Advertisement

Modeling Biomass Gasification Using Thermodynamic Equilibrium Approach

  • Hua-Jiang Huang
  • Shri RamaswamyEmail author
Article

Abstract

In this paper, the thermodynamic equilibrium models for biomass gasification applicable to various gasifier types have been developed, with and without considering char. The equilibrium models were then modified closely matching the CH4 only or both CH4 and CO compositions from experimental data. It is shown that the modified model presented here based on thermodynamic equilibrium and taking into account local heat and mass considerations can be used to simulate the performance of a downdraft gasifier. The model can also be used to estimate the equilibrium composition of the syngas. Depending on the gasifier type and internal fluid flow, heat and mass transfer characteristics, with proper modification of the equilibrium model, a simple tool to simulate the operation and performance of varying types of biomass gasifier can be developed.

Keywords

Biomass Gasification Chemical equilibrium Modeling Downdraft gasifier Syngas 

Nomenclature

a

number of atom H in the biomass formula CH a O b N c S d based on 1 mol of carbon

A

coefficients of the heat capacity formula

ΔA

change in coefficient A of a reaction, see formula 17

b

number of atom O in the biomass formula CH a O b N c S d

B

coefficients of the heat capacity formula

ΔB

change in coefficient B of a reaction, similar to formula 17

c

number of atom N in the biomass formula CH a O b N c S d

C

coefficients of the heat capacity formula

CP

heat capacity, J/mol·K

ΔC

change in coefficient C of a reaction, similar to formula 17

d

number of atom S in the biomass formula CH a O b N c S d

D

coefficients of the heat capacity formula

ΔD

change in coefficient D of a reaction, similar to formula 17

e

stoichiometric coefficient of H2O (liquid) in the overall gasification reaction 1

E

coefficients of the heat capacity formula

f

stoichiometric coefficient O2 in the overall gasification reaction 1

g

stoichiometric coefficient N2 in the overall gasification reaction 1

ΔG0

standard Gibbs free-energy change of a reaction at 298.15 K, J/kmol

\(\Delta G_{fi}^0 \)

Gibbs energy of formation of component i at 298.15 K, J/mol

\(\Delta H_{T_0 }^0 \)

standard heat of reaction at temperature of T 0 (=298.15 K), J/mol

ni

represents the mole numbers of H2, CO, CH4, CO2, H2O(g) and C(s), i = 1,2,…6

K0

equilibrium constant at 298.15 K

Ki

equilibrium constants of the three equilibrium reactions 5–7

Pt

the total pressure in the reaction system, Pa

R

ideal gas constant

T0

reference temperature, T 0 = 298.15 K

T

reaction temperature, K

Superscript

°

standard state for property values

Notes

Acknowledgment

The University of Minnesota Initiative for Renewable Energy and the Environment (IREE) is gratefully acknowledged for its financial support.

