Embodiments of systems and methods for transporting fuel and carbon dioxide (CO.sub.2) in a dual-fluid vessel thereby minimizing transportation between locations are disclosed. In an embodiment, the dual-fluid vessel has an outer shell with two or more inner compartments, positioned within the outer shell, including a first inner compartment for storing CO.sub.2 and a second inner compartment for storing fuel. The dual-fluid vessel may connect or attach to a transportation vehicle to thereby allow transportation of the fuel and CO.sub.2. Insulation may provide temperature regulation for the fuel and CO.sub.2 when positioned in the respective first and second inner compartments. One or more ports having an opening in and through the outer shell and a fluid pathway to one or more of the first inner compartment or the second inner compartment may provide fluid communication through the opening and fluid pathway for loading/offloading the fuel and/or CO.sub.2.

A system and method and apparatus includes a cylinder having corresponding end caps and wherein each end cap includes at least one corresponding gas port and a floating piston disposed within the cylinder, the floating piston including at least one seal, the at least one seal being operative to form a seal between the floating piston and an inner surface of the cylinder.

A container may be supplied with an incompressible fluid. For example, the container may be partially or completely prefilled with the incompressible fluid. The container may be supplied with a flow of compressible gas via a first valve. The first valve may regulate the flow of the compressible gas supplied to the container based on a pressure setting of the first valve. A second valve may release the incompressible fluid from the container as the container is filled with the compressible gas and in response to a pressure of the container being greater than a pressure setting of the second valve. The pressure setting of the first valve may be greater than the pressure setting of the second valve.

A constant-pressure storage unit and a method for operating a constant-pressure storage unit, for storing and dispensing hydrogen under constant pressure are disclosed. The constant-pressure storage unit has at least one constant-pressure store, which is divided into two regions by a movable separating piston, at least one liquid pump for conveying a liquid, and at least one liquid store, wherein a measuring device measures the liquid level in the liquid store and sends a signal to the liquid pump by means of a control unit. In this way, the liquid pump can be stopped in time when the constant-pressure storage unit is empty.

A pressure-compensated rupture disk assembly and method for subsea protection of a pressure vessel. The assembly and method incorporate a piston device, a dynamic piston seal configured to move the piston device when a predetermined pressure is reached; and a rupture disk adjacent the piston device, the rupture disk having a first pressure on a piston side and a second pressure on a second side, the rupture disk being configured to open when a predetermined pressure is exceeded.

A pressure vessel disclosed herein comprises a chamber. The pressure vessel also comprises a passageway extending from an exterior wall of the pressure vessel to the chamber. A one-way valve is disposed in the passageway. The one-way valve is normally closed and is in fluid communication with the chamber. A plug is disposed within the passageway and is accessible from outside of the pressure vessel.

A device for transferring liquid helium into a usage helium tank of a usage cryostat includes a reservoir cryostat with a vacuum-insulated reservoir helium tank configured to store liquid helium available for filling the usage helium tank, a supply line for liquid helium, and a gaseous helium return line. The supply line proceeds from the vacuum-insulated reservoir helium tank and is connected to the usage helium tank. The gaseous helium return line leads into the vacuum-insulated reservoir helium tank and is connected to the usage helium tank. The device further includes a conveying device configured to convey liquid helium from the vacuum-insulated reservoir helium tank through the supply line into the usage helium tank and further configured to convey gaseous helium from the usage helium tank through the return line into the vacuum-insulated reservoir helium tank.

A pressure vessel includes: a barrel part disposed in a predefined square area and having a diameter corresponding to a length of one side of the square area; a first nozzle member disposed at one end of the barrel part; a second nozzle member disposed at an opposite end of the barrel part; and clamp rings disposed in the square area, positioned outside the barrel part, and configured to lock the first and second nozzle members to the barrel part, thereby improving spatial utilization and a degree of design freedom.

A container may be supplied with an incompressible fluid. For example, the container may be partially or completely prefilled with the incompressible fluid. The container may be supplied with a flow of compressible gas via a first valve. The first valve may regulate the flow of the compressible gas supplied to the container based on a pressure setting of the first valve. A second valve may release the incompressible fluid from the container as the container is filled with the compressible gas and in response to a pressure of the container being greater than a pressure setting of the second valve. The pressure setting of the first valve may be greater than the pressure setting of the second valve.

Disclosed embodiments include apparatuses for compressing dry ice. In an illustrative embodiment, an apparatus for compressing dry ice includes: a hollow cylinder; a post disposed coaxially in the cylinder; a piston defining an opening therein and being slidably disposed in the cylinder, the opening slidably receiving the post therein; a biasing device operatively coupled to the piston; an inlet port connectable to a source of liquid carbon dioxide and configured to introduce liquid carbon dioxide into the cylinder, the inlet port being further configured to expand liquid carbon dioxide to dry ice and to gaseous carbon dioxide; and an openably closable lid positionable among a first closed position configured to vent gaseous carbon dioxide from the cylinder, a second closed position configured to leakably close the cylinder to permit carbon dioxide flakes to be compressed in the cylinder, and an open position.