Liquid air energy storage system and control method thereof

摘要

PPROBLEM TO BE SOLVED: To enhance the efficiency with which a liquid air energy storage system liquefies air by improving the arrangement of the system or controlling the pressure of the air. PSOLUTION: Pressure at the outlet of an air expansion valve 4 and in a liquid air storage tank 9 is kept higher than atmospheric pressure by an air pressure controller 7. An air separator 8 separates liquid air 14 from unliquefied air. After the unliquefied air is expanded in an air expansion turbine 12 until reaching pressure at which temperatures lower than the temperature of the liquid air are reached, the unliquefied air is passed through a heat exchanger 13 in the liquid air storage tank to lower the temperature of the liquid air below its saturation temperature to prevent the loss of the liquid air and enhance the liquefaction rate of air. PCOPYRIGHT: (C)2003,JPO