一种溶黏型仿生自愈合水泥浆体系  

A viscosity-soluble type biomimetic self-healing cement slurry system

作　　者：郑友志 佘朝毅[2] 付洪琼 郭小阳[3] 汪瑶[2] ZHENG Youzhi;SHE Chaoyi;FU Hongqiong;GUO Xiaoyang;WANG Yao(Engineering Technology Research Institute,PetroChina Southwest Oil&Gasfield Company,Guanghan,Sichuan 618300,Sichuan,China;PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan 610212,China;Southwest Petroleum University,Chengdu,Sichuan 610500,China)

机构地区：[1]中国石油西南油气田公司工程技术研究院 [2]中国石油西南油气田公司 [3]西南石油大学

出　　处：《天然气工业》2023年第5期63-70,共8页Natural Gas Industry

基　　金：中国石油西南油气田公司科研项目“自愈合水泥浆评价方法研究”(编号:20220302-02)。

摘　　要：随着固井水泥浆技术的发展,固井自愈合技术已然成为预防和治理油气窜、提高水泥环长期密封能力最为有效的技术之一。针对固井水泥环长期密封性能失效引发的环空油气窜技术难题,基于“先防后堵”的技术思路,从化学仿生的角度,研发了一种溶黏型仿生自愈合水泥浆体系,分别评价了该仿生自愈合水泥浆体系工程性能和凝固后的自愈合水泥石力学性能,并通过劈裂造缝的方式,评价了自愈合水泥石在甲烷养护条件下的力学性能恢复能力和渗透率的降低率。最后通过SEM微观测试和红外光谱分析了该自愈合水泥的愈合机理。研究结果表明:①水泥石力学性能优异,在抗压强度降低15%的情况下水泥石弹性模量减少41%,显示出良好的韧性,起到了“先防”的作用;②破坏后的水泥石遇烃激发,能生成一种溶黏型凝胶状酯类物质,重新黏合水泥石骨架,自愈合水泥石在甲烷养护条件下抗压强度恢复率达94.5%,抗折强度恢复率达58.6%,气测渗透率降幅为99%,液测渗透率降幅为100%,起到了“后堵”的作用。结论认为,溶黏型仿生自愈合水泥浆体系可有效实现固井完整性并在水泥环破坏后通过自愈合实现长期密封完整性,为防止环空异常带压这一油气井生产安全隐患提供了有力的技术支撑,有利于解决固井水泥环长期密封性能失效引发的环空油气窜技术难题。With the development of cementing slurry technology,cementing self-healing technology has become one of the most effective technologies to prevent and treat oil and gas channeling and improve long-term sealing capacity of cement sheath.To solve the technical problem of annulus oil and gas channeling caused by the long-term sealing failure of cement sheath,this paper researches and develops a kind of viscosity-soluble type biomimetic self-healing cement slurry system from the perspective of chemical biomimetics,based on the technical idea of“prevention before blocking”.Then,the engineering performance of this biomimetic self-healing cement slurry system and the mechanical property of self-healing set cement are evaluated respectively.In addition,the mechanical recovery capacity and permeability reducing rate of the self-healing set cement conserved with methane are evaluated by creating fractures through splitting.Finally,the healing mechanisms of the self-healing cement are analyzed by means of SEM microscopic test and infrared spectrography.And the following research results are obtained.First,the set cement has excellent mechanical property.When the compressive strength decreases by 15%,the elastic modulus of set cement decreases by 41%,showing good toughness to play the role of"first prevention".Second,when meeting hydrocarbon,the damaged set cement is excited to generate a kind of viscosity-soluble type gelatinous ester substance,which re-bonds the skeleton of the set cement.When the self-healing set cement is conserved with methane,its compressive strength recovery rate is up to 94.5%,flexural strength recovery rate is 58.6%,gas log permeability drops by 99%,and liquid log permeability drops by 100%,so as to realize"blocking later".In conclusion,the viscosity-soluble type biomimetic self-healing cement slurry system can effectively achieve cementing integrity and long-term sealing integrity through self-healing after the damage of cement sheath,which provides a strong technical support for preventing the

关 键 词：自愈合 溶黏型 水泥浆 水泥石 评价方法 先防后堵 环空带压 

分 类 号：TE256[石油与天然气工程—油气井工程]