METHOD FOR RE-LIQUEFYING BOIL-OFF GAS GENERATED AT LIQUID HYDROGEN STORAGE TANK

摘要

The boil-off gas discharged from a liquid hydrogen storage tank on a liquid hydrogen transport vessel (16) is introduced into the liquid hydrogen stored within liquid hydrogen storage tanks (19, 20) disposed on the ground by passing through a boil-off gas introduction path (17). At least a portion of the boil-off gas is re-liquefied by means of the cold temperature of the liquid hydrogen. The boil-off gas that was not re-liquefied and the gasified hydrogen generated as a consequence of the liquid hydrogen within the liquid hydrogen storage tanks (19, 20) gasifying are mixed with raw material hydrogen by being supplied to the raw material hydrogen path (11) of a liquid hydrogen production device (HS) by passing through a gasified hydrogen discharge path (21). The boil-off gas and the gasified hydrogen are re-liquefied by means of the liquid hydrogen production device (HS).

主权项

1. A method of re-liquefying boil-off gas generated in a primary liquid hydrogen reservoir, the method comprising:
introducing the boil-off gas into liquid hydrogen stored in a secondary liquid hydrogen reservoir so as to liquefy at least a part of the boil-off gas by means of cryogenic heat energy of the liquid hydrogen; supplying the remaining not-liquefied part of the boil-off gas and vaporized hydrogen gas generated in said secondary liquid hydrogen reservoir, to a liquid hydrogen producing unit of a liquid hydrogen producing apparatus for producing the liquid hydrogen from gaseous hydrogen, said liquid hydrogen producing apparatus including a refrigeration cycle unit in which circulating hydrogen flows as a refrigerant, in addition to said liquid hydrogen producing unit; and
liquefying the remaining not-liquefied part of the boil-off gas and the vaporized hydrogen gas by means of the liquid hydrogen producing apparatus.