The invention relates to a cooling system (1) comprising at least: a Stirling heat pump (2) designed to cool an inlet gas (G.sub.e) down to a cryogenic temperature so as to form a cryogenic liquid (L), a primary electric motor (3), intended to put said Stirling heat pump (2) into operation, a primary pump (4) intended to cause said cryogenic liquid (L) to circulate under pressure, and a cooling means (5) intended to cool said primary electric motor (3) with the aid of the cryogenic liquid (L) output by said primary pump (4). The invention is particularly suitable for the production of a cryogenic liquid and the applications thereof.

Plant and method for liquefying a flow of gas, comprising a cooling circuit which is provided with an upstream end which is intended to be connected to a source of pressurised gas to be liquified and a downstream end which is intended to be connected to a user member, the plant comprising, between the upstream and downstream ends, a set of members which are intended to liquefy the gas and comprise at least one exchanger for cooling the gas, and at least one expansion turbine which is mounted on a rotary axle which is supported by at least one bearing of the gas-static type, the cooling circuit comprising a pressurised gas injection conduit having an upstream end which is intended to receive pressurised gas supplied by the source and a downstream end which is connected to the bearing in order to provide support to the rotary axle, the plant comprising a conduit for recovering the gas which has been used in the bearing, the conduit for recovering the gas comprising an upstream end which is connected to the bearing and a downstream end, characterised in that the downstream end of the conduit for recovering the as is connected to the cooling circuit between the upstream and downstream ends thereof in order to recycle at that location at least a portion of the gas which has been used to support the rotary axle of the bearing with a few to liquefying said gas.

A device and a method for recovering by-product oxygen from water-electrolysis hydrogen production using a low-temperature method are provided, solving the waste problem of by-product oxygen in the green water-electrolysis hydrogen production system. The device according to the present disclosure comprises an oxygen clarifying system, a pressurizing and heat exchanging system, and a circulating gas compression and expansion refrigeration system. The recovering method according to the present disclosure comprises the following steps: first clarifying and purifying the by-product oxygen from water-electrolysis hydrogen production is to remove hydrogen, carbon monoxide, carbon dioxide, water and other impurities in the oxygen; and then, liquefying, pressurizing and heat exchanging the pure oxygen to obtain the product oxygen and liquid oxygen with required pressure. In the whole process, the cooling capacity is provided by the circulating gas expansion refrigeration system.

A process for producing liquid oxygen, including, a first operating mode, and a second operating mode. During the first operating mode, the distillation column produces a first flowrate of product liquid oxygen, and a first flow rate of liquid nitrogen product. During the second operating mode, the distillation column produces a second flowrate of product liquid oxygen, and a second flow rate of liquid nitrogen product. Wherein, the second flowrate of product liquid oxygen is greater than the first flowrate of product liquid oxygen.

A system and method for cooling an oxygen stream by heat exchange with a warming supply nitrogen stream having of a heat exchanger having at least a Zone A and a Zone B, the system having indirect heat exchange between a gaseous oxygen stream, and a high-pressure liquid nitrogen stream split into at least a first portion which passes through a Zone A, and a second portion which passes through a Zone B during a first phase of operation. And a high-pressure liquid nitrogen stream passing through Zone A, thereby producing a high-pressure nitrogen vapor stream, which passes through an expansion turbine, thereby producing an expansion turbine outlet stream which then passes through Zone B, during a second phase of operation, thereby producing a liquid oxygen stream.

The present invention provides a high efficiency prime mover with phase change energy storage for distributed generation and motor vehicle application. Phase change storage minimizes energy required for refrigerant liquefaction while reducing fuel consumption and emissions.

An oxygen liquefier system may be configured to defrost an oxygen line included therein. The system may include one or more sieve beds, a liquid oxygen reservoir, an oxygen line, a controller, a heating apparatus, and/or other components. The one or more sieve beds are configured to extract oxygen from air obtained from an ambient environment. The liquid oxygen reservoir is configured to store oxygen extracted at the one or more sieve beds that has been liquefied. The oxygen line is configured to provide fluid communication between the one or more sieve beds and the liquid oxygen reservoir. The controller is configured to detect a blockage caused by frozen liquid within the oxygen line based on a liquid oxygen production rate. The heating apparatus is configured to defrost the oxygen line to melt frozen liquid within the oxygen line responsive to the detection of the blockage.

A Dewar system is configured to liquefy a flow of fluid, and to store the liquefied fluid. The Dewar system is disposed within a single, portable housing. Disposing the components of the Dewar system within the single housing enables liquefied fluid to be transferred between a heat exchange assembly configured to liquefy fluid and a storage assembly configured to store liquefied fluid in an enhanced manner. In one embodiment, the flow of fluid liquefied and stored by the Dewar system is oxygen (e.g., purified oxygen), nitrogen, and/or some other fluid.

A system for preparing subcooled liquid oxygen based on mixing of liquid oxygen and liquid nitrogen and then vacuum-pumping, including atmospheric-pressure saturated liquid nitrogen and oxygen tanks. An inlet of the liquid nitrogen tank communicates with pressurized gas, and an outlet is connected to an inlet a of a secondary subcooler. An inlet of the liquid oxygen tank communicates with the pressurized gas, and a first outlet is connected to an inlet b of the secondary subcooler. An outlet c of the secondary subcooler is connected to an inlet d of a primary subcooler. An outlet e of the primary subcooler is connected to a pumping-out device through a rewarming device. A second outlet of the liquid oxygen tank is connected to an inlet n of the primary subcooler. An outlet o of the primary subcooler is connected to an inlet r of the secondary subcooler.

A heat exchanger 1 comprises a shell 2 which has in an interior thereof a heat exchange chamber 20 in which a gas to be cooled or an intermediate medium is filled, and performs heat exchange directly or indirectly between liquid hydrogen and the gas to be cooled, in the interior of the heat exchange chamber 20; a tray 23 which is provided in the interior of the heat exchange chamber 20 and receives a liquefied gas and a deposited substance F which are generated by the heat exchange in the interior of the heat exchange chamber 20; and a liquid discharge mechanism (flashboard 22, drain port 25, and drain pipe 26) which discharges the liquefied gas from the tray 23 in a state in which the deposited substance F is left in the tray 23.