cladophora glomerata L.) with CO2/H2O/O2in a circulating fluidized bed.

Science.gov (United States)

Ebadi, Abdol Ghaffar; Hisoriev, Hikmat

2017-11-28

Gasification is one of the most important thermochemical routes to produce both synthesis gas (syngas) and chars. The quality of produced syngas wieldy depends on the operating conditions (temperature, residence time, heating rate, and gasifying agent), hydrodynamic properties of gasifier (particle size, minimum fluidization velocity, and gasifier size), and type of feedstock (coal, biomass, oil, and municipal solid wastes). In the present study, simulation of syngas production via circulating fluidized bed (CFB) gasification of algal biomass (Cladophora glomerata L.) at different gasifying agents and particle sizes was carried out, using Aspen Plus simulator. The model which has been validated by using experimental data of the technical literature was used to evaluate the influence of operating conditions on gas composition and performance parameters. The results show that biomass gasification using pure oxygen as the gasification agent has great potential to improve the caloric value of produced gas and performance indicators. It was also found that the produced gas caloric value, syngas yield, and performance parameters (CCE and CGE) increase with reaction temperature but are inversely proportional to the biomass particle size.

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

Science.gov (United States)

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

2015-01-01

This work studied the feasibility of co-gasification of biosolids with biomass as a means of disposal with energy recovery. The kinetics study at 800°C showed that biomass, such as switchgrass, could catalyze the reactions because switchgrass ash contained a high proportion of potassium, an excellent catalyst for gasification. However, biosolids could also inhibit gasification due to interaction between biomass alkali/alkaline earth metals and biosolids clay minerals. In the pilot scale experiments, increasing the proportion of biosolids in the feedstock affected gasification performance negatively. Syngas yield and char conversion decreased from 1.38 to 0.47m(3)/kg and 82-36% respectively as the biosolids proportion in the fuel increased from 0% to 100%. Over the same range, the tar content increased from 10.3 to 200g/m(3), while the ammonia concentration increased from 1660 to 19,200ppmv. No more than 25% biosolids in the fuel feed is recommended to maintain a reasonable gasification. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

Energy Technology Data Exchange (ETDEWEB)

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

1996-12-01

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

19. Principles of a novel multistage circulating fluidized bed reactor for biomass gasification

NARCIS (Netherlands)

Kersten, Sascha R.A.; Prins, W.; van der Drift, Bram; van Swaaij, Willibrordus Petrus Maria

2003-01-01

In this paper a novel multistage circulating fluidized bed reactor has been introduced. The riser of this multistage circulating fluidized bed consists of several segments (seven in the base-case design) in series each built-up out of two opposite cones. Due to the specific shape, a fluidized bed

20. 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)

1. Biomass oxygen/steam gasification in a pressurized bubbling fluidized bed: Agglomeration behavior

International Nuclear Information System (INIS)

Zhou, Chunguang; Rosén, Christer; Engvall, Klas

2016-01-01

Highlights: • Dolomite is a superior material in preventing bed agglomeration. • Small molten ash particles deposited on magnesite at bed temperatures above 1000 °C. • The performance, when using magnesite, is sensitive to temperature disturbances. • The anti-agglomeration mechanisms of Ca- and Mg-bearing materials were discussed. - Abstract: In this study, the anti-agglomeration abilities of Ca- and Mg-containing bed materials, including dolomite and magnesite, in a pressurized bubbling fluidized bed gasifier using pine pellets and birch chips as feedstock, is investigated. The most typical bed material—silica sand—was also included as a reference for comparison. The sustainability of the operation was evaluated via analyzing the temperatures at different levels along the bed height. During the performances, the aim was to keep the temperature at the bottom zone of the reactor at around 870 °C. However, the success highly depends on the bed materials used in the bed and the temperature can vary significantly in case of agglomeration or bad mixing of bed materials and char particles. Both Glanshammar and Sala dolomites performed well with no observed agglomeration tendencies. In case of magnesite, the bed exhibited a high agglomeration tendency. Silica sand displayed the most severe agglomeration among all bed materials, even when birch chips with a low silica content was fed at a relatively low temperature. The solid samples of all the bed materials were inspected by light microscopy and Scanning Electron Microscopy (SEM). The Energy Dispersive Spectroscopy (EDS) detector was used to detect the elemental distribution in the surface. The crystal chemical structure was analyzed using X-ray Diffraction (XRD). Magnesite agglomerates glued together by big molten ash particles. There was no coating layer detected on magnesite particles at bed temperatures – below 870 °C. But when the temperature was above 1000 °C, a significant amount of small molten

2. Biomass gasification in the Netherlands

Energy Technology Data Exchange (ETDEWEB)

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

2013-07-15

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

3. Nitrogen compounds in pressurised fluidised bed gasification of biomass and fossil fuels

NARCIS (Netherlands)

De Jong, W.

2005-01-01

Fossil fuels still dominate the energy supply in modern societies. The resources, however, are depleting. Therefore, other energy sources are to be exploited further within this century. Biomass is one of the practically CO2 neutral, renewable contributors to the future energy production. Nowadays

4. Biomass gasification with air in fluidized bed. Hot gas cleanup with selected commercial and full-size nickel-based catalysts

Energy Technology Data Exchange (ETDEWEB)

Caballero, M.A.; Corella, J.; Aznar, M.P.; Gil, J.

2000-05-01

Three selected commercial, full-size steam-reforming catalysts for naphthas, BASF G1-50, ICI 46-1, and Topsoee R-67, are tested at pilot-scale level for hot gas cleanup in biomass gasification in a fluidized bed. Gas composition and tar content in the flue gas are measured before and after the catalytic bed. Variations of the catalytic bed in H{sub 2}, CO, CO{sub 2}, CH{sub 4}, and H{sub 2}O contents are reported for different operating conditions. Tar conversions and an apparent first-order kinetics constant for the overall tar removal reaction are calculated. Tar contents at the exit of the catalytic reactor as low as 10 mg/m{sub n}{sup 3} are obtained in a test of 50 h-on-stream without noticeable catalyst deactivation. Important variations in tar conversion with space time in the catalytic bed, with H{sub 2}O/C* in the flue gas, and with the equivalence ratio in the upstream gasifier are observed. These results obtained at the pilot-scale level and with the use of full-sized commercial catalysts are an important forward step in demonstrating the technical feasibility of the overall biomass gasification process.

5. Gasification of Biomass with CO2 and H2O Mixtures in a Catalytic Fluidised Bed.

Czech Academy of Sciences Publication Activity Database

Jeremiáš, Michal; Pohořelý, Michael; Svoboda, Karel; Manovic, V.; Anthony, E.J.; Skoblia, S.; Beňo, Z.; Šyc, Michal

2017-01-01

Roč. 210, DEC 15 (2017), s. 605-610 ISSN 0016-2361 R&D Projects: GA ČR GC14-09692J Grant - others:NSC(TW) 103-2923-E-042A-001-MY3 Institutional support: RVO:67985858 Keywords : fluidised bed * gas ification * catalyst Subject RIV: JE - Non-nuclear Energetics, Energy Consumption ; Use OBOR OECD: Energy and fuels Impact factor: 4.601, year: 2016

6. Design, fabrication, operation and Aspen simulation of oil shale pyrolysis and biomass gasification process using a moving bed downdraft reactor

Science.gov (United States)

Golpour, Hassan

Energy is the major facilitator of the modern life. Every developed and developing economy requires access to advanced sources of energy to support its growth and prosperity. Declining worldwide crude oil reserves and increasing energy needs has focused attention on developing existing unconventional fossil fuels like oil shale and renewable resources such as biomass. Sustainable, renewable and reliable resources of domestically produced biomass comparing to wind and solar energy is a sensible motivation to establish a small-scale power plant using biomass as feed to supply electricity demand and heat for rural development. The work in Paper I focuses on the possibility of water pollution from spent oil shale which should be studied before any significant commercial production is attempted. In Paper II, the proposed Aspen models for oil shale pyrolysis is to identify the key process parameters for the reactor and optimize the rate of production of syncrude from oil shale. The work in Paper III focuses on (1) Design and operation of a vertical downdraft reactor, (2) Establishing an optimum operating methodology and parameters to maximize syngas production through process testing. Finally in Paper IV, a proposed Aspen model for biomass gasification simulates a real biomass gasification system discussed in Paper III.

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

Energy Technology Data Exchange (ETDEWEB)

Reed, T.B.

1980-09-01

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

8. Biomass utilization for the process of gasification

Directory of Open Access Journals (Sweden)

Josef Spěvák

2008-01-01

Full Text Available Biomass as one of the renewable resources of energy has bright future in utilization, especially in obtaining various forms of energy (heat, electrical energy, gas.According to the conception of energy policy of the Czech Republic and according to the fulfillment of the indicators of renewable resources using until the year 2010, the research of thermophysical characteristics of biofuels was realized.There were acquired considerable amount of results by combustion and gasification process on the basis of three-year project „Biomass energy parameters.” By means of combustion and gasification tests of various (biomass fuels were acquired the results which were not published so far.Acquired results are published in the fuel sheets, which are divided into four parts. They consist of information on fuel composition, ash composition, testing conditions and measurand overview. Measurements were realized for the process of combustion, fluidized-bed gasification and fixed-bed gasification. Following fuels were tested: Acacia, Pine, Birch, Beech, Spruce, Poplar, Willow, Rape, Amaranth, Corn, Flax, Wheat, Safflower, Mallow, and Sorrel.

9. Hydrogen-rich gas production by steam gasification of char from biomass fast pyrolysis in a fixed-bed reactor: influence of temperature and steam on hydrogen yield and syngas composition.

Science.gov (United States)

Yan, Feng; Luo, Si-yi; Hu, Zhi-quan; Xiao, Bo; Cheng, Gong

2010-07-01

Steam gasification experiments of biomass char were carried out in a fixed-bed reactor. The experiments were completed at bed temperature of 600-850 degrees C, a steam flow rate of 0-0.357 g/min/g of biomass char, and a reaction time of 15min. The aim of this study is to determine the effects of bed temperature and steam flow rate on syngas yield and its compositions. The results showed that both high gasification temperature and introduction of proper steam led to higher yield of dry gas and higher carbon conversion efficiency. However, excessive steam reduced gas yield and carbon conversion efficiency. The maximum dry gas yield was obtained at the gasification temperature of 850 degrees C and steam flow rate of 0.165 g/min/g biomass char. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

10. Steam gasification of wood biomass in a fluidized biocatalytic system bed gasifier: A model development and validation using experiment and Boubaker Polynomials Expansion Scheme BPES

Directory of Open Access Journals (Sweden)

Luigi Vecchione

2015-07-01

Full Text Available One of the most important issues in biomass biocatalytic gasification is the correct prediction of gasification products, with particular attention to the Topping Atmosphere Residues (TARs. In this work, performedwithin the European 7FP UNIfHY project, we develops and validate experimentally a model which is able of predicting the outputs,including TARs, of a steam-fluidized bed biomass gasifier. Pine wood was chosen as biomass feedstock: the products obtained in pyrolysis tests are the relevant model input. Hydrodynamics and chemical properties of the reacting system are considered: the hydrodynamic approach is based on the two phase theory of fluidization, meanwhile the chemical model is based on the kinetic equations for the heterogeneous and homogenous reactions. The derived differentials equations for the gasifier at steady state were implemented MATLAB. Solution was consecutively carried out using the Boubaker Polynomials Expansion Scheme by varying steam/biomass ratio (0.5-1 and operating temperature (750-850°C.The comparison between models and experimental results showed that the model is able of predicting gas mole fractions and production rate including most of the representative TARs compounds

11. Leaching From Biomass Gasification Residues

DEFF Research Database (Denmark)

Allegrini, Elisa; Boldrin, Alessio; Polletini, A.

2011-01-01

The aim of the present work is to attain an overall characterization of solid residues from biomass gasification. Besides the determination of chemical and physical properties, the work was focused on the study of leaching behaviour. Compliance and pH-dependence leaching tests coupled with geoche......The aim of the present work is to attain an overall characterization of solid residues from biomass gasification. Besides the determination of chemical and physical properties, the work was focused on the study of leaching behaviour. Compliance and pH-dependence leaching tests coupled...

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

Science.gov (United States)

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

2016-03-01

Chars produced from the pyrolysis of different waste materials have been investigated in terms of their use as a catalyst for the catalytic cracking of biomass pyrolysis gases during the two-stage pyrolysis-gasification of biomass. The chars were produced from the pyrolysis of waste tyres, refused derived fuel and biomass in the form of date stones. The results showed that the hydrocarbon tar yields decreased significantly with all the char materials used in comparison to the non-char catalytic experiments. For example, at a cracking temperature of 800°C, the total product hydrocarbon tar yield decreased by 70% with tyre char, 50% with RDF char and 9% with biomass date stones char compared to that without char. There was a consequent increase in total gas yield. Analysis of the tar composition showed that the content of phenolic compounds decreased and polycyclic aromatic hydrocarbons increased in the product tar at higher char temperatures. Copyright © 2015 Elsevier Ltd. All rights reserved.

13. Biomass Gasification Combined Cycle

Energy Technology Data Exchange (ETDEWEB)

Judith A. Kieffer

2000-07-01

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

14. Biomass gasification with air in a fluidized bed: Effect of the in-bed use of dolomite under different operation conditions

Energy Technology Data Exchange (ETDEWEB)

Gil, J.; Caballero, M.A.; Martin, J.A.; Aznar, M.P.; Corella, J.

1999-11-01

The performance of a biomass gasifier, fluidized-bed type, is improved by in-bed use of calcined dolomite. Tar contents in the raw flue gas below 1 g/m{sub n}{sup 3} are obtained by using a bed with a percentage between 15 and 30 wt% of dolomite (the rest being silica sand). The work is carried out at small pilot-plant scale (10 kg of biomass/h) with equivalence ratios (ER) between 0.20 and 0.35 and temperatures of 800--840 C in the gasifier bed. To replace the eroded and elutriated dolomite (from the gasifier bed), an amount of dolomite (0.40--0.63 mm) is continuously fed, mixed with the biomass at 3 wt%. When the results obtained with in-bed dolomite are compared to the ones gained in a gasifier bed without dolomite, change of the following variables is reported: gas composition and its corresponding heating value, gas and char yields, apparent thermal efficiency, and tar contents. Once the usefulness of the in-bed use of dolomite is established, three main operation variables (ER and temperature of the gasifier bed and freeboard) are studied in the improved gasifier. Carryover of solids from the gasifier also increases when calcined dolomite is used because of its softness. Elutriation rate constants are calculated for several operational parameters.

15. Coal gasification fluidized bed (Winkler gasification) under pressure

International Nuclear Information System (INIS)

Anwer, J.; Boegner, F.

1976-01-01

Due to the 'oil crisis', the gasification of lignite and coal for the production of fuel and synthetic gas has reached increased importance. The present state of the Winkler gasification which has successfully operated for a long time is described. After the basic design of a Winkler gasification plant, the various chemical engineering problems are shown: the design characteristics of a fluidized bed, the reaction kinetics, the dependance of the products on the gasification pressure, and the economics of the process. Finally, the development trend in the USA and the future possibility of heating by nuclear heat is dealt with. (orig.) [de

16. Wood biomass gasification in the world today

International Nuclear Information System (INIS)

Nikolikj, Ognjen; Perishikj, Radovan; Mikulikj, Jurica

1999-01-01

Today gasification technology of different kinds represents a more and more interesting option of the production of energy forms. The article describes a biomass gasification plant (waste wood) Sydkraft, Vernamo from Sweden. (Author)

17. Biomass gasification in fluidized bed at pilot-scale with steam-oxygen mixtures. Product distribution for very different operating conditions

Energy Technology Data Exchange (ETDEWEB)

Gil, J.; Aznar, M.P.; Caballero, M.A.; Frances, E.; Corella, J. [University of Zaragoza, Zaragoza (Spain). Chemical and Environmental Engineering Dept.

1997-11-01

Biomass gasification in a fluidized bed with steam-O{sub 2} mixtures has been studied in detail at pilot plant scale. The gasifier used was 15 cm i.d. and 3.2 m high, and it was fed with pine wood chips at flow rates of 5-20 kg/h. Main operating variables studied were gasifier bed temperature (780-890{degree}C), steam to oxygen in the feeding ratio (2-3 mol/mol), and gasifying agent (H{sub 2}O + O{sub 2}) to biomass feed ratio (0.6-1.6 kg/kg daf). Product distribution here shown includes gas, tar and char yields, gas composition (H{sub 2}, CO, CO{sub 2}, CH{sub 4} steam,...) and heating value, tar composition and content in the flue gas, gas heating value, apparent thermal efficiency, etc. Under good operating conditions the following gas is obtained: tar content of 5 g/Nm{sup 3}, 30 vol % H{sub 2}, heating value of 16.0 MJ/Nm{sub 3} (dry basis), gas yield of 1.2 Nm{sup 3} (dry basis)/kg biomass fed. 28 refs., 29 figs., 1 tab.

18. Biomass gasification with steam in fluidized bed: Effectiveness of CaO, MgO, and CaO-MgO for hot raw gas cleaning

Energy Technology Data Exchange (ETDEWEB)

Delgado, J.; Aznar, M.P. [Univ. of Saragossa (Spain). Dept. of Chemical and Environmental Engineering; Corella, J. [Univ. Complutense of Madrid (Spain). Dept. of Chemical Engineering

1997-05-01

The upgrading of the raw hot gas from a bubbling fluidized bed biomass gasifier is studied using cheap calcined minerals or rocks downstream from the gasifier. Biomass gasification is made with steam (not air) at 750--780 C and about 0.5--1.0 kg of biomass/h. Calcined solids used are dolomite (MgO-CaO), pure calcite (CaO), and pure magnesite (MgO). Variables studied have been temperature of the secondary bed (780--910 C), time of contact or space-time of the gas (0.08--0.32 kg{center_dot}h/m{sup 3}n), and particle diameter (1--4 mm) and type of mineral. Their effects on tar conversion, tar amount in the exit gas, product distribution, and gas composition are presented. Using a macrokinetic model for the tar disappearance network, the activities of the stones are expressed by their apparent kinetic constant. Apparent energies of activation for tar elimination (42--47 kJ/mol) and preexponential and effectiveness factors are given for all tested solids of which the most active is the calcined dolomite.

19. Fluidised-bed combustion of gasification residue

Energy Technology Data Exchange (ETDEWEB)

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

1996-12-01

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

20. Plasma Treatments and Biomass Gasification

Science.gov (United States)

Luche, J.; Falcoz, Q.; Bastien, T.; Leninger, J. P.; Arabi, K.; Aubry, O.; Khacef, A.; Cormier, J. M.; Lédé, J.

2012-02-01

Exploitation of forest resources for energy production includes various methods of biomass processing. Gasification is one of the ways to recover energy from biomass. Syngas produced from biomass can be used to power internal combustion engines or, after purification, to supply fuel cells. Recent studies have shown the potential to improve conventional biomass processing by coupling a plasma reactor to a pyrolysis cyclone reactor. The role of the plasma is twofold: it acts as a purification stage by reducing production of tars and aerosols, and simultaneously produces a rich hydrogen syngas. In a first part of the paper we present results obtained from plasma treatment of pyrolysis oils. The outlet gas composition is given for various types of oils obtained at different experimental conditions with a pyrolysis reactor. Given the complexity of the mixtures from processing of biomass, we present a study with methanol considered as a model molecule. This experimental method allows a first modeling approach based on a combustion kinetic model suitable to validate the coupling of plasma with conventional biomass process. The second part of the paper is summarizing results obtained through a plasma-pyrolysis reactor arrangement. The goal is to show the feasibility of this plasma-pyrolysis coupling and emphasize more fundamental studies to understand the role of the plasma in the biomass treatment processes.

1. Studies on biomass char gasification and dynamics

Science.gov (United States)

You, Zhanping; You, Shijun; Ma, Xiaoyan

2018-01-01

The gasification performances of two kinds of biomass char by experiment methods are studied, including conversion rate and gasification gas component with temperature and time. Experimental results show that gasification temperature has important effects on the conversion rate and gas component. In the range of experimental temperature, char conversion rates are no more than 30.0%. The apparent activation energies and apparent reaction frequency factors of two biomass chars are obtained through kinetic studies.

2. Co-gasification of biomass and plastics: pyrolysis kinetics studies, experiments on 100 kW dual fluidized bed pilot plant and development of thermodynamic equilibrium model and balances.

Science.gov (United States)

Narobe, M; Golob, J; Klinar, D; Francetič, V; Likozar, B

2014-06-01

Thermo-gravimetric analysis (TGA) of volatilization reaction kinetics for 50 wt.% mixtures of plastics (PE) and biomass (wood pellets) as well as for 100 wt.% plastics was conducted to predict decomposition times at 850°C and 900°C using iso-conversional model method. For mixtures, agreement with residence time of dual fluidized bed (DFB) reactor, treated as continuous stirred-tank reactor (CSTR), was obtained at large conversions. Mono-gasification of plastics and its co-gasification with biomass were performed in DFB pilot plant, using olivine as heterogeneous catalyst and heat transfer agent. It was found that co-gasification led to successful thermochemical conversion of plastics as opposed to mono-gasification. Unknown flow rates were determined applying nonlinear regression to energy and mass balances acknowledging combustion fuel, air, steam, feedstock, but also exiting char, tar, steam and other components in DFB gasification unit. Water-gas shift equilibrium and methanol synthesis requirements were incorporated into gasification model, based on measurements. Copyright © 2014 Elsevier Ltd. All rights reserved.

3. Modeling integrated biomass gasification business concepts

Science.gov (United States)

Peter J. Ince; Ted Bilek; Mark A. Dietenberger

2011-01-01

Biomass gasification is an approach to producing energy and/or biofuels that could be integrated into existing forest product production facilities, particularly at pulp mills. Existing process heat and power loads tend to favor integration at existing pulp mills. This paper describes a generic modeling system for evaluating integrated biomass gasification business...

4. 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.

5. Hydrogen production from biomass over steam gasification

Energy Technology Data Exchange (ETDEWEB)

Rauch, R.; Potetz, A.; Hofbauer, H. [Vienna Univ. of Technology (Austria). Inst. of Chemical Engineering; Weber, G. [Bioenergy 2020+, Guessing (Austria)

2010-12-30

Renewable hydrogen is one option for a clean energy carrier in the future. There were several research programs in the past, to produce hydrogen on a renewable basis by electrolysis, direct conversion of water or by gasification of biomass. None of these options were developed to a stage, that they could be used on a commercial basis. At the moment almost all hydrogen is produced from fossil fuels and one main consumer of hydrogen are refineries. So a good option to demonstrate the production of renewable hydrogen and bring it later into the market is over refineries. The most economic option to produce renewable hydrogen at the moment is over gasification of biomass. In Austria an indirect gasification system was developed and is demonstrated in Guessing, Austria. The biomass CHP Guessing uses the allothermal steam dual fluidised bed gasifier and produces a high grade product gas, which is used at the moment for the CHP in a gas engine. As there is no nitrogen in the product gas and high hydrogen content, this gas can be also used as synthesis gas or for production of hydrogen. The main aim of this paper is to present the experimental and simulation work to convert biomass into renewable hydrogen. The product gas of the indirect gasification system is mainly hydrogen, carbon monoxide, carbon dioxide and methane. Within the ERA-Net project ''OptiBtLGas'' the reforming of methane and the CO-shift reaction was investigated to convert all hydrocarbons and carbon monoxide to hydrogen. On basis of the experimental results the mass- and energy balances of a commercial 100 MW fuel input plant was done. Here 3 different cases of complexity of the overall plant were simulated. The first case was without reforming and CO-shift, only by hydrogen separation. The second case was by including steam - reforming and afterwards separation of hydrogen. The third case includes hydrocarbon reforming, CO-shift and hydrogen separation. In all cases the off-gases (CO

6. 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...

7. Biomass gasification for production of 'green energy'

International Nuclear Information System (INIS)

Mambre, V.

2008-01-01

This paper presents the differences between biomass gasification and biomass methanation, two ways of using biomass for decentralized production of energy. The stakes of biomass and biomass gasification for meeting the European and national energy goals and environmental targets are summarized. The gasification principle is described and in particular the FICFB optimized process from Repotec for the production of concentrated syngas. The four different ways of syngas valorization (combined heat and power (CHP), 'green methane' (SNG), 'green hydrogen' (gas shift) and liquid biofuels of 2. generation (Fisher-Tropsch)) are recalled and compared with each other. Finally, the economical and environmental key issues of the global chain are summarized with their technological and scientific key locks. The GAYA R and D project of Gaz de France Suez group, which aims at developing gasification and methanation demonstration plants through different programs with European partners, is briefly presented. (J.S.)

8. On a clean power generation system with the co-gasification of biomass and coal in a quadruple fluidized bed gasifier.

Science.gov (United States)

Yan, Linbo; He, Boshu

2017-07-01

A clean power generation system was built based on the steam co-gasification of biomass and coal in a quadruple fluidized bed gasifier. The chemical looping with oxygen uncoupling technology was used to supply oxygen for the calciner. The solid oxide fuel cell and the steam turbine were combined to generate power. The calcium looping and mineral carbonation were used for CO 2 capture and sequestration. The aim of this work was to study the characteristics of this system. The effects of key operation parameters on the system total energy efficiency (ŋ ten ), total exergy efficiency (ŋ tex ) and carbon sequestration rate (R cs ) were detected. The energy and exergy balance calculations were implemented and the corresponding Sankey and Grassmann diagrams were drawn. It was found that the maximum energy and exergy losses occurred in the steam turbine. The system ŋ ten and ŋ tex could be ∼50% and ∼47%, and R cs could be over unit. Copyright © 2017 Elsevier Ltd. All rights reserved.

9. Application and Discussion of Dual Fluidized Bed Reactor in Biomass Energy Utilization

Science.gov (United States)

Guan, Haibin; Fan, Xiaoxu; Zhao, Baofeng; Yang, Liguo; Sun, Rongfeng

2018-01-01

As an important clean and renewable energy, biomass has a broad market prospect. The dual fluidized bed is widely used in biomass gasification technology, and has become an important way of biomass high-value utilization. This paper describes the basic principle of dual fluidized bed gasification, from the gas composition, tar content and thermal efficiency of the system point of view, analyzes and summarizes several typical dual fluidized bed biomass gasification technologies, points out the existence of gas mixing, the external heat source, catalyst development problems on gas. Finally, it is clear that the gasification of biomass in dual fluidized bed is of great industrial application and development prospect.

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

Energy Technology Data Exchange (ETDEWEB)

Reed, T.B. (comp.)

1979-07-01

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

11. The study of reactions influencing the biomass steam gasification process

Energy Technology Data Exchange (ETDEWEB)

C. Franco; F. Pinto; I. Gulyurtlu; I. Cabrita [INETI-DEECA, Lisbon (Portugal)

2003-05-01

Steam gasification studies were carried out in an atmospheric fluidised bed. The gasifier was operated over a temperature range of 700 900{sup o}C whilst varying a steam/biomass ratio from 0.4 to 0.85 w/w. Three types of forestry biomass were studied: Pinus pinaster (softwood), Eucalyptus globulus and holm-oak (hardwood). The energy conversion, gas composition, higher heating value and gas yields were determined and correlated with temperature, steam/biomass ratio, and species of biomass used. The results obtained seemed to suggest that the operating conditions were optimised for a gasification temperature around 830{sup o}C and a steam/biomass ratio of 0.6 0.7 w/w, because a gas richer in hydrogen and poorer in hydrocarbons and tars was produced. These conditions also favoured greater energy and carbon conversions, as well the gas yield. The main objective of the present work was to determine what reactions were dominant within the operation limits of experimental parameters studied and what was the effect of biomass type on the gasification process. As biomass wastes usually have a problem of availability because of seasonal variations, this work analysed the possibility of replacing one biomass species by another, without altering the gas quality obtained. 19 refs., 8 figs. 2 tabs.

12. 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.

13. Synergistic combination of biomass torrefaction and co-gasification: Reactivity studies.

Science.gov (United States)

Zhang, Yan; Geng, Ping; Liu, Rui

2017-12-01

Two typical biomass feedstocks obtained from woody wastes and agricultural residues were torrefied or mildly pyrolized in a fixed-bed reactor. Effects of the torrefaction conditions on product distributions, compositional and energetic properties of the solid products, char gasification reactivity, and co-gasification behavior between coal and torrefied solids were systematically investigated. Torrefaction pretreatment produced high quality bio-solids with not only increased energy density, but also concentrated alkali and alkaline earth metals (AAEM). As a consequence of greater retention of catalytic elements in the solid products, the chars derived from torrefied biomass exhibited a faster conversion than those derived from raw biomass during CO 2 gasification. Furthermore, co-gasification of coal/torrefied biomass blends exhibited stronger synergy compared to the coal/raw biomass blends. The results and insights provided by this study filled a gap in understanding synergy during co-gasification of coal and torrefied biomass. Copyright © 2017 Elsevier Ltd. All rights reserved.

14. Fluidized bed combustion and gasification of corncobs

Energy Technology Data Exchange (ETDEWEB)

Butuk, N.; Morey, R.V.

1987-01-01

A 15.2 cm (6 in) diameter fluidized bed reactor was evaluated in combustion and gasification modes using hammer milled corncobs with average particle size of 0.2 cm (0.08 in). Combustion tests were run at 10 and 32% w.b. moisture contents and 710 degrees C and 815 degrees C bed temperatures. Heat output rates of 13.4 to 16.2 MJ/h were achieved. Gasification tests were run at 10 and 22% w.b. moisture contents and 710 degrees C bed temperature, and heat output rates of 84 to 133 MJ/h were achieved. Particulates in the exhaust gases were determined in both the combustion and gasification modes of operation. The measurements showed the inadequacy of the flame holder for flaring the gas in the gasification mode. A combustion model based on elemental balances and the first law of thermodynamics was developed and compared to experimental results. The model adequately predicted fuel-air ratios and exhaust gas mass fractions in the combustion mode.

15. Catalytic gasification of dry and wet biomass

NARCIS (Netherlands)

van Rossum, G.; Potic, B.; Kersten, Sascha R.A.; van Swaaij, Willibrordus Petrus Maria

2009-01-01

Catalytic gasification of dry biomass and of wet biomass streams in hot compressed water are reviewed and discussed as potential technologies for the production of synthesis gas, hydrogen- and methane-rich gas. Next to literature data also new experimental results from our laboratory on catalytic

16. Guideline for safe and eco-friendly biomass gasification

Energy Technology Data Exchange (ETDEWEB)

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

2009-11-15

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

17. Fluidised bed gasification of low grade South African coals

CSIR Research Space (South Africa)

North, BC

2006-09-01

Full Text Available -going investigation into one potential Clean Coal Technology (CCT), namely fluidised bed gasification. Coal gasification holds the potential benefits of increased efficiency, reduced water consumption and co-production of liquid and gaseous fuels and chemicals...

18. Bio-syngas production from biomass catalytic gasification

International Nuclear Information System (INIS)

Lv, Pengmei; Yuan, Zhenhong; Wu, Chuangzhi; Ma, Longlong; Chen, Yong; Tsubaki, Noritatsu

2007-01-01

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 H 2 /CO is an important factor that affects the performance of this process. In this study, the characteristics of biomass gasification gas, such as H 2 /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 H 2 content reaches 52.47 vol%, while the ratio of H 2 /CO varies between 1.87 and 4.45. The results indicate that an appropriate temperature (750 o C for the current study) and more catalyst are favorable for getting a higher H 2 /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

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

Science.gov (United States)

McCaffrey, Zach

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

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

Energy Technology Data Exchange (ETDEWEB)

Francis Lau

2002-12-01

general term, and includes heating as well as the injection of other ''ingredients'' such as oxygen and water. Pyrolysis alone is a useful first step in creating vapors from coal or biomass that can then be processed in subsequent steps to make liquid fuels. Such products are not the objective of this project. Therefore pyrolysis was not included in the process design or in the economic analysis. High-pressure, fluidized bed gasification is best known to GTI through 30 years of experience. Entrained flow, in contrast to fluidized bed, is a gasification technology applied at much larger unit sizes than employed here. Coal gasification and residual oil gasifiers in refineries are the places where such designs have found application, at sizes on the order of 5 to 10 times larger than what has been determined for this study. Atmospheric pressure gasification is also not discussed. Atmospheric gasification has been the choice of all power system pilot plants built for biomass to date, except for the Varnamo plant in Sweden, which used the Ahlstrom (now Foster Wheeler) pressurized gasifier. However, for fuel production, the disadvantage of the large volumetric flows at low pressure leads to the pressurized gasifier being more economical.

1. Biomass gasification hot gas cleanup for power generation

Energy Technology Data Exchange (ETDEWEB)

Wiant, B.C.; Bachovchin, D.M. [Westinghouse Electric Corp., Orlando, FL (United States); Carty, R.H.; Onischak, M. [Institute of Gas Technology, Chicago, IL (United States); Horazak, D.A. [Gilbert/Commonwealth, Reading, PA (United States); Ruel, R.H. [The Pacific International Center for High Technology Research, Honolulu, HI (United States)

1993-12-31

In support of the US Department of Energy`s Biomass Power Program, a Westinghouse Electric led team consisting of the Institute of Gas Technology (IGT), Gilbert/Commonwealth (G/C), and the Pacific International Center for High Technology Research (PICHTR), is conducting a 30 month research and development program. The program will provide validation of hot gas cleanup technology with a pressurized fluidized bed, air-blown, biomass gasifier for operation of a gas turbine. This paper discusses the gasification and hot gas cleanup processes, scope of work and approach, and the program`s status.

2. Chemicals Derived from Biomass Thermolysis and Gasification

Energy Technology Data Exchange (ETDEWEB)

Schaidle, Joshua A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Talmadge, Michael S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Biddy, Mary J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Nimlos, Mark R [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Bratis, Adam D [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-07-14

The United States has the potential to sustainably produce over 1 billion dry tons of nonfood biomass per year by 2030. While conversion of this biomass into fuels has garnished significant attention, these renewable feedstocks can also be converted into valuable chemicals. Analogous to petroleum refining, the coproduction of fuels and chemicals from biomass enables more complete utilization of the feedstock and supports the growth of a bio-economy by improving biorefinery economics. This chapter provides an overview of biomass thermolysis and gasification technologies, highlights existing and future chemical production opportunities, and elaborates on specific challenges associated with product separation and purification.

3. Hydrogen-rich syngas production and tar removal from biomass gasification using sacrificial tyre pyrolysis char

OpenAIRE

Al-Rahbi, AS; Williams, PT

2017-01-01

Carbonaceous materials have been proven to have a high catalytic activity for tar removal from the syngas produced from biomass gasification. The simultaneous reforming and gasification of pyrolysis gases and char could have a significant role in increasing the gas yield and decreasing the tar in the product syngas. This study investigates the use of tyre char as a catalyst for H2-rich syngas production and tar reduction during the pyrolysis-reforming of biomass using a two stage fixed bed re...

4. Catalytic gasification of biomass (Miscanthus) enhanced by CO2 sorption.

Science.gov (United States)

Zamboni, I; Debal, M; Matt, M; Girods, P; Kiennemann, A; Rogaume, Y; Courson, C

2016-11-01

The main objective of this work concerns the coupling of biomass gasification reaction and CO 2 sorption. The study shows the feasibility to promote biomass steam gasification in a dense fluidized bed reactor with CO 2 sorption to enhance tar removal and hydrogen production. It also proves the efficiency of CaO-Ca 12 Al 14 O 33 /olivine bi-functional materials to reduce heavy tar production. Experiments have been carried out in a fluidized bed gasifier using steam as the fluidizing medium to improve hydrogen production. Bed materials consisting of CaO-based oxide for CO 2 sorption (CaO-Ca 12 Al 14 O 33 ) deposited on olivine for tar reduction were synthesized, their structural and textural properties were characterized by Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD), and temperature-programmed reduction (TPR) methods, and the determination of their sorption capacity and stability analyzed by thermogravimetric analysis (TGA). It appears that this CaO-Ca 12 Al 14 O 33 /olivine sorbent/catalyst presents a good CO 2 sorption stability (for seven cycles of carbonation/decarbonation). Compared to olivine and Fe/olivine in a fixed bed reactor for steam reforming of toluene chosen as tar model compound, it shows a better hydrogen production rate and a lower CO 2 selectivity due to its sorption on the CaO phase. In the biomass steam gasification, the use of CaO-Ca 12 Al 14 O 33 /olivine as bed material at 700 °C leads to a higher H 2 production than olivine at 800 °C thanks to CO 2 sorption. Similar tar concentration and lighter tar production (analyzed by HPLC/UV) are observed. At 700 °C, sorbent addition allows to halve tar content and to eliminate the heaviest tars.

5. Gasification of wood in a fluidized bed reactor

Energy Technology Data Exchange (ETDEWEB)

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

1997-06-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

1998-09-01

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

7. Experimental investigations of biomass gasification with carbon-dioxide

Science.gov (United States)

Sircar, Indraneel

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

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

Energy Technology Data Exchange (ETDEWEB)

2009-10-15

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2009-07-01

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

10. Feasibility of Biomass Biodrying for Gasification Process

Science.gov (United States)

Hamidian, Arash

An important challenge of biomass gasification is the limitation of feedstock quality especially the moisture content, which plays a significant role on the performance of gasification process. Gasification requires low moisture levels (20% and less) and several reports have emphasized on the moisture as a typical problem while gasifying biomass. Moisture affects overall reaction rates in the gasifiers as a result of temperature drop and ultimately increases tar content, decreases gas yield, changes the composition of produced gas and affects the efficiency. Therefore, it is mandatory to pre-treat the biomass before gasification and reduce the moisture content to the suitable and economic level. The well-known solutions are either natural drying (not practical for commercial plants) or conventional drying technologies (have high operating costs). Biodrying is an alternative process, which uses both convective air and heat of biological reactions as a source of energy, to reduce the moisture. In the biodrying reactor heat is generated from exothermic decomposition of organic fraction of biomass and that is why the process is called "self-heating process". Employing such technology for drying biomass at pre-treatment units of gasification process returns several economic and environmental advantages to mills. In Europe, municipal waste treatment (MSW) plants use the biodrying at commercial scale to degrade a part of the biodegradable fraction of waste to generate heat and reduce the moisture content for high quality SRF (Solid Recovered Fuel) production. In Italy, wine industry is seeking to develop biodrying for energy recovery of grape wastes after fermentation and distillation, which returns economic benefits to the industry. In Canada, the development of biodrying technology for pulp and paper industry was started at Ecole polytechnique de Montreal as an option for sludge management solution. Therefore, batch biodrying reactor was successfully developed in 2004

11. The carbon dioxide gasification characteristics of biomass char samples and their effect on coal gasification reactivity during co-gasification.

Science.gov (United States)

Mafu, Lihle D; Neomagus, Hein W J P; Everson, Raymond C; Okolo, Gregory N; Strydom, Christien A; Bunt, John R

2017-12-18

The carbon dioxide gasification characteristics of three biomass char samples and bituminous coal char were investigated in a thermogravimetric analyser in the temperature range of 850-950 °C. Char SB exhibited higher reactivities (R i , R s , R f ) than chars SW and HW. Coal char gasification reactivities were observed to be lower than those of the three biomass chars. Correlations between the char reactivities and char characteristics were highlighted. The addition of 10% biomass had no significant impact on the coal char gasification reactivity. However, 20 and 30% biomass additions resulted in increased coal char gasification rate. During co-gasification, chars HW and SW caused increased coal char gasification reactivity at lower conversions, while char SB resulted in increased gasification rates throughout the entire conversion range. Experimental data from biomass char gasification and biomass-coal char co-gasification were well described by the MRPM, while coal char gasification was better described by the RPM. Copyright © 2018 Elsevier Ltd. All rights reserved.

12. Hydrogen production from algal biomass via steam gasification.

Science.gov (United States)

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

2014-08-01

Algal biomasses were tested as feedstock for steam gasification in a dual-bed microreactor in a two-stage process. Gasification experiments were carried out in absence and presence of catalyst. The catalysts used were 10% Fe₂O₃-90% CeO₂ and red mud (activated and natural forms). Effects of catalysts on tar formation and gasification efficiencies were comparatively investigated. It was observed that the characteristic of algae gasification was dependent on its components and the catalysts used. The main role of the catalyst was reforming of the tar derived from algae pyrolysis, besides enhancing water gas shift reaction. The tar reduction levels were in the range of 80-100% for seaweeds and of 53-70% for microalgae. Fe₂O₃-CeO₂ was found to be the most effective catalyst. The maximum hydrogen yields obtained were 1036 cc/g algae for Fucus serratus, 937 cc/g algae for Laminaria digitata and 413 cc/g algae for Nannochloropsis oculata. Copyright © 2014 Elsevier Ltd. All rights reserved.

13. Co-gasification of sewage sludge and woody biomass in a fixed-bed downdraft gasifier: toxicity assessment of solid residues.

Science.gov (United States)

Rong, Le; Maneerung, Thawatchai; Ng, Jingwen Charmaine; Neoh, Koon Gee; Bay, Boon Huat; Tong, Yen Wah; Dai, Yanjun; Wang, Chi-Hwa

2015-02-01

As the demand for fossil fuels and biofuels increases, the volume of ash generated will correspondingly increase. Even though ash disposal is now strictly regulated in many countries, the increasing volume of ash puts pressure on landfill sites with regard to cost, capacity and maintenance. In addition, the probability of environmental pollution from leakage of bottom ash leachate also increases. The main aim of this research is to investigate the toxicity of bottom ash, which is an unavoidable solid residue arising from biomass gasification, on human cells in vitro. Two human cell lines i.e. HepG2 (liver cell) and MRC-5 (lung fibroblast) were used to study the toxicity of the bottom ash as the toxins in the bottom ash may enter blood circulation by drinking the contaminated water or eating the food grown in bottom ash-contaminated water/soil and the toxic compounds may be carried all over the human body including to important organs such as lung, liver, kidney, and heart. It was found that the bottom ash extract has a high basicity (pH = 9.8-12.2) and a high ionic strength, due to the presence of alkali and alkaline earth metals e.g. K, Na, Ca and Mg. Moreover, it also contains concentrations of heavy metals (e.g. Zn, Co, Cu, Fe, Mn, Ni and Mo) and non-toxic organic compounds. Although human beings require these trace elements, excessive levels can be damaging to the body. From the analyses of cell viability (using MTS assay) and morphology (using fluorescence microscope), the high toxicity of the gasification bottom ash extract could be related to effects of high ionic strength, heavy metals or a combination of these two effects. Therefore, our results suggest that the improper disposal of the bottom ash wastes arising from gasification can create potential risks to human health and, thus, it has become a matter of urgency to find alternative options for the disposal of bottom ash wastes. Copyright © 2014 Elsevier Ltd. All rights reserved.

14. Fixed-bed gasification research using US coals. Volume 10. Gasification of Benton lignite

Energy Technology Data Exchange (ETDEWEB)

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

1985-05-01

A single-staged, fixed-bed Wellman-Galusha gasifier coupled with a hot, raw gas combustion system and scrubber has been used to gasify numerous coals from throughout the United States. The gasification test program is organized as a cooperative effort by private industrial participants and governmental agencies. The consortium of participants is organized under the Mining and Industrial Fuel Gas (MIFGa) Group. This report is the tenth volume in a series of reports describing the atmospheric pressure, fixed-bed gasification of US coals. This specific report describes the gasification of Benton lignite. The period of gasification test was November 1-8, 1983. 16 refs., 22 figs., 19 tabs.

15. Allothermal gasification of biomass using micron size biomass as external heat source.

Science.gov (United States)

Cheng, Gong; Li, Qian; Qi, Fangjie; Xiao, Bo; Liu, Shiming; Hu, Zhiquan; He, Piwen

2012-03-01

An allothermal biomass gasification system using biomass micron fuel (BMF) as external heat source was developed. In this system, heat supplied to gasifier was generated from combustion of BMF. Biomass feedstock was gasified with steam and then tar in the produced gas was decomposed in a catalytic bed with NiO/γ-Al(2)O(3) catalyst. Finally the production gas was employed as a substitute for civil fuel gas. An overall energy analysis of the system was also investigated. The results showed that the lower heating value of the product gas reached more than 12 MJ/Nm(3). The combusted BMF accounted for 26.8% of the total energy input. Allothermal gasification based on the substituted BMF for conventional energy was an efficient and economical technology to obtain bioenergy. Copyright © 2011 Elsevier Ltd. All rights reserved.

16. Wood biomass gasification: Technology assessment and prospects in developing countries

International Nuclear Information System (INIS)

1992-05-01

This investigation of the technical-economic feasibility of the development and use of wood biomass gasification plants to help meet the energy requirements of developing countries covers the following aspects: resource availability and production; gasification technologies and biomass gasification plant typology; plant operating, maintenance and safety requirements; the use of the biomass derived gas in internal combustion engines and boilers; and the nature of energy requirements in developing countries. The paper concludes with a progress report on biomass gasification research programs being carried out in developing countries world-wide

17. Reaction Mechanism of Tar Evolution in Biomass Steam Gasification for Hydrogen Production

International Nuclear Information System (INIS)

Shingo Katayama; Masahiro Suzuki; Atsushi Tsutsumi

2006-01-01

Reaction mechanism of tar evolution in steam gasification of biomass was investigated with a continuous cross-flow moving bed type differential reactor, in which tar and gases can be fractionated according to reaction time. We estimated that time profile of tar and gas evolution in the gasification of cellulose, xylan, and lignin, and compared it with experimental product time profile of real biomass gasification. The experimental tar evolution rate is different from estimated tar evolution rate. The estimated tar evolution rate has a peak at 20 s. On the other hand, the experimental tar evolution rate at 20 s is little, and tar at initial stage includes more water-soluble and water-insoluble compounds. It can be concluded that in the real biomass steam gasification the evolution of tar from cellulose and lignin component was found to be precipitated by that from hemi-cellulose component. (authors)

18. Catalytic gasification of oil-extracted residue biomass of Botryococcus braunii.

Science.gov (United States)

Watanabe, Hideo; Li, Dalin; Nakagawa, Yoshinao; Tomishige, Keiichi; Watanabe, Makoto M

2015-09-01

Catalytic gasification of the oil-extracted residue biomass of Botryococcus braunii was demonstrated in a laboratory-scale continuous feeding dual bed reactor. Steam gasification at 1023 K over Ni-Fe/Mg/Al catalyst can completely reform tar derived from pyrolysis of the residue biomass into C1 gases and hydrogen, and has achieved 91%-C conversion to gaseous product (CO+CO2+CH4). Composition of product gas has higher contents of CO and H2 with their ratio (H2/CO) of around 2.4 which is slightly H2-rich syngas. Maximum hydrogen yield of 74.7 mmol g-biomass(-1) obtained in this work is much higher than that from gasification of other algal biomass reported in literature. The residue biomass of B. braunii can be a superior renewable source of syngas or hydrogen. Copyright © 2015 Elsevier Ltd. All rights reserved.

19. 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

20. Fluidized bed gasification of select granular biomaterials.

Science.gov (United States)

Subramanian, P; Sampathrajan, A; Venkatachalam, P

2011-01-01

Biomaterials can be converted into solid, liquid and gaseous fuels through thermochemical or biochemical conversion processes. Thermochemical conversion of granular biomaterials is difficult because of its physical nature and one of the suitable processes is fluidized bed gasification. In this study, coir pith, rice husk and saw dust were selected and synthetic gas was generated using a fluidized bed gasifier. Gas compositions of product gas were analyzed and the percentage of carbon monoxide and carbon dioxide was in the range of 8.24-19.55 and 10.21-17.14, respectively. The effect of equivalence ratio (0.3, 0.4 and 0.5) and reaction time (at 10 min interval) on gas constituents was studied. The gas yield for coir pith, rice husk and sawdust were found to be in the range of 1.98-3.24, 1.79-2.81 and 2.18-3.70 Nm3 kg(-1), respectively. Models were developed to study the influence of biomaterial properties and operating conditions on molar concentration of gas constituents and energy output. Copyright Â© 2010 Elsevier Ltd. All rights reserved.

