摘要
天然气水合物作为一种潜在的新型潜在替代能源,分布广泛、储量巨大。水合物生成动力学特性对于了解自然界天然气水合物形成规律与水合物相关技术应用具有重大意义。针对甲烷水合物生成动力学特性进行研究,设计开发了甲烷水合物生成测试系统,研究了不同温度和不同孔隙粒径的多孔介质对于水合物生成动力学的影响。结果表明,随着温度的降低以及多孔介质孔隙粒径的减小,甲烷水合物生成过程中的气体消耗速率越快,生成结束时消耗的气体的量越多。同时,利用水合物生成多步骤机制模型,获得了甲烷水合物生成过程各中间产物的变化规律。
As a potential new alternative energy, natural gas hydrate is widely distributed and has huge reserves. The kinetic characteristics of hydrate formation are of great significance for understanding the laws of natural gas hydrate formation in nature and the application of hydrate technology. In view of the kinetic characteristics of methane hydrate formation, methane hydrate formation test system was designed and developed. The effects of porous media with different particle size and different temperature on the kinetics of hydrate formation were studied. The results showed that with the decrease of temperature and the decrease of particle size of porous media, the rate of gas consumption was faster during the formation of methane hydrate, and the more gas were consumed at the end of the formation. At the same time, by using the multi-step mechanism model of hydrate formation, the change rules of the intermediate products in the process of methane hydrate formation were obtained.
引文
[1] CLENNELL M B,HOVLAND M,BOOTH J S,et al.Formation of natural gas hydrates in marine sediments 1.Conceptual model of gas hydrate growth conditioned by host sediment properties [J].Journal of Geophysical Research Solid Earth,1999,104(B10):22985-23003.
[2] KVENVOLDEN K A.A review of the geochemistry of methane in natural gas hydrate [J].Organic Geochemistry,1995,23(11-12):997-1008.
[3] LEE H J,JU D L,LINGA P,et al.Gas hydrate formation process for pre-combustion capture of carbon dioxide [J].Energy,2010,35(6):2729-27337.
[4] CLENNELL M B,HENRY P,HOVLAND M,et al.Formation of natural gas hydrates in marine sediments:gas hydrate growth and stability conditioned by host sediment properties [J].Annals of the New York Academy of Sciences,2010,912(1):887-896.
[5] ZHONG Y,ROGERS R E.Surfactant effects on gas hydrate formation [J].Chemical Engineering Science,2000,55(19):4175-4187.
[6] BALLARD L,JR E D S.The next generation of hydrate prediction IV :A comparison of available hydrate prediction programs [J].Fluid Phase Equilibria,2004,216(2):257-270.
[7] SLOAN E D,FLEYFEL F.A molecular mechanism for gas hydrate nucleation from ice [J].AIChE Journal,1991,37(9):1281-1292.
[8] YOUSIF M H,ABASS H H,SELIM M S,et al.Experimental and theoretical investigation of methane-gas-hydrate dissociation in porous media [J].SPE Reservoir Engineering,1991,6(1):69-76.
[9] ENGLEZOS P,KALOGERAKIS N,DHOLABHAI P D,et al.Kinetics of gas hydrate formation from mixtures of methane and ethane [J].Chemical Engineering Science,1987,42(11):2659-2666.
[10] GRAAUW D E,RUTTEN J J.The mechanism and the rate of hydrate formation [C].Proceedings 3rd International Symposium on Fresh Water From The Sea,Athens,1970.
[11] BYLOV M,RASMUSSEN P.Experimental determination of refractive index of gas hydrates [J].Chemical Engineering Science,1997,52(19):3295-3301.
[12] LEKVAM K,RUOFF P.A reaction kinetic mechanism for methane hydrate formation in liquid water [J].Journal of the American Chemical Society,1993,115(19):8565-8569.