Hydrate Formation Characteristics during Carbon Dioxide Flow Through Depleted Methane Hydrate Deposits

• Published in: Energy Technology
• Main Authors: Wang, Pengfei, Zhou, Hang, Ling, Zheng, Li, Yuanping
• Other Authors: National Natural Science Foundation of China
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2018
• Subjects: Methane hydrate
• Online Access: http://dx.doi.org/10.1002/ente.201700773; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fente.201700773; https://onlinelibrary.wiley.com/doi/pdf/10.1002/ente.201700773

Abstract Depleted methane hydrate (MH) reservoirs are potential sites for CO 2 storage. Hydrate formation during the CO 2 flow process in a dissociated MH sample was simulated to clarify the formation characteristics of CO 2 hydrates and their effect on CO 2 storage. Experiments included MH formation and dissociation, CO 2 injection, water‐injection and CO 2 hydrate dissociation, and liquid‐water distribution as monitored by magnetic resonance imaging (MRI). It was observed that the initial water saturation determined the hydrate saturation in the artificial sediment, and the depressurization range was the main factor influencing MH dissociation for the excess gas sample. Pressure is the key factor influencing hydrate formation during CO 2 flow. An increase of the CO 2 flow rate led to a decrease of both hydrate saturation and conversion of the injected CO 2 . The cumulative amount of injected water is not the key factor controlling CO 2 hydrate formation, but it does determine the residual water saturation.