THF对低浓度瓦斯水合化分离热力学条件促进作用

Effect of THF on the Thermodynamics of Low-Concentration Gas Hydrate Formatiion

利用可视化分离实验装置,测定了3种浓度(1,0.1和0.01 mol/L)四氢呋喃(THF)溶液中低浓度瓦斯水合化分离热力学参数,色谱分析了分离产物中CH4提纯浓度.对CH4-N2-O2-H2O体系水合物生成相平衡参数Chen-Guo模型计算值和本文实验值进行比较.结果表明:THF的添加有效改善了水合物形成热力学条件,例如17.70℃时,添加促进剂THF后水合物生成压力值降低了7.973 MPa;不同浓度THF溶液对瓦斯水合化分离热力学条件的改善效果不同,所研究的3个浓度体系中,1 mol/L浓度的THF溶液促进效果最好.

A visual separation apparatus was used to measure the thermodynamic parameters of gas hydrate formation in THF solutions at three concentrations： 1, 0.1 and 0.01 mol/L. The concentrations where the separation of the CH4 hydrate product occurred were determined chromatographically. The experimental parameters of the gas hydrate phase equilibrium for the CH4--N2--O2--H2O system were found from the analytical results by using the Chen-Guo model. The results show that THF stabilizes the hydrate formed： for example hydrate formation pressure decreases by 7. 973 MPa （at a the temperature of 17.70 ℃） after the addition of THF. Different concentrations of THF alter the phase conditions differently. In this study the 1 mol/L THF solution showed the largest effect on the thermodynamic conditions for hydrate formation.