Modeling Drying and Pyrolysis of Moist Wood Particles at Slow Heating Rates
Formulation for drying and pyrolysis process in packed beds at slow heating rates is presented. Drying of biomass particles bed is described by mass diffusion equation and local moisture-vapour-equilibrium relations. In gasifiers, volatilization rate during pyrolysis of biomass is modeled by using apparent kinetic rate expression, while product compositions at slow heating rates is modeled using empirical fitted mass ratios (i.e., CO/CO2, ME/CO2, H2O/CO2) in terms of pyrolysis temperature. The drying module is validated fairly with available chemical kinetics scheme and found that the testing zone in gasifier bed constituted of relatively smaller particles having high airflow with high isothermal temperature expedite the drying process. Further, volatile releases more quickly within the shorter zone height at high temperatures (isothermal). Both, moisture loss and volatile release profiles are found to be sensitive to temperature, although the influence of initial moisture content on volatile release profile is not so sensitive.
[1] Gronli M.G., Melaaen M.C., (2000), Mathematical model for wood pyrolysis- Comparison of experimental measurements with model predictions, Energy & Fuels, 14, 791-800.
[2] Galgano A., Di Blasi, C., (2004), Modeling the propagation of drying and decomposition fronts in wood, Combustion and Flame, 139, 16-27.
[3] Bryden K.M., Ragland K.W., Rutland C.J., (2002), Modeling thermally thick pyrolysis of wood, Biomass and Bioenergy, 22, 41-53.
[4] Baronas R., Lvanauskas F., Juodeikiene I., Kajalavicius A., (2001) Modelling of moisture movement in wood during outdoor storage, Nonlinear Analysis: Modelling and Control, 6, 2, 3-14.
[5] Gronli M.G., Melaaen M.C., (1997), Modelling and simulation of moist wood drying and pyrolysis, Developments in Thermochemical Biomass Conversion, Bridgewater, A.V. Boocock, (Eds.), 132-46.
[6] Di Blasi C., (2000), Simultaneous heat, mass and momentum transfer during biomass drying, in: Bridgewater, A.V., Boocock, (Ed.), Developments in thermochemical biomass conversion, 117-31.
[7] Di Blasi C, (1993), Modelling and simulation of combustion processes of charring and non-charring solid fuels, Prog. Energy Combust. Sci., 19, 71-104.
[8] Di Blasi C., (1998), Comparison of semi-global mechanisms for primary pyrolysis of lignocellulosic fuels, Journal of Analytical and Applied Pyrolysis, 47, 43-64.
[9] Thunman H., Niklasson F., Johnson F., Leckner B., (2001), Composition of volatile gases and thermochemical properties of wood for modelling of fixed or fluidized beds, Energy & Fuel, 15 1488-497.
[10] Grobski M., Bain R., (1981), Properties of biomass relevant to gasification, In: T.B. Reed (Eds.), Biomass gasification: Principles & Technology: Energy Technology, Solar Energy Research Inst. (SERI), 41-70.
[11] Sharma Avdhesh Kr., Ravi M.R., Kohli S.,(2006) Modelling Product composition in slow pyrolysis of wood, Journal of Solar Energy Society of India(SESI), 16, 1, 1-11.
[12] Borman G.L., Ragland K.W., (1998), Combustion Engineering, McGraw-Hill International Editions.
[13] McCabe W.L., Smith J.C., Harriott P., (1993), Unit Operations of Chemical Engineering, 5th Ed., McGraw-Hill Inc., NY, USA.
[14] Simpson W.T.,(1993), Determination and use of moisture diffusion coefficient to characterize drying of northern red oak (Quercus rubra), Wood Sc. & Tech., 27, 409-20.
[15] Simpson, W.T., (1998) Equilibrium moisture content of wood in outdoor locations in the United States and Worldwide, Research note FPL-RN-0268, Forest Products Laboratory, United States Department of Agriculture, USA, 1998.
[16] Stull D.R., (1947), Vapor pressure of pure substances organic compounds, Ind. Eng. Chem., 39(1947) 517-540.
