Preventing coke deposition in thermal processing of hydrocarbon(s) - by addn. of sulphur-contg. salts

摘要

Thermal processing of crude hydrocarbon mixts., e.g. heavy petroleum fractions of gas oil type, is carried out in presence of steam and an inhibitor consisting of a sulphur-contg. salt of an alkali(ne earth) metal. Used in pyrolysis to obtain olefins, thermal cracking of heavy fractions, retarded coking, etc. Carbon formation and coke deposits or the internal surfaces of the equipment, esp. on the tubes of pyrolysis furnaces, are inhibited, extending the operating period and life of the plant and maintaining the flow rate. The operating temp. can be raised, giving increase selectivity, raw materials which tend to coke, esp. raffinate naphthan, can be used and dilution of the raw material with steam reduced.