References

  1. 1.
    Report of Pacific Northwest National Laboratory (PNNL) & National Renewable Energy Laboratory (NREL). (2004). Available from: http://www1.eere.energy.gov/biomass/pdfs/35523.pdf. Accessed at 20 May 2008
  2. 2.
    Bremaud, M., Fongarland, P., Anfray, J., Jallais, S., Schweich, D., & Khodakov, A. Y. (2005). Influence of syngas composition on the transient behavior of a Fischer–Tropsch continuous slurry reactor. Catalysis Today, 106, 137–142. doi: 10.1016/j.cattod.2005.07.126.CrossRefGoogle Scholar
  3. 3.
    Khodakov, A. Y., Chu, W., & Fongarland, P. (2007). Advances in the development of novel cobalt Fischer–Tropsch catalysts for synthesis of long-chain hydrocarbons and clean fuels. Chemical Reviews, 107, 1692–1744. doi: 10.1021/cr050972v.CrossRefGoogle Scholar
  4. 4.
    Martínez, A., Valencia, S., Murciano, R., Cerqueira, H. S., Costa, A. F., & Aguiar, E. F. S. (2008). Catalytic behavior of hybrid Co/SiO2-(medium-pore) zeolite catalysts during the one-stage conversion of syngas to gasoline. Applied Catalysis A General, 346(1–2), 117–125. doi: 10.1016/j.apcata.2008.05.015.CrossRefGoogle Scholar
  5. 5.
    Ogawa, T., Inoue, N., Shikada, T., & Ohno, Y. (2003). Direct dimethyl ether synthesis. Journal of Natural Gas Chemistry, 12, 219–227.Google Scholar
  6. 6.
    Bae, J. W., Potdar, H. S., Kang, S. H., & Jun, K. W. (2008). Coproduction of methanol and dimethyl ether from biomass-derived syngas on a Cu–ZnO–Al2O3/γ-Al2O3 hybrid catalyst. Energy & Fuels, 22, 223–230. doi: 10.1021/ef700461j.CrossRefGoogle Scholar
  7. 7.
    Xiaoming, M., Guodong, L., & Hongbin, Z. (2006). Co–Mo–K sulfide-based catalyst promoted by multiwalled carbon nanotubes for higher alcohol synthesis from syngas. Chinese Journal of Catalysis, 27(11), 1019–1027. doi: 10.1016/S1872-2067(06)60053-3.CrossRefGoogle Scholar
  8. 8.
    National Non-Food Crops Centre (NNFCC). Report of a DTI Global Watch Mission, 2006. Available from: www.oti.globalwatchonline.com/online_pdfs/36610MR.pdf. Accessed May 19, 2008.
  9. 9.
    Larson, E. D. Biomass gasification systems for electric power, cogeneration, liquid fuels, and hydrogen. gcep biomass energy workshop. 27 April 2004 Available from: http://gcep.stanford.edu/pdfs/energy_workshops_04_04/biomass_larson.pdf
  10. 10.
    Turn, S., Kinoshita, C., Zhang, Z., Ishimura, D., & Zhou, J. (1998). International Journal of Hydrogen Energy, 23(8), 641–648. doi: 10.1016/S0360-3199(97)00118-3.CrossRefGoogle Scholar
  11. 11.
    Dogru, M., Howarth, C. R., Akay, G., Keskinler, B., & Malik, A. A. (2002). Energy, 27, 415–427. doi: 10.1016/S0360-5442(01)00094-9.CrossRefGoogle Scholar
  12. 12.
    Jayah, T. H., Aye, L., Fuller, R. J., & Stewart, D. F. (2003). Biomass and Bioenergy, 25, 459–469. doi: 10.1016/S0961-9534(03)00037-0.CrossRefGoogle Scholar
  13. 13.
    Asadullah, M., et al. (2004). Gasification of different biomasses in a dual-bed gasifier system combined with novel catalysts with high energy efficiency. Applied Catalysis A General, 267, 95–102. doi: 10.1016/j.apcata.2004.02.028.CrossRefGoogle Scholar
  14. 14.
    Filippis, P. D., Borgianni, C., Paolucci, M., & Pochetti, F. (2004). Biomass and Bioenergy, 27, 247–252. doi: 10.1016/j.biombioe.2003.11.009.CrossRefGoogle Scholar
  15. 15.
