Abstract

A method for recovering large volumes of hydrocarbon fuels, particularly methane (CH4), using commercially available reagents which are strongly water-soluble and soluble in liquid CO2 in the presence of liquid CO2 injected into the methane hydrate formation. The reagents which are strongly water-soluble and soluble in liquid CO2 form dilute aqueous acids that significantly increase the rate of conversion of methane hydrate into methane and CO2 hydrate, thereby allowing the natural gas to be released in a form that can then be recovered in large quantities using conventional devices. The preferred embodiment uses SO3, HCl or other strongly water soluble gas to cause the methane hydrate ice crystals to melt and form an aqueous solution. The aqueous solution contacts the methane hydrate ice on one side and liquid carbon dioxide on the other side. The system spontaneously adjusts so that the acid solution remains strong enough to melt the methane ice, but not strong enough to prevent the formation of the carbon dioxide ice at the recovery temperature and pressure. The natural gas is liberated from the hydrate and removed by conventional devices.

Other References

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