三元复合驱原油脱水系统油水分离效果急剧恶化后的应急化学剂处理措施  

Chemical remedial procedures for ASP flooding produced fluid treatment systems undergoing abrupt performance failure

作　　者：吴迪[1] 蔡徇[1] 赵凤玲[1] 张会平[1] 龙彪[1] 智春生[1] 李颖慧[1] WU Di;CAI Xun;ZHAO Feng-ling;ZHANG Hui-ping;LONG Biao;ZHI Chun-sheng;LI Ying-hui(Daqing Oilfield Engineering Co.,Ltd.,Daqing 163712,China)

机构地区：[1]大庆油田工程有限公司,黑龙江大庆163712

出　　处：《精细与专用化学品》2018年第11期19-27,共9页Fine and Specialty Chemicals

摘　　要：针对大庆油田北三东区块石油磺酸盐表面活性剂弱碱体系三元复合驱采出液处理设施进液的性质受油井酸洗和酸化作业影响发生突变,油水分离难度大幅度上升,造成大量原油随分离采出水进入采出水处理设施,外输脱水油量大幅度下降的问题,通过对突变后采出液处理设施进液性质的研究,确定造成其油水分离特性严重恶化的主要原因为其中含有大量硫化亚铁和碱土金属碳酸盐等具有油水界面活性的纳米尺度固体颗粒,这些微粒吸附在油水界面上形成空间屏障阻碍油珠之间的聚并。通过联合投加可溶解硫化亚铁和碱土金属碳酸盐微粒的硫化物去除型水质稳定剂WS1005B、可抑制碱土金属碳酸盐微粒析出的水质稳定剂WS1003、对O/W型采出液兼有清水和破乳脱水双重作用的油水分离剂SP1013和可抑制电脱水器内油水过渡层的脱水型破乳剂SP1009,改善了三元复合驱采出液处理设施进液的油水分离特性,实现了石油磺酸盐表面活性剂弱碱体系三元复合驱采出液的有效油水分离,三相分离器和游离水脱除器放水含油量低于800mg/L,电脱水器出油水含量低于0.5%,分离采出水含油量低于350mg/L。After re-start of several production wells undergoing reservoir acidification and acid tubing scale removal operations,there was an abrupt downgrade of the oil/water separation performances of the produced fluid entering the surface production facilities handling the produced fluid of an ASP（Na2 CO3,petroleum sulfonate surfactant and polyacrylamide）flooding project implemented at the N3 Eblock of the Daqing Oilfield,resulting in excessive oil carry-over in produced water and drastic reduction of crude oil export.To bring the performances of the produced fluid treatment system back to its normal status,the phase separation behaviors,composition and microscopic structures of the ASP flooding produced fluid exhibiting drastic downgrade of oil/water separation performances were evaluated and analyzed.The root cause of the drastic change of the phase separation behaviors of the ASP flooding produced fluid after re-start of production wells undergoing reservoir acidification and acid tubing scale removal operations was identified as the precipitation of numerous nano-size amorphous iron sulfide and carbonate particles in the produced fluid,which exhibited strong tendencies of adsorbing on the oil/water interface and thus exerting steric hindrance to the coalescence of oil droplets.Based on the above findings,a compound sulfide scavenger and chelatant WS1005 Bwith strong iron sulfide and alkaline earth metal carbonate dissolution capacity,a chelatant WS1003 with strong depressing capacity on the precipitation of alkaline earth metal carbonate,a dual functional reverse demulsifier and demulsifier SP1013 for high water-cut crude oil emulsion,and a demulsifier SP1009 with strong depressing capacity on the pad layer in electrostatic dehydrators were selected and applied in the treatment of the ASP flooding produced fluid exhibiting abrupt downgrade of oil/water separation performances.After application of the 4 chemicals,the oil/water separation behaviors of the ASP flooding produced fluid entering the surface productio

关 键 词：三元复合驱 采出液 脱水 硫化亚铁 碳酸盐 破乳剂 水质稳定剂 硫化物去除剂 

分 类 号：TE39[石油与天然气工程—油气田开发工程]