A check valve assembly includes a valve, cam and arm with float rotatably connected to the valve for insertion into a fluid storage container for filling of the container without overfilling. The valve includes a channel of narrowing diameter and restricting member movably retained within the channel. One end of the restricting member rides along the cam profile as the arm rotates the cam with the changing fluid levels. When the fluid reaches maximum fill level, the restricting member contacting the cam drops into the cam valley, driving the restricting member head into engagement with the channel neck walls and automatically sealing off the valve. First and second biasing members are disposed in the channel, preferably around the stem, and collectively provide counter force sufficient to overcome the frictional forces of the seal to open valve and move the restricting member upward.

An amount Y of liquid hydrogen that has passed through a first valve and has been volatilized during a predetermined time after first and second valves are opened is calculated by using a pressure P0 in an internal space of a liquid hydrogen tank measured before the two valves are opened, a pressure P1 in the internal space measured after the lapse of the predetermined time since the two valves are opened, and an amount X of the gaseous hydrogen that has passed through the second valve during the predetermined time. A fluid level H of the liquid hydrogen in the liquid hydrogen tank after the lapse of the predetermined time since the two valves are opened is calculated by using a expression showing a relationship between the H and an amount Y1 of the liquid hydrogen that passes through the first valve and drops therefrom, and the Y.

A liquid level measurement system includes a wave guide strip including a first end and a second end. The measurement system includes a sensor array positioned more proximate to the first end than the second end. The wave guide strip is configured and adapted to guide waves emitted from the sensor array. A method for determining a liquid level measurement in a fluid tank includes emitting an excitation from a transmitter of a sensor array along a wave guide strip into the fluid tank, thereby generating a plurality of guided waves. The method includes receiving at least one reflected wave with at least one receiver of the sensor array. The method includes determining a liquid level within the fluid tank by correlating at least one characteristic of the at least one reflected wave to a liquid level in the fluid tank.

A cryogenic liquid dispensing device may include a cryogenic cylinder for containing a cryogenic liquid. A dispensing pipe may be in fluid communication with the cryogenic cylinder. A dispensing valve may be configured to govern the fluid communication between the dispensing pipe and the cryogenic cylinder. A heating element may be disposed within the cryogenic cylinder, and the heating element may be configured to generate heat within the cryogenic cylinder to increase the pressure within the cryogenic cylinder. By generating heat within the cryogenic cylinder, the pressure within the cylinder may be increased and used to motivate a cryogenic fluid within the cylinder to the dispensing valve and out of the dispensing pipe. Preferably, the device may include a processing unit that may be configured to cause the heating element to generate heat within the cryogenic cylinder when a pressure reader detects a minimum pressure within the cryogenic cylinder.

A cylinder for liquefied gas that includes a withdrawal tube that prevents liquid product from the cylinder from being inadvertently dispensed to the tool downstream. The cylinder also includes a level measuring means used to determine the remaining liquid level in the cylinder. A low power level display to indicate low levels of liquid in the cylinder using a minimum of power consumption may also be included.

Some embodiments of the presently disclosed subject matter relate to a method and system for the real-time calculation of the amount of residual chemical energy in a non-refrigerated, pressurised tank containing liquefied natural gas, without a composition of the liquefied natural gas having to be determined.

In a process for vaporizing a liquid stream rich in carbon dioxide wherein a liquid first stream rich in carbon dioxide is withdrawn from a chamber containing liquid rich in carbon dioxide and gas rich in carbon dioxide, the gas being at a pressure P.sub.1, the liquid first stream is sent to a heat exchanger where it is vaporized, all the liquid from the first stream is vaporized in the heat exchanger at a pressure or several pressures greater than P.sub.1, the vaporized first stream is extracted from the heat exchanger, expanded in a first expansion valve and sent to the heat exchanger where it is heated.

The invention relates to a filling level measuring device (10) for measuring the filling level in a container (2) through the wall (9) thereof by means of ultrasound, having an ultrasonic measuring head (12), a controller (20), and a fastening device (24) by means of which the filling level measuring device (10) can be fastened to the container (2) such that the ultrasonic measuring head (12) is pressed against the wall (9) of the container (2). The invention further relates to a method of operating such a filling level measuring device (10), wherein a sampling rate is used which is situation-dependent. The invention finally relates to an assembly made up of such a filling level measuring device and at least one spacer (50) which can be attached to the lower edge of a container (2) to be provided with the filling level measuring device (10).

The invention relates to a filling level measuring device (10) for measuring the filling level in a container (2) through the wall (9) thereof by means of ultrasound, having an ultrasonic measuring head (12), a controller (20), and a fastening device (24) by means of which the filling level measuring device (10) can be fastened to the container (2) such that the ultrasonic measuring head (12) is pressed against the wall (9) of the container (2). The invention further relates to a method of operating such a filling level measuring device (10), wherein a sampling rate is used which is situation-dependent. The invention finally relates to an assembly made up of such a filling level measuring device and at least one spacer (50) which can be attached to the lower edge of a container (2) to be provided with the filling level measuring device (10).

A multi-vessel fluid storage and delivery system is disclosed which is particularly useful in systems having internal combustion engines which use gaseous fuels. The system can deliver gaseous fluids at higher flow rates than that which can be reliably achieved by vapor pressure building circuits alone, and that keeps pressure inside the storage vessel lower so that it reduces fueling time and allows for quick starts thereafter. The system is designed to store gaseous fluid in liquefied form in a plurality of storage vessels including a primary storage vessel fluidly connected to a pump apparatus and one or more server vessels which together with a control system efficiently stores a liquefied gaseous fluid and quickly delivers the fluid as a gas to an end user even when high flow rates are required. The system controls operation of the pump apparatus as a function of the measured fluid pressure, and controls the fluid pressure in a supply line according to predetermined pressure values based upon predetermined system operating conditions.