水合物法分离CH4/CO2研究现状及展望

Hydrate based gas separation technology for CH_4/CO_2 mixtures:a review

介绍了国内外水合物法CH_4/CO_2分离技术的研究现状。首先综述了针对该工艺的促进强化措施,主要包括热力学促进、动力学促进与综合促进。其中,热力学促进能改变反应条件,但会降低分离效率;动力学促进能提高反应速率,但不能改变反应条件;综合促进集合了前两者的优点,但技术还不成熟,是未来的研究重点。接着,讨论了针对该过程的数学模型,主要为热力学模型和动力学模型。目前,所建立的热力学模型多是针对无促进作用体系,且不能同时用于准确地计算相平衡条件和各项组成;动力学模型主要针对水合物生长过程。然后分析了针对该工艺的流程分析现状,即主要停留在实验阶段和平衡条件下的模型计算。最后,基于现状分析,认为提高反应效率,强化热力学、动力学促进和完善热力学、动力学模型等是今后主要的研究方向。

In this work,a review of the hydrate based separation technology for CH4/CO2 mixture was proposed.Firstly,the available promotion approaches including thermodynamic promotions,kinetic promotions and integrated promotions were summarized.The thermodynamic promotion could affect the phase equilibria of gas hydrate,while it would decrease the separation factor of CO2.The hydration reaction rate would be increased with kinetic promotor,but the phase equilibrium data would be invariable.The main research aspect in future,integrated promotion with the advantages of thermodynamic promotion and kinetic promotion,was still on the first stage.Secondly,the thermodynamic models and the kinetic models for the process were discussed.The available thermodynamic models were main proposed for the systems without promotors,and they were always utilized to predict phase equilibrium data or constitute of all phases.The model would predict both of them with high accuracy was still absent.The kinetic models were mainly developed for the process of hydrate growth.Additionally,the kinetic of the nucleation process could not be performed with kinetic model.Then the current situation of the process analysis,mainly focusing on the experimental analysis and the calculation for the phase equilibria situation with model,was presented.Last but not least,the main research aspects in future were also suggested.