高效驱油用表面活性剂室内实验研究

Laboratory Study for Surfactant Used for Efficient Flooding

通过单因素实验,得到重烷基苯磺酸钠(A1)、异丙醇(CH-2)、异构十醇聚氧乙烯醚(F-2)、Gemini表面活性剂(GL-2)的最佳质量比为3:6:2:2的表面活性剂体系CQBH-1,并进行了配伍性、吸附性和驱替实验。CQBH-1的价格比市场销售的油田常用表面活性剂平均低20%以上。结果表明,在质量分数0.3%～0.5%下,CQBH-1溶液与长庆某油田模拟原油间的界面张力为5×10^(-3)～8×10^(-3)mN/m。在常压、60℃下,CQBH-1与该油田注入水、地层水和原油均有良好的配伍性,且具有较好的抗吸附性能,质量分数为0.3%～0.5%的CQBH-1溶液静态吸附后与模拟原油间的界面张力仍能达超低数量级。岩心驱替实验表明,注入0.3PV质量分数为0.5%的CQBH-1表面活性剂溶液,渗透率为1.1×10^(-3)～100×10^(-3)μm^2人造岩心在平均水驱采收率56.70%的基础上可平均提高采收率10.48%。

According to single factor experiments, the surfactant system CQBH-1 was obtained by compounding heavy alkyl benzene sulfonic acid sodium （A 1 ） with isopropanol （CH-2）, Isomeric alcohol ethoxylates （F-2） and gemini surfactant （GL-2） in mass ratio of 3：6：2：2, the price of which is lower than commonly used surfactants in oil field by more than 20%. The compatibility, adsorption and displacement experiments were conducted. The results showed that the interfacial tension between CQBH-1 solution with mass fraction 0.3%-0.5% and the simulated crude oil of Changqing oilfield was 5 × 10-3-8× 10-3 mN/m. CQBH-1 had good compatibility with Changqing oilfield injected water, formation water and simulation crude oil in normal pressure and at the temperature of 60℃, and had good resistance to adsorption. After static adsorption, the interfacial tension between CQBH-1 solution with mass fraction of 0.3%- 0.5% and the simulated oil could reach super-low interfacial tension. Core displacement experiments showed that on the basis of water flooding of average oil recovery of 56.70%, the oil recovery of the artificial cores with permeability of 1.1 × 10-3--100×10-3 μm2 could be enhanced by 10.48% through injecting 0.3 PV of CQBH-I surfactant solutions.