Baka and Hongtai, two tight gas reservoirs in the Tuha Oilfield, show characteristics of serious water sensitivity and water block damage as well as great secondary damage to the reservoirs if the regular fracturing and acidizing fluids are used. Therefore, a study is conducted on the alcohol-based fracturing and acidizing fluids. Through the core sample tests, a quantitative analysis is carried out of the damage degree of water sensitivity and water block damage to the reservoirs, on this basis, the optimal concentration and dosage of alcohol and each additives are determined in fracturing and acidizing fluids, thus the specific acidizing fluid system with multi-hydrogen and alcohol is obtained not only to prevent serious water sensitivity and water lock damage but to achieve deep acidization. In addition, the recommendable concentration is also provided for each acid in the system of acidizing fluids. Moreover, the system of alcohol-based fracturing and acidizing fluids is thus designed applicable for the stimulation of Tuha tight gas reservoirs and shows a better performance than the regular ones. With this fluid system applied in 20 wells, a significant increase of well productivity is achieved as a result. This indicates that the new alcohol-based fracturing and acidizing fluids designed independently have excellent adaptability in this study area.

针对吐哈盆地巴喀和红台两个致密砂岩气藏常规的压裂液、酸化液水敏、水锁伤害严重,对储层的二次伤害大的实际情况,开展了醇基压裂液、酸化液技术研究.室内岩心实验定量分析了储层水敏、水锁伤害程度,确定了压裂液及酸液中甲醇及各添加剂的最佳浓度和加量,建立了既能防水锁水敏伤害、又能实现深部酸化的多氢酸+醇酸化液体系,给出了酸液体系中各酸型的推荐使用浓度,并最终研制出了适合该区致密砂岩气藏储层改造的醇基压裂、酸化液体系,其性能指标优于常规压裂、酸化液体系.现场20口井的试验应用取得了显著的增产效果,说明自主研制的醇基压裂液、醇酸酸液在该区具有很好的适应性.