LP油田沉降罐过渡带原油破乳脱水实验研究

Experimental study on demulsification and dehydration of crude oil in the transition zone of LP oilfield sedimentation tank

LP油田沉降罐过渡带原油中含有起乳化作用的胶态FeS等成分,导致原油脱水困难,不能满足原油进后续电脱水器的要求;分析了过渡带原油物性、原油组分及采出水组成,对FeS脱除剂及破乳剂的筛选进行优化实验,重点研究了FeS脱除剂与破乳剂联合破乳效果及适应性。结果表明,筛选出的FeS脱除剂BLJ-01对FeS有很好的溶解效果,体积分数3%的FeS脱除剂BLJ-01和质量浓度800 mg/L的破乳剂X-75联合使用,55℃下可有效去除沉降罐过渡带原油中FeS,沉降罐过渡带原油脱水率达85.78%;BLJ-01与X-75配合使用适应性较强,对含水率超过40%的P2联合站沉降罐过渡带原油脱水率均可达80%以上,且在弱酸或弱碱性条件下都可以表现出优良的破乳效果,也适用于SJ站沉降罐过渡带原油的破乳脱水,并能显著降低破乳剂使用量。

The crude oil in the transition zone of LP oilfield settlement tank contains colloidal FeS and other components that play an emulsifying role,which makes crude oil dehydration difficult and cannot meet the requirements of crude oil inlet electrodehydrator.The physical properties,crude oil composition and produced water composition of crude oil in the transition zone were analyzed,and the screening of FeS remover and demulsifier was optimized,and the demulsification effect and adaptability of the combined FeS remover and demulsifier were studied.The results show that the screened FeS remover BLJ-01 has a good dissolution effect on FeS,and the combination of 3%FeS remover BLJ-01 and 800 mg/L demulsifier X-75 can effectively remove FeS from crude oil in the sedimentation tank transition zone at 55℃,with the dehydration rate of crude oil in the sedimentation tank transition zone reachings 85.78%.BLJ-01 has strong adaptability with X-75,and the dehydration rate of crude oil in the transition zone of P2 joint station settlement tank with a water content of more than 40%can reach more than 80%.It can show excellent demulsification effect under weak acid or weak alkaline conditions,which is also suitable for demulsification and dehydration of crude oil in the transition zone of SJ station settlement tank,and can significantly reduce the amount of demulsifier.