The dual action of N_(2)on morphology regulation and mass-transfer acceleration of CO_(2)hydrate film  

作　　者：Jinrong Zhong Yu Tian Yifei Sun Li Wan Yan Xie Yujie Zhu Changyu Sun Guangjin Chen Yuefei Zhang 

机构地区：[1]School of Chemistry and Chemical Engineering,Changsha University of Science and Technology,Changsha 410114,China [2]State Key Laboratory of Heavy Oil Processing,China University of Petroleum,Beijing 102249,China [3]Institute of Environmental and Ecological Engineering,Guangdong University of Technology,Guangzhou 510006,China

出　　处：《Chinese Journal of Chemical Engineering》2024年第9期120-129,共10页中国化学工程学报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(52106002,22378424);Natural Science Foundation of Hunan Province(2023JJ40026);Hunan Provincial Department of Education Scientific Research Project(22B0310);Natural Science Foundation of Guangdong Province(2021A1515010578,2020A1515110693);Shanghai Key Laboratory of Multiphase Materials Chemical Engineering(MMCE2023001).

摘　　要：The morphology characteristics of CH_(4),CO_(2),and CO_(2)+N_(2)hydrate film forming on the suspending gas bubbles are studied using microscopic visual method at supercooling conditions from 1.0 to 3.0 K.The hydrate film vertical growth rate and thickness along the planar gas-water interface are measured to study the hydrate formation kinetics and mass transfer process.Adding N_(2)in the gas mixture plays the same role as lowering the supercooling conditions,both retarding the crystal nucleation and growth rates,which results in larger single crystal size and rough hydrate morphology.N_(2)in the gas mixture helps to delay the secondary nucleation on the hydrate film,which is beneficial to maintain the porethroat structure and enhance the mass transfer.The vertical growth rate of hydrate film mainly depends on the supercooling conditions and gas compositions but has weak dependence on the experimental temperature and pressure.Under the same gas composition condition,the final film thickness shows a linear relationship with the supercooling conditions.The mass transfer coefficient of CH_(4)molecules in hydrates ranges from 4.54×10^(-8)to 7.54×10^(-8)mol·cm^(-2)·s^(-1)·MPa^(-1).The maximum mass transfer coefficient for CO_(2)t N_(2)hydrate occurs at the composition of 60%CO_(2)t 40%N_(2),which is 3.98×10^(-8)mol·cm^(-2)·s^(-1)·MPa^(-1).

关 键 词：Gas hydrate MORPHOLOGY Secondary nucleation Formation kinetics Mass transfer 

分 类 号：TE5[石油与天然气工程—油气田开发工程]