Experimental determination of the strength and reactivity of lumpy and briquetted chars from non-coking coals under melter-gasifier conditions

Abstract

ABSTRACTWith the advent of alternative smelting-reduction processes of ironmaking like COREX® and FINEX®, the demand for non-coking coals as a major raw material has increased. In these processes, char is formed from non-coking coals inside the melter-gasifier (MG) by pyrolysis. This char, either in lumpy or briquetted form, is the major reductant and fuel of the smelting-reduction process. Just like the coke in blast furnace, the char should also have certain chemical and mechanical properties suitable for operational requirements of the MG. However, there is a lack of systematic works related to the properties of chars from non-coking coals for ironmaking. This work aims to define a standardised testing method to determine the reactive and mechanical properties of lumpy and briquetted chars comparable to existing ISO norms. It also demonstrates the effect of different operational conditions on char properties. The testing method described in this work should be useful to the industry personnel to evaluate the quality of chars from non-coking coals for their usage in the MG.