The structural and textural characteristics of limestones and the effectiveness of SO2 sorption in fluidized bed conditions

Abstract

The results of studies on the sorption properties of limestone with respect to SO 2 under fluidized bed conditions are presented. it has been confirmed that the structural and textural characteristics of limestones (which, contrary to the common belief, are shaping the course of the sulphation process rather than the cacO 3 content) have a decisive influence on the effectiveness of SO 2 capture. The impact of the porosity of limestones on the SO 2 sorption process has been shown. Limestone parameters, which should be assessed at the stage of qualification of raw material for raw material production, have also been determined. The research methods, which can be used to predict the reactivity of sorbent in industrial conditions at the stage of laboratory analysis, have been presented. Presented in this article studies on the reactivity of limestone terms of SO 2 were inspired by the problems of Polish power plants in meeting the SO 2 emission limits when using limestones as SO 2 sorbents in fluidized bed boilers and related to their low utilization and storage, and the high content of unreacted caO in the ash. the studies have been conducted for several years. in that time, been tested several hundred samples limestone of cretaceous (chalk), Jurassic, triassic, Devonian, and neogene (lacustrine chalk) age. the results of the study can contribute to the increased use of sorbent and thus increase the effi ciency of SO 2 capture in furnace conditions and, as a consequence, significantly reduce the amount of the combustion waste generated.