摘要
针对渤海稠油油藏原油黏度高、胶质沥青质含量高、易在井筒和筛管处形成有机垢堵塞渗流通道降低油井产量的问题,筛选研制了适宜的洗井液体系,并对洗井液的性能进行了评价。稠油油藏洗井液由溶剂油ZC-RJ2、表面活性剂ZC-BH、降黏剂ZC-JN和互溶剂ZC-HR组成,洗井液溶解沥青速率为2.56 mg/(mL·min),溶解石蜡速率为3.78 mg/(mL·min)。洗井液加量为3.0%时,体系对原油的降黏率为99.28%,此时原油乳化分散成3~5μm的小微粒。洗井液加量为1.0%时,体系界面张力为31.03 mN/m,进一步增加洗井液浓度,界面张力基本不变。洗井液加量为3.0%时原油清洗效率为99.87%,岩心渗透率恢复值为96.82%。洗井液在渤海某油田修井过程中现场应用10井次,修井后单井平均产液量提升1.6倍,较地热水洗井后产液量增加45.5%,现场应用效果显著。
Aiming at the problem of high viscosity of crude oil and high content of colloidal asphaltene in Bohai Heavy Oil Reservoir,it is easy to form an organic scale and plug seepage channel at the wellbore and screen to reduce the production of oil wells. A set of washing fluid system suitable for heavy oil reservoirs has been screened. The heavy oil reservoir washing fluid consists of solvent oil ZC-RJ2,surfactant ZC-BH, viscosity reducer ZC-JN and mutual solvent ZC-HR according to a certain proportion. The performance of the well washing fluid was studied by asphaltene dissolution rate meter,interfacial tension meter,electron microscope and core flow tester. The results show that the rate of dissolved bitumen in the well fluid was 2. 56 mg /( mL. min) and the rate of dissolved paraffin was 3. 78 mg /( mL. min). When the amount of washing fluid is 0. 3%,the system to the viscosity reduction rate of the crude oil is 99. 28%. At this time,the crude oil is emulsified and dispersed into small particles of 3 ~ 5 μm. When the amount of washing fluid is 1. 0%, the interfacial tension of the system is 31. 03 mN/m,and the interfacial tension of the washing fluid concentration is further increased. When the amount of washing fluid is 3. 0%,the cleaning efficiency of crude oil is 99. 87%,and the recovery value of core permeability is 96. 82%. The well washing fluid was applied to the well in Bohai Oilfield during workover process. After the operation,the average liquid production per well increased by 1. 6 times,and the liquid production increased by 45. 5% compared with the geothermal water washing. The field application effect was remarkable.
作者
邢希金
曹砚锋
郭宏峰
刘磊
刘文辉
张博
孙广杰
徐丽媛
XING Xijin;CAO Yanfeng;GUO Hongfeng;LIU Lei;LIU Wenhui;ZHANG Bo;SUN Guangjie;XU Liyuan(CNOOC Research Institute,Beijing 100027;China Oilfield Services Ltd.,Tianjin 300459)
出处
《精细石油化工进展》
CAS
2019年第1期5-9,共5页
Advances in Fine Petrochemicals
基金
国家科技重大专项"海上稠油油田高效开发钻采技术"(2015ZX05025-002)
关键词
稠油油藏
洗井液
洗油率
降黏率
现场应用
heavy oil reservoir
well washing fluid
oil displacement rate
viscosity reduction rate
field application