由于加工中东混合原油，造成某公司0.5 Mt/a催化裂化装置原料盐含量高达23.35~100 mg/L，表现为平衡催化剂活性低，产品分布差，分馏系统结盐严重，汽、柴油分离精度差。通过增设电脱盐系统，优化操作参数和选择合适的破乳剂，催化料平均含盐量由53.7 mg/L降低至2.67 mg/L，脱盐率大于95%；平衡催化剂活性提高5%，催化剂单耗降低38.6%；产品分布改善，干气和焦炭产率降低23.7%，降低了富气压机和主风机负荷；汽油收率增加5.4%，经济效益显著；同时，分馏系统结盐现象得到改善，产品分离精度显著提高。

Shandong Haiyou Petrochemical Group has been processing Middle East mixed crude oil in recent years,resulting in that the salt content in the feedstocks of 0.5 million t/a FCC unit reaches as high as 23.5-100 mg·L^-1,causing a low equilibrium catalyst activity,poor products distribution,serious salt deposition in the fractionation systems and poor separation accuracy between gasoline and diesel.By setting up an electric desalination system,optimizing the operating parameters and selecting the appropriate demulsifier,the average salt content in FCC feedstocks drops from 53.7 mg·L^-1 to 2.67 mg·L^-1,representing a desalination rate of more than 95%.The activity of equilibrium catalyst is raised by 5% and the unit consumption of catalyst is decreased by 38.6 wt%.Products distribution has also been improved,total yields of dry gas and coke falls by 23.7 wt%,the loads of main air blower and rich gas compressor are reduced.Gasoline yield is increases by 5.4 wt%,and the economic benefits improves significantly.At the same time,salt deposition phenomenon in the fractionation systems is improved and the separation accuracy is remarkably promoted.