Desulphurization of Coal to Protect the Environment

Abstract

The major coal desulphurization technologies prior to combustion are physical coal cleaning, chemical and biological methods. Each has some technical and economical limitations. Physical coal cleaning can only remove limited amount of inorganic sulphur due to insufficient liberation. Fine grinding can liberate fine pyrites, where novel coal cleaning techniques are required for separation. Advanced froth flotation, oil agglomeration, selective flocculation and heavy media cycloning are the novel cleaning techniques, most of which have been, or nearly being, commercially deployed. Chemical cleaning techniques, due to their high processing costs, and bicrobiological desulphurization, with its technical and economical uncertainties, are not already commercially applied. Preliminary cost estimations have shown that pre-combustion desulphurization techniques might be competitive with the current post-combustion technologies.