An apparatus, system and method for capture, utilization and sendout of latent heat in boil off gas (BOG) onboard a cryogenic storage vessel is described. A liquefied gas vessel comprises a cryogenic cargo tank onboard a liquefied gas vessel, the cargo tank comprising a liquefied gas and a BOG, a latent heat exchanger fluidly coupled to a stream of the liquefied gas and a stream of the BOG, wherein the latent heat exchanger transfers a heat between the BOG stream and the liquefied gas stream to produce a condensed BOG, means for combining the condensed BOG and the liquefied gas stream to obtain a combined stream, the means for combining the condensed BOG and the liquefied gas stream fluidly coupled to the latent heat exchanger, and a liquefied gas regasifier onboard the vessel and fluidly coupled to the combined stream, wherein the liquefied gas regasifier regasifies the combined stream.

Disclosed herein is a BOG reliquefaction method for LNG ships. The BOG reliquefaction method for LNG ships includes: 1) compressing BOG; 2) cooling the BOG compressed in Step 1) through heat exchange between the compressed BOG and a refrigerant using a heat exchanger; 3) expanding the BOG cooled in Step 2); and 4) stably maintaining reliquefaction performance regardless of change in flow rate of the BOG compressed in Step 1) and supplied to the heat exchanger to be used as a reliquefaction target.

A fuel supply apparatus of a liquefied gas carrier includes: a compressor for compressing gas fuel into a high pressure; a compressed gas storage tank being filled with the compressed high-pressure gas fuel, for storing the gas fuel; and a decompressor for decompressing the high-pressure gas fuel drawn from the compressed gas storage tank into a pressure suitable to be used in a propulsion system, to supply fuel to the propulsion system. The gas fuel is at least one of a natural boiled-off gas which is naturally evaporated in the cargo tank, a forced boiled-off gas which is artificially evaporated, and a gas additionally supplied for the use of fuel. Further, the compressor is a multistage high-pressure compressor and the decompressor is a multistage decompressor.

A ship includes: a boil-off gas heat exchanger which heat-exchanges a compressed boil-off gas (a first fluid) by means of a boil-off gas discharged from the storage tank as a refrigerant; a compressor installed on the downstream of the boil-off gas heat exchanger and compressing a part of the boil-off gas discharged from the storage tank; first and second extra compressors provided in parallel with the compressor on the downstream of the boil-off gas heat exchanger and compressing the other part of the boil-off gas discharged from the storage tank; a refrigerant heat exchanger which additionally cools the first fluid cooled by means of the boil-off gas heat exchanger; a refrigerant decompressing device which expands a second fluid, which has been sent to the refrigerant heat exchanger and cooled by means of the refrigerant heat exchanger, and then sending the expanded second fluid back to the refrigerant heat exchanger.

An LNG carrier which uses natural gas generated by vaporization of LNG as propulsive fuel and including cargo tank, spray apparatus, and carrier communication device; land-based equipment including land-based communication device and processing device; processing device including: first vapor quantity estimating section which estimates total quantity of natural vapor generated from the LNG remaining in the cargo tank in a case where the LNG carrier is traveling on planned ballast course, based on sea weather data; a second vapor quantity estimating section which estimates a total quantity of spray vapor generated by performing spraying operations in a case where the LNG carrier is traveling on planned ballast course, based on the sea weather data; and heel quantity calculating section which calculates required heel quantity, by summing the total quantity of natural vapor and spray vapor, and the land-based communication device transmits the required heel quantity to the carrier communication device.)

An apparatus, system and method for capture, utilization and sendout of latent heat in boil off gas (BOG) onboard a cryogenic storage vessel is described. A liquefied gas vessel comprises a cryogenic cargo tank onboard a liquefied gas vessel, the cargo tank comprising a liquefied gas and a BOG, a latent heat exchanger fluidly coupled to a stream of the liquefied gas and a stream of the BOG, wherein the latent heat exchanger transfers a heat between the BOG stream and the liquefied gas stream to produce a condensed BOG, means for combining the condensed BOG and the liquefied gas stream to obtain a combined stream, the means for combining the condensed BOG and the liquefied gas stream fluidly coupled to the latent heat exchanger, and a liquefied gas regasifier onboard the vessel and fluidly coupled to the combined stream, wherein the liquefied gas regasifier regasifies the combined stream.

A gas processing system according to an embodiment of the present invention includes a heater which is configured to increase a temperature of liquefied gas compulsorily vaporized by a forcing vaporizer before the liquefied gas is joined with Boil Off Gas (BOG) compressed by a BOG compressor.

An apparatus, system and method for capture, utilization and sendout of latent heat in boil off gas (BOG) onboard a cryogenic storage vessel is described. A liquefied gas vessel comprises a cryogenic cargo tank onboard a liquefied gas vessel, the cargo tank comprising a liquefied gas and a BOG, a latent heat exchanger fluidly coupled to a stream of the liquefied gas and a stream of the BOG, wherein the latent heat exchanger transfers a heat between the BOG stream and the liquefied gas stream to produce a condensed BOG, means for combining the condensed BOG and the liquefied gas stream to obtain a combined stream, the means for combining the condensed BOG and the liquefied gas stream fluidly coupled to the latent heat exchanger, and a liquefied gas regasifier onboard the vessel and fluidly coupled to the combined stream, wherein the liquefied gas regasifier regasifies the combined stream.

The present disclosure relates to a natural gas hydrate tank container loading system for transporting natural gas hydrate, and the present disclosure provides a natural gas hydrate tank container loading system, enabling self-powered power generation and boil-off (BOG) gas treatment, includes: a refrigerator for inhibiting the generation of boil-off gas which naturally generates in a natural gas hydrate tank container during transportation; and a solar cell, a battery, and a generator, which operates by means of the boil-off gas, for supplying electric power to the refrigerator, thereby ensuring a generation capacity sufficient to operate the refrigerator by means of the solar cell, the generator, and the battery, and thus always maintaining a stable phase equilibrium (self-preservation) in the natural gas hydrate tank container even during long-distance transportation and solving problems of fire, environmental pollution, or the like which occur when the boil-off gas (BOG) is discharged to the outside.

A method for handling a vent gas mixture originating from a fuel system and comprising fuel vapours and inert gas. The method involves: directing the vent gas mixture from the fuel system to a condenser, the condenser condensing at least a majority of the fuel vapours into liquid fuel such that the vent gas mixture comprises liquid fuel and inert gas, separating the liquid fuel and the inert gas of the vent gas mixture from the condenser in a vapour-liquid separator, and selectively directing the liquid fuel from the separator to a boiler system, when the boiler system is in a hot condition and is ready to receive and combust the liquid fuel of the vent gas mixture, or storing the liquid fuel in the separator and/or in a separate storage tank until the boiler system is in the hot condition and is ready to receive/combust the liquid fuel.