Applications for coal-use residues: an international overview

Abstract The utilisation of coal produces large quantities of residues. Worldwide production of coal-ash is estimated to exceed 550 Mt/y. In addition to fly ash and bottom ash from pulverised coal combustion, that comprise the bulk of these residues, there are now a whole range of by-products produced by the many technologies developed for flue gas desulphurisation (FGD). Alternative methods of utilising coal, for example in fluidised bed combustion (FBC) and integrated gasification combined cycle (IGCC) systems, produce residues with other, distinctive, properties. Many utilisation options have been demonstrated for coal-use residues, including applications in building materials, for civil engineering uses, in industrial materials and in agriculture. Various commercial applications are well documented and have been carried out for many years. Research into new applications for residues is in progress at many countries around the world. Applications range from high-volume uses that require minimal processing, to low-volume, but highly specialised applications.