不同相体系下H_(2)S水合物生长过程分子动力学模拟  

Molecular dynamics simulation of growth process of H_(2)S hydrate in different phase systems

作　　者：罗泽东 李爱蓉[1] 刘发平 陆原 LUO Ze-dong;LI Ai-rong;LIU Fa-ping;LU Yuan(College of Chemistry and Chemical Engineering,Southwest Petroleum University,Chengdu 610500,Sichuan,China;China National Offshore Oil Corporation(Tianjin)Oilfield Chemical Co.,Ltd.,Tianjin 300450,China)

机构地区：[1]西南石油大学化学化工学院,四川成都610500 [2]中海油(天津)油田化工有限公司,天津300450

出　　处：《天然气化工—C1化学与化工》2021年第6期116-122,共7页Natural Gas Chemical Industry

基　　金：国家自然科学青年基金(51704252)。

摘　　要：研究H_(2)S水合物的生成机理有助于解决高含硫气藏开采中水合物冰堵的难题。利用分子动力学模拟,分别在H_(2)S气相、溶液相和水合物相的三相体系与H_(2)S溶液相和水合物相的两相体系下,研究了250~285 K温度范围内H_(2)S水合物的生长过程。结果表明:在三相体系下,温度对H_(2)S水合物生长过程影响较大,在260~270 K温度范围内,其最大生长速率为0.120 nm/ns;而在两相体系下,温度对H_(2)S水合物生长过程的影响并不大,在260~285 K温度范围内,其生长速率相差不大,约为0.220 nm/ns。分析认为,H_(2)S分子与H_(2)O分子的扩散系数接近,使得这两种分子在液相中的运动相互协同,造成两相体系下H_(2)S水合物的生长速率大于三相体系。The study of the formation mechanism of H_(2)S hydrate can be helpful to solve the problem of hydrate ice plugging in exploitation of gas reservoirs with high sulfur.In three-phase(H_(2)S gas phase,H_(2)S aqueous solution and H_(2)S hydrate)and two-phase(H_(2)S aqueous solution and H_(2)S hydrate)systems,the growth process of H_(2)S hydrate in the temperature range of 250-285 K was studied by molecular dynamics simulation.The results show that the temperature has a great influence on the growth process of H_(2)S hydrate in the three-phase system,and the maximum growth rate is 0.120 nm/ns,which appears in the temperature range of 260-270 K.However,the growth process of H_(2)S hydrate is not very sensitive to the temperature in the two-phase system,and the growth rate is about 0.220 nm/ns in the temperature range of 260-285 K.The analysis shows that the diffusion coefficient of H_(2)S molecular is close to that of H_(2)O molecular in the two-phase system,so that the movement of the two molecules in the liquid phase is coordinated,making the growth rate of H_(2)S hydrate in the two-phase system higher than that in the three-phase system.

关 键 词：H_(2)S水合物 三相体系 两相体系 生长速率 扩散系数 分子动力学 模拟 

分 类 号：TE31[石油与天然气工程—油气田开发工程] TQ019[化学工程]