Abstract: A method and apparatus for recovering boil-off gas from a head space of a liquid storage tank having a fluid contained therein is provided. The method can include the steps of withdrawing the boil-off gas from the storage tank and introducing said boil-off gas to a heat exchanger using a vapor flow inducer; cooling the boil-off gas in the heat exchanger by using cold energy from vaporization of liquid nitrogen to form a cooled fluid; and introducing the cooled fluid to the liquid storage tank, thereby reducing the temperature within the liquid storage tank.

Abstract: In another embodiment of the invention, a method for recovering boil-off gas from a head space of a liquid storage tank having a fluid contained therein is provided. In one embodiment, the method can include the steps of flowing the boil-off gas from the liquid storage tank to a heat exchanger by opening a valve; creating a vacuum within the heat exchanger by cooling and condensing the boil-off gas in the heat exchanger by using cold energy from vaporization of liquid nitrogen from a liquid nitrogen storage tank to form a cooled fluid; and introducing the cooled fluid to the liquid storage tank, thereby reducing the temperature within the liquid storage tank.

Abstract: A method of improving the efficiency in delivery of a cryogenic liquid to the surface of a metal body in a furnace, the method comprising the steps of delivering a liquid cryogen (10, 20) to a liquid-gas phase separator (30), allowing a gaseous cryogen (45) present in a liquid phase (40) of the liquid cryogen to separate from the liquid cryogen (40), condensing (60, 70, 80) the gaseous cryogen (45) to an additional amount of liquid cryogen (40), delivering the liquid cryogen and the additional amount of liquid cryogen (50) to the surface of a metal body in a furnace.