CO_2-N_2-THF-H_2O体系水合物的生成和模型计算

Formation and simulative calculation of CO_2-N_2-THF-H_2O hydrate system

对合成氨工业排放的烟道气(9.06%(x)CO_2+90.94%(x)N_2)在四氢呋喃(THF)溶液中进行水合物的生成研究。实验结果表明,6.0%(x)的THF水溶液能显著降低该体系的水合物生成压力,具有工业应用价值。通过文献中纯CO_2、纯N_2在THF溶液中的水合物生成数据拟合得到CO_2-THF和N_2-THF的二元交互作用参数,采用改进PR状态方程计算气体逸度,Wilson活度系数模型计算液相中水的活度、Chen-Guo水合物热力学模型计算CO_2-N_2-THF-H_2O体系的水合物生成压力。Chen-Guo水合物热力学模型计算出的生成压力与实验值、文献值进行比较,平均相对误差分别为11.68%和8.46%。

The formation of the hydrates of flue gas（9.06%（x）CO2＋ 90.94%（x）N2） from synthetic ammonia plants in tetrahydrofuran（THF） solution was investigated. The results showed that the molar fraction 6.0%（x） THF solution could decrease the hydrate formation pressure in the system remarkably. The binary interaction parameters of CO2-THF and N2-THF were obtained by fitting the hydrate formation data of pure CO2 and pure N2 in THF solution from literatures. The gas fugacities were calculated by means of the modified PR state equation and the activity of water in liquid phase was calculated by means of the Wilson activity coefficient model. The hydrate formation pressure of the CO2-N2-THF-H2 O system was calculated by means of the Chen-Guo hydrate thermodynamics model. The calculated formation pressures were compared with experimental data and literature data,and the average absolute relative deviations（AARD） were 11.68% and 8.46%,respectively.