四丁基溴化铵-二氧化碳体系中不同结构水合物生成条件测量与模型预测研究

Experimental and Modeling Study on Phase Equilibria of the Diff erent Semiclathrate Hydrates Fomred by Tetra-n-butyl Ammonium Bromide+Carbon Dioxide

水合物法二氧化碳捕集与封存一体化技术具有良好的应用前景,实验准确测定了四丁基溴化铵(TBAB)-二氧化碳水合物的相平衡数据,确定了7~11℃、ω(TBAB)=5%~25%浓度下的二氧化碳水合物生成条件,四丁基溴化铵对二氧化碳水合物具有明显的促进作用,作用强度随浓度的升高而增强。在ω(TBAB)=20%的溶液中,10℃时二氧化碳水合物的生成压力为0.18MPa,相比去离子水体系降低4.12MPa,降幅达95.8%。在实验数据的基础上,基于Chen-Guo水合物模型建立了考虑四丁基溴化铵A、B构型转换的改进模型,模型计算值与实验测量值的绝对误差在0.1MPa以内,具有较高的精度。实现了模型预测准确性的提升,对模型进一步的实际应用具有重要意义。

The integrated technology of carbon dioxide capture and storage in hydrate method has a good application prospect.The hydrate phase equilibrium data of tetra-n-butyl ammonium bromide(TBAB)-carbon dioxide were measured experimentally.The formation conditions of car-bon dioxide hydrate in the range of temperature 7~11℃and concentration ofω(TBAB)=5%~25%were determined.Tetra-n-butyl ammonium bro-mide has obvious promoting effect on carbon dioxide hydrate,and the effect intensity increases with the increase of concentration.In the solution ofω(TBAB)=20%,the formation pressure of CO_(2) hydrate at 10℃is 0.18 MPa,which is 4.12 MPa lower than that of deionized water system,decreasing by 95.8%.Base on the experimental data,an improved model considering A and B configuration conversion of tetra-n-butyl ammonium bromide was established base on the Chen-Guo hydrate model.The absolute error between the model calculated value and experimental measured values are less than 0.1 MPa.The model has high precision.The prediction accuracy of the model is improved,which is of great significance to the further practical application of the model.