Hydroliquefaction of sub-bituminous and lignitic coals to heavy pitch

摘要

In the hydroliquefaction of a sub-bituminous and/or lignitic coal, the inlet temperature to the hydroliquefaction zone is maintained at a temperature higher than those previously employed by providing recycle of hot liquid from the outlet portion of the hydroliquefaction zone. In this manner, the hydroliquefaction is operated at higher average temperatures, and total reaction volume is reduced, thereby reducing overall costs.