聚合物-表面活性剂二元抗盐体系注入性能评价

Evaluation and Study of Injection Performance of Binary System of Anti-Salt Polymer and Surfactant

针对M油田目的层油藏物性差、非均质强、矿化度高等问题,研究了新型双烷基甘油醚衍生表面活性剂(diGE-EO)的耐温抗盐性能,并利用霍尔曲线对比研究了聚合物和聚合物-表面活性剂二元抗盐体系的注入性能,分析了聚合物-表面活性剂二元抗盐体系提高M油田目的层原油采收率的可行性。研究结果表明:双烷基甘油醚衍生表面活性剂(diGE-EO)在质量浓度高于3500 mg/L时依然保持较好的抗盐性能,在85℃条件下放置超过45 d,仍能使油水界面张力降至5.73×10^(-3)mN/m,处于超低界面张力范围,可满足高矿化度油藏开发的要求。同时分析了聚合物-表面活性剂二元抗盐体系的注入性能。结果表明,当聚合物溶液质量浓度达到1500 mg/L、岩心渗透率低于200 mD时,单独注入聚合物难度增大;存在表面活性剂情况下,注入性能得到明显改善。该结果为M油田二元复合驱项目方案设计及现场实施提供了室内实验基础。

To address the problems of poor physical properties,high heterogeneity and high salinity of the target reservoir in M Oilfield,the temperature and salt resistance of a new dialkyl glycerol ether-derived surfactant(diGE-EO)was studied in this paper,the injection performance was compared with Hall curve between the polymer and the polymer-surfactant binary salt resistance system,and the feasibility of polymer-surfactant binary displacement system to enhance oil recovery in the target reservoir of Minsk Oilfield was analyzed.The study results show that The diGE-EO can maintain high salt resistance at concentrations higher than 3500 mg/L,and can reduce the oil-water interfacial tension to 5.73×10^(-3) mN/m after being placed at 85℃for more than 45 days,which is in the ultra-low interfacial tension range,meeting the requirements for the development of highly mineralized reservoirs.The injection performance of polymer-surfactant binary anti-salt system is also analyzed.The results show that when the mass concentration of polymer solution is up to 1500 mg/L and the core permeability is lower than 200 mD,and it becomes more difficult to inject polymer alone;in the presence of surfactant,the injection performance is significantly improved.The test results provide a laboratory test basis for the scheme design and field implementation of binary composite flooding project in M oilfield.