稠油油藏高温多基团交联冻胶封窜体系研究与应用

为解决蒸汽驱开发过程中汽窜严重问题,研制了一种高温多基团交联冻胶封窜体系,并针对其耐温性能、蒸汽封堵性能和耐冲刷性能进行了评价。研究表明:高温多基团交联冻胶封窜体系在130 ℃的高温环境下可以稳定成胶,且在250 ℃条件下放置120 d后凝胶具有很好的稳定性;封堵性能优良,在高温条件下,注入速度为1 mL/min、堵剂注入量为0.8倍孔隙体积时,冻胶封窜体系封堵率高达99.63%,突破压力梯度为7.35 MPa/m;250 ℃条件下,该封窜体系在填砂管内完全成胶后,经高温蒸汽冲刷(30倍孔隙体积)后封堵率一直维持在98.00%以上,耐冲刷性能良好。该封窜体系在现场应用中取得了良好的蒸汽封堵效果,有效解决了稠油油藏蒸汽驱开发过程中的汽窜问题,可为稠油油藏的高效开发提供技术支持。

Study and Application of High-temperature Channeling Blocking System Based on Multi-group Cross Linked Gel for Heavy Oil Reservoirs

In order to address the serious problem of steam channeling in the reservoir development by steam flooding, a high-temperature channeling blocking system based on multi-group cross linked gel was developed. An evaluation was made on its temperature resistance, steam plugging capability, and erosion resistance. It was found in the study that the high-temperature channeling blocking system based on multi-group cross linked gel could stably generate gel under high temperature of 130 ℃, and the gel had a good stability after 120 d at 250 ℃, and excellent plugging performance; the plugging rate of the gel-based channeling blocking system was as high as 99.63% at high temperature when the injection speed was 1 mL/min and the plugging agent volume injected was 0.8 time the pore volume, and the breakthrough pressure gradient was 7.35 MPa/m; at 250 ℃, the channeling blocking system was completely gelling in the sand-filled pipe, and the plugging rate was maintained above 98% after high-temperature steam flushing (30 times the pore volume), with good flushing resistance. The channeling blocking system has proven to be highly effective in plugging with steam by on-site application, effectively solving the problem of steam channeling in the development with steam flooding of heavy oil reservoir, and it can provide a technical support for the efficient development of heavy oil reservoir.