Abundant low cost low rank coal may now be gasified by partial oxidation or burned in a furnace or boiler. About 30 to 45 parts by wt. of comminuted low rank coal is mixed and reacted in the reaction zone of a partial oxidation gas generator with a free-oxygen containing gas and (a) about 1 to 3 parts by wt. of a residual fuel oil, and (b) about 70 to 55 parts by wt. of water. The hot effluent stream of synthesis gas, reducing gas or fuel gas from the partial oxidation gasifier may be purified to provide a gas stream which will not pollute the environment.