Two=stage pyrolysis of coal - using by=produced coke as heat carrier and for water gas generation

摘要

Prodn. of gaseous and liq. products from particulate coal (or other solid fuel) is carried out by drying followed by 2-stage pyrolysis. Part of the particulate coke formed during pyrolysis is recycled as heat carrier to the drying unit, the rest is heated to 800-1500 deg.C by contact with hot gas and/or by partial combustion. The heated coke is then sepd. from gases and gasified with steam from the drying unit. The resulting water gas is sepd. from the residual coke, which is recycled as heat carrier to the 1st. stage pyrolysis reactor. The process has a high energy efficiency (84-88%) and gives high prod. yields without pollutant emission and without formation of slag deposits in the system.