80℃高温油藏聚驱后复合驱油体系性能评价

Performance Evaluaton of Polymer-Surfactant Combinational Flooding System in 80℃ High Temperature Reservoir after Polymer flooding

郭 艳[] 李树斌 韩志红 王琦 郝明耀 王纪云 张丽庆

GUO Yan LI Shu-Bin HAN Zhi-Hong WANG Qi HAO Ming-Yao WANG Ji-Yun ZHANG Li-Qing

针对聚合物驱后双河油田80℃高温油藏，从10种表面活性剂中筛选了石油磺酸盐表面活性剂1#，研究了表面活性剂浓度、聚合物浓度、矿化度、新鲜污水等因素对二元体系界面张力的影响，并对二元体系的长期热稳定性、表面活性剂的静态吸附量、注入性、段塞选择和岩心驱油实验进行评价。研究结果表明：1#表面活性剂具有很好界面活性，质量分数在0.1%～0.5%范围内均可达到10-3 mN/m数量级的超低界面张力，聚合物浓度对二元体系界面张力影响不大。二元体系具有很好的抗盐性和长期热稳定性，老化90 d后的界面张力仍能保持10-2 mN/m数量级。二元体系中表面活性剂在双河油砂上的吸附量要小于单一表面活性剂的吸附量。该二元体系具有良好的注入性。岩心驱油实验表明：低界面张力的二元体系提高采收率的幅度大，聚合物浓度1800 mg/L、表面活性剂浓度3000 mg/L的二元体系在聚驱后可提高采收率10.26%。

Aimed at the 80℃ high temperature reservoir after polymer flooding, Petroleum sulfonate 1# was chosen and used for the surfactant/polymer (SP) system. The effects of surfactant concentration, polymer concentration, salinity and fresh water on interfacial tension were studied, and then the long period heat resistance of the SP system, adsorption of surfactant on the Shuanghe oil sand, injectivity was studied and oil displacement experiments were carried out. The results showed that the surfactant 1# had a very good interfacial activity. The interfacial tension between the SP system and the crude oil could be reduced to ultra-low (10-3mN/m) when the concentrations was of 0.1%—0.5%. The polymer had little effect on it. The SP system had good salt tolerance and thermal stability, the interfacial tension could keep 10-2 mN/m after kept in 80℃ drying oven for 90 days. The surfactant adsorption of the SP system was lower than that of single surfactant on Shuanghe oil sand. The SP system had a good injectivity. The core flooding test showed that low interfacial tension system could enhance the higher oil recovery efficiency. The system composed of polymer concentration 1800 mg/L and surfactant concentration 3000mg/L could enhance the oil recovery of 10.26% after polymer flooding.