Modelling the fuel reactor of a fluidised bed chemical-looping coal combustor

Abstract

Chemical-looping combustion (CLC) of coal has emerged as a clean coal technology that can potentially be applied for the efficient combustion of coal while producing flue gas that has a CO2 concentration of greater than 99 %. An important component of a CLC combustor is the fuel reactor (FR) where conversion of the coal takes place. A bubbling fluidised bed reactor model originally developed at the CSIR to simulate the gasification of high-ash coal was modified so that it can be used to simulate the FR of a chemical-looping combustor. Simulations were carried out to investigate the effect of coal, oxygen carrier and operating variables on the performance of the FR. Simulations predict that the temperature, pressure, oxygen carrier reactivity, coal reactivity and coal residence time has the greatest effect on the coal conversion efficiency in the fuel reactor.