界面改性提高碳酸盐岩有水气藏渗流能力

Seepage Capacity Improvement of Carbonate Gas Reservoirs with Water by Interfacial Modification

舒 政 熊 颖 许成军 赵万伟 冯茹森

SHU Zheng XIONG Ying XU Chengjun ZHAO Wanwei FENG Rusen

针对碳酸盐岩有水气藏水侵大幅度降低产量的问题，采用界面改性剂（硅烷偶联剂）对碳酸盐岩表面进行 超疏水改性，通过室内多孔介质流动实验对比研究了界面改性前后对水相、气相及气液两相渗流能力的影响。 结果表明，在界面改性剂质量分数为3%时，改性后的碳酸盐岩与自来水的接触角为153°，碳酸盐岩的界面达到 超疏水状态。与改性前（接触角为0°）相比，超疏水状态的碳酸盐岩在单相恒压（0.05～0.40 MPa）注入条件下，单 独水相渗流速度可提高72.1%～85.9%，单独气相的渗流速度可提高52.9%～72.5%；在气相恒压（0.3 MPa）、水相 恒流（0.05～0.20 mL/min）的两相流条件下，填砂管流出端的出液时间可降低41.0%～47.4%，气相渗流速度可提 高102.1%～104.5%；在气相及水相均为恒压（0.07～0.30 MPa）的两相流条件下，碳酸盐岩界面改性为超疏水时， 水相进入孔隙中的量可降低75.6%～100.0%，气相渗流速度可提高111.1%～200.0%。通过对有水气藏近井地带 进行超疏水界面改性，水相在孔隙中的毛细管力变为阻力，可以有效阻止地层水进入近井地带孔隙，降低水侵程 度；同时，可降低气相在孔隙表面的黏性摩擦力，水相在界面产生“滑移效应”，降低气相及水相渗流阻力，最终提 高气藏产量。

Water invasion in carbonate rock gas reservoirs with water can greatly reduce the production. In view of this problem，the surface of carbonate rock was superhydrophobically modified by interface modifier（silane coupling agent）. The influence of interface modification on the percolation ability of water phase，gas phase and gas-liquid two-phase was studied through porous medium flow experiments. The results showed that when the mass fraction of interface modifier was 3%，the contact angle between modified carbonate rock and water was 153°，and then the interface of the carbonate rock reached a superhydrophobic state。Under the condition of superhydrophobic carbonate rock and single-phase constant pressure（0.05—0.40 MPa）injection，the seepage velocity of single water phase was increased by 72.1%—85.9%，and that of single gas phase was increased by 52.9%—72.5%， compared with that before modification（contact angle 0°）. Under the condition of two-phase flow with gas phase constant pressure （0.3 MPa）and water phase constant flow（0.05—0.20 mL/min），the outlet time of sand filling pipe was reduced by 41.0%— 47.4%，and the seepage velocity of gas phase was increased by 102.1%—104.5% . When gas phase and water phase were both two-phase flow with constant pressure（0.07—0.30 MPa），the amount of water phase entering the pores was reduced by 75.6%— 100.0% ，and the seepage velocity of gas phase was increased by 111.1% —200.0% after the interface of carbonate rock was modified to superhydrophobic. By modifying the superhydrophobic interface in the near wellbore zone of gas reservoirs with water， the capillary force of water phase in the pores became resistance. It could effectively prevent formation water from entering the pores of near wellbore zone and reduce the degree of water invasion. At the same time，it could reduce the viscous friction force of gas phase on the pore surface，and then the water phase produced a“slip effect”at the interface，reducing the seepage resistance of gas and water phases，ultimately increasing the production of gas reservoir.

10.19346/j.cnki.1000-4092.2024.02.010