Coal and Coal Products: Analytical Characterization Techniques

Abstract

Mechanisms of carbonization of fluid systems from pitches and coals of different origin and rank to form anisotropic cokes are discussed. The concept of nematic liquid crystals and mesophase is introduced. The origins of optical texture in cokes and the chemical and physical factors which control the size and shape of optical texture are explained. The significance of optical texture in metallurgical cokes is analysed in terms of coke strength and chemical reactivity. Laboratory experimental approaches include control over carbonization procedures, the examination of polished surfaces of resultant cokes by optical microscopy, the use of scanning electron microscopy to monitor changes induced by thermal treatment and gasification of cokes, as well as point-counting of optical texture and the use of microstrength testing procedures. Modern technological approaches to the successful use of coals of several ranks to make metallurgical coke include blending of coals sometimes with pitch additions. The resultant enhancement