适合稠油油藏注水井的表面改性降压增注技术

摘要

In order to reduce the pressure of water injection wells in heavy oil reservoir ,with surfactant and nan-ometer polysilicon as the main agent ,through a large number of indoor experiment a surface modification decompres-sion and augmented injection system were developed , the formula is 0.5% quaternary ammonium cationic gemini surfactant HAS-1+0.03%nano poly silicon material NPS-L+0.5% anti swelling agent JCL-2.The stability and interfacial properties of the system were studied ,and the wettability and reverse performance of the system were in-vestigated.Research results show that the optimization of surface modification decompression and augmented injec -tion system has good stability and interfacial properties and under 60℃standing for 50 days after ,the oil-water in-terfacial tension of the system stability in 10 -3 mN/m.The system has good wettability reversal ability ,by the addi-tion of the surface modification of decompression and augmented injection liquid saturated core contact angle from 46.5 degrees increased to 134.5 degrees, to transform a hydrophilic surface into a hydrophobic surface .The core displacement experiment results showed that after injection 3 PV of the surface modification decompression and aug-mented injection system ,the pressure of water flooding was decreased by 40%,and the effect was obvious .%为降低稠油油藏注水井注水压力，以表面活性剂和纳米聚硅材料为主要处理剂，通过大量室内实验研制出了一种表面改性降压增注体系，组成为0．5％季铵盐阳离子双子表面活性剂HAS－1＋0．03％纳米聚硅材料NPS－L＋0．5％防膨剂JCL－2。研究了该降压增注体系的稳定性和界面性能，考察了体系的润湿反转性能以及降压增注效果。研究结果表明，优选的表面改性降压增注体系具有良好的稳定性和界面性能，在60℃下静置50 d后，体系油水界面张力稳定在10－3 mN／m数量级。体系具有良好的润湿反转能力，使用加入表面改性降压增注液饱和的岩心接触角从46．5°增大到134．5°，使亲水表面转变为疏水表面。岩心驱替实验结果表明，注入表面改性降压增注体系3 PV后，后续水驱压力降低40％，降压效果明显。