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

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

[1]  D. D. Perlmutter,et al.  A random pore model for fluid‐solid reactions: I. Isothermal, kinetic control , 1980 .

[2]  W. Peters,et al.  Product compositions in rapid hydropyrolysis of coal , 1980 .

[3]  Y. Çengel,et al.  Thermodynamics : An Engineering Approach , 1989 .

[4]  A. Sarofim,et al.  Coal devolatilization at high temperatures , 1977 .

[5]  Hiroaki Watanabe,et al.  Numerical simulation of coal gasification in entrained flow coal gasifier , 2006 .

[6]  Adel F. Sarofim,et al.  CFD Modeling For Entrained Flow Gasifiers , 2002 .

[7]  S. Niksa,et al.  Global rates of devolatilization for various coal types , 1993 .

[8]  Alan Williams,et al.  A simulation study on the performance of an entrained-flow coal gasifier , 1995 .

[9]  P. R. Solomon,et al.  Coal thermal decomposition in an entrained flow reactor: Experiments and theory , 1982 .

[10]  Rakesh Govind,et al.  Modeling and simulation of an entrained flow coal gasifier , 1984 .

[11]  Caixia Chen,et al.  Numerical simulation of entrained flow coal gasifiers. Part I: modeling of coal gasification in an entrained flow gasifier , 2000 .

[12]  Andrew Charles Beath.  Mathematical Modelling of Entrained Flow Coal Gasification , 1996 .

[13]  Normand M. Laurendeau,et al.  Heterogeneous Kinetics of Coal Char Gasification and Combustion , 1979 .

[14]  Hiromitsu Matsuda,et al.  Gasification rate analysis of coal char with a pressurized drop tube furnace , 2002 .

[15]  Despina Vamvuka,et al.  Modelling of an entrained flow coal gasifier. 1. Development of the model and general predictions , 1995 .

[16]  S. Niksa.  Predicting the Devolatilization Behavior of any coal from its ultimate analysis , 1995 .

[17]  Shiro Kajitani,et al.  CO2 gasification rate analysis of coal char in entrained flow coal gasifier , 2006 .