二氧化碳置换法模拟开采天然气水合物的研究进展

Advance on simulation exploitation of natural gas hydrate by replacement with CO_2

目前实验室模拟开采天然气水合物(NGH)的最主要的方法为外激法,通过注热、降压等方式使水合物分解释放出甲烷(CH4),外激法最大的问题在于水合物的分解容易造成地层结构变化,导致地质斜坡灾害。利用二氧化碳(CO2)在水合物相中置换开采CH4,由于置换过程发生在水合物相中,不改变水合物相结构,因此可以降低地质灾害风险。本文全面介绍了利用CO2在水合物相从NGH中置换CH4的研究进展,从置换可行性、动力学模型、模拟研究、实验研究等方面对当前的研究进行了综述,并为进一步发展置换法开采CH4技术指出了方向。

The main method of simulation exploiting methane（CH4）from natural gas hydrate（NGH）is external stimulation.By heat injection or depressurization,NGH dissociate and release CH4,which causes easily geological slope hazard,however,because of NGH structure damage.The method,replacing CH4 in hydrate with CO2,can dramatically lower the risk due to the replacement occurs in hydrate,and its structure cannot be destroyed.In this paper,the research works on CO2-CH4 replacement is reviewed comprehensively,including feasibility of replacement,kinetics model,simulation and experimental studies,and direction of further research and development is proposed for technologies exploitating CH4 from NGH by replacement method.