天然气水合物CO_(2)+N_(2)驱替置换动力学研究  

Study on Dynamics of Gas Hydrate CO_(2)+N_(2) Displacement

作　　者：关富佳[1,2] 苏向光[3] 何万军 Guan Fujia;Su Xiangguang;He Wanjun(Hubei Key Laboratory of Oil and Gas Drilling Engineering,Wuhan,Hubei 430100,China;Yangtze University,Wuhan,Hubei,430100;CNPC Daqing Oilfield,Daqing,Heilongjiang 163712,China;PetroChina Xinjiang Oilfield Company,Karamay,Xinjiang 833699,China)

机构地区：[1]油气钻采工程湖北省重点实验室,湖北武汉430100 [2]长江大学,湖北武汉430100 [3]中国石油大庆油田有限责任公司,黑龙江大庆163712 [4]中国石油新疆油田分公司,新疆克拉玛依833699

出　　处：《特种油气藏》2024年第3期150-157,共8页Special Oil & Gas Reservoirs

基　　金：湖北省高等学校大学生创新创业训练项目“天然气水合物N 2+CO 2混合气体驱替置换实验研究”(yz2020270)。

摘　　要：为了确定开采天然气水合物过程中注入混合气体(CO_(2)+N_(2))的置换动力学常数,采用室内实验和化工热力学计算等研究方法,在驱替置换温度为274.15 K、置换驱替压力为3.7 MPa的条件下,对3组混合气体驱替置换天然气水合物过程中的置换推动力、水合物置换速率和水合物置换速率常数进行研究,并基于置换动力学模型反演得到水合物置换动力学常数。结果表明,水合物置换过程中,混合气体(CO_(2)+N_(2))的置换推动力和水合物置换速率均随置换时间的增加而快速减小,3组实验中的CO_(2)水合物生成动力学常数较为接近,平均值为0.0252 mol/(h·m^(2)·MPa),对应的CH4水合物分解力学常数也较接近,平均值为0.0316 mol/(h·m^(2)·MPa)。在水合物体系相同的条件下,水合物置换动力学常数只与置换温度和置换压力有关。研究结果对应用混合气体(CO_(2)+N_(2))驱替开采天然气水合物的动态预测具有重要的指导意义。To determine the displacement dynamics constant of mixed gas(CO_(2)+N_(2))injected during the process of natural gas hydrate development,research methods such as indoor experiments and chemical thermodynamic calculations were used.Under the conditions of displacement temperature of 274.15 K and displacement pressure of 3.7 MPa,the driving force,displacement rate and hydrate displacement rate constant during the displacement of natural gas hydrates by 3 groups of mixed gases were studied.And the hydrate displacement dynamics constant was obtained based on inversion of displacement dynamics models.The results show that during the hydrate displacement process,the displacement driving force of the mixed gas(CO_(2)+N_(2))and the hydrate displacement rate decrease rapidly with the increase of the displacement time.The generation dynamics constants of CO_(2) hydrate in the 3 groups of experiments are relatively close,with an average value of 0.0252 mol/(h·m^(2)·MPa),and the degradation dynamics constant of CH 4 hydrate are also relatively close,with an average value of 0.0316 mol/(h·m^(2)·MPa).Under the same conditions of hydrate system,the dynamics constant of hydrate displacement is only related to the temperature and pressure.The research results have important guiding significance for the dynamic prediction of natural gas hydrate development by using mixed gas(CO_(2)+N_(2))displacement.

关 键 词：天然气水合物 混合气体 驱替置换 动力学 逸度差 

分 类 号：TE135[石油与天然气工程—油气勘探]