1. Gasification of rice husk in a fluidized bed reactor

Energy Technology Data Exchange (ETDEWEB)

Mansaray, K.G.

1998-12-31

The development of two mathematical models which simulate the performance of a dual distributor fluidized bed gasifier was described. The gasification of rice husks in the gasifier using air as the sole gasifying agent was investigated. The four stages of the study were: (1) modification of the existing fluidized bed gasifier and data acquisition system, (2) preliminary experimentation to assess the suitability of rice husks for gasification to determine the feasible range of operating conditions for fluidized bed gasification of rice husks and to obtain data for proper design of thermochemical conversion systems, (3) development of mathematical models to predict the performance of the fluidized bed gasification system, and (4) experimentation to investigate the effects of various operating variables on the performance of the gasifier and provide data to evaluate the validity of the models.

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

International Nuclear Information System (INIS)

Wilen, C.; Kurkela, E.

1997-01-01

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 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 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 the main

3. 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

4. Nordic seminar on biomass gasification and combustion

International Nuclear Information System (INIS)

1993-01-01

The report comprises a collection of papers from a seminar arranged as a part of the Nordic Energy Research Program. The aim of this program is to strengthen the basic competence in the energy field at universities and research organizations in the Nordic countries. In the program 1991-1994 six areas are selected for cooperation such as energy and society, solid fuels, district heating, petroleum technology, bioenergy and environment, and fuel cells. The topics deal both with biomass combustion and gasification, and combustion of municipal solid waste (MSW) and refuse derived fuel (RDF). A number of 11 papers are prepared. 97 refs., 91 figs., 11 tabs

5. Nordic seminar on biomass gasification and combustion

Energy Technology Data Exchange (ETDEWEB)

NONE

1993-12-31

The report comprises a collection of papers from a seminar arranged as a part of the Nordic Energy Research Program. The aim of this program is to strengthen the basic competence in the energy field at universities and research organizations in the Nordic countries. In the program 1991-1994 six areas are selected for cooperation such as energy and society, solid fuels, district heating, petroleum technology, bioenergy and environment, and fuel cells. The topics deal both with biomass combustion and gasification, and combustion of municipal solid waste (MSW) and refuse derived fuel (RDF). A number of 11 papers are prepared. 97 refs., 91 figs., 11 tabs.

6. 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.

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

Energy Technology Data Exchange (ETDEWEB)

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

2013-09-01

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

8. Development of biomass gasification systems for gas turbine power generation

International Nuclear Information System (INIS)

Larson, E.D.; Svenningsson, P.

1991-01-01

Gas turbines are of interest for biomass applications because, unlike steam turbines, they have relatively high efficiencies and low unit capital costs in the small sizes appropriate for biomass installations. Gasification is a simple and efficient way to make biomass usable in gas turbines. The authors evaluate here the technical requirements for gas turbine power generation with biomass gas and the status of pressurized biomass gasification and hot gas cleanup systems. They also discuss the economics of gasifier-gas turbine cycles and make some comparisons with competing technologies. Their analysis indicates that biomass gasifiers fueling advanced gas turbines are promising for cost-competitive cogeneration and central station power generation. Gasifier-gas turbine systems are not available commercially, but could probably be developed in 3 to 5 years. Extensive past work related to coal gasification and pressurized combustion of solid fuels for gas turbines would be relevant in this effort, as would work on pressurized biomass gasification for methanol synthesis

9. Fixed-bed gasification research using US coals. Volume 13. Gasification of Blind Canyon bituminous coal

Energy Technology Data Exchange (ETDEWEB)

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

1985-05-01

A single-staged, fixed-bed Wellman-Galusha gasifier coupled with a hot, raw gas combustion system and scrubber has been used to gasify numerous coals from throughout the United States. The gasification test program is organized as a cooperative effort by private industrial participants and governmental agencies. The consortium of participants is organized under the Mining and Industrial Fuel Gas (MIFGa) Group. This report is the thirteenth volume in a series of reports describing the atmospheric pressure, fixed-bed gasification of US coals. This specific report describes the gasification of Blind Canyon bituminous coal, from July 31, 1984 to August 11, 1984. 6 refs., 22 figs., 20 tabs.

10. Green Gasification Technology for Wet Biomass

Directory of Open Access Journals (Sweden)

W. H. Chong

2010-12-01

Full Text Available The world now is facing two energy related threats which are lack of sustainable, secure and affordable energy supplies and the environmental damage acquired in producing and consuming ever-increasing amount of energy. In the first decade of the twenty-first century, increasing energy prices reminds us that an affordable energy plays an important role in economic growth and human development. To overcome the abovementioned problem, we cannot continue much longer to consume finite reserves of fossil fuels, the use of which contributes to global warming. Preferably, the world should move towards more sustainable energy sources such as wind energy, solar energy and biomass. However, the abovementioned challenges may not be met solely by introduction of sustainable energy forms. We also need to use energy more efficiently. Developing and introducing more efficient energy conversion technologies is therefore important, for fossil fuels as well as renewable fuels. This assignment addresses the question how biomass may be used more efficiently and economically than it is being used today. Wider use of biomass, a clean and renewable feedstock may extend the lifetime of our fossil fuels resources and alleviate global warming problems. Another advantage of using of biomass as a source of energy is to make developed countries less interdependent on oil-exporting countries, and thereby reduce political tension. Furthermore, the economies of agricultural regions growing energy crops benefit as new jobs are created. Keywords: energy, gasification, sustainable, wet biomass

11. A review of biomass gasification technologies in Denmark and Sweden

DEFF Research Database (Denmark)

Ridjan, Iva; Mathiesen, Brian Vad; Connolly, David

This report provides an overview of existing technologies and projects in Denmark and Sweden with a focus on the Öresund region. Furthermore it presents the research and development of biomass gasification in the region and these two countries. The list of existing gasification plants from...... laboratory scale projects to big scale plants is given. The report ends with an overview of future gasification projects as well as potential experience exchanges that could occur between the countries. We regard biomass gasification as one of the key technologies in future renewable energy systems....

12. Automotive fuels from biomass via gasification

International Nuclear Information System (INIS)

Zhang, Wennan

2010-01-01

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)

13. Co-gasification of coal and biomass: Synergy, characterization and reactivity of the residual char.

Science.gov (United States)

Hu, Junhao; Shao, Jingai; Yang, Haiping; Lin, Guiying; Chen, Yingquan; Wang, Xianhua; Zhang, Wennan; Chen, Hanping

2017-11-01

The synergy effect between coal and biomass in their co-gasification was studied in a vertical fixed bed reactor, and the physic-chemical structural characteristics and gasification reactivity of the residual char obtained from co-gasification were also investigated. The results shows that, conversion of the residual char and tar into gas is enhanced due to the synergy effect between coal and biomass. The physical structure of residual char shows more pore on coal char when more biomass is added in the co-gasification. The migration of inorganic elements between coal and biomass was found, the formation and competitive role of K 2 SiO 3 , KAlSiO 4 , and Ca 3 Al 2 (SiO 4 ) 3 is a mechanism behind the synergy. The graphization degree is enhanced but size of graphite crystallite in the residual char decreases with biomass blending ratio increasing. TGA results strongly suggest the big difference in the reactivity of chars derived from coal and biomass in spite of influence from co-gasification. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

Energy Technology Data Exchange (ETDEWEB)

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

1996-12-31

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

15. Investigations on catalyzed steam gasification of biomass

Energy Technology Data Exchange (ETDEWEB)

Mudge, L.K.; Weber, S.L.; Mitchell, D.H.; Sealock, L.J. Jr.; Robertus, R.J.

1981-01-01

The purpose of the study is to evaluate the technical and economic feasibility of producing specific gas products via the catalytic gasification of biomass. This report presents the results of research conducted from December 1977 to October 1980. The study was comprised of laboratory studies, process development, and economic analyses. The laboratory studies were conducted to develop operating conditions and catalyst systems for generating methane-rich gas, synthesis gases, hydrogen, and carbon monoxide; these studies also developed techniques for catalyst recovery, regeneration, and recycling. A process development unit (PDU) was designed and constructed to evaluate laboratory systems at conditions approximating commercial operations. The economic analyses, performed by Davy McKee, Inc. for PNL, evaluated the feasibility of adapting the wood-to-methane and wood-to-methanol processes to full-scale commercial operations. Plants were designed in the economic analyses to produce fuel-grade methanol from wood and substitute natural gas (SNG) from wood via catalytic gasification with steam.

16. A critical review on biomass gasification, co-gasification, and their environmental assessments

Directory of Open Access Journals (Sweden)

2016-12-01

Full Text Available Gasification is an efficient process to obtain valuable products from biomass with several potential applications, which has received increasing attention over the last decades. Further development of gasification technology requires innovative and economical gasification methods with high efficiencies. Various conventional mechanisms of biomass gasification as well as new technologies are discussed in this paper. Furthermore, co-gasification of biomass and coal as an efficient method to protect the environment by reduction of greenhouse gas (GHG emissions has been comparatively discussed. In fact, the increasing attention to renewable resources is driven by the climate change due to GHG emissions caused by the widespread utilization of conventional fossil fuels, while biomass gasification is considered as a potentially sustainable and environmentally-friendly technology. Nevertheless, social and environmental aspects should also be taken into account when designing such facilities, to guarantee the sustainable use of biomass. This paper also reviews the life cycle assessment (LCA studies conducted on biomass gasification, considering different technologies and various feedstocks.

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

Directory of Open Access Journals (Sweden)

Sharmina Begum

2013-12-01

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

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

Directory of Open Access Journals (Sweden)

Lucio Zaccariello

2015-08-01

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

19. Gasification of sawdust in pressurised internally circulating fluidized bed

Energy Technology Data Exchange (ETDEWEB)

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

1996-12-31

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

20. BIOMASS REACTIVITY IN GASIFICATION BY THE HYNOL PROCESS

Science.gov (United States)

A thermobalance reactor was used to evaluate the reactivity of poplar wood in gasification under the operating conditions specific for the Hynol process where biomass is gasified at 30 atm and 800E C with a hydrogen-rich gas recycled from methane synthesis. The gasification invol...

1. Fixed-bed gasification research using US coals. Volume 4. Gasification of Leucite Hills subbituminous coal

Energy Technology Data Exchange (ETDEWEB)

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

1985-03-31

A single-staged, fixed-bed Wellman-Galusha gasifier coupled with a hot, raw gas combustion system and scrubber has been used to gasify numerous coals from throughout the United States. The gasification test program is organized as a cooperative effort by private industrial participants and governmental agencies. The consortium of participants is organized under the Mining and Industrial Fuel Gas (MIFGa) Group. This report is the fourth volume in a series of reports describing the atmospheric pressure, fixed-bed gasification of US coals. This specific report describes the gasification of Leucite Hills subbituminous coal from Sweetwater County, Wyoming. The period of the gasification test was April 11-30, 1983. 4 refs., 23 figs., 27 tabs.

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

Energy Technology Data Exchange (ETDEWEB)

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

2011-05-28

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

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

Science.gov (United States)

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

2016-09-01

Biochar is a promising catalyst/support for biomass gasification. Hydrogen production from biomass steam gasification with biochar or Ni-based biochar has been investigated using a two stage fixed bed reactor. Commercial activated carbon was also studied as a comparison. Catalyst was prepared with an impregnation method and characterized by X-ray diffraction, specific surface and porosity analysis, X-ray fluorescence and scanning electron micrograph. The effects of gasification temperature, steam to biomass ratio, Ni loading and bio-char properties on catalyst activity in terms of hydrogen production were explored. The Ni/AC catalyst showed the best performance at gasification temperature of 800°C, S/B=4, Ni loading of 15wt.%. Texture and composition characterization of the catalysts suggested the interaction between volatiles and biochar promoted the reforming of pyrolysis volatiles. Cotton-char supported Ni exhibited the highest activity of H2 production (64.02vol.%, 92.08mgg(-1) biomass) from biomass gasification, while rice-char showed the lowest H2 production. Copyright © 2016 Elsevier Ltd. All rights reserved.

4. Gasification experience with biomass and wastes

Energy Technology Data Exchange (ETDEWEB)

Schiffer, H.P.; Adlhoch, W. [Rheinbraun AG, Cologne (Germany)

1996-12-31

The HTW process is particularly favourable for the gasification of low-rank feedstocks. During various tests - performed in b-bench- scale, pilot-scale and industrial scale units - consequences with regard to feedstock preparation. Gasification behaviour, corrosion, emission and residual matter were carefully studied for a large number of different feedstocks. Information is now available for optimal utilisation of several types of biomass and waste materials in relation to plant operation, emission and residue utilization. Different types of biomass were tested in bench-scale conditions in an atmospheric HTW process development unit. Industrial-scale experience concerning biomass is available from the Gasification plant at Oulu, Finland, which operated from 1988 to 1991, producing ammonia synthesis gas from dried Finnish peat. During several test campaigns performed at the HTW demonstration plant sewage sludge, loaded coke and used plastics were co-gasified at feeding rates of up to 5 t/h. Operability, conversion efficiency, syngas contaminants, solid residue characteristics and emissions were monitored very carefully. Co-gasification in a dried lignite mixture allows synthesis gas for methanol production to be obtained also from waste materials. Thus, waste is converted into a useful chemical feedstock. For both sewage sludge and loaded coke, conversion efficiency and syngas yield were sufficient. Within the scope of a solid residue characterization various contaminants, including chlorine, sulphur, heavy metals and other trace elements or organic compounds, their formation and/or release were detected. Emissions were well below the limits. However, an increase in the benzene and naphthalene concentrations in the crude gas occurred. Thus, a commercial application requires additional gas treatment. In the next few years, feedstock recycling of mixed plastics household waste from Duales System Deutschland GmbH will call for a plant capacity of 350 000 to 400 000

5. BIOMASS GASIFICATION AND POWER GENERATION USING ADVANCED GAS TURBINE SYSTEMS

Energy Technology Data Exchange (ETDEWEB)

David Liscinsky

2002-10-20

6. Non-catalytic co-gasification of sub-bituminous coal and biomass

Science.gov (United States)

Nyendu, Guevara Che

Fluidization characteristics and co-gasification of pulverized sub-bituminous coal, hybrid poplar wood, corn stover, switchgrass, and their mixtures were investigated. Co-gasification studies were performed over temperature range from 700°C to 900°C in different media (N2, CO2, steam) using a bubbling fluidized bed reactor. In fluidization experiments, pressure drop (Delta P) observed for coal-biomass mixtures was higher than those of single coal and biomass bed materials in the complete fluidization regime. There was no systematic trend observed for minimum fluidization velocity ( Umf) with increasing biomass content. However, porosity at minimum fluidization (εmf) increased with increasing biomass content. Channeling effects were observed in biomass bed materials and coal bed with 40 wt.% and 50 wt.% biomass content at low gas flowrates. The effect of coal pressure overshoot reduced with increasing biomass content. Co-gasification of coal and corn stover mixtures showed minor interactions. Synergetic effects were observed with 10 wt.% corn stover. Coal mixed with corn stover formed agglomerates during co-gasification experiments and the effect was severe with increase in corn stover content and at 900°C. Syngas (H2 + CO) concentrations obtained using CO2 as co-gasification medium were higher (~78 vol.% at 700°C, ~87 vol.% at 800°C, ~93 vol.% at 900°C) than those obtained with N2 medium (~60 vol.% at 700°C, ~65 vol.% at 800°C, ~75 vol.% at 900°C). Experiments involving co-gasification of coal with poplar showed no synergetic effects. Experimental yields were identical to predicted yields. However, synergetic effects were observed on H2 production when steam was used as the co-gasification medium. Additionally, the presence of steam increased H2/CO ratio up to 2.5 with 10 wt.% hybrid poplar content. Overall, char and tar yields decreased with increasing temperature and increasing biomass content, which led to increase in product gas.

7. The development situation of biomass gasification power generation in China

International Nuclear Information System (INIS)

Zhou, Zhaoqiu; Yin, Xiuli; Xu, Jie; Ma, Longlong

2012-01-01

This work presents the development situation of biomass gasification power generation technology in China and analyzes the difficulty and challenge in the development process. For China, a large agricultural country with abundant biomass resources, the utilization of biomass gasification power generation technology is of special importance, because it can contribute to the electricity structure diversification under the present coal-dominant electricity structure, ameliorate the environmental impact, provide energy to electricity-scarce regions and solve the problems facing agriculture. Up to now, China has developed biomass gasification power generation plants of different types and scales, including simple gas engine-based power generation systems with capacity from several kW to 3 MW and integrated gasification combined cycle systems with capacity of more than 5 MW. In recent years, due to the rising cost of biomass material, transportation, manpower, etc., the final cost of biomass power generation has increased greatly, resulting in a serious challenge in the Chinese electricity market even under present preferential policy for biomass power price. However, biomass gasification power generation technology is generally in accord with the characteristics of biomass resources in China, has relatively good adaptability and viability, and so has good prospect in China in the future. - Highlights: ► Biomass gasification power generation of 2 kW–2 MW has wide utilization in China. ► 5.5 MW biomass IGCC demonstration plant has maximum power efficiency of up to 30%. ► Biomass power generation is facing a serious challenge due to biomass cost increase.

8. Operational characteristics of a 1.2-MW biomass gasification and power generation plant.

Science.gov (United States)

Wu, Chuang-zhi; Yin, Xiu-li; Ma, Long-long; Zhou, Zhao-qiu; Chen, Han-ping

2009-01-01

In this study, we analyzed the operational characteristics of a 1.2-MW rice husk gasification and power generation plant located in Changxing, Zhejiang province, China. The influences of gasification temperature, equivalence ratio (ER), feeding rate and rice husk water content on the gasification characteristics in a fluidized bed gasifier were investigated. The axial temperature profile in the dense phase of the gasifier showed that inadequate fluidization occurred inside the bed, and that the temperature was closely related to changes in ER and feeding rate. The bed temperature increased linearly with increasing ER when the feeding rate was kept constant, while a higher feeding rate corresponded to a lower bed temperature at fixed ER. The gas heating value decreased with increasing temperature, while the feeding rate had little effect. When the gasification temperature was 700-800 degrees C, the gas heating value ranged from 5450-6400 kJ/Nm(3). The water content of the rice husk had an obvious influence on the operation of the gasifier: increases in water content up to 15% resulted in increasing ER and gas yield, while water contents above 15% caused aberrant temperature fluctuations. The problems in this plant are discussed in the light of operational experience of MW-scale biomass gasification and power generation plants.

9. Preparation and development of Ni/Olivine catalysts for hydrogen production by means of biomass gasification in fluidized bed; Elaboration et developpement d'un catalyseur Ni/Olivine pour la production d'hydrogene par gazeification de la biomasse en lit fluidise

Energy Technology Data Exchange (ETDEWEB)

Swierczynski, D

2004-10-01

Biomass gasification is one of the most interesting ways to valorize this widely accessible source of renewable energy. This process, realized in fluidized bed at high temperature (800-900 C), permits to obtain syngas (mainly H{sub 2}, and CO) which contains however the unwanted sub-products CH{sub 4} and tars. Their catalytic elimination is the key step of the process and permits to clean up the product gas as well as to increase the quantity of H{sub 2} produced. This work describes the development of a catalyst for steam gasification of biomass, designed for fluidized bed, and active for tar and methane reforming. For this we have integrated Ni with natural olivine (Mg{sub 0.9}Fe{sub 0.1})2SiO{sub 4}. Characterization by different techniques (XRD, TPR, SEM, TEM, Moessbauer) showed that during calcination in air, oxidation of olivine leads to a rejection of part of iron (II) from its structure with formation of iron (III) oxides.The catalysts Ni/olivine are obtained by wet impregnation of olivine with an aqueous solution of nickel salt, followed by calcination which leads to a reaction between NiO and olivine. This results in formation of a NiO-MgO solid solution grafted on the support surface and assuring attrition resistance. The catalytic activity was firstly studied in fixed bed in dry reforming of methane, then in steam reforming of tars with toluene as model compound. For both reactions the optimized system showed high activity and selectivity for syngas as well as an excellent stability explained by the presence of the NiO-MgO on the support surface and by formation of Ni-Fe alloys permitting to limit strongly carbon formation and providing long life for the catalyst. Finally the catalyst preparation was scaled-up to 100 kg and its efficacy was confirmed in biomass steam gasification in 100 kWth fluidized bed reactor permitting to envisage its industrial use. (author)

10. GASIFICATION BASED BIOMASS CO-FIRING - PHASE I; SEMIANNUAL

International Nuclear Information System (INIS)

Babul Patel; Kevin McQuigg; Robert F. Toerne

2001-01-01

Biomass gasification offers a practical way to use this locally available fuel source for co-firing traditional large utility boilers. The gasification process converts biomass into a low Btu producer gas that can be fed directly into the boiler. This strategy of co-firing is compatible with variety of conventional boilers including natural gas fired boilers as well as pulverized coal fired and cyclone boilers. Gasification has the potential to address all problems associated with the other types of co-firing with minimum modifications to the existing boiler systems. Gasification can also utilize biomass sources that have been previously unsuitable due to size or processing requirements, facilitating a reduction in the primary fossil fuel consumption in the boiler and thereby reducing the greenhouse gas emissions to the atmosphere

11. GASIFICATION BASED BIOMASS CO-FIRING - PHASE I

Energy Technology Data Exchange (ETDEWEB)

Babul Patel; Kevin McQuigg; Robert F. Toerne

2001-12-01

Biomass gasification offers a practical way to use this locally available fuel source for co-firing traditional large utility boilers. The gasification process converts biomass into a low Btu producer gas that can be fed directly into the boiler. This strategy of co-firing is compatible with variety of conventional boilers including natural gas fired boilers as well as pulverized coal fired and cyclone boilers. Gasification has the potential to address all problems associated with the other types of co-firing with minimum modifications to the existing boiler systems. Gasification can also utilize biomass sources that have been previously unsuitable due to size or processing requirements, facilitating a reduction in the primary fossil fuel consumption in the boiler and thereby reducing the greenhouse gas emissions to the atmosphere.

12. Analysis of tars produced in biomass gasification

Energy Technology Data Exchange (ETDEWEB)

Zhou, J.; Wang, Y.; Kinoshita, C.M. [Univ. of Hawaii, Honolulu, HI (United States)

1993-12-31

Parametric tests on tar formation, varying temperature, equivalence ratio, and residence time, are performed on a bench-scale, indirectly-heated fluidized bed gasifier. Prepared tar samples are analyzed in a gas chromatograph (GC) with a flame ionization detector, using a capillary column. Standards containing dominant tar species have been prepared for GC calibration. The identified peaks include single-ring hydrocarbons, such as benzene, to five-ring hydrocarbons, such as perylene; depending on the gasification conditions, the identified species represent about 70 to 90% (mass basis) of the tar constituents. Under all conditions tested, benzene and naphthalene were the most dominant species. Temperature and equivalence ratio have significant effect on tar yield and tar composition. Tar yield decreases with increasing temperature or equivalence ratio. The test results suggest that lower temperature favors the formation of more aromatic tar species with diversified substituent groups, while higher temperature favors the formation of fewer aromatic tar species without substituent groups. Higher temperature or equivalence ratio favors the formation of polyaromatic compounds. Oxygen-containing compounds exist in significant quantities only at temperature below 800{degrees}C and decrease with increasing temperature, equivalence ratio, or residence time.

13. Biomass gasification for liquid fuel production

Energy Technology Data Exchange (ETDEWEB)

Najser, Jan, E-mail: jan.najser@vsb.cz, E-mail: vaclav.peer@vsb.cz; Peer, Václav, E-mail: jan.najser@vsb.cz, E-mail: vaclav.peer@vsb.cz [VSB - Technical university of Ostrava, Energy Research Center, 17. listopadu 15/2172, 708 33 Ostrava-Poruba (Czech Republic); Vantuch, Martin [University of Zilina, Faculty of Mechanical Engineering, Department of Power Engineering, Univerzitna 1, 010 26 Zilina (Slovakia)

2014-08-06

In our old fix-bed autothermal gasifier we tested wood chips and wood pellets. We make experiments for Czech company producing agro pellets - pellets made from agricultural waste and fastrenewable natural resources. We tested pellets from wheat and rice straw and hay. These materials can be very perspective, because they dońt compete with food production, they were formed in sufficient quantity and in the place of their treatment. New installation is composed of allothermal biomass fixed bed gasifier with conditioning and using produced syngas for Fischer - Tropsch synthesis. As a gasifying agent will be used steam. Gas purification will have two parts - separation of dust particles using a hot filter and dolomite reactor for decomposition of tars. In next steps, gas will be cooled, compressed and removed of sulphur and chlorine compounds and carbon dioxide. This syngas will be used for liquid fuel synthesis.

14. Biomass gasification for liquid fuel production

Science.gov (United States)

Najser, Jan; Peer, Václav; Vantuch, Martin

2014-08-01

In our old fix-bed autothermal gasifier we tested wood chips and wood pellets. We make experiments for Czech company producing agro pellets - pellets made from agricultural waste and fastrenewable natural resources. We tested pellets from wheat and rice straw and hay. These materials can be very perspective, because they dońt compete with food production, they were formed in sufficient quantity and in the place of their treatment. New installation is composed of allothermal biomass fixed bed gasifier with conditioning and using produced syngas for Fischer - Tropsch synthesis. As a gasifying agent will be used steam. Gas purification will have two parts - separation of dust particles using a hot filter and dolomite reactor for decomposition of tars. In next steps, gas will be cooled, compressed and removed of sulphur and chlorine compounds and carbon dioxide. This syngas will be used for liquid fuel synthesis.

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

Energy Technology Data Exchange (ETDEWEB)

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

1997-10-01

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

16. Fixed-bed gasification research using US coals. Volume 9. Gasification of Elkhorn bituminous coal

Energy Technology Data Exchange (ETDEWEB)

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

1985-05-01

A single-staged, fixed-bed Wellman-Galusha gasifier coupled with a hot, raw gas combustion system and scrubber has been used to gasify numerous coals from throughout the United States. The gasification test program is organized as a cooperative effort by private industrial participants and governmental agencies. The consortium of participants is organized under the Mining and Industrial Fuel Gas (MIFGa) group. This report is the ninth volume in a series of reports describing the atmospheric pressure, fixed-bed gasification of US coals. This specific report describes the gasification of Elkhorn bituminous coal. The period of gasificastion test was September 13 to October 12, 1983. 9 refs., 24 figs., 35 tabs.

17. Gasification of Coal and PET in Fluidized Bed Reactor

Czech Academy of Sciences Publication Activity Database

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

2006-01-01

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

18. Bio-syngas production from agro-industrial biomass residues by steam gasification.

Science.gov (United States)

Pacioni, Tatiana Ramos; Soares, Diniara; Domenico, Michele Di; Rosa, Maria Fernanda; Moreira, Regina de Fátima Peralta Muniz; José, Humberto Jorge

2016-12-01

This study evaluated the steam gasification potential of three residues from Brazilian agro-industry by assessing their reaction kinetics and syngas production at temperatures from 650 to 850°C and a steam partial pressure range of 0.05 to 0.3bar. The transition temperature between kinetic control and diffusion control regimes was identified. Prior to the gasification tests, the raw biomasses, namely apple pomace, spent coffee grounds and sawdust, were pyrolyzed in a fixed-bed quartz tubular reactor under controlled conditions. Gasification tests were performed isothermally in a magnetic suspension thermobalance and the reaction products were analyzed by a gas chromatograph with TCD/FID detectors. According to the characterization results, the samples presented higher carbon and lower volatile matter contents than the biomasses. Nevertheless, all of the materials had high calorific value. Syngas production was influenced by both temperature and steam partial pressure. Higher concentrations of H 2 and CO were found in the conversion range of 50-80% and higher concentrations of CO 2 in conversions around 10%, for all the gasified biochars. The H 2 /CO decreased with increasing temperature, mainly in kinetic control regime, in the lower temperature range. The results indicate the gasification potential of Brazilian biomass residues and are an initial and important step in the development of gasification processes in Brazil. Copyright © 2016 Elsevier Ltd. All rights reserved.

19. 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.

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

Energy Technology Data Exchange (ETDEWEB)

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

1995-12-31

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

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

Energy Technology Data Exchange (ETDEWEB)

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

1996-12-01

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

2. High-temperature entrained flow gasification of biomass

DEFF Research Database (Denmark)

Qin, Ke; Lin, Weigang; Jensen, Peter Arendt

2012-01-01

Biomass (wood and straw) gasification has been studied in a laboratory scale atmospheric pressure entrained flow reactor. Effects of reaction temperature, steam/carbon molar ratio, excess air ratio, and biomass type on the solid, liquid and gas products were investigated. The biomass was completely...... soot. Increasing excess air ratio from 0.25 to 0.50 gave no significant change in the producer gas yield, but the yields of H2, CO, and soot decreased, the CO2 yield increased, and the molar ratio of H2/CO decreased. Moreover, wood and straw gasification provided similar product compositions. At 1350°C...

3. Assessing the gasification potential of five woodchips species by employing a lab-scale fixed-bed downdraft reactor

International Nuclear Information System (INIS)

Sarker, Shiplu; Nielsen, Henrik Kofoed

2015-01-01

Highlights: • Fixed-bed downdraft lab scale gasification of 3 forest and 2 energy crops. • Gasification condition was varied in-terms of ER (0.19–0.80). • Energy crops gave mean bed temperature >750 °C and highest H 2 yield. • Spruce resulted inferior gasification performance than that of the other biomass. - Abstract: This paper is aimed to assess the performance of air blown fixed-bed downdraft gasification of local lignocellulosic biomasses which in perspective of Southern Norway are both available and sustainable. Long rotation forest crops birch, oak and spruce, coupled with energy crops poplar and willow were used as feedstocks. The gasification conditions undertaken were widely varied in-terms of air (∼3.20–4.20 N m 3 /h) and fuel flow (∼1.70–2.10 kg/h) so that the corresponding equivalence ratio (ER) differed (0.19–0.80) and ultimately reflected to other operational parameters such as bed temperature (∼550–760 °C maximum), producer gas yield (∼1.50–2.30 N m 3 /kg, wet base), cold gas efficiency (∼35–51%), carbon conversion efficiency (∼61–76%) and so on. An emphasis was also placed on evaluating material balance by accounting the by-products (such as tar, char) of gasification so that the system reliability is identified. Overall, the gasification performance of different woody biomass was found viable over a broad range of operating condition which is appealing in contributing this technology in the context of regional bioenergy and thus towards the renewable energy

4. Release characteristics of alkali and alkaline earth metallic species during biomass pyrolysis and steam gasification process.

Science.gov (United States)

Long, Jiang; Song, Hu; Jun, Xiang; Sheng, Su; Lun-Shi, Sun; Kai, Xu; Yao, Yao

2012-07-01

Investigating the release characteristics of alkali and alkaline earth metallic species (AAEMs) is of potential interest because of AAEM's possible useful service as catalysts in biomass thermal conversion. In this study, three kinds of typical Chinese biomass were selected to pyrolyse and their chars were subsequently steam gasified in a designed quartz fixed-bed reactor to investigate the release characteristics of alkali and alkaline earth metallic species (AAEMs). The results indicate that 53-76% of alkali metal and 27-40% of alkaline earth metal release in pyrolysis process, as well as 12-34% of alkali metal and 12-16% of alkaline earth metal evaporate in char gasification process, and temperature is not the only factor to impact AAEMs emission. The releasing characteristics of AAEMs during pyrolysis and char gasification process of three kinds of biomass were discussed in this paper. Copyright © 2012 Elsevier Ltd. All rights reserved.

5. Thermal gasification of village rice husk and sawdust in fluidized bed : gasifier operation and thermal efficiency

Energy Technology Data Exchange (ETDEWEB)

Gangavati, P.B. [Basaveshwar Engineering College, Bagalkot (India); Mishra, I.M.; Prasad, B. [Indian Inst. of Technology, Roorkee (India). Dept. of Chemical Engineering

2006-07-01

An air gasification process for converting rice husks into a renewable fuel was presented. The gasification process was conducted on a fluidized bed gasifier unit comprised of a fluidized bed reactor; an air supply unit; biomass-feeding unit; a high efficiency cyclone; and an after-burner. The performance of the gasifier was evaluated under a range of different operating conditions, fluidization velocities, and equivalence ratios. The aim of the study was to understand the gasification characteristics of the rice husk and compare it with the kinetic behaviour of sawdust. Temperature profiles were analyzed, as well as gas composition and heating values, as well as carbon conversion and thermal efficiencies. The results of the gasification experiments indicated that thermal efficiencies decreased as the fluidization velocity increased. The gas yield increased and the higher heating values decreased with increases in the equivalence ratio (ER) at all the tested velocities. A maximum efficiency of approximately 57 per cent was obtained for the village rice husk, while efficiencies of 72.3 per cent were obtained for the sawdust. 7 ref., 2 figs.

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

Directory of Open Access Journals (Sweden)

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.

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

DEFF Research Database (Denmark)

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

2008-01-01

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

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

Science.gov (United States)

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

2012-04-01

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

9. Hydrogen Production Cost Estimate Using Biomass Gasification: Independent Review

Energy Technology Data Exchange (ETDEWEB)

none,

2011-10-01

This independent review is the conclusion arrived at from data collection, document reviews, interviews and deliberation from December 2010 through April 2011 and the technical potential of Hydrogen Production Cost Estimate Using Biomass Gasification. The Panel reviewed the current H2A case (Version 2.12, Case 01D) for hydrogen production via biomass gasification and identified four principal components of hydrogen levelized cost: CapEx; feedstock costs; project financing structure; efficiency/hydrogen yield. The panel reexamined the assumptions around these components and arrived at new estimates and approaches that better reflect the current technology and business environments.

10. Tar removal from biomass gasification streams: processes and catalysts

International Nuclear Information System (INIS)

Quitete, Cristina P.B.; Souza, Mariana M.V.M.

2014-01-01

Biomass gasification is a technology that has attracted great interest in synthesis of biofuels and oxo alcohols. However, this gas contains several contaminants, including tar, which need to be removed. Removal of tar is particularly critical because it can lead to operational problems. This review discusses the major pathways to remove tar, with a particular focus on the catalytic steam reforming of tar. Few catalysts have shown promising results; however, long-term studies in the context of real biomass gasification streams are required to realize their potential. (author)

11. Catalytic gasification in fluidized bed, of orange waste. Comparison with non catalytic gasification

International Nuclear Information System (INIS)

Aguiar Trujillo, Leonardo; Marquez Montesinos, Francisco; Ramos Robaina, Boris A.; Guerra Reyes, Yanet; Arauzo Perez, Jesus; Gonzalo Callejo, Alberto; Sanchez Cebrian, Jose L

2011-01-01

The industry processing of the orange, generates high volumes of solid waste. This waste has been used as complement in the animal feeding, in biochemical processes; but their energy use has not been valued by means of the gasification process. They were carried out gasification studies with air in catalytic fluidized bed (using dolomite and olivine as catalysts in a secondary reactor, also varying the temperature of the secondary reactor and the catalyst mass), of the solid waste of orange and the results are compared with those obtained in the gasification with non catalytic air. In the processes we use a design of complete factorial experiment of 2k, valuing the influence of the independent variables and their interactions in the answers, using the software Design-Expert version 7 and a grade of significance of 95 %. The results demonstrate the qualities of the solid waste of orange in the energy use by means of the gasification process for the treatment of these residuals, obtaining a gas of low caloric value. The use of catalysts also diminishes the yield of tars obtained in the gasification process, being more active the dolomite that the olivine in this process. (author)

12. Solid Oxide Fuel Cells coupled with a biomass gasification unit

Directory of Open Access Journals (Sweden)

Skrzypkiewicz Marek

2016-01-01

Full Text Available A possibility of fuelling a solid oxide fuel cell stack (SOFC with biomass fuels can be realized by coupling a SOFC system with a self-standing gasification unit. Such a solution enables multi-fuel operation, elasticity of the system as well as the increase of the efficiency of small-scale biomass-to-electricity conversion units. A system of this type, consisting of biomass gasification unit, gas purification unit, SOFC stack, anode off-gas afterburner and peripherals was constructed and operated successfully. During the process, biomass fuel (wood chips was gasified with air as gasification agent. The gasifier was capable of converting up to 30 kW of fuel to syngas with efficiencies up to 75%. Syngas leaving the gasification unit is delivered to a medium temperature adsorber for sulphur compounds removal. Steam is added to the purified fuel to maintain steam to carbon ratio higher than 2. The syngas then is passed to a SOFC stack through a fuel preheater. In such a configuration it was possible to operate a commercial 1.3 kW stack within its working regime. Conducted tests confirmed successful operation of a SOFC stack fuelled by biomass-sourced syngas.

13. 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.

14. A numerical model of a fluidized bed biomass gasifier

Energy Technology Data Exchange (ETDEWEB)

Hongming Jiang; Morey, R.V. (Minnesota Univ., St. Paul, MN (United States). Dept. of Agricultural Engineering)

1992-01-01

A one-dimensional, steady state, numerical model was developed for a fluidized bed biomass gasifier. The gasifier model consists of a fuel pyrolysis model, an oxidation model, a gasification model and a freeboard model. Given the bed temperature, ambient air flow rate and humidity ratio, fuel moisture content and reactor parameters, the model predicts the fuel feed rate for steady state operation, composition of the producer gas and fuel energy conversion. The gasifier model was validated with experimental results. The effects of major mechanisms (fuel pyrolysis and the chemical and the physical rate processes) were assessed in a sensitivity study of the gasification model. A parametric study was also conducted for the gasifier model. It is concluded that the model can be used for gasifier performance analysis. (author)

15. Biomass Gasification Technology Assessment: Consolidated Report

Energy Technology Data Exchange (ETDEWEB)

Worley, M.; Yale, J.

2012-11-01

Harris Group Inc. (HGI) was commissioned by the National Renewable Energy Laboratory to assess gasification and tar reforming technologies. Specifically, the assessments focused on gasification and tar reforming technologies that are capable of producing a syngas suitable for further treatment and conversion to liquid fuels. HGI gathered sufficient information to analyze three gasification and tar reforming systems. This report summarizes the equipment, general arrangement of the equipment, operating characteristics, and operating severity for each technology. The order of magnitude capital cost estimates are supported by a basis-of-estimate write-up, which is also included in this report. The report also includes Microsoft Excel workbook models, which can be used to design and price the systems. The models can be used to analyze various operating capacities and pressures. Each model produces a material balance, equipment list, capital cost estimate, equipment drawings and preliminary general arrangement drawings. Example outputs of each model are included in the Appendices.

16. Experimental fact-finding in CFB biomass gasification for ECN's 500 kWth pilot-plant

NARCIS (Netherlands)

Kersten, Sascha R.A.; Prins, W.; van der Drift, A.; van Swaaij, Willibrordus Petrus Maria

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

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

Energy Technology Data Exchange (ETDEWEB)

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

1996-12-01

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

18. Gasification of peat and biomass in suspension. Turpeen ja biomassan suspensiokaasutus

Energy Technology Data Exchange (ETDEWEB)

Haukka, P.; Raiko, R.

1993-01-01

Gasification of peat and biomass in dilute particle-gas suspension has not been studied significantly in Finland, even though these fuels require drying, which often produces dry pulverized fuel. This report has concentrated on studying suitability of so-called two-stage entrained-bed gasification for peat and biomass. The gasification system consists of a pyrolysis reactor (entrained flow) and an adiabatic char combustor. Dry or almost dry fuel is fed into the hot flue gas stream coming from the char combustor. Gasification is based on flash pyrolysis in the dilute suspension flow. Residual char is separated from pyrolyzer gases in a gas cleaning device and fed back to the adiabatic combustor. In the combustor char is burned at high temperature to supply the heat required to support endothermic reactions occurring in the pyrolyzer. To study entrained-bed gasification two types of computer models were developed: steady state simulation model and kinetic pyrolyzer model. With the help of these computer models mass and energy balances of the gasifier can be solved and the main dimensions of the gasifier can be determined. Lack of proper kinetic parameters for fast pyrolysis of peat and biomass makes it more difficult to apply the kinetic model in practice. Quantitative data concerning fast pyrolysis in dilute gas-particle suspension are needed to be able to evaluate the performance of the suspension gasifier in more detail. Gasifier operation has been studied using three different levels for amounts of pyrolysis pro- ducts, nine pressure levels between 15-23 bars and five temperature levels between 800-1200 deg C. Furthermore, normal pressure performance was simulated. In addition to simulation studies product gas heating value was optimized

19. Thermodynamic analysis of hydrogen production from biomass gasification

International Nuclear Information System (INIS)

Cohce, M.K.; Dincer, I.; Rosen, M.A.

2009-01-01

'Full Text': Biomass resources have the advantage of being renewable and can therefore contribute to renewable hydrogen production. In this study, an overview is presented of hydrogen production methods in general, and biomass-based hydrogen production in particular. For two methods in the latter category (direct gasification and pyrolysis), assessments are carried out, with the aim of investigating the feasibility of producing hydrogen from biomass and better understanding the potential of biomass as a renewable energy source. A simplified model is presented here for biomass gasification based on chemical equilibrium considerations, and the effects of temperature, pressure and the Gibbs free energy on the equilibrium hydrogen yield are studied. Palm oil (designated C 6 H 10 O 5 ), one of the most common biomass resources in the world, is considered in the analyses. The gasifier is observed to be one of the most critical components of a biomass gasification system, and is modeled using stoichiometric reactions. Various thermodynamic efficiencies are evaluated, and both methods are observed to have reasonably high efficiencies. (author)

20. Gasification and co-gasification of biomass wastes: Effect of the biomass origin and the gasifier operating conditions

Energy Technology Data Exchange (ETDEWEB)

Lapuerta, Magin; Hernandez, Juan J.; Pazo, Amparo; Lopez, Julio [Universidad de Castilla-La Mancha, Escuela Tecnica Superior de Ingenieros Industriales (Edificio Politecnico), Avenida Camilo Jose Cela s/n. 13071 Ciudad Real (Spain)

2008-09-15

Air gasification of different biomass fuels, including forestry (pinus pinaster pruning) and agricultural (grapevine and olive tree pruning) wastes as well as industry wastes (sawdust and marc of grape), has been carried out in a circulating flow gasifier in order to evaluate the potential of using these types of biomass in the same equipment, thus providing higher operation flexibility and minimizing the effect of seasonal fuel supply variations. The potential of using biomass as an additional supporting fuel in coal fuelled power plants has also been evaluated through tests involving mixtures of biomass and coal-coke, the coke being a typical waste of oil companies. The effect of the main gasifier operating conditions, such as the relative biomass/air ratio and the reaction temperature, has been analysed to establish the conditions allowing higher gasification efficiency, carbon conversion and/or fuel constituents (CO, H{sub 2} and CH{sub 4}) concentration and production. Results of the work encourage the combined use of the different biomass fuels without significant modifications in the installation, although agricultural wastes (grapevine and olive pruning) could to lead to more efficient gasification processes. These latter wastes appear as interesting fuels to generate a producer gas to be used in internal combustion engines or gas turbines (high gasification efficiency and gas yield), while sawdust could be a very adequate fuel to produce a H{sub 2}-rich gas (with interest for fuel cells) due to its highest reactivity. The influence of the reaction temperature on the gasification characteristics was not as significant as that of the biomass/air ratio, although the H{sub 2} concentration increased with increasing temperature. (author)

1. Pretreatment and Feeding of Biomass for Pressurized Entrained Flow Gasification

Czech Academy of Sciences Publication Activity Database

Svoboda, Karel; Pohořelý, Michael; Hartman, Miloslav; Martinec, J.

2009-01-01

Roč. 90, č. 5 (2009), s. 629-635 ISSN 0378-3820 R&D Projects: GA AV ČR IAA400720701 Grant - others:RFCS(XE) CT/2007/00005 Institutional research plan: CEZ:AV0Z40720504 Keywords : biomass * feeding * gasification Subject RIV: DJ - Water Pollution ; Quality Impact factor: 2.321, year: 2009

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

DEFF Research Database (Denmark)

Ahrenfeldt, Jesper; Egsgaard, Helge; Stelte, Wolfgang

2013-01-01

and conversion. The study identifies the following major impact factors regarding tar content in the producer gas: oxidation temperature, excess air ratio and biomass moisture content. In a experimental setup, wood pellets were pyrolyzed and the resulting pyrolysis gas was transferred in a heated partial...... tar destruction and a high moisture content of the biomass enhances the decomposition of phenol and inhibits the formation of naphthalene. This enhances tar conversion and gasification in the char-bed, and thus contributes in-directly to the tar destruction....

3. 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

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

Directory of Open Access Journals (Sweden)

Chr. Christodoulou

2014-11-01

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

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

NARCIS (Netherlands)

Groeneveld, M.J.; van Swaaij, Willibrordus Petrus Maria

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

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

Energy Technology Data Exchange (ETDEWEB)

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

1998-09-01

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

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

OpenAIRE

Lucio Zaccariello; Maria Laura Mastellone

2015-01-01

The effect of fuel composition on gasification process performance was investigated by performing mass and energy balances on a pre-pilot scale bubbling fluidized bed reactor fed with mixtures of plastic waste, wood, and coal. The fuels containing plastic waste produced less H 2 , CO, and CO 2 and more light hydrocarbons than the fuels including biomass. The lower heating value (LHV) progressively increased from 5.1 to 7.9 MJ/Nm 3 when the plastic waste fraction was moved from 0% to 100%. Hig...

8. Pilot-scale gasification of woody biomass

Science.gov (United States)

Thomas Elder; Leslie H. Groom

2011-01-01

The gasification of pine and mixed-hardwood chips has been carried out in a pilot-scale system at a range of gas flow rates. Consuming ~17-30 kgh-1 of feedstock, the producer gas was composed of ~200 dm3 m-3 carbon monoxide, 12 dm3 m-3 carbon dioxide, 30 dm3 m-3 methane and 190 dm3 m-3 hydrogen, with an energy content of ~6 MJ m-3 for both feedstocks. It was found that...

9. Pyrolysis and Gasification Kinetics of Large Biomass Particles

Energy Technology Data Exchange (ETDEWEB)

Svenson, Jenny; Hagstroem, Magnus; Andersson, Patrik U.; Loenn, Benny; Pettersson, Jan B.C. [Goteborg Univ. (Sweden). Dep. of Chemistry, Atmospheric Science; Davidsson, Kent O. [Chalmers Univ. of Technology, Goeteborg (Sweden). Energy Conversion

2004-05-01

The aim of the project is to provide experimental data on single biomass particle pyrolysis that have an applied as well as a fundamental bearing. Transport phenomena and kinetics on the single particle level are characterized, including heat and mass transport processes. New experimental techniques and methods are applied and developed within the project. A single-particle reactor has been developed for the investigations, and several detection techniques including fast thermogravimetric analysis, molecular beam mass spectrometry, laser spectroscopy, video recording and pyrometry are applied. The experimental data are used to develop robust models for pyrolysis and gasification, which are essential components in the design of gasification and combustion reactors.

