Kinetic Models for Coal Hydrogasification and Analyses of Hydrogasification Characteristics in Entrained-Flow Gasifiers

Coal hydrogasification (CHG) is a promising technology for clean and efficient coal utilization. However, the kinetic mechanism of CHG has not been fully understood, and multidimensional numerical simulations of CHG in entrained-flow gasifiers are still rarely reported. To evaluate and optimize hydrogasification parameters in an entrained-flow-bed gasifier, it is necessary to develop a reasonable CHG kinetic model and carry out the corresponding numerical simulations. In this work, a CHG kinetic model, including five homogeneous reactions and three heterogeneous reactions, is established. Thereinto, for the heterogeneous reactions, a novel combined random pore and shrinking-core model with pressure correction (CRPSC–PC) is put forward to predict the char–gas reaction process. When the CHG model is set up, it is then loaded to the commercial computational fluid dynamics (CFD) package, Fluent, via the user-defined function (UDF), and the simulation results are validated against literature-available experime...

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