适用于碳酸盐岩储层复合有机缓速酸液体系研究

针对碳酸盐岩油气藏在使用常规酸化措施施工时存在管柱腐蚀严重,酸岩反应速率过快,二次沉淀污染等问题,通过室内实验,优选出了合适的主体酸、缓蚀剂、助排剂和铁离子稳定剂,研制出一套适合碳酸盐岩储层的新型复合有机缓速酸液体系。室内评价了该酸液体系的各项性能指标,结果表明,该酸液体系具有良好的缓速性能、较低的腐蚀速率以及较低的表面张力。岩心模拟酸化实验结果表明,复合有机缓速酸液体系对目标气田储层天然岩心的基质渗透率改善率大于170%,基质酸化效果好于普通盐酸。说明优选的复合有机缓速酸液体系对目标气田储层具有显著的改善作用,可以应用于现场酸化增产作业。

Study on the Composite Organic Retarded Acid Solution System for Carbonate Reservoirs

Aiming at the problems in conventional acidification of carbonate reservoirs, such as serious corrosion of the pipe string, too fast acid-rock reaction rate, second precipitation pollution and so on, the suitable main acid, corrosion inhibitor, auxiliary drainage agent and iron ion stabilizer were optimized through laboratory experiments, a new type of composite organic retarded acid solution system suitable for carbonate reservoirs was developed. The performance indexes of the acid system were evaluated in the laboratory. The results show that the acid system has good retarded performance, low corrosion rate and low surface tension. The result of core simulation acidification experiment shows that the matrix permeability improvement rate of the composite organic retarded acid solution is greater than 170% in the natural core of the target gas field reservoir, its matrix acidification effect is better than ordinary hydrochloric acid. It suggests that the optimized compound organic retarded acid solution has significant improvement effect on the reservoir of the target gas field, and can be applied in the field acidification to increase production.