三元复合驱体系各组分静态吸附规律

当三元复合驱体系各组分流经地下多孔性油藏时,与岩石基质长时间作用会引起各组分吸附损失,甚至使各组分脱离最佳配比,影响驱油效率。为了尽量减少吸附损失,提高驱油效率,研究了一元、二元、三元体系中各组分在苏丹油田油砂上的吸附量,比较了同一化学剂在不同体系中吸附量的差别,并分析了各组分间相互作用对吸附量的影响。结果表明:对于一元体系,石油磺酸盐和碳酸钠在砂粒表面的最大吸附量分别为4.82和1.50 mg/g;而在石油磺酸盐质量分数为0.1%的表面活性剂—聚合物二元体系中,石油磺酸盐在砂粒表面的吸附量降至3.55 mg/g;在三元体系中,碳酸钠在砂粒表面的吸附量增至1.70 mg/g,且当碱的质量分数超过1.0%后,表面活性剂和聚合物的吸附量均持续上升。在各组分之间的综合作用中,当碱的质量分数小于1.0%时,聚合物降低扩散速率居于主导地位,而大于1.0%后,聚合物的水解作用占主导地位。

Study on static adsorption of each components during the process of ASP flooding

During the flow of combined chemical flooding solution through porous media, the adsorption occurs for each component due to the long time contact with reservoir matrix. The optimized ratio of components may be changed and oil-displacing efficiency will be affected subsequently. The adsorption of each component in the unary, binary, and ternary formulations is evaluated. The interaction among the components of chemical flooding formulations is analyzed. The results show that, for the unary formulation, the maximum adsorptions of alkali and surfactant are 1.51 mg/g and 4.82 mg/g, respectively. For the petroleum sulfonate/polymer binary formulation,the adsorption of surfactant decreases to 3.55 mg/g. For the ASP formulation, the adsorption of alkali is increased to 1.70 mg/g and the adsorption of the surfactant and polymer keeps rising when the alkali concentration is higher than 1.0%. It can be seen from the interactions that, the polymer plays the dominant role which can reduce the diffusion rate when the alkali concentration is lower than 1%. Hydrolysis of the polymer plays the dominant role when the alkali concentration is higher than 1%.