超低界面张力石油磺酸盐复配驱油剂研究

摘要

Effects of mass fraction of Xinjiang petroleum sulfonate ( XPS) solution and salinity on the interfacial tension between XPS solution and Daqing ( Area L) crude oil were studied through laboratory experiments. Meanwhile, in order to replace the alkali composed in ASP oil displacement agent, different kinds of surfactant were blended with the XPS mentioned above, and the optimal synergistic combination which can effectively reduce oil - water interfacial tension to ultra - low value (10-3 mN/m order of magnitude) was screened out. Experimental results showed that, under the condition that salinity lies between 6 000 ~ 10 000 mg/L and the content of calcium and magnesium ion is lower than 20 mg/L, the XPS has good resistance to salinity,and can reduce the oil - water interfacial tension to ultra - low value. Among different kinds of surfactant applied in the experiment, betaine surfactant shows remarkable synergistic effect in the blended XPS. Especially, cocamidopropylsulfobetaine (ASB) shows particular excellent synergistic effect with wide concentration range and easier to reduce the oil - water interfacial tension to ultra - low value.%通过室内实验研究了溶液质量分数、矿化度对石油磺酸盐溶液与大庆L区块原油的界面张力的影响,并将不同类型表面活性剂分别与石油磺酸盐复配,筛选出能够使油/水界面张力降至超低(10-3 mN/m数量级)的最优增效组合,以取代ASP复合驱中所加的碱.实验结果表明,在矿化度为6 000～10 000 mg/L,钙、镁离子质量浓度不超过20 mg/L时,石油磺酸盐表面活性剂有良好的抗盐性,可使油/水界面张力达到超低.在实验所选的不同类型表面活性剂中,石油磺酸盐与甜菜碱型表面活性剂复配起到明显的增效作用,特别是与椰油酰丙基磺基甜菜碱复配增效作用尤为显著,且两者复配的浓度范围较宽,油/水界面张力易达到超低.