Dissociation of Methane Hydrate by Hot Brine

Abstract

Natural gas hydrate has been regarded as a potentially unconventional natural gas resource. It is widely distributed in the world. Many methods are proposed to dissociate hydrate, among which heat injection is one of the most effective ones. So, the investigation of production performance under different heat injection modes provides theoretical basis for actual hydrate production. An experimental study on hydrate dissociation and gas production behavior by hot brine injection was conducted with a self-designed 2D sand-packed system. Two patterns of heat injection (continuous heat injection and intermittent heat injection) are studied and the gas production, water production, and temperature variation are analyzed. Results show that the gas produced by continuous heat injection is notably more than that by intermittent heat injection; with the same heat injected, the temperature variation of continues heat injection is larger than that of intermittent heat injection; during the process of heat injection, the water production rate is slightly larger than that of water injection, which is mainly influenced by water injection rate, heat injection patterns and water production from hydrate dissociation. Under the conditions of experiment, the result of continuous heat injection is superior than that of intermittent heat injection.