重劣质原油的电脱盐操作优化策略分析

An Analysis of Methods for Optimizing Electrical Desalting Operations for Heavy and Low-quality Crude Oil

重质、劣质原油电脱盐过程中,容易出现脱后原油含盐量高、含水量大,含盐污水带油量大等问题。胜利炼油厂4号常减压装置电脱盐系统通过提高电脱盐罐的注水量,提高各级罐的混合强度,投用三级电脱盐罐的注水回注一级罐,调低A,B罐的变压器档位等优化策略,实现了重劣质原油的深度脱盐脱水。由此提出:解决重劣质原油含盐问题的关键,是合适的注水量和混合强度、适宜的变压器档位,以及适宜的电脱盐设备;降低重劣质原油脱后带水的关键,是合适的注水量和混合强度、适宜的电脱盐设备,以及与装置原油性质相匹配的破乳剂和脱钙剂;降低含盐污水切水带油的关键,是合适的变压器档位和电脱盐罐界位,以及与装置原油性质相匹配的破乳剂、脱钙剂和适宜的注入量;原油电脱盐过程是逐级改善的过程,要合理发挥装置所有电脱盐设备的作用,实现最佳脱盐脱水目的。

The electrical desalting of heavy and low-quality crude oil is usually accompanied with some undesirable results such as high salt and water contents in desalted crude and high content of oil in salt-containing sewage.Shengli Refinery of Sinopec Qilu Company achieved deep desalting and dehydration of heavy and low-quality crude oil for the electrical desalitng systme of its No.4 atmospheric and vacuum distillation unit by raising the volume of water injected into the electrical desalting tanks,increasing mixing intensity for tanks at all stages,putting the first-stage feed water re-injection tank of the three-stage electrical desalting tanks into operation,and lowering the tap positions of the transformers of tanks A and B.Based on this result,the article concludes that the key to resolving the salt issue of heavy and low-quality crude oil is the appropriate volume of water injected,appropriate mixing intensity,proper tap position of transformers and proper electrical desalting equipment.According to this article,the key to reducing the content of water in dehydrated heavy and low-quality crude oil is the appropriate volume of water injected,proper electrical desalting equipment and the use of demulsifier and decalcifying agent matching the properties of the crude oil used in the unit.The key to reducing the oil carried in deoiled salt-containing sewage is the appropriate tap position of transformers,the appropriate oil-water contact of the electrical desalting tank,the use of proper demulsifier and decalcifying agent matching the properties of the crude oil used in the unit,and the appropriate injection volume.The electrical crude oil desalting process is a process of step-by-step improvement and all electrical desalting devices of the unit should come into play to achieve the best desalting and dehydrating effect.