中文摘要：

在全面综述国内外天然气水合物开采技术研究现状的基础上,重点介绍了国内外CO2置换开采天然气水合物的研究进展,分别从热力学和动力学角度分析了置换反应过程的可行性.现有的研究主要集中在自由饱和水体系,而自然界中天然气水合物主要赋存于海底沉积层和永久冻土层中,需结合天然气水合物赋存的自然环境条件,研究其动力学过程,揭示置换反应过程的内在机理.最后指出了CO2置换开采天然气水合物尚存在的问题和今后的研究方向.

英文摘要：

The current exploitation methods of natural gas hydrate domestically and oversea were comprehensively summarized with focus on the research progress in the exploitation methods of CO2 replacement. Then the feasibility of replacement between CO2 and CH4 hydrate was theoretically analyzed based on reaction kinetics and thermodynamics, respectively. However, previous research mainly focused on the free saturated water system, and natural gas hydrate distributed in sediment of seafloor and permafrost region. Therefore, it is necessary to study the dynamic process and reveal the intrinsic mechanism of replacement reaction. Finally, the potential problems and development direction in the future were point out in research on exploitation methods of CO2 replacement of natural gas hydrate.