Indexed by:会议论文

Date of Publication:2019-01-01

Included Journals:CPCI-S、EI

Volume:158

Page Number:5581-5586

Key Words:Methane hydrate; hydrate exploitation; seawater flow; chemical potential difference

Abstract:Natural gas hydrates (NGHs) are regarded as a potential energy source for the future. NGHs dissociation always accompanied by the migration of water. To understand the effect of water flow migration on hydrate dissociation, the visualization studies on the variation of hydrate distribution during seawater and water flow process was carried out in this study. The different back pressure was investigated, and the influence of temperature and pressure on MH dissociation was eliminated. The experimental results showed that seawater and water flow have promotion effect on ME dissociation, where the chemical potential difference between the hydrate phase and the aqueous phase caused MH dissociation. And the rate of MH dissociation increased with decreasing backpressure. The ME dissociation time in seawater flow process was longer than the time in the water flow process. During seawater flow process, the absolute permeability appearing increased with different stages. And seawater seepage, hydrate saturation and chemical potential difference were affected by each other. (C) 2019 The Authors. Published by Elsevier Ltd.