BOG RE-LIQUEFACTION APPARATUS AND METHOD FOR VESSEL

摘要

The present invention discloses a reliquefaction apparatus which uses the boil-off gas as a cooling fluid to reliquefy a boil-off gas generated from a liquefied natural gas storage tank installed on a vessel. An apparatus of reliquefying a boil-off gas for a vessel according to the present invention comprises: a plurality of compressors which compress a boil-off gas exhausted from the storage tank in multiple stages; a plurality of coolers each of which is installed at the rear end of the plurality of compressors to lower temperature of the boil-off gas; a self-heat exchanger which heat exchanges the boil-off gas compressed by the plurality of compressors and the boil-off gas exhausted from the storage tank; a decompression device which lowers pressure of the compressed boil-off gas passing through the self-heat exchanger; a gas-liquid separator which separates a boil-off gas reliquefied while passing through the decompression device and a boil-off gas in a gas state; and a bypass line which directly sends the boil-off gas to the storage tank by detouring a boil-off gas passing through the self-heat exchanger and the decompression device.