Liquefied hydrogen facility and method for operating same

A method for operating a liquefied hydrogen facility that includes:

• a liquefier that liquefies a hydrogen gas to generate liquefied hydrogen;
• a raw material feed line that guides a raw material hydrogen gas from a raw material feed source to the liquefier;
• a storage tank that stores the liquefied hydrogen generated by the liquefier;
• a reflux line that guides to the liquefier each of a return gas that is a hydrogen gas returned from a carrier along with cargo handling for transferring the liquefied hydrogen from the storage tank to the carrier and a boil-off gas generated by evaporation of the liquefied hydrogen in the storage tank;
• a first valve provided on the raw material feed line;
• and a second valve provided on the reflux line, the method comprising:
• determining which phase the liquefied hydrogen facility is in, a cargo handling phase in which cargo handling is performed or a normal phase in which the cargo handling is not performed;
• controlling, when the liquefied hydrogen facility is determined to be in the cargo handling phase, an opening degree of the second valve in a direction in which a fluctuation in an inlet pressure of the liquefier is suppressed;
• and
• controlling, when the liquefied hydrogen facility is determined to be in the normal phase, an opening degree of the first valve in a direction in which the fluctuation in the inlet pressure of the liquefier is suppressed.