28th International Ocean and Polar Engineering Conference, ISOPE 2018, pp.234 - 238
Abstract
In this study, the influence of CO2 injection into various gas hydrates (CH4 hydrate for sI, CH4 + C3H8 hydrate for sII, and CH4 + methylcyclopentane (MCP) hydrate for sH) was investigated to reveal the replacement mechanism. The thermal properties were measured using HP μ-DSC. The structure of gas hydrates was analyzed using PXRD. For sI hydrate, there was no structural transformation after replacement even though the hydrate equilibrium was shifted to stable regions. For sII hydrate, PXRD analysis showed partial structural transition during replacement. For sH hydrate, the significant heat exchange during replacement indicated dissociation and reformation of hydrate.