10. Waste-gasification efficiency of a two-stage fluidized-bed gasification system.

Science.gov (United States)

Liu, Zhen-Shu; Lin, Chiou-Liang; Chang, Tsung-Jen; Weng, Wang-Chang

2016-02-01

This study employed a two-stage fluidized-bed gasifier as a gasification reactor and two additives (CaO and activated carbon) as the Stage-II bed material to investigate the effects of the operating temperature (700°C, 800°C, and 900°C) on the syngas composition, total gas yield, and gas-heating value during simulated waste gasification. The results showed that when the operating temperature increased from 700 to 900°C, the molar percentage of H2 in the syngas produced by the two-stage gasification process increased from 19.4 to 29.7mol% and that the total gas yield and gas-heating value also increased. When CaO was used as the additive, the molar percentage of CO2 in the syngas decreased, and the molar percentage of H2 increased. When activated carbon was used, the molar percentage of CH4 in the syngas increased, and the total gas yield and gas-heating value increased. Overall, CaO had better effects on the production of H2, whereas activated carbon clearly enhanced the total gas yield and gas-heating value. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

11. A comparative experimental study of biomass, lignite and hard coal steam gasification

Energy Technology Data Exchange (ETDEWEB)

Smolinski, A.; Howaniec, N.; Stanczyk, K. [Central Mining Institute, Katowice (Poland)

2011-06-15

In the paper the results of experimental comparative study on steam gasification of lignite, hard coal and energy crops, such as Spartina pectinata, Helianthus tuberosus L, Sida hermaphrodita R. and Miscanthus X Giganteus in a laboratory-scale fixed bed reactor at the temperature of 700 {sup o}C were presented. The effectiveness of steam gasification in terms of gas flows, composition and carbon conversion was tested. The ability of coal and biomass to undergo thermochemical transformations was determined based on their chars reactivities. The tested biomass samples were relatively more reactive but produced less synthesis gas and of lower calorific value. Comparison of the reactivities and other physical and chemical properties of coals and biomass, selected based on the gasification process requirements, with a use of the principal component analysis showed that biomass samples differ from the remaining samples due to the highest content of volatiles, oxygen and hydrogen in a sample and the highest amount of carbon dioxide in produced synthesis gas. Hard coals were characterized by the lowest carbon conversion and reactivities R{sub 50} and R{sub max}. Moreover, the negative correlation between the reactivity and the heat of combustion, calorific value, carbon content in a sample and total gas yield produced in the process as well as a positive correlation between R{sub 50} and R{sub max} and volatiles, oxygen content in a sample and carbon dioxide concentration in produced gas were observed.

12. Methods and apparatus for catalytic hydrothermal gasification of biomass

Science.gov (United States)

Elliott, Douglas C.; Butner, Robert Scott; Neuenschwander, Gary G.; Zacher, Alan H.; Hart, Todd R.

2012-08-14

Continuous processing of wet biomass feedstock by catalytic hydrothermal gasification must address catalyst fouling and poisoning. One solution can involve heating the wet biomass with a heating unit to a temperature sufficient for organic constituents in the feedstock to decompose, for precipitates of inorganic wastes to form, for preheating the wet feedstock in preparation for subsequent separation of sulfur contaminants, or combinations thereof. Treatment further includes separating the precipitates out of the wet feedstock, removing sulfur contaminants, or both using a solids separation unit and a sulfur separation unit, respectively. Having removed much of the inorganic wastes and the sulfur that can cause poisoning and fouling, the wet biomass feedstock can be exposed to the heterogeneous catalyst for gasification.

13. Hydrogen-rich syngas production and tar removal from biomass gasification using sacrificial tyre pyrolysis char

International Nuclear Information System (INIS)

Al-Rahbi, Amal S.; Williams, Paul T.

2017-01-01

Highlights: • Tyre char is used as catalyst and syngas source in pyrolysis-reforming of biomass. • Metals in tyre char catalyse tar decomposition. • Increased steam and higher temperature promotes H 2 production. • Syngas H 2 /CO ratio varied between 1.3 to 2. • A waste derived catalyst degrades tar and is also sacrificed for char gasification. - Abstract: Carbonaceous materials have been proven to have a high catalytic activity for tar removal from the syngas produced from biomass gasification. The simultaneous reforming and gasification of pyrolysis gases and char could have a significant role in increasing the gas yield and decreasing the tar in the product syngas. This study investigates the use of tyre char as a catalyst for H 2 -rich syngas production and tar reduction during the pyrolysis-reforming of biomass using a two stage fixed bed reactor. The biomass sample was pyrolysed under nitrogen at a pyrolysis temperature of 500 °C, the evolved pyrolysis volatiles were passed to a second stage with steam and the gases were reformed in the presence of tyre char as catalyst. The influence of catalyst bed temperature, steam to biomass ratio, reaction time and tyre ash metals were investigated. The influence of the catalytic activity of tyre ash minerals on composition of syngas and tar decomposition during the steam reforming of biomass was significant as the removal of minerals led to a decrease in the H 2 yield. Raising the steam injection rate and reforming temperature resulted in an increase in H 2 production as steam reforming and char gasification reactions were enhanced. The maximum H 2 content in the product syngas of 56 vol.% was obtained at a reforming temperature of 900 °C and with a steam to biomass mass ratio of 6 (g/g). Further investigation of the influence of the biomass:steam ratio on syngas quality showed that the H 2 :CO molar ratio was increased from 1.8 (steam: biomass ratio; 1.82 g g −1 ) to 3 (steam: biomass ratio; 6 g g −1 ).

14. Fixed-bed gasification research using US coals. Volume 11. Gasification of Minnesota peat. [Peat pellets and peat sods

Energy Technology Data Exchange (ETDEWEB)

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

1985-05-01

A single-staged, fixed-bed Wellman-Galusha gasifier coupled with a hot, raw gas combustion system and scrubber has been used to gasify numerous coals from throughout the United States. The gasification test program is organized as a coooperative effort by private industrial participants and governmental agencies. The consortium of participants is organized under the Mining and Industrial Fuel Gas (MIFGa) Group. This report is the eleventh volume in a series of reports describing the atmospheric pressure, fixed-bed gasification of US coals. This specific report describes the gasification of peat pellets and peat sods during 3 different test periods. 2 refs., 20 figs., 13 tabs.

15. Characterisation of coal and chars in fluidised bed gasification

CSIR Research Space (South Africa)

Oboirien, BO

2009-03-01

Full Text Available gasification of high-ash Chinese coal in a pilot plant. The data also shows that the mean particle sizes of the various residual char were smaller than the feed coal and the particle size of the bed char were higher than the particle of the cyclone char... and ultimate analysis Results consisting of proximate and ultimate analyses together calorific value of the parent coals and chars are presented in Table 4. The ash content of the different coal samples ranges from 33.4- 40.4 wt %, the calorific value...

16. Gasification of biomass chars in steam-nitrogen mixture

Energy Technology Data Exchange (ETDEWEB)

Haykiri-Acma, H. [Department of Chemical Engineering, Chemical and Metallurgical Engineering Faculty, Istanbul Technical University, 34469 Maslak, Istanbul (Turkey)]. E-mail: hanzade@itu.edu.tr; Yaman, S. [Department of Chemical Engineering, Chemical and Metallurgical Engineering Faculty, Istanbul Technical University, 34469 Maslak, Istanbul (Turkey); Kucukbayrak, S. [Department of Chemical Engineering, Chemical and Metallurgical Engineering Faculty, Istanbul Technical University, 34469 Maslak, Istanbul (Turkey)

2006-05-15

Some agricultural and waste biomass samples such as sunflower shell, pinecone, rapeseed, cotton refuse and olive refuse were first pyrolyzed in nitrogen, and then, their chars were gasified in a gas mixture of steam and nitrogen. Experiments were performed using the thermogravimetric analysis technique. Pyrolysis of the biomass samples was performed at a heating rate of 20 K/min from ambient to 1273 K in a dynamic nitrogen atmosphere of 40 cm{sup 3} min{sup -1}. The obtained chars were cooled to ambient temperature and then gasified up to 1273 K in a dynamic atmosphere of 40 cm{sup 3} min{sup -1} of a mixture of steam and nitrogen. Derivative thermogravimetric analysis profiles from gasification of the chars were derived, and the mass losses from the chars were interpreted in terms of temperature. It was concluded that gasification characteristics of biomass chars were fairly dependent on the biomass properties such as ash and fixed carbon contents and the constituents present in the ash. Different mechanisms in the three temperature intervals, namely water desorption at lower temperatures, decomposition of hydroxide minerals to oxide minerals and formation of carbon monoxide at medium temperatures and production of hydrogen at high temperatures govern the behavior of the char during the gasification process. The chars from pinecone and sunflower shell could be easily gasified under the mentioned conditions. In order to further raise the conversion yields, long hold times should be applied at high temperatures. However, the chars from rapeseed and olive refuse were not gasified satisfactorily. Low ash content and high fixed carbon content biomass materials are recommended for use in gasification processes when char from pyrolysis at elevated temperatures is used as a feedstock.

17. Development of a catalytic system for gasification of wet biomass

Energy Technology Data Exchange (ETDEWEB)

Elliott, D.C.; Sealock, L.J.; Phelps, M.R.; Neuenschwander, G.G.; Hart, T.R. [Pacific Northwest Lab., Richland, WA (United States)

1993-12-31

A gasification system is under development at Pacific Northwest Laboratory that can be used with high-moisture biomass feedstocks. The system operates at 350{degrees}C and 205 atm using a liquid water phase as the processing medium. Since a pressurized system is used, the wet biomass can be fed as a slurry to the reactor without drying. Through the development of catalysts, a useful processing system has been produced. This paper includes assessment of processing test results of different catalysts. Reactor system results including batch, bench-scale continuous, and engineering-scale processing results are presented to demonstrate the applicability of this catalytic gasification system to biomass. The system has utility both for direct conversion of biomass to fuel gas or as a wastewater cleanup system for treatment of unconverted biomass from bioconversion processes. By the use of this system high conversions of biomass to fuel gas can be achieved. Medium-Btu is the primary product. Potential exists for recovery/recycle of some of the unreacted inorganic components from the biomass in the aqueous byproduct stream.

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

International Nuclear Information System (INIS)

Greil, C.; Hirschfelder, H.

1995-01-01

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. Fast microwave-assisted catalytic gasification of biomass for syngas production and tar removal.

Science.gov (United States)

Xie, Qinglong; Borges, Fernanda Cabral; Cheng, Yanling; Wan, Yiqin; Li, Yun; Lin, Xiangyang; Liu, Yuhuan; Hussain, Fida; Chen, Paul; Ruan, Roger

2014-03-01

In the present study, a microwave-assisted biomass gasification system was developed for syngas production. Three catalysts including Fe, Co and Ni with Al2O3 support were examined and compared for their effects on syngas production and tar removal. Experimental results showed that microwave is an effective heating method for biomass gasification. Ni/Al2O3 was found to be the most effective catalyst for syngas production and tar removal. The gas yield reached above 80% and the composition of tar was the simplest when Ni/Al2O3 catalyst was used. The optimal ratio of catalyst to biomass was determined to be 1:5-1:3. The addition of steam was found to be able to improve the gas production and syngas quality. Results of XRD analyses demonstrated that Ni/Al2O3 catalyst has good stability during gasification process. Finally, a new concept of microwave-assisted dual fluidized bed gasifier was put forward for the first time in this study. Copyright © 2014 Elsevier Ltd. All rights reserved.

20. Biogenic methane from hydrothermal gasification of biomass; Biogenes Methan durch hydrothermale Vergasung von Biomasse

Energy Technology Data Exchange (ETDEWEB)

Schubert, M.; Vogel, F.

2007-09-15

This final report for the Swiss Federal Office of Energy (SFOE) reports on work done in the area of gasification of biomass. The use of dung, manure and sewage sludge as sources of energy is described and discussed. Hydrothermal gasification is proposed as an alternative to conventional gas-phase processes. The aim of the project in this respect is discussed. Here, a catalytic process that demonstrates the gasification of wet biomass to synthetic natural gas (SNG) in a continuously operating plant on a laboratory scale is being looked at. Difficulties encountered in preliminary tests are discussed. Long-term catalyst stability and the installations for the demonstration of the process are discussed, and gasification tests with ethanol are commented on.

1. Gasification of pelletized biomass in a pilot scale downdraft gasifier.

Science.gov (United States)

Simone, Marco; Barontini, Federica; Nicolella, Cristiano; Tognotti, Leonardo

2012-07-01

This work presents a pilot-scale investigation aimed at assessing the feasibility and reliability of biomass pellet gasification. Wood sawdust and sunflower seeds pellets were tested in a 200 kW downdraft gasifier operating with air as gasifying agent. The gasification of pelletized biomass led to rather high and unstable pressure drops, reducing the gasifier productivity and stability. Furthermore the generation of fine residues compromised the operation of wet ash removal systems. On the other hand, good syngas compositions (H(2) 17.2%, N(2) 46.0%, CH(4) 2.5%, CO 21.2%, CO(2) 12.6%, and C(2)H(4) 0.4%), specific gas production (2.2-2.4 N m(3) kg(-1)) and cold gas efficiency (67.7-70.0%) were achieved. For these reasons pelletized biomass should be considered only as complementary fuel in co-gasification with other feedstock. Copyright © 2012 Elsevier Ltd. All rights reserved.

2. Fixed bed gasification for production of industrial fuel gas

Energy Technology Data Exchange (ETDEWEB)

1977-10-01

This report summarizes the results of technical and economic evaluations of six commercially available, fixed-bed coal gasification processes for the production of industrial fuel gas. The study was performed for DOE and is intended to assist industrial companies in exploring the feasibility of producing gaseous fuels for both retrofit and new industrial plant situations. The report includes a technical analysis of the physical configuration, performance capabilities, and commercial experiments to-date for both air-blown and oxygen-blown fixed bed gasifiers. The product gas from these gasifiers is analyzed economically for three different degrees of cleanliness: (1) hot raw gas, (2) dust-, tar-, and oil-free gas, and (3) dust-, tar-, oil-free and desulfurized gas. The evaluations indicate that low-Btu gases produced from fixed bed gasifiers constitute one of the most logical short-term solutions for helping ease the shortage of natural gas for industrial fuel applications because the technology is well-proven and has been utilized on a commercial scale for several decades both in this country and overseas; time from initiation of design to commercial operation is about two years; the technology is not complicated to construct, operate, or maintain; and a reliable supply of product gas can be generated on-site. The advantages and disadvantages of fixed bed gasification technology are listed. The cost of the low Btu gas is estimated at \$2 to \$4 per MM Btu depending on gas purity, cost of coal (\$20 to \$50 per ton) and a number of specified assumptions with respect to financing, reliability, etc. (LTN)

3. 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)

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.

4. Gasification of Nickel-Preloaded Oil Palm Biomass with Air

Directory of Open Access Journals (Sweden)

Syed Shatir A. Syed-Hassan

2016-10-01

5. Fluidized bed gasification of high tonnage sorghum, cotton gin trash and beef cattle manure: Evaluation of synthesis gas production

International Nuclear Information System (INIS)

Maglinao, Amado L.; Capareda, Sergio C.; Nam, Hyungseok

2015-01-01

Highlights: • High tonnage sorghum, cotton gin trash and beef cattle manure were characterized and gasified in a fluidized bed reactor. • Biomass gasification at 730 °C and ER = 0.35 produced synthesis gas with an average energy content of 4.19 MJ Nm −3 . • Synthesis gas heating value and yield were relatively constant at reaction temperatures from 730 °C to 800 °C. • Optimum hydrogen production on HTS gasification was achieved at 780 °C temperature and ER of 0.4. - Abstract: Fluidized bed gasification using high-tonnage sorghum, cotton gin trash and beef cattle manure was performed in a pilot scale bubbling fluidized bed reactor equipped with the necessary feedback control system. Characterization of biomass showed that the high-tonnage sorghum had the highest energy and carbon content of 19.58 MJ kg −1 and 42.29% wt , respectively among the three feed stocks. At 730 °C reaction temperature and equivalence ratio of 0.35, comparable yields of methane, nitrogen and carbon dioxide (within ± 1.4% vol ) were observed in all three feed stocks. The gasification system produced synthesis gas with an average heating value of 4.19 ± 0.09 MJ Nm −3 and an average yield of 1.98 ± 0.1 Nm 3 kg −1 of biomass. Carbon conversion and gasification efficiencies indicated that most of the carbon was converted to gaseous products (85% average ) while 48% average of the energy from the biomass was converted into combustible gas. The production of hydrogen was significantly affected by the biomass used during gasification. The synthesis gas heating value and yield were relatively constant at reaction temperatures from 730 °C to 800 °C. Utilizing high-tonnage sorghum, the optimum hydrogen production during gasification was achieved at a reaction temperature of 780 °C and an equivalence ratio of 0.40.

6. Steam gasification of lignocellulosic residues in a fluidized bed at a small pilot scale; Effect of the type of feedstock

Energy Technology Data Exchange (ETDEWEB)

Herguido, J.; Corella, J.; Gonzalez-Saiz, J. (Chemical and Environmental Engineering Dept., Univ. of Zaragoza, 50009 Zaragoza (ES))

1992-05-01

This paper discusses different biomass materials such as pine sawdust, pine wood chips, cereal straw, and thistles (Cynara cardunculus) from energetic crops gasified with steam in a 15-cm-i.d. fluidized bed reactor. The gas, tar, and char yields, the composition and heating value of the gas produced, and the conversion of carbon have been determined at temperatures between 650 and 780{degrees}C (923-1053 K) for each material. The product distribution varies with the biomass used and the gasification temperature. The differences are very marked for the H{sub 2}, CO, and CO{sub 2} contents in the gas product at low gasification temperatures. These differences decrease when the temperature increases to 780{degrees}C at which point a gas composition similar for all types of biomass tested is obtained by the achievement of equilibrium in the water-gas shift reaction.

7. Recent advances in AFB biomass gasification pilot plant with catalytic reactors in a downstream slip flow

Energy Technology Data Exchange (ETDEWEB)

Aznar, M.P.; Gil, J.; Martin, J.A.; Frances, E.; Olivares, A.; Caballero, M.A.; Perez, P. [Saragossa Univ. (Spain). Dept. of Chemistry and Environment; Corella, J. [Madrid Univ. (Spain)

1996-12-31

A new 3rd generation pilot plant is being used for hot catalytic raw gas cleaning. It is based on a 15 cm. i.d. fluidized bed with biomass throughputs of 400-650 kg/h.m{sup 2}. Gasification is performed using mixtures of steam and oxygen. The produced gas is passed in a slip flow by two reactors in series containing a calcined dolomite and a commercial reforming catalyst. Tars are periodically sampled and analysed after the three reactors. Tar conversions of 99.99 % and a 300 % increase of the hydrogen content in the gas are obtained. (author) (2 refs.)

8. Pre-treatment of oil palm fronds biomass for gasification

Directory of Open Access Journals (Sweden)

Sulaiman Shaharin Anwar

2017-01-01

Full Text Available Oil Palm Fronds (OPF has been proven as one of the potential types of biomass feedstock for power generation. The low ash content and high calorific value are making OPF an attractive source for gasification. The objective of this study is to investigate the effects of pre-treatments of OPF residual on gasification. The pre-treatments included the briquetting process and extensive drying of OPF which are studied separately. In briquetting process, the OPF were mixed with some portions of paper as an additives, leaflets, and water, to form a soupy slurry. The extensive drying of OPF needs to cut down OPF in 4–6 cm particle size and left to dry in the oven at 150°C for 24 hours. Gasification process was carried out at the end of each of the pre-treated processes. It was found that the average gas composition obtained from briquetting process was 8.07%, 2.06%, 0.54%,and 11.02% for CO, H2, CH4, and CO2 respectively. A good composition of syngas was produced from extensive dried OPF, as 16.48%, 4.03%, 0.91%,and 11.15% for CO, H2, CH4, and CO2 contents respectively. It can be concluded that pre-treatments improved the physical characteristics of biomass. The bulk density of biomass can be increased by briquetting but the stability of the structure is depending on the composition of briquette formulation. Furthermore, the stability of gasification process also depended on briquette density, mechanical strength, and formulation.

9. Improved steam gasification of lignocellulosic residues in a fluidized bed with commercial steam reforming catalysts

Energy Technology Data Exchange (ETDEWEB)

Aznar, M.P.; Corella, J.; Delgado, J.; Lahoz, J. (Univ. of Zaragoza (Spain))

1993-01-01

The improved/two-stage steam gasification of biomass or lignocellulosic residues in fluidized bed with steam reforming catalysts placed in a downstream secondary reactor has been studied. Two commercial catalysts, R-67 and RKS-1 from Topsoee, were used at their incipient fluidization conditions. At 720-760 C and space-times of only 0.10-0.20 s, with catalyst sizes under 1.0 mm and with steam/biomass ratios of 1.2-1.6, tar conversions of 99.95% were achieved in the catalytic reactor. In this process, tar and methane in the flue gas can be easily lowered below 5 mg/m[sup 3](NTP) and 0.5 vol %, respectively, without using oxygen. The catalyst deactivation by coke from the tar cracking is the main problem of this process.

10. Biomass gasification for the production of methane

NARCIS (Netherlands)

Nanou, Pavlina

2013-01-01

Biomass is very promising as a sustainable alternative to fossil resources because it is a renewable source that contains carbon, an essential building block for gaseous and liquid fuels. Methane is the main component of natural gas, which is a fuel used for heating, power generation and

11. Biomass Integrated Gasification Combined Cycle for heat and power at ethanol plants

Energy Technology Data Exchange (ETDEWEB)

De Kam, Matthew J.; Vance Morey, R. [Department of Bioproducts and Biosystems Engineering, University of Minnesota, 1390 Eckles Ave, St. Paul, MN 55108 (United States); Tiffany, Douglas G. [Department of Applied Economics, University of Minnesota, 1994 Buford Avenue St. Paul, MN 55108 (United States)

2009-07-15

Biomass Integrated Gasification Combined Cycle (BIGCC) technology can be used to generate process heat and significant amounts of electricity at dry-grind ethanol facilities by utilizing the ethanol process co-products and other biomass sources. These systems can reduce fuel costs for ethanol plants, improve the renewable energy balance of dry-grind ethanol production, and provide reliable renewable electricity for process use and for sale to the local utility. An Aspen Plus model of the dry-grind ethanol process is used as the basis for a subsequent gasification system model. A twin fluidized bed steam gasification configuration based on the SilvaGas process is used to generate synthesis gas. The results show that a dry-grind ethanol facility with a capacity of 190 million liters per year could produce 30.4 MW{sub e} of power while supplying all its process heat needs using ethanol co-products and corn cobs. This configuration results in a three fold improvement in the amount of renewable energy produced per unit of fossil energy used compared to a conventional ethanol production process using natural gas. (author)

12. Thermochemical Biomass Gasification: A Review of the Current Status of the Technology

Directory of Open Access Journals (Sweden)

Ajay Kumar

2009-07-01

Full Text Available A review was conducted on the use of thermochemical biomass gasification for producing biofuels, biopower and chemicals. The upstream processes for gasification are similar to other biomass processing methods. However, challenges remain in the gasification and downstream processing for viable commercial applications. The challenges with gasification are to understand the effects of operating conditions on gasification reactions for reliably predicting and optimizing the product compositions, and for obtaining maximal efficiencies. Product gases can be converted to biofuels and chemicals such as Fischer-Tropsch fuels, green gasoline, hydrogen, dimethyl ether, ethanol, methanol, and higher alcohols. Processes and challenges for these conversions are also summarized.

13. Study of the equilibrium of air-blown gasification of biomass to coal evolution fuels

International Nuclear Information System (INIS)

Biagini, Enrico

2016-01-01

Highlights: • Equilibrium model validated for coals, torrefied/green biomasses, in different gasifiers. • Maps of syngas composition, LHV and CGE for ER = 0–0.6, T = 500–2000 K, EBP = 0.004–0.158. • Effect of unconverted carbon, fuel moisture and overoxidation quantified. • Parameters for the maximum efficiency determined as functions of EBP. • EBP proven to be a good parameter for the quantitative comparison of different fuels. - Abstract: A non-stoichiometric equilibrium model based on the minimization of the Gibbs free energy was used to study the isothermal and adiabatic air-blown gasification of solid fuels on a carbonization curve from fossil (hard/brown coals, peat) to renewable (green biomasses and cellulose) fuels, including torrefied biofuels. The maps of syngas composition, heating value and process efficiency were provided as functions of equivalent ratio (oxygen-to-fuel ratio) in the range 0–0.6, temperature in 500–2000 K, and a fuel parameter, which allowed different cases to be quantitatively compared. The effect of fuel moisture, unconverted carbon and conditions to limit the tar formation was also studied. Cold gas efficiency >0.75 can be achieved for coals at high temperature, using entrained beds (which give low unconverted carbon), and improved by moisture/added steam. The bigger efficiency of green biomasses is only potential, as the practical limits (high temperature required to limit tar formation, moisture content and unconverted carbon in small gasifiers) strongly reduce the gasification performance. Torrefied biomasses (and plastics having an intermediate fuel parameter between coals and green biomasses) can attain high efficiency also in real conditions. The results shown in this work can be useful to evaluate the most promising feedstock (depending on its composition and possible pre-treatment/upgrading), define the operating conditions for maximizing the syngas heating value or the global efficiency, assess the

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

International Nuclear Information System (INIS)

Sarker, Shiplu; Arauzo, Jesús; Nielsen, Henrik Kofoed

2015-01-01

Highlights: • Alfalfa and wheat straw pellets were gasified in a lab-scale fluid-bed reactor. • ER varied between 0.20 and 0.35 at which several parameters investigated. • ER = 0.35 was found optimum for alfalfa at which process performance improved. • ER = 0.30 revealed optimum for wheat straw at which gasification was effective. - Abstract: Small scale air-blown fluidized bed gasification of alfalfa and wheat straw pellets were conducted for semi-continuous solid feeding and range of operating conditions varied due to the modifications in equivalence ratio (ER) (0.20–0.35) achieved both by varying solid and air input. Alfalfa pellets displayed an improvement in several gasification variables such as gas lower heating value (∼4.1 MJ/Nm 3 ), specific gas yield (1.66 Nm 3 /kg), cold gas efficiency (∼42%) and carbon conversion efficiency (∼72%) as ER maximized to 0.35 which was found optimum for this feedstock for the present course of experiments. Gasification parameters of wheat straw pellets on the other hand were characterized by a great degree of variation as the ER progressively increased. The optimum performance of this biomass was likely to achieve at ER = 0.30 when gas lower heating value and cold gas efficiency maximized to ∼4 MJ/Nm 3 and ∼37% respectively. Moreover, a substantial drop in tar yield (58.7 g/Nm 3 ) at this ER was also indicative to the optimal thermal conversion at this point of operation. Overall, both the feedstocks presented promising alternatives for utilization into the small-scale fluidized bed gasification which is increasingly emerging as a sustainable solution towards processing lignocellulosic biomass

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

Energy Technology Data Exchange (ETDEWEB)

Archie Robertson

2003-10-29

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

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

Energy Technology Data Exchange (ETDEWEB)

Unknown

2003-01-30

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

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

Energy Technology Data Exchange (ETDEWEB)

Archie Robertson

2003-07-23

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

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

Energy Technology Data Exchange (ETDEWEB)

A. Robertson

2003-12-31

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

19. Fluidized bed gasification of waste-derived fuels.

Science.gov (United States)

Arena, Umberto; Zaccariello, Lucio; Mastellone, Maria Laura

2010-07-01

Five alternative waste-derived fuels obtained from municipal solid waste and different post-consumer packaging were fed in a pilot-scale bubbling fluidized bed gasifier, having a maximum feeding capacity of 100 kg/h. The experimental runs utilized beds of natural olivine, quartz sand or dolomite, fluidized by air, and were carried out under various values of equivalence ratio. The process resulted technically feasible with all the materials tested. The olivine, a neo-silicate of Fe and Mg with an olive-green colour, has proven to be a good candidate to act as a bed catalyst for tar removal during gasification of polyolefin plastic wastes. Thanks to its catalytic activity it is possible to obtain very high fractions of hydrogen in the syngas (between 20% and 30%), even using air as the gasifying agent, i.e. in the most favourable economical conditions and with the simplest plant and reactor configuration. The catalytic activity of olivine was instead reduced or completely inhibited when waste-derived fuels from municipal solid wastes and aggregates of different post-consumer plastic packagings were fed. Anyhow, these materials have given acceptable performance, yielding a syngas of sufficient quality for energy applications after an adequate downstream cleaning. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

20. Commercial steam reforming catalysts to improve biomass gasification with steam-oxygen mixtures. 2: Catalytic tar removal

Energy Technology Data Exchange (ETDEWEB)

Aznar, M.P.; Caballero, M.A.; Gil, J.; Martin, J.A. [Univ. of Saragossa (Spain). Chemical and Environmental Engineering Dept.; Corella, J. [Univ. Complutense of Madrid (Spain). Chemical Engineering Dept.

1998-07-01

Eight different commercial catalysts, nickel based, for steam reforming of naphthas and of natural gas are tested in biomass gasification for hot gas cleanup and conditioning. They were manufactured by BASF AG, ICI-Katalco, UCI, and Haldor Topsoee a/s. The catalysts were tested in a slip flow after a biomass gasifier of fluidized bed type at small pilot-plant scale (10--20 kg of biomass/h). The gasifying agent used is steam-oxygen mixtures. A guard bed containing a calcined dolomite is used to decrease the tar content in the gas at the inlet of the catalytic bed. Main variables studied are catalyst type, bed temperature, H{sub 2}O + O{sub 2} to biomass feed ratio, and time-on-stream. All catalysts for reforming of naphthas show to be very active and useful for tar removal and gas conditioning (in biomass gasification). 98% tar removal is easily obtained with space velocities of 14,000 h{sup {minus}1} (n.c.). No catalysts deactivation is found in 48 h-on-stream tests when the catalyst temperature is relatively high (780--830 C). Using a simple first-order kinetic model for the overall tar removal reaction, apparent energies of activation (of around 58 kJ/mol) and preexponential factors are obtained for the most active catalysts.

1. Air gasification of biogas-derived digestate in a downdraft fixed bed gasifier.

Science.gov (United States)

Chen, Guanyi; Guo, Xiang; Cheng, Zhanjun; Yan, Beibei; Dan, Zeng; Ma, Wenchao

2017-11-01

Digestate is a byproduct from biomass anaerobic digestion process. Gasification of dried digestate to produce gasesous product might be a promising route. In this work, air gasification of digestate with high ash content was performed in a downdraft fixed bed gasifier at temperature varying from 600°C to 800°C and air equivalence ratio (ER) ranging from 0.25 to 0.30. The ash melting properties were firstly detected by the Intelligent Ash Melting Point Test, and the by-products (biochar and ash) were analyzed. The results showed that no ash slagging was observed and therefore it is feasible to operate digestate gasification under 800°C and ER ranging from 0.25 to 0.30. High temperature favored gas production, 800°C is proposed for digestate gasification in the present study. ER with a medium value improved gas quality and cold gas efficiency (CGE), and the optimal LHV of 4.78MJ/Nm 3 and CGE of 67.01% were obtained with ER of 0.28. High ER favored the increase of gas yield and decrease of tar concentration, and the optimal gas yield of 2.15 Nm 3 /kg and tar concentration of 1.61g/Nm 3 were achieved with ER of 0.30. Improved molar ratio of H 2 /CO varying from 1.03 to 1.08 was obtained at 800°C, indicating gaseous product has the potential for chemical synthesis processes (1

2. Transient behavior of devolatilization and char reaction during steam gasification of biomass.

Science.gov (United States)

Moon, Jihong; Lee, Jeungwoo; Lee, Uendo; Hwang, Jungho

2013-04-01

Steam gasification of biomass is a promising method for producing high quality syngas for polygeneration. During the steam gasification, devolatilization and char reaction are key steps of syngas production and the contributions of the two reactions are highly related to gasification conditions. In this study, the transient characteristics of devolatilization and char reaction in biomass steam gasification were investigated by monitoring cumulative gas production and composition changes in terms of reaction temperature and S/B ratio. Contribution of each reaction stage on the product gas yield was studied in detail. The results provide important insight for understanding the complex nature of biomass gasification and will guide future improvements to the biomass gasification process. Copyright © 2013 Elsevier Ltd. All rights reserved.

3. Pilot scale testing of biomass feedstocks for use in gasification/gas turbine based power generation systems

Energy Technology Data Exchange (ETDEWEB)

Najewicz, D.J.; Furman, A.H. [General Electric Corporate Research and Development Center, Schenectady, NY (United States)

1993-12-31

A biomass gasification pilot program was performed at the GE Corporate Research and Development Center using two types of biomass feedstock. The object of the testing was to determine the properties of biomass product gas and its` suitability as a fuel for gas turbine based power generation cycles. The test program was sponsored by the State of Vermont, the US Environmental Protection Agency, the US Department of Energy and Winrock International/US Agency for International Development. Gasification of bagasse and wood chip feedstock was performed at a feed rate of approximately one ton per hour, using the Ge pressurized fixed bed gasifier and a single stage of cyclone particulate removal, operating at a temperature of 1,000 F. Both biomass feedstocks were found to gasify easily, and gasification capacity was limited by volumetric capacity of the fuel feed equipment. The biomass product gas was analyzed for chemical composition, particulate loading, fuel bound nitrogen levels, sulfur and alkali metal content. The results of the testing indicated the combustion characteristics of the biomass product gas are compatible with gas turbine combustor requirements. However, the particulate removal performance of the pilot facility single stage cyclone was found to be inadequate to meet turbine particulate contamination specifications. In addition, alkali metals found in biomass based fuels, which are known to cause corrosion of high temperature gas turbine components, were found to exceed allowable levels in the fuel gas. These alkali metal compounds are found in the particulate matter (at 1000 F) carried over from the gasifier, thus improved particulate removal technology, designed specifically for biomass particulate characteristics could meet the turbine requirements for both particulate and alkali loading. The paper will present the results of the biomass gasification testing and discuss the development needs in the area of gas clean-up and turbine combustion.

4. Fluidised bed gasification of high-ash South African coals: An experimental and modelling study

CSIR Research Space (South Africa)

Engelbrecht, AS

2011-11-01

Full Text Available The gasification of two high-ash coals were studied using a pilot scale fluidised bed gasifier using oxygen enrich air and steam as the gasification agents. The results of the tests show that the fixed carbon conversion and calorific value increases...

5. Fluidised bed gasification of South African coals – experimental results and process integration

CSIR Research Space (South Africa)

Engelbrecht, A

2011-06-01

Full Text Available high-ash coal from the Waterberg coalfield was tested in a bubbling fluidised bed gasifier at the CSIR using various gasification agents and operating conditions. The results of the tests show that when air and steam are used as the gasification agents...

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

DEFF Research Database (Denmark)

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

2012-01-01

on soil nutrient levels or on crop biomass. We conclude from the results of this study, that—depending on the feedstock used—ashes from LT-CFB gasification of plant biomass can be used to replace mineral fertilizers if they are applied according to their nutrient content, the crop demand, and soil......Recycling of residual products of bioenergy conversion processes is important for adding value to the technologies and as a potential beneficial soil fertility amendment. In this study, two different ash materials originating from low temperature circulating fluidized bed (LT-CFB) gasification...... of either wheat straw (SA) or residue fibers mainly from citrus peels (CP) were tested regarding their potential to be used as fertilizer on agricultural soils. A soil incubation study, a greenhouse experiment with barley and faba bean, and an accompanying outdoor experiment with maize were carried out...

7. Thermal Plasma Gasification of Biomass for Fuel Gas Production

Czech Academy of Sciences Publication Activity Database

Hrabovský, Milan; Hlína, Michal; Konrád, Miloš; Kopecký, Vladimír; Kavka, Tetyana; Chumak, Oleksiy; Mašláni, Alan

2009-01-01

Roč. 13, č. 3-4 (2009), s. 299-313 ISSN 1093-3611 R&D Projects: GA ČR GA202/08/1084 Institutional research plan: CEZ:AV0Z20430508 Keywords : Thermal plasma * plasma gasification * syngas * biomass Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.333, year: 2009 http://www.begellhouse.com/journals/57d172397126f956,5cbc272245f24168,0ac09d02537962cf.html

8. Vision of the U.S. biofuel future: a case for hydrogen-enriched biomass gasification

Science.gov (United States)

Mark A. Dietenberger; Mark Anderson

2007-01-01

Researchers at the Forest Product Laboratory (FPL) and the University of Wisconsin-Madison (UW) envision a future for biofuels based on biomass gasification with hydrogen enrichment. Synergisms between hydrogen production and biomass gasification technologies will be necessary to avoid being marginalized in the biofuel marketplace. Five feasible engineering solutions...

9. System model for gasification of biomass model compounds in supercritical water – a thermodynamic analysis

NARCIS (Netherlands)

Withag, Jan A.M.; Smeets, Jules R.; Bramer, Eduard A.; Brem, Gerrit

2012-01-01

This article presents a system model for the process of gasification of biomass model compounds in supercritical water. Supercritical water gasification of wet biomass (water content of 70 wt% or more) has as the main advantage that conversion may take place without the costly drying step. The

10. Biomass Gasification Research and Development Project

Energy Technology Data Exchange (ETDEWEB)

Ahring, Birgitte K. [Washington State Univ., Pullman, WA (United States)

2014-07-22

The overall objective of the BioChemCat project was to demonstrate the feasibility of using Advanced Wet Oxidation Steam-Explosion (AWEx) process to open and solubilize lignocellulosic biomass (LBM) coupled to an innovative mixed culture fermentation technology capable of producing a wide range of volatile fatty acids (VFAs) from all sugars present in LBM. The VFAs will then be separated and converted to hydrocarbon biofuel through catalytic upgrading. By continuously removing VFAs as they are produced (extractive fermentation), we were able to recover the VFAs while both eliminating the need for pH adjustment and increasing the fermentation productivity. The recovered VFAs were then esterified and upgraded to hydrocarbon fuels through a parallel series of hydrogenolysis/decarboxylation and dehydration reactions. We also demonstrated that a portion of the residual lignin fraction was solubilized and converted into VFAs, also improving the yields of VFAs. The remaining lignin fraction was then shown to be available (after dewatering and drying) for use as a lignin-enriched fuel pellet or as a feedstock for further processing.

11. Roadmap for the commercialisation of biomass gasification. A critical evaluation, tips, questions and pitfalls

International Nuclear Information System (INIS)

Huisman, G.H.

2000-10-01

Biomass has the potential to be a major replacement of fossil fuels. The world wide availability of biomass is considerable but it is not always in balance with the anticipated consumption. Biomass (wood) has the disadvantage that it has a low energy density and transport costs are, therefore, relatively high. Combustion, being a well-developed technology with many references, is the obvious choice for conversion technology. On the scale that biomass plants are usually constructed, however, the overall efficiency of the combustion system is low. Gasification has the advantage that solid fuel is converted into gaseous fuel which can be used in IC (internal combustion) engines or combined (gas and steam turbine) cycles with high efficiency. Even on a very small scale (several hundred kWe) a biomass-driven IC engine can have an efficiency of around 25%. Gasification has not yet advanced to the stage that it can serve as a reliable conversion technology for supplying electric power to industry or to the national grid. This may be possible on paper but in practice the market needs to be convinced by the success of plants in full operation. The first generation of plants, now under construction, or in operation, have to demonstrate the technology and provide confidence for future developments. Fixed bed gasification in combination with IC engines is more appropriate for small units. The development in micropower units is of particular interest. This development has been initiated for natural gas-fuelled units supplying power and heat to households, apartment blocks or offices. Once the fuel handling problems have been overcome and the units are more reliable and easier to operate, this could be a market with ample cost savings on the basis of mass production. Fluidised bed gasification, integrated with a combined cycle, is probably better suited to larger units, above 10 MWe. After experience has been obtained with units at an atmospheric pressure, the increase of the

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

Science.gov (United States)

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

2014-05-01

Gasification reactivities of six different carbonaceous material chars with CO2 were determined by a Thermogravimetric Analyzer (TGA). Gasification reactivities of biomass chars are higher than those of coke and coal chars. In addition, physical structures and chemical components of these chars were systematically tested. It is found that the crystalline structure is an important factor to evaluate gasification reactivities of different chars and the crystalline structures of biomass chars are less order than those of coke and coal chars. Moreover, initial gasification rates of these chars were measured at high temperatures and with relatively large particle sizes. The method of calculating the effectiveness factor η was used to quantify the effect of pore diffusion on gasification. The results show that differences in pore diffusion effects among gasification with various chars are prominent and can be attributed to different intrinsic gasification reactivities and physical characteristics of different chars. Copyright © 2014 Elsevier Ltd. All rights reserved.

13. Ab initio calculations and kinetic modeling of thermal conversion of methyl chloride: implications for gasification of biomass.

Science.gov (United States)

Singla, Mallika; Rasmussen, Morten Lund; Hashemi, Hamid; Wu, Hao; Glarborg, Peter; Pelucchi, Matteo; Faravelli, Tiziano; Marshall, Paul

2018-01-24

Limitations in current hot gas cleaning methods for chlorine species from biomass gasification may be a challenge for end use such as gas turbines, engines, and fuel cells, all requiring very low levels of chlorine. During devolatilization of biomass, chlorine is released partly as methyl chloride. In the present work, the thermal conversion of CH 3 Cl under gasification conditions was investigated. A detailed chemical kinetic model for pyrolysis and oxidation of methyl chloride was developed and validated against selected experimental data from the literature. Key reactions of CH 2 Cl with O 2 and C 2 H 4 for which data are scarce were studied by ab initio methods. The model was used to analyze the fate of methyl chloride in gasification processes. The results indicate that CH 3 Cl emissions will be negligible for most gasification technologies, but could be a concern for fluidized bed gasifiers, in particular in low-temperature gasification. The present work illustrates how ab initio theory and chemical kinetic modeling can help to resolve emission issues for thermal processes in industrial scale.

14. Gasification Characteristics of Coal/Biomass Mixed Fuels

Energy Technology Data Exchange (ETDEWEB)

Mitchell, Reginald [Stanford Univ., CA (United States). Mechanical Engineering Dept.

2014-09-01

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

15. Development of a pressurized fluidized-bed biomass gsifier to produce substitute fuels

Science.gov (United States)

Babu, S. P.; Onischak, M.; Kosowski, G.

The Institute of Gas technology (IGT) is conducting a program to convert forest and crop residues to substitute fuel in a pressurized fluidized-bed biomass gasifier. The process is designed for operation at pressures up to 2.17 MPa (315 psia) and temperatures up to 1255 K (1800 F). Various goals for synthesis or fuel gas processes are being pursued to develop an efficient process. Some of these goals are to maximize the throughput, the amount, and the quality of the gas, while minimizing both the amount of the feedstock preparation needed and the formation of condensible compounds that require by-product disposal and process wastewater treatment. The process development results obtained from fluidization biomass devolatilization, and char gasification studies were used to design a 30/5-cm (12-inch) ID adiabatic fluidized-bed gasification process development unit (PDU), capable of handling up to 455 kg (1000 lb) of biomass per hour.

16. Performance of different dolomites on hot raw gas cleaning from biomass gasification with air

Energy Technology Data Exchange (ETDEWEB)

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

1997-09-01

Calcined dolomites (CaO-MgO) from four different quarries have been tested for the upgrading of the hot raw gas from a fluidized bed gasifier of biomass with air. These calcined dolomites have big macropores (900--4,000 {angstrom}) and low (3.8--12 m{sup 2}/g) BET surface areas. They have been tested in a fixed bed of 6 cm i.d. downstream from the air-blown biomass gasifier. The change in gas composition (contents in H{sub 2}, CO, CO{sub 2}, CH{sub 4}, {hor_ellipsis}), tar content, gas heating value, etc., has been studied in different temperatures (780--920 C) as well as space-times for the gas in the bed (0.03--0.10 kg{center_dot}h/m{sup 3}) and the type of dolomite. Increasing the equivalence ratio used in the gasifier and decreasing the H/C ratio of the gas increases the refractoriness of the tars to be eliminated by the calcined dolomite. Activation energies (100 {+-} 20 kJ/mol) and preexponential factors for the overall tar elimination reaction have been calculated for the different dolomites under realistic conditions. The activity of the dolomite for tar elimination can increase by 20% on increasing its pore diameter or its Fe{sub 2}O{sub 3} content. Comparison of results with similar ones obtained in biomass gasification with steam is also presented.

17. Biomass Gasification for Power Generation Internal Combustion Engines. Process Efficiency

International Nuclear Information System (INIS)

Lesme-Jaén, René; Garcia-Faure, Luis; Oliva-Ruiz, Luis; Pajarín-Rodríguez, Juan; Revilla-Suarez, Dennis

2016-01-01

Biomass is a renewable energy sources worldwide greater prospects for its potential and its lower environmental impact compared to fossil fuels. By different processes and energy conversion technologies is possible to obtain solid, liquid and gaseous fuels from any biomass.In this paper the evaluation of thermal and overall efficiency of the gasification of Integral Forestry Company Santiago de Cuba is presented, designed to electricity generation from waste forest industry. The gasifier is a downdraft reactor, COMBO-80 model of Indian manufacturing and motor (diesel) model Leyland modified to work with producer gas. The evaluation was conducted at different loads (electric power generated) of the motor from experimental measurements of flow and composition of gas supplied to the engine. The results show that the motor operates with a thermal efficiency in the range of 20-32% with an overall efficiency between 12-25 %. (author)

18. Biomass gasification in Europe - status and perspectives; Vergasung von Biomasse in Europa - Stand und Perspektiven

Energy Technology Data Exchange (ETDEWEB)

Dinkelbach, L.; Kaltschmitt, M. [Stuttgart Univ. (Germany). Inst. fuer Energiewirtschaft und Rationelle Energieanwendung (IER)

1996-12-31

Gasification of biomass is a promising option, especially in the fields of waste management and power generation, but there are considerable economic and technical problems that must be solved first. A critical analysis of biomass gasification in Europe today shows that this technology is not marketable today and cannot contribute to environmentally acceptable power supply on a short-term basis. (orig) [Deutsch] Von allen Moeglichkeiten einer energetischen Nutzung von Biomasse stellt die Technik der Vergasung insbesondere in den Bereichen Abfallentsorgung und Stromerzeugung eine vielversprechende Option dar. Einer weiteren Verbreitung dieser Technik stehen allerdings erhebliche wirtschaftliche und technische Probleme entgegen. Die kritische Analyse der derzeitigen Gegebenheiten der Biomassevergasung in Europa fuehrt zu dem Schluss, dass diese Technik noch nicht unmittelbar vor der Mrkteinfuehrung steht und somit kurzfristig keinen merklichen Beitrag zu einer umwelt- und klimavertraeglicheren Energieversorgung in Europa leisten kann. (orig)

19. Performance of a pilot-scale, steam-blown, pressurized fluidized bed biomass gasifier

Science.gov (United States)

Sweeney, Daniel Joseph

With the discovery of vast fossil resources, and the subsequent development of the fossil fuel and petrochemical industry, the role of biomass-based products has declined. However, concerns about the finite and decreasing amount of fossil and mineral resources, in addition to health and climate impacts of fossil resource use, have elevated interest in innovative methods for converting renewable biomass resources into products that fit our modern lifestyle. Thermal conversion through gasification is an appealing method for utilizing biomass due to its operability using a wide variety of feedstocks at a wide range of scales, the product has a variety of uses (e.g., transportation fuel production, electricity production, chemicals synthesis), and in many cases, results in significantly lower greenhouse gas emissions. In spite of the advantages of gasification, several technical hurdles have hindered its commercial development. A number of studies have focused on laboratory-scale and atmospheric biomass gasification. However, few studies have reported on pilot-scale, woody biomass gasification under pressurized conditions. The purpose of this research is an assessment of the performance of a pilot-scale, steam-blown, pressurized fluidized bed biomass gasifier. The 200 kWth fluidized bed gasifier is capable of operation using solid feedstocks at feedrates up to 65 lb/hr, bed temperatures up to 1600°F, and pressures up to 8 atm. Gasifier performance was assessed under various temperatures, pressure, and feedstock (untreated woody biomass, dark and medium torrefied biomass) conditions by measuring product gas yield and composition, residue (e.g., tar and char) production, and mass and energy conversion efficiencies. Elevated temperature and pressure, and feedstock pretreatment were shown to have a significant influence on gasifier operability, tar production, carbon conversion, and process efficiency. High-pressure and temperature gasification of dark torrefied biomass

20. Wind Generator & Biomass No-draft Gasification Hybrid

Science.gov (United States)

Hein, Matthew R.

