A method for checking the sealing of a sealed tank for storing a liquefied gas at low temperature, the tank having an inner hull and a secondary sealing membrane, a secondary space that is arranged between the inner hull and the secondary sealing membrane, a primary sealing membrane and a primary space that is arranged between the primary sealing membrane and the secondary sealing membrane is disclosed. The method has the following main steps: generating a pressure lower than the pressure of the primary space in the secondary space using a suction device, measuring the temperature of an outer surface of the inner hull, and detecting the location of a sealing defect of the secondary sealing membrane in the form of a cold spot on the outer surface of the inner hull.

Hydrogen is produced by electrolysis of water using electricity generated from a renewable energy source such as wind and/or solar radiation, compressed in a multistage compression system and consumed in at least one downstream process. Supply of hydrogen to the downstream process(es) fluctuates with demand and/or the availability of the renewable energy source. In order to accommodate such fluctuations, excess hydrogen is stored during periods when production of hydrogen exceeds that required by the downstream process(es) so that, during periods when demand exceeds production, hydrogen is removed from storage and, after suitable pressure reduction, fed to the downstream process(es) via a stage of the multistage compression system.

According to one embodiment, a CNG dispenser is provided that includes a user-actuatable button for allowing selection of a pressure to which to fill a vehicle tank with CNG, and a controller for opening a high pressure fill valve to dispense high pressure CNG into the vehicle tank while monitoring the pressure of the vehicle tank until the pressure reaches the user-selected pressure. According to another embodiment, the controller is operable in a selected one of two modes of operation. The two modes of operation include a one-pressure bank operation mode in which only the input of a high pressure fill valve is coupled to a CNG supply line, and a three-pressure bank operation mode in which the inputs of each of three fill valves are coupled to respective CNG supply lines. A graphic fuel gage may be provided on the dispenser payment terminal screen.

LNG, for use as a motor vehicle fuel, is stored in a manner that does not require massive tanks, eliminates evaporative loss and reduces refrigeration energy consumption. A Stirling cryocooler extends through a wall of a highly insulated, relatively low pressure container to its cold end located in the vapor phase above the liquid surface. The pressure or temperature of the LNG is sensed and applied to a feedback control that modulates the heat transfer rate of the Stirling cryocooler so that LNG vapor is liquefied at a rate to maintain a desired pressure and temperature within the container. Maintaining a superatmospheric pressure in the container reduces the energy consumption required for re-liquefaction of the LNG vapor. The apparatus is also usable for liquefaction of natural gas for refueling vehicles from the ubiquitous consumer level domestic gas distribution system.

The invention relates to a pneumatic emergency shutdown system for a liquefied gas supply arrangement in which liquefied gas is supplied between a first tank and a second tank. The pneumatic emergency shutdown system comprises a pneumatic emergency shutdown circuit comprising pressure medium and provided in connection with the first tank and a pneumatic emergency shutdown link provided to the pneumatic emergency shutdown circuit, said a pneumatic emergency shutdown link connecting the pneumatic emergency shutdown circuit to a pneumatic controlling system of the second tank.

A refuelling device for supplying liquefied gas is provided, including a feed system adapted to place each reservoir in fluidic through connection with a tank and including withdrawal ducts for withdrawing the liquefied gas from the reservoirs; an inlet duct for introducing the liquefied gas into the tank; a collection manifold for conveying the withdrawal ducts into the inlet duct; a pump adapted to move the liquefied gas in the feed system; and a pressure gauge to measure the inlet pressure of the liquefied gas in the pump; and a valve adapted to regulate the flow in the inlet duct according to the inlet pressure.

An apparatus includes a high-pressure tank, a controller, a valve, controlled by the controller, and a heater.

The present disclosure provides a system for managing a pressure in an underground cryogenic liquid storage tank and a method for the same. The system includes: a storage tank, which is used for containing cryogenic liquid and is buried underground; an internal pump, which is located below a liquid level of the cryogenic liquid; an evaporator, provided with an upstream end which is in communication with a discharge end of the internal pump and a downstream end which is in communication with a head space via a vapor delivery line; a control valve, which is disposed on the vapor delivery line downstream of the evaporator; and a flow limiter, which is disposed on the vapor delivery line upstream of or downstream of the control valve. The present disclosure can realize efficient pressurization to the storage tank so as to prevent collapsing of the storage tank.

A secondary indicator for a vapor recovery valve is presented. The vapor recovery valve comprises a piston and a primary indicator, the primary indicator is attached to the piston, and the piston moves linearly in relation to the actuation of the valve and moves proportionally in conjunction with the piston to provide a visual indication that the valve has actuated. The secondary indicator is mounted to the vapor recovery valve and is not attached to the primary indicator. The secondary indicator comprises a signal, a torsional spring, and a fixed pin. The secondary indicator is second class lever, the torsional spring is the effort, the fixed pin is the fulcrum, and the primary indicator is the load between the torsional spring and the fixed pin, such that the signal rotates with the linear movement of the primary indicator to multiply the effect of the primary indicator.

If an abnormality detecting unit detects an output abnormality of an internal temperature sensor, a discharge control unit obtains the amount of discharge (a limit value L of gas flow rate F) on the basis of an ambient temperature measured by an ambient temperature sensor, and controls the discharge of fuel gas on the basis of the obtained amount of discharge.