Gas hydrates: Feasibility of CO2-sequestration and related natural gas production

The formation and decomposition of CH4- and CO2- gas hydrates and the replacement of CH4 in hydrate cages by CO2 were studied under varying process conditions. The experiments were conducted in pressure vessels, operable up to 500 bar(g). CH4 hydrate was formed from gas and pure water. After fast depressurisation and renewed pressurisation of the vessel with CO2, the replacement was started and the gas phase composition was observed by gas chromatography. In case of transferring the experiments to a real natural system the first results indicate, that a replacement of CH4 in natural hydrate deposits by sequestrated CO2 from industrial processes could be feasible in principle. This could be both a promising mean to reduce the climate potential of industrial CO2 by sequestration and besides a possible way to a related natural gas production. Further investigations have to approve the results and broaden the database.