Molecular mechanisms of methane hydrate dissociation and inhibition ...

• Main Author: Bagherzadeh Hosseini, Seyyed Alireza
• Format: Text
• Language: English
• Published: University of British Columbia 2015
• Subjects: Methane hydrate; permafrost
• Online Access: https://dx.doi.org/10.14288/1.0166109; https://doi.library.ubc.ca/10.14288/1.0166109

Gas hydrates are crystalline compounds with cage-like structures formed by hydrogen-bonded water molecules hosting guest molecules such as light hydrocarbons and CO₂. They are known to: • represent a potential reserve of natural gas embedded in seabed and permafrost sediments • pose a flow assurance challenge to the oil and gas industry Molecular dynamics simulations are employed to study the processes of gas hydrate decomposition and inhibition. To mimic the porous environment of the real gas hydrate reservoirs, hydroxylated silica surfaces are included in the simulations and placed in contact with hydrate and water. Water molecules wet the silica surfaces and form a meniscus, confirming the hydrophilic properties of the hydroxylated silica surface. It is found that the silica surface alters the characteristics of the confined water up to ~6 Å away from the surface. The decomposition of methane hydrate in the presence of silica surfaces, 34 to 40 Å apart, follows a concerted behavior where layers of hydrate ...