METHOD FOR TREATING EFFLUENT GAS FROM SULFONATION PROCESS

摘要

A relatively large amount of S02 effluent gas from a sulfonation process is converted to S03 and recycled back to the sulfonation process as part of the S03 sulfonating agent. The rest of the S03 used as the sulfonating agent is derived from a sulfur burner located downstream of the sulfonation operation and in the recycle path of the S02 in the effluent gas. Hydrocarbons in the effluent gas are converted to C02 and H20 in the sulfur burner. The H20 and S03 are removed from the gas stream at an S03 absorber which forms rich oleum from which the S03 is subsequently removed for use in the sulfonation operation, leaving lean oleum which is used at the S03 absorber to remove H20 and S03 from the gas stream. Gases leaving the S03 absorber include some S03 and are passed through an H2S04 absorber along with water and lean oleum to produce concentrated H2S04.