机械充氮泡沫水泥浆固井技术在页岩气井的应用  

Application of Mechanical Nitrogen Filling Foam Cementing Technique in Shale Gas Wells

作　　者：匡立新 刘奎 丁士东 初永涛[2,3] 周仕明 姜政华[1] 肖京男 Kuang Lixin;Liu Kui;Ding Shidong;Chu Yongtao;Zhou Shiming;Jiang Zhenghua;Xiao Jingnan(Sinopec East China Oil&Gas Company;State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development;Sinopec Research Institute of Petroleum Engineering)

机构地区：[1]中国石油化工股份有限公司华东油气分公司 [2]页岩油气富集机理与有效开发国家重点实验室 [3]中国石油化工股份有限公司石油工程技术研究院

出　　处：《石油机械》2022年第7期26-33,共8页China Petroleum Machinery

基　　金：中石化科技部项目“深层页岩气井固井水泥环失效机理与密封性评价方法研究”(P21056);企业创新发展联合基金集成项目“海相深层油气富集机理与关键工程技术基础研究”(U19B6003)。

摘　　要：复杂工况下页岩气井固井存在漏失、顶替效率低和密封效果差等难题,机械充氮泡沫水泥浆固井技术是解决复杂工况下固井难题的重要手段。为此,基于氮气气泡可压缩性,研究了泡沫水泥浆井内密度计算方法和控制方法,建立了泡沫水泥浆解决页岩气井固井难题的工艺和方法,并投入现场应用。现场应用结果表明:①在浅层漏涌同存的页岩气井中,低密度泡沫水泥浆的自膨胀性能有效防止固井水泥浆漏失及气侵;②在超低密度钻井液漏失井中,泡沫水泥浆固井实现了油基钻井液欠密度固井,防止了固井水泥浆漏失,固井质量更优;③在解决浅表层漏失及井壁垮塌问题井中,泡沫水泥浆以低于清水的密度实现水泥浆上返并固结井壁和堵漏,使浅表层漏失井建井周期缩短50%以上,经济效益显著。该技术对解决页岩气井复杂工况下的固井难题具有指导意义。Shale gas wells under complex conditions are faced with some cementing problems such as lost of circulation,low displacement efficiency and poor sealing effect.Mechanical nitrogen filling foam cementing technique is an important method to solve these problems.Therefore,based on the compressibility of nitrogen bubbles,the methods to calculate and control the foam cement slurry density were studied,and the technique of foam cement slurry to solve the cementing problem of shale gas wells was developed and put into field application.The field application shows that:①in shale gas wells with shallow leakage and gushing,the self-expansion property of low density foam cement slurry can effectively prevent the leakage and gas invasion of cement slurry;②in the wells with leakage of ultra-low density drilling fluid,foam cementing realizes the under-density cementing of oil-based mud,which prevents the leakage of cementing slurry and has excellent cementing quality;③in solving the problems of shallow surface leakage and borehole wall collapse,foam cement slurry can realize the cement slurry return and consolidating borehole wall and plugging the leakage with a density lower than that of clear water,which shortens the well construction period of shallow surface leakage wells by more than 50% and has remarkable economic benefits.This technique has guiding significance and provides reference for solving the cementing problem of shale gas wells under complex working conditions.

关 键 词：泡沫水泥浆 机械充氮 固井 漏失 页岩气井 

分 类 号：TE256[石油与天然气工程—油气井工程]