Abstract: The concentration of sodium sulfide in the waste lye produced by ethylene plant was less than or equal to 1%. After removing sodium sulfide from the high-salinity water unit, it was discharged after qualified treatment in the sewage treatment plant. In 2021, due to the change of raw materials, the concentration of sulfide in the waste lye reached 2% to 3%, which exceeded the processing capacity of the high-salinity water unit and adversely affected the operation of the unit. In order to solve the problem of high concentration of sulfide in ethylene waste lye, the low temperature and low pressure catalytic oxidation desulfurization technology of Wuhan Junheng technology Co., Ltd. was adopted to pretreat sulfide in ethylene waste lye in 2022, and the sulfide concentration was reduced from 10,000～30,000 mg/l to less than 200mg/L. This has ensured the normal operation of the high-salinity water device.

Key words: ethylene waste lye, low temperature and low pressure, catalytic desulfurization