| 초록 |
The CO2/CH4 mixed gas represents sour natural gas and biogas, and CO2 can be one of the main contaminants because it reduces the calorific efficiency of the fuels. In this study, hydrate-based gas separation (HBGS) method was applied to separate CO2 from CO2/CH4 mixed gas. Simulated CO2 (50%) /CH4 (50%) mixed gas and thermodynamic promoters such as tetra-n-butylammonium chloride (TBAC) and tetrahydrofuran (THF) were used for the experiments. The effect of the promoter concentrations on separation efficiency was investigated at 1.0 mol% and stoichiometric concentration of each promoter. In order to identify thermodynamic stability of CO2/CH4 mixed gas hydrate, three-phase equilibria (H-Lw-V) were measured for the pure water and promoter-added systems. Thermodynamic promoters significantly increased the phase equilibrium temperature at a given pressure. The compositions in the vapor and hydrate phases were measured to observe the separation efficiency. The overall experimental results demonstrated that the concentrations of the promoters have a significant influence on thermodynamic stability and CO2 capture characteristics of gas hydrates. |
