寒带海域永冻层的力学特性对油气钻井的挑战  

Challenges of the mechanical properties of permafrost in frigid sea areas to oil and gas drilling

作　　者：朱亮[1,2,3] 范西哲 李军伟[4] 邹和均 楼一珊[1,2,3] 李忠慧[1,2,3] ZHU Liang;FAN Xizhe;LI Junwei;ZOU Hejun;LOU Yishan;LI Zhonghui(Circulation Loss Control Technology Research Department,National Engineering Laboratory of Oil&Gas Well Drilling Technology//Yangtze University,Wuhan,Hubei 430100,China;Key Laboratory of Drilling and Production Engineering for Oil and Gas//Yangtze University,Wuhan,Hubei 430100,China;Petroleum Engineering College,Yangtze University,Wuhan,Hubei 430100,China;CNOOC Services Limited,Tianjin 300459,China;Engineering Technology Department,CNPC Xibu Drilling Engineering Co.,Ltd.,Urumqi,Xinjiang 830011,China)

机构地区：[1]油气钻井技术国家工程实验室防漏堵漏技术研究室·长江大学 [2]油气钻采工程湖北省重点实验室·长江大学 [3]长江大学石油工程学院 [4]中海油田服务股份有限公司 [5]中国石油集团西部钻探工程有限公司工程技术处

出　　处：《天然气工业》2020年第11期110-119,共10页Natural Gas Industry

基　　金：中海油服股份有限公司科研项目“喀拉海域目标区域钻井技术前期研究”(编号:G1812A-A11C222)。

摘　　要：全球海洋油气勘探开发活动目前主要集中在热带和温带地区,但随着世界能源发展格局的变化以及油气需求量的不断增长,寒带海域的油气资源越来越受到关注和重视。永冻层所具有的力学性质特殊性,给寒带海域油气开采带来了极大的困难与挑战,目前国内对于寒带海域油气钻井技术鲜见报道。为此,通过调研国内外的文献资料,分析了永冻层在不同状态下的力学特性及其在井筒安全、钻井平台、钻井液体系、固井和天然气水合物等方面所存在的风险,综合阐述了套管隔热、优快钻井、低温钻井液、低温固井及钻井平台设计等永冻层油气钻井关键工艺及配套技术的现状。研究结果表明:①永冻层所在的环境温度对其力学性质较为敏感,温度是稳定永冻层力学性质以及实现安全快速钻井的关键因素;②合理而高效的保温隔热技术、低温流体工艺技术和抗冰钻井平台技术是确保海域永冻层钻井顺利实施的核心技术。结论认为,寒带海域油气资源丰富,在弄清永冻层分布特征和力学特性的基础上,研发并掌握寒带海域相关钻井技术对于提高我国海洋钻井技术的国际竞争力具有重要的意义。At present,global offshore oil&gas exploration and development activities are mainly distributed in tropical zones and temperate zones.With the change of worldwide energy development pattern and the continuous increase of oil and gas demand,however,oil and gas resources in frigid sea areas get more and more concerns and attentions.The particular mechanical properties of permafrost bring great difficulties and challenges to oil and gas production in frigid sea areas.At present,there are few domestic reports on drilling technology used in the frigid sea areas.By investigating domestic and foreign literatures,this paper analyzes the mechanical characteristics of permafrost under different states,as well as its risks in terms of wellbore safety,drilling platform,drilling fluid system,cementing and natural gas hydrate.Then,the status of key process and its supporting technologies for well drilling in permafrost are illustrated comprehensively,including casing insulation,optimized fast drilling,low-temperature drilling fluid,low-temperature cementing and drilling platform design.And the following research results were obtained.First,the mechanical properties of permafrost are more sensitive to its environmental temperature,which is the key factor for stabilizing the mechanical properties of permafrost and realizing safe and fast drilling.Second,the core technologies to ensure smooth drilling in offshore permafrost include reasonable and efficient thermal insulation technology,low-temperature fluid technology and anti-ice drilling platform technology.In conclusion,there are abundant oil and gas resources in frigid sea areas.In order to improve the competitiveness of China's offshore drilling technologies in the world,it is of great significance to develop and master the related drilling technologies used in the frigid sea areas after clarifying the distribution characteristics and mechanical properties of permafrost.

关 键 词：寒带海域 永冻层 力学特性 钻井工程 钻井风险 低温 关键技术 优快钻井 

分 类 号：TE52[石油与天然气工程—油气田开发工程]