Gas hydrate cold storage using direct-contact heat transfer of liquid-vapor phase change and natural circulation of refrigerant in closed vessel

Abstract

The proposed cold storage method using heat transfers of direct-contact liquid-vapor phase change between the heat transfer medium and water in a closed vessel, whose effectiveness for a small-size vessel was confirmed in the previous report, was adopted and expanded for the actual size of a storage vessel. HCFC142b and water or water solution of a surface active agent were used as the heat transfer medium and cold storage material, respectively. The chemical reaction (hydration) heat of the HCFC142b and water was utilized. As a result, it was confirmed by the experiment using large-scale apparatus that efficient cold storage and release was achieved. In particular, for the water solution of a surface active agent, a high solid packing factor and high rate of cold storage were maintained even for the thickest storage material layer.