摘要
用无固相弱凝胶钻井液完井后,必须采用破胶技术来解除滤饼,以恢复油井产能。传统的氧化破胶剂在运输、储存和使用的过程中存在安全隐患,且选择性差。优选出了具有储存时间长、储存和运输方便的固体中温生物酶破胶剂HSW-L。该破胶剂能以无规则的形式水解PRD弱凝胶钻井液中的增黏剂PF-VIS和降滤失剂PF-FLO分子中的a-1,4葡萄糖苷键,生成短链糊精和小分子糖类,从而起到破胶作用。系列对比评价结果表明,对于还原性甲酸钠加重的无固相弱凝胶钻井完井液,HSW-L的破胶效果明显优于传统氧化破胶剂,与复合破胶剂的破胶效果相当;HSW-L对井筒残余PRD胶液、井壁/筛管泥饼、储层滤液均具有较好的破胶效果;而且与储层原油具有较好的配伍性,同时其还具有环境保护性能、选择性好的优点,值得推广应用。
A bio-enzyme gel breaker,HSW-1,was developed for use at medium temperatures to remove filter cakes formed by the filtration of drilling fluids on bore hole walls.Compare with other gel breakers,HSW-1 is safe in transportation,storage and application and has a better selectivity.HSW-1 promotes and accelerates the hydrolysis of the α-1,4 glucose glycoside bonds in the molecules of the viscosifier PF-VIS and the filtrate reducer PF-FL0 in the PRD weak gel drilling fluid in an irregular mode,thus breaking the gel of the drilling fluid.Evaluation results showed that the gel breaking performance of HSW-1 was better than that of the oxidizing gel breakers and was equivalent to the compound gel breakers in solids-free weak gel drilling fluids weight with sodium formate.Furthermore,HSW-1 had good compatibility with crude in reservoirs.It was environmentally friendly and had a better selectivity than conventional gel breakers.
出处
《钻井液与完井液》
CAS
北大核心
2008年第6期8-10,共3页
Drilling Fluid & Completion Fluid
关键词
防止地层损害
水平井
无固相弱凝胶钻井液
生物酶
破胶
环境保护
Prevent formation damage
Horizontal well
Solids-free weak gel drilling fluid
Bio-enzyme
Gel breaking
Environment protection