Modeling of particle size distribution of limestone in sulfur capture in air and oxy-fuel circulating fluidized bed combustion

Abstract

Measurements for partition of Ca-containing compounds in particles in air and oxy-fuel combustion are presented. A model for steady and unsteady state particle size distribution (PSD) of limestone including the effects of PSD of the feed, attrition, fly ash, and bottom ash removal is presented. By incorporating models for sulfation, a new model for distribution of Ca-containing compounds CaCO 3 , CaO, and CaSO 4 in different particle sizes during sulfation is found. The model can be applied to study the effects of different factors on the PSD of limestone in the bed, to optimize the PSD in the bed, and to study reasons for the measured PSDs and distributions of Ca-containing compounds in different size fractions in the bed in sulfur capture in circulating fluidized bed combustion in air and oxy-fuel conditions.