An integrated model for CO2 hydrate formation in sand sediments for sub-seabed CO2 storage. (September 2016)

• Record Type: Journal Article
• Authors: Yu, Tao; Sato, Toru; Nakashima, Takuya; Inui, Masayuki; Oyama, Hiroyuki
• Is Part Of: International journal of greenhouse gas control. Volume 52(2016:Sep.)
• Page Start: 250
• Page End: 269
• Publication Date: 2016-09
• Subjects: CO2 capture and storage -- Sub-seabed CO2 storage -- CO2 hydrate -- Hydrate formation -- Sand sediment -- Gas-liquid two-phase flow; Greenhouse gases -- Environmental aspects -- Periodicals; Air -- Purification -- Technological innovations -- Periodicals; Gaz à effet de serre -- Périodiques; Gaz à effet de serre -- Réduction -- Périodiques; Air -- Purification -- Technological innovations; Greenhouse gases -- Environmental aspects; Periodicals; 363.73874605
• DOI: 10.1016/j.ijggc.2016.07.009
• Languages: English
• ISSNs: 1750-5836

Abstract

Highlights: Subsea CO2 storage using gas hydrate is of great interest due to low risk of leakage. A new model for CO2 hydrate formation is proposed to figure out its morphologies in the sand sediment. Numerical simulations of CO2 hydrate formation in the sand sediment are conducted. CO2 hydrate formation behind the gas front results in the permeability reduction. Abstract: CO2 capture and storage has been considered to be one of the most effective strategies against global warming, among which CO2 storage in deep saline aquifers using the sealing effect of gas hydrate and CO2 storage in the sub-seabed sand sediment in the form of gas hydrate are of great interest nowadays, due to the large capacity of CO2 storage in sub-seabed sand sediments and low risk of CO2 leakage. To access those two options, an integrated model for CO2 hydrate formation, which includes hydrate formation rates on the gas front, on the hydrate film behind the gas front, and on the surface of the sand particles behind the gas front, is proposed in this study to predict hydrate formation morphologies in the sand sediment under the condition of gas-liquid two-phase flow. Then, numerical simulations of CO2 hydrate formation in the sand sediment are conducted, and unknown parameters in the models are determined by comparing the simulation results with experimental data. The simulation results indicate that CO2 hydrate formation on the hydrate film behind the gas front makes a great contribution to CO2 hydrate saturation near the boundary, occupies the pore space of the sand sediment, and results in the permeability reduction and the blockage of the gas flow.