冻土区裂隙型天然气水合物CO2/N2置换开采机理及实验研究

项目名称： 冻土区裂隙型天然气水合物CO2/N2置换开采机理及实验研究

项目编号： No.51474112

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 矿业工程

项目作者： 孙友宏

作者单位： 吉林大学

项目金额： 82万元

中文摘要： CO2/N2置换开采天然气水合物（简称NGH）机理研究是近年来国内外学者的研究热点。国际上的研究多为纯水介质或多孔介质充填型NGH，而我国祁连山冻土区NGH主要为裂隙介质充填型。由于裂隙介质下水合物赋存方式、气体运移机理、水合物饱和度和气液渗透率等均与孔隙介质型有所差别，这些有可能导致CO2置换裂隙介质下NGH的机理有所不同。 项目首先根据木里盆地冻土区NGH储层特点，对裂隙型NGH进行分类研究；基于此分析，制作模拟实验岩心，开展裂隙介质下CO2-N2-CH4相平衡研究；通过实验与模拟，对CO2-N2-CH4混合气体在含NGH的裂隙介质下的运移机理进行研究；最后，通过电阻率和气相色谱联合测试手段，对CO2/N2混合气体对裂隙介质下NGH的置换机理进行研究。 项目的主要创新点：一是CO2-N2-CH4与H2O的相平衡研究；二是CO2-N2-CH4混合气体在含NGH的裂隙介质下的运移机理研究。

中文关键词： ；裂隙型天然气水合物；CO2/N2置换；开采机理；冻土区

英文摘要： In recent years, mechanism study of the nature gas hydrate (NGH)replacement production by CO2/N2 attracts more and more attention from both domestic and international scientist. The international research mainly focused on NGH occurrence in porous media or pure water, however, NGH in Qilian mountain permafrost mainly occurs in fracture media. Difference of the occurrence mode, gas migration mechanism, hydrate saturation, gas and liquid permeability between fractured media and porous media lead to the different mechanism of fractured NGH replacement production. In this project, the classification of fractured NGH based on the characteristic of NGH reservoir will be studied; and the CO2-N2-CH4 phase equilibrium in fracture media will be researched by a restore simulation core; then, the gas migration mechanism of CO2-N2-CH4 mixture gas in NGH fracture media will be obtained by experiment and simulation; finally, the mechanism of CO2/N2 mixture gas replacement production in fracture media will be studied by combining resistivity measurement and gas chromatography analysis. The main innovations of this project as follows: 1) the phase equilibrium study between CO2-N2-CH4 and H2O in fracture media; 2) the migration mechanism of CO2-N2-CH4 mixture gas in fracture media.

英文关键词： ;Fractrued Nature Gas Hydrate;CO2/N2 Replacement;Production Mechanism;Permafrost