A ship including a storage tank for storing a liquefied gas includes: a boil-off gas (BOG) heat exchanger installed on a downstream of a storage tank and heat-exchanges a compressed BOG (a first fluid) by a BOG discharged from the storage tank as a refrigerant, to cool the BOG; a compressor installed on a downstream of the BOG heat exchanger and compresses a part of the BOG discharged from the storage tank; an extra compressor installed on a downstream of the BOG heat exchanger and in parallel with the compressor and compresses the other part of the BOG discharged from the storage tank; a refrigerant heat exchanger which additionally cools the first fluid cooled by the BOG heat exchanger; and a refrigerant decompressing device which expands a second fluid sent to the refrigerant heat exchanger, and then sends the second fluid back to the refrigerant heat exchanger.

A system for maintaining a substantially constant pressure within an ullage space of a cryogenic storage tank is provided. The system includes a compressor configured to receive fuel gas from the cryogenic storage tank, and compress the fuel gas to produce heated fuel gas. The system further includes a heat exchanger in flow communication with the compressor and configured to cool the heated fuel gas to produce cooled fuel gas, and a turbine in flow communication with the heat exchanger and configured to expand the cooled fuel gas to produce a gas and liquid mixture having a predetermined liquid to gas ratio, and discharge the gas and liquid mixture into the cryogenic storage tank.

An installation and method for storing liquefied gas, comprising a plurality of separate storage tanks each configured to contain liquefied gas, comprising a cooling circuit provided with a refrigeration device, a withdrawal pipe and a plurality of first injection pipes towards each of the tanks in order to cool the withdrawn fluid flow, the tanks comprising a degassing line, the installation comprising a set of controlled valves situated at least in the cooling circuit, wherein the first tank contains liquid and at least one other tank is empty, containing essentially boil-off gas, that is to say containing little or no liquid, wherein there is cooling of the fluid contained in the first tank, re-injection into the first tank, injection of liquid cooled by the refrigeration device into at least one other empty tank and transfer of boil-off gas generated in the or the other tanks to the first tank

Systems and methods for controlling the temperature and pressure of a cryogenic liquid methane storage unit are provided. The disclosed systems and methods generate methane gas from a reservoir of liquid methane stored within the methane storage unit, vent the methane gas through one or more outlet valves connected to the methane storage unit, and generate electric power using the vented methane gas. The generated electric power can then be used to initiating a cooling cycle, which reduces the temperature of said reservoir of liquid methane and reduces the pressure in said methane storage unit. Micro anaerobic digesters and methane storage units may be configured in a networked environment with a central controller that monitors remote units.

A vapor pressure regulation system includes a vessel including a vessel wall that defines an enclosure, and a temperature adjustment mechanism coupled to the vessel. A heat transfer between the temperature adjustment mechanism and the vessel is adjusted based on at least a vapor pressure within the vessel to facilitate regulating the vapor pressure within the vessel.

A condensation system for a reservoir, which stores fuel cryogenically, is disclosed. A portion of the fuel exists as a boil-off gas with a first vapor quality. The condensation system includes an absorption unit coupled to the reservoir and is configured to receive and mix the boil-off gas with a refrigerant, forming a liquid solution. A distillation unit is coupled to the absorption unit to receive the liquid solution at a supplemented pressure, and is configured to separate the fuel to a gaseous state from the liquid solution. Further, a cooling circuit is configured to receive the fuel in the gaseous state from the distillation unit at the supplemented pressure and a supplemented temperature, and deliver the fuel to the reservoir at a lower pressure and a temperature, with a vapor quality lower than the first vapor quality.

Method for delivering liquefied gas, especially hydrogen, by means of at least one mobile storage facility, especially a storage facility transported by lorry, comprising a step of filling the mobile storage facility with liquefied gas at a source plant, the mobile storage facility containing, after filling, liquefied gas and a fraction of the vaporized gas, the method comprising a movement of the mobile storage facility from the source plant to a receiving station and a transfer of liquefied gas from the mobile storage facility to the receiving station, characterized in that it comprises a step of interim cooling of the liquefied gas contained in the mobile storage facility between the source plant and the receiving station by means of a cooling device comprising a liquefied gas tank and a refrigerating element.

Systems and methods for controlling the temperature and pressure of a cryogenic liquid methane storage unit are provided. The disclosed systems and methods generate methane gas from a reservoir of liquid methane stored within the methane storage unit, vent the methane gas through one or more outlet valves connected to the methane storage unit, and generate electric power using the vented methane gas. The generated electric power can then be used to initiating a cooling cycle, which reduces the temperature of said reservoir of liquid methane and reduces the pressure in said methane storage unit. Micro anaerobic digesters and methane storage units may be configured in a networked environment with a central controller that monitors remote units.

A device and a method for keeping a liquefied gas store cold having a cryogenic refrigerator, a subcooling circuit having an aspiration end intended to be seated in a liquefied gas store, a heat exchanger exchanging heat between the aspirated subcooling circuit and the refrigerator, the subcooling circuit having at least one injection end configured to inject the fluid cooled in the heat exchanger into the store, the device further including a boil-off gas recovery pipe having an upstream end intended to be connected to the store to recover the boil-off gas, the recovery pipe comprising a downstream end intended to be connected to a consumer, the device having a bypass pipe and a set of valves configured to enable boil-off gas to be transferred from the recovery pipe to the subcooling circuit.

The present invention relates to a liquefied gas treatment system in which a nitrogen control unit controls a content of nitrogen in a boil-off gas or a flash gas when a ratio of a nitrogen component of the flash gas is equal to or greater than a preset value. The efficiency of a boil-off gas compressor can be improved and the system can be stabilized by means of the nitrogen control unit.