SHIP

摘要

Disclosed is a ship comprising a storage tank for storing a liquefied gas. A ship comprises: a boil-off gas heat exchanger which is provided downstream of a storage tank and is for heat exchanging a compressed boil-off gas (hereafter referred to as "a first fluid") by means of a boil-off gas discharged from the storage tank as a refrigerant, thereby cooling same; a compressor which is provided downstream of the boil-off gas heat exchanger and is for compressing a part of the boil-off gas discharged from the storage tank; an extra compressor which is provided downstream of the boil-off gas heat exchanger and parallel with the compressor and is for compressing the other part of the boil-off gas discharged from the storage tank; a propulsion compressor which is provided upstream of the boil-off gas heat exchanger and is for compressing the first flow supplied to the boil-off gas heat exchanger; a refrigerant heat exchanger which is for additionally cooling the first fluid which has been cooled by means of the boil-off gas heat exchanger; a refrigerant decompressing device which is for expanding a second fluid, which has been sent to the refrigerant heat exchanger (a fluid sent to the refrigerant heat exchanger hereafter being referred to as "a second fluid") and cooled by means of the refrigerant heat exchanger, and then sending same back to the refrigerant heat exchanger; and a first decompressing device which is for expanding the first fluid that has been cooled by means of the boil-off gas heat exchanger and refrigerant heat exchanger, wherein the refrigerant heat exchanger heat exchanges and cools both the first fluid and second fluid by means of the boil-off gas, which has passed the refrigerant decompressing device, as a refrigerant, wherein the first fluid is either the boil-off gas which has been compressed by means of the compressor or a confluent flow of the boil-off gas compressed by means of the compressor and the boil-off gas compressed by means of the extra compressor, and the second fluid is either the boil-off gas which has been compressed by means of the extra compressor or a confluent flow of the boil-off gas compressed by means of the compressor and the boil-off gas compressed by means of the extra compressor.