The premise of this research is that underutilized but vast intermittent renewable energy resources, such as wind, can become more market competitive by coupling with storable renewable energy sources, like biomass; thereby creating a firm capacity resource. Specifically, the Midwest state of South Dakota has immense wind energy potential that is not used because of economic and logistic barriers of electrical transmission or storage. Coupling the state's intermittent wind resource with another of the state's energy resources, cellulosic non-food biomass, by using a wind generator and no-draft biomass gasification hybrid system will result in a energy source that is both firm and storable. The average energy content of common biomass feedstock was determined, 14.8 MJ/kg (7.153 Btu/lb), along with the assumed typical biomass conversion efficiency of the no-draft gasifier, 65%, so that an average electrical energy round trip efficiency (RTE) of 214% can be expected (i.e. One unit of wind electrical energy can produce 2.14 kWh of electrical energy stored as syngas.) from a wind generator and no-draft biomass gasification system. Wind characteristics are site specific so this analysis utilizes a synthetic wind resource to represent a statistically sound gross representation of South Dakota's wind regime based on data from the Wind Resource Assessment Network (WRAN) locations. A synthetic wind turbine generated from common wind turbine power curves and scaled to 1-MW rated capacity was utilized for this analysis in order to remove equipment bias from the results. A standard 8,760-hour BIN Analysis model was constructed within HOMER, powerful simulation software developed by the National Renewable Energy Laboratory (NREL) to model the performance of renewable power systems. It was found that the optimum configuration on a per-megawatt-transmitted basis required a wind generator (wind farm) rated capacity of 3-MW with an anticipated annual biomass feedstock of 26,132 GJ

1. Gasification behavior of coal and woody biomass: Validation and parametrical study

International Nuclear Information System (INIS)

Adeyemi, Idowu; Janajreh, Isam; Arink, Thomas; Ghenai, Chaouki

2017-01-01

Highlights: • Numerical modeling and experimental diagnostics of entrained flow gasification. • Obtain the effect of gasification of Kentucky coal and wood waste. • Obtain the effect of equivalence ratio, pressure and temperature. • Kentucky coal produced higher gasification efficiency as compared to wood. • The gasification efficiency most sensitive to equivalence ratio. - Abstract: The entrained flow gasification of two feedstocks (Kentucky coal and woody biomass) have been investigated in this study both numerically and experimentally. Previously, there had been no study that investigated the centerline parameters during the experimental gasification of Kentucky coal and biomass utilizing drop tube reactor (DTR). These high quality centerline experiments provide enough data for high fidelity model development and used for an innovative gasifier design. This work investigates the gasification behavior of Kentucky coal and wood waste under different gasification parameters including equivalence ratio, pressure and temperature. The experimental study was conducted in the air-blown atmospheric DTR experimental facility at the Waste-2-Energy Laboratory at Masdar Institute. The measured centerline temperature, exit gas composition, and SEM images was obtained for model validation and to gain better insight into the gasification of the two different feedstock particles. The Lagrangian–Eulerian based numerical model predicted the experimental results reasonably. The effect of the fuel type on the gas composition along the centerline of the gasifier indicated that Kentucky coal attained higher gasification efficiency when compared to that of wood waste. Moreover, the gasification efficiency was most sensitive to the equivalence ratio.

2. Simulation of Steam Gasification in a Fluidized Bed Reactor with Energy Self-Sufficient Condition

Directory of Open Access Journals (Sweden)

Ajaree Suwatthikul

2017-03-01

Full Text Available The biomass gasification process is widely accepted as a popular technology to produce fuel for the application in gas turbines and Organic Rankine Cycle (ORC. Chemical reactions of this process can be separated into three reaction zones: pyrolysis, combustion, and reduction. In this study, sensitivity analysis with respect to three input parameters (gasification temperature, equivalence ratio, and steam-to-biomass ratio has been carried out to achieve energy self-sufficient conditions in a steam gasification process under the criteria that the carbon conversion efficiency must be more than 70%, and carbon dioxide gas is lower than 20%. Simulation models of the steam gasification process have been carried out by ASPEN Plus and validated with both experimental data and simulation results from Nikoo & Mahinpey (2008. Gasification temperature of 911 °C, equivalence ratio of 0.18, and a steam-to-biomass ratio of 1.78, are considered as an optimal operation point to achieve energy self-sufficient condition. This operating point gives the maximum of carbon conversion efficiency at 91.03%, and carbon dioxide gas at 15.18 volumetric percentages. In this study, life cycle assessment (LCA is included to compare the environmental performance of conventional and energy self-sufficient gasification for steam biomass gasification.

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

Directory of Open Access Journals (Sweden)

Thanasit Wongsiriamnuay

2013-01-01

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

4. 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.

5. 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......, and oxygen enrichment] on producer gas. The model predicts the behavior of different kinds of biomass and becomes a useful tool to simulate the biomass gasification process by allowing its integration in complete energy supply systems, such as co-generation plants....

6. OPERATING SPECIFICATIONS OF CATALYTIC CLEANING OF GAS FROM BIOMASS GASIFICATION

Directory of Open Access Journals (Sweden)

Martin Lisý

2015-12-01

Full Text Available The paper focuses on the theoretical description of the cleaning of syngas from biomass and waste gasification using catalytic methods, and on the verification of the theory through experiments. The main obstruction to using syngas from fluid gasification of organic matter is the presence of various high-boiling point hydrocarbons (i.e., tar in the gas. The elimination of tar from the gas is a key factor in subsequent use of the gas in other technologies for cogeneration of electrical energy and heat. The application of a natural or artificial catalyst for catalytic destruction of tar is one of the methods of secondary elimination of tar from syngas. In our experiments, we used a natural catalyst (dolomite or calcium magnesium carbonate from Horní Lánov with great mechanical and catalytic properties, suitable for our purposes. The advantages of natural catalysts in contrast to artificial catalysts include their availability, low purchase prices and higher resilience to the so-called catalyst poison. Natural calcium catalysts may also capture undesired compounds of sulphure and chlorine. Our paper presents a theoretical description and analysis of catalytic destruction of tar into combustible gas components, and of the impact of dolomite calcination on its efficiency. The efficiency of the technology is verified in laboratories. The facility used for verification was a 150 kW pilot gasification unit with a laboratory catalytic filter. The efficiency of tar elimination reached 99.5%, the tar concentration complied with limits for use of the gas in combustion engines, and the tar content reached approximately 35 mg/mn3. The results of the measurements conducted in laboratories helped us design a pilot technology for catalytic gas cleaning.

7. Dairy Biomass-Wyoming Coal Blends Fixed Gasification Using Air-Steam for Partial Oxidation

Directory of Open Access Journals (Sweden)

Gerardo Gordillo

2012-01-01

Full Text Available Concentrated animal feeding operations such as dairies produce a large amount of manure, termed as dairy biomass (DB, which could serve as renewable feedstock for thermal gasification. DB is a low-quality fuel compared to fossil fuels, and hence the product gases have lower heat content; however, the quality of gases can be improved by blending with coals. This paper deals with air-steam fixed-bed counterflow gasification of dairy biomass-Wyoming coal blend (DBWC. The effects of equivalence ratio (1.6<Φ<6.4 and steam-to-fuel ratio (0.4

8. Effect of reactions in small eddies on biomass gasification with eddy dissipation concept - Sub-grid scale reaction model.

Science.gov (United States)

Chen, Juhui; Yin, Weijie; Wang, Shuai; Meng, Cheng; Li, Jiuru; Qin, Bai; Yu, Guangbin

2016-07-01

Large-eddy simulation (LES) approach is used for gas turbulence, and eddy dissipation concept (EDC)-sub-grid scale (SGS) reaction model is employed for reactions in small eddies. The simulated gas molar fractions are in better agreement with experimental data with EDC-SGS reaction model. The effect of reactions in small eddies on biomass gasification is emphatically analyzed with EDC-SGS reaction model. The distributions of the SGS reaction rates which represent the reactions in small eddies with particles concentration and temperature are analyzed. The distributions of SGS reaction rates have the similar trend with those of total reactions rates and the values account for about 15% of the total reactions rates. The heterogeneous reaction rates with EDC-SGS reaction model are also improved during the biomass gasification process in bubbling fluidized bed. Copyright © 2016 Elsevier Ltd. All rights reserved.

9. PFB air gasification of biomass. Investigation of product formation and problematic issues related to ammonia, tar and alkali

Energy Technology Data Exchange (ETDEWEB)

2000-09-01

Fluidised bed thermal gasification of biomass is an effective route that results in 100 % conversion of the fuel. In contrast to chemical, enzymatic or anaerobic methods of biomass treatment, the thermal conversion leaves no contaminated residue after the process. The product gas evolved within thermal conversion can be used in several applications such as: fuel for gas turbines, combustion engines and fuel cells, and raw material for production of chemicals and synthetic liquid fuels. This thesis treats a part of the experimental data from two different gasifiers: a 90 kW{sub th} pressurised fluidised bubbling bed gasifier at Lund University and a 18 MW{sub th} circulating fluidised bed gasifier integrated with gas turbine (IGCC) in Vaernamo. A series of parallel and consecutive chemical reactions is involved in thermal gasification, giving origin to formation of a variety of products. These products can be classified within three major groups: gases, tars and oils, and char. The proportion of these categories of species in the final product is a matter of the gasifier design and the process parameters. The thesis addresses the technical and theoretical aspects of the biomass thermochemical conversion and presents a new approach in describing the gasification reactions. There is an evidence of fuel effect on the characteristics of the final products: a mixture of plastic waste (polyethylene) and biomass results in higher concentration of linear hydrocarbons in the gas than gasification of pure biomass. Mixing the biomass with textile waste (containing aromatic structure) results in a high degree of formation of aromatic compounds and light tars. Three topic questions within biomass gasification, namely: tar, NO{sub x} and alkali are discussed in the thesis. The experimental results show that gasification at high ER or high temperature decreases the total amount of the tars and simultaneously reduces the contents of the oxygenated and alkyl-substituted poly

10. 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)

11. Gasification of biomass - principles and technical alternatives; Vergasung von Biomassen - Prinzipien und technische Moeglichkeiten

Energy Technology Data Exchange (ETDEWEB)

Klose, E. [Technische Univ. Bergakademie, Freiberg (Germany)

1996-12-31

The technical principles of gasification are outlined, and a number of biomass gasification processes are presented and compared with the coal gasification process. On the basis of the knowledge gained in coal gasification, it will be easy to carry out the development work still required on small-scale biomass gasification systems in cooperation with the gas users. (orig) [Deutsch] Das technische Prinzip derVergasung und verschiedene Verfahrensweisen bei der Vergasung von Biomasse werden vorgestellt und mit der Kohlevergasung verglichen. Auf der Grundlage der technischen Erkenntnisse bei der Kohlevergasung einschliesslich der vor- und nachgeschalteten Prozessstufen sind die noch notwendigen verfahrens- und apparatetechnischen Entwicklungsarbeiten fuer vorwiegend kleine Anlagen in Zusammenarbeit mit den Gasnutzern durchfuehrbar. (orig)

12. 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

13. Release of chlorine from biomass at gasification conditions

International Nuclear Information System (INIS)

Bjoerkman, E.; Stroemberg, B.

1997-05-01

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 O 2 , H 2 O and CO 2 had negligible effect on the chlorine release at temperatures under 700 deg C. At temperatures above 800 deg C the reactivity towards CO 2 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

14. Preliminary studies on the treatment of wastewater from biomass gasification.

Science.gov (United States)

Muzyka, Roksana; Chrubasik, Maciej; Stelmach, Sławomir; Sajdak, Marcin

2015-10-01

This paper presents completed research on the purification of undiluted raw water and organic condensates obtained in biomass thermal conversion processes such as gasification, which are rarely addressed in published studies. However, similar studies involving the characterization and purification of aqueous solutions obtained from process gas treatment after the gasification of biomass are available. Condensation of water-organic condensate from process gas helps to reduce the amount of water required by the purification process and the cost of the process technology and water consumption. Oil scrubbers can be used in this case instead of water scrubbers. In this case, the obtained condensate must be subjected to purification processes. This paper presents the results of our research, possible methods of treatment (chemical and biological methods), and the approximate cost of the reagents required for the purification of condensate for specific assumed degrees of purification. The best results from the chemical purification using the Fenton method were obtained with the ratio V(H2O2)/V(cond.) = 6.0 and the ratio V(H2O2)/Fe = 0.0375. To prevent precipitation of ferric hydroxide, this value can be reduced 20-fold, which reduces the total degree of purification to 90%. The cost of almost complete cleaning of tested condensates was calculated to be approximately 2000 USD per/m(3). This cost can be reduced by a factor of approximately four assuming 100% cleaning for 2-furaldehyde, furfuryl alcohol and phenol; acetaldehyde, propane-2-one (acetone), methanol and acetic acid are oxidized by 50%. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

Energy Technology Data Exchange (ETDEWEB)

Tepper, H.

2005-10-20

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

16. Co-gasification of different rank coals with biomass and petroleum coke in a high-pressure reactor for H(2)-rich gas production.

Science.gov (United States)

Fermoso, J; Arias, B; Gil, M V; Plaza, M G; Pevida, C; Pis, J J; Rubiera, F

2010-05-01

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(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. Copyright 2009 Elsevier Ltd. All rights reserved.

17. Synergistic effect on co-gasification reactivity of biomass-petroleum coke blended char.

Science.gov (United States)

Wei, Juntao; Guo, Qinghua; Gong, Yan; Ding, Lu; Yu, Guangsuo

2017-06-01

In this work, effects of gasification temperature (900°C-1100°C) and blended ratio (3:1, 1:1, 1:3) on reactivity of petroleum coke and biomass co-gasification were studied in TGA. Quantification analysis of active AAEM transformation and in situ investigation of morphological structure variations in gasification were conducted respectively using inductively coupled plasma optical emission spectrometer and heating stage microscope to explore synergistic effect on co-gasification reactivity. The results indicated that char gasification reactivity was enhanced with increasing biomass proportion and gasification temperature. Synergistic effect on co-gasification reactivity was presented after complete generation of biomass ash, and gradually weakened with increasing temperature from 1000°C to 1100°C after reaching the most significant value at 1000°C. This phenomenon was well related with the appearance of molten biomass ash rich in glassy state potassium and the weakest inhibition effect on active potassium transformation during co-gasification at the temperature higher than 1000°C. Copyright © 2017 Elsevier Ltd. All rights reserved.

18. Evaluation of Biomass Gasification to Produce Reburning Fuel for Coal-Fired Boilers

Science.gov (United States)

Gasification and reburning testing with biomass and other wastes is of interest to both the U.S. EPA and the Italian Ministry of the Environment & Territory. Gasification systems that use biofuels or wastes as feedstock can provide a clean, efficient source of synthesis gas and p...

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

Science.gov (United States)

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

2015-02-01

An experimental study of air gasification of rice husk was conducted in a bench-scale fluidized bed gasifier (FBG) having 210 mm diameter and 1600 mm height. Heating of sand bed material was performed using conventional charcoal fuel. Different operating conditions like bed temperature, feeding rate and equivalence ratio (ER) varied in the range of 750-850 °C, 25-31.3 kg/h, and 0.3-0.38, respectively. Flow rate of air was kept constant (37 m(3)/h) during FBG experiments. The carbon conversion efficiencies (CCE), cold gas efficiency, and thermal efficiency were evaluated, where maximum CCE was found as 91%. By increasing ER, the carbon conversion efficiency was decreased. Drastic reduction in electric consumption for initial heating of gasifier bed with charcoal compared to ceramic heater was ∼45%. Hence rice husk is found as a potential candidate to use directly (without any processing) in FBG as an alternative renewable energy source from agricultural field. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

Science.gov (United States)

Allesina, G.; Pedrazzi, S.; Montermini, L.; Giorgini, L.; Bortolani, G.; Tartarini, P.

2014-11-01

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

1. Co-gasification of tire and biomass for enhancement of tire-char reactivity in CO2 gasification process.

Science.gov (United States)

Lahijani, Pooya; Zainal, Zainal Alimuddin; Mohamed, Abdul Rahman; Mohammadi, Maedeh

2013-06-01

In this investigation, palm empty fruit bunch (EFB) and almond shell (AS) were implemented as two natural catalysts rich in alkali metals, especially potassium, to enhance the reactivity of tire-char through co-gasification process. Co-gasification experiments were conducted at several blending ratios using isothermal Thermogravimetric analysis (TGA) under CO2. The pronounced effect of inherent alkali content of biomass-chars on promoting the reactivity of tire-char was proven when acid-treated biomass-chars did not exert any catalytic effect on improving the reactivity of tire-char in co-gasification experiments. In kinetic studies of the co-gasified samples in chemically-controlled regime, modified random pore model (M-RPM) was adopted to describe the reactive behavior of the tire-char/biomass-char blends. By virtue of the catalytic effect of biomass, the activation energy for tire-char gasification was lowered from 250 kJ/mol in pure form 203 to 187 kJ/mol for AS-char and EFB-char co-gasified samples, respectively. Copyright © 2013 Elsevier Ltd. All rights reserved.

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. Small Scale Gasification of Biomass and Municipal Wastes for Heat and Electricity Production using HTAG Technology

Directory of Open Access Journals (Sweden)

Stasiek Jan

2017-01-01

Full Text Available Combustion and gasification technology utilizing high-cycle regenerative air/steam preheater has drawn increased attention in many application areas. The process is to be realized at temperature level above ash melting point using highly preheated agent. The use of highly preheated media above 900°C provides additional energy to conversion processes and results in considerable changes to the design of combustion and gasification equipment and its performance. This paper presents an advanced gasification system that utilizes high-temperature air and steam to convert biomass and municipal wastes into syngas production as well as selected results from experimental studies of high temperature air/steam gasification.

4. Gasification of a Dried Sewage Sludge in a Laboratory Scale Fixed Bed Reactor

Directory of Open Access Journals (Sweden)

Sebastian Werle

2015-08-01

Full Text Available This paper presents an investigation of sewage sludge gasification in a fixed bed gasifier. Experiments were conducted on a laboratory scale fixed bed gasifier. In the experiments, two types of dried sewage sludge were tested and their properties were analysed. Parameters such as air ratio λ = 0.12 to 0.27, gasification agent temperature t = 50 to 250 °C and gasification agent composition ( = 0.21 and  > 0.21 were found to influence on temperature distribution, syngas Lower Heating Value (LHV and syngas composition. The results indicate that the syngas LHV was found to decrease with increased air ratio for all analyzed cases: cold and preheated air and cold enriched air. The increase in the percentage of the main combustible components was accompanied by a decrease in the concentration of carbon dioxide. Increasing oxygen concentration increased the temperature, which tended to favor the formation of smaller molecules in the gas mixture. Thus, the enriched air medium produced a gas with a higher LHV. In contrast to conventional gasification, gasification process with gasification agent preheating causes that the flux of heat necessary to support endothermic gasification reactions is producing more effective. Air preheating causes increases hydrogen and carbon monoxide production.

5. Thermodynamic optimization of biomass gasification for decentralized power generation and Fischer-Tropsch synthesis

Energy Technology Data Exchange (ETDEWEB)

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

2010-06-15

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 C), 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 H{sub 2} and CO in the producer gas, H{sub 2}/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 C, and gasification medium as air. The optimum sets of operating conditions for decentralized power generation are: AR = 0.3-0.4, Temp = 700-800 C 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. (author)

6. Thermodynamic optimization of biomass gasification for decentralized power generation and Fischer-Tropsch synthesis

International Nuclear Information System (INIS)

Buragohain, Buljit; Mahanta, Pinakeswar; Moholkar, Vijayanand S.

2010-01-01

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 o C), 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 H 2 and CO in the producer gas, H 2 /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 o C, and gasification medium as air. The optimum sets of operating conditions for decentralized power generation are: AR = 0.3-0.4, Temp = 700-800 o C 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.

7. Biomass gasification: a strategy for energy recovery and disposal of ...

African Journals Online (AJOL)

Gasification is a process that devoltalizes solid or liquid hydrocarbons, and converts them into a producer gas. There are more than 100 waste gasification facilities operating or under construction around the world. Some plants have been operating commercially for more than five years. Gasification has several advantages ...

8. Biomass Gasification Behavior in an Entrained Flow Reactor: Gas Product Distribution and Soot Formation

DEFF Research Database (Denmark)

Qin, Ke; Jensen, Peter Arendt; Lin, Weigang

2012-01-01

Biomass gasification and pyrolysis were studied in a laboratory-scale atmospheric pressure entrained flow reactor. Effects of operating parameters and biomass types on the syngas composition were investigated. In general, the carbon conversion during biomass gasification was higher than 90......% at the optimal conditions of 1400 °C with steam addition. The biomass carbon that was not converted to gas in the gasification process only appeared as soot particles in the syngas in all of the experiments, except for the two experiments performed at 1000 °C, where a very small amount of char was also left....... In comparison to pyrolysis, lower yields of soot, H2, and CO were produced during gasification. The yield of soot could be reduced by a longer residence time, larger feeder air flow, lower oxygen concentration, higher excess air ratio, higher steam/carbon ratio, and higher reactor temperature. Changes...

9. Policy Impact on Economic Viability of Biomass Gasification Systems in Indonesia

Directory of Open Access Journals (Sweden)

Pranpreya Sriwannawit

2016-03-01

Full Text Available Indonesia is facing challenges on the lack of electricity access in rural areas and the management of agricultural waste. The utilization of waste-to-energy technology can help in mitigating these issues. The aim of this paper is to assess the economic viability of a biomass gasification system for rural electrification by investigating its competitiveness in relation to various government supports. Financial modelling is applied to calculate Net Present Value (NPV, Internal Rate of Return (IRR, and Levelized Cost of Electricity (LCOE. NPV and IRR results indicate that biomass gasification is an economically viable option when appropriate financial government supports exist. LCOE result indicates that biomass gasification system is already more economically competitive compared to diesel generator even without additional support but it is less competitive compared to the national electricity grid tariff. In conclusion, the biomass gasification system is an economically viable option for rural electrification in Indonesian context.

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

Energy Technology Data Exchange (ETDEWEB)

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

1995-12-01

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

11. Treatment of biomass gasification wastewaters using reverse osmosis

Energy Technology Data Exchange (ETDEWEB)

Petty, S.E.; Eliason, S.D.; Laegreid, M.M.

1981-09-01

Reverse osmosis (RO) was evaluated as a treatment technology for the removal of organics from biomass gasification wastewaters (BGW) generated from an experimental biomass gasifier at Texas Tech University. Wastewaters were characteristically high in chemical oxygen demand (COD) with initial values ranging from 32,000 to 68,000 mg/1. Since RO is normally considered a complementary treatment technology, wastewaters were pretreated by biological or wet air oxidation (WAO) processes. One set of experiments were run using untreated wastewaters to compare membrane performance with those experiments using pretreated wastewaters. Experiments were run for 8 to 10 hrs using UOP's TFC-85 membrane operating at 700 psig and 18 to 20/sup 0/C. This membrane is similar to the NS-100, a membrane known for being effective in the separation of organics from solution. Separation of organics from solution was determined by COD removal. Removal percentages for biologically pretreated wastewaters averaged 98% except for one group of runs averaging 69% removal. This exception was probably due to the presence of milk solids in the feed. Use of RO on WAO pretreated wastewaters and unpretreated feeds resulted in 90% COD removal. Membrane degradation was observed when using full-strength and WAO pretreated feeds, but not when using feeds that had undergone biological pretreatment. Color removal was computed for the majority of experiments completed. Overall, 99 to 100% of the total color was removed from BGW feeds, values which coincide with those reported in the literature for other wastewaters.

12. Biomass gasification in near- and super-critical water: Status and prospects

Energy Technology Data Exchange (ETDEWEB)

Matsumura, Yukihiko [Department of Mechanical System Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-hiroshima-shi, Hiroshima 739-8527 (Japan); Minowa, Tomoaki [Biomass Technology Research Laboratory, National Institute of Advanced Industrial Science and Technology, 2-2-2 Hiro-Suehiro, Kure-shi, Hiroshima 737-0197 (Japan); Potic, Biljana; Kersten, Sascha R.A.; Prins, Wolter; van Swaaij, Willibrordus P.M. [TCCB Group, Faculty of Chemical Technology, University of Twente, P.O. Box 217, 7500 AE, Enschede (Netherlands); van de Beld, Bert [Biomass Technology Group B.V., Pantheon 12, 7521 PR, Enschede (Netherlands); Elliott, Douglas C.; Neuenschwander, Gary G. [Pacific Northwest National Laboratory, P.O. Box 999, MSIN K2-12, Richland, Washington 99352 (United States); Kruse, Andrea [Institut fuer Technische Chemie, Forschungszentrum Karlsruhe GmbH, Postfach 3640, D-76021 Karlsruhe (Germany); Jerry Antal Jr., Michael [Hawaii Natural Energy Institute, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, Hawaii 96822 (United States)

2005-10-01

The current status of biomass gasification in near- and supercritical water (SCWG) is reviewed. There are two approaches to biomass gasification in supercritical water. The first: low-temperature catalytic gasification, employs reaction temperature ranging from 350 to 600{sup o}C, and gasifies the feedstock with the aid of metal catalysts. The second: high-temperature supercritical water gasification, employs reaction temperatures ranging from 500 to 750{sup o}C, without catalyst or with non-metallic catalysts. Reviews are made on reaction mechanism, catalyst, and experimental results for these two approaches. Engineering technologies for SCWG gasification, and an example of process analysis are also introduced. Finally, the authors' prognostications on the future prospects of this technology are offered. (author)

13. Biomass gasification with steam and oxygen mixtures at pilot scale and with catalytic gas upgrading. Pt. 1: performance of the gasifier

Energy Technology Data Exchange (ETDEWEB)

Aznar, M.P.; Gil, J.; Martin, M.A.; Caballero, M.A.; Olivares, A.; Perez, P.; Frances, E. [University of Zaragoza (Spain). Dept. of Chemical and Environmental Engineering; Corella, J. [University `Complutense` of Madrid (Spain). Dept. of Chemical Engineering

1997-12-31

Biomass gasification with steam + O{sub 2} mixtures is studied at small pilot plant (10-20 kg/h) scale. The gasifier used is a turbulent fluidised bed of 15 cm. i.d. and 3.3 m high. The pilot plant has a downstream slip flow to study the catalytic upgrading of the raw gas. A guard bed with dolomite and a catalytic bed with a steam reforming catalyst are used and eight different commercial catalysts have been tested to date. Product distribution from the gasifier, including gas proposition and tar content in the gas, are here shown in detail at different (steam + oxygen)/biomass and (H{sub 2}O/O{sub 2}) ratios and gasification temperatures (800-880{sup o}C). (author)

14. Biomass-Ash-Induced Agglomeration in a Fluidized Bed. Part 1: Experimental Study on the Effects of a Gas Atmosphere

DEFF Research Database (Denmark)

Ma, Teng; Fan, Chuigang; Hao, Lifang

2016-01-01

Fluidized beds have been widely applied to gasification and combustion of biomass. During gasification, a high temperature is preferable to increase the carbon conversion and to reduce the undesirable tar. However, the high temperature may lead to a severe agglomeration problem in a fluidized bed....... Understanding of the agglomeration in various atmospheres is crucial to optimize the design and operation conditions. This study focuses on the effects of gases on agglomeration tendency with different types of biomass, including corn straw, rice straw, and wheat straw. The biomass ash samples are mixed...... with quartz sand and fluidized by the gas mixtures of N2/CO2, N2/H2, and N2/steam or by air. At 550 °C, the bed temperature is increased at the rate of 3 °C/min until defluidization occurs. In this way, the defluidization temperature can be determined, which represents the agglomeration tendency...

15. Market Assessment of Biomass Gasification and Combustion Technology for Small- and Medium-Scale Applications

Energy Technology Data Exchange (ETDEWEB)

Peterson, D.; Haase, S.

2009-07-01

This report provides a market assessment of gasification and direct combustion technologies that use wood and agricultural resources to generate heat, power, or combined heat and power (CHP) for small- to medium-scale applications. It contains a brief overview of wood and agricultural resources in the U.S.; a description and discussion of gasification and combustion conversion technologies that utilize solid biomass to generate heat, power, and CHP; an assessment of the commercial status of gasification and combustion technologies; a summary of gasification and combustion system economics; a discussion of the market potential for small- to medium-scale gasification and combustion systems; and an inventory of direct combustion system suppliers and gasification technology companies. The report indicates that while direct combustion and close-coupled gasification boiler systems used to generate heat, power, or CHP are commercially available from a number of manufacturers, two-stage gasification systems are largely in development, with a number of technologies currently in demonstration. The report also cites the need for a searchable, comprehensive database of operating combustion and gasification systems that generate heat, power, or CHP built in the U.S., as well as a national assessment of the market potential for the systems.

16. Solid-gaseous phase transformation of elemental contaminants during the gasification of biomass.

Science.gov (United States)

Jiang, Ying; Ameh, Abiba; Lei, Mei; Duan, Lunbo; Longhurst, Philip

2016-09-01

Disposal of plant biomass removed from heavy metal contaminated land via gasification achieves significant volume reduction and can recover energy. However, these biomass often contain high concentrations of heavy metals leading to hot-corrosion of gasification facilities and toxic gaseous emissions. Therefore, it is of significant interest to gain a further understanding of the solid-gas phase transition of metal(loid)s during gasification. Detailed elemental analyses (C, H, O, N and key metal/metalloid elements) were performed on five plant species collected from a contaminated site. Using multi-phase equilibria modelling software (MTDATA), the analytical data allows modelling of the solid/gas transformation of metal(loid)s during gasification. Thermodynamic modelling based on chemical equilibrium calculations was carried out in this study to predict the fate of metal(loid) elements during typical gasification conditions and to show how these are influenced by metal(loid) composition in the biomass and operational conditions. As, Cd, Zn and Pb tend to transform to their gaseous forms at relatively low temperatures (gasification temperature range of 1000-1200°C. Whereas Cr, Al, Fe and Mg remain in solid phase at higher temperatures (>1200°C). Simulation of pressurised gasification conditions shows that higher pressures increase the temperature at which solid-to-gaseous phase transformations takes place. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

17. Gas, power and heat generation from biomass by allothermal gasification; Gas-, Strom- und Waermeerzeugung aus Biomasse durch allotherme Vergasung

Energy Technology Data Exchange (ETDEWEB)

Yaqub Chughtai, M. [H und C Engineering GmbH, Gummersbach (Germany); Muehlen, H.J. [DMT-Gesellschaft fuer Forschung und Pruefung mbH, Essen (Germany)

1998-09-01

The allothermal DMT gasification process for biomass is a newcomer. The process, its initial materials, the uses of the product gas, and advantages of the allothermal process are described here. (orig./SR) [Deutsch] Der Einsatz des allothermen DMT-Vergasungsverfahrens fuer Biomasse ist neu. Verfahren, Einsatzstoffe und Produktgasnutzung, sowie Vorteile des allothermen Verfahrens werden hier beschrieben. (orig./SR)

18. Oxygen transport membranes for biomass gasification and cement industry

DEFF Research Database (Denmark)

Cheng, Shiyang

Oxygen transport membranes (OTMs) are of particular interest for their potential applications in high purity oxygen separation, biomass gasification and carbon capture and storage in cement production. Gd0.1Ce0.9O1.95-δ (GCO) is one of the interesting materials of OTMs because of its high ionic...... be an interstitial defect in GCO. Also dual phase membranes were studied. A 1-mm thick dual phase composite oxygen membrane (50vol.% Al0.02Ga0.02Zn0.96O1.02-50 vol.% Gd0.1Ce0.9O1.95-δ) with catalyst on both sides was observed to sustain an oxygen flux of 0.3 Nml cm-2 min-1 under air/N2 at 900 °C. The material....... In this study various routes for enhancing the electronic conductivity were investigated; either via elemental substitution or via mixing doped-ceria with another material when forming the membrane layers. The increase of electronic conductivity by substitution co-doped Gd and Pr in ceria was investigated...

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

International Nuclear Information System (INIS)

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

2016-01-01

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

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

International Nuclear Information System (INIS)

Tao, Jun; Lu, Qiang; Dong, Changqing; Du, Xiaoze; Dahlquist, Erik

2015-01-01

Highlights: • ECR technique was proposed to convert biomass gasification tar model compounds. • Electric current enhanced the reforming efficiency remarkably. • The highest toluene conversion reached 99.9%. • Ni–CeO 2 /γ-Al 2 O 3 exhibited good stability during the ECR performance. - Abstract: Electrochemical catalytic reforming (ECR) technique, known as electric current enhanced catalytic reforming technique, was proposed to convert the biomass gasification tar into syngas. In this study, Ni–CeO 2 /γ-Al 2 O 3 catalyst was prepared, and toluene was employed as the major feedstock for ECR experiments using a fixed-bed lab-scale setup where thermal electrons could be generated and provided to the catalyst. Several factors, including the electric current intensity, reaction temperature and steam/carbon (S/C) ratio, were investigated to reveal their effects on the conversion of toluene as well as the composition of the gas products. Moreover, toluene, two other tar model compounds (benzene and 1-methylnaphthalene) and real tar (tar-containing wastewater) were subjected to the long period catalytic stability tests. All the used catalysts were analyzed to determine their carbon contents. The results indicated that the presence of electric current enhanced the catalytic performance remarkably. The toluene conversion reached 99.9% under the electric current of 4 A, catalytic temperature of 800 °C and S/C ratio of 3. Stable conversion performances of benzene, 1-methylnaphthalene and tar-containing wastewater were also observed in the ECR process. H 2 and CO were the major gas products, while CO 2 and CH 4 were the minor ones. Due to the promising capability, the ECR technique deserves further investigation and application for efficient tar conversion

1. Critical factors affecting the integration of biomass gasification and syngas fermentation technology

Directory of Open Access Journals (Sweden)

Karthikeyan D. Ramachandriya

2016-05-01

Full Text Available Gasification-fermentation is a thermochemical-biological platform for the production of fuels and chemicals. Biomass is gasified at high temperatures to make syngas, a gas composed of CO, CO2, H2, N2 and other minor components. Syngas is then fed to anaerobic microorganisms that convert CO, CO2 and H2 to alcohols by fermentation. This platform offers numerous advantages such as flexibility of feedstock and syngas composition and lower operating temperature and pressure compared to other catalytic syngas conversion processes. In comparison to hydrolysis-fermentation, gasification-fermentation has a major advantage of utilizing all organic components of biomass, including lignin, to yield higher fuel production. Furthermore, syngas fermentation microorganisms do not require strict CO:H2:CO2 ratios, hence gas reforming is not required. However, several issues must be addressed for successful deployment of gasification-fermentation, particularly those that involve the integration of gasification and fermentation. Most previous reviews have focused only on either biomass gasification or syngas fermentation. In this review, the critical factors that affect the integration of biomass gasification with syngas fermentation, such as carbon conversion efficiency, effect of trace gaseous species, H2 to CO ratio requirements, and microbial preference of carbon substrate, are thoroughly discussed.

2. Strategy for research, development and demonstration of thermal biomass gasification in Denmark

Energy Technology Data Exchange (ETDEWEB)

Hansen, Morten Tony

2011-12-15

Technology for thermal gasification of biomass is one of the key elements to make the vision of an energy system without fossil fuels a reality. Gasification technology can enhance the flexibility needed to maintain a future energy system with a large share of wind power. Furthermore, gasification has advantages in terms of ash recycling and utilisation of vast but challenging biomass residues. Danish companies are globally well advanced with this technology and the market for gasification technology is great in both Denmark and abroad. There is a clear need for targeted technology RD and D in order to reach the last stretch to a commercial breakthrough. The project ''Strategy for research, development and demonstration of thermal biomass gasification in Denmark'' is the Danish industrys contribution to the development of biomass gasification and goes into detail with the RD and D needs. The project has been conducted by FORCE Technology for DI Bioenergy with funding from EUDP, Energinet.dk, DI Bioenergy and FORCE Technology and five stakeholder companies. (LN)

3. Investigation of Coal-biomass Catalytic Gasification using Experiments, Reaction Kinetics and Computational Fluid Dynamics

Energy Technology Data Exchange (ETDEWEB)

Battaglia, Francine [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Agblevor, Foster [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Klein, Michael [Univ. of Delaware, Newark, DE (United States); Sheikhi, Reza [Northeastern Univ., Boston, MA (United States)

2015-12-31

A collaborative effort involving experiments, kinetic modeling, and computational fluid dynamics (CFD) was used to understand co-gasification of coal-biomass mixtures. The overall goal of the work was to determine the key reactive properties for coal-biomass mixed fuels. Sub-bituminous coal was mixed with biomass feedstocks to determine the fluidization and gasification characteristics of hybrid poplar wood, switchgrass and corn stover. It was found that corn stover and poplar wood were the best feedstocks to use with coal. The novel approach of this project was the use of a red mud catalyst to improve gasification and lower gasification temperatures. An important results was the reduction of agglomeration of the biomass using the catalyst. An outcome of this work was the characterization of the chemical kinetics and reaction mechanisms of the co-gasification fuels, and the development of a set of models that can be integrated into other modeling environments. The multiphase flow code, MFIX, was used to simulate and predict the hydrodynamics and co-gasification, and results were validated with the experiments. The reaction kinetics modeling was used to develop a smaller set of reactions for tractable CFD calculations that represented the experiments. Finally, an efficient tool was developed, MCHARS, and coupled with MFIX to efficiently simulate the complex reaction kinetics.

4. Feasibility study on combining anaerobic digestion and biomass gasification to increase the production of biomethane

International Nuclear Information System (INIS)

Li, Hailong; Larsson, Eva; Thorin, Eva; Dahlquist, Erik; Yu, Xinhai

2015-01-01

Highlights: • Anaerobic digestion and biomass gasification are integrated. • The novel concept can produce much more biomethane. • The novel concept can improve the exergy efficiency. • The novel concept demonstrates a big potential of income increase. - Abstract: There is a rapid growing interest in using biomethane as fuel for transport applications. A new concept is proposed to combine anaerobic digestion and biomass gasification to produce biomethane. H 2 is separated from the syngas generated by biomass gasification in a membrane system, and then is used to upgrade raw biogas from anaerobic digestion. Simulations have been conducted based on the real operation data of one full scale biogas plant and one full scale biomass gasification plant in order to investigate the feasibility of the new concept. Results show that although less power and heat are generated compared to the gasification plant, which results in a lower overall efficiency, much more biomethane can be produced than the biogas plant; and the new concept can achieve a higher exergy efficiency. Due to the increasing price of biomethane, the novel concept demonstrates a big potential of income increase. For example, at a biomethane price of 12.74SEK/kg, the annual income can be increased by 5.3% compared to the total income of the biogas and gasification plant

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

Energy Technology Data Exchange (ETDEWEB)

Holzman, M.I.

1995-08-01

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

6. Supercritical Water Gasification of Biomass : A Literature and Technology Overview

NARCIS (Netherlands)

Yakaboylu, O.; Harinck, J.; Smit, K.G.; De Jong, W.

2014-01-01

The supercritical water gasification process is an alternative to both conventional gasification as well as anaerobic digestion as it does not require drying and the process takes place at much shorter residence times; a few minutes at most. The drastic changes in the thermo-physical properties of

7. Solid–gaseous phase transformation of elemental contaminants during the gasification of biomass

Energy Technology Data Exchange (ETDEWEB)

Jiang, Ying; Ameh, Abiba [Centre for Bioenergy & Resource Management, School of Energy, Environment & Agrifood, Cranfield University, Cranfield MK43 0AL (United Kingdom); Lei, Mei [Centre for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101 (China); Duan, Lunbo [Key Laboratory of Energy Thermal Conversion and Control, Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096 (China); Longhurst, Philip, E-mail: P.J.Longhurst@cranfield.ac.uk [Centre for Bioenergy & Resource Management, School of Energy, Environment & Agrifood, Cranfield University, Cranfield MK43 0AL (United Kingdom)

2016-09-01

Disposal of plant biomass removed from heavy metal contaminated land via gasification achieves significant volume reduction and can recover energy. However, these biomass often contain high concentrations of heavy metals leading to hot-corrosion of gasification facilities and toxic gaseous emissions. Therefore, it is of significant interest to gain a further understanding of the solid–gas phase transition of metal(loid)s during gasification. Detailed elemental analyses (C, H, O, N and key metal/metalloid elements) were performed on five plant species collected from a contaminated site. Using multi-phase equilibria modelling software (MTDATA), the analytical data allows modelling of the solid/gas transformation of metal(loid)s during gasification. Thermodynamic modelling based on chemical equilibrium calculations was carried out in this study to predict the fate of metal(loid) elements during typical gasification conditions and to show how these are influenced by metal(loid) composition in the biomass and operational conditions. As, Cd, Zn and Pb tend to transform to their gaseous forms at relatively low temperatures (< 1000 °C). Ni, Cu, Mn and Co converts to gaseous forms within the typical gasification temperature range of 1000–1200 °C. Whereas Cr, Al, Fe and Mg remain in solid phase at higher temperatures (> 1200 °C). Simulation of pressurised gasification conditions shows that higher pressures increase the temperature at which solid-to-gaseous phase transformations takes place. - Highlights: • Disposal of plants removed from metal contaminated land raises environmental concerns • Plant samples collected from a contaminated site are shown to contain heavy metals. • Gasification is suitable for plant disposal and its emission is modelled by MTDATA. • As, Cd, Zn and Pb are found in gaseous emissions at a low process temperature. • High pressure gasification can reduce heavy metal elements in process emission.

8. Air gasification of rice husk in a dual distributor type fluidized bed gasifier

Energy Technology Data Exchange (ETDEWEB)

Mansaray, K.G.; Ghaly, A.E. [Dalhousie University, Halifax, Nova Scotia (Canada). Biological Engineering Dept.; Al-Taweel, A.M. [Dalhousie University, Halifax, Nova Scotia (Canada). Chemical Engineering Dept.; Hamdullahpur, F.; Ugursal, V.I. [Dalhousie University, Halifax, Nova Scotia (Canada). Mechanical Engineering Dept.

1999-10-01

In this study, a dual distributor type fluidized bed gasifier was used for the air gasification of rice husk in view of producing fuel gas. The effects of varying fluidization velocity (0.22, 0.28 and 0.33 m s{sup -1}) and equivalence ratio (0.25, 0.30 and 0.35) on the gasifier performance were discussed. The steady state temperature varied between 665 and 830 degrees C. The fluidization velocity of 0.22 m s{sup -1} and equivalence ratio of 0.25 appeared to be the optimum conditions with respect to the quality of gas. The mole fractions of the combustible components reached their maximum values at these conditions with a typical gas composition of 4% H{sub 2}, 5% hydrocarbons (CH{sub 4}, C{sub 2}H{sub 2}, C{sub 2}H{sub 4} and C{sub 2}H{sub 6}), 15% CO{sub 2}, 20% CO and 57% N{sub 2}. The higher heating value of the gas obtained at these fluidization velocity and equivalence ratio (3.09 - 5.03 MJ Nm{sup -3}) compared very well with published data from air-blown biomass gasifiers of similar scale of operation. The gas yield and carbon conversion were in the range of 1.30 to 1.98 Nm{sup 3} kg{sup -1} and 55.0 to 81.0%, respectively.

9. Possibilities of CO and H2 Contents Change in the Syngas Produced by Biomass Gasification

Directory of Open Access Journals (Sweden)

Jan JANŠA

2015-06-01

Full Text Available Thermal gasification is an advanced technology to convert purposefully grown or waste ligno-cellulosic biomass into calorific gas. Increasing the content of CO and H2 in the product gas is important for the further use of the gas in technologies for power generation. This article describes the process of gasification and specifies parameters that determine the content of CO and H2 in the produced gas.

10. Biomass-oxygen gasification in a high-temperature entrained-flow gasifier.

Science.gov (United States)

Zhou, Jinsong; Chen, Qing; Zhao, Hui; Cao, Xiaowei; Mei, Qinfeng; Luo, Zhongyang; Cen, Kefa

2009-01-01

The technology associated with indirect biomass liquefaction is currently arousing increased attention, as it could ensure a supply of transportation fuels and reduce the use of petroleum. The characteristics of biomass-oxygen gasification in a bench-scale laminar entrained-flow gasifier were studied in the paper. Experiments were carried out to investigate the influence of some key factors, including reaction temperature, residence time and oxygen/biomass ratio, on the gasification. The results indicated that higher temperature favored H2 and CO production. Cold gas efficiency was improved by N10% when the temperature was increased from 1000 to 1400 degrees C. The carbon conversion increased and the syngas quality was improved with increasing residence time. A shorter residence resulted in incomplete gasification. An optimal residence time of 1.6 s was identified in this study. The introduction of oxygen to the gasifier strengthened the gasification and improved the carbon conversion, but lowered the lower heating value and the H2/CO ratio of the syngas. The optimal oxygen/biomass ratio in this study was 0.4. The results of this study will help to improve our understanding of syngas production by biomass high-temperature gasification.

11. From coal to biomass gasification: Comparison of thermodynamic efficiency

International Nuclear Information System (INIS)

Prins, Mark J.; Ptasinski, Krzysztof J.; Janssen, Frans J.J.G.

2007-01-01

The effect of fuel composition on the thermodynamic efficiency of gasifiers and gasification systems is studied. A chemical equilibrium model is used to describe the gasifier. It is shown that the equilibrium model presents the highest gasification efficiency that can be possibly attained for a given fuel. Gasification of fuels with varying composition of organic matter, in terms of O/C and H/C ratio as illustrated in a Van Krevelen diagram, is compared. It was found that exergy losses in gasifying wood (O/C ratio around 0.6) are larger than those for coal (O/C ratio around 0.2). At a gasification temperature of 927 deg. C, a fuel with O/C ratio below 0.4 is recommended, which corresponds to a lower heating value above 23 MJ/kg. For gasification at 1227 deg. C, a fuel with O/C ratio below 0.3 and lower heating value above 26 MJ/kg is preferred. It could thus be attractive to modify the properties of highly oxygenated biofuels prior to gasification, e.g. by separation of wood into its components and gasification of the lignin component, thermal pre-treatment, and/or mixing with coal in order to enhance the heating value of the gasifier fuel

12. Treatment of Mixed Wastes via Fixed Bed Gasification

Energy Technology Data Exchange (ETDEWEB)

None

1998-10-28

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

13. Taguchi approach for co-gasification optimization of torrefied biomass and coal.

Science.gov (United States)

Chen, Wei-Hsin; Chen, Chih-Jung; Hung, Chen-I

2013-09-01

This study employs the Taguchi method to approach the optimum co-gasification operation of torrefied biomass (eucalyptus) and coal in an entrained flow gasifier. The cold gas efficiency is adopted as the performance index of co-gasification. The influences of six parameters, namely, the biomass blending ratio, oxygen-to-fuel mass ratio (O/F ratio), biomass torrefaction temperature, gasification pressure, steam-to-fuel mass ratio (S/F ratio), and inlet temperature of the carrier gas, on the performance of co-gasification are considered. The analysis of the signal-to-noise ratio suggests that the O/F ratio is the most important factor in determining the performance and the appropriate O/F ratio is 0.7. The performance is also significantly affected by biomass along with torrefaction, where a torrefaction temperature of 300°C is sufficient to upgrade eucalyptus. According to the recommended operating conditions, the values of cold gas efficiency and carbon conversion at the optimum co-gasification are 80.99% and 94.51%, respectively. Copyright © 2013 Elsevier Ltd. All rights reserved.

