钻井液与完井液2024，Vol.41Issue(2)：166-171,6.DOI:10.12358/j.issn.1001-5620.2024.02.004
PGA可降解材料作为钻完井液暂堵剂实验研究
Experimental Study on Degradable PGA as Temporary Plugging Agent in Drill-in Fluids
摘要
Abstract
Polyglycolic acid(PGA)has good environment protection property.In laboratory study,the mechanical property,the particle sizes,the thermal stability of the PGA molecules and the crystal density of PGA before and after high temperature soaking are analyzed,the thermal stability of PGA in water and oil is studied,and the application potential of PGA as a temporary plugging agent for drill-in fluids is evaluated.It was found that the physiochemical properties of PGA are highly affected by the liquid environment of a drilling fluid and temperature.In water-based drilling fluids,PGA will degrade at 100℃to oligomers because of the pH of the drilling fluid,and the thermal stability of the PGA molecules and the mechanical strength of PGA are all decreased as well.Strong acid(pH<5)and strong base(pH<9)both accelerate the degradation of PGA,and PGA degrades faster in strong base environment than in strong acid environment.In high temperature oil-based drilling fluids,the PGA particles first swell and then peel and break,and the main body of the PGA particles turns from plastic to brittle,resulting in a decrease in the tensional and compressive strengths of the particles to some extent.PPA plugging experiment shows that after 8 d of soaking in an oil environment,the PGA particles exhibit good plugging performance.These studies show that PGA is more suitable for use in oil-based drilling fluids than in water-based drilling fluids.关键词
钻完井液/可降解/暂堵剂/聚乙醇酸Key words
Drill-in fluid/Degradable/Temporary plugging agent/Polyglycolic acid分类
能源科技引用本文复制引用
董晓强,金冰垚,刘雨涵,钱晓琳,余福春..PGA可降解材料作为钻完井液暂堵剂实验研究[J].钻井液与完井液,2024,41(2):166-171,6.基金项目
中石化科技部前瞻项目"PGA可降解材料在钻井液中的应用前瞻研究"(P22227) （P22227）
中石化科技部攻关项目"准噶尔盆地腹部超深层优快钻井技术研究"(P22134). （P22134）
