非均质多孔介质中水合物生长及赋存机理研究

The growth and occurrence law of the natural gas hydrates in heterogeneous porous media determine the important basic characteristics, such as acoustic response rate, mechanical strength and effective heat transfer, and influence the development and improvement of the natural gas hydrates resource exploration, safety assessment and highly efficient technology directly. Under this background, this project aims at the whole process of the hydrates formation in heterogeneous porous media, by using MRI technology and microfocus X-ray CT experimental method and simulation. Moreover, considering various influence factors of the hydrates first/second formation process, the control mechanism of heterogeneity and surface characteristic of the heterogeneous porous media, hydrates varieties and formation conditions on the hydrates formation and occurrence law in heterogeneous porous media will be ascertained in detail. The internal relationship between the hydrates and heterogeneous porous media would be established. Finally, this study will reveal the mechanism of the hydrates formation and occurrence law in sediments, and provide the theoretical basis for the exploration and high efficiency exploitation of natural gas hydrate in the future.

非均质多孔介质中天然气水合物生成及赋存规律，决定着天然气水合物沉积物的声、热、力等重要基础物性，对天然气水合物的资源勘探、安全评估和高效开发有着重要意义。本项目以此为背景，利用微观动态可视化实验方法与成核动力学模拟相结合，针对非均质多孔介质中水合物生成的全历程开展分析研究，探明多孔介质的非均质性、多孔介质骨架表面特性、水合物种类以及生成环境对水合物生成过程及赋存规律的控制机理，揭示水合物沉积物储层内水合物与多孔介质之间的内在联系，最终阐明沉积物中天然气水合物生成与赋存规律机理，为我国未来天然气水合物资源的勘探与高效开采提供基础理论支持依据。

天然气水合物作为新一代清洁能源，其勘探和开发技术研究正处于关键的突破阶段。非均质多孔介质中天然气水合物生成及赋存规律，决定着天然气水合物沉积物的声、热、力等重要基础物性，对天然气水合物的资源勘探、安全评估和高效开发有着重要意义。本项目以此为背景，自主设计开发了一套多孔介质中水合物原位生成分解和流动特性实验系统，改进发展了多孔介质内核磁共振成像脉冲序列方法，实现了水合物赋存规律及分解过程中流动特性的动态可视化分析，并成功应用到多孔介质内多相渗流研究，探明了水合物在多孔介质中的生长规律，阐释了天然气水合物分解过程沉积层多孔介质孔隙结构变化以及气、水渗透特性，为天然气水合物资源成藏分析以及安全、高效资源化开采提供了基础数据与理论支持。.另外，为满足针对于复杂多孔介质的成型的要求，提出了一种激光烧结/失效复合（Laser sintering and invalidating composite，LSIC）的3D打印方法。该方法旨在一方面突破常规SLS法中窄线宽扫描存在的内应力控释困难及粉料粘接强度不均、加工效率低的瓶颈，另一方面解决课题组前期已取得专利的轮廓失效打印这一基础方法中存在的材料浪费、后处理工序复杂等困难。新原理结合两者优点实现打印效率、精度、强度、易用性的平衡。