[17] Liu C.T., Lindsay W.T., (1970), Vapor pressure of D2O from 106 to 300C, J. Chem. Eng. Data, 15, 4, 510-13.
[18] NIST, (2005), NIST Chemistry WebBook, http://webbook.nist.gov
[19] Chan W.R., Kelbon M., Krieger B.B., (1985), Modeling and experimental verification of physical and chemical processes during pyrolysis of a large biomass particle, Fuel, 64,1505-13
[20] Sinha S., Jhalani A., Ravi M.R., Ray A., (2000), Modelling of pyrolysis in wood: A review, Journal of the Solar Energy Society of India (SESI), 10, 1, 41-62.
[21] Robert A.F. (1970), A review of kinetics data for pyrolysis of wood and related substances, Combustion and Flame, 14, 263-72.
[22] Sharma Avdhesh Kr., (2006) Simulation of Gasifier-Engine System, Ph.D. Thesis, IIT, Delhi.
[23] Zaror C.A., Pyle D.L., (1982), The Pyrolysis of biomass: A general review, Proc. Indian Acad. Science (Engg. Science), 5, 269-85. G. O. Young, “Synthetic structure of industrial plastics (Book style with paper title and editor),” in Plastics, 2nd ed. vol. 3, J. Peters, Ed. New York: McGraw-Hill, 1964, pp. 15–64.
[24] Tillman D.A., Rossi A.M., Kitto W.A., (1981), Wood Combustion, Academic Press Inc.
[25] Zanzi R.V., (2001), Pyrolysis of Biomass: Rapid pyrolysis at high temperature; slow pyrolysis for active carbon preparation, Dissertation, Department of Chemical Engineering and Technology, Chemical Technology, Royal Institute of Technology, Stockholm, Sweden.
[26] Boroson M.L., Howard J.B., Longwell J.P., Peters W.A., (1989), Product yields and kinetics from the vapour phase cracking of wood pyrolysis tars, AIChE Journal, 35, 1, 120-28.
[1] Gronli M.G., Melaaen M.C., (2000), Mathematical model for wood pyrolysis- Comparison of experimental measurements with model predictions, Energy & Fuels, 14, 791-800.
[2] Galgano A., Di Blasi, C., (2004), Modeling the propagation of drying and decomposition fronts in wood, Combustion and Flame, 139, 16-27.
[3] Bryden K.M., Ragland K.W., Rutland C.J., (2002), Modeling thermally thick pyrolysis of wood, Biomass and Bioenergy, 22, 41-53.
[4] Baronas R., Lvanauskas F., Juodeikiene I., Kajalavicius A., (2001) Modelling of moisture movement in wood during outdoor storage, Nonlinear Analysis: Modelling and Control, 6, 2, 3-14.
[5] Gronli M.G., Melaaen M.C., (1997), Modelling and simulation of moist wood drying and pyrolysis, Developments in Thermochemical Biomass Conversion, Bridgewater, A.V. Boocock, (Eds.), 132-46.
[6] Di Blasi C., (2000), Simultaneous heat, mass and momentum transfer during biomass drying, in: Bridgewater, A.V., Boocock, (Ed.), Developments in thermochemical biomass conversion, 117-31.
[7] Di Blasi C, (1993), Modelling and simulation of combustion processes of charring and non-charring solid fuels, Prog. Energy Combust. Sci., 19, 71-104.
[8] Di Blasi C., (1998), Comparison of semi-global mechanisms for primary pyrolysis of lignocellulosic fuels, Journal of Analytical and Applied Pyrolysis, 47, 43-64.
[9] Thunman H., Niklasson F., Johnson F., Leckner B., (2001), Composition of volatile gases and thermochemical properties of wood for modelling of fixed or fluidized beds, Energy & Fuel, 15 1488-497.
[10] Grobski M., Bain R., (1981), Properties of biomass relevant to gasification, In: T.B. Reed (Eds.), Biomass gasification: Principles & Technology: Energy Technology, Solar Energy Research Inst. (SERI), 41-70.
[11] Sharma Avdhesh Kr., Ravi M.R., Kohli S.,(2006) Modelling Product composition in slow pyrolysis of wood, Journal of Solar Energy Society of India(SESI), 16, 1, 1-11.