14. ECONOMIC EVALUATION OF CO2 SEQUESTRATION TECHNOLOGIES TASK 4, BIOMASS GASIFICATION-BASED PROCESSING

Energy Technology Data Exchange (ETDEWEB)

Martha L. Rollins; Les Reardon; David Nichols; Patrick Lee; Millicent Moore; Mike Crim; Robert Luttrell; Evan Hughes

2002-04-01

Biomass derived energy currently accounts for about 3 quads of total primary energy use in the United States. Of this amount, about 0.8 quads are used for power generation. Several biomass energy production technologies exist today which contribute to this energy mix. Biomass combustion technologies have been the dominant source of biomass energy production, both historically and during the past two decades of expansion of modern biomass energy in the U. S. and Europe. As a research and development activity, biomass gasification has usually been the major emphasis as a method of more efficiently utilizing the energy potential of biomass, particularly wood. Numerous biomass gasification technologies exist today in various stages of development. Some are simple systems, while others employ a high degree of integration for maximum energy utilization. The purpose of this study is to conduct a technical and economic comparison of up to three biomass gasification technologies, including the carbon dioxide emissions reduction potential of each. To accomplish this, a literature search was first conducted to determine which technologies were most promising based on a specific set of criteria. During this reporting period, the technical and economic performances of the selected processes were evaluated using computer models and available literature. The results of these evaluations are summarized in this report.

15. ECONOMIC EVALUATION OF CO2 SEQUESTRATION TECHNOLOGIES TASK 4, BIOMASS GASIFICATION-BASED PROCESSING

Energy Technology Data Exchange (ETDEWEB)

Martha L. Rollins; Les Reardon; David Nichols; Patrick Lee; Millicent Moore; Mike Crim; Robert Luttrell; Evan Hughes

2002-06-01

Biomass derived energy currently accounts for about 3 quads of total primary energy use in the United States. Of this amount, about 0.8 quads are used for power generation. Several biomass energy production technologies exist today which contribute to this energy mix. Biomass combustion technologies have been the dominant source of biomass energy production, both historically and during the past two decades of expansion of modern biomass energy in the U. S. and Europe. As a research and development activity, biomass gasification has usually been the major emphasis as a method of more efficiently utilizing the energy potential of biomass, particularly wood. Numerous biomass gasification technologies exist today in various stages of development. Some are simple systems, while others employ a high degree of integration for maximum energy utilization. The purpose of this study is to conduct a technical and economic comparison of up to three biomass gasification technologies, including the carbon dioxide emissions reduction potential of each. To accomplish this, a literature search was first conducted to determine which technologies were most promising based on a specific set of criteria. The technical and economic performances of the selected processes were evaluated using computer models and available literature. Using these results, the carbon sequestration potential of the three technologies was then evaluated. The results of these evaluations are given in this final report.

16. Biomass gasification in district heating systems - The effect of economic energy policies

International Nuclear Information System (INIS)

Wetterlund, Elisabeth; Soederstroem, Mats

2010-01-01

Biomass gasification is considered a key technology in reaching targets for renewable energy and CO 2 emissions reduction. This study evaluates policy instruments affecting the profitability of biomass gasification applications integrated in a Swedish district heating (DH) system for the medium-term future (around year 2025). Two polygeneration applications based on gasification technology are considered in this paper: (1) a biorefinery plant co-producing synthetic natural gas (SNG) and district heat; (2) a combined heat and power (CHP) plant using integrated gasification combined cycle technology. Using an optimisation model we identify the levels of policy support, here assumed to be in the form of tradable certificates, required to make biofuel production competitive to biomass based electricity generation under various energy market conditions. Similarly, the tradable green electricity certificate levels necessary to make gasification based electricity generation competitive to conventional steam cycle technology, are identified. The results show that in order for investment in the SNG biorefinery to be competitive to investment in electricity production in the DH system, biofuel certificates in the range of 24-42 EUR/MWh are needed. Electricity certificates are not a prerequisite for investment in gasification based CHP to be competitive to investment in conventional steam cycle CHP, given sufficiently high electricity prices. While the required biofuel policy support is relatively insensitive to variations in capital cost, the required electricity certificates show high sensitivity to variations in investment costs. It is concluded that the large capital commitment and strong dependency on policy instruments makes it necessary that DH suppliers believe in the long-sightedness of future support policies, in order for investments in large-scale biomass gasification in DH systems to be realised.

17. Power generation based on biomass by combined fermentation and gasification--a new concept derived from experiments and modelling.

Science.gov (United States)

Methling, Torsten; Armbrust, Nina; Haitz, Thilo; Speidel, Michael; Poboss, Norman; Braun-Unkhoff, Marina; Dieter, Heiko; Kempter-Regel, Brigitte; Kraaij, Gerard; Schliessmann, Ursula; Sterr, Yasemin; Wörner, Antje; Hirth, Thomas; Riedel, Uwe; Scheffknecht, Günter

2014-10-01

A new concept is proposed for combined fermentation (two-stage high-load fermenter) and gasification (two-stage fluidised bed gasifier with CO2 separation) of sewage sludge and wood, and the subsequent utilisation of the biogenic gases in a hybrid power plant, consisting of a solid oxide fuel cell and a gas turbine. The development and optimisation of the important processes of the new concept (fermentation, gasification, utilisation) are reported in detail. For the gas production, process parameters were experimentally and numerically investigated to achieve high conversion rates of biomass. For the product gas utilisation, important combustion properties (laminar flame speed, ignition delay time) were analysed numerically to evaluate machinery operation (reliability, emissions). Furthermore, the coupling of the processes was numerically analysed and optimised by means of integration of heat and mass flows. The high, simulated electrical efficiency of 42% including the conversion of raw biomass is promising for future power generation by biomass. Copyright © 2014 Elsevier Ltd. All rights reserved.

18. Solid oxide fuel cells powered by biomass gasification for high efficiency power generation

DEFF Research Database (Denmark)

Gadsbøll, Rasmus Østergaard; Thomsen, Jesper; Bang-Møller, Christian

2017-01-01

efficiencies, flexibility and possibly costs of current biomass power generating systems, a power plant concept combining solid oxide fuel cells (SOFC) and gasification is investigated experimentally. The aim of the study is to examine the commercial operation system potential of these two technologies......Increased use of bioenergy is a very cost-effective and flexible measure to limit changes in the climate and the infrastructure. One of the key technologies toward a higher implementation of biomass is thermal gasification, which enables a wide span of downstream applications. In order to improve...

19. Use of farm waste biomass in the process of gasification for energy production

Energy Technology Data Exchange (ETDEWEB)

Piechocki, J. [Warmia and Mazury Univ., Olsztyn (Poland)

2010-07-01

The process of gasification of waste biomass from farm production was examined along with the energy balance of the process. A newly developed biomass gasification technology that uses manure from poultry farms as the input material was shown to meet all environmental requirements. The gas was purified in a membrane process to increase its calorific value. The gas was then used in an internal combustion engine powering a current generating system to produce electricity and heat in a combined heat and power system (CHP).

20. EVALUATION OF BIOMASS AND COAL CO-GASIFICATION OF BRAZILIAN FEEDSTOCK USING A CHEMICAL EQUILIBRIUM MODEL

Directory of Open Access Journals (Sweden)

R. Rodrigues

Full Text Available Abstract Coal and biomass are energy sources with great potential for use in Brazil. Coal-biomass co-gasification enables the combination of the positive characteristics of each fuel, besides leading to a cleaner use of coal. The present study evaluates the potential of co-gasification of binary coal-biomass blends using sources widely available in Brazil. This analysis employs computational simulations using a reliable thermodynamic equilibrium model. Favorable operational conditions at high temperatures are determined in order to obtain gaseous products suitable for energy cogeneration and chemical synthesis. This study shows that blends with biomass ratios of 5% and equivalence ratios ≤ 0.3 lead to high cold gas efficiencies. Suitable gaseous products for chemical synthesis were identified at biomass ratios ≤ 35% and moisture contents ≥ 40%. Formation of undesirable nitrogen and sulfur compounds was also analyzed.

1. Thermodynamic approach to biomass gasification; Approche thermodynamique des transformations de la biomasse

Energy Technology Data Exchange (ETDEWEB)

Boissonnet, G.; Seiler, J.M.

2003-07-01

The document presents an approach of biomass transformation in presence of steam, hydrogen or oxygen. Calculation results based on thermodynamic equilibrium are discussed. The objective of gasification techniques is to increase the gas content in CO and H{sub 2}. The maximum content in these gases is obtained when thermodynamic equilibrium is approached. Any optimisation action of a process. will, thus, tend to approach thermodynamic equilibrium conditions. On the other hand, such calculations can be used to determine the conditions which lead to an increase in the production of CO and H{sub 2}. An objective is also to determine transformation enthalpies that are an important input for process calculations. Various existing processes are assessed, and associated thermodynamic limitations are evidenced. (author)

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

Energy Technology Data Exchange (ETDEWEB)

Kurkela, E.; Hepola, J. [VTT Energy, Espoo (Finland); Haukka, P.; Raiko, R. [Helsinki Univ. of Technology, Otaniemi (Finland). Lab. of Thermal Engineering

1995-11-01

This project is an extension of the earlier Liekki-project 402, which was carried out in 1993-1994 in the Department of Thermal Engineering of Tampere University of Technology (TUT). In the previous project the feasibility of a two-stage entrained-flow gasification was studied by the means of process modeling and pyrolysis experiments. The present project carried out in cooperation with the Gasification Research Group of VTT and TUT. The aims of the project are: (a) to study the formation of blematic tar/soot compounds and nitrogen compounds in the conditions entrained flow gasification of biomass and peat, (b) to study the product yields and kinetics of pyrolysis and (c) to develop simulation methods for entrained flow pyrolysis and gasification. (author)

3. Impact of feedstock properties and operating conditions on sewage sludge gasification in a fixed bed gasifier.

Science.gov (United States)

Werle, Sebastian

2014-10-01

This work presents results of experimental studies on the gasification process of granulated sewage sludge in a laboratory fixed bed gasifier. Nowadays, there is a large and pressing need for the development of thermal methods for sewage sludge disposal. Gasification is an example of thermal method that has several advantages over the traditional combustion. Gasification leads to a combustible gas, which can be used for the generation of useful forms of final energy. It can also be used in processes, such as the drying of sewage sludge directly in waste treatment plant. In the present work, the operating parameters were varied over a wide range. Parameters, such as air ratio λ = 0.12 to 0.27 and the temperature of air preheating t = 50 °C to 250 °C, were found to influence temperature distribution and syngas properties. The results indicate that the syngas heating value decreases with rising air ratio for all analysed cases: i.e. for both cold and preheated air. The increase in the concentration of the main combustible components was accompanied by a decrease in the concentration of carbon dioxide. Preheating of the gasification agent supports the endothermic gasification and increases hydrogen and carbon monoxide production. © The Author(s) 2014.

4. Influence of pyrolysis conditions on the structure and gasification reactivity of biomass chars

Energy Technology Data Exchange (ETDEWEB)

E. Cetin; B. Moghtaderi; R. Gupta; T.F. Wall [University of Newcastle, Callaghan, NSW (Australia). Discipline of Chemical Engineering, Faculty of Engineering and Built Environment, School of Engineering

2004-11-01

The physical and chemical structure as well as gasification reactivities of chars generated from several biomass species (i.e. pinus radiata, eucalyptus maculata and sugar cane bagasse) were studied to gain insight into the role of heating rate and pressure on the gasification characteristics of biomass chars. Char samples were generated in a suite of reactors including a wire mesh reactor, a tubular reactor, and a drop tube furnace. Scanning electron microscopy analysis, X-ray diffractometry, digital cinematography and surface area analysis were employed to determine the impact of operating conditions on the char structure. The global gasification reactivities of char samples were also determined for a range of pressures between 1 and 20 bar using pressurised thermogravimetric analysis technique. Char reactivities were found to increase with increasing pyrolysis heating rates and decreasing pyrolysis pressure. It was found that under high heating rates the char particles underwent plastic deformation (i.e. melted) developing a structure different to that of the virgin biomass. Pressure was also found to influence the physical and chemical structures of char particles. The difference in the gasification reactivities of biomass chars at pressure was found to correlate well with the effect of pyrolysis pressure on the graphitisation process in the biomass char structure. 29 refs., 18 figs., 2 tabs.

5. Analysis of energetic and exergetic efficiency, and environmental benefits of biomass integrated gasification combined cycle technology.

Science.gov (United States)

Mínguez, María; Jiménez, Angel; Rodríguez, Javier; González, Celina; López, Ignacio; Nieto, Rafael

2013-04-01

The problem of the high carbon dioxide emissions linked to power generation makes necessary active research on the use of biofuels in gas turbine systems as a promising alternative to fossil fuels. Gasification of biomass waste is particularly of interest in obtaining a fuel to be run in gas turbines, as it is an efficient biomass-to-biofuel conversion process, and an integration into a combined cycle power plant leads to a high performance with regard to energetic efficiency. The goal of this study was to carry out an energetic, exergetic and environmental analysis of the behaviour of an integrated gasification combined cycle (IGCC) plant fuelled with different kinds of biomass waste by means of simulations. A preliminary economic study is also included. Although a technological development in gasification technology is necessary, the results of simulations indicate a high technical and environmental interest in the use of biomass integrated gasification combined cycle (BioIGCC) systems for large-scale power generation from biomass waste.

6. Characterization of Residual Particulates from Biomass Entrained Flow Gasification

DEFF Research Database (Denmark)

Qin, Ke; Lin, Weigang; Fæster, Søren

2013-01-01

below 100 nm to above 100 nm. During gasification of dried lignin, the filter sample mainly consists of soot and nonvolatilizable inorganic matter. SEM images of the parent wood particles and the derived char samples show that they have similar structure, size, and shape but the derived char particle...... surface looks smoother indicating some degree of melting. The reactivity of the organic fraction of the samples was determined by thermogravimetry, and it was found that char was more reactive than soot with respect to both oxidation and CO2 gasification. The activation energy for the soot conversion...

7. Performance of HT-WGS Catalysts for Upgrading of Syngas Obtained from Biomass Gasification

Energy Technology Data Exchange (ETDEWEB)

Marano Bujan, M.; Sanchez Hervas, J. M.

2009-05-21

Oxygen pressurized gasification of biomass out stands as a very promising approach to obtain energy or hydrogen from renewable sources. The technical feasibility of this technology is being investigated under the scope of the VI FP CHRISGAS project, which has started in September 2004 and has a duration of five years. The Division of Combustion and Gasification of CIEMAT participates in this project in Work Package 13: Ancillary and novel processes, studying innovative gas separation and gas upgrading systems. Such systems include novel or available high temperature water gas shift catalysts and commercially available membranes not yet tried in this type of atmosphere. This report describes the activities carried out during the period 2005-2007 regarding the performance of high temperature water gas shift catalysts for upgrading of synthesis gas obtained from biomass gasification. (Author) 28 refs.

8. Power production from biomass III. Gasification and pyrolysis R and D and D for industry

Energy Technology Data Exchange (ETDEWEB)

Sipilae, K.; Korhonen, M. [eds.] [VTT Energy, Espoo (Finland). New Energy Technologies

1999-07-01

The Seminar on Power Production from Biomass III. Gasification and Pyrolysis R and D and D for Industry, was held on 14-15 September 1998 in Espoo. The seminar was organised by VTT Energy in co-operation with the University of Groningen, EU-Thermie Programme and Technology Development Centre, Finland (Tekes). Overviews of current activities on power production from biomass and wastes in Europe and in the United States were given, and all European and U. S. demonstration projects on biomass gasification were presented. In Europe, the target is to produce additional 90 Mtoe/a of bioenergy for the market by 2010. This is a huge challenge for the bioenergy sector, including biomass production and harvesting, conversion technology, energy companies, and end users. In USA, U.S. Department of Energy is promoting the Biomass Power Programme to encourage and assist industry in the development and validation of renewable, biomass-based electricity generation systems, the objective being to double the present use of 7 000 MW biomass power by the year 2010. The new Finnish PROGAS Programme initiated by VTT was also introduced. Several gasification projects are today on the demonstration stage prior to entering the commercial level. Pyrolysis technologies are not yet on the demonstration stage on the energy market. Bio-oils can easily be transported, stored and utilised in existing boiler and diesel plants. The proceedings include the presentations given by the keynote speakers and other invited speakers, as well as some extended poster presentations. (orig.)

9. 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)

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

OpenAIRE

Zhang, Qinglin

2011-01-01

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

11. 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.

12. Structural evolution of biomass char and its effect on the gasification rate

DEFF Research Database (Denmark)

Fatehi, Hesameddin; Bai, Xue Song

2017-01-01

during the entire conversion process. This model is used to analyze the steam gasification process of biomass char of centimeter sizes. The results from the present multi-pore model are in better agreement with experimental data than those from a corresponding single pore model. Since the multi......-pore model accommodates the detailed intra-particle transport, it is a useful basis toward developing a more predictive model for biomass char gasification....... with different radii. The model is valid for biomass chars produced under relatively low heating rates, when the original beehive structure of the biomass is not destroyed during the pyrolysis stage. The contribution of different pores with different radius is taken into account using an effectiveness factor...

13. Metal catalysts for steam reforming of tar derived from the gasification of lignocellulosic biomass.

Science.gov (United States)

Li, Dalin; Tamura, Masazumi; Nakagawa, Yoshinao; Tomishige, Keiichi

2015-02-01

Biomass gasification is one of the most important technologies for the conversion of biomass to electricity, fuels, and chemicals. The main obstacle preventing the commercial application of this technology is the presence of tar in the product gas. Catalytic reforming of tar appears a promising approach to remove tar and supported metal catalysts are among the most effective catalysts. Nevertheless, improvement of catalytic performances including activity, stability, resistance to coke deposition and aggregation of metal particles, as well as catalyst regenerability is greatly needed. This review focuses on the design and catalysis of supported metal catalysts for the removal of tar in the gasification of biomass. The recent development of metal catalysts including Rh, Ni, Co, and their alloys for steam reforming of biomass tar and tar model compounds is introduced. The role of metal species, support materials, promoters, and their interfaces is described. Copyright © 2014 Elsevier Ltd. All rights reserved.

14. ZERO-DIMENSIONAL MODEL OF A DIMETHYL ETHER (DME) PLANT BASED ON GASIFICATION OF TORREFIED BIOMASS

DEFF Research Database (Denmark)

Clausen, Lasse Røngaard; Elmegaard, Brian; Houbak, Niels

2009-01-01

A model of a DME fuel production plant was designed and analyzed in Aspen Plus. The plant produces DME by catalytic conversion of a syngas generated by gasification of torrefied woody biomass. Torrefication is a mild pyrolysis process that takes place at 200-300°C. Torrefied biomass has propertie...... % (LHV) from torrefied biomass to DME and 70 % (LHV) if the exported electricity is included. When accounting for raw, untreated biomass, the efficiency for DME production is reduced to about 60 %....... similar to coal, which enables the use of commercially available coal gasification processing equipment. The DME plant model is integrated with a steam cycle that utilizes waste heat from the plant and covers the on-site electricity consumption. The plant model predicts a fuel production efficiency of 67...

15. Application of a Cloud Model-Set Pair Analysis in Hazard Assessment for Biomass Gasification Stations.

Science.gov (United States)

Yan, Fang; Xu, Kaili

2017-01-01

Because a biomass gasification station includes various hazard factors, hazard assessment is needed and significant. In this article, the cloud model (CM) is employed to improve set pair analysis (SPA), and a novel hazard assessment method for a biomass gasification station is proposed based on the cloud model-set pair analysis (CM-SPA). In this method, cloud weight is proposed to be the weight of index. In contrast to the index weight of other methods, cloud weight is shown by cloud descriptors; hence, the randomness and fuzziness of cloud weight will make it effective to reflect the linguistic variables of experts. Then, the cloud connection degree (CCD) is proposed to replace the connection degree (CD); the calculation algorithm of CCD is also worked out. By utilizing the CCD, the hazard assessment results are shown by some normal clouds, and the normal clouds are reflected by cloud descriptors; meanwhile, the hazard grade is confirmed by analyzing the cloud descriptors. After that, two biomass gasification stations undergo hazard assessment via CM-SPA and AHP based SPA, respectively. The comparison of assessment results illustrates that the CM-SPA is suitable and effective for the hazard assessment of a biomass gasification station and that CM-SPA will make the assessment results more reasonable and scientific.

16. Fuzzy Bayesian Network-Bow-Tie Analysis of Gas Leakage during Biomass Gasification.

Directory of Open Access Journals (Sweden)

Fang Yan

Full Text Available Biomass gasification technology has been rapidly developed recently. But fire and poisoning accidents caused by gas leakage restrict the development and promotion of biomass gasification. Therefore, probabilistic safety assessment (PSA is necessary for biomass gasification system. Subsequently, Bayesian network-bow-tie (BN-bow-tie analysis was proposed by mapping bow-tie analysis into Bayesian network (BN. Causes of gas leakage and the accidents triggered by gas leakage can be obtained by bow-tie analysis, and BN was used to confirm the critical nodes of accidents by introducing corresponding three importance measures. Meanwhile, certain occurrence probability of failure was needed in PSA. In view of the insufficient failure data of biomass gasification, the occurrence probability of failure which cannot be obtained from standard reliability data sources was confirmed by fuzzy methods based on expert judgment. An improved approach considered expert weighting to aggregate fuzzy numbers included triangular and trapezoidal numbers was proposed, and the occurrence probability of failure was obtained. Finally, safety measures were indicated based on the obtained critical nodes. The theoretical occurrence probabilities in one year of gas leakage and the accidents caused by it were reduced to 1/10.3 of the original values by these safety measures.

17. Fuzzy Bayesian Network-Bow-Tie Analysis of Gas Leakage during Biomass Gasification.

Science.gov (United States)

Yan, Fang; Xu, Kaili; Yao, Xiwen; Li, Yang

2016-01-01

Biomass gasification technology has been rapidly developed recently. But fire and poisoning accidents caused by gas leakage restrict the development and promotion of biomass gasification. Therefore, probabilistic safety assessment (PSA) is necessary for biomass gasification system. Subsequently, Bayesian network-bow-tie (BN-bow-tie) analysis was proposed by mapping bow-tie analysis into Bayesian network (BN). Causes of gas leakage and the accidents triggered by gas leakage can be obtained by bow-tie analysis, and BN was used to confirm the critical nodes of accidents by introducing corresponding three importance measures. Meanwhile, certain occurrence probability of failure was needed in PSA. In view of the insufficient failure data of biomass gasification, the occurrence probability of failure which cannot be obtained from standard reliability data sources was confirmed by fuzzy methods based on expert judgment. An improved approach considered expert weighting to aggregate fuzzy numbers included triangular and trapezoidal numbers was proposed, and the occurrence probability of failure was obtained. Finally, safety measures were indicated based on the obtained critical nodes. The theoretical occurrence probabilities in one year of gas leakage and the accidents caused by it were reduced to 1/10.3 of the original values by these safety measures.

18. Electric power generation from biomass gasification; Geracao de eletricidade a partir da gaseificacao de biomassa

Energy Technology Data Exchange (ETDEWEB)

Sales, Cristina Aparecida Vilas Boas de; Andrade, Rubenildo Vieira; Lora, Electo Eduardo Silva [Universidade Federal de Itajuba (NEST/IEM/UNIFEI), MG (Brazil). Inst. de Engenharia Mecanica. Nucleo de Estudos em Sistemas Termicos], e-mails: cristinasales@unifei.edu.br, ruben@unifei.edu.br, electo@unifei.edu.br

2006-07-01

This paper presents a techno-economical evaluation of the biomass gasification utilization with different technologies such as: reciprocating engine, gas micro turbine, Stirling engine and fuel cells for small scale electricity generation. The comparative evaluation about the technologies is limited to the utilization in isolated areas. This paper shows the principal characteristics of these technologies. (author)

19. Production of high quality syngas from argon/water plasma gasification of biomass and waste

Czech Academy of Sciences Publication Activity Database

Hlína, Michal; Hrabovský, Milan; Kavka, Tetyana; Konrád, Miloš

2014-01-01

Roč. 34, č. 1 (2014), s. 63-66 ISSN 0956-053X R&D Projects: GA ČR GAP205/11/2070; GA MŠk MEB020814 Institutional support: RVO:61389021 Keywords : Biomass * Gasification * Plasma * Tar Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 3.220, year: 2014

20. Single char particle model for naphthalene reduction in a biomass gasification system

NARCIS (Netherlands)

Abu El-Rub, Ziad; Brem, Gerrit; Bramer, Eduard A.

2015-01-01

Tar removal in biomass gasification systems is one of the key challenges to overcome for the successful commercialization of this technology. This study focused on tar conversion over the active char particle besides the simultaneous carbon conversion of the char particle. In the presented model,

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

Energy Technology Data Exchange (ETDEWEB)

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

1996-12-31

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

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

Energy Technology Data Exchange (ETDEWEB)

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

1983-09-01

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

3. Power generation from biomass: Status report on catalytic-allothermal wood gasification. Papers; Energetische Nutzung von Biomasse: Stand der Realisierung der katalytisch-allothermen Holzvergasung. Vortraege

Energy Technology Data Exchange (ETDEWEB)

Spindler, H.; Bauermeister, U.; Kliche, H.; Seiffarth, K. (comps.)

2001-12-01

The topic of this event is bound up with the activities of FOeST in the field of gasification of biomass in decentralized small plants (< 2 MW{sub el}). The start project was a research work in 1993 to select a gasification process for using wood, sludge or plastic waste, continued 1995 by a research project with gasification tests of tar oil contaminated wood in a small gasification reactor with good results in environmental compatibility. But the following planning process of a demonstration plant for 500 kW{sub el} has shown, that the biomass gasification couldn't reach economic efficiency. Due to the development of an catalytic-partial allothermal gasification process of GNS ltd. it was clear, that the technical efficiency could be increased considerably. So, in 2000, a project started to test this catalytic-partial allothermal gasification in a pilot plant. Today the results of research, development and testing of biomass gasification with catalytic-partial allothermal processing as well as practically experience with a gasification plant, general conditions and further activities for energetically utilisation of biomass in Saxonia-Anhalt will be presented. (orig.)

4. Experimental study of cyclone pyrolysis - Suspended combustion air gasification of biomass.

Science.gov (United States)

Zhao, Yijun; Feng, Dongdong; Zhang, Zhibo; Sun, Shaozeng; Zhou, Xinwei; Luan, Jiyi; Wu, Jiangquan

2017-11-01

Based on the original biomass cyclone gasifier, the cyclone pyrolysis-suspension combustion gasification technology was constituted with a bottom wind ring to build the biochar suspension combustion zone. This technology decouples the biomass pyrolysis, gasification (reduction reaction) and combustion (oxidation reaction) within the same device. With the feed amount and total air fixed, the effect of air rate arrangement on temperature distribution of the gasifier, syngas components and gasification parameters was studied. With the secondary air rate (0.20) and bottom air rate (0.50), the gasification efficiency was best, with gas heating value of 5.15MJ/Nm 3 , carbon conversion rate of 71.50%, gasification efficiency of 50.80% and syngas yield of 1.29Nm 3 /kg. The device with biochar for the tar catalytic cracking was installed at the gasifier outlet, effectively reducing the tar content in syngas, with a minimum value of 1.02g/Nm 3 . Copyright © 2017 Elsevier Ltd. All rights reserved.

5. Interaction and kinetic analysis for coal and biomass co-gasification by TG-FTIR.

Science.gov (United States)

Xu, Chaofen; Hu, Song; Xiang, Jun; Zhang, Liqi; Sun, Lushi; Shuai, Chao; Chen, Qindong; He, Limo; Edreis, Elbager M A

2014-02-01

This study aims to investigate the interaction and kinetic behavior of CO2 gasification of coal, biomass and their blends by thermogravimetry analysis (TG). The gas products evolved from gasification were measured online with Fourier Transform Infrared Spectroscopy (FTIR) coupled with TG. Firstly, TG experiments indicated that interaction between the coals and biomasses mainly occurred during co-gasification process. The most significant synergistic interaction occurred for LN with SD at the blending mass ratio 4:1. Furthermore, thermal kinetic analysis indicated that the activation energy involved in co-gasification decreased as the SD content increased until the blending ratio of SD with coal reached 4:1. The rise of the frequency factor indicated that the increase of SD content favored their synergistic interaction. Finally, FTIR analysis of co-gasification of SD with LN indicated that except for CO, most gases including CH3COOH, C6H5OH, H2O, etc., were detected at around 50-700°C. Copyright © 2014. Published by Elsevier Ltd.

6. Tar removal during the fluidized bed gasification of plastic waste.

Science.gov (United States)

Arena, Umberto; Zaccariello, Lucio; Mastellone, Maria Laura

2009-02-01

A recycled polyethylene was fed in a pilot plant bubbling fluidized bed gasifier, having an internal diameter of 0.381 m and a maximum feeding capacity of 90 kg/h. The experimental runs were carried out under various operating conditions: the bed temperature was kept at about 850 degrees C, the equivalence ratio varied between 0.2 and 0.35, the amount of bed material was between 131 and 215 kg, the fluidizing velocity was between 0.5 and 0.7 m/s, quartz sand and olivine were used as bed material, and air and steam were used as fluidizing reactants. The results confirm that the tar removal treatments applied inside the gasifier (primary methods) can eliminate or strongly reduce the need for a further downstream cleanup of the syngas. In particular, the utilization of a natural olivine as an in situ tar reduction agent remarkably improves the quality of the product gas, in terms of both high hydrogen volumetric fraction and larger syngas yield.

7. Thermodynamic Analyses of Biomass Gasification Integrated Externally Fired, Post-Firing and Dual-Fuel Combined Cycles

Directory of Open Access Journals (Sweden)

Saeed Soltani

2015-01-01

Full Text Available In the present work, the results are reported of the energy and exergy analyses of three biomass-related processes for electricity generation: the biomass gasification integrated externally fired combined cycle, the biomass gasification integrated dual-fuel combined cycle, and the biomass gasification integrated post-firing combined cycle. The energy efficiency for the biomass gasification integrated post-firing combined cycle is 3% to 6% points higher than for the other cycles. Although the efficiency of the externally fired biomass combined cycle is the lowest, it has an advantage in that it only uses biomass. The energy and exergy efficiencies are maximized for the three configurations at particular values of compressor pressure ratios, and increase with gas turbine inlet temperature. As pressure ratio increases, the mass of air per mass of steam decreases for the biomass gasification integrated post-firing combined cycle, but the pressure ratio has little influence on the ratio of mass of air per mass of steam for the other cycles. The gas turbine exergy efficiency is the highest for the three configurations. The combustion chamber for the dual-fuel cycle exhibits the highest exergy efficiency and that for the post-firing cycle the lowest. Another benefit of the biomass gasification integrated externally fired combined cycle is that it exhibits the highest air preheater and heat recovery steam generator exergy efficiencies.

8. Oxygen transfer materials with catalytic properties for biomass gasification[Dissertation 17302

Energy Technology Data Exchange (ETDEWEB)

Pecho, J.

2007-06-15

By application of olivine as bed material in a biomass gasifier such as the FICFB type (Fast Internal Circulating Fluidized Bed) in Guessing, Austria, an improvement of the gasification process was observed. Reduction of tars was measured and oxygen increase in the process was calculated. However, it took a while before these properties became clear. Aim of the project was to elucidate the mechanism with which olivine influences the system and to find a new material with improved properties for the gasification process. There were some factors which had be taken into account, e.g., amount of free lattice oxygen, reaction enthalpy, selectivity, mechanical and chemical stability, costs, desulphurization and decarbonisation. Several studies have shown that natural olivine ((Fe{sub x}Mg{sub 1-x}){sub 2}SiO{sub 4}) lowers tar formation in fluidized bed gasification of biomass. According to most authors, the phenomenon is related to the presence of iron oxide (Fe{sub 2}O{sub 3}) which is, e.g., formed during the calcination of olivine in air. To elucidate the role of the iron oxide, synthetic olivine with a molar ratio of Fe:Mg equal to unity has been exposed to gases that contained either wet methane or wet toluene as the only carbon source in a thermobalance interfaced to on-line gas analysis. The results provide strong evidence that the conversion of the carbon species is dominated by the stoichiometric reaction of binary iron oxide with hydrocarbons in the beginning of the reaction while catalytic reactions such as steam reforming contribute little to the observed tar reduction. This reaction path straightforwardly explains the influence of the olivine's origin or the pre-treatment on its chemical reactivity as it was reported by the various authors. To improve the catalytic properties and oxygen capacity of bed materials, we put our focus on perovskite type oxides La{sub x}Sr{sub 1-x}Cr{sub y}Mn{sub 1-y}O{sub 3} and Ba{sub 0.3}Sr{sub 0.7}Fe{sub 0.9}Mn{sub 0.1}O

9. Biomass Gasification. The characteristics of technology development and the rate of learning

Energy Technology Data Exchange (ETDEWEB)

Dorca Duch, Andreu; Huertas Bermejo, Javier

2008-09-15

Gasification is considered one of the most promising technologies in biomass applications. The higher efficiency compared to boiler power systems, the perspectives in fuel synthesis and its environmental friendly features are some examples of its potential. Biomass gasification has evolved since its first applications, but it has not been possible to reach a solid commercial stage, except during periods of crises and only for some specific applications. Meanwhile, other gasification technologies, fed by fossil fuels, are currently widely used on industrial scales. This thesis aims to analyze the knowledge development and diffusion patterns of the biomass gasification technology since 1970s in Austria, Finland, Germany and Sweden. Additionally, it seeks to identify the factors that strengthen and weaken the learning process. Finally, the concept of learning curve will be used to numerically assess the rate of learning in small scale biomass gasification for electricity generation. The feasibility of various future scenarios will be evaluated in order to know what is the likelihood for the technology to become competitive in the short term. To do so, the historical evolution of biomass gasification in Austria, Finland, Germany and Sweden has been analyzed. These countries have been selected due to the increasing number of ongoing projects and initiatives since 1970. Subsequently, the development of this technology has been encouraged by two historical facts. Initially, the price of fossil fuels grew in 1973 and 1979 enhancing the interest for biomass gasification as a future alternative. Afterwards, the willingness, shown by the mentioned countries, to reduce greenhouse gases emissions following the Kyoto protocol has revived the interest in biomass gasification. However, none of these two events has driven this technology sufficiently to achieve a sustainable commercial status. In addition, small and large scale projects have followed different development processes

10. Low temperature circulating fluidized bed gasification and co-gasification of municipal sewage sludge. Part 1: Process performance and gas product characterization

DEFF Research Database (Denmark)

Thomsen, Tobias Pape; Sárossy, Zsuzsa; Gøbel, Benny

2017-01-01

Results from five experimental campaigns with Low Temperature Circulating Fluidized Bed (LT-CFB) gasification of straw and/or municipal sewage sludge (MSS) from three different Danish municipal waste water treatment plants in pilot and demonstration scale are analyzed and compared. The gasification...... process is characterized with respect to process stability, process performance and gas product characteristics. All experimental campaigns were conducted at maximum temperatures below 750°C, with air equivalence ratios around 0.12 and with pure silica sand as start-up bed material. A total of 8600kg...... particles in the system. Co-gasification of MSS with sufficient amounts of cereal straw was found to be an effective way to mitigate these issues as well as eliminate thermal MSS drying requirements. Characterization of gas products and process performance showed that even though gas composition varied...

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

International Nuclear Information System (INIS)

Nsamba Hussein Kisiki; Amran Mohammad Salleh; Wan Azlina; Hamdan Yusof

2010-01-01

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

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

Science.gov (United States)

Dalai, Ajay K; Batta, Nishant; Eswaramoorthi, I; Schoenau, Greg J

2009-01-01

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

13. 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

14. 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

15. High temperature air-blown woody biomass gasification model for the estimation of an entrained down-flow gasifier.

Science.gov (United States)

Kobayashi, Nobusuke; Tanaka, Miku; Piao, Guilin; Kobayashi, Jun; Hatano, Shigenobu; Itaya, Yoshinori; Mori, Shigekatsu

2009-01-01

A high temperature air-blown gasification model for woody biomass is developed based on an air-blown gasification experiment. A high temperature air-blown gasification experiment on woody biomass in an entrained down-flow gasifier is carried out, and then the simple gasification model is developed based on the experimental results. In the experiment, air-blown gasification is conducted to demonstrate the behavior of this process. Pulverized wood is used as the gasification fuel, which is injected directly into the entrained down-flow gasifier by the pulverized wood banner. The pulverized wood is sieved through 60 mesh and supplied at rates of 19 and 27kg/h. The oxygen-carbon molar ratio (O/C) is employed as the operational condition instead of the air ratio. The maximum temperature achievable is over 1400K when the O/C is from 1.26 to 1.84. The results show that the gas composition is followed by the CO-shift reaction equilibrium. Therefore, the air-blown gasification model is developed based on the CO-shift reaction equilibrium. The simple gasification model agrees well with the experimental results. From calculations in large-scale units, the cold gas is able to achieve 80% efficiency in the air-blown gasification, when the woody biomass feedrate is over 1000kg/h and input air temperature is 700K.

16. Effect of Heating Method on Hydrogen Production by Biomass Gasification in Supercritical Water

Directory of Open Access Journals (Sweden)

Qiuhui Yan

2014-01-01

Full Text Available The glucose as a test sample of biomass is gasified in supercritical water with different heating methods driven by renewable solar energy. The performance comparisons of hydrogen production of glucose gasification are investigated. The relations between temperature raising speed of reactant fluid, variation of volume fraction, combustion enthalpy, and chemical exergy of H2 of the product gases with reactant solution concentration are presented, respectively. The results show that the energy quality of product gases with preheating process is higher than that with no preheating unit for hydrogen production. Hydrogen production quantity and gasification rate of glucose decrease obviously with the increase of concentration of material in no preheating system.

17. Study on CO₂ gasification properties and kinetics of biomass chars and anthracite char.

Science.gov (United States)

Wang, Guangwei; Zhang, Jianliang; Hou, Xinmei; Shao, Jiugang; Geng, Weiwei

2015-02-01

The CO2 gasification properties and kinetics of three biomass chars (WS-char, RL-char and PS-char) and anthracite char (AC-char) were investigated by thermogravimetric analysis method. Three nth-order representative gas-solid reaction models, random pore model (RPM), volume reaction model (VM) and unreacted core model (URCM) were employed to describe the reactive behavior of chars. Results show that gasification reactivity order of different chars from high to low was WS-char, PS-char, RL-char and AC-char. In addition, the chemical components as well as physical structures of four chars were systematically tested. It was found that gasification properties of char were determined by carbonaceous structure. It was concluded from kinetics analysis that RPM model was the best model for describing the reactivities of biomass chars and VM was the model that best fitted the gasification process of anthracite char. The activation energies obtained for the biomass and anthracite char samples lie in the range of 236.4-284.9 kJ/mol. Copyright © 2014 Elsevier Ltd. All rights reserved.

18. Methods for sulfate removal in liquid-phase catalytic hydrothermal gasification of biomass

Science.gov (United States)

Elliott, Douglas C; Oyler, James

2013-12-17

Processing of wet biomass feedstock by liquid-phase catalytic hydrothermal gasification must address catalyst fouling and poisoning. One solution can involve heating the wet biomass with a heating unit to a pre-treatment temperature sufficient for organic constituents in the feedstock to decompose, for precipitates of inorganic wastes to form, for preheating the wet feedstock in preparation for subsequent removal of soluble sulfate contaminants, or combinations thereof. Processing further includes reacting the soluble sulfate contaminants with cations present in the feedstock material to yield a sulfate-containing precipitate and separating the inorganic precipitates and/or the sulfate-containing precipitates out of the wet feedstock. Having removed much of the inorganic wastes and the sulfate contaminants that can cause poisoning and fouling, the wet biomass feedstock can be exposed to the heterogenous catalyst for gasification.

19. Supercritical Water Gasification of Biomass in a Ceramic Reactor: Long-Time Batch Experiments

DEFF Research Database (Denmark)

Castello, Daniele; Rolli, Birgit; Kruse, Andrea

2017-01-01

Supercritical water gasification (SCWG) is an emerging technology for the valorization of (wet) biomass into a valuable fuel gas composed of hydrogen and/or methane. The harsh temperature and pressure conditions involved in SCWG (T > 375 ◦C, p > 22 MPa) are definitely a challenge for the manufact......Supercritical water gasification (SCWG) is an emerging technology for the valorization of (wet) biomass into a valuable fuel gas composed of hydrogen and/or methane. The harsh temperature and pressure conditions involved in SCWG (T > 375 ◦C, p > 22 MPa) are definitely a challenge...... effect of the material can influence the gas yield and composition. In this work, a research reactor featuring an internal alumina inlay was utilized to conduct long-time (16 h) batch tests with real biomasses and model compounds. The same experiments were also conducted in batch reactors made...

20. Effect of biomass containing zinc metal at different operating parameters on gasification efficiency.

Science.gov (United States)

Lin, Chiou-Liang; Chen, Hsien

2015-01-01

This paper describes the effect of Zn on the gas production of a fluidized-bed gasifier to determine the relationship between Zn and the gasification process. Different concentrations of Zn were used in the preparation of artificial waste to elucidate the effect on gas product composition, gas product heat value, gas production rate, and H2 yield in the gasification process. Zn served to increase H2 generation during the gasification process. The molar percentage of H2 with more than 0.1 wt% additional Zn increased by 33.02% and the H2 yield was increased by 11.34% compared to that without Zn. However, the gas heat value decreased, and no significant change in the gas production rate was noted.

1. Effects of Biomass Feedstocks and Gasification Conditions on the Physiochemical Properties of Char

Directory of Open Access Journals (Sweden)

Raymond L. Huhnke

2013-08-01

Full Text Available Char is a low-value byproduct of biomass gasification and pyrolysis with many potential applications, such as soil amendment and the synthesis of activated carbon and carbon-based catalysts. Considering these high-value applications, char could provide economic benefits to a biorefinery utilizing gasification or pyrolysis technologies. However, the properties of char depend heavily on biomass feedstock, gasifier design and operating conditions. This paper reports the effects of biomass type (switchgrass, sorghum straw and red cedar and equivalence ratio (0.20, 0.25 and 0.28, i.e., the ratio of air supply relative to the air that is required for stoichiometric combustion of biomass, on the physiochemical properties of char derived from gasification. Results show that the Brunauer-Emmett-Teller (BET surface areas of most of the char were 1–10 m2/g and increased as the equivalence ratio increased. Char moisture and fixed carbon contents decreased while ash content increased as equivalence ratio increased. The corresponding Fourier Transform Infrared spectra showed that the surface functional groups of char differed between biomass types but remained similar with change in equivalence ratio.

2. Artificial neural network based modelling approach for municipal solid waste gasification in a fluidized bed reactor.

Science.gov (United States)

Pandey, Daya Shankar; Das, Saptarshi; Pan, Indranil; Leahy, James J; Kwapinski, Witold

2016-12-01

In this paper, multi-layer feed forward neural networks are used to predict the lower heating value of gas (LHV), lower heating value of gasification products including tars and entrained char (LHV p ) and syngas yield during gasification of municipal solid waste (MSW) during gasification in a fluidized bed reactor. These artificial neural networks (ANNs) with different architectures are trained using the Levenberg-Marquardt (LM) back-propagation algorithm and a cross validation is also performed to ensure that the results generalise to other unseen datasets. A rigorous study is carried out on optimally choosing the number of hidden layers, number of neurons in the hidden layer and activation function in a network using multiple Monte Carlo runs. Nine input and three output parameters are used to train and test various neural network architectures in both multiple output and single output prediction paradigms using the available experimental datasets. The model selection procedure is carried out to ascertain the best network architecture in terms of predictive accuracy. The simulation results show that the ANN based methodology is a viable alternative which can be used to predict the performance of a fluidized bed gasifier. Copyright © 2016 Elsevier Ltd. All rights reserved.

3. Chemical hot gas purification for biomass gasification processes; Chemische Heissgasreinigung bei Biomassevergasungsprozessen

Energy Technology Data Exchange (ETDEWEB)

Stemmler, Michael

2010-07-01

The German government decided to increase the percentage of renewable energy up to 20 % of all energy consumed in 2020. The development of biomass gasification technology is advanced compared to most of the other technologies for producing renewable energy. So the overall efficiency of biomass gasification processes (IGCC) already increased to values above 50 %. Therefore, the production of renewable energy attaches great importance to the thermochemical biomass conversion. The feedstock for biomass gasification covers biomasses such as wood, straw and further energy plants. The detrimental trace elements released during gasification of these biomasses, e.g. KCl, H{sub 2}S and HCl, cause corrosion and harm downstream devices. Therefore, gas cleaning poses an especial challenge. In order to improve the overall efficiency this thesis aims at the development of gas cleaning concepts for the allothermic, water blown gasification at 800 C and 1 bar (Guessing-Process) as well as for the autothermic, water and oxygen blown gasification at 950 C and 18 bar (Vaernamo-Process). Although several mechanisms for KCl- and H{sub 2}S-sorption are already well known, the achievable reduction of the contamination concentration is still unknown. Therefore, calculations on the produced syngas and the chemical hot gas cleaning were done with a thermodynamic process model using SimuSage. The syngas production was included in the calculations because the knowledge of the biomass syngas composition is very limited. The results of these calculations prove the dependence of syngas composition on H{sub 2}/C-ratio and ROC (Relative Oxygen Content). Following the achievable sorption limits were detected via experiments. The KCl containing syngases were analysed by molecular beam mass spectrometry (MBMS). Furthermore, an optimised H{sub 2}S-sorbent was developed because the examined sorbents exceeded the sorption limit of 1 ppmv. The calculated sorption limits were compared to the limits

4. Commercial steam reforming catalysts to improve biomass gasification with steam-oxygen mixtures. 1: Hot gas upgrading by the catalytic reactor

Energy Technology Data Exchange (ETDEWEB)

Caballero, M.A.; Aznar, M.P.; Gil, J.; Martin, J.A.; Frances, E. [Univ. of Saragossa (Spain). Chemical and Environmental Engineering Dept.; Corella, J. [Univ. of Complutense of Madrid (Spain). Chemical Engineering Dept.

1997-12-01

Commercial steam reforming (nickel-based) catalysts are used for hot gas cleaning and upgrading in biomass gasification with steam-oxygen mixtures. The gasifier used was an atmospheric and bubbling fluidized bed with an internal diameter of 15 cm and a total height of 3.2 m and was continuously fed with 5--20 kg of biomass/h. Eight different catalysts from four different manufacturers (BASF AG, TOPSOE A/S, ICI, and UCI) have been tested. They were located in a downflow fixed-bed reactor of 4 cm i.d. placed in a slip flow after the gasifier. A guard bed with a calcined dolomite was also used before the catalytic bed to decrease the tar content in the raw gas below the limit of 2 g of tar/m{sup 3}{sub n}, thus avoiding the catalyst deactivation by coke formation. The main variables studied were the temperature of the catalytic bed and the gas composition in the bed. Effects concerning tar elimination will be reported in part 2 of this work. This paper is mainly devoted to characterization of catalysts and to upgrading of the flue gas. H{sub 2} and CO contents increased by 4--14 and 1--8 vol%, dry basis, respectively. CO{sub 2}, CH{sub 4}, and steam contents decreased by 0--14, 87--99, and 2--6 vol %, dry basis, respectively. Other parameters varied in the following ways: the lower heating value decreased by 0.3--1.7 MJ/m{sup 3}{sub n}, gas yield increased by 0.1--0.4 m{sup 3}{sub n}/kg of biomass daf, and apparent thermal efficiency increased by 1--20%. The results presented allow screening of the best catalysts to get an upgraded and useful gas in biomass gasification with steam-oxygen mixtures.

