摘要
鄂尔多斯盆地东南缘延安气田深层煤层气资源潜力巨大,但受煤层薄、孔隙结构复杂、微幅构造发育及井壁失稳等地质与工程难题制约,其高效开发面临挑战。文章针对延安气田本溪组8#煤与山西组5#煤储层特征,通过优化三开井身结构、井眼轨道设计、钻井提速工具组合及强封堵复合盐钻井液体系,形成了适用于深层煤层气水平井的钻完井技术体系。2024年实施的6口水平井先导试验表明,平均完钻井深3842.33 m、水平段长度937.5 m、钻完井周期75.75 d,储层平均钻遇率79.92%,固井优质率超80%。然而,随着先导试验井实施,存在二开井段钻时慢、周期长、漏失频发,水平段钻井液密度过高及体系复杂等问题,仍需进一步优化改进整体技术。研究成果为鄂尔多斯盆地深层煤层气规模开发提供了技术支撑与改进方向。
The deep coalbed gas resources in the Yan'an Gas Field,located at the southeastern margin of the Ordos Basin,exhibit significant potential.However,their efficient development is challenged by geological and engineering complexities,including thin coal seams,complex pore structures,micro-amplitude tectonic features,and wellbore instability.Targeting the reservoir characteristics of the coal No.8 in the Benxi Formation and coal No.5 in the Shanxi Formation,this study established a safe and efficient drilling and completion technology system for deep coalbed gas horizontal wells.Key innovations include optimized three-section wellbore structures,well trajectory designs,ROP optimization tool assemblies,and a highly plugging composite salt drilling fluid system.Pilot tests of six horizontal wells in 2024 demonstrated an average drilled depth of 3,842.33 m,horizontal section length of 937.5 m,drilling and completion cycle of 75.75 days,the average drilling encounter rate of the reservoir was 79.92%,and cementing quality rate exceeding 80%.However,with the implementation of the pilot test well,there are still problems such as slow drilling time,long cycle,frequent leakage in the second section,high density of drilling fluid in the horizontal section,and complex system,which require further optimization and improvement of the overall technology.These findings provide technical support and improvement directions for the large-scale development of deep coalbed gas in the Ordos Basin.
作者
王波
林进
吴金桥
刘刚
马振锋
杨先伦
马彤
赵正阳
WANG Bo;LIN Jin;WU Jinqiao;LIU Gang;MA Zhenfeng;YANG Xianlun;MA Tong;ZHAO Zhengyang(Natural Gas Research Institute,Shaanxi Yanchang Petroleum(Group)Co.,Ltd.,Xi′an,Shaanxi 710075,China;Shaanxi Provincial Key Laboratory of Continental Shale Gas Accumulation and Development,Xi′an,Shaanxi 710075,China;Gas Field Company,Shaanxi Yanchang Petroleum(Group)Co.,Ltd.,Yan′an,Shaanxi 716000,China)
出处
《钻采工艺》
北大核心
2025年第3期77-83,共7页
Drilling & Production Technology
基金
陕西省创新能力支撑计划“温度-压力-钻井液作用下深部煤岩化学结构演化规律”(编号:2024ZC-KJXX-129)。
关键词
深层煤层气
水平井
复合盐钻井液
钻时慢
漏失
deep coalbed gas
horizontal well
composite salt drilling fluid
low ROP
fluid loss