    Radmanesh, R., Chaouki, J., & Guy, C. (2006). AIChE Journal. American Institute of Chemical Engineers, 52(12), 4258–4272. doi: 10.1002/aic.11020.Google Scholar
  16. 16.
    Li, X. T., Grace, J. R., Lim, C. J., Watkinson, A. P., Chen, H. P., & Kim, J. R. (2004). Biomass gasification in a circulating fluidized bed. Biomass and Bioenergy, 26, 171–193. doi: 10.1016/S0961-9534(03)00084-9.CrossRefGoogle Scholar
  17. 17.
    Radmanesh, R., Chaouki, J., & Guy, C. (2006). Biomass gasification in a bubbling fluidized bed reactor: experiments and modeling. AIChE Journal. American Institute of Chemical Engineers, 52(12), 4258–4272. doi: 10.1002/aic.11020.Google Scholar
  18. 18.
    Pengmei, L. V., Yuan, Z., Ma, L., Wu, C., Chen, Y., & Zhu, J. (2007). Hydrogen-rich gas production from biomass air and oxygen/steam gasification in a downdraft gasifier. Renewable Energy, 32, 2173–2185. doi: 10.1016/j.renene.2006.11.010.CrossRefGoogle Scholar
  19. 19.
    Francisco, V. ,Tinaut, A. M., Pérez, J. F., & Horrillo, A. (2008). Effect of biomass particle size and air superficial velocity on the gasification process in a downdraft fixed bed gasifier. An experimental and modelling study. Fuel Processing Technology. doi: 10.1016/j.fuproc.2008.04.010.
  20. 20.
    Gao, N., & Li, A. (2008). Modeling and simulation of combined pyrolysis and reduction zone for a downdraft biomass gasifier. Energy Conversion and Management, 49, 3483–3490. doi: 10.1016/j.enconman.2008.08.002.CrossRefGoogle Scholar
  21. 21.
    Di Blasi, C., Branca, C., Sparano, S., & La Mantia, B. (2003). Drying characteristics of wood cylinders for conditions pertinent to fixed-bed countercurrent gasification. Biomass and Bioenergy, 25, 45–58. doi: 10.1016/S0961-9534(02)00180-0.CrossRefGoogle Scholar
  22. 22.
    Lucas, C., Szewczyk, _D., Blasiak, W., & Mochida, S. (2004). High-temperature air and steam gasification of densified biofuels. Biomass and Bioenergy, 27, 563–575. doi: 10.1016/j.biombioe.2003.08.015.CrossRefGoogle Scholar
  23. 23.
    Gao, N., Li, A., Quan, C., & Gao, F. (2008). Hydrogen-rich gas production from biomass steam gasification in an updraft fixed-bed gasifier combined with a porous ceramic reformer. International Journal of Hydrogen Energy, 33, 5430–5438. doi: 10.1016/j.ijhydene.2008.07.033.CrossRefGoogle Scholar
  24. 24.
    Gabra, M., Pettersson, E., Backman, R., & Kjellström, B. (2001). Evaluation of cyclone gasifer performance for gasification of sugar cane residue—part 1: gasification of bagasse. Biomass and Bioenergy, 21, 351–369. doi: 10.1016/S0961-9534(01)00043-5.CrossRefGoogle Scholar
  25. 25.
    Fletcher, D. F., Haynes, B. S., Christo, F. C., & Joseph, S. D. (2000). A CFD based combustion model of an entrained flow biomass gasifier. Applied Mathematical Modelling, 24, 165–182. doi: 10.1016/S0307-904X(99)00025-6.CrossRefGoogle Scholar
  26. 26.
    Kobayashi, N., Tanaka, M., Piao, G., Kobayashi, J., Hatano, S., Itaya, Y., et al. (2009). High temperature air-blown woody biomass gasification model for the estimation of an entrained down-flow gasifier. Waste Management, 29, 245–251. doi: 10.1016/j.wasman.2008.04.014.CrossRefGoogle Scholar
  27. 27.
    Beenackers, A. A. C. M. (1999). Biomass gasification in moving beds, a review of European technologies. Renewable Energy, 16, 1118–1186. doi: 10.1016/S0960-1481(98)00469-8.CrossRefGoogle Scholar
