Abstract: In a new boil-off gas removal system for a liquid storage tank, boil-off vapor from the storage tank is first pressurized in the low-stage compressor. The pressurized vapor may be cooled to near cryogenic temperature in a cooler that can include a preliminary cooler and/or a high-pressure gas exchanger in which the pressurized vapor is cooled against boil-off vapor. The pressurized vapor may also be cooled by the addition of cryogenic liquid through a branch on the liquid supply line running from the low-stage pump in the storage tank. The cooled, pressurized vapor is directed to a heat exchanger where the cool, pressurized vapor travels in a path in which it is condensed against cryogenic liquid that travels in another, separate path.