页岩气水平井固井技术研究进展

Research Development of Horizontal Shale Well Cementing Technology

页岩气勘探开发在中国刚起步,目前中国研究多集中在地质和钻井技术,对固井技术涉及较少。为促进页岩气水平井固井技术的研究和发展,在分析总结页岩气储层特征和钻完井工艺特点的基础上,分析指出了页岩气水平井固井技术难点主要集中在油基钻井液置换及界面清洗困难、顶替效率不高、管串安全下入难度大、固井过程中的井漏、固井后早期气窜、对水泥浆和水泥石性能要求高等方面,综述了国内外油基钻井液用前置液技术、页岩气水平井固井水泥浆体系、页岩气水平井固井工艺的研究现状,探讨了目前研究存在的不足。提出了以高效井筒清洗技术、提高套管居中度技术、套管安全下入技术、水泥浆和水泥石性能设计、固井防漏技术、固井压裂一体化设计技术为核心的页岩气水平井固井技术对策。

Exploration and development of shale gas in China is under developed,which the research of lithology and drilling is concerned much now,but the cementing research is not paid much attention to.In order to promote the research and development of horizontal shale well cementing technology,based on the analysis on characteristics of shale gas reservoir,drilling and completion engineering,the technical difficulties such as oil-based mud removal,displacement efficiency,casing running,lost circulation while cementing,early gas channeling,high performance requirements for cement slurry and cement paste are comprehensively analyzed.This paper summarizes the research statuses and shortages on spacer technology for oilbased mud,cement system and cementing practice for horizontal shale wells and put forward that efficient wellbore cleaning technology,improved centralization,safety casing running technology,slurry and paste performances design,leakage-proof cementing technique,cementing and fracturing integrated design were the core technical measures for horizontal shale well cementing.