  28. 28.
    Yu, J., Tian, F.-J., McKenzie, L. J., & Li, C.-Z. (2006). Char-supported nano iron catalyst for water–gas-shift reaction: hydrogen production from coal/biomass gasification. Process Safety and Environmental Protection, 84(2), 125–130. doi: 10.1205/psep.05045.CrossRefGoogle Scholar
  29. 29.
    Di Blasi, C. (2000). Dynamic behaviour of stratified downdraft gasifiers. Chemical Engineering Science, 55, 2931–2944.CrossRefGoogle Scholar
  30. 30.
    Giltrap, D. L., McKibbin, R., & Barnes, G. R. G. (2003). A steady state model of gas–char reactions in a downdraft biomass gasifier. Solar Energy, 74, 85–91. doi: 10.1016/S0038-092X(03)00091-4.CrossRefGoogle Scholar
  31. 31.
    Mostoufi, N., Cui, H., & Chaouki, J. (2001). A comparison of two- and singlephase models for fluidized-bed reactors. Industrial & Engineering Chemistry Research, 40, 5526–5532. doi: 10.1021/ie010121n.CrossRefGoogle Scholar
  32. 32.
    Fletcher, D. F., Haynes, B. S., Chen, J., & Joseph, S. D. (1998). Computational fluid dynamics modelling of an entrained flow biomass gasifier. Applied Mathematical Modelling, 22, 747–757. doi: 10.1016/S0307-904X(98)10025-2.CrossRefGoogle Scholar
  33. 33.
    Gerun, L., Paraschiv, M., Vîjeu, R., Bellettre, J., Tazerout, M., Gøel, B., et al. (2008). Numerical investigation of the partial oxidation in a two-stage downdraft gasifier. Fuel, 87, 1383–1393. doi: 10.1016/j.fuel.2007.07.009.CrossRefGoogle Scholar
  34. 34.
    Mansaray, K. G., Al-Taweel, A. M., Ghaly, A. E., Hamdullahpur, F., & Ugursal, V. I. (2000). Energy Sources, 22, 83–98. doi: 10.1080/00908310050014243.CrossRefGoogle Scholar
  35. 35.
    Schuster, G., Löffler, G., Weigl, K., & Hofbauer, H. (2001). Bioresource Technology, 77, 71–79. doi: 10.1016/S0960-8524(00)00115-2.CrossRefGoogle Scholar
  36. 36.
    Zainal, Z. A., Ali, R., Lean, C. H., & Seetharamu, K. N. (2001). Energy Conversion and Management, 42, 1499–1515. doi: 10.1016/S0196-8904(00)00078-9.CrossRefGoogle Scholar
  37. 37.
    Mountouris, A., Voutsas, E., & Tassios, D. (2006). Energy Conversion and Management, 47, 1723–1737. doi: 10.1016/j.enconman.2005.10.015.CrossRefGoogle Scholar
  38. 38.
    Melgar, A., Pérez, J. F., Laget, H., & Horillo, A. (2007). Energy Conversion and Management, 48, 59–67. doi: 10.1016/j.enconman.2006.05.004.CrossRefGoogle Scholar
  39. 39.
    Jarungthammachote, S., & Dutta, A. (2007). Energy, 32, 1660–1669. doi: 10.1016/j.energy.2007.01.010.CrossRefGoogle Scholar
  40. 40.
    Li, X., Grace, J. R., Watkinson, A. P., Lim, C. J., & Ergüdenler, A. (2001). Fuel, 80, 195–207. doi: 10.1016/S0016-2361(00)00074-0.CrossRefGoogle Scholar
  41. 41.
    Mahishi, M. R., & Goswami, D. Y. (2007). International Journal of Hydrogen Energy, 29, 1123–1131.Google Scholar
  42. 42.
    Altafini, C. R., Wander, P. R., & Barreto, R. M. (2003). Energy Conversion and Management, 44, 2763–2777.CrossRefGoogle Scholar
  43. 43.
    Yaws, C. L. (1999). Chemical properties handbook. New York: McGraw-Hill.Google Scholar

Copyright information

© Humana Press 2008

Authors and Affiliations

  1. 1.Department of Bioproducts and Biosystems EngineeringUniversity of MinnesotaSt. PaulUSA

Personalised recommendations