Yan Q.-X.,Shanxi Institute of Coal CAS Chemistry |
Yan Q.-X.,University of Chinese Academy of Sciences |
Yan Q.-X.,National key laboratory of Coal Conversion |
Li F.-H.,Heze College |
And 9 more authors.
Huaxue Gongcheng/Chemical Engineering (China) | Year: 2014
The pressurized coal-char CO2 gasification kinetics was investigated under total pressure up to 2.0 MPa by using self-made pressurized fixed bed reactor. The effects of different CO2 partial pressure, total pressure and char types on the gasification rate, and the effects of the total pressure on the parameters of the nth-order rate equation and the L-H rate equation were discussed. The results show that the homogeneous kinetic model is more suitable for the HLH lignite char-CO2 gasification reaction, and the random pore model is more suitable for the SM char-CO2 gasification reaction; char gasification rate increases with the increasing of CO2 partial pressure at a constant total pressure, and it decreases with the increasing of total pressure at a constant CO2 partial pressure; for the nth-order rate equation, reaction order with respect to CO2 decreases with the increasing of total pressure, and for the L-H rate equation, the rate constant k1 decreases with the increasing of total pressure, while the rate constant k3 increases with the increase of total pressure. In order to predict easily the coal-char gasification rate with CO2, a simple experiential rate equation was proposed.