Development of an Evaluational Prediction Tool for Coal Combustion Histories

Abstract

This paper describes a model called “FC-CBK” developed to represent the combustion histories of individual coal particles with a minimum amount of laboratory support. The FC-CBK model is a combination model of FLASHCHAIN model, one of the network depolymerization devolatilization models, and CBK8 model, a mechanism for char oxidation that quantitatively represents the latest stages of combustion. Each simulation represents the entire combustion history of particles injected into hot oxidizing gas, including drying, devolatilization, volatiles combustion with energy feedback to the particle, heterogeneous char ignition, thermal annealing, quasi-steady char oxidation with simultaneous reductions in particle density and size, and mineral effects during the char combustion. Whereas these mechanisms involve numerous reaction rate constants and physical properties, all the parameters in FC-CBK model may be specified from the proximate and ultimate analyses of the coals. In this paper, the outline of FC-CBK model, the result of the test predictions and the required input data are described.