Experimental Evidence of Gas Hydrates Dissociation Kinetics by Shifting their Equilibrium Conditions

Abstract

The scope of this study is to define the rates under which multi-component gas hydrates contained in the pore space of a mud volcanos’ (MV) sediments may decompose in gas and water phase as a result of pressure decrease or temperature increase. Such cases can be encountered during retrieval and handling of pristine samples from the sea floor, or due to an increase of hot mud fluxes from underneath the MV area. Both of the aforementioned shifts of conditions have been studied in the bulk liquid phase of a reactor, while pressure decrease has also been studied in a piston vessel containing artificial sediment at the Centre for Gas Hydrates Research, HW University, Edinburgh.The results indicate that gas hydrate dissociation progresses much faster with pressure decrease than with temperature increase. Moreover, depressurization at temperatures above 15°C causes higher dissociation rates in comparison to that at lower temperatures.