自转向酸用缓蚀剂的研究与应用

Study and Application of a Corrosion Inhibitor Used in Self-diverting Acid

目前在筛管完井方式的水平井中,酸化中采用转向酸酸液体系是实现均匀布酸最便捷、有效的方法,缓蚀剂是转向酸酸化安全实施的重要保障,但是目前已有的缓蚀剂大多与自转向酸体系不配伍,影响转向效果,且缓蚀效果大大下降。针对此问题,研制出一种自转向酸用缓蚀剂ZXHS,并对其进行了基本性能评价。由评价结果可知,加有ZXHS的自转向酸在90℃下的静态腐蚀速率可控制在5 g/(m2·h)以内,在120℃下动态腐蚀速率可控制在20 g/(m^2·h)以内,均可达到行业一级品要求。加入ZXHS后自转向酸转向黏度仍可保持在160 mPa·s以上,因此ZXHS的缓蚀效果良好并且不影响自转向酸的转向性能。ZXHS在大港油田和伊拉克艾哈代布油田进行了现场应用,施工效果良好。

Horizontal wells completed with screen pipes are generally acidized with diverting acids, a method with which acid can be evenly distributed in a target zone with ease and effectively. Corrosion inhibitors, an important insurance for safe operation of acidization with diverting acids, are not compatible with most of the self-diverting acids presently in use, therefore the diverting action is negatively affected, and the corrosion inhibitive effciency is remarkably reduced. A self-diverting acid, ZXHS, has recently been developed aimed at addressing these problems. Laboratory evaluation showed that the corrosion rate of ZXHS can be controlled within 5 g/（m2fs） at 90 ℃, and within 20 g/（m2fs） at 120 ℃, all conforming to the industrial requirement of “Grade 1” product. A self-diverting acid treated with ZXHS had viscosity of greater than 160 mPa？s, and good corrosion inhibition and diverting performancecan be achieved with the diverting acid. ZXHS has been used in Dagang oilfeld and Al-Ahdab oilfeld （Iraq）, gaining good operation achievements.