Gasification of six Indian coals was carried out in a moving bed press
ure gasification pilot plant in oxygen-blown mode. The effect of opera
ting pressure on the gasification characteristics such as raw gas yiel
d 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 characteris
tics are proposed. From a detailed error analysis, it has been possibl
e 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 furthe
r concluded that predictions based on carbon ratio are more accurate.