针对炼厂回炼清罐油时常见电脱盐罐电流波动的问题,对清罐油预处理、一级电脱盐罐运行状况实地考察并进行了优化调整。结果表明,阻止原油形成稳定的乳状液是核心问题,在清罐油净化过程中不加聚合氯化铝和聚丙烯酰胺这类絮凝剂,避免与原油形成稳定乳状液;控制脱前原油铁含量在0~5 mg/kg,抑制铁离子增加原油乳状液的稳定性和电导率;提前将破乳剂的注入量提至10~15 g/t;日检电脱盐罐乳化层情况并及时排尽。通过以上措施,常减压装置持续回炼清灌油139 d,一级电脱盐罐电流未出现波动,含盐污水环保排放指标合格。

Electric current fluctuation often occurs at the electric desalting tank in a refinery when the tank-cleaning oil is blended with crude oil as feedings.In order to solve this problem,the pretreatment of tank-leaning oil and the operation status of primary electric desalting tank are investigated on the spot and optimized.It is indicated that preventing crude oil from forming a stable emulsion is the core solution.Therefore,some measurements are taken as follows.Flocculants such as polyaluminum chloride and polyacrylamide are not added again in the purification process of tank-cleaning oil to prevent them from forming more stable emulsion with crude oil.The iron content of crude oil before stripping is controlled in the range of 0 to 5 mg·kg^-1 to prevent iron ions from increasing the stability and conductivity of crude oil emulsion.The injection amount of demulsifier is controlled in the range of 10-15 g·t^-1 in advance.The emulsification layer at the electric desalting tank is drained on time.Through implementing these measures,the atmospheric-vacuum distillation unit has refined continuously tank-cleaning oil for 139 days while the electric current at the primary electric desalination tank has remains stably,and the discharge index of salt-containing sewage meets the standard.

李治明(1993-),男,硕士,工程师,从事炼油化工工作,1130093363@qq.com;秦梓喻(1991-),男,博士,讲师,研究方向为精细化工、石油化工,通讯联系人,ziyuqin@hainanu.edu.cn。