沉积物中四氢呋喃水合物生成/解离过程的电阻率演变试验研究  

Experimental Study on the Evolution of Resistivity in the Formation/Dissociation Process of Tetrahydrofuran Hydrate in Sediments

作　　者：马淑芝 李鸿博[2] 孟航 张致能 MA Shu-zhi;LI Hong-bo;MENG Hang;ZHANG Zhi-neng(Wuhan ITRI of GEO-Resources and Environment Co.,Ltd,Wuhan 430078,China;Engineering Faculty,China University of Geosciences,Wuhan 430074,China)

机构地区：[1]武汉地质资源环境工业技术研究院有限公司,湖北武汉430078 [2]中国地质大学(武汉)工程学院,湖北武汉430074

出　　处：《海洋技术学报》2020年第5期64-71,共8页Journal of Ocean Technology

基　　金：国家重点研发计划资助项目(2017YFC0307700,2017YFC0307705);国家自然科学基金资助项目(41672309)。

摘　　要：天然气水合物是一种发展前景广阔的新型战略资源,有关水合物开采的地质探测和监测技术受到广泛关注。研究沉积物中水合物生成和分解过程电阻率的变化特征,对天然气水合物勘探和安全高效开采具有重要意义。本文利用自制的模型试验装置,利用四氢呋喃水溶液,模拟天然气水合物,通过预埋在沉积物中的电阻率测试元件,测量了水合物形成与分解过程中模拟沉积物中的电阻率,据此分析了沉积物中水合物成核、形成与分解过程中各个阶段电阻率的变化规律,并研究了不同四氢呋喃和水配比对水合物生成与分解过程中的阶段特征数据的影响规律。研究结果表明:沉积物中电阻率与水合物含量密切相关,电阻率不仅能够反映水合物的生成和分解过程,而且可以直观反映沉积物中水合物的含量变化。本文揭示的电阻率演变特征对于天然气水合物开采过程的监测具有一定指导价值。Natural gas hydrate is a novel strategic resource with greater development prospects. Geological exploration and monitoring technology related to hydrate exploitation has received much research attention across the world. The formation and decomposition of hydrates in submarine sediments will cause changes in the electrical resistivity of sediments. Therefore it is of great significance to investigate the evolution characteristics of the changes in electrical resistivity during the formation and decomposition of hydrates in sediments, beneficial for the exploration and the safe and efficient extraction of natural gas hydrates. This paper uses the tetrahydrofuran aqueous solution to simulate natural gas hydrates on a home-built apparatus on lab scale. The transient electrical resistivity during gas hydrate formation/decomposition is being measured with resistivity measuring units that have been pre-buried in the sediments. Then this paper deduces the changes in electrical resistivity over various stages of the nucleation, formation and decomposition of hydrates in sediments as well as the influence of different tetrahydrofuran and water ratio on the characteristic data of different stages during hydrate formation and decomposition. The results show that the resistivity in sediments is closely related to the hydrate content. The resistivity not only reflects the formation and decomposition process of hydrate, but also directly reflects the content change of hydrate in sediment. The characteristics of electrical resistivity evolution revealed in this paper will help monitor the existence status of natural gas hydrate during the exploitation process.

关 键 词：四氢呋喃水合物 生成与分解 沉积物 电阻率 水合物饱和度 模型试验 

分 类 号：O742.6[理学—晶体学]