COMBUSTION OF PULVERIZED COAL WITH ADDITIVES UNDER CONDITIONS SIMULATING BLAST-FURNACE INJECTION

The combustion properties of pulverized coal with additives were studi ed under conditions simulating injection into the blast furnace (heati ng rate 10(5) K s(-1), residence time <20 ms, final temperature 1500 d egrees C). Coal rank, particle size and injection rate were varied. Th e additives were residuals from scrap automobiles (shredded light frac tions), in various proportions. The performance of the coals tested wa s very dependent on coal rank and injection rate. The degree of combus tion was generally improved with larger particle sizes at oxygen/coal ratios greater than the stoichiometric value. An increase in the amoun t of additive resulted in a lower degree of burnout. By using shredded light fractions in proportions up to 30 wt% with Lohberg coal and up to 10 wt% with N.Pedio lignite, a high level of burnout and a high inj ection rate could be achieved. Copyright (C) 1996 Elsevier Science Ltd .