SOOT IN COAL COMBUSTION SYSTEMS

Soot is generated from coal when volatile matter, tar in particular, u ndergoes secondary reactions at high temperatures. A description of so ot in coal flames allows better calculations of radiative transfer and temperatures in near-burner regions, which in turn allows more accura te predictions of NOx formation in coal-fired furnaces. Experiments ar e reviewed that examine the formation, agglomeration and properties of coal-derived soot, including pyrolysis experiments and combustion exp eriments. This review includes the types of experiments performed, the soot yields obtained, the size of the soot particles and agglomerates , the optical properties of soot, the relationship between coal-derive d soot and soot from simple hydrocarbons, and attempts to model soot i n coal flames. (C) 1997 Elsevier Science Ltd.