A small scale natural gas liquefaction plant is integrated with an LNG loading facility in which natural gas is liquefied using a multi-stage gas expansion cycle. LNG is then loaded onto an LNG truck or other LNG transport vehicle at the loading facility using a differential pressure control system that uses compressed boil off gas as a motive force to move the LNG from the LNG storage tank to the LNG truck so as to avoid the use of an LNG pump and associated equipment as well as to avoid venting of boil off vapors into the environment.

A pressure vessel refueling system enables fast refueling of Compressed Natural Gas (CNG) fuel tanks. The system includes a pressure vessel having a gas inlet/outlet port and a liquid inlet/outlet port; a first liquid at least partially filling the pressure vessel; a liquid layer of a second liquid floating on top of the first liquid, wherein the second liquid is immiscible with the first liquid; a gas at least partially filling the pressure vessel above the liquid layer of the second liquid, the gas in fluid communication with the gas inlet/outlet; and a pump in fluid communication with the liquid inlet/outlet of the pressure vessel, whereby the first liquid can be pumped or returned to/from storage into or out of the pressure vessel.

A method is provided for refueling a cryogenic pressure vessel of a motor vehicle. The motor vehicle has: a) a cryogenic pressure vessel having an internal vessel which stores a fluid, an external vessel and heat insulation which is arranged between the internal vessel and the external vessel, at least in certain areas; and b) a controller, wherein the controller is designed to interrupt refueling of the motor vehicle if, in the case of damaged thermal insulation, a lower fluid density limiting value for the fluid in the internal vessel is exceeded. The lower fluid density limiting value is lower than an upper fluid density limiting value for the fluid in the internal vessel in the case of refueling of the internal vessel with intact thermal insulation.

A BOG reliquefaction system includes: a compressor; a heat exchanger cooling the BOG compressed by the compressor through heat exchange using BOG not compressed by the compressor; a pressure reducer disposed downstream of the heat exchanger and reducing a pressure of fluid cooled by the heat exchanger; and a combination of a first temperature sensor disposed upstream of a cold fluid channel of the heat exchanger and a fourth temperature sensor disposed downstream of a hot fluid channel of the heat exchanger, combination of a second temperature sensor disposed downstream of the cold fluid channel of the heat exchanger and a third temperature sensor disposed upstream of the hot fluid channel of the heat exchanger, or combination of a first pressure sensor disposed upstream of the hot fluid channel of the heat exchanger and a second pressure sensor disposed downstream of the hot fluid channel of the heat exchanger.

The design and structure of an integrated MEMS mass flow meter with a conventional pressure regulator for fuel gas cylinder enabled with wireless data communication is exhibited in this disclosure. The battery-powered MEMS mass flow meter integrated with a pressure sensor, a temperature sensor and a Bluetooth as well as one long-distance communication devices is packed by the conventional fuel gas cylinder mechanical pressure regulator to form a new integrated apparatus. Such an apparatus can digitize the fuel gas consumption supplied by a cylinder to provide such consumption information to the fuel gas cylinder suppliers or the third-party service providers, and will also timely stream the cylinder status such as leakage and location data which will significantly improve the efficiency of fuel gas usage, control, and its supply logistics.

A methane retention system is provided for reducing the amount of natural gas that is vented into the atmosphere during depressurization and maintenance of a natural gas compressor unit. Also provided are a method of depressurizing a natural gas compressor unit and a natural gas system, both of which include the methane retention system.

Disclosed is a method of monitoring pressure in a fire suppression system of an aircraft, the method providing: receiving a first pressure-vessel measured pressure from a first pressure-vessel pressure transducer connected to a first pressure-vessel; receiving a second pressure-vessel measured temperature from a second pressure-vessel temperature sensor connected to a second pressure-vessel; calculating a first pressure-vessel estimated pressure from the second pressure-vessel measured temperature; comparing the first pressure-vessel measured pressure With the first pressure-vessel estimated pressure; and providing a depressurization alert when a difference between the first pressure-vessel measured pressure and the first pressure-vessel estimated pressure is greater than a threshold thereby avoiding unscheduled aircraft downtime due to an erroneous or missing temperature measurement in the first pressure-vessel.

A waste hydrogen recovery device of an evaluation device of a hydrogen refueling station includes: a buffer container connected to a discharge pipeline of the evaluation device; a flow path switching valve installed at a hydrogen supply side of the hydrogen refueling station and installed to selectively form a flow path flowing hydrogen from one of a hydrogen supply source or the buffer container into the hydrogen refueling station; and a controller provided to control a tank protection valve installed between an inflow pipeline and a discharge pipeline of the evaluation device, and the controller further provided to control a hydrogen tank, a discharge valve installed on the discharge pipeline, the flow path switching valve, and a compressor of the hydrogen refueling station.

A boil-off gas supply device is provided with: a storage tank configured to store a liquefied gas; a first compression mechanism configured to suck in the boil-off gas of the liquefied gas stored in the storage tank and compress the sucked boil-off gas; a second compression mechanism configured to compress the boil-off gas after being compressed by the first compression mechanism; a discharge path in which the boil-off gas discharged from the second compression mechanism flows; a first drive source configured to drive the first compression mechanism; and a second drive source that is different from the first drive source and configured to drive the second compression mechanism.

The present invention pertains to a method for filling a transport tank with a product medium in a liquid state in a gas liquefaction plant, comprising a step of supplying the product medium in the liquid state from a storage tank (18) of the gas liquefaction plant to the transport tank. The method is characterized in that it further comprises a step of discharging the product medium in a gaseous state from the transport tank into the storage tank (18).