利用可视化高压流体测试装置对陕北某气田天然气在-11~20℃的温度范围内水合物的形成条件进行了测定。实验结果表明压力的对数lgP与温度t呈线性关系,在-11~-1.8℃和-1.8~20℃范围其斜率不同。另外还比较了气田试产井采出水和纯水2个体系的天然气水合物生成条件,结果显示含盐溶液水合物生成的温度降可用冰点降来确定,同时给出了该气田天然气水合物形成条件的计算方法。

Experimental Investigation on Hydrate Formation Condition of Gas Field in North ShanxiLI Dong-liang~(1,2),YU Guo-bao~(1,2,3),TANG Cui-ping~(1,2),FAN Shuan-shi~(1,2),LIANG De-qing~(1,2)(1.Guangzhou Center for Gas Hydrate Research,Chinese Academy of Sciences,Guangzhou 510640,China;2.Guangzhou Institute of Energy Conversion,Chinese Academy of Sciences,Guangzhou 510640,China;3.Graduate School of Chinese Academy of Sciences,Beijing 100039,China)In this study the formation conditions of natural gas hydrate in salt solution and pure water systems were investigated and compared at the temperatures of-11 to 20 ℃ in a visual high-pressure cell.The compositions of natural gas and salt solution were the same as those of the gas field.The results indicated that the logarithmic pressure and temperature of natural gas hydrate formation were correlated by a linear equation,and the slope at the temperatures of-11 ℃ to-1.8 ℃ was different from that at the temperature of-1.8 ℃ to 20 ℃ for the salt solution system.The formation temperatures for the salt solution system can be determined by the freezing point and the arithmetic to determine the formation conditions was also given.natural gas hydrate;formation condition;phase equilibrium;gas field