摘要
目前在实施冻胶阀欠平衡完井时,破胶方式主要为钻头机械破胶或钻杆注入破胶剂破胶,缺少能随胶液同时注入井筒的一种延迟破胶剂。在施工完成后,自动进行破胶作业,可节约现有破胶方式下的起下钻作业时间。以正硅酸乙酯(TEOS)为前驱体,采用溶胶-凝胶法制备以二氧化硅为外壳、过硫酸铵为芯材的具有核壳结构的延迟破胶剂。研究TEOS、水和丙酮的用量、反应温度、pH值对包覆效果的影响,结果表明,当TEOS、水、丙酮和过硫酸铵的物质的量的比为3∶30∶10∶1、温度为40℃、pH值为6、反应时间为12 h时,所得的延迟破胶剂能满足120℃下,延迟破胶5 d的欠平衡完井作业要求。采用扫描电镜对延迟破胶剂进行表征,证实二氧化硅包覆层的存在。
In underbalanced well completion with gel valve, gel breaking has always been performed with drill bit or by injecting gel breaker through the drill pipe. In this gel breaking operation, a delayed gel breaker is not available right now. If gel breaking can be performed automatically after well completion, time spent in tripping the drill pipe can be saved. To realize automatic gel breaking, a delayed gel breaker has been developed through sol-gel method, with tetraethyl orthosilicate(TEOS) as the precursor, SiO2 as the shell and ammonium persulfate as the core. Study on the effects of concentrations of TEOS, water and acetone, reaction temperature and pH on the coat effect showed that delayed gel breaker that satisfies the need of delaying gel breaking for 5 days at 120 ℃ can be obtained in the following conditions: molar ratio of TEOS, water, acetone and ammonium persulfate of 3∶30∶10∶1, temperature of 40 ℃, pH of 6 and reaction time of 12 h. Characterization of the delayed gel breaker obtained with SEM has proved the existence of the coating SiO2.
作者
沈园园
王在明
朱宽亮
吴艳
SHEN Yuanyuan;WANG Zaiming;ZHU Kuanliang;WU Yan(Drilling and Production Research Institute of Petrochina Jidong Oilfield,Tangshan,Hebei,063000)
出处
《钻井液与完井液》
CAS
北大核心
2020年第1期121-126,共6页
Drilling Fluid & Completion Fluid
基金
国家科技重大专项“渤海湾盆地黄骅坳陷滩海开发技术示范工程”(2011ZX05050)。
关键词
冻胶阀
欠平衡完井
溶胶-凝胶法
核壳结构
延迟破胶剂
Gel valve
Underbalanced well completion
Sol-gel method
Core-shell structure
Delayed gel breaker
