塔里木盆地超深天然气井全过程塞流防漏注水泥技术  

Plug flow based full-process leakage-proof cementing technology for ultra-deep gas wells in the Tarim Basin

作　　者：李晓春[1] 李坤[1] 刘锐[1] 黄盛[2] 辜涛[2] 张兴国[2] 郭小阳[2] 

机构地区：[1]中国石油塔里木油田公司 [2]"油气藏地质及开发工程国家重点实验室".西南石油大学

出　　处：《天然气工业》2016年第10期102-109,共8页Natural Gas Industry

摘　　要：塔里木盆地库车坳陷山前构造带是典型的超深超高压高温复杂天然气藏,盐膏层段和储层钻井均为多压力层段,如何保障尾管固井既要压稳产层又要防止水泥浆漏失,成为该区块确保气井水泥环完整性的关键。为此,提出了全过程塞流注替水泥浆解决方案,以控制注水泥当量循环密度(ECD)和水泥浆雷诺数为核心,建立了裸眼地层承压能力获取、塞流注替排量和下套管速度计算方法 ;结合盐膏层和储层井段小间隙、偏心、高温以及塞流注替时间长的特点,完成了固井工作液外加剂、外掺料优选以及工作液用量设计。该区4井次现场应用试验结果表明,以控制ECD、水泥浆雷诺数为核心的塞流注替方法能有效防止漏失,隔离液、水泥浆体系能满足全过程塞流注替要求。结论认为,该项固井技术能降低漏失风险,提高顶替效率,提高尾管固井质量,为解决库车山前构造带"三超"气井固井难题提供了新的技术途径。The piedmont structural belt of Kuqa depression in the Tarim Basin is a typical ultra-deep complex gas reservoir with extra high pressure and high temperature, and its gypsum salt layer and reservoir is divided into multiple pressure intervals. The key for complete cement sheath of gas wells is to surely stabilize pay zones and prevent slurry loss by means of liner cementing. In this paper, the solution of full-process plug flow injecting and displacing slurry was put forward, and the method to obtain open-hole formation bearing capacity and calculate plug flow injection and displacement rate and casing lowing velocity was developed with cement equivalent cir- culating density （ECD） and slurry Reynolds number as the core. Then, the additive and blend of cementing fluid were optimized and the working fluid volume was designed with the characteristics of hole sections in gypsum salt layers and reservoirs taken into consideration, such as small gap, eccentricity, high temperature and long plug flow injection and displacement period. This method was tested on site by four well times. It is shown that the plug flow injection and displacement method with ECD and slurry Reynolds number control as the core can prevent leakage effectively, and the spacer fluid and slurry system can satisfy the requirements of full-process plug flow injection and displacement. It is concluded that this cementing technology can reduce leakage risk, increase displacement efficiency and improve liner cementing quality, so it provides a new technical way to solve the cementing difficulty of ＂Three-Highs＂ gas wells in the Kuqa piedmont structural belt.

关 键 词：塔里木盆地 库车山前构造带 高温高压 超深天然气井 盐膏层 储集层 漏失 塞流 顶替 尾管固井 

分 类 号：TE256[石油与天然气工程—油气井工程]