Popis: |
This paper introduces the research advances on replacement of CH 4 in Natural Gas Hydrates (NGHs) by use of CO 2 and discusses the advantages and disadvantages of the method on the natural gas production from such hydrates. Firstly, the feasibility of replacement is proven from the points of view of kinetics and thermodynamics, and confirmed by experiments. Then, the latest progress in CH 4 replacement experiments with gaseous CO 2 , liquid CO 2 and CO 2 emulsion are presented Moreover, the superiority of CO 2 emulsion for replacement of CH 4 is emphasized. The latest experiment progress on preparation of CO 2 emulsions are introduced. Finally, the advancements in simulation research on replacement is introduced, and the deficiencies of the simulations are pointed. The factors influencing on the replacement with different forms of CO 2 are analyzed and the optimum conditions for the replacement of CH 4 in hydrated with different forms of CO 2 is suggested. |