5. Hydrogen production from biomass. Optimization of gasification by experimental by experimental statistical design; Produccion de hidrogeno a partir de biomasa. Optimizacion de la gasificacion por aplicacion del diseno estadistico de experimentos

Energy Technology Data Exchange (ETDEWEB)

Arteche Calvo, A.

2008-07-01

Biomass conversion into a gas with high content in hydrogen is considered as a future alternative to obtain energy and chemicals products for renewable sources. One of the current technologies for this purpose is the gasification using steam as gasification agent. The technical objective of this work is the study of the process of biomass gasification with steam and oxygen as thermochemical process of transformation of biomass to obtain the maximum amount of hydrogen with lowest tar content. Materials and Methods. An experimental statistical strategy with three variables and two levels of operation was planned to optimize the gasification process. the study was conducted without changing the type of biomass-fed, the type of catalyst used and the quantity of bed inside the gasifier. Two mathematical models have been obtained as results. Both of them correlated the experimental factors to the production of hydrogen and tars. The design of experiments methodology has been applied to assess the influence os several experimental factors, such as the introduced amount of steam, the use of catalyst and oxygen, both in the production of hydrogen, as in the minimization of the formation of tars. This statistical technique has enabled the modeling of the selected biomass gasification performing the minimum number of pilot plant tests to identify possible improvements and optimizations both in the yield of produced hydrogen as in the generation of tars. (Author) 10 refs.

6. Process simulation of ethanol production from biomass gasification and syngas fermentation.

Science.gov (United States)

Pardo-Planas, Oscar; Atiyeh, Hasan K; Phillips, John R; Aichele, Clint P; Mohammad, Sayeed

2017-12-01

The hybrid gasification-syngas fermentation platform can produce more bioethanol utilizing all biomass components compared to the biochemical conversion technology. Syngas fermentation operates at mild temperatures and pressures and avoids using expensive pretreatment processes and enzymes. This study presents a new process simulation model developed with Aspen Plus® of a biorefinery based on a hybrid conversion technology for the production of anhydrous ethanol using 1200tons per day (wb) of switchgrass. The simulation model consists of three modules: gasification, fermentation, and product recovery. The results revealed a potential production of about 36.5million gallons of anhydrous ethanol per year. Sensitivity analyses were also performed to investigate the effects of gasification and fermentation parameters that are keys for the development of an efficient process in terms of energy conservation and ethanol production. Copyright © 2017 Elsevier Ltd. All rights reserved.

7. Adiabatic Fixed-Bed Gasification of Colombian Coffee Husk Using Air-Steam Blends for Partial Oxidation

Directory of Open Access Journals (Sweden)

Javier Bonilla

2017-01-01

Full Text Available The increasing energy consumption, mostly supplied by fossil fuels, has motivated the research and development of alternative fuel technologies to decrease the humanity’s dependence on fossil fuels, which leads to pollution of natural sources. Small-scale biomass gasification, using air-steam blends for partial oxidation, is a good alternative since biomass is a neutral carbon feedstock for sustainable energy generation. This research presents results obtained from an experimental study on coffee husk (CH gasification, using air-steam blends for partial oxidation in a 10 kW fixed-bed gasifier. Parametric studies on equivalence ratio (ER (1.53 < ER < 6.11 and steam-fuel (SF ratio (0.23 < SF < 0.89 were carried out. The results show that increasing both SF and ER results in a syngas rich in CH4 and H2 but poor in CO. Also, decreased SF and ER decrease the peak temperature (Tpeak at the gasifier combustion zone. The syngas high heating value (HHV ranged from 3112 kJ/SATPm3 to 5085 kJ/SATPm3 and its maximum value was obtained at SF = 0.87 and ER = 4.09. The dry basis molar concentrations of the species, produced under those operating conditions (1.53 < ER < 6.11 and 0.23 < SF < 0.89, were between 1.12 and 4.1% for CH4, between 7.77 and 13.49% for CO, and between 7.54 and 19.07% for H2. Other species were in trace amount.

8. Low temperature circulating fluidized bed gasification and co-gasification of municipal sewage sludge. Part 2: Evaluation of ash materials as phosphorus fertilizer.

Science.gov (United States)

Thomsen, Tobias Pape; Hauggaard-Nielsen, Henrik; Gøbel, Benny; Stoholm, Peder; Ahrenfeldt, Jesper; Henriksen, Ulrik B; Müller-Stöver, Dorette Sophie

2017-08-01

The study is part 2 of 2 in an investigation of gasification and co-gasification of municipal sewage sludge in low temperature gasifiers. In this work, solid residuals from thermal gasification and co-gasification of municipal sewage sludge were investigated for their potential use as fertilizer. Ashes from five different low temperature circulating fluidized bed (LT-CFB) gasification campaigns including two mono-sludge campaigns, two sludge/straw mixed fuels campaigns and a straw reference campaign were compared. Experiments were conducted on two different LT-CFBs with thermal capacities of 100kW and 6MW, respectively. The assessment included: (i) Elemental composition and recovery of key elements and heavy metals; (ii) content of total carbon (C) and total nitrogen (N); (iii) pH; (iv) water extractability of phosphorus after incubation in soil; and (v) plant phosphorus response measured in a pot experiment with the most promising ash material. Co-gasification of straw and sludge in LT-CFB gasifiers produced ashes with a high content of recalcitrant C, phosphorus (P) and potassium (K), a low content of heavy metals (especially cadmium) and an improved plant P availability compared to the mono-sludge ashes, thereby showing the best fertilizer qualities among all assessed materials. It was also found that bottom ashes from the char reactor contained even less heavy metals than cyclone ashes. It is concluded that LT-CFB gasification and co-gasification is a highly effective way to purify and sanitize sewage sludge for subsequent use in agricultural systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

9. Design and Optimization of an Integrated Biomass Gasification and Solid Oxide Fuel Cell System

DEFF Research Database (Denmark)

Bang-Møller, Christian

based on biomass will improve the competitiveness of decentralized CHP production from biomass as well as move the development towards a more sustainable CHP production. The aim of this research is to contribute to enhanced electrical efficiencies and sustainability in future decentralized CHP plants......-level modelling study of three conceptual plant designs based on two-stage gasification of wood chips with a thermal biomass input of ~0.5 MWth (LHV) is presented. Product gas is converted in a micro gas turbine (MGT) in the first plant design, in SOFCs in the second, and in a combined SOFC-MGT arrangement......Development of sustainable power plants has gained focus in the recent years and utilization of biomass resources are seen as a pathway towards a sustainable combined heat and power (CHP) production. Biomass resources are distributed, thus decentralized biomass conversion would avoid extensive cost...

10. Syngas suitability for solid oxide fuel cells applications produced via biomass steam gasification process: Experimental and modeling analysis

Science.gov (United States)

Pieratti, Elisa; Baratieri, Marco; Ceschini, Sergio; Tognana, Lorenzo; Baggio, Paolo

The technologies and the processes for the use of biomass as an energy source are not always environmental friendly. It is worth to develop approaches aimed at a more sustainable exploitation of biomass, avoiding whenever possible direct combustion and rather pursuing fuel upgrade paths, also considering direct conversion to electricity through fuel cells. In this context, it is of particular interest the development of the biomass gasification technology for synthesis gas (i.e., syngas) production, and the utilization of the obtained gas in fuel cells systems, in order to generate energy from renewable resources. Among the different kind of fuel cells, SOFCs (solid oxide fuel cells), which can be fed with different type of fuels, seem to be also suitable for this type of gaseous fuel. In this work, the syngas composition produced by means of a continuous biomass steam gasifier (fixed bed) has been characterized. The hydrogen concentration in the syngas is around 60%. The system is equipped with a catalytic filter for syngas purification and some preliminary tests coupling the system with a SOFCs stack are shown. The data on the syngas composition and temperature profile measured during the experimental activity have been used to calibrate a 2-dimensional thermodynamic equilibrium model.

11. Experimental and Simulation Studies on Biomass Torrefaction and Gasification

OpenAIRE

Tapasvi, Dhruv

2015-01-01

The potential for bioenergy in Norway is significant. This potential can be realized by improving the properties of biomass and making it a convenient and competitive alternative to other fuels. Torrefaction is the most promising biomass pretreatment technique to date, improving its effectiveness as a fuel in various thermochemical processes. Torrefaction considerably reduces moisture content but increases the heating value, hydrophobicity and grindability of biomass. Torrefact...

12. Practical achievements on biomass steam gasification in a rotary tubular coiled-downdraft reactor.

Science.gov (United States)

Andrew, Renny; Gokak, D T; Sharma, Pankaj; Gupta, Shalini

2016-12-01

Today, the impending stringent environmental norms and concerns about the depletion of fossil fuel reserves have added impetus on development of cutting edge technologies for production of alternative fuels from renewable sources, like biomass. The concept of biomass pyro-gasification offers a platform for production of (a) hydrogen, (b) hydrocarbons and (c) value added chemicals, etc. In this context, there exists potential for hydrogen production from biomass by superheated steam gasification. Apart from H 2 , gaseous products of biomass steam gasification contain CO, CH 4 and other hydrocarbons that can be converted to hydrogen through cracking, steam reforming and water gas shift reactions. In the present work, the characteristics of biomass steam gasification in an indigenously designed rotary tubular coiled-downdraft reactor for high value gaseous fuel production from rice husk was studied through a series of experiments. The robust reactor system enhances biomass conversion to gaseous products by improved mass and heat transfer within the system induced by a coiled flow pattern with increased heat transfer area. Also, the system has improved upon the reliability of operation and offered greater continuity of the process and easier control in comparison with a conventional process by making use of an innovative gas cooler assembly and efficient venturi-mixing system for biomass and steam. Subsequently, the effects of reactor temperature, steam-to-biomass ratio and residence time on overall product gas yield and hydrogen yield were investigated. From the experimental results, it can be deduced that an optimum reactor temperature of 750 °C, steam-to-biomass ratio of 2.0 and a residence time of 3.0 min contributed highest gas yield (1.252 Nm 3  kg -1 moisture-free biomass). Based on the obtained experimental results, a projected potential hydrogen yield of 8.6 wt% of the moisture-free biomass could be achieved, and is also practical for production of

13. A Life Cycle Assessment on a Fuel Production Through Distributed Biomass Gasification Process

Science.gov (United States)

Dowaki, Kiyoshi; Eguchi, Tsutomu; Ohkubo, Rui; Genchi, Yutaka

In this paper, we estimated life cycle inventories (energy intensities and CO2 emissions) on the biomass gasification CGS, Bio-H2, Bio-MeOH (methanol) and Bio-DME (di-methyl ether), using the bottom-up methodology. CO2 emissions and energy intensities on material's chipping, transportation and dryer operation were estimated. Also, the uncertainties on the moisture content of biomass materials and the transportation distance to the plant were considered by the Monte Carlo simulation. The energy conversion system was built up by gasification through the BLUE Tower process, with either CGS, PSA (Pressure Swing Absorption) system or the liquefaction process. In our estimation, the biomass materials were the waste products from Japanese Cedar. The uncertainties of moisture content and transportation distance were assumed to be 20 to 50 wt.% and 5 to 50 km, respectively. The capability of the biomass gasification plant was 10 t-dry/d, that is, an annual throughput of 3,000 t-dry/yr. The production energy in each case was used as a functional unit. Finally, the energy intensities of 1.12 to 3.09 MJ/MJ and CO2 emissions of 4.79 to 88.0 g-CO2/MJ were obtained. CGS case contributes to the environmental mitigation, and Bio-H2 and/or Bio-DME cases have a potential to reduce CO2 emissions, compared to the conventional ones.

14. Process simulation of single-step dimethyl ether production via biomass gasification.

Science.gov (United States)

Ju, Fudong; Chen, Hanping; Ding, Xuejun; Yang, Haiping; Wang, Xianhua; Zhang, Shihong; Dai, Zhenghua

2009-01-01

In this study, we simulated the single-step process of dimethyl ether (DME) synthesis via biomass gasification using ASPEN Plus. The whole process comprised four parts: gasification, water gas shift reaction, gas purification, and single-step DME synthesis. We analyzed the influence of the oxygen/biomass and steam/biomass ratios on biomass gasification and synthesis performance. The syngas H(2)/CO ratio after water gas shift process was modulated to 1, and the syngas was then purified to remove H(2)S and CO(2), using the Rectisol process. Syngas still contained trace amounts of H(2)S and about 3% CO(2) after purification, which satisfied the synthesis demands. However, the high level of cold energy consumption was a problem during the purification process. The DME yield in this study was 0.37, assuming that the DME selectivity was 0.91 and that CO was totally converted. We performed environmental and economic analyses, and propose the development of a poly-generation process based on economic considerations.

15. Thermodynamic analysis of hydrogen production from biomass gasification in supercritical water

International Nuclear Information System (INIS)

Yan Qiuhui; Guo Liejin; Lu Youjun

2006-01-01

A non-stoichiometric thermodynamic model based on minimum free energy is developed to predict the performance of hydrogen production from biomass gasification in SCW (supercritical water). Specially, we take glucose as a test sample of biomass and apply this model to analyze the processes of hydrogen production from glucose gasification in SCW. It is found that there is a 'fast water-gas-shift-type pathway ', and the product gases consist primarily of hydrogen and carbon dioxide with small amounts of methane and carbon monoxide. When the reaction temperature reaches a higher value, the equilibrium gases consist only of hydrogen and carbon dioxide. The gas yields, higher heating value, gasification efficiency and cold gasification efficiency are strongly affected by the reaction temperature and feedstock concentration and less affected by the pressure under the following range of conditions: a temperature of 650-1050 K, a pressure of 20-35 MPa and a concentration of 0.1-1.0 M. The higher the molar ratio of C/O, the higher are the maximum theoretical yields of hydrogen. The trend of the prediction results is in good agreement with the experimental data, especially as we take into consideration the carbon conversion efficiency

16. 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.

17. Supercritical Water Gasification of Wet Biomass : Modeling and Experiments

NARCIS (Netherlands)

Yakaboylu, O.

2016-01-01

In the following decades, biomass will play an important role among the other renewable energy sources globally as it is already the fourth largest energy resource after coal, oil and natural gas. It is possible to obtain gaseous, liquid or solid biofuels from biomass via thermochemical or

18. A new model for coal gasification on pressurized bubbling fluidized bed gasifiers

International Nuclear Information System (INIS)

Sánchez, Cristian; Arenas, Erika; Chejne, Farid; Londoño, Carlos A.; Cisneros, Sebastian; Quintana, Juan C.

2016-01-01

Highlights: • A new model was proposed for the simulation of fluidized bed reactors. • The model was validated against experimental data found in the literature. • The model was compared and found to be superior to other models reported in the literature. • Effects of pressure, temperature, steam/coal and air/coal ratios over gas composition were studied. - Abstract: Many industries have taken interest in the use of coal gasification for the production of chemicals and fuels. This gasification can be carried out inside a fluidized bed reactor. This non-ideal reactor is difficult to predict due to the complex physical phenomena and the different chemical changes that the feedstock undergoes. The lack of a good model to simulate the reactor’s behavior produces less efficient processes and plant designs. Various approaches to the proper simulation of such reactor have been proposed. In this paper, a new model is developed for the simulation of a pressurized bubbling fluidized bed (PBFB) gasifier that rigorously models the physical phenomena and the chemical changes of the feedstock inside the reactor. In the model, the reactor is divided into three sections; devolatilization, volatile reactions and combustion-gasification. The simulation is validated against experimental data reported in the literature and compared with other models proposed by different authors; once the model is validated, the dependence of the syngas composition on operational pressure, temperature, steam/coal and air/coal ratios are studied. The results of this article show how this model satisfactorily predicts the performance of PBFB gasifiers.

19. Interaction and its induced inhibiting or synergistic effects during co-gasification of coal char and biomass char.

Science.gov (United States)

Ding, Liang; Zhang, Yongqi; Wang, Zhiqing; Huang, Jiejie; Fang, Yitian

2014-12-01

Co-gasification of coal char and biomass char was conducted to investigate the interactions between them. And random pore model (RPM) and modified random pore model (MRPM) were applied to describe the gasification behaviors of the samples. The results show that inhibiting effect was observed during co-gasification of corn stalk char with Hulunbeier lignite coal char, while synergistic effects were observed during co-gasification of corn stalk char with Shenmu bituminous coal char and Jincheng anthracite coal char. The inhibiting effect was attributed to the intimate contact and comparable gasification rate between biomass char and coal char, and the loss of the active form of potassium caused by the formation of KAlSiO4, which was proved to be inactive during gasification. While the synergistic effect was caused by the high potassium content of biomass char and the significant difference of reaction rate between coal char and biomass char during gasification. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

Science.gov (United States)

Yan, Linbo; Yue, Guangxi; He, Boshu

2016-04-01

A novel chemical looping power generation system is presented based on the biomass-coal co-gasification with steam. The effects of different key operation parameters including biomass mass fraction (Rb), steam to carbon mole ratio (Rsc), gasification temperature (Tg) and iron to fuel mole ratio (Rif) on the system performances like energy efficiency (ηe), total energy efficiency (ηte), exergy efficiency (ηex), total exergy efficiency (ηtex) and carbon capture rate (ηcc) are analyzed. A benchmark condition is set, under which ηte, ηtex and ηcc are found to be 39.9%, 37.6% and 96.0%, respectively. Furthermore, detailed energy Sankey diagram and exergy Grassmann diagram are drawn for the entire system operating under the benchmark condition. The energy and exergy efficiencies of the units composing the system are also predicted. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

International Nuclear Information System (INIS)

Jarungthammachote, S.; Dutta, A.

2008-01-01

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

2. Anaerobic digestion and gasification hybrid system for potential energy recovery from yard waste and woody biomass

International Nuclear Information System (INIS)

Yao, Zhiyi; Li, Wangliang; Kan, Xiang; Dai, Yanjun; Tong, Yen Wah; Wang, Chi-Hwa

2017-01-01

There is a rapid growing interest in using biomass as an alternative source for clean and sustainable energy production. In this work, a hybrid system was developed to combine anaerobic digestion (AD) and gasification for energy recovery from yard waste and woody biomass. The feasibility of the proposed hybrid system was validated experimentally and numerically and the energy efficiency was maximized by varying energy input in the drying process. The experiments were performed in two stages. At the first stage, AD of yard waste was conducted by mixing with anaerobic sludge. At the second stage, co-gasification was added as post-treatment for the AD residue for syngas production. The co-gasification experiments of AD residue and woody biomass were conducted at varying mixing ratios and varying moisture contents of AD residue. Optimal energy efficiency was found to be 70.8% at mixing ratio of 20 wt% AD residue with 30 wt% moisture content. Two kinetic models were then adapted for prediction of biogas produced in AD process and syngas produced in gasification process, respectively. Both experimental and numerical results showed that full utilization of biomass could be realized to produce energy through the combination of these two technologies. - Highlights: • The feasibility of the proposed two-stage hybrid system was validated experimentally and numerically. • The proposed hybrid system could effectively improve the quality of produced gas. • The operating parameters were optimized to improve the overall energy efficiency of the system. • Drying process was found to play an important role in determining overall energy efficiency. • Optimal moisture content of AD residue was investigated for maximizing energy efficiency.

3. Combined hydrothermal liquefaction and catalytic hydrothermal gasification system and process for conversion of biomass feedstocks

Energy Technology Data Exchange (ETDEWEB)

Elliott, Douglas C.; Neuenschwander, Gary G.; Hart, Todd R.

2017-09-12

A combined hydrothermal liquefaction (HTL) and catalytic hydrothermal gasification (CHG) system and process are described that convert various biomass-containing sources into separable bio-oils and aqueous effluents that contain residual organics. Bio-oils may be converted to useful bio-based fuels and other chemical feedstocks. Residual organics in HTL aqueous effluents may be gasified and converted into medium-BTU product gases and directly used for process heating or to provide energy.

4. Combined heat and power production through biomass gasification with 'Heatpipe-Reformer'

International Nuclear Information System (INIS)

Iliev, I.; Kamburova, V.; Terziev, A.

2013-01-01

The current report aims is to analyze the system for combined heat and power production through biomass gasification with “heatpipe-reformer” system. Special attention is paid on the process of synthetic gas production in the Reformer, its cleaning and further burning in the co-generation unit. A financial analysis is made regarding the investments and profits generated by the combined heat and power production. (authors)

5. Investigating Efficient Tar Management from Biomass and Waste to Energy Gasification Processes

Science.gov (United States)

2015-04-01

tars or allow them to react excessively. A collet creates a minimal air leak path while the ball valve is opened and the probe is slid into...Heated Gravimetric Tar Sampling Probe. Figure 20 shows the actual heated probe along with the airlock system of the 2” ball valve and collet...FINAL REPORT Investigating Efficient Tar Management from Biomass and Waste to Energy Gasification Processes SERDP Project WP-2236 APRIL

6. Char and coke formation as unwanted side reaction of the hydrothermal biomass gasification

Energy Technology Data Exchange (ETDEWEB)

Karayildirim, T. [Department of Chemistry, Science Faculty, Ege University, Bornova-Izmir (Turkey); Sinag, A. [Department of Chemistry, Science Faculty, Ankara University, Besevler-Ankara (Turkey); Kruse, A. [Institut fuer Technische Chemie CPV, Forschungszentrum Karlsruhe GmbH, Karlsruhe (Germany)

2008-11-15

The hydrothermal biomass gasification is a promising technology to produce hydrogen and/or methane from wet biomass with a water content of {>=}80 % (g/g). In the process, the coke formation usually is very low, but already low amounts may cause problems like, e.g., fouling in the heat exchanger. To learn more about the product formation, the results of the hydrothermal treatment (at 400,500,600 C and 1 h) of different biomass feedstocks (artichoke stalk, pinecone, sawdust, and cellulose as model biomass) in a microreactor are compared. The gas composition and the total organic carbon content of the aqueous phase were determined after reaction. The gas formation rises with increasing temperature. The formation of carbon deposits and their characterization has been investigated by scanning electron microscopy (SEM). The variation of the solid morphology during the hydrothermal conversion is discussed based on chemical pathways occurring during hydrothermal biomass degradation. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

7. An ecological and economic assessment of absorption-enhanced-reforming (AER) biomass gasification

International Nuclear Information System (INIS)

Heffels, Tobias; McKenna, Russell; Fichtner, Wolf

2014-01-01

Highlights: • Analysis of biomass gasification with new absorption enhanced reforming technology. • Energy- and mass balances for three different process configurations to produce heat, SNG and/or hydrogen. • Ecological (based on LCA) and economic (based on production costs) assessment of the technology. • Comparison of results with existing operational plants producing similar products. - Abstract: Biomass gasification with absorption enhanced reforming (AER) is a promising technology to produce a hydrogen-rich product gas that can be used to generate electricity, heat, substitute natural gas (SNG) and hydrogen (5.0 quality). To evaluate the production of the four products from an ecological and economic point of view, three different process configurations are considered. The plant setup involves two coupled fluidized beds: the steam gasifier and the regenerator. Subsequently the product gas can be used to operate a CHP plant (configuration one), be methanised (configuration two) or used to produce high-quality hydrogen (configuration three). Regarding ecological criteria, the global warming potential, the acidification potential and the cumulative energy demand of the processes are calculated, based on a life-cycle assessment approach. The economic analysis is based on the levelized costs of energy generation (LCOE). The AER-based processes are compared to conventional and renewable reference processes, which they might stand to substitute. The results show that the AER processes are beneficial from an ecological point of view as they are less carbon intensive (mitigating up to 800gCO 2 -eq.kW -1 h el -1 ), require less fossil energy input (only about 0.5kWh fossil kW -1 h el -1 ) and have a comparable acidification potential (300–900mgSO 2 -eq.kW -1 h el -1 ) to most reference processes. But the results depend heavily on the extent to which excess heat can be used to replace conventional heating processes, and hence on the exact location of the plant

8. A novel hazard assessment method for biomass gasification stations based on extended set pair analysis.

Science.gov (United States)

Yan, Fang; Xu, Kaili; Li, Deshun; Cui, Zhikai

2017-01-01

Biomass gasification stations are facing many hazard factors, therefore, it is necessary to make hazard assessment for them. In this study, a novel hazard assessment method called extended set pair analysis (ESPA) is proposed based on set pair analysis (SPA). However, the calculation of the connection degree (CD) requires the classification of hazard grades and their corresponding thresholds using SPA for the hazard assessment. In regard to the hazard assessment using ESPA, a novel calculation algorithm of the CD is worked out when hazard grades and their corresponding thresholds are unknown. Then the CD can be converted into Euclidean distance (ED) by a simple and concise calculation, and the hazard of each sample will be ranked based on the value of ED. In this paper, six biomass gasification stations are introduced to make hazard assessment using ESPA and general set pair analysis (GSPA), respectively. By the comparison of hazard assessment results obtained from ESPA and GSPA, the availability and validity of ESPA can be proved in the hazard assessment for biomass gasification stations. Meanwhile, the reasonability of ESPA is also justified by the sensitivity analysis of hazard assessment results obtained by ESPA and GSPA.

9. Biomass gasification chars for mercury capture from a simulated flue gas of coal combustion.

Science.gov (United States)

Fuente-Cuesta, A; Diaz-Somoano, M; Lopez-Anton, M A; Cieplik, M; Fierro, J L G; Martínez-Tarazona, M R

2012-05-15

The combustion of coal can result in trace elements, such as mercury, being released from power stations with potentially harmful effects for both human health and the environment. Research is ongoing to develop cost-effective and efficient control technologies for mercury removal from coal-fired power plants, the largest source of anthropogenic mercury emissions. A number of activated carbon sorbents have been demonstrated to be effective for mercury retention in coal combustion power plants. However, more economic alternatives need to be developed. Raw biomass gasification chars could serve as low-cost sorbents for capturing mercury since they are sub-products generated during a thermal conversion process. The aim of this study was to evaluate different biomass gasification chars as mercury sorbents in a simulated coal combustion flue gas. The results were compared with those obtained using a commercial activated carbon. Chars from a mixture of paper and plastic waste showed the highest retention capacity. It was found that not only a high carbon content and a well developed microporosity but also a high chlorine content and a high aluminium content improved the mercury retention capacity of biomass gasification chars. No relationship could be inferred between the surface oxygen functional groups and mercury retention in the char samples evaluated. Copyright © 2011 Elsevier Ltd. All rights reserved.

10. Power production from biomass II with special emphasis on gasification and pyrolysis R and DD

Energy Technology Data Exchange (ETDEWEB)

Sipilae, K.; Korhonen, M. [eds.] [VTT Energy, Espoo (Finland). Energy Production Technologies

1996-12-31

The Seminar on Power Production from Biomass II with special emphasis on gasification and pyrolysis R and DD, was organized by VTT Energy on 27 - 28 March 1995 in Espoo, Finland. All seminar speakers were invited in order to give a high-level overview of the achievements of biomass combustion, gasification and flash pyrolysis technologies. The sessions included presentations by all key industrial entrepreneurs in the field. The poster session was open to all groups interested. Globally bioenergy covers about 3 % of the primary energy consumption. Locally it has a significant role in many countries like in Finland, where bioenergy covers almost 15 % and peat 5 % of primary energy consumption. Today`s cost-effective heat and power production is based on industrial wood residues and spent cooking liquors in relatively large industrial units or municipal heating and power stations. Agricultural residues like straw and especially energy crops are becoming more interesting in co-utilization with other biomasses or fossil fuels. The seminar successfully displayed the status of present technologies as well as development targets for new gasification and flash pyrolysis technologies in the coming years. The many industrial participants showed that there are growing business possibilities in many countries all over the world. The proceedings include the most oral presentations given at the Seminar and also abstracts of poster presentations. (orig.)

11. Effect of fuel origin on synergy during co-gasification of biomass and coal in CO2.

Science.gov (United States)

Zhang, Yan; Zheng, Yan; Yang, Mingjun; Song, Yongchen

2016-01-01

The effect of fuel origin on synergy in coal/biomass blends during co-gasification has been assessed using a congruent-mass thermogravimetry analysis (TGA) method. Results revealed that synergy occurs when ash residuals are formed, followed by an almost complete gasification of biomass. Potassium species in biomass ash play a catalytic role in promoting gasification reactivity of coal char, which is a direct consequence of synergy during co-gasification. The SEM-EDS spectra provided conclusive evidence that the transfer of potassium from biomass to the surface of coal char occurs during co-pyrolysis/gasification. Biomass ash rich in silica eliminated synergy in coal/biomass blends but not to the extent of inhibiting the reaction rate of the blended chars to make it slower than that of separated ones. The best result in terms of synergy was concluded to be the combination of low-ash coal and K-rich biomass. Copyright © 2015 Elsevier Ltd. All rights reserved.

12. Thermal Pretreatment of Wood for Co-gasification/co-firing of Biomass and Coal

Energy Technology Data Exchange (ETDEWEB)

Wang, Ping [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States); Howard, Bret [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States); Hedges, Sheila [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States); Morreale, Bryan [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States); Van Essendelft, Dirk [National Energy Technology Lab. (NETL), Morgantown, WV (United States); Berry, David [National Energy Technology Lab. (NETL), Morgantown, WV (United States)

2013-10-29

Utilization of biomass as a co-feed in coal and biomass co-firing and co-gasification requires size reduction of the biomass. Reducing biomass to below 0.2 mm without pretreatment is difficult and costly because biomass is fibrous and compressible. Torrefaction is a promising thermal pretreatment process and has the advantages of increasing energy density, improving grindability, producing fuels with more homogenous compositions and hydrophobic behavior. Temperature is the most important factor for the torrefaction process. Biomass grindability is related to cell wall structure, thickness and composition. Thermal treatment such as torrefaction can cause chemical changes that significantly affect the strength of biomass. The objectives of this study are to understand the mechanism by which torrefaction improves the grindability of biomass and discuss suitable temperatures for thermal pretreatment for co-gasification/co-firing of biomass and coal. Wild cherry wood was selected as the model for this study. Samples were prepared by sawing a single tangential section from the heartwood and cutting it into eleven pieces. The samples were consecutively heated at 220, 260, 300, 350, 450 and 550⁰C for 0.5 hr under flowing nitrogen in a tube furnace. Untreated and treated samples were characterized for physical properties (color, dimensions and weight), microstructural changes by SEM, and cell wall composition changes and thermal behaviors by TGA and DSC. The morphology of the wood remained intact through the treatment range but the cell walls were thinner. Thermal treatments were observed to decompose the cell wall components. Hemicellulose decomposed over the range of ~200 to 300⁰C and resulted in weakening of the cell walls and subsequently improved grindability. Furthermore, wood samples treated above 300⁰C lost more than 39% in mass. Therefore, thermal pretreatment above the hemicelluloses decomposition temperature but below 300⁰C is probably sufficient to

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

Science.gov (United States)

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

2016-01-01

The major technical problems faced by stand-alone fluidized bed gasifiers (FBG) for waste-to gas applications are intrinsically related to the composition and physical properties of waste materials, such as RDF. The high quantity of ash and volatile material in RDF can provide a decrease in thermal output, create high ash clinkering, and increase emission of tars and CO2, thus affecting the operability for clean syngas generation at industrial scale. By contrast, a two-stage process which separates primary gasification and selective tar and ash conversion would be inherently more forgiving and stable. This can be achieved with the use of a separate plasma converter, which has been successfully used in conjunction with conventional thermal treatment units, for the ability to 'polish' the producer gas by organic contaminants and collect the inorganic fraction in a molten (and inert) state. This research focused on the performance analysis of a two-stage fluid bed gasification-plasma process to transform solid waste into clean syngas. Thermodynamic assessment using the two-stage equilibrium method was carried out to determine optimum conditions for the gasification of RDF and to understand the limitations and influence of the second stage on the process performance (gas heating value, cold gas efficiency, carbon conversion efficiency), along with other parameters. Comparison with a different thermal refining stage, i.e. thermal cracking (via partial oxidation) was also performed. The analysis is supported by experimental data from a pilot plant. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

14. 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.

15. Steam gasification of acid-hydrolysis biomass CAHR for clean syngas production.

Science.gov (United States)

Chen, Guanyi; Yao, Jingang; Yang, Huijun; Yan, Beibei; Chen, Hong

2015-03-01

Main characteristics of gaseous product from steam gasification of acid-hydrolysis biomass CAHR have been investigated experimentally. The comparison in terms of evolution of syngas flow rate, syngas quality and apparent thermal efficiency was made between steam gasification and pyrolysis in the lab-scale apparatus. The aim of this study was to determine the effects of temperature and steam to CAHR ratio on gas quality, syngas yield and energy conversion. The results showed that syngas and energy yield were better with gasification compared to pyrolysis under identical thermal conditions. Both high gasification temperature and introduction of proper steam led to higher gas quality, higher syngas yield and higher energy conversion efficiency. However, excessive steam reduced hydrogen yield and energy conversion efficiency. The optimal value of S/B was found to be 3.3. The maximum value of energy ratio was 0.855 at 800°C with the optimal S/B value. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

Energy Technology Data Exchange (ETDEWEB)

Raiko, R.; Haukka, P. [Tampere Univ. of Technology (Finland). Thermal Engineering

1995-11-01

This is the second phase of a project that started with examination of a gasification process for fuels containing high amounts of volatiles such as biomass. In the earlier phase of the project the gasification process was studied with the aid of computer models. Gas production with this gasification method is based mainly on rapid pyrolysis in dilute suspension flow enabling high solid to gas conversion. The two-stage approach eliminates char gasification as a limiting process step, and consequently, allows product temperature to be controlled by the kinetics of volatile reactions. A greater amount of enthalpy is made available for rapid pyrolysis through the total combustion of the residual char than is possible by partial oxidation. The main goal in the second year (1994) was to get experimental information on peat reactivity, main pyrolysis products and formation of nitrogen compounds in the early stages of peat pyrolysis in dilute pressurized flow conditions. These experiments were conducted using pressurized entrained flow reactor at VTT Energy (Jyvaeskylae). Preliminary experiments gave the result that pressure increase accelerates pyrolysis of peat at first (residence time < 100 ms), but this difference disappears gradually. The total amount of volatile matter does not seem to depend on pressure level. (author)

17. Biomass gasification to heat, electricity and biofuels. HighBio project publication

Energy Technology Data Exchange (ETDEWEB)

Lassi, U.; Wikman, B. (eds.)

2011-07-01

Renewable energy and the use of biomass in energy production promotes sustainable development and decreases the use of fossil fuels. Biomass, e.g. wood chips can be used in the production of heat and electricity, as well as being used as a biofuel component and novel product for the chemical industry. Efficient utilisation of biomass requires a high level of knowledge and the development of new processes to create a new way of thinking. In this process, international co-operation plays a significant role. The aim of the HighBio project was to produce new information on biomass gasification and the utilisation opportunities of product gas in biofuel and biochemicals production. The project was also aimed at studying utilisation properties of biogasification ashes in distributed energy production. Small-scaled CHP plants can be used for simultaneous heat and power production by gasifying wood chips and by burning energy intensive product gas. Compared with thermal combustion, particulate emissions from gasification are lower, which also contributes to the EU's ever tightening emission legislation. Several small and middle scale companies in the Northern part of Finland and Sweden have worked with biomass gasification, and during the project, the birth of new ones has been seen. In this development stage, researchers of the HighBio project have also been strongly involved. Increased use of renewable energy opens up new possibilities for entrepreneurship and the birth of new companies, especially in rural areas. In order to enable these opportunities, we need research data from the universities, novel innovations, and especially their successful commercialisation. The HighBio project has also contributed to tackling those challenges by arranging research seminars and meetings to companies and other interest groups, as well as by establishing research activities and collaborations. Regional collaboration combined with national and international research networks

18. 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

19. Comparison of steam gasification reactivity of algal and lignocellulosic biomass: influence of inorganic elements.

Science.gov (United States)

Hognon, Céline; Dupont, Capucine; Grateau, Maguelone; Delrue, Florian

2014-07-01

This study aims at comparing the steam gasification behaviour of two species of algal biomass (Chlamydomonas reinhardtii and Arthrospira platensis) and three species of lignocellulosic biomass (miscanthus, beech and wheat straw). Isothermal experiments were carried out in a thermobalance under chemical regime. Samples had very different contents in inorganic elements, which resulted in different reactivities, with about a factor of 5 between samples. For biomasses with ratio between potassium content and phosphorus and silicon content K/(Si+P) higher than one, the reaction rate was constant during most of the reaction and then slightly increased at high conversion. On the contrary, for biomasses with ratio K/(Si+P) lower than one, the reaction rate decreased along conversion. A simple kinetic model was proposed to predict these behaviours. Copyright © 2014 Elsevier Ltd. All rights reserved.

20. Kinetic model for hydrothermal biomass gasification; Kinetisches Modell der hydrothermalen Biomassevergasung

Energy Technology Data Exchange (ETDEWEB)

Kruse, A.; Keskin, M.; Faquir, M.; Dahmen, N. [Inst. fuer Technische Chemie, Forschungszentrum Karlsruhe (Germany)

2008-07-01

Hydrothermal biomass gasification is a promising technology to produce hydrogen from wet biomass, i.e. a water content of at least 50 %. This process allows the utilization of agricultural wastes or residuals from biochemical conversions. Since the reaction is highly kinetically controlled, it should be possible to optimimize gas yield and composition with respect to a maximum hydrogen yield. The paper describes the simulation of the process using a kinetic reaction model and experimental data from appropriate test facilities. Experiments were performed for several reactor types and a variety of model systems, like glucose, methane and hydroxy methyl furfural, that were identified as intermediate product for the hydrothermal hydrogen production. The influence of different additive 'catalysts' was tested. It was shown that the biomass composition has an important influence on the gas yield. Alkaline salts can be added to increase the yield. A fast heating and agitation of the biomass are also increasing the gas yield.

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

Directory of Open Access Journals (Sweden)

2011-03-01

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

2. Syngas production by two-stage method of biomass catalytic pyrolysis and gasification.

Science.gov (United States)

Xie, Qinglong; Kong, Sifang; Liu, Yangsheng; Zeng, Hui

2012-04-01

A two-stage technology integrated with biomass catalytic pyrolysis and gasification processes was utilized to produce syngas (H(2)+CO). In the presence of different nickel based catalysts, effects of pyrolysis temperature and gasification temperature on gas production were investigated. Experimental results showed that more syngas and char of high quality could be obtained at a temperature of 750°C in the stage of pyrolysis, and in the stage of gasification, pyrolysis char (produced at 750°C) reacted with steam and the maximum yield of syngas was obtained at 850°C. Syngas yield in this study was greatly increased compared with previous studies, up to 3.29Nm(3)/kg biomass. The pyrolysis process could be well explained by Arrhenius kinetic first-order rate equation. XRD analyses suggested that formation of Mg(0.4)Ni(0.6)O and increase of Ni(0) crystallite size were two main reasons for the deactivation of nickel based catalysts at higher temperature. Copyright © 2012 Elsevier Ltd. All rights reserved.

3. Investigation on the fates of vanadium and nickel during co-gasification of petroleum coke with biomass.

Science.gov (United States)

Li, Jiazhou; Wang, Xiaoyu; Wang, Bing; Zhao, Jiantao; Fang, Yitian

2018-02-16

4. Biomass steam gasification for production of SNG – Process design and sensitivity analysis

International Nuclear Information System (INIS)

Gröbl, Thomas; Walter, Heimo; Haider, Markus

2012-01-01

Highlights: ► A model for the SNG-production process from biomass to raw-SNG is prepared. ► A thermodynamic equilibrium model of the Biomass-Heatpipe-Reformer is developed. ► A sensitivity analysis on the most important operation parameters is carried out. ► Adopting the steam excess ratio a syngas ideally suitable for SNG production is generated. ► Thermodynamic equilibrium models are a useful tool for process design. -- Abstract: A process design for small-scale production of Substitute Natural Gas (SNG) by steam gasification of woody biomass is performed. In the course of this work, thermodynamic models for the novel process steps are developed and implemented into an already existing model library of commercial process simulation software IPSEpro. Mathematical models for allothermal steam gasification of biomass as well as for cleaning and methanation of product gas are provided by applying mass balances, energy balances and thermodynamic equilibrium equations. Using these models the whole process is integrated into the simulation software, a flowsheet for an optimum thermal integration of the single process steps is determined and energy savings are identified. Additionally, a sensitivity study is carried out in order to analyze the influence of various operation parameters. Their effects on amount and composition of the product gas and process efficiency are evaluated and discussed within this article.

5. Biomass gasification for electricity generation with internal combustion engines. Process efficiency

International Nuclear Information System (INIS)

Lesme-Jaén, René; Garcia Faure, Luis; Recio Recio, Angel; Oliva Ruiz, Luis; Pajarín Rodríguez, Juan; Revilla Suarez, Dennis

2015-01-01

Biomass is a renewable source of energy worldwide increased prospects for its potential and its lower environmental impact compared to fossil fuels. By processes and energy conversion technologies it is possible to obtain fuels in solid, liquid and gaseous form from any biomass. The biomass gasification is the thermal conversion thereof into a gas, which can be used for electricity production with the use of internal combustion engines with a certain level of efficiency, which depends on the characteristics of biomass and engines used. In this work the evaluation of thermal and overall efficiency of the gasification in Integrated Forestry Enterprise of Santiago de Cuba, designed to generate electricity from waste from the forest industry is presented. Is a downdraft gasifier reactor, COMBO-80 model and engine manufacturing Hindu (diesel) model Leyland modified to work with producer gas. The evaluation was carried out for different loads (electric power generated) engine from experimental measurements of flow and composition of the gas supplied to the engine. The results show that the motor operates with a thermal efficiency in the range of 20-32% with an overall efficiency between 12-25%. (full text)

6. 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.

7. Large-scale production of Fischer-Tropsch diesel from biomass. Optimal gasification and gas cleaning systems

International Nuclear Information System (INIS)

Boerrigter, H.; Van der Drift, A.

2004-12-01

The paper is presented in the form of copies of overhead sheets. The contents concern definitions, an overview of Integrated biomass gasification and Fischer Tropsch (FT) systems (state-of-the-art, gas cleaning and biosyngas production, experimental demonstration and conclusions), some aspects of large-scale systems (motivation, biomass import) and an outlook

8. Economic viability of the construction and operation of a biomass gasificator for poultry houses heating

Energy Technology Data Exchange (ETDEWEB)

Zanatta, Fabio Luiz; Silva, Jadir Nogueira da; Tinoco, Ilda de Fatima Ferreira; Martin, Samuel; Melo, Lucas D.; Bueno, Mateus [Universidade Federal de Vicosa (DEA/UFV), MG (Brazil). Dept. de Engenharia Agricola], E-mail: fzanatta@vicosa.ufv.br

2008-07-01

In all poultry farms, at least in the first days of life of the chicken, it is necessary to heat the environment to obtain a good development of the chicken and good economics results. However, this additional heat generation is sometimes neglected or not well executed, because of the costs that this practice could bring. This research has the objective of analyze the costs of construction and operation of a Biomass Gasificator for Poultry Houses Heating in comparison with a direct furnace system. The fuel used in both systems was firewood of eucalyptus. For so much, economic analyzes was make considering the costs of the gasification systems implementation in substitution of the traditional system used in the company (direct furnace system). For the viability the adopted method was the partial budget and the complementary investments were analyzed through the cash flow elaboration and of determination of indicator of economic feasibility. (author)

9. Optical Absorption Spectroscopy for Gas Analysis in Biomass Gasification

DEFF Research Database (Denmark)

Grosch, Helge

important gas species of the low-temperature circulating fluidized bed gasifier. At first, a special gas cell,the hot gas flow cell (HGC), was build up and veried. In this custom-made gas cell, the optical properties, the so-called absorption cross-sections, of the most important sulfur and aromatic...... compounds were determined in laboratory experiments. By means of the laboratory results and spectroscopic databases,the concentrations of the major gas species and the aromatic compounds phenol and naphthalene were determined in extraction and in-situ measurements....

10. [Transformation of sulfur forms during coal pyrolysis and partial gasification in a fixed bed reactor].

Science.gov (United States)

Li, Bin; Cao, Yan; Zhang, Jianmin; Huang, Jiejie; Wang, Yang; Chen, Fuyan

2003-03-01

The development of various process to the pre-desulfurization of coal was drawn more attention. In present study, the transformation of sulfur forms of three different ranks high sulfur coals during coal pyrolysis and partial gasification were investigated in a fixed bed reactor. The sulfur and carbon content analysis of original coal and coal char produced were determined by LECO SC-444 and wet chemical analysis according to Sugawara's method. The results showed that half of inorganic sulfur and partial of organic sulfur were removed during coal pyrolysis. And the sulfur removal was much more than carbon during pyrolysis process; and the sulfur in the coal char, especially the sulfide sulfur was removed completely during partial gasification process for both Datong coal and Xishan coal, the degree of sulfide sulfur removal could be increased with increasing temperature. At the same time, the results of Yima coal showed that the effect of fixed-sulfur by alkaline metals increased when the temperature was higher than 700 degrees C, which attribute to the increase of the fixed sulfur reaction rate and the decrease of mass-transfer limitation.

11. Thermodynamic Analysis of a Power Plant Integrated with Fogging Inlet Cooling and a Biomass Gasification

Directory of Open Access Journals (Sweden)

Hassan Athari

2015-01-01

Full Text Available Biomass energy and especially biofuels produced by biomass gasification are clean and renewable options for power plants. Also, on hot days the performance of gas turbines decreases substantially, a problem that can be mitigated by fog cooling. In the present paper, a biomass-integrated fogging steam injected gas turbine cycle is analyzed with energy and exergy methods. It is observed that (1 increasing the compressor pressure ratio raises the air flow rate in the plant but reduces the biomass flow rate; (2 increasing the gas turbine inlet temperature decreases the air and biomass flow rates; (3 increasing the compressor pressure ratio raises the energy and exergy efficiencies, especially at lower pressure ratios; (4 increasing the gas turbine inlet temperature raises both efficiencies; and (5 overspray increases the energy efficiency and net cycle power slightly. The gas turbine exhibits the highest exergy efficiency of the cycle components and the combustor the lowest. A comparison of the cycle with similar cycles fired by natural gas and differently configured cycles fueled by biomass shows that the cycle with natural gas firing has an energy efficiency 18 percentage points above the biomass fired cycle, and that steam injection increases the energy efficiency about five percentage points relative to the cycle without steam injection. Also, the influence of steam injection on energy efficiency is more significant than fog cooling.

12. Analysis and comparison of biomass pyrolysis/gasification condensates: Final report

Energy Technology Data Exchange (ETDEWEB)

Elliott, D.C.

