降黏剂及其施工工艺对火驱稠油油藏注采井间快速连通的影响

Influence of viscosity reducer and its operation technique on rapid injector-producer connection in in-situ combustion heavy oil reservoirs

针对火驱试验区注采井之间连通性差的问题,利用一维火驱物模装置,通过采用“梯次浓度注入降黏剂+脉冲式注气压力调节”等工艺措施,初步探索了火驱试验区注采井之间快速连通的方法。同时,基于油藏中稠油与降黏剂实际作用原理,建立了一种用于评价筛选降黏剂性能的方法,该方法能准确、快速地筛选出适合现场的降黏剂。实验结果表明:在25℃条件下,水溶性降黏剂降黏性能优于油溶性降黏剂,其中3#(丙烯酸类聚合物)水溶性降黏剂降黏性能最佳,在40℃和60℃时降黏率分别达到52.3%、61.2%,油溶性降黏剂耐温性能更好,而采用注采井两端双向注入降黏剂的方法能加快注采井之间的连通。研究成果可为火驱生产提供理论支撑和技术支持。

Aiming at the problem of poor connectivity between injectors and producers of in-situ combustion test area,the method of rapid injector-producer connectivity in the in-situ combustion test area is preliminarily explored by using 1D physical simulation instruments of in-situ combustion and adopting techniques of“echelon concentration injection viscosity reducer+pulse gas injection pressure adjustment”.Based on actual principle of heavy oil and viscosity reducer in reservoir,a method for evaluating and screening viscosity reducer performance is established,which can accurately and quickly screen viscosity reducers suitable for field application.The experimental results show that at 25℃,the viscosity reduction performance of water-soluble viscosity reducer is better than that of oil-soluble viscosity reducer,among which 3#(acrylic polymer)water-soluble viscosity reducer is the best,52.3%and 61.2%at 40℃and 60℃respectively.Oil-soluble viscosity reducer has better temperature resistance,and two-way injection of viscosity reducer at both ends of injectors and producers can speed up the injector-producer connection.The research provides theoretical and technical support for in-situ combustion production.