A Modified Random Pore Model for the Kinetics of Char Gasification

Abstract

Based on traditional kinetic models of the gasification process of char, a new modified random pore model (MRP) was proposed. This model can be reduced to a traditional volume model (VM), an unreacted shrinking core model (URCM), a hybrid model (HM), and a random pore model (RPM) by varying the model parameters. Furthermore, not only is the relationship between the reaction rate and conversion rate well described by MRP, as it is in other models, but the position of the maximum reaction rate is also described, which is out of the application range of other traditional models. MRP was validated by gasification of different kinds of chars under different experimental conditions, such as in a carbon dioxide atmosphere, in the presence of water vapor, or with the addition of catalyst. The char gasification process under various conditions could be simulated by MRP with better fitting results than the traditional RPM.

Keywords

• Modified random pore model
• Char
• Gasification