致密气层控水压裂用纳米乳液的制备及性能评价

发布时间：2018-06-26 09:21

本文选题：正交设计 + 氨基聚硅氧烷　；参考：《中国石油大学学报(自然科学版)》2016年01期

【摘要】：以氨基聚硅氧烷与绿色表面活性剂脂肪酸甲酯磺酸钠(MES)为主要原料,应用正交设计实验优化得到致密气井压裂控水用纳米乳液形成的最佳条件。分析纳米乳液中液滴尺寸分布与致密岩心孔喉的匹配性,考察纳米液滴吸附后对致密岩心表面微观结构与界面性质的影响,评价纳米乳液的耐冲刷与控水性能。结果表明:为形成良好的纳米乳液,应调节氨基聚硅氧烷与水质量比为1∶2,乳化剂MES、正丁醇、氯化钾加量分别为氨基聚硅氧烷质量的40.0%、20.0%、5.0%,乙酸调节p H至6.5;纳米乳液中液滴中值粒径平均为28.5 nm,与致密岩心孔喉尺度匹配良好;随着纳米乳液质量分数的增加,岩心孔隙表面从尖锐的沟槽形貌逐渐转变为均匀、平滑的峰谷结构,润湿性也呈现强疏水性质;纳米乳液耐冲刷性能良好,0.5%的纳米乳液能降低水相相对渗透率超过60%,而对气相渗透率影响较小,说明纳米液滴借助氨基、硅氧键与硅氢键等极性基团通过物理化学吸附作用牢固附着在岩石表面,而分子链中疏水基团硅甲基改变了岩石表面润湿性质,对气/水在致密孔隙裂缝中的渗流产生了较大影响。
[Abstract]:Using amino polysiloxane and green surfactant sodium fatty acid methyl ester sulfonate (mes) as the main raw materials, the optimum conditions for the formation of nano-emulsion for fracturing and controlling water in dense gas wells were obtained by orthogonal design. The matching properties of droplet size distribution and pore throat of dense core in nano-emulsion were analyzed. The effects of nano-droplet adsorption on microstructure and interfacial properties of dense core surface were investigated, and the scour resistance and water control performance of nano-emulsion were evaluated. The results showed that in order to form a good nanometer emulsion, the mass ratio of amino polysiloxane to water should be adjusted to 1: 2, and the emulsifier MES, n-butanol should be adjusted. The amount of potassium chloride is 40.0% of the mass of amino polysiloxane, and acetic acid adjusts pH to 6.5. The mean diameter of liquid droplet in nano-emulsion is 28.5 nm, which matches well with the scale of tight core pore throat, and with the increase of mass fraction of nano-emulsion, The pore surface of the core gradually changed from the sharp groove morphology to a uniform, smooth peak-valley structure, and the wettability also showed a strong hydrophobic property. The nanometer emulsion with good scour resistance (0.5%) can reduce the relative permeability of water phase by more than 60%, but has little effect on the gas phase permeability. The polar groups such as Si-O bond and Si-H-bond are firmly attached to the rock surface through physicochemical adsorption, while the hydrophobic group silicomethyl group in the molecular chain changes the wetting property of the rock surface. It has great influence on the seepage of gas / water in tight pore fracture.
【作者单位】：中国石油大学石油工程学院;
【基金】：山东省优秀中青年科学家科研奖励基金项目(BS2012HZ029) 山东省自然科学基金项目(ZR2012EEM001)
【分类号】：TE377

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