商三区注入水储层伤害判断及解堵实验

Damage judgment of injected water reservoir and unplugging experiment in Shangsan Region

商河油田商三区沙二下及沙三上储层在注水开发过程中存在地层堵塞的情况。通过对注入水等水样进行水质检测及地层配伍性方面的实验分析，寻找造成堵塞伤害的原因并进行解堵实验。先对注入水所含颗粒粒径、离子质量浓度和结垢趋势等进行分析，发现其存在颗粒堵塞和结垢现象；再使用过滤后的注入水与区块岩心进行驱替实验，发现其存在水敏损害。针对损害类型进行储层岩心酸化及缩膨实验，其中，商三区沙二下岩心在注入12%盐酸+多氢酸+土酸酸体系后，渗透率大幅度提高。

The problem of formation plugging exists in Lower Member reservoir of S₂ and Upper Member reservoir of S₃ in Shangsan Region of Shanghe Oilfield during the process of developing. Through testing water samples quality and analyzing formation compatibility of water samples by experiments, this paper looks for the damage caused by plugging and conducts plugging experiments. By analyzing particle size, ion content and scaling tendency of the injected water, it is found that the particles plugging and scaling phenomenon exist in injected water. Then driving injected water to block core, water-sensitive phenomenon appears. Aimed at the damage type, acidification and reduced swelling experiments are done. The core permeability of Lower Member reservoir of S2 greatly improves after injecting the system of 12% hydrochloric acid+multi-hydrogen acid+mud acid.