Cryogenic storage system for liquefied gas - uses cooling effect of evaporation of small quantity of liquid to control pressure level in thermally insulated vessel

摘要

A thermally insulated vessel is used for storing a liquified gas at very low temperature with the liquid phase in equilibrium with the gaseous phase. Due to unavoidable evaporation the pressure in the vessel tends to rise. This pressure rise causes a valve to open so that liquid flows into a pipe and through an expansion valve into an evaporator. The evaporation of the liquid phase in the evaporator cools the gaseous phase so that the pressure in the vessel drops and first valve recloses with a minimum loss of stored gas.