水合物法分离混合气中二氧化碳的实验研究

CO2 Separation From Gas Mixtures by Clathrate Crystallization

在小型水合物反应装置上研究了纯水、四氢呋喃(THF)、四丁基溴化铵(TBAB)3种不同体系对二氧化碳水合物生成动力学特性的影响。结果表明THF体系中水合物生成的诱导时间最短,在6~15℃较高的反应温度下仍可以显著改善CO_2水合反应体系的相平衡条件。在4.5~6MPa,0.5~6℃条件下,研究了混合添加剂THF/SDS体系中CO_2/N_2混合气水合物生成特性及其分离效果。结果发现,9%THF体系中加入0.3%SDS可以进一步缩短水合反应诱导时间,增大水合反应系统压降,提高了水合物的储气量,与单一THF体系相比,CO_2的回收率提高了近10%。研究表明THF/SDS混合添加剂可在较高操作温度下改善CO_2/N_2的分离效果,降低分离能耗。

The characteristics of CO2 hydrate formation are investigated with three different solution systems including pure water, tetrahydrofuran（THF） and tetrabutyl ammonium bromide（TBAB）. Results show that THF can improve the phase equilibrium conditions of CO2 hydrate at higher temperature of 6～15℃. The effects of THF and THF/SDS（Sodium dodecyl sulfate） mixture on CO2 separation from CO2/N2 gas mixture have been studied under the conditions of 4.5～6.0MPa, 0.5～6.0℃. The experiment results show that the induction time is further shortened as well as the amount of gas consumption is increased remarkably for 9%THF/0.3%SDS mixture additives system. CO2 occupy the hydrate crystal caves rapidly by adding SDS which can improve the competitiveness of CO2 to N2. CO2 recovery is increased by 10% compared to the system with single THF additive. The results show that mixture additives THF/SDS can improve the effect of CO2 separation from CO2/N2 gas mixture at higher temperature.