中性酸化压裂一体化滑溜水体系研究

常规压裂作业后，通常采用酸化解除储层伤害，施工步骤多，经济性较差，研发能够实现压裂酸化一体化的液体体系具有重要的现实意义。通过测定中性且水溶性的脂类在不同温度和浓度条件下的有效生成H+浓度及对碳酸盐的溶蚀率，优选了自生酸压裂添加剂，并与滑溜水复配形成新型抑制与解除伤害的自生酸滑溜水压裂液体系；采用摩阻仪和压力传导实验对该体系的摩阻、伤害抑制与解除能力进行研究。研究结果表明:自生酸常温下基本不生酸，在储层温度下具有明显的缓速生酸效果，最终生酸浓度高达8%的等效盐酸，溶蚀碳酸岩量为0.41 g/mL；优选的自生酸与滑溜水配伍性能良好，减阻率达到72.3%；压力传导实验表明传统滑溜水产生了34.8%的储层伤害，该体系不仅不产生伤害，处理后的岩心反而高出原始岩心渗透率29.9%，体现出明显的一体化增产改造效果。 

Study on Neutral Integrated Slick Water System for Acidification and Fracturing

After conventional fracturing operations, acidification is usually used to relieve the damage of the reservoir. There are many operating steps and poor economic performances. The development of a liquid system that can realize both fracturing and acidification has practical significance. In this paper, a class of neutral and water-soluble lipids with the ability to produce H+ ions were selected. The effective generating H+ concentration and the carbonate dissolution rate of these self-generating acids under different temperature and concentration conditions were measured. Then the optimized self-generating acid was combined with slickwater to form a new neutral integrated slickwater system with acidification function. The frictional drag tester and pressure conduction experiment are used to study the drag reduction, scale inhibition and damage relief capabilities of the system respectively. The research results show that self-generating acid does not generate acid at room temperature, and has obvious slow-rate acid generation capacity at reservoir temperature. The final generating acid concentration is as high as 8% equivalent hydrochloric acid, and the ability of dissolving carbonate rock is 0.41 g/mL. The compatibility of optimized self-generating acid and slick water is good, and the drag reduction rate reaches 72.3%. The pressure conduction experiment shows that traditional slickwater produces 34.8% of the reservoir damage. In striking contrast, this new fracturing fluid not only produced no damage, but also improved permeability of the treated core as high as 29.9%. The new fluid proved the obvious integrated stimulation effect of acidification and fracturing.