低渗透油藏网状胶束体系降压增注试验研究

Experimental Study of Depressurization and Augmented Injection by Mesh Micellar System for Low Permeability Reservoir

针对低渗透储层基质渗透性差,少量残余油即可造成水相的有效渗透率大幅度下降的问题,研究油水界面张力、乳化作用、增溶能力对低渗透岩心残余油饱和度的影响;开发研制PO、EO数分别为9和6的十八烷基胺聚氧丙烯氧乙烯醚双羧酸盐为主表活剂、醇的混合物为助表活剂的增注网状胶束体系;性能评价表明,该体系对不同岩心的恒速降压率在48.5％～ 83.3％,有优异的降压增注作用.

According to the significant decline problem of the effective permeability of water caused by the poor permeability of matrix of low permeability reservoir and a small amount of residual oil, the effect of oil - water interfacial tension, emulsification and solubilization ability on residual oil saturation of low permeability core are studied. Augmented injection mesh micellar system which is composed by octadecylamine polyoxyethylene propylene - ethylene oxide ether bis polycarboxylates in which the number of PO and EO is 9 and 6 respectively - main surfactant and a mixture of alcohols - cosurfactant is developed. Performance evaluation shows that the constant speed buck rate of the system on different cores is between 48.5% and 83.3% which has an excellent effect of reducing pressure and increasing water injection.