[12] Borman G.L., Ragland K.W., (1998), Combustion Engineering, McGraw-Hill International Editions.
[13] McCabe W.L., Smith J.C., Harriott P., (1993), Unit Operations of Chemical Engineering, 5th Ed., McGraw-Hill Inc., NY, USA.
[14] Simpson W.T.,(1993), Determination and use of moisture diffusion coefficient to characterize drying of northern red oak (Quercus rubra), Wood Sc. & Tech., 27, 409-20.
[15] Simpson, W.T., (1998) Equilibrium moisture content of wood in outdoor locations in the United States and Worldwide, Research note FPL-RN-0268, Forest Products Laboratory, United States Department of Agriculture, USA, 1998.
[16] Stull D.R., (1947), Vapor pressure of pure substances organic compounds, Ind. Eng. Chem., 39(1947) 517-540.
[17] Liu C.T., Lindsay W.T., (1970), Vapor pressure of D2O from 106 to 300C, J. Chem. Eng. Data, 15, 4, 510-13.
[18] NIST, (2005), NIST Chemistry WebBook, http://webbook.nist.gov
[19] Chan W.R., Kelbon M., Krieger B.B., (1985), Modeling and experimental verification of physical and chemical processes during pyrolysis of a large biomass particle, Fuel, 64,1505-13
[20] Sinha S., Jhalani A., Ravi M.R., Ray A., (2000), Modelling of pyrolysis in wood: A review, Journal of the Solar Energy Society of India (SESI), 10, 1, 41-62.
[21] Robert A.F. (1970), A review of kinetics data for pyrolysis of wood and related substances, Combustion and Flame, 14, 263-72.
[22] Sharma Avdhesh Kr., (2006) Simulation of Gasifier-Engine System, Ph.D. Thesis, IIT, Delhi.
[23] Zaror C.A., Pyle D.L., (1982), The Pyrolysis of biomass: A general review, Proc. Indian Acad. Science (Engg. Science), 5, 269-85. G. O. Young, “Synthetic structure of industrial plastics (Book style with paper title and editor),” in Plastics, 2nd ed. vol. 3, J. Peters, Ed. New York: McGraw-Hill, 1964, pp. 15–64.
[24] Tillman D.A., Rossi A.M., Kitto W.A., (1981), Wood Combustion, Academic Press Inc.
[25] Zanzi R.V., (2001), Pyrolysis of Biomass: Rapid pyrolysis at high temperature; slow pyrolysis for active carbon preparation, Dissertation, Department of Chemical Engineering and Technology, Chemical Technology, Royal Institute of Technology, Stockholm, Sweden.
[26] Boroson M.L., Howard J.B., Longwell J.P., Peters W.A., (1989), Product yields and kinetics from the vapour phase cracking of wood pyrolysis tars, AIChE Journal, 35, 1, 120-28.
@article{"International Journal of Chemical, Materials and Biomolecular Sciences:78843", author = "Avdhesh K. Sharma", title = "Modeling Drying and Pyrolysis of Moist Wood Particles at Slow Heating Rates", abstract = "Formulation for drying and pyrolysis process in packed beds at slow heating rates is presented. Drying of biomass particles bed is described by mass diffusion equation and local moisture-vapour-equilibrium relations. In gasifiers, volatilization rate during pyrolysis of biomass is modeled by using apparent kinetic rate expression, while product compositions at slow heating rates is modeled using empirical fitted mass ratios (i.e., CO/CO2, ME/CO2, H2O/CO2) in terms of pyrolysis temperature. The drying module is validated fairly with available chemical kinetics scheme and found that the testing zone in gasifier bed constituted of relatively smaller particles having high airflow with high isothermal temperature expedite the drying process. Further, volatile releases more quickly within the shorter zone height at high temperatures (isothermal). Both, moisture loss and volatile release profiles are found to be sensitive to temperature, although the influence of initial moisture content on volatile release profile is not so sensitive.
", keywords = "Modeling downdraft gasifier, drying, pyrolysis, moist woody biomass. ", volume = "13", number = "6", pages = "243-8", }
