利用冰冻石英砂模拟冻土水合物的赋存条件，研究了压力对二氧化碳水合物生成特性的影响，在300 mL高压水合物反应釜中于271 K下进行了多组CO2液化压力以上及以下的霰状冰粉包裹的石英砂中水合物生成实验。结果表明，充入的CO2未液化时，初始压力越大，水合反应速率越快，压力越早达稳定状态；充入压力达液化压力后，注入的CO2越多，水合反应速率越快。压力作为水合反应的驱动力，压力越高水合物生成越多，冰的最终转化率越高。采用CO2置换冻土区中甲烷水合物时，控制压力低于液化压力或注入过量的CO2，置换效果更好。
The permafrost region contains a large amount of natural gas hydrate resources. Carbon dioxide replaces methane to recover gas hydrates in the frozen soil, can not only obtain a large amount of natural gas resources, but also can save carbon dioxide gas and reduce the greenhouse effect caused by carbon dioxide emissions. It is a very promising gas hydrate extraction methods. At present, there are few studies on the carbon dioxide replacement of natural gas hydrates by methane production in the permafrost region, and the formation and decomposition characteristics of methane hydrate and carbon dioxide hydrate in the permafrost region have not yet been revealed. In this work, the occurrence condition of frozen quartz sands sleet shape to simulate permafrost gas hydrate, experimental study on effect of stress on carbon dioxide hydrate formation characteristics, several experimental groups were carried out respectively in 271 K, which the generated pressure of carbon dioxide above or below liquefaction pressure in 300 mL high pressure hydration reactor. The results showed that carbon dioxide below freezing temperatures in quartz sand pressure without liquefaction, the higher the initial pressure, the faster the hydration reaction rate and the earlier the pressure will reach the stable state. But above liquefaction pressure, the more the amount of carbon dioxide was filled, the faster the hydration reaction rate was. From the overall trend, the pressure acted as a driving force of the hydration reaction. The higher the pressure, the more formation of carbon dioxide hydrate was, and the higher the final conversion rate was. Therefore, when carbon dioxide was used to replace methane hydrate in the permafrost region, it was necessary to control the pressure below the liquefaction pressure or to inject excess carbon dioxide, and the final conversion rate will increase dramatically.
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