Compared with the direct injection of dilution steam into traditional naphtha cracker, the ethane cracker controls the required dilution ratio by controlling the humidification or saturation of ethane in ethane saturator. The long-term operation of ethane saturator has become a key control point for the long-term operation of ethylene plant. This article explains that the long-term operation of ethane saturator can be ensured by controlling the oil content, COD, pH, iron ion concentration, conductivity and blowdown flow rate of the circulation process water of ethane saturator, continuously monitoring the pressure difference of packing in ethane saturator, and regularly switching the circulation pumps of ethane saturator.