页岩油二氧化碳注气提采环境下固井水泥环完整性保障技术研究  

Research on the Integrity Guarantee Technology of Cement Ring Under the Environment of Shale Oil Carbon Dioxide Injection for EOR

作　　者：李雪岗 张健 杨建永 LI Xuegang;ZHANG Jian;YANG Jianyong(CNPC Chuanqing Drilling Engineering Co.,Ltd.,Chengdu,Sichuan 610041,China;Drilling&Production Engineering Technology Research Institute,CNPC Chuanqing Drilling Engineering Co.,Ltd.,Xi′an,Shaanxi 710018,China;National Engineering Laboratory for Low-permeability Oil&Gasfield Exploration and Development,Xi'an,Shaanxi 710018,China;China Petroleum Technical Service Corporation Limited,Beijing 100007,China)

机构地区：[1]中国石油川庆钻探工程有限公司 [2]中国石油川庆钻探工程有限公司钻采工程技术研究院 [3]低渗透油气田勘探开发国家工程实验室 [4]中国石油集团油田技术服务有限公司

出　　处：《钻采工艺》2024年第6期93-101,共9页Drilling & Production Technology

基　　金：中国石油集团川庆钻探工程有限公司科技创新项目“二氧化碳酸性介质条件下水泥环完整性研究”(编号:CQ2022B-22-2-3)。

摘　　要：为提高二氧化碳(CO_(2))注气提采环境下固井水泥石(环)的腐蚀完整性,文章从超临界CO_(2)腐蚀机理、防腐添加剂及体系三方面进行科研攻关,探讨不同水泥石在超临界CO_(2)环境养护中宏观力学与微观形貌的相关变化。研究结果表明:超临界态CO_(2)显著加速水泥石结构破坏,抗CO_(2)腐蚀固井水泥石可控制其腐蚀30 d的抗压强度衰退率≤8.56%,遇CO_(2)自修复水泥石具有≥90.22%的高效裂缝自修性,同时该水泥环腐蚀60 d后环空窜逸流量≤0.0002 mL/min,该技术在长庆油田陇东页岩油示范区完成推广应用83井次,固井质量优质率≥93.9%,施工至今无气体窜逸现象发生。该研究结果对提高页岩油二氧化碳注气提采环境下的固井水泥环完整性具有一定的实践指导意义。In order to improve the corrosion integrity of cementing stone(ring)in the environment of carbon dioxide injection and extraction,this paper conducts scientific research from three aspects:supercritical CO_(2)corrosion mechanism,anti-corrosion additives and systems,and explores the relevant changes in macroscopic mechanics and microscopic morphology of different cement stones during maintenance in supercritical CO_(2)environment.The research results show that supercritical CO_(2)significantly accelerates the structural damage of cement stone,and the anti CO_(2)corrosion cementing cement stone can control its compressive strength degradation rate of≤8.56%after 30 days of corrosion.When encountering CO_(2),the self-healing cement stone has an efficient crack self-healing ability of≥90.22%.At the same time,the annular leakage flow rate of the cement ring after 60 days of corrosion is≤0.0002 mL/min.This technology has been promoted and applied in 83 wells in Longdong shale oil demonstration area of Changqing Oilfield,with a high-quality cementing rate of≥93.9%.There has been no gas leakage phenomenon during construction so far.The research results have certain practical guidance significance for improving the integrity of cementing cement sheath in shale oil carbon dioxide injection and extraction environment.

关 键 词：页岩油 CO_(2) 固井水泥环 CO_(2)腐蚀 CO_(2)自修复 水泥环完整性 

分 类 号：TE256[石油与天然气工程—油气井工程]