BZ油田注水井调剖酸化联作体系研究

Study on combined system of profile control and acidification of injection wells in BZ oilfield

针对BZ油田注水井地层非均质强,单一酸化、调剖无法同时满足增注和减小层间矛盾的问题,在室内开展了酸化、调剖联作体系研究。所用配套酸液体系为单步酸酸液体系,实验评价了其缓速、抑制二次沉淀、溶蚀和配伍性等性能,单岩心酸化后渗透率恢复效果良好。配套调剖剂体系主剂采用阴离子型聚合物,评价了其耐酸性能和岩心封堵能力。采用双岩心夹持流动实验装置模拟非均质地层,分析调剖和酸化的注液顺序对联作处理效果的影响。模拟实验结果显示,先调剖后酸化效果明显,低渗岩心渗透率改善倍比为1.52,高渗岩心得到封堵,渗透率改善倍比为0.29,实现了既缩小层间渗透率差异又启动低渗岩心的目标。

Due to the heterogeneity of the formation of injection wells in BZ oilfield,the single acidification and profile adjustment were impossible to increase the injection and decrease the interlayer contradiction simultaneously.So we studied the combined acidification and profile control system indoors.The supporting acid solution system was one-step acid solution system,and its per.formance such as retarding speed,inhibiting secondary precipitation,dissolution and compatibility were evaluated experimentally.And then,we obtained that the permeability recovery was good after single core acidizing.The main agent of profile control agent system is anionic polymer,and its acid resistance and core plugging ability were evaluated.A double-core clamping flow test de.vice was used to simulate the non-homogeneous layerss and analyze the influence of the injection sequence of the profile control and acidizing on the combined treatment effect.The simulation results showed that the acidification effect after profile adjustment was obvious,the permeability improvement ratio of low permeability core was 1.52,the permeability improvement ratio of high per.meability core was blocked,and the permeability improvement ratio was 0.29.The goal of starting low permeability core by reduc.ing the permeability difference between layers was realized.