THERMAL SCIENCE

International Scientific Journal

PRESSURISED FLUIDISED BED GASIFICATION EXPERIMENTS OF BIOMASS AND FOSSIL FUELS

ABSTRACT
Gasification of biomass and older fossil fuels, like brown coal, hot gas cleanup using a ceramic filter and combustion of LCV product gas in a combustor was performed using a 1.5 [MWth] test rig (PFBG) at Delft University and a 10-50 [kWth] at Stuttgart University (DWSA) in the framework of experimental pilot plant research on efficient, environmentally acceptable large scale power generation systems based on fluidised bed gasification technology. The influence of operating conditions (pressure, temperature, stoichiometric ratio) on gasification performance (gas composition, conversion grades) was studied. The gasifiers were operated at pressures in a range of 0.15 - 1.0 [MPa] and maximum temperatures of circa 900 [°C]. The Delft gasifier has a 2 [m] high bed zone (diameter of 0.4 [m]) followed by a freeboard approximately 4 m high (diameter of 0.5 m). The IVD gasifier has a diameter of 0.1 [m] and has a total reactor length of 4 [m]. Both gasifiers are equipped with a hot gas cleanup ceramic filter and a pressurised combustor. Measurements are compared with a model based on homogeneous elementary reaction chemistry and heterogeneous gas-char reactions related to emission of environmentally harmful components like fuel-nitrogen derived species. Results obtained are presented and analysed. Carbon conversions were well above 80 [%]. Fuel-nitrogen conversion to ammonia is above ca. 50 [%] and the highest for biomass in comparison to solid fossil fuel. The results are in-line with other pressurised fluidised bed gasification investigations with bottom feeding of biomass. Significant deviation with top feeding occurs. Measurements and model were in quite good agreement with each other.
KEYWORDS
PAPER SUBMITTED: 2001-12-20
PAPER REVISED: 2002-03-10
PAPER ACCEPTED: 2002-05-15
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THERMAL SCIENCE YEAR 2001, VOLUME 5, ISSUE 2, PAGES [69 - 81]
REFERENCES
  1. Kwant K.W. &Leenders C. (1999) Development of green energy market in the Netherlands and the perspectives of biomass, in: Proceedings of the fourth biomass conference of the Americas, (Eds. R.P. Overend &E. Chornet), pp. 1629. Elsevier Science Ltd., Oxford.
  2. Nagel H., Spliethoff H.&Hein K.R.G.(1997) Untersuchungen zum Einfluss des Hybridkonzeptes auf den Betrieb einer Druckwirbelschicht (in German) Research into the influence of the hybrid concept on operation of a pressurised fluidised bed. In: Proceedings of the VGB conference: "Forschung der Kraftwerkstechnik 1998", C5, pp.1-18.Essen.
  3. Brage C., Yu Q., Chen, G. and Sjöström K. (1997) Use of amino phase adsorbent for biomass tar sampling and separation. Fuel, 76 (2), pp. 137-42.
  4. Kurkela E. (1996) Formation and removal of biomass -derived contaminants in fluidized-bed gasification processes, VTT publications report No. 287, VTT, Espoo, Finland.
  5. Lepp?lahti J. & Koljonen T. (1995) Nitrogen evolution from coal, peat and wood during gasification: literature review. Fuel Processing Technology, 43, pp. 1-45.
  6. Zhou J. (1998) Fuel-bound Nitrogen evolution during biomass gasification. PhD thesis, University of Hawaii, United States of America.
  7. Chen G. (1998) The reactivity of char from rapid heating processes under pressure; the role of the time-temperature-environment history of it's formation. PhD thesis, Royal Institute of Technology Stockholm. Sweden.
  8. de Jong W., Andries J. &Hein K.R.G. (1999) Coal/Biomass co-gasification in a Pressurised Fluidised Bed Reactor. Renewable Energy, 16, pp. 1110-1114.
  9. Hoppesteyn P.D.J. (1999) Application of Low Calorific Value Gaseous Fuels in Gas Turbine Combustors, PhD thesis, Delft University Press, Technical University Delft, Department of Mechanical Engineering & Marine Technology, The Netherlands.
  10. Simell P., Stahlberg P., Kurkela E., Albrecht J., Deutsch, S. &Sj?ström K. (2000) Provisional protocol for the sampling and analysis of tar and particulates in the gas from large-scale biomass gasifiers. Version 1998. Biomass & Bioenergy, 18 (1), pp.19-38.
  11. Milne T.A., Abatzoglou N. & Evans R.J. (1998) Biomass Gasifier Tars: Their Nature, Formation and Conversion, IEA Biomass Utilization Task XIII, "Thermal Gasification of Biomass", activity report NREL/TP-570-25357, Golden, Colorado, USA.
  12. Kurkela E., Laatikainen-Luntama J., Ståhlberg P. & Moilanen A., (1996) Pressurised fluidised-bed gasification experiments with biomass, peat and coal at VTT in 1991-1994, part 3. Gasification of Danish wheat straw and coal. VTT publications report No. 291, VTT, Espoo, Finland.
  13. Vriesman, P., Heginuz, E. and Sjöström, K. (2000) Biomass gasification in a laboratory - scale AFBG: influence of the location of the feeding point on the fuel-N conversion, Fuel, 79, pp. 1371-1378.
  14. Bergsma G., Crouzen H., de Weerd G. and van der Werff, T. (1999) Beperking van emissies naar de lucht bij conversie van biomassa naar elektriciteit en warmte (in Dutch) Limitation of emissions to the air by conversion of biomass into electricity and heat, Centrum voor energiebesparing en schone technologie, The Netherlands, Delft.

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