1986-06-01

This report provides results of chemical and physical analysis of condensates from eleven biomass gasification and pyrolysis systems. The samples were representative of the various reactor configurations being researched within the Department of Energy, Biomass Thermochemical Conversion program. The condensates included tar phases and aqueous phases. The analyses included gross compositional analysis (elemental analysis, ash, moisture), physical characterization (pour point, viscosity, density, heat of combustion, distillation), specific chemical analysis (gas chromatography/mass spectrometry, infrared spectrophotometry, proton and carbon-13 nuclear magnetic resonance spectrometry) and biological activity (Ames assay and mouse skin tumorigenicity tests). These results are the first step of a longer term program to determine the properties, handling requirements, and utility of the condensates recovered from biomass gasification and pyrolysis. The analytical data demonstrates the wide range of chemical composition of the organics recovered in the condensates and suggests a direct relationship between operating temperature and chemical composition of the condensates. A continuous pathway of thermal degradation of the tar components as a function of temperature is proposed. Variations in the chemical composition of the organic components in the tars are reflected in the physical properties of tars and phase stability in relation to water in the condensate. The biological activity appears to be limited to the tars produced at high temperatures. 56 refs., 25 figs., 21 tabs.

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

Energy Technology Data Exchange (ETDEWEB)

Archie Robertson

2003-04-17

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

14. Design of novel DME/methanol synthesis plants based on gasification of biomass

OpenAIRE

Clausen, Lasse Røngaard; Elmegaard, Brian; Houbak, Niels

2011-01-01

A way to reduce the CO2 emissions from the transportation sector is by increasing the use of biofuels in the sector. DME and methanol are two such biofuels, which can be synthesized from biomass, by use of gasification followed by chemical synthesis. This method of producing biofuels is shown to be more cost-effective, less energy consuming and less CO2 emitting, when considering the total well-to-wheel processes, than first generation biofuels and second generation ethanol produced by biolog...

15. Char-recirculation biomass gasification system--a site-specific feasibility study

International Nuclear Information System (INIS)

Purdy, K.R.; Kerr, C.P.; Hensley, B.D.

1991-01-01

A site-specific feasibility study was conducted for a char-recirculation biomass gasification plant which would dispose of the chippable solid residues of the area sawmills. The plant would receive green hardwood chips and convert them into active charcoal while producing process steam and electrical power. An economic analysis was performed on the basis of not-for-profit operation, marketing crushed active charcoal to a broker at a discounted price, and displacing purchased electric power. Given a market for the active charcoal, the plant was judged to be economically viable

16. Design, Optimization and Energetic Efficiency of Producing Hydrogen-Rich Gas from Biomass Steam Gasification

Directory of Open Access Journals (Sweden)

Po-Chih Kuo

2014-12-01

Full Text Available In this article, the conceptual design of biomass steam gasification (BSG processes using raw oil palm (ROP and torrefied oil palm (TOP are examined in an Aspen Plus simulator. Through thermodynamic analysis, it is verified that the BSG process with torrefied feedstock can effectively enhance the hydrogen yield. When the heat recovery design is added into the BSG process, the system energetic efficiency (SEE is significantly improved. Finally, an optimization algorithm with respect to SEE and hydrogen yield is solved, and the optimum operating conditions are validated by simulations.

17. Experimental investigation on an entrained flow type biomass gasification system using coconut coir dust as powdery biomass feedstock.

Science.gov (United States)

Senapati, P K; Behera, S

2012-08-01

Based on an entrained flow concept, a prototype atmospheric gasification system has been designed and developed in the laboratory for gasification of powdery biomass feedstock such as rice husks, coconut coir dust, saw dust etc. The reactor was developed by adopting L/D (height to diameter) ratio of 10, residence time of about 2s and a turn down ratio (TDR) of 1.5. The experimental investigation was carried out using coconut coir dust as biomass feedstock with a mean operating feed rate of 40 kg/h The effects of equivalence ratio in the range of 0.21-0.3, steam feed at a fixed flow rate of 12 kg/h, preheat on reactor temperature, product gas yield and tar content were investigated. The gasifier could able to attain high temperatures in the range of 976-1100 °C with gas lower heating value (LHV) and peak cold gas efficiency (CGE) of 7.86 MJ/Nm3 and 87.6% respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

18. 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.

19. 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 t echnoeconomic 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.

20. Aerosol formation and effect in biomass combustion and gasification

International Nuclear Information System (INIS)

Strand, Michael; Lillieblad, Lena; Sanati, Mehri; Pagels, Joakim; Szpila, Aneta; Boghard, Mats; Rissler, Jenny; Swietlicki, Erik

2005-09-01

The fine particle composition as analysed with PIXE and IC, was dominated by potassium, sulphur and chlorine. In some cases there was also a substantial concentration of zinc in the fine mode particles. The proposed mechanism for formation of the fine mode is homogenous chemical reactions to form potassium sulphate, which nucleates to form a fine particle mode at high temperatures The concentration profile of zinc indicates that zinc-containing species may form particles by gas-to-particle conversion prior to the nucleation of potassium sulphate. As the flue gas temperature decrease below 650 deg C potassium chloride will condense on the surfaces of the previously formed particles. As the temperature descends further, other more volatile components such as Pb and heavy hydrocarbons will condense. The coarse particle number concentration varied between 100-10,000 particles/cm 3 , and the mass concentration varied between 4-87 mg/cm 3 , with the highest concentrations for the high load cases. The coarse mode particles were mainly composed of calcium and manganese in addition to potassium, sulphur and chlorine. The proposed mechanism for inception of the coarse particle mode was fragmentation/dispersion of refractory material from the burning char or from the residual ash in the bed. The ratios of the potentially volatile elements potassium, sulphur and chlorine, were similar in the fine and the coarse mode, indicating the material had the same origin in both modes. The presence of the volatile components may be explained by non-complete vaporisation, chemical surface reactions, and re-entrainment of deposited particles or by coagulation of fine particles. However, neither of the proposed mechanisms can give a conclusive explanation to the composition of the coarse mode, i.e. the high concentration potentially volatile elements

1. Aerosol formation and effect in biomass combustion and gasification

Energy Technology Data Exchange (ETDEWEB)

Strand, Michael; Lillieblad, Lena; Sanati, Mehri [Vaexjoe Univ. (Sweden). Bioenergy Technology; Pagels, Joakim; Szpila, Aneta; Boghard, Mats [Lund Univ. (Sweden). Div. of Ergonomics and Aerosol Technology; Rissler, Jenny; Swietlicki, Erik [Lund Univ. (Sweden). Div. of Nuclear Physics

2005-09-01

The fine particle composition as analysed with PIXE and IC, was dominated by potassium, sulphur and chlorine. In some cases there was also a substantial concentration of zinc in the fine mode particles. The proposed mechanism for formation of the fine mode is homogenous chemical reactions to form potassium sulphate, which nucleates to form a fine particle mode at high temperatures The concentration profile of zinc indicates that zinc-containing species may form particles by gas-to-particle conversion prior to the nucleation of potassium sulphate. As the flue gas temperature decrease below 650 deg C potassium chloride will condense on the surfaces of the previously formed particles. As the temperature descends further, other more volatile components such as Pb and heavy hydrocarbons will condense. The coarse particle number concentration varied between 100-10,000 particles/cm{sup 3}, and the mass concentration varied between 4-87 mg/cm{sup 3}, with the highest concentrations for the high load cases. The coarse mode particles were mainly composed of calcium and manganese in addition to potassium, sulphur and chlorine. The proposed mechanism for inception of the coarse particle mode was fragmentation/dispersion of refractory material from the burning char or from the residual ash in the bed. The ratios of the potentially volatile elements potassium, sulphur and chlorine, were similar in the fine and the coarse mode, indicating the material had the same origin in both modes. The presence of the volatile components may be explained by non-complete vaporisation, chemical surface reactions, and re-entrainment of deposited particles or by coagulation of fine particles. However, neither of the proposed mechanisms can give a conclusive explanation to the composition of the coarse mode, i.e. the high concentration potentially volatile elements.

2. Biomass gasification integrated with a solid oxide fuel cell and Stirling engine

International Nuclear Information System (INIS)

Rokni, Masoud

2014-01-01

An integrated gasification solid oxide fuel cell (SOFC) and Stirling engine for combined heat and power application is analyzed. The target for electricity production is 120 kW. Woodchips are used as gasification feedstock to produce syngas, which is then used to feed the SOFC stacks for electricity production. Unreacted hydrocarbons remaining after the SOFC are burned in a catalytic burner, and the hot off-gases from the burner are recovered in a Stirling engine for electricity and heat production. Domestic hot water is used as a heat sink for the Stirling engine. A complete balance-of-plant is designed and suggested. Thermodynamic analysis shows that a thermal efficiency of 42.4% based on the lower heating value (LHV) can be achieved if all input parameters are selected conservatively. Different parameter studies are performed to analyze the system behavior under different conditions. The analysis shows that the decreasing number of stacks from a design viewpoint, indicating that plant efficiency decreases but power production remains nearly unchanged. Furthermore, the analysis shows that there is an optimum value for the utilization factor of the SOFC for the suggested plant design with the suggested input parameters. This optimum value is approximately 65%, which is a rather modest value for SOFC. In addition, introducing a methanator increases plant efficiency slightly. If SOFC operating temperature decreases due to new technology then plant efficiency will slightly be increased. Decreasing gasifier temperature, which cannot be controlled, causes the plant efficiency to increase also. - Highlights: • Design of integrated gasification with solid oxide fuel and Stirling engine. • Important plant parameters study. • Plant running on biomass with and without methanator. • Thermodynamics of integrated gasification SOFC-Stirling engine plants

3. Catalytic hydrothermal gasification of biomass for the production of synthetic natural gas[Dissertation 17100

Energy Technology Data Exchange (ETDEWEB)

Waldner, M. H.

2007-07-01

Energy from biomass is a CO{sub 2} neutral, sustainable form of energy. Anaerobic digestion is an established technology for converting biomass to biogas, which contains around 60% methane, besides CO{sub 2} and various contaminants. Most types of biomass contain material that cannot be digested; in woody biomass, this portion is particularly high. Therefore, conventional anaerobic digestion is not suited for the production of biogas from woody biomass. While wood is already being converted to energy by conventional thermal methods (gasification with subsequent methanation), dung, manure, and sewage sludge represent types of biomass whose energy potential remains largely untapped (present energetic use of manure in Switzerland: 0.4%). Conventional gas phase processes suffer from a low efficiency due to the high water content of the feed (enthalpy of vaporization). An alternative technology is the hydrothermal gasification: the water contained within the biomass serves as reaction medium, which at high pressures of around 30 MPa turns into a supercritical fluid that exhibits apolar properties. Under these conditions, tar precursors, which cause significant problems in conventional gasification, can be solubilized and gasified. The need to dry the biomass prior to gasification is obsolete, and as a consequence high thermal process efficiencies (65 - 70%) are possible. Due to their low solubility in supercritical water, the inorganics that are present in the biomass (up to 20 wt % of the dry matter of manure) can be separated and further used as fertilizer. The biomass is thus not only converted into an energy carrier, but it allows valuable substances contained in the biomass to be extracted and re-used. Furthermore, the process can be used for aqueous waste stream destruction. The aim of this project at the Paul Scherrer Institute was to develop a catalytic process that demonstrates the gasification of wet biomass to synthetic natural gas (SNG) in a continuously

4. Biomass low-temperature gasification in a rotary reactor prior to cofiring of syngas in power boilers

International Nuclear Information System (INIS)

Ostrowski, Piotr; Maj, Izabella; Kalisz, Sylwester; Polok, Michał

2017-01-01

Highlights: • An innovative method of gasification with use of flue gas was investigated. • Gasification temperature ranging from 350 °C was considered. • Discussed gasification unit is connected to a power boiler. • Syngas with combustible components is recirculated to the boiler. • Wide range of biomass and waste fuels can be used as a feedstock. - Abstract: The paper presents results of the investigation of an innovative biomass and alternative fuel low-temperature gasification method before co-firing in industrial or power plant boilers. Before running industrial-size installation, laboratory tests were carried out to determine usability of alternative fuels to low-temperature gasification process. Tests were conducted in a laboratory reactor designed and constructed specifically for this purpose. The experimental stand enables recording of the weight loss of a sample and syngas composition. The process occurs for a fuel sample of a constant weight and known granulation and with a flue gas of known composition used as a gasifying agent. The aim of the laboratory research was to determine the usability of selected biomass fuel for indirect co-firing in power boilers and to build a knowledge base for industrial-size process by defining the process kinetics (time for fuel to remain in the reactor), recommended fuel granulation and process temperature. Presented industrial-size gasification unit has been successfully built in Marcel power plant in Radlin town, Poland. It consist an innovative rotary gasification reactor. Gasification process takes place with use of flue gas from coal and coke-oven fired boiler as a gasifying agent with recirculation of resulting gas (syngas) with combustible components: CO, H 2 , CH 4 . C n H m to the boiler’s combustion chamber. The construction of the reactor allows the use of a wide range of fuels (biomass, industrial waste and municipal waste). This paper presents the results of the reactor tests using coniferous

5. 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

6. Environmental assessment of gasification technology for biomass conversion to energy in comparison with other alternatives

DEFF Research Database (Denmark)

Nguyen, T Lan T; Hermansen, John Erik; Nielsen, Rasmus Glar

2013-01-01

This paper assesses the environmental performance of biomass gasification for electricity production based on wheat straw and compares it with that of alternatives such as straw-fired electricity production and fossil fuel-fired electricity production. In the baseline simulation, we assume...... that the combustion of biomass and fossil fuel references for electricity production takes place in a combined heat and power plant, but as a sensitivity analysis, we also consider combustion in a condensing mode power plant where only electricity is produced. Our results show that the production of 1 k......Wh of electricity from straw through gasification would lead to a global warming potential of 0.08 kg CO2e, non-renewable energy use of 0.2 MJ primary, acidification of 1.3 g SO2e, respiratory inorganics of 0.08 g PM2.5e and eutrophication potential of -1.9 g NO3e. The production of electricity from straw based...

7. Modeling and Assessment of a Biomass Gasification Integrated System for Multigeneration Purpose

Directory of Open Access Journals (Sweden)

2016-01-01

Full Text Available The use of biomass due to the reduction in greenhouse gas emissions and environmental impacts has attracted many researchers’ attention in the recent years. Access to an energy conversion system which is able to have the optimum performance for applying valuable low heating value fuels has been considered by many practitioners and scholars. This paper focuses on the accurate modeling of biomass gasification process and the optimal design of a multigeneration system (heating, cooling, electrical power, and hydrogen as energy carrier to take the advantage of this clean energy. In the process of gasification modeling, a thermodynamic equilibrium model based on Gibbs energy minimization is used. Also, in the present study, a detailed parametric analysis of multigeneration system for undersigning the behavior of objective functions with changing design parameters and obtaining the optimal design parameters of the system is done as well. The results show that with exergy efficiency as an objective function this parameter can increase from 19.6% in base case to 21.89% in the optimized case. Also, for the total cost rate of system as an objective function it can decrease from 154.4 \$/h to 145.1 \$/h.

8. Tar analysis from biomass gasification by means of online fluorescence spectroscopy

Science.gov (United States)

Baumhakl, Christoph; Karellas, Sotirios

2011-07-01

Optical methods in gas analysis are very valuable mainly due to their non-intrusive character. That gives the possibility to use them for in-situ or online measurements with only optical intervention in the measurement volume. In processes like the gasification of biomass, it is of high importance to monitor the gas quality in order to use the product gas in proper machines for energy production following the restrictions in the gas composition but also improving its quality, which leads to high efficient systems. One of the main problems in the biomass gasification process is the formation of tars. These higher hydrocarbons can lead to problems in the operation of the energy system. Up to date, the state of the art method used widely for the determination of tars is a standardized offline measurement system, the so-called "Tar Protocol". The aim of this work is to describe an innovative, online, optical method for determining the tar content of the product gas by means of fluorescence spectroscopy. This method uses optical sources and detectors that can be found in the market at low cost and therefore it is very attractive, especially for industrial applications where cost efficiency followed by medium to high precision are of high importance.

9. Preparation and Characterization of Malaysian Dolomites as a Tar Cracking Catalyst in Biomass Gasification Process

Directory of Open Access Journals (Sweden)

M. A. A. Mohammed

2013-01-01

Full Text Available Three types of local Malaysian dolomites were characterized to investigate their suitability for use as tar-cracking catalysts in the biomass gasification process. The dolomites were calcined to examine the effect of the calcination process on dolomite’s catalytic activity and properties. The modifications undergone by dolomites consequent to thermal treatment were investigated using various analytical methods. Thermogravimetric and differential thermal analyses indicated that the dolomites underwent two stages of decomposition during the calcination process. The X-ray diffraction and Fourier-transform infrared spectra analyses showed that thermal treatment of dolomite played a significant role in the disappearance of the CaMg(CO32 phase, producing the MgO-CaO form of dolomite. The scanning electron microscopy microphotographs of dolomite indicated that the morphological properties were profoundly affected by the calcination process, which led to the formation of a highly porous surface with small spherical particles. In addition, the calcination of dolomite led to the elimination of carbon dioxide and increases in the values of the specific surface area and average pore diameter, as indicated by surface area analysis. The results showed that calcined Malaysian dolomites have great potential to be applied as tar-cracking catalysts in the biomass gasification process based on their favorable physical properties.

10. 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.

11. Technoeconomic analysis of a methanol plant based on gasification of biomass and electrolysis of water

International Nuclear Information System (INIS)

Clausen, Lasse R.; Houbak, Niels; Elmegaard, Brian

2010-01-01

Methanol production process configurations based on renewable energy sources have been designed. The processes were analyzed in the thermodynamic process simulation tool DNA. The syngas used for the catalytic methanol production was produced by gasification of biomass, electrolysis of water, CO 2 from post-combustion capture and autothermal reforming of natural gas or biogas. Underground gas storage of hydrogen and oxygen was used in connection with the electrolysis to enable the electrolyser to follow the variations in the power produced by renewables. Six plant configurations, each with a different syngas production method, were compared. The plants achieve methanol exergy efficiencies of 59-72%, the best from a configuration incorporating autothermal reforming of biogas and electrolysis of water for syngas production. The different processes in the plants are highly heat integrated, and the low-temperature waste heat is used for district heat production. This results in high total energy efficiencies (∼90%) for the plants. The specific methanol costs for the six plants are in the range 11.8-25.3 Euro /GJ exergy . The lowest cost is obtained by a plant using electrolysis of water, gasification of biomass and autothermal reforming of natural gas for syngas production.

12. A comparative study of biomass integrated gasification combined cycle power systems: Performance analysis.

Science.gov (United States)

Zang, Guiyan; Tejasvi, Sharma; Ratner, Albert; Lora, Electo Silva

2018-05-01

The Biomass Integrated Gasification Combined Cycle (BIGCC) power system is believed to potentially be a highly efficient way to utilize biomass to generate power. However, there is no comparative study of BIGCC systems that examines all the latest improvements for gasification agents, gas turbine combustion methods, and CO 2 Capture and Storage options. This study examines the impact of recent advancements on BIGCC performance through exergy analysis using Aspen Plus. Results show that the exergy efficiency of these systems is ranged from 22.3% to 37.1%. Furthermore, exergy analysis indicates that the gas turbine with external combustion has relatively high exergy efficiency, and Selexol CO 2 removal method has low exergy destruction. Moreover, the sensitivity analysis shows that the system exergy efficiency is more sensitive to the initial temperature and pressure ratio of the gas turbine, whereas has a relatively weak dependence on the initial temperature and initial pressure of the steam turbine. Copyright © 2018 Elsevier Ltd. All rights reserved.

13. Analysis and co-ordination of the activities concerning gasification of biomass. Summary country report, Denmark and Norway

International Nuclear Information System (INIS)

Stoholm, P.; Olsen, A.

1996-11-01

The analysis summarises the coordination of activities concerning the gasification of biomass in Denmark and Norway. The total quantity of available biomass for energy production in Denmark corresponds to ca. 115 PJ of which ca. 40% is utilized - and this constitutes ca. 6% of the country's total energy consumption. The resulting energy from biomass is currently mostly used for heating purposes utilizing small wood/straw household or farm stoves in addition to ca. 100 district heating systems. There is a tendency to use biomass fuels for electric power production as in the case of all major waste incineration plants and about 10 fully or partly wood/straw-fired cogeneration plants which are found within the range of 2 -20 MWe. A table shows details of all Danish biomass gasification plants and information is given on the types of biomass, under the titles of residue products and energy crops, most relevant to energy production in Denmark. Data is presented on the consumption of renewable energy in Denmark, recalculated in fuel equivalents, and Danish national energy policy and related legislation are described. Information on Norway's use of biomass as fuel is given under the headings of primary consumption, biomass sources and use, legislation, and brief evaluations of commercial gasification plants, pilot and demonstration plants, and laboratory plants and studies. It has recently been decided to speed up the development of small-scale gasification plants for combined heat and electricity production using biomass as fuel in Denmark. Total Norwegian energy consumption is 25% higher than Denmark's, and biomass fuels cover only 3.6% of this. (ARW) 32 refs

14. Economics of biomass energy utilization in combustion and gasification plants: effects of logistic variables

International Nuclear Information System (INIS)

Caputo, Antonio C.; Palumbo, Mario; Pelagagge, Pacifico M.; Scacchia, Federica

2005-01-01

The substitution of conventional fossil fuels with biomass for energy production results both in a net reduction of greenhouse gases emissions and in the replacement of non-renewable energy sources. However, at present, generating energy from biomass is rather expensive due to both technological limits related to lower conversion efficiencies, and logistic constraints. In particular, the logistics of biomass fuel supply is likely to be complex owing to the intrinsic feedstock characteristics, such as the limited period of availability and the scattered geographical distribution over the territory. In this paper, the economical feasibility of biomass utilization for direct production of electric energy by means of combustion and gasification-conversion processes, has been investigated and evaluated over a capacity range from 5 to 50 MW, taking into account total capital investments, revenues from energy sale and total operating costs, also including a detailed evaluation of logistic costs. Moreover, in order to evaluate the impact of logistics on the bio-energy plants profitability, the effects of main logistic variables such as specific vehicle transport costs, vehicles capacity, specific purchased biomass costs and distribution density, have been examined. Finally, a mapping of logistic constraints on plant profitability in the specified capacity range has been carried out

15. Biomass pyrolysis/gasification for product gas production: the overall investigation of parametric effects

International Nuclear Information System (INIS)

Chen, G.; Andries, J.; Luo, Z.; Spliethoff, H.

2003-01-01

The conventional biomass pyrolysis/gasification process for production of medium heating value gas for industrial or civil applications faces two disadvantages, i.e. low gas productivity and the accompanying corrosion of downstream equipment caused by the high content of tar vapour contained in the gas phase. The objective of this paper is to overcome these disadvantages, and therefore, the effects of the operating parameters on biomass pyrolysis are investigated in a laboratory setup based on the principle of keeping the heating value of the gas almost unchanged. The studied parameters include reaction temperature, residence time of volatile phase in the reactor, physico-chemical pretreatment of biomass particles, heating rate of the external heating furnace and improvement of the heat and mass transfer ability of the pyrolysis reactor. The running temperature of a separate cracking reactor and the geometrical configuration of the pyrolysis reactor are also studied. However, due to time limits, different types of catalysts are not used in this work to determine their positive influences on biomass pyrolysis behaviour. The results indicate that product gas production from biomass pyrolysis is sensitive to the operating parameters mentioned above, and the product gas heating value is high, up to 13-15 MJ/N m 3

16. Hydrogen-Rich Gas Production by Cogasification of Coal and Biomass in an Intermittent Fluidized Bed

Directory of Open Access Journals (Sweden)

Li-Qun Wang

2013-01-01

Full Text Available This paper presents the experimental results of cogasification of coal and biomass in an intermittent fluidized bed reactor, aiming to investigate the influences of operation parameters such as gasification temperature (T, steam to biomass mass ratio (SBMR, and biomass to coal mass ratio (BCMR on hydrogen-rich (H2-rich gas production. The results show that H2-rich gas free of N2 dilution is produced and the H2 yield is in the range of 18.25~68.13 g/kg. The increases of T, SBMR, and BCMR are all favorable for promoting the H2 production. Higher temperature contributes to higher CO and H2 contents, as well as H2 yield. The BCMR has a weak influence on gas composition, but the yield and content of H2 increase with BCMR, reaching a peak at the BCMR of 4. The H2 content and yield in the product gas increase with SBMR, whilst the content of CO increases first and then decreases correspondingly. At a typical case, the relative linear sensitivity coefficients of H2 production efficiency to T, SBMR, and BCMR were calculated. The results reveal that the order of the influence of the operation parameters on H2 production efficiency is T > SBMR > BCMR.

17. Hydrogen-rich gas production by cogasification of coal and biomass in an intermittent fluidized bed.

Science.gov (United States)

Wang, Li-Qun; Chen, Zhao-Sheng

2013-01-01

This paper presents the experimental results of cogasification of coal and biomass in an intermittent fluidized bed reactor, aiming to investigate the influences of operation parameters such as gasification temperature (T), steam to biomass mass ratio (SBMR), and biomass to coal mass ratio (BCMR) on hydrogen-rich (H2-rich) gas production. The results show that H2-rich gas free of N2 dilution is produced and the H2 yield is in the range of 18.25~68.13 g/kg. The increases of T, SBMR, and BCMR are all favorable for promoting the H2 production. Higher temperature contributes to higher CO and H2 contents, as well as H2 yield. The BCMR has a weak influence on gas composition, but the yield and content of H2 increase with BCMR, reaching a peak at the BCMR of 4. The H2 content and yield in the product gas increase with SBMR, whilst the content of CO increases first and then decreases correspondingly. At a typical case, the relative linear sensitivity coefficients of H2 production efficiency to T, SBMR, and BCMR were calculated. The results reveal that the order of the influence of the operation parameters on H2 production efficiency is T > SBMR > BCMR.

18. Ab initio calculations and kinetic modeling of thermal conversion of methyl chloride: implications for gasification of biomass

DEFF Research Database (Denmark)

Singla, Mallika; Rasmussen, Morten Lund; Hashemi, Hamid

2018-01-01

. In the present work, the thermal conversion of CH3Cl under gasification conditions was investigated. A detailed chemical kinetic model for pyrolysis and oxidation of methyl chloride was developed and validated against selected experimental data from the literature. Key reactions of CH2Cl with O2 and C2H4......Limitations in current hot gas cleaning methods for chlorine species from biomass gasification may be a challenge for end use such as gas turbines, engines, and fuel cells, all requiring very low levels of chlorine. During devolatilization of biomass, chlorine is released partly as methyl chloride...... in low-temperature gasification. The present work illustrates how ab initio theory and chemical kinetic modeling can help to resolve emission issues for thermal processes in industrial scale....

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

Energy Technology Data Exchange (ETDEWEB)

Zhen Fan

2006-05-30

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

20. Bioenergy originating from biomass combustion in a fluidized bed

Energy Technology Data Exchange (ETDEWEB)

Crujeira, T.; Gulyurtlu, I.; Lopes, H.; Abelha, P.; Cabrita, I. [INETI/DEECA, Lisboa (Portugal)

2008-07-01

Bioenergy could significantly contribute to reducing and controlling greenhouse emissions (GHG) and to replace fossil fuels in large power plants. Although the use of biomass, originating from forests, could be beneficial, particularly in preventing fires, there are obstacles to achieve a sustainable supply chain of biomass in most European countries. In addition, there are also technical barriers as requirements of biomass combustion may differ from those of coal, which could mean significant retrofitting of existing installations. The combustion behaviour of different biomass materials were studied on a pilot fluidised bed combustor, equipped with two cyclones for particulate matter removal. The gaseous pollutants leaving the stack were sampled under isokinetic conditions for particulate matter, chlorine compounds, heavy metals and dioxins and furans (PCDD/F). The results obtained indicated that the combustion of these materials did not present any operational problem, although for temperatures above 800{sup o}C, bed agglomeration could be observed for all biomass materials studied. Most of the combustion of biomass, contrary to what is observed for coal, takes place in the riser where the temperature was as much as 150{sup o}C above that of the bed. Stable combustion conditions were achieved as well as high combustion efficiency. When compared with the emissions of bituminous coal, the most used fossil fuel, the emissions of CO and SO2 were found to be lower and NOx emissions were similar to those of coal. HCl and PCDD/F could be considerable with biomasses containing high chlorine levels, as in the case of straw. It was observed that the nature of ash could give rise serious operating problems.

1. Fossil fuel savings, carbon emission reduction and economic attractiveness of medium-scale integrated biomass gasification combined cycle cogeneration plants

Directory of Open Access Journals (Sweden)

Kalina Jacek

2012-01-01

Full Text Available The paper theoretically investigates the system made up of fluidized bed gasifier, SGT-100 gas turbine and bottoming steam cycle. Different configurations of the combined cycle plant are examined. A comparison is made between systems with producer gas (PG and natural gas (NG fired turbine. Supplementary firing of the PG in a heat recovery steam generator is also taken into account. The performance of the gas turbine is investigated using in-house built Engineering Equation Solver model. Steam cycle is modeled using GateCycleTM simulation software. The results are compared in terms of electric energy generation efficiency, CO2 emission and fossil fuel energy savings. Finally there is performed an economic analysis of a sample project. The results show relatively good performance in the both alternative configurations at different rates of supplementary firing. Furthermore, positive values of economic indices were obtained. [Acknowledgements. This work was carried out within the frame of research project no. N N513 004036, titled: Analysis and optimization of distributed energy conversion plants integrated with gasification of biomass. The project is financed by the Polish Ministry of Science.

2. Thermal gasification of biomass technology development in the U.S.A

Energy Technology Data Exchange (ETDEWEB)

Babu, S.P. [Inst. of Gas Technology, Des Plaines, IL (United States); Bain, R.L.; Craig, K.R. [National Renewable Energy Laboratory, Golden, CO (United States)

1996-12-31

In the U.S.A., the widely recognized importance of biomass utilization in controlling carbon build-up in the biosphere and the potential benefit of creating new industries associated with new job opportunities, particularly in the rural areas, have added impetus to the development and commercialization of advanced biomass energy conversion methods. Recent analyses and evaluations have shown that many short rotation energy crops (SREC) produce significant net-energy (i.e., energy yield greater than the energy input for plant growth). SREC such as willow, poplar, and miscanthus may yield up to 20 dry tonnes/yr/ha/year of biomass feedstocks, some with about 20 % moisture, after the third year of plantation. Implementation by U.S. EPA of the recent Clean Water Act Federal Biosolids Rules specified as Code 40 of Federal Register 503, should make available large quantities of high nitrogen content, pathogen-free municipal sludges ideally suited as an inexpensive source of organic fertiliser, thus improving the economics of SREC. The concept of herbaceous SREC can be further augmented when value-added byproducts, such as cattle feed, could be produced along with biomass energy feedstocks. Since 1990, there has been renewed interest in the United States in developing advanced power-generating cycles utilizing biomass gasification. The advanced systems have the potential for higher generation efficiencies, 35 % to 40 %, and lower costs of electricity, \$0.045 to \$0.055/kWh, compared to conventional direct-combustion systems. The efficiency of power production can be even higher (about 55 %) when the fuel gas is converted to hydrogen followed by electrochemical conversion to electricity in a fuel cell. The Energy Policy Act of 1992 includes a number of provisions to promote the commercialisation of biomass power production. The recent Global Climate Change Action Plan also includes several programs and incentives for biomass power production. A summary of U.S. demonstration

3. Biomass Waste Gasification – Can Be the Two Stage Process Suitable for Tar Reduction and Power Generation?

Czech Academy of Sciences Publication Activity Database

Šulc, J.; Štojdl, J.; Richter, M.; Popelka, J.; Svoboda, Karel; Smetana, J.; Vacek, J.; Skoblia, S.; Buryan, P.

2012-01-01

Roč. 32, č. 4 (2012), s. 692-700 ISSN 0956-053X Grant - others:RFCR(XE) CT-2010-00009 Institutional research plan: CEZ:AV0Z40720504 Keywords : waste biomass * gasification * tar Subject RIV: JE - Non-nuclear Energetics, Energy Consumption ; Use Impact factor: 2.485, year: 2012

4. Pyrolysis/gasification of biomass for synthetic fuel production using a hybrid gas- water stabilized plasma torch

Czech Academy of Sciences Publication Activity Database

Van Oost, G.; Hrabovský, Milan; Kopecký, Vladimír; Konrád, Miloš; Hlína, Michal; Kavka, Tetyana

2008-01-01

Roč. 83, č. 1 (2008), s. 209-212 ISSN 0042-207X R&D Projects: GA ČR GA202/08/1084 Institutional research plan: CEZ:AV0Z20430508 Keywords : Thermal plasma * pyrolysis * biomass gasification Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.114, year: 2008

5. Pyrolysis/gasification of biomass for synthetic fuel production using a hybrid gas- water stabilized plasma torch

Czech Academy of Sciences Publication Activity Database

Van Oost, G.; Hrabovský, Milan; Kopecký, Vladimír; Konrád, Miloš; Hlína, Michal; Kavka, Tetyana; Beeckman, E.; Verstraeten, J.

2007-01-01

Roč. 6, č. 1 (2007), s. 9-12. ISBN 978-4-9900642-5-9 R&D Projects: GA ČR GA202/05/0669 Institutional research plan: CEZ:AV0Z20430508 Keywords : Thermal plasma * pyrolysis * biomass gasification Subject RIV: BL - Plasma and Gas Discharge Physics

6. On the gasification of wet biomass in supercritical water : over de vergassing van natte biomassa in superkritiek water

NARCIS (Netherlands)

Withag, J.A.M.

2013-01-01

Supercritical water gasification (SCWG) is a challenging thermo-chemical conversion route for wet biomass and waste streams into hydrogen and/or methane. At temperatures and pressures above the critical point the physical properties of water differ strongly from liquid water or steam. Because of the

7. Carbon exergy tax applied to biomass integrated gasification combined cycle in sugarcane industry

International Nuclear Information System (INIS)

Fonseca Filho, Valdi Freire da; Matelli, José Alexandre; Perrella Balestieri, José Antonio

2016-01-01

The development of technologies based on energy renewable sources is increasing worldwide in order to diversify the energy mix and satisfy the rigorous environmental legislation and international agreements to reduce pollutant emission. Considering specific characteristics of biofuels available in Brazil, studies regarding such technologies should be carried out aiming energy mix diversification. Several technologies for power generation from biomass have been presented in the technical literature, and plants with BIGCC (biomass integrated gasification combined cycle) emerge as a major technological innovation. By obtaining a fuel rich in hydrogen from solid biomass gasification, BIGCC presents higher overall process efficiency than direct burning of the solid fuel in conventional boilers. The objective of this paper is to develop a thermodynamic and chemical equilibrium model of a BIGCC configuration for sugarcane bagasse. The model embodies exergetic cost and CO 2 emission analyses through the method of CET (carbon exergy tax). An exergetic penalty comparison between the BIGCC technology (with and without CO 2 capture and sequestration), a natural gas combined cycle and the traditional steam cycle of sugarcane sector is then presented. It is verified that the BIGCC configuration with CO 2 capture and sequestration presents technical and environmental advantages when compared to traditional technology. - Highlights: • We compared thermal cycles with the exergetic carbon exergy tax. • Thermal cycles with and without carbon capture and sequestration were considered. • Burned and gasified sugarcane bagasse was assumed as renewable fuel. • Exergetic carbon penalty tax was imposed to all studied configurations. • BIGCC with carbon sequestration revealed to be advantageous.

8. Assessment of the Potential of Biomass Gasification for Electricity Generation in Bangladesh

Directory of Open Access Journals (Sweden)

Barun Kumar Das

2014-01-01

Full Text Available Bangladesh is an agriculture based country where more than 65 percent of the people live in rural areas and over 70% of total primary energy consumption is covered by biomass, mainly agricultural waste and wood. Only about 6% of the entire population has access to natural gas, primarily in urban areas. Electricity production in Bangladesh largely depends on fossil fuel whose reserve is now under threat and the government is now focusing on the alternating sources to harness electricity to meet the continuous increasing demand. To reduce the dependency on fossil fuels, biomass to electricity could play a vital role in this regard. This paper explores the biomass based power generation potential of Bangladesh through gasification technology—an efficient thermochemical process for distributed power generation. It has been estimated that the total power generation from the agricultural residue is about 1178 MWe. Among them, the generation potential from rice husk, and bagasses is 1010 MWe, and 50 MWe, respectively. On the other hand, wheat straw, jute stalks, maize residues, lentil straw, and coconut shell are also the promising biomass resources for power generation which counted around 118 MWe. The forest residue and municipal solid waste could also contribute to the total power generation 250 MWe and 100 MWe, respectively.

9. Analysis of biomass and waste gasification lean syngases combustion for power generation using spark ignition engines.

Science.gov (United States)

Marculescu, Cosmin; Cenuşă, Victor; Alexe, Florin

2016-01-01

The paper presents a study for food processing industry waste to energy conversion using gasification and internal combustion engine for power generation. The biomass we used consisted in bones and meat residues sampled directly from the industrial line, characterised by high water content, about 42% in mass, and potential health risks. Using the feedstock properties, experimentally determined, two air-gasification process configurations were assessed and numerically modelled to quantify the effects on produced syngas properties. The study also focused on drying stage integration within the conversion chain: either external or integrated into the gasifier. To comply with environmental regulations on feedstock to syngas conversion both solutions were developed in a closed system using a modified down-draft gasifier that integrates the pyrolysis, gasification and partial oxidation stages. Good quality syngas with up to 19.1% - CO; 17% - H2; and 1.6% - CH4 can be produced. The syngas lower heating value may vary from 4.0 MJ/Nm(3) to 6.7 MJ/Nm(3) depending on process configuration. The influence of syngas fuel properties on spark ignition engines performances was studied in comparison to the natural gas (methane) and digestion biogas. In order to keep H2 molar quota below the detonation value of ⩽4% for the engines using syngas, characterised by higher hydrogen fraction, the air excess ratio in the combustion process must be increased to [2.2-2.8]. The results in this paper represent valuable data required by the design of waste to energy conversion chains with intermediate gas fuel production. The data is suitable for Otto engines characterised by power output below 1 MW, designed for natural gas consumption and fuelled with low calorific value gas fuels. Copyright © 2015 Elsevier Ltd. All rights reserved.

10. Hot Gas Conditioning: Recent Progress with Larger-Scale Biomass Gasification Systems; Update and Summary of Recent Progress

Energy Technology Data Exchange (ETDEWEB)

Stevens, D. J.

2001-09-01

As a result of environmental and policy considerations, there is increasing interest in using renewable biomass resources as feedstock for power, fuels, and chemicals and hydrogen. Biomass gasification is seen as an important technology component for expanding the use of biomass. Advanced biomass gasification systems provide clean products that can be used as fuel or synthesis gases in a variety of environmentally friendly processes. Advanced end-use technologies such as gas turbines or synthesis gas systems require high quality gases with narrowly defined specifications. Other systems such as boilers may also have fuel quality requirements, but they will be substantially less demanding. The gas product from biomass gasifiers contains quantities of particulates, tars, and other constituents that may exceed these specified limits. As a result, gas cleaning and conditioning will be required in most systems. Over the past decade, significant research and development activities have been conducted on the topic of gas cleanup and conditioning. This report provides an update of efforts related to large-scale biomass gasification systems and summarizes recent progress. Remaining research and development issues are also summarized.

11. Utilisation of biomass gasification by-products for onsite energy production.

Science.gov (United States)

Vakalis, S; Sotiropoulos, A; Moustakas, K; Malamis, D; Baratieri, M

2016-06-01

Small scale biomass gasification is a sector with growth and increasing applications owing to the environmental goals of the European Union and the incentivised policies of most European countries. This study addresses two aspects, which are at the centre of attention concerning the operation and development of small scale gasifiers; reuse of waste and increase of energy efficiency. Several authors have denoted that the low electrical efficiency of these systems is the main barrier for further commercial development. In addition, gasification has several by-products that have no further use and are discarded as waste. In the framework of this manuscript, a secondary reactor is introduced and modelled. The main operating principle is the utilisation of char and flue gases for further energy production. These by-products are reformed into secondary producer gas by means of a secondary reactor. In addition, a set of heat exchangers capture the waste heat and optimise the process. This case study is modelled in a MATLAB-Cantera environment. The model is non-stoichiometric and applies the Gibbs minimisation principle. The simulations show that some of the thermal energy is depleted during the process owing to the preheating of flue gases. Nonetheless, the addition of a secondary reactor results in an increase of the electrical power production efficiency and the combined heat and power (CHP) efficiency. © The Author(s) 2016.

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

Directory of Open Access Journals (Sweden)

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.

13. Refining of new products and raw materials by gasification of biomass

Energy Technology Data Exchange (ETDEWEB)

Lassi, U.; Tynjaelae, P. (Univ. of Oulu, Dept. of Chemistry (Finland); Kokkola Univ. Consortium Chydenius (Finland)). email: ulla.lassi@oulu.fi; Granoe, U.-P. (Kokkola Univ. Consortium Chydenius (Finland)); Kuokkanen, T. (Univ. of Oulu, Dept. of Chemistry (Finland)); Muilu, Y. (Central Ostrobothnia Univ. of Applied Sciences/Centria, Ylivieska (Finland))

2009-07-01

Research project 'Refining of new products and raw materials by gasifying of biomass (High- Bio)' is carried out as a joint project between Kokkola University Consortium Chydenius (coordinator), University of Oulu, Department of Chemistry, Central Ostrobothnia University of Applied Sciences (Centria, Ylivieska), Luleaa University of Technology and ETC Piteaa. Project is financied by EU Interreg 4 A Pohjoinen programme in years 2008-2011. Information on the project is available at: http://www.chydenius.fi/yksikot/luonnontieteet/tutkimus/highbiointerreg-nord, where the info sheets can also be downloaded. Bioenergy and environment are the focus areas of HighBio research project. HighBio project consists of five work packages (WP), which are (1) development of the gasification process, (2) effect of raw materials on the gasification process, (3) utilisation of end-products, (4) evaluation and techno-economical analysis of process, and (5) delivery of information. The information produced and know-how developed will be integrated by the research groups

14. Product Chemistry and Process Efficiency of Biomass Torrefaction, Pyrolysis and Gasification Studied by High-Throughput Techniques and Multivariate Analysis

Science.gov (United States)

Xiao, Li

), fast growing energy crops (switchgrass), and popular forage crop (alfalfa), as well as biochar derived from those materials and their mixtures. It demonstrated that Py-MBMS coupled with MVA could be used as fast analytical tools for the study of not only biomass composition but also its thermal decomposition behaviors. It found that the impact of biomass composition heavily depends on the thermal decomposition temperature because at different temperature, the composition of biomass decomposed and the impact of minerals on the decomposition reaction varies. At low temperature (200-500°C), organic compounds attribute to the majority of variation in thermal decomposition products. At higher temperature, inorganics dramatically changed the pyrolysis pathway of carbohydrates and possibly lignin. In gasification, gasification tar formation is also observed to be impacted by ash content in vapor and char. In real reactor, biochar structure also has interactions with other fractions to make the final pyrolysis and gasification product. Based on the evaluation of process efficiencies during torrefaction, temperature ranging from 275°C to 300°C with short residence time (<10min) are proposed to be optimal torrefaction conditions. 500°C is preferred to 700°C as primary pyrolysis temperature in two stage gasification because higher primary pyrolysis temperature resulted in more tar and less gasification char. Also, in terms of carbon yield, more carbon is lost in tar while less carbon is retained in gas product using 700°C as primary pyrolysis temperature. In addition, pyrolysis char is found to produce less tar and more gas during steam gasification compared with gasification of pyrolysis vapor. Thus it is suggested that torrefaction might be an efficient pretreatment for biomass gasification because it can largely improve the yield of pyrolysis char during the primary pyrolysis step of gasification thus reduce the total tar of the overall gasification products. Future work

15. Experimental investigation of solid oxide fuel cells using biomass gasification producer gases

Energy Technology Data Exchange (ETDEWEB)

Norheim, Arnstein

2005-07-01

The main objective of this thesis is theoretical and experimental investigations related to utilisation of biomass gasification producer gases as fuel for Solid Oxide Fuel Cells (SOFC). Initial fundamental steps towards a future system of combined heat and power production based on biomass gasification and SOFC are performed and include: 1) Theoretical modeling of the composition of biomass gasification producer gases. 2) Experimental investigation of SOFC performance using biomass gasification producer gas as fuel. 3) Experimental investigation of SOFC performance using biomass gasification producer gas containing high sulphur concentration. The modeling of the composition of gasifier producer gas was performed using the program FactSage. The main objective was to investigate the amount and speciation of trace species in the producer gases as several parameters were varied. Thus, the composition at thermodynamic equilibrium of sulphur, chlorine, potassium, sodium and compounds of these were established. This was done for varying content of the trace species in the biomass material at different temperatures and fuel utilisation i.e. varying oxygen content in the producer gas. The temperature interval investigated was in the range of normal SOFC operation. It was found that sulphur is expected to be found as H2S irrespective of temperature and amount of sulphur. Only at very high fuel utilisation some S02 is formed. Important potassium containing compounds in the gas are gaseous KOH and K. When chlorine is present, the amount of KOH and K will decrease due to the formation of KCI. The level of sodium investigated here was low, but some Na, NaOH and NaCl is expected to be formed. Below a certain temperature, condensation of alkali rich carbonates may occur. The temperature at which condensation begins is mainly depending on the amount of potassium present; the condensation temperature increases with increasing potassium content. In the first experimental work

16. Design and System Analysis of Quad-Generation Plant Based on Biomass Gasification Integrated with District Heating

DEFF Research Database (Denmark)

Rudra, Souman

) technical impact to select different technologies and types of equipment from available options; and c) economic concern to validate new technology with existing one. To achieve the above issues a life cycle assessment (LCA) analysis and techno-economic analysis of quad-generation system have also included...... in this study. The overall aim of this work is to provide a complete assessment of the technical potential of biomass gasification for local heat and power supply in Denmark and replace of natural gas for the production. This study also finds and defines the future areas of research in the gasification...

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

Science.gov (United States)

Mastellone, Maria Laura; Zaccariello, Lucio; Santoro, Donato; Arena, Umberto

2012-04-01

The effect of oxygen-enriched air during fluidized bed co-gasification of a mixture of coal, plastics and wood has been investigated. The main components of the obtained syngas were measured by means of on-line analyzers and a gas chromatograph while those of the condensate phase were off-line analysed by means of a gas chromatography-mass spectrometer (GC-MS). The characterization of condensate phase as well as that of the water used as scrubbing medium completed the performed diagnostics. The experimental results were further elaborated in order to provide material and substances flow analyses inside the plant boundaries. These analyses allowed to obtain the main substance distribution between solid, gaseous and condensate phases and to estimate the conversion efficiency of carbon and hydrogen but also to easily visualise the waste streams produced by the process. The process performance was then evaluated on the basis of parameters related to the conversion efficiency of fuels into valuable products (i.e. by considering tar and particulate as process losses) as well as those related to the energy recovery. Copyright Â© 2011 Elsevier Ltd. All rights reserved.

18. Numerical Simulation of Fluidized Bed Gasifier for Integrated Gasification Combined Cycle

Directory of Open Access Journals (Sweden)

CHEN Ju-hui

2017-06-01

Full Text Available The overall thermal efficiency of the integrated gasification combined cycle ( IGCC has not been sufficiently improved. In order to achieve higher power generation efficiency，the advanced technology of IGCC has been developed which is on the basis of the concept of exergy recovery. IGCC systems and devices from the overall structure of opinion，this technology will generate electricity for the integration of advanced technology together，the current utilization of power generation technology and by endothermic reaction of steam in the gasifier，a gas turbine exhaust heat recovery or the solid oxide fuel cell. It is estimated that such the use of exergy recycling has the advantage of being easy to use，separating，collecting fixed CO2，making it very attractive，and can increase the overall efficiency by 10% or more. The characteristics of fluidized bed gasifier，one of the core equipment of the IGCC system，and its effect on the whole system were studied.

