EG聚醚与助剂复配破乳剂的破乳性能

张瑾 张谋真 刘丽 刘启瑞 席凡 付豪杰 李七一 权乐乐 杜科科

摘 要：为解决陕北原油采出液现用破乳剂用量大、脱水率低、污水含油和悬浮物多、中间层厚的问题，用聚醚EG与多种助剂复配，对陕北子长和河庄坪原油进行脱水试验，并测定净化油的含盐量、含水量及污水含油量。实验结果表明：对子长原油，破乳剂总用量200 mg·L-1，脱水温度65 ℃，脱水时间6 h时，EG与R18CJL复配脱水率最高，达到98.3%，净化油含盐量0.280 7 mg·L-1，净化油含水量0.00 mg·L-1，污水含油量339.3 mg·L-1；对河庄坪原油，EG单剂用量为100 mg·L-1，脱水温度55 ℃，脱水时间6 h时，脱水率达98.7%，净化油含盐量0.267 4 mg·L-1，净化油含水量0.00 mg·L-1，污水含油量28.0 mg·L-1。且两种原油脱水后均悬浮物少，界面齐。

关 键 词：原油；复配破乳剂；助剂；陕北油田

中图分类号：O 647 文献标识码：A 文章编号： 1671-0460（2016）04-0665-03

Abstract： Several new combinational demulsifiers combining polyether EG with various additives are used to solve the problems that demulsifier use level is high， dehydration rate is low， the content of oil and suspended matter is large in sewage and middle oil-water emultion layer is thick for the existing demulsifiers for produced liquid of North Shaanxi oil fields. Dehydration experiments of the combinational demulsifiers were conducted at 55 ℃ in 6 h and demulsifier concentration was 100 mg·L-1 for Hezhuangping crude oil， and demulsifier concentration was 200 mg·L-1 at 65 ℃ in 6 h for Zichang crude oil in North Shaanxi by bottle test， salt and water content in purified oil and oil content in sewage were measured at same time. As a result， for Zichang crude oil， the dehydration rate of combinational demulsifiers is 98.3%， salt content in purified oil is 0.280 7 mg·L-1， water content in purified oil is 0.00 mg·L-1 and oil content in sewage is 339.3 mg·L-1 when using EG combined with R18CJL； and for Hezhuangping crude oil， the dehydration rate of combinational demulsifiers is 98.7% when only using EG. There is 0.264 7 mg·L-1 salt content in purified oil， 0.00 mg·L-1 water content in purified oil， 28.0 mg·L-1 oil content in sewage. And there is no suspended matter； interface between water-oil is homogeneous for the two kinds of crude oil.

Key words： Crude oils； Combinational demulsification； Additive； North Shaanxi oil field

原油开采时，原油与地下水同时采出，油水流经岩层孔隙、管道时，因搅动混合作用，形成稳定的油水乳状液。原油中的水会增加输油设备的负荷，引起管线的腐蚀和结垢。因此脱水是原油生产必不可少的环节，常用的脱水方法为化学破乳法，即添加破乳剂来破坏原来的乳化状态，使油水分离[1-3]。

原油乳状液通常以油包水乳状液的形式存在。原油中的天然乳化剂（如胶质、沥青质、蜡等）可以吸附到油水界面，在油水界面形成界面膜，导致原油乳状液稳定性提高。化学破乳法是用破乳剂取代天然乳化剂。加入破乳剂可以改变油水界面的界面性质，如降低界面张力、机械强度、界面膜弹性及厚度，加速水滴的絮凝和聚结[4，5]。此外，复配破乳剂中的聚醚和乳状液水滴中的金属离子能形成配合物来减少水滴表面所带负电荷，降低水滴间的静电斥力，从而促进水滴聚结[6]。……