一种新型高温就地自转向酸在塔里木盆地碳酸盐岩油气藏酸化酸压中的应用

塔里木盆地碳酸盐岩油气藏储量较大，埋藏深，储层非均质性强，井段长，常规酸化酸压效果不理想。为此，研制了一种新的高温表面活性剂基清洁就地自转向酸体系，其残酸在150 ℃、170 s^-1下黏度不小于150 mPa·s；使用高温高压流变仪、三岩心并联流动实验仪和核磁扫描仪实验系统，评价了该体系的转向性能。结果表明：就地自转向酸注入压力先随注入体积的增大而增大，当注入一定量时，注入压力急剧升高，最大增加到6.3 MPa，是初始注酸压力的60倍；自转向酸的注入压力是常规酸注入压力的20倍，具有明显的转向性能。该技术在塔里木盆地碳酸盐岩油气藏已完成42口井的酸化酸压应用，取得了很好的效果。

Application of a new type of in-situ diverting acid system in high-temperature acidizing and acid fracturing in the carbonate hydrocarbon reservoirs of the Tarim Basin

A huge volume of gas reserves exists in the carbonate gas reservoirs of the Tarim Basin,which are characterized by a great burial depth and strong heterogeneity.Apart from that,due to a long well section,no satisfactory results can be achieved from acidizing and acid fracturing by regular methods.In review of this,a novel surfactant-based in-situ diverting acid system is designed for acidizing high temperature formations,for which the viscosity of reacted acid is up to 150 mPa·s under the condition of 150 ℃ and 170 s-1.The diverting property of this system is tested by using the HTHP rheometer,three-core parallel flow experimental instrument and NMR scanners experimental system.The results show that the injecting pressure of this in-situ self diverting acid system increases at first with the increase of injection volume.When a certain quantity of such acid is injected,the injecting pressure increases sharply and reaches a maximum of 6.3 MPa,which is 60 times the initial pressure.The injecting pressure of this self diverting acid system with notable diverting performance is 20 times that of the regular acid system.This technique has been used with good performance for acidizing and acid fracturing at 42 wells in the Tarim carbonate hydrocarbon reservoirs.