海域天然气水合物地层微生物自修复固井水泥浆的水化控热作用机理  

Mechanism of hydration heat control in microbial self-healing cement slurry for marine gas hydrate bearing sediments

作　　者：李丽霞 谢文卫[1,2,3] 杨胜雄 苏明[4] 于彦江 梁前勇 蒋国盛[5] 刘天乐 史浩贤[1,2,3,5] 唐承相 LI Lixia;XIE Wenwei;YANG Shengxiong;SU Ming;YU Yanjiang;LIANG Qianyong;JIANG Guosheng;LIU Tianle;SHI Haoxian;TANG Chengxiang(Guangzhou Marine Geological Survey,China Geological Survey,Guangzhou,Guangdong 511458,China;Gas Hydrate Engineering Technology Center,China Geological Survey,Guangzhou,Guangdong 511458,China;National Engineering Research Center for Gas Hydrate Exploration and Development,Guangzhou Marine Geological Survey,China Geological Survey,Guangzhou,Guangdong 511458,China;School of Marine Sciences,Sun Yat-Sen University,Zhuhai,Guangdong 519082,China;School of Engineering,China University of Geosciences(Wuhan),Wuhan,Hubei 430074,China;Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou),Guangzhou,Guangdong 511458,China)

机构地区：[1]中国地质调查局广州海洋地质调查局,广东广州511458 [2]中国地质调查局天然气水合物工程技术中心,广东广州511458 [3]天然气水合物勘查开发国家工程研究中心,中国地质调查局广州海洋地质调查局,广东广州511458 [4]中山大学海洋科学学院,广东珠海519082 [5]中国地质大学(武汉)工程学院,湖北武汉430074 [6]南方海洋科学与工程广东省实验室,广东广州511458

出　　处：《地质学报》2024年第9期2766-2780,共15页Acta Geologica Sinica

基　　金：广东省基础与应用基础研究重大项目(编号2020B0301030003);广州市2023年度南沙区重点领域科技计划项目(编号2023ZD017)联合资助的成果。

摘　　要：随着深海天然气水合物资源开发的深入,固井技术成为保障开采安全的关键环节。固井水泥浆的水化热控制对于防止水合物分解、确保井筒稳定性具有重要意义。目前,微生物技术在固井水泥浆中的应用已取得初步进展,尤其是在提高水泥浆力学性能方面,但是在调控水化热方面的研究仍相对较少。本研究旨在探索微生物固井水泥浆在深水水合物地层中的应用前景。通过开展水泥浆水化热测试、热重分析(TGA)和傅里叶红外光谱(FTIR)、扫描电镜(SEM)与能谱仪(EDS)测试,探究了微生物矿化作用对水泥浆水化热及水化过程的影响机理。本文研究表明,微生物自修复固井水泥浆在降低水化热方面具有显著优势,尤其是在水化中后期,其累积水化放热量较对照组降低了13.19%。微生物矿化反应生成的碳酸钙有效抑制了水泥水化反应,导致水化放热峰值滞后,且在水化过程中持续降低水泥浆的水化速率。此外,微生物自修复固井水泥浆中游离水和水化硅酸钙凝胶的含量均高于对照组,而氢氧化钙含量较低。碳酸钙含量与水泥浆水化放热量之间存在最优值,超过3.0%后,水化热开始降低。本研究为解决深水水合物地层固井水泥浆水化放热导致水合物分解的问题提供了新的技术途径,对于开发适应极端海洋环境的固井水泥浆体系具有重要的参考价值。With the development of deep-sea natural gas hydrate resources,cementation technology has become crucial for ensuring the safety of extraction operations.Controlling hydration heat in cement slurry is vital for preventing hydrate decomposition and maintaining wellbore stability.Currently,the application of microbial technology in cement slurry has made preliminary progress,especially in improving the mechanical properties of the cement slurry.However,research on controlling hydration heat is still relatively scarce.This study focuses on the potential of microbial cement slurry in reducing hydration heat and explores its application prospects in deepwater hydrate formations.Hydration heat tests,thermogravimetric analysis(TGA),fourier-transform infrared spectroscopy(FTIR),scanning electron microscopy(SEM),and energy-dispersive spectroscopy(EDS)were used to investigate the influence mechanism of microbial mineralization on the hydration heat and hydration products of cement slurry.Our findings reveal that microbial cement slurry significantly reduces hydration heat,particularly in the mid-tolate stages of hydration,with a 13.19%lower cumulative heat release compared to the control group.The calcite produced by microbial mineralization effectively suppresses cement hydration,delaying the hydration heat peak and continuously reducing the hydration rate during the process.Moreover,microbial cement slurry exhibits higher free water and hydrated calcium silicate gel content,while exhibiting lower calcium hydroxide content compared to the control group.There is an optimal calcite content(around 3.0%)for minimizing hydration;exceeding this threshold leads to a decrease in heat reduction.This research provides innovative solutions to the challenge of gas hydrate decomposition caused by the exothermic reaction of cement slurry hydration in deepwater hydrate layers.It holds significant implications for developing cement slurry systems capable of withstanding the demanding conditions of the open ocean.

关 键 词：天然气水合物地层 固井水泥浆 微生物自修复 水化热 碳酸钙 

分 类 号：P744.4[天文地球—海洋科学]