Blow-down method of reliquefaction system for ship

A blow-down method of a reliquefaction system for ships,

• wherein boil-off generated from a liquefied gas stored in a storage tank of a ship is compressed by a compressor, cooled and reliquefied through a heat exchanger along a reliquefaction line, and returned to the storage tank after passing through a gas-liquid separator, and
• wherein the reliquefaction system is provided with a pressure compensation line extending from a downstream side of the compressor to an upside of the gas-liquid separator without passing through the heat exchanger;
• and a nitrogen blanket line along which nitrogen is supplied to the pressure compensation line, and
• wherein, in the event of a trip of the reliquefaction system, nitrogen is supplied to the pressure compensation line along the nitrogen blanket line and is delivered to the downstream side of the compressor to pass through the heat exchanger along the reliquefaction line such that the heat exchanger and the reliquefaction line are blown down to remove compressed gas, and reliquefied gas therefrom while being subjected to nitrogen (N2) purging.