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 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; 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; and a third decompressing device which is for expanding a part of the first fluid which has been cooled by means of the boil-off gas heat exchanger (hereafter referred to as a third fluid) and sending same back to the boil-off gas heat exchanger, wherein the boil-off gas heat exchanger uses the boil-off gas being discharged from the storage tank and the third fluid as a refrigerant and 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.