19. Production of high quality syngas from argon/water plasma gasification of biomass and waste.

Science.gov (United States)

Hlina, M; Hrabovsky, M; Kavka, T; Konrad, M

2014-01-01

Extremely hot thermal plasma was used for the gasification of biomass (spruce sawdust, wood pellets) and waste (waste plastics, pyrolysis oil). The plasma was produced by a plasma torch with DC electric arc using unique hybrid stabilization. The torch input power of 100-110 kW and the mass flow rate of the gasified materials of tens kg/h was set up during experiments. Produced synthetic gas featured very high content of hydrogen and carbon monoxide (together approximately 90%) that is in a good agreement with theory. High quality of the produced gas is given by extreme parameters of used plasma--composition, very high temperature and low mass flow rate. Copyright © 2013 Elsevier Ltd. All rights reserved.

20. Gasification kinetic analysis of the three pseudocomponents of biomass-cellulose, semicellulose and lignin.

Science.gov (United States)

Chen, Tianju; Wu, Jingli; Zhang, Jinzhi; Wu, Jinhu; Sun, Li

2014-02-01

The gasification kinetic analysis of the three pseudocomponents (hemicellulose, cellulose and lignin) of biomass decomposition in the agent of CO2 were investigated. The Multi-peaks method was used to fit the Gaussian distribution model of DTG curves. The Friedman method was used to estimate the effective Eα, and the master plot method was used for the determination of the kinetic model. The results showed that there were two reaction stages for semi-cellulose and lignin. The DTG curves of semicellulose and lignin cannot be fitted by Gaussian distribution model. The Eα were ranged from 80 to 220kJmol(-1) for the three pseudocomponents. The Fn model could describe the kinetic process of stage I of semi-cellulose decomposition. Both cellulose and stage II of semicellulose decomposition could be described by An model and the two reaction stages of the lignin were fitted the Rn model very well. Copyright © 2013 Elsevier Ltd. All rights reserved.

1. Technoeconomic analysis of a methanol plant based on gasification of biomass and electrolysis of water

DEFF Research Database (Denmark)

Clausen, Lasse Røngaard; Houbak, N.; Elmegaard, Brian

2010-01-01

Methanol production process configurations based on renewable energy sources have been designed. The processes were analyzed in the thermodynamic process simulation tool DNA. The syngas used for the catalytic methanol production was produced by gasification of biomass, electrolysis of water, CO2...... from post-combustion capture and autothermal reforming of natural gas or biogas. Underground gas storage of hydrogen and oxygen was used in connection with the electrolysis to enable the electrolyser to follow the variations in the power produced by renewables. Six plant configurations, each...... with a different syngas production method, were compared. The plants achieve methanol exergy efficiencies of 59-72%, the best from a configuration incorporating autothermal reforming of biogas and electrolysis of water for syngas production. The different processes in the plants are highly heat integrated...

2. Supercritical water gasification of biomass for H2 production: process design.

Science.gov (United States)

Fiori, Luca; Valbusa, Michele; Castello, Daniele

2012-10-01

The supercritical water gasification (SCWG) of biomass for H(2) production is analyzed in terms of process development and energetic self-sustainability. The conceptual design of a plant is proposed and the SCWG process involving several substrates (glycerol, microalgae, sewage sludge, grape marc, phenol) is simulated by means of AspenPlus™. The influence of various parameters - biomass concentration and typology, reaction pressure and temperature - is analyzed. The process accounts for the possibility of exploiting the mechanical energy of compressed syngas (later burned to sustain the SCWG reaction) through expansion in turbines, while purified H(2) is fed to fuel cells. Results show that the SCWG reaction can be energetically self-sustained if minimum feed biomass concentrations of 15-25% are adopted. Interestingly, the H(2) yields are found to be maximal at similar feed concentrations. Finally, an energy balance is performed showing that the whole process could provide a net power of about 150 kW(e)/(1000 kg(feed)/h). Copyright © 2012 Elsevier Ltd. All rights reserved.

3. 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)

4. Molecular level insights to the interaction of toluene with ZrO2-based biomass gasification gas clean-up catalysts

NARCIS (Netherlands)

Viinikainen, T.; Kauppi, I.; Korhonen, S.; Lefferts, Leonardus; Kanervo, J.; Lehtonen, J.

2013-01-01

Gasification of biomass, followed by ZrO2-catalyzed hot gas clean-up at 600–900 °C for the oxidation of impurities (such as tar), is an environmentally attractive way to produce heat and power or synthesis gas. The interaction of toluene (as a model compound for tar) with ZrO2-based gasification gas

5. Integrated biomass gasification using the waste heat from hot slags: Control of syngas and polluting gas releases

International Nuclear Information System (INIS)

Sun, Yongqi; Seetharaman, Seshadri; Liu, Qianyi; Zhang, Zuotai; Liu, Lili; Wang, Xidong

2016-01-01

In this study, the thermodynamics of a novel strategy, i.e., biomass/CO 2 gasification integrated with heat recovery from hot slags in the steel industry, were systemically investigated. Both the target syngas yield and the polluting gas release were considered where the effect of gasifying conditions including temperature, pressure and CO 2 reacted was analyzed and then the roles of hot slags were further clarified. The results indicated that there existed an optimum temperature for the maximization of H 2 production. Compared to blast furnace slags, steel slags remarkably increased the CO yield at 600–1400 °C due to the existence of iron oxides and decreased the S-containing gas releases at 400–700 °C, indicating potential desulfurizing ability. The identification of biomass/CO 2 gasification thermodynamics in presence of slags could thus provide important clues not only for the deep understanding of biomass gasification but also for the industrial application of this emerging strategy from the viewpoint of syngas optimization and pollution control. - Highlights: • Biomass/CO 2 gasification was integrated with the heat recovery from hot slags. • Both syngas yield and polluting gas release during gasification were determined. • There existed an optimum temperature for the maximization of H 2 production. • Steel slags increased CO yield at 600–1400 °C due to the existence of iron oxides. • Steel slags remarkably decreased the releases of S-containing gas at 400–700 °C.

6. 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.

7. Modelling of dynamics of combustion of biomass in fluidized beds

Directory of Open Access Journals (Sweden)

Saastamoinen Jaakko J.

2004-01-01

Full Text Available New process concepts in energy production and biofuel, which are much more reactive than coal, call for better controllability of the combustion in circulating fluidized bed boilers. Simplified analysis describing the dynamics of combustion in fluidized bed and circulating fluidized bed boilers is presented. Simple formulas for the estimation of the responses of the burning rate and fuel inventory to changes in fuel feeding are presented. Different changes in the fuel feed, such as an impulse, step change, linear increase and cyclic variation are considered. The dynamics of the burning with a change in the feed rate depends on the fuel reactivity and particle size. The response of a fuel mixture with a wide particle size distribution can be found by summing up the effect of different fuel components and size fractions. Methods to extract reaction parameters form dynamic tests in laboratory scale reactors are discussed. The residence time of fuel particles in the bed and the resulting char inventory in the bed decrease with increasing fuel reactivity and differences between coal and biomass is studied. The char inventory affects the stability of combustion. The effect of char inventory and oscillations in the fuel feed on the oscillation of the flue gas oxygen concentration is studied by model calculation. A trend found by earlier measurements is explained by the model.

8. Advanced development of a pressurized ash agglomerating fluidized-bed coal gasification system: Topical report, Process analysis, FY 1983

Energy Technology Data Exchange (ETDEWEB)

None

1987-07-31

KRW Energy Systems, Inc., is engaged in the continuing development of a pressurized, fluidized-bed gasification process at its Waltz Mill Site in Madison, Pennsylvania. The overall objective of the program is to demonstrate the viability of the KRW process for the environmentally-acceptable production of low- and medium-Btu fuel gas from a variety of fossilized carbonaceous feedstocks and industrial fuels. This report presents process analysis of the 24 ton-per-day Process Development Unit (PDU) operations and is a continuation of the process analysis work performed in 1980 and 1981. Included is work performed on PDU process data; gasification; char-ash separation; ash agglomeration; fines carryover, recycle, and consumption; deposit formation; materials; and environmental, health, and safety issues. 63 figs., 43 tabs.

9. Multi-gene genetic programming based predictive models for municipal solid waste gasification in a fluidized bed gasifier.

Science.gov (United States)

Pandey, Daya Shankar; Pan, Indranil; Das, Saptarshi; Leahy, James J; Kwapinski, Witold

2015-03-01

A multi-gene genetic programming technique is proposed as a new method to predict syngas yield production and the lower heating value for municipal solid waste gasification in a fluidized bed gasifier. The study shows that the predicted outputs of the municipal solid waste gasification process are in good agreement with the experimental dataset and also generalise well to validation (untrained) data. Published experimental datasets are used for model training and validation purposes. The results show the effectiveness of the genetic programming technique for solving complex nonlinear regression problems. The multi-gene genetic programming are also compared with a single-gene genetic programming model to show the relative merits and demerits of the technique. This study demonstrates that the genetic programming based data-driven modelling strategy can be a good candidate for developing models for other types of fuels as well. Copyright © 2014 Elsevier Ltd. All rights reserved.

10. 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...

11. Modelling of gasification using deferent kinds of biomass in a downdraft reactor

International Nuclear Information System (INIS)

Rabell Ferran, Santiago J.; Brito Sauvanell, Angel L

2011-01-01

In this work is exposed the methodology of realization of a equilibrium model, capable to predict the composition of the generated gas, its caloric value, the cold and hot efficiency and the quantity of air per quantity of biomass in a downdraft reactor. For this model's realization it was considered that all the chemical reactions that happen in the gasification area are in thermodynamic equilibrium, doesn't considered tar formation, and alone it is considered the methane formation(CH4), it is not considered formation of CxHy. To make more practical and more accessible the model was carried out a software in Excel. The work use as fuel, wood, paddy husk, paper and solid waste. The behavior of generated gases was studied with the variation of the content of humidity. Were determined the calorific value of generated gas, and the value of the cold and hot efficiency for each biomass varying the content of humidity of the same one, where it shows for 20% of humidity, for the wood a value of 5,65MJ/Nm3, for the paddy husk is of 3,88 MJ/Nm3, for the paper it is of 5,83 MJ/Nm3, and for the waste it is of 4,36 MJ/Nm3; and the cold and hot efficiency for wood 30,16%, and 60,37%; for paddy husk 25,43% and 40,83%, paper 33,40% and 63,28%; and waste 22,18% and 41,35% respectively. It was also determined the gravimetric relationship of necessary air/ biomass for each biomass. (author)

12. 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. Copyright © 2012 Elsevier B.V. All rights reserved.

13. Thermoeconomic analysis of Biomass Integrated Gasification Gas Turbine Combined Cycle (BIG GT CC) cogeneration plant

Energy Technology Data Exchange (ETDEWEB)

Arrieta, Felipe Raul Ponce; Lora, Electo Silva [Escola Federal de Engenharia de Itajuba, MG (Brazil). Nucleo de Estudos de Sistemas Termicos]. E-mails: aponce@iem.efei.br; electo@iem.efei.br; Perez, Silvia Azucena Nebra de [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Mecanica. Dept. de Energia]. E-mail: sanebra@fem. unicamp.br

2000-07-01

Using thermoeconomics as a tool to identify the location and magnitude of the real thermodynamic losses (energy waste, or exergy destruction and exergy losses) it is possible to assess the production costs of each product (electric power and heat) and the exergetic and exergoeconomic cost of each flow in a cogeneration plant to assist in decision-marketing procedures concerning to plant design, investment, operation and allocations of research funds. Thermo economic analysis of Biomass Integrated Gasification Gas Turbine Combined Cycle (BIG GT CC) cogeneration plant for its applications in sugar cane mills brings the following results: the global exergetic efficiency is low; the highest irreversibilities occur in the following equipment, by order: scrubber (38%), gas turbine (16%), dryer (12%), gasifier and HRSG (6%); due to the adopted cost distribution methodology, the unit exergetic cost of the heat (4,11) is lower than electricity (4,71); the lower market price of biomass is one of the most sensible parameter in the possible implementation of BIG-GT technology in sugar cane industry; the production costs are 31 US\$/MWh and 32 US\$/MWh for electricity and heat, respectively. The electricity cost is, after all, competitive with the actual market price. The electricity and heat costs are lower or almost equal than other values reported for actual Rankine cycle cogeneration plants. (author)

14. An integrated approach to energy recovery from biomass and waste: Anaerobic digestion-gasification-water treatment.

Science.gov (United States)

Milani, M; Montorsi, L; Stefani, M

2014-07-01

The article investigates the performance of an integrated system for the energy recovery from biomass and waste based on anaerobic digestion, gasification and water treatment. In the proposed system, the organic fraction of waste of the digestible biomass is fed into an anaerobic digester, while a part of the combustible fraction of the municipal solid waste is gasified. Thus, the obtained biogas and syngas are used as a fuel for running a cogeneration system based on an internal combustion engine to produce electric and thermal power. The waste water produced by the integrated plant is recovered by means of both forward and inverse osmosis. The different processes, as well as the main components of the system, are modelled by means of a lumped and distributed parameter approach and the main outputs of the integrated plant such as the electric and thermal power and the amount of purified water are calculated. Finally, the implementation of the proposed system is evaluated for urban areas with a different number of inhabitants and the relating performance is estimated in terms of the main outputs of the system. © The Author(s) 2014.

15. Supercritical Water Gasification of Biomass in a Ceramic Reactor: Long-Time Batch Experiments

Directory of Open Access Journals (Sweden)

Daniele Castello

2017-10-01

Full Text Available Supercritical water gasification (SCWG is an emerging technology for the valorization of (wet biomass into a valuable fuel gas composed of hydrogen and/or methane. The harsh temperature and pressure conditions involved in SCWG (T > 375 °C, p > 22 MPa are definitely a challenge for the manufacturing of the reactors. Metal surfaces are indeed subject to corrosion under hydrothermal conditions, and expensive special alloys are needed to overcome such drawbacks. A ceramic reactor could be a potential solution to this issue. Finding a suitable material is, however, complex because the catalytic effect of the material can influence the gas yield and composition. In this work, a research reactor featuring an internal alumina inlay was utilized to conduct long-time (16 h batch tests with real biomasses and model compounds. The same experiments were also conducted in batch reactors made of stainless steel and Inconel 625. The results show that the three devices have similar performance patterns in terms of gas production, although in the ceramic reactor higher yields of C2+ hydrocarbons were obtained. The SEM observation of the reacted alumina surface revealed a good resistance of such material to supercritical conditions, even though some intergranular corrosion was observed.

16. The fate of heavy metals during combustion and gasification of contaminated biomass-a brief review.

Science.gov (United States)

Nzihou, Ange; Stanmore, Brian

2013-07-15

The literature on the presence of heavy metals in contaminated wastes is reviewed. Various categories of materials produced from domestic and industrial activities are included, but municipal solid waste, which is a more complex material, is excluded. This review considers among the most abundant the following materials - wood waste including demolition wood, phytoremediation scavengers and chromated copper arsenate (CCA) timber, sludges including de-inking sludge and sewage sludge, chicken litter and spent pot liner. The partitioning of the metals in the ashes after combustion or gasification follows conventional behaviour, with most metals retained, and higher concentrations in the finer sizes due to vaporisation and recondensation. The alkali metals have been shown to catalyse the biomass conversion, particularly lithium and potassium, although other metals are active to a lesser extent. The most prevalent in biomass is potassium, which is not only inherently active, but volatilises to become finely distributed throughout the char mass. Because the metals are predominantly found in the ash, the effectiveness of their removal depends on the efficiency of the collection of particulates. The potential for disposal into soil depends on the initial concentration in the feed material. Copyright © 2013 Elsevier B.V. All rights reserved.

17. Analysis and comparison of biomass pyrolysis/gasification condensates: an interim report

Energy Technology Data Exchange (ETDEWEB)

Elliott, D.C.

1985-09-01

This report provides results of chemical and physical analysis of condensates from eleven biomass gasification and pyrolysis systems. The analyses were performed in order to provide more detailed data concerning these condensates for the different process research groups and to allow a determination of the differences in properties of the condensates as a function of reactor environment. The samples were representative of the various reactor configurations being researched within the Department of Energy, Biomass Thermochemical Conversion program. The condensates included tar phases, aqueous phases and, in some cases, both phases depending on the output of the particular reactor system. The analyses included gross compositional analysis (elemental analysis, ash, moisture), physical characterization (pour point, viscosity, density, heat of combustion, distillation), specific chemical analysis (gas chromatography/mass spectrometry, infrared spectrophotometry, proton and carbon-13 nuclear magnetic resonance spectrometry) and biological activity (Ames assay). The analytical data demonstrate the wide range of chemical composition of the organics recovered in the condensates and suggests a direct relationship between operating temperature and chemical composition of the condensates. A continuous pathway of thermal degradation of the tar components as a function of temperature is proposed. Variations in the chemical composition of the organic components in the tars are reflected in the physical properties of tars and phase stability in relation to water in the condensate. The biological activity appears to be limited to the tars produced at high temperatures as a result of formation of polycyclic aromatic hydrocarbons in high concentrations. 55 refs., 13 figs., 6 tabs.

18. Comparative life cycle assessment (LCA) of construction and demolition (C&D) derived biomass and U.S. northeast forest residuals gasification for electricity production.

Science.gov (United States)

Nuss, Philip; Gardner, Kevin H; Jambeck, Jenna R

2013-04-02

With the goal to move society toward less reliance on fossil fuels and the mitigation of climate change, there is increasing interest and investment in the bioenergy sector. However, current bioenergy growth patterns may, in the long term, only be met through an expansion of global arable land at the expense of natural ecosystems and in competition with the food sector. Increasing thermal energy recovery from solid waste reduces dependence on fossil- and biobased energy production while enhancing landfill diversion. Using inventory data from pilot processes, this work assesses the cradle-to-gate environmental burdens of plasma gasification as a route capable of transforming construction and demolition (C&D) derived biomass (CDDB) and forest residues into electricity. Results indicate that the environmental burdens associated with CDDB and forest residue gasification may be similar to conventional electricity generation. Land occupation is lowest when CDDB is used. Environmental impacts are to a large extent due to coal cogasified, coke used as gasifier bed material, and fuel oil cocombusted in the steam boiler. However, uncertainties associated with preliminary system designs may be large, particularly the heat loss associated with pilot scale data resulting in overall low efficiencies of energy conversion to electricity; a sensitivity analysis assesses these uncertainties in further detail.

19. Effects of blend ratio between high density polyethylene and biomass on co-gasification behavior in a two-stage gasification system

KAUST Repository

Park, Jae Hyun

2016-08-12

The co-gasification of a high density polyethylene (HDPE) blended with a biomass has been carried out in a two-stage gasification system which comprises an oxidative pyrolysis reactor and a thermal plasma reactor. The equivalence ratio was changed from 0.38 to 0.85 according to the variation of blend ratio between HDPE and biomass. The highest production yield was achieved to be 71.4 mol/h, when the equivalence ratio was 0.47. A large amount of hydrocarbons was produced from the oxidative pyrolysis reactor as decreasing equivalence ratio below 0.41, while the CO2 concentration significantly increased with a high equivalence ratio over 0.65. The production yield was improved by the thermal plasma reactor due to the conversion of hydrocarbons into syngas in a high temperature region of thermal plasma. At the equivalence ratio of 0.47, conversion selectivities of CO and H2 from hydrocarbons were calculated to be 74% and 44%, respectively. © 2016 Hydrogen Energy Publications LLC.

20. Energy efficient thermochemical conversion of very wet biomass to biofuels by integration of steam drying, steam electrolysis and gasification

DEFF Research Database (Denmark)

Clausen, Lasse Røngaard

2017-01-01

A novel system concept is presented for the thermochemical conversion of very wet biomasses such as sewage sludge and manure. The system integrates steam drying, solid oxide electrolysis cells (SOEC) and gasification for the production of synthetic natural gas (SNG). The system is analyzed...... by thermodynamic modelling and the analysis shows that the system can handle mechanically dried biomasses with a water content of 70 wt% and an ash content of up to 50 wt% (dry basis). A high tolerable ash content is an advantage because very wet biomasses, such as sewage sludge and manure, have a high ash content....... The analysis shows that the total efficiency of the novel system is 69–70% depending on the biomass ash content, while the biomass to SNG energy ratio is 165%, which is near the theoretical maximum because electrolytic hydrogen is supplied to the synthesis gas. It is proposed to combine the novel system...

1. Simulated performance of biomass gasification based combined power and refrigeration plant for community scale application

Science.gov (United States)

Chattopadhyay, S.; Mondal, P.; Ghosh, S.

2016-07-01

Thermal performance analysis and sizing of a biomass gasification based combined power and refrigeration plant (CPR) is reported in this study. The plant is capable of producing 100 kWe of electrical output while simultaneously producing a refrigeration effect, varying from 28-68 ton of refrigeration (TR). The topping gas turbine cycle is an indirectly heated all-air cycle. A combustor heat exchanger duplex (CHX) unit burns producer gas and transfer heat to air. This arrangement avoids complex gas cleaning requirements for the biomass-derived producer gas. The exhaust air of the topping GT is utilized to run a bottoming ammonia absorption refrigeration (AAR) cycle via a heat recovery steam generator (HRSG), steam produced in the HRSG supplying heat to the generator of the refrigeration cycle. Effects of major operating parameters like topping cycle pressure ratio (rp) and turbine inlet temperature (TIT) on the energetic performance of the plant are studied. Energetic performance of the plant is evaluated via energy efficiency, required biomass consumption and fuel energy savings ratio (FESR). The FESR calculation method is significant for indicating the savings in fuel of a combined power and process heat plant instead of separate plants for power and process heat. The study reveals that, topping cycle attains maximum power efficiency of 30%in pressure ratio range of 8-10. Up to a certain value of pressure ratio the required air flow rate through the GT unit decreases with increase in pressure ratio and then increases with further increase in pressure ratio. The capacity of refrigeration of the AAR unit initially decreases up to a certain value of topping GT cycle pressure ratio and then increases with further increase in pressure ratio. The FESR is found to be maximized at a pressure ratio of 9 (when TIT=1100°C), the maximum value being 53%. The FESR is higher for higher TIT. The heat exchanger sizing is also influenced by the topping cycle pressure ratio and GT-TIT.

2. Effect of Air Staging Ratios on the Burning Rate and Emissions in an Underfeed Fixed-Bed Biomass Combustor

Directory of Open Access Journals (Sweden)

Araceli Regueiro

2016-11-01

Full Text Available This experimental work studies a small-scale biomass combustor (5–12 kW with an underfed fixed bed using low air staging ratios (15%–30%. This document focuses on the influence of the operative parameters on the combustion process, so gaseous emissions and the distribution and concentration of particulate matter have also been recorded. The facility shows good stability and test repeatability. For the studied airflow ranges, the results show that increasing the total airflow rate does not increase the overall air excess ratio because the burning rate is proportionally enhanced (with some slight differences that depend on the air staging ratio. Consequently, the heterogeneous reactions at the bed remain in the so-called oxygen-limited region, and thus the entire bed operates under sub-stoichiometric conditions with regards of the char content of the biomass. In addition, tests using only primary air (no staging may increase the fuel consumption, but in a highly incomplete way, approaching a gasification regime. Some measured burning rates are almost 40% higher than previous results obtained in batch combustors due to the fixed position of the ignition front. The recorded concentration of particulate matter varies between 15 and 75 mg/Nm3, with a main characteristic diameter between 50 and 100 nm.

3. Monitoring `Renewable fuels`. Gasification and pyrolysis of biomass. Second situation report; Monitoring ``Nachwachsende Rohstoffe``. Vergasung und Pyrolyse von Biomasse. Zweiter Sachstandsbericht

Energy Technology Data Exchange (ETDEWEB)

Roesch, C.; Wintzer, D.

1997-04-01

The second situation report deals with gasification and pyrolysis as means of improving the energetic utilisation of wood and strawlike biomass and with various possibilities of utilising the gas produced in these processes. It also presents different gasification techniques, measures for gas purification, and ways of utilising gas for electricity generation. Out of the wide range of possible process combinations for producing energy from biomass the report only deals more closely with a few concepts that appear very promising from today`s viewpoint. Working from the current state and perspectives of technical development and from prospective operating conditions and potential market chances of pyrolysis and gasification the report deliberates on the future orientation of research, development, and demonstration activities. (orig./SR) [Deutsch] Im zweiten Sachstandsbericht werden die Vergasung und Pyrolyse zur besseren energetischen Nutzung von Holz und halmartiger Biomasse und verschiedene Moeglichkeiten zur Verwertung des dabei erzeugten Gases betrachtet. Es werden unterschiedliche Vergasungstechniken, Massnahmen zur Gasreinigung und Arten der Gasnutzung zur Stromgewinnung dargestellt. Aus der Vielzahl an moeglichen Kombinationen werden einige, aus gegenwaertiger Sichtweise besonders vielversprechende Konzepte zur Energieerzeugung ueber die Biomassevergasung naeher ausgefuehrt. Ausgehend vom Stand und von den Perspektiven der technischen Entwicklungen sowie den Einsatzbedingungen und potentiellen Marktchancen werden Schlussfolgerungen fuer die zukuenftige Ausrichtung im Bereich Forschung, Entwicklung und Demonstration Anstrengungen gezogen. (orig./SR)

4. Design and System Analysis of Quad-Generation Plant Based on Biomass Gasification Integrated with District Heating

DEFF Research Database (Denmark)

Rudra, Souman

This thesis presents the development of energy system for simulation, techno-economic optimization and design of a quad-generation energy system based on biomass gasification. An efficient way of reducing CO2 emission from the environment is by increasing the use of biomass in the energy sector...... alternative by upgrading existing district heating plant. It provides a generic modeling framework to design flexible energy system in near future. These frameworks address the three main issues arising in the planning and designing of energy system: a) socio impact at both planning and proses design level; b...

5. 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

To investigate options for increasing the electrical efficiency of decentralized combined heat and power (CHP) plants fuelled with biomass compared to conventional technology, this research explored the performance of an alternative plant design based on thermal biomass gasification and solid oxide......, carbon conversion factor in the gasifier and the efficiency of the DC/AC inverter were the most influential parameters in the model. Thus, a detailed study of the practical values of these parameters was conducted to determine the performance of the plant with the lowest possible uncertainty. The SOFC...

6. Biomass to hydrogen-rich syngas via catalytic steam gasification of bio-oil/biochar slurry.

Science.gov (United States)

Chen, Guanyi; Yao, Jingang; Liu, Jing; Yan, Beibei; Shan, Rui

2015-12-01

The catalytic steam gasification of bio-oil/biochar slurry (bioslurry) for hydrogen-rich syngas production was investigated in a fixed-bed reactor using LaXFeO3 (X=Ce, Mg, K) perovskite-type catalysts. The effects of elemental substitution in LaFeO3, temperature, water to carbon molar ratio (WCMR) and bioslurry weight hourly space velocity (WbHSV) were examined. The results showed that La0.8Ce0.2FeO3 gave the best performance among the prepared catalysts and had better catalytic activity and stability than the commercial 14 wt.% Ni/Al2O3. The deactivation caused by carbon deposition and sintering was significantly depressed in the case of La0.8Ce0.2FeO3 catalyst. Both higher temperature and lower WbHSV contributed to more H2 yield. The optimal WCMR was found to be 2, and excessive introducing of steam reduced hydrogen yield. The La0.8Ce0.2FeO3 catalyst gave a maximum H2 yield of 82.01% with carbon conversion of 65.57% under the optimum operating conditions (temperature=800°C, WCMR=2 and WbHSV=15.36h(-1)). Copyright © 2015 Elsevier Ltd. All rights reserved.

7. The role of char and tar in determining the gas-phase partitioning of nitrogen during biomass gasification

International Nuclear Information System (INIS)

Broer, Karl M.; Brown, Robert C.

2015-01-01

Highlights: • Switchgrass was gasified at an equivalence ratio of zero and 650–850 °C. • Short residence times were employed to minimize secondary reactions. • Char- and tar-bound nitrogen, NH 3 , HCN, and N 2 were all significant products. • Increasing temperature leads to increased release of gaseous nitrogen compounds. • Kinetic models of gasification should include nitrogen release from char and tar. - Abstract: Gasification is an attractive option for converting biomass into fuels and chemicals. Most biomass contains significant amounts of fuel-bound nitrogen (FBN), which partially converts into ammonia (NH 3 ) and hydrogen cyanide (HCN) during gasification. These nitrogen compounds are problematic as they can lead to NO X emissions or catalyst poisoning in downstream applications of syngas. FBN can convert to other products as well, including diatomic nitrogen (N 2 ), char-bound nitrogen (char-N), and tar-bound nitrogen (tar-N). Efforts to predict concentrations of NH 3 and HCN have been hindered by a lack of accurate, comprehensive measurements of nitrogen partitioning among gasification products. The present study gasified switchgrass under allothermal, short residence time conditions and measured NH 3 , HCN, char-N, and tar-N as a function of temperature in the range of 650–850 °C with diatomic nitrogen determined by difference. It was found that a major portion of FBN was retained in the char and tar products. As temperature was increased, char and tar were consumed, releasing nitrogen as gaseous NH 3 and HCN. This increase in undesirable nitrogen compounds is contrary to the predictions of most gasification models, which overlook the presence of significant nitrogen in char and tar even if they include tar cracking and char gasification reactions. The results of this study demonstrate that gas-phase reactions alone are not sufficient to predict the fate of nitrogen during gasification. In order for modeling efforts to obtain more accurate

8. Synergetic and inhibition effects in carbon dioxide gasification of blends of coals and biomass fuels of Indian origin.

Science.gov (United States)

Satyam Naidu, V; Aghalayam, P; Jayanti, S

2016-06-01

The present study investigates the enhancement of CO2 gasification reactivity of coals due to the presence of catalytic elements in biomass such as K2O, CaO, Na2O and MgO. Co-gasification of three Indian coal chars with two biomass chars has been studied using isothermal thermogravimetric analysis (TGA) in CO2 environment at 900, 1000 and 1100°C. The conversion profiles have been used to establish synergetic or inhibitory effect on coal char reactivity by the presence of catalytic elements in biomass char by comparing the 90% conversion time with and without biomass. It is concluded that both biomasses exhibit synergistic behavior when blended with the three coals with casuarina being more synergetic than empty fruit bunch. Some inhibitory effect has been noted for the high ash coal at the highest temperature with higher 90% conversion time for the blend over pure coal, presumably due to diffusional control of the conversion rate. Copyright © 2016 Elsevier Ltd. All rights reserved.

9. Characterization and activity of different dolomites for hot gas cleaning in biomass gasification

Energy Technology Data Exchange (ETDEWEB)

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

1997-12-31

The aim of this work is to identify if the type, origin or composition of the calcined dolomite has some influence on its activity for tar elimination in a hot flue gas coming from a biomass gasifier, bubbling fluidized bed type. For this purpose four different dolomites from four different quarries and companies have been studied. Chemical analysis, adsorption isotherms, surface and pore size distributions both with nitrogen and by mercury porosimetry etc.... have been made for three different samples of each dolomite. Activity tests for fresh tar destruction have been simultaneously carried out for each type of calcined dolomite in a fixed bed of 6 cm i.d. The tar elimination activity of the dolomite and the product distribution from it do not seem to depend much on the composition or type of the dolomite used. (author)

10. The direct observation of alkali vapor species in biomass combustion and gasification

Energy Technology Data Exchange (ETDEWEB)

French, R J; Dayton, D C; Milne, T A

1994-01-01

This report summarizes new data from screening various feedstocks for alkali vapor release under combustion conditions. The successful development of a laboratory flow reactor and molecular beam, mass spectrometer interface is detailed. Its application to several herbaceous and woody feedstocks, as well as a fast-pyrolysis oil, under 800 and 1,100{degrees}C batch combustion, is documented. Chlorine seems to play a large role in the facile mobilization of potassium. Included in the report is a discussion of relevant literature on the alkali problem in combustors and turbines. Highlighted are the phenomena identified in studies on coal and methods that have been applied to alkali speciation. The nature of binding of alkali in coal versus biomass is discussed, together with the implications for the ease of release. Herbaceous species and many agricultural residues appear to pose significant problems in release of alkali species to the vapor at typical combustor temperatures. These problems could be especially acute in direct combustion fired turbines, but may be ameliorated in integrated gasification combined cycles.

11. Analysis of ecotoxic influence of waste from the biomass gasification process.

Science.gov (United States)

Hawrot-Paw, Małgorzata; Koniuszy, Adam; Mikiciuk, Małgorzata; Izwikow, Monika; Stawicki, Tomasz; Sędłak, Paweł

2017-06-01

The purpose of this research was evaluation of the effect of soil contamination with waste coming from biomass gasification on chosen indicators of its biological activity, growth and development of spring barley, and change of physiological parameters of the plant. Chromatographic content and basic rheological parameters of the substances under research were also analyzed. Liquid wastes, tar, and mixture of tar and engine oil were introduced to the soil in the amount of 100 mg kg -1 DM soil. Based on the conducted research, it was ascertained that the changes in the number and activity of soil microorganisms were determined by the type of waste and its dose. Individual groups of microorganisms showed different sensitivity to the presence of pollution; however, the impact of tar and engine oil mixture was generally more disadvantageous. Presence of contaminants in the soil limited the growth of roots and aboveground parts of spring barley, especially when the dose was 10,000 mg kg -1 DM soil. The unfavorable impact of waste on photosynthesis efficiency on assimilation pigment synthesis and water content in the plant was recorded.

12. Thermodynamic Performance Study of Biomass Gasification, Solid Oxide Fuel Cell and Micro Gas Turbine Hybrid Systems

DEFF Research Database (Denmark)

Bang-Møller, Christian; Rokni, Masoud

2010-01-01

University of Denmark. The SOFC converts the syngas more efficiently than the MGT, which is reflected by the energetic electrical efficiency of the gasifier and MGT system in opposition to the gasifier and SOFC configuration – η_el = 28.1% versus η_el = 36.4%. By combining the SOFC and MGT, the unconverted......A system level modelling study of three combined heat and power systems based on biomass gasification is presented. Product gas is converted in a micro gas turbine (MGT) in the first system, in a solid oxide fuel cell (SOFC) in the second system and in a combined SOFC–MGT arrangement in the third...... system. An electrochemical model of the SOFC has been developed and calibrated against published data from Topsoe Fuel Cells A/S and the Risø National Laboratory. The modelled gasifier is based on an up scaled version (~500 kW_th) of the demonstrated low tar gasifier, Viking, situated at the Technical...

13. Treatment of biomass gasification wastewater using a combined wet air oxidation/activated sludge process

Energy Technology Data Exchange (ETDEWEB)

English, C.J.; Petty, S.E.; Sklarew, D.S.

1983-02-01

A lab-scale treatability study for using thermal and biological oxidation to treat a biomass gasification wastewater (BGW) having a chemical oxygen demand (COD) of 46,000 mg/l is described. Wet air oxidation (WA0) at 300/sup 0/C and 13.8 MPa (2000 psi) was used to initially treat the BGW and resulted in a COD reduction of 74%. This was followed by conventional activated sludge treatment using operating conditions typical of municipal sewage treatment plants. This resulted in an additional 95% COD removal. Overall COD reduction for the combined process was 99%. A detailed chemical analysis of the raw BGW and thermal and biological effluents was performed using gas chromatography/mass spectrometry (GC/MS). These results showed a 97% decrease in total extractable organics with WA0 and a 99.6% decrease for combined WA0 and activated sludge treatment. Components of the treated waters tended to be fewer in number and more highly oxidized. An experiment was conducted to determine the amount of COD reduction caused by volatilization during biological treatment. Unfortunately, this did not yield conclusive results. Treatment of BGW using WA0 followed by activated sludge appears to be very effective and investigations at a larger scale are recommended.

14. Storage capacity assessment of liquid fuels production by solar gasification in a packed bed reactor using a dynamic process model

International Nuclear Information System (INIS)

Kaniyal, Ashok A.; Eyk, Philip J. van; Nathan, Graham J.

2016-01-01

Highlights: • First analysis to assess storage requirements of a stand-alone packed bed, batch process solar gasifier. • 35 days of storage required for stand-alone solar system, whereas 8 h of storage required for hybrid system. • Sensitivity of storage requirement to reactor operation, solar region and solar multiple evaluated. - Abstract: The first multi-day performance analysis of the feasibility of integrating a packed bed, indirectly irradiated solar gasification reactor with a downstream FT liquids production facility is reported. Two fuel-loading scenarios were assessed. In one, the residual unconverted fuel at the end of a day is reused, while in the second, the residual fuel is discarded. To estimate a full year time-series of operation, a simplified statistical model was developed from short-period simulations of the 1-D heat transfer, devolatilisation and gasification chemistry model of a 150 kW th packed bed reactor (based on the authors’ earlier work). The short time-series cover a variety of solar conditions to represent seasonal, diurnal and cloud-induced solar transience. Also assessed was the influence of increasing the solar flux incident at the emitter plate of the packed bed reactor on syngas production. The combination of the annual time-series and daily model of syngas production was found to represent reasonably the seasonal transience in syngas production. It was then used to estimate the minimum syngas storage volume required to maintain a stable flow-rate and composition of syngas to a FT reactor over a full year of operation. This found that, for an assumed heliostat field collection area of 1000 m 2 , at least 64 days of storage is required, under both the Residual Fuel Re-Use and Discard scenarios. This figure was not sensitive to the two solar sites assessed, Farmington, New Mexico or Tonopah Airport, Nevada. Increasing the heliostat field collection area from 1000 to 1500 m 2 , led to an increase in the calculated daily rate

15. Aspen Plus simulation of biomass integrated gasification combined cycle systems at corn ethanol plants

International Nuclear Information System (INIS)

Zheng, Huixiao; Kaliyan, Nalladurai; Morey, R. Vance

2013-01-01

Biomass integrated gasification combined cycle (BIGCC) systems and natural gas combined cycle (NGCC) systems are employed to provide heat and electricity to a 0.19 hm 3 y −1 (50 million gallon per year) corn ethanol plant using different fuels (syrup and corn stover, corn stover alone, and natural gas). Aspen Plus simulations of BIGCC/NGCC systems are performed to study effects of different fuels, gas turbine compression pressure, dryers (steam tube or superheated steam) for biomass fuels and ethanol co-products, and steam tube dryer exhaust treatment methods. The goal is to maximize electricity generation while meeting process heat needs of the plant. At fuel input rates of 110 MW, BIGCC systems with steam tube dryers provide 20–25 MW of power to the grid with system thermal efficiencies (net power generated plus process heat rate divided by fuel input rate) of 69–74%. NGCC systems with steam tube dryers provide 26–30 MW of power to the grid with system thermal efficiencies of 74–78%. BIGCC systems with superheated steam dryers provide 20–22 MW of power to the grid with system thermal efficiencies of 53–56%. The life-cycle greenhouse gas (GHG) emission reduction for conventional corn ethanol compared to gasoline is 39% for process heat with natural gas (grid electricity), 117% for BIGCC with syrup and corn stover fuel, 124% for BIGCC with corn stover fuel, and 93% for NGCC with natural gas fuel. These GHG emission estimates do not include indirect land use change effects. -- Highlights: •BIGCC and natural gas combined cycle systems at corn ethanol plants are simulated. •The best performance results in 25–30 MW power to grid. •The best performance results in 74–78% system thermal efficiencies. •GHG reduction for corn ethanol with BIGCC systems compared to gasoline is over 100%

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

International Nuclear Information System (INIS)

Lee, Chan; Lee, Jin Wook; Kwon, Tae Wan; Kim, Gyoo Tae

2014-01-01

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

17. Technical and economical optimization of wood gasification in a circulating fluidized bed. Final report; Technische und wirtschaftliche Optimierung der Vergasung von Holz in der zirkulierenden Wirbelschicht. Abschlussbericht

Energy Technology Data Exchange (ETDEWEB)

Ising, M.; Unger, C.; Heunemann, F.; Dinkelbach, L.

2002-12-01

The project's objective was the optimization of a novel process for high efficient combined heat and power production from solid biomass. The processed air blown wood gasification in a pilot scale circulating fluidized bed was added by a catalytic tar reformer which would yield a tar-free gas quality suitable for IC-engine operation. Major efforts were taken for technical improvement of the tar reformer, especially concerning temperature control and cleaning devices which is important for keeping constantly a high activity. Pure natural timber did not yield chemical deactivation at the catalyst whereas the gasification of waste wood yielded decreasing activity which could be partly reversed by special measures taken. Further optimization of the process considered a better automation and improvement of the engine's flue gas emissions. Also a detailed economic consideration and evaluation of the entire process has been carried out. As a result the novel process should have economic advantages compared with conventional technology. (orig.) [German] Gegenstand des Vorhabens war die Weiterentwicklung eines Verfahrens zur effizienteren Strom- und Waermegewinnung aus festen Biobrennstoffen. Durch luftgeblasene Vergasung von Holz im Pilotmassstab in einer zirkulierenden Wirbelschicht und anschliessender katalytischer Teerspaltung konnte ein niederkalorisches Brenngas erzeugt werden, welches zum Betrieb eines Motoren-Blockheizkraftwerks geeignet war. Im Rahmen der Verfahrensoptimierung wurde der katalytische Teer-Reformer, insbesondere in Bezug auf Temperaturfuehrung und die zum Aktivitaetserhalt wichtige Abreinigungsvorrichtung, verbessert. Bei der Vergasung von Naturholz wurde keine chemische Desaktivierung festgestellt. Beim Altholzeinsatz wurde ein ueberwiegend reversibler Aktivitaetsverlust verzeichnet und begruendet. Geeignete Gegenmassnahmen wurden untersucht und beschrieben. Weitere Optimierungen betrafen die Anlagensteuerungstechnik im Hinblick auf die

18. Fluidized bed gasification of the fuel fraction of municipal solid wastes; Gasificacion en lecho fluidizado de la fraccion combustible de los residuos solidos urbanos

Energy Technology Data Exchange (ETDEWEB)

Fernandez, J.; Baldasano, J. M.; Gasso, S. [Universidad Politecnica de Cataluna. Barcelona (Spain)

1998-12-31

In this paper, the results obtained in the application of the fluidized-bed gasification to the treatment of solid waste with high heating value. These wastes could be valuable materials in thermo conversion processes such as gasification. The combustible fraction of municipal solid waste (MSW) composed of paper, cardboard, plastics (PET,PVC), referred as refuse derived fuel (RDF), has been considered in this work. The experimental facility consists of an air-blown gasifier operating at atmospheric pressure with a capacity of 50 kg/h. The results obtained show that the gasification of RDF allows to produce a gas with a high heating value (HHV) of 7.8 Mj/Mn3 and recovering more than 80% of the initial HHV of the waste in the cold gas. Solid residue produced in the gasification process is lower than 10% of the initial waste. (Author)

19. Role of steel slags on biomass/carbon dioxide gasification integrated with recovery of high temperature heat.

Science.gov (United States)

Sun, Yongqi; Liu, Qianyi; Wang, Hao; Zhang, Zuotai; Wang, Xidong

2017-01-01

Disposal of biomass in the agriculture and steel slags in the steel industry provides a significant solution toward sustainability in China. Herein these two sectors were creatively combined as a novel method, i.e., biomass/CO 2 gasification using waste heat from hot slags where the influence of chemical compositions of steel slags, characterized as iron oxide content and basicity, on gasification thermodynamics, was systemically reported for the first time. Both the target gases of CO, H 2 and CH 4 and the polluted gases of NH 3 , NO and NO 2 were considered. It was first found that an increasing iron content and slag basicity continuously improved the CO yield at 600-1000°C and 800-1000°C, respectively; while the effect on polluted gas releases was limited. Moreover, the solid wastes after gasification could be utilized to provide nutrients and improve the soil in the agriculture, starting from which an integrated modern system was proposed herein. Copyright © 2016 Elsevier Ltd. All rights reserved.

20. Biomass gasification bottom ash as a source of CaO catalyst for biodiesel production via transesterification of palm oil

International Nuclear Information System (INIS)

Maneerung, Thawatchai; Kawi, Sibudjing; Wang, Chi-Hwa

2015-01-01

Highlights: • CaO catalyst was successfully developed from wood gasification bottom ash. • CaCO 3 in bottom ash can be converted to CaO catalyst by calcination. • CaO catalysts derived from bottom ash exhibited high activity towards transesterification. • CaO catalysts derived from bottom ash can be reutilized up to four times. - Abstract: The main aim of this research is to develop environmentally and economically benign heterogeneous catalysts for biodiesel production via transesterification of palm oil. For this propose, calcium oxide (CaO) catalyst has been developed from bottom ash waste arising from woody biomass gasification. Calcium carbonate was found to be the main component in bottom ash and can be transformed into the active CaO catalyst by simple calcination at 800 °C without any chemical treatment. The obtained CaO catalysts exhibit high biodiesel production activity, over 90% yield of methyl ester can be achieved at the optimized reaction condition. Experimental kinetic data fit well the pseudo-first order kinetic model. The activation energy (E a ) of the transesterification reaction was calculated to be 83.9 kJ mol −1 . Moreover, the CaO catalysts derived from woody biomass gasification bottom ash can be reutilized up to four times, offering the efficient and low-cost CaO catalysts which could make biodiesel production process more economic and environmental friendly

1. Microwave-driven plasma gasification for biomass waste treatment at miniature scale

NARCIS (Netherlands)

Sturm, G.S.J.; Navarrete Muñoz, A.; Purushothaman Vellayani, A.; Stefanidis, G.

2016-01-01

Gasification technology may combine waste treatment with energy generation. Conventional gasification processes are bulky and inflexible. By using an external energy source, in the form of microwave-generated plasma, equipment size may be reduced and flexibility as regards to the feed composition

2. Techno-economic assessment of catalytic gasification of biomass powders for methanol production.

Science.gov (United States)

Carvalho, Lara; Furusjö, Erik; Kirtania, Kawnish; Wetterlund, Elisabeth; Lundgren, Joakim; Anheden, Marie; Wolf, Jens

2017-08-01

This study evaluated the techno-economic performance and potential benefits of methanol production through catalytic gasification of forest residues and lignin. The results showed that while catalytic gasification enables increased cold gas efficiencies and methanol yields compared to non-catalytic gasification, the additional pre-treatment energy and loss of electricity production result in small or no system efficiency improvements. The resulting required methanol selling prices (90-130€/MWh) are comparable with production costs for other biofuels. It is concluded that catalytic gasification of forest residues can be an attractive option as it provides operational advantages at production costs comparable to non-catalytic gasification. The addition of lignin would require lignin costs below 25€/MWh to be economically beneficial. Copyright © 2017 Elsevier Ltd. All rights reserved.

3. Simulated performance of biomass gasification based combined power and refrigeration plant for community scale application

Energy Technology Data Exchange (ETDEWEB)

Chattopadhyay, S., E-mail: suman.mech09@gmail.com [Department of Mechanical Engineering, NIT, Agarpara, Kolkata – 700109, West Bengal (India); Mondal, P., E-mail: mondal.pradip87@gmail.com; Ghosh, S., E-mail: sudipghosh.becollege@gmail.com [Department of Mechanical Engineering, IIEST, Shibpur, Howrah – 711103, West Bengal (India)

2016-07-12

Thermal performance analysis and sizing of a biomass gasification based combined power and refrigeration plant (CPR) is reported in this study. The plant is capable of producing 100 kWe of electrical output while simultaneously producing a refrigeration effect, varying from 28-68 ton of refrigeration (TR). The topping gas turbine cycle is an indirectly heated all-air cycle. A combustor heat exchanger duplex (CHX) unit burns producer gas and transfer heat to air. This arrangement avoids complex gas cleaning requirements for the