Hydrogen is liquefied through a process utilizing refrigeration from hydrogen at one, two, or three different pressures as well as a nitrogen refrigeration cycle. One or more stages of catalyst are used to convert ortho-hydrogen to para-hydrogen as the hydrogen is cooled and liquefied. Subcooled liquid hydrogen feeds the final stage of ortho-hydrogen to para-hydrogen conversion to reduce or eliminate vaporization of the hydrogen during the exothermic ortho-hydrogen to para-hydrogen conversion.

The invention relates to an installation for liquefying a cryogenic fluid, for example hydrogen, comprising a circuit for supplying fluid to be cooled that is provided with an upstream end and a downstream end connected in parallel to a plurality of cryogenic stores, a set of heat exchanger(s) in heat exchange with the supply circuit and a cooling device comprising a refrigerator with a cycle of refrigeration of a cycle gas, the installation comprising a set of liquid withdrawal ducts provided with a set of valve(s) and connecting the stores to at least one connecting end, the installation comprising a common heater connected in parallel to the plurality of cryogenic stores for fluid via a set of pressurization ducts provided with valves and configured to allow the pressurization of each of the cryogenic stores via the common heater.

The invention relates to an installation for producing liquefied gas comprising a circuit for supplying feed gas, a set of heat exchangers, a refrigerator for cooling some or all of the set of heat exchangers, the supply circuit comprising, between the set of heat exchangers and the downstream end thereof, a final expansion turbine for expanding the feed gas in liquid state, the supply circuit comprising a bypass line of the final expansion turbine fitted with a first expansion valve, a second expansion valve disposed in series upstream or downstream of the first expansion valve and of the final expansion turbine, an additional heat exchange line designed to exchange heat with a heat exchanger of the set of heat exchangers when the feed gas is expanded by the first expansion valve via the bypass line, the additional heat exchange line carrying out this heat exchange with said heat exchanger between the expansion carried out by the first expansion valve and the expansion carried out by the second expansion valve, the additional heat exchange line being located upstream or respectively downstream of the expansion carried out by the first expansion valve.

The present disclosure designs a mixed refrigerant hydrogen liquefaction device including a normal-pressure precooling cold box, a vacuum cryogenic cold box, a hydrogen refrigeration cycle compressor unit, a nitrogen cycle refrigeration unit and a mixed refrigerant cycle refrigeration unