气体水合物法开发高寒地区湖盐的相平衡预测

Phase equilibrium prediction of laky salt in severe cold region with gaseous hydrate method

中国高寒地区年平均气温为气体水合物的生成提供了天然的温度条件,也为气体水合物法实现高寒地区湖盐的节能开发提供了可能.提出气体水合物法开发高寒地区湖盐的新方法,以van der Waals-Platteeuw模型为基础,结合杜亚和郭天民提出的计算Langmuir常数的三参数方程和计算电解质溶液中水的活度的Pitzer方程,预测饱和NaCl溶液中甲烷水合物、乙烷水合物和丙烷水合物的相平衡条件,对比饱和NaCl溶液凝固点,发现利用环境冷量实现气体水合物法开发湖盐具有实际可行性;与甲烷、乙烷气体相比,丙烷气更适合用于湖盐开发.

In severe cold region of China, the average temperature there not only makes it available to form the gas hydrate, but also implies the possibility of salt exploration with gas hydrate technology, so that a new idea of salt exploration in severe cold region with gas hydrate technology was proposed. The phase equilibrium conditions of methane gas hydrate, ethane gas hydrate and propane gas hydrate in saturated NaC1 solution were predicted by using Van der Waals-Platteeuw model, in which Langmuir constant and water activity in electrolytic solution was calculated with three-parameter equation presented by Du Ya Guo Tianmin and equation of Pitzer, respectively. Compared with the freezing point of saturated NaC1 solution, the phase equilibrium obtained could demonstrate the feasibility of salt exploitation with gas hy- drate method. It was also found that the propane was the most suitable gas for salt exploitation when compared with the methane and ethane. The result was of great value for salt exploration with this highly effective energy-saving technology.