耐温耐盐乳液暂堵转向剂制备与性能评价

Optimum Selection and Performance Evaluation of Temporary Plugging Agent for Acidification of Temperature-resistant and Salt-tolerant Emulsion

为改善常规乳液高温易破乳、增黏能力弱、转向能力差的问题,以柴油为油相,以油酸二乙醇酰胺(ODEA)、聚异丁烯丁二酰亚胺(T154)和十二烷基苯磺酸钠(SDBS)为乳化剂,按油水比3∶7制得稳定的耐温耐盐油包水乳状液,评价了乳状液的性能。结果表明,配方为2%ODEA、0.8%T154和0.3%SDBS的油包水乳状液150℃老化12 h的乳化率在85%以上;乳状液粒径在20~50μm之间;乳状液的稳定性和耐温耐盐性较好,在95℃、170 s^-1的条件下乳状液的黏度为295.6 mPa·s;按体积比10∶5与20×10^4mg/L高矿化度水混合后乳状液黏度为7090.2 mPa·s,与柴油混合后其黏度低于50 mPa·s;高浓度酸液可使乳液增黏效果降低,在注酸前应注入水相隔离段塞。该乳状液可有效封堵基质高渗区域与裂缝,实现酸液连续多级转向,可用于高温高矿化度碳酸盐岩油藏。

In order to solve the problems of conventional emulsion,such as easy demulsification at high temperature,weak viscosifying ability and poor steering ability,a high temperature resistance and high salinity tolerance water-in-oil emulsion with 3∶7 oil-water ratio was prepared by using diesel oil as oil phase,oleic diethanolamide(ODEA),polyisobutylene succinimide(T154)and sodium dodecylbenzene sulfonate(SDBS)as emulsifiers.And the properties of emulsion were evaluated.The results showed that the emulsifying rate of the water-in-oil emulsion prepared with 2%ODEA,0.8%T154 and 0.3%SDBS emulsifier was over 85%after aging at 150℃for 12 hrs.The particle size of the emulsion ranged from 20 to 50μm.The emulsion had good stability,temperature and salt tolerance,and the viscosity of the emulsion was 295.6 mPa·s at 95℃and 170 s^-1.The viscosity of the emulsion was 7090.2 mPa·s when it mixed with 20×10^4 mg/L salinity water at volume ratio of 10∶5,and that was lower than 50 mPa·s when it mixed with diesel oil.High concentration acid could reduce the viscosity increasing effect of emulsion.As a result,water phase slug should be injected before acid injection.The emulsion could effectively plug the high permeability area and fracture of matrix,and realize continuous multi-stage turning of acid,which could be used in high temperature and high salinity carbonate reservoir.