GASIFICATION CHARACTERISTICS OF COAL IN A MOVING-BED PRESSURE GASIFIER

Gasification of six Indian coals was carried out in a moving bed pressure gasification pilot plant in oxygen-blown mode. The effect of operating pressure on the gasification characteristics such as raw gas yield as well as methane yield from 1000 kg coal on dry ash free basis (d.a.f.), oxygen consumption for the gasification of 1000 kg coal (d.a.f.) and the requirement of coal (d.a.f.) for the production of 1000 Nm(3) CO-H-2 mixture were examined. Combining the present data for Indian coals with published data for lignite and coals from other countries, correlations between the rank of coal and its gasification characteristics are proposed. From a detailed error analysis, it has been possible to conclude that the gasification characteristics of coals of a wide ranging rank expressed as carbon ratio or coalification index can be predicted by these correlations with reasonable accuracy. It is further concluded that predictions based on carbon ratio are more accurate.