长庆C致密油层采出水水质改性处理小型试验  

Small Scale Test of Water Quality Modification Treatment for Produced Water in Changqing C Tight Reservoir

作　　者：单巧利 张帆 张巧生 王通 SHAN Qiaoli;ZHANG Fan;ZHANG Qiaosheng;WANG Tong(National Engineering Laboratory for Exploration and Development of Low Permeability Oil and gas Fields·Xi'an Changqing Technology Engineering Co.,Ltd.)

机构地区：[1]低渗透油气田勘探开发国家工程实验室·西安长庆科技工程有限责任公司

出　　处：《油气田地面工程》2021年第1期46-51,共6页Oil-Gas Field Surface Engineering

摘　　要：长庆致密油层逐渐实现规模开发,受开发特点限制,仅少量采出水用于注水吞吐,其他富余采出水需回注其他地层。不同层系之间采出水多存在不同程度的结垢情况,因此致密油层采出水需经过改性处理后方可安全有效回注。选择该区域侏罗系作为目的回注层,开展致密油层采出水物性分析及水质改性小试试验。经小试试验验证,采用“化学沉淀法+二级过滤+离子交换法”工艺,采出水中的钙、镁、锶成垢阳离子得到了有效去除。通过Scalechem软件模拟,改性后采出水与侏罗系采出水混合比例为6∶4时,模拟结垢量降至146 mg/L,为改性前最大结垢量617 mg/L的28.5%;悬浮物、含油浓度分别由来水的78 mg/L、45 mg/L降至1 mg/L以下,水质改性工艺有效。The scale development of Changqing tight reservoir is gradually realized.Restricted by its development characteristics,only a small amount of produced water is used for waterflood stimulation,and other surplus produced water needs to be injected back into other formations.There are different degrees of scale formation in produced water of different layers,so the produced water of tight reservoirs should be modified before a safe and effective reinjection.In the experiment,the Jurassic system is selected as the target reinjection layer to carry out physical characteristics analysis and water quality modification test of the produced water in tight reservoir.Through small scale tests,it is verified that the process of"chemical precipitation+two-stage filtration+ion exchange"is used and the positive ions like calcium,magnesium,and strontium are effectively removed.By simulation of Scalechem software,when the mixture ratio of produced water and Jurassic produced water after modification is 6:4,the simulated scaling volume is reduced to 146 mg/L,which is 28.5%of the maximum scaling volume of 617 mg/L before modification.The concentration of suspended solids(78 mg/L)and oil(45 mg/L)from water are reduced to be less than 1 mg/L,and the water quality modification process is effective.

关 键 词：采出水 致密油层 侏罗系层 水质改性 小试试验 

分 类 号：X741[环境科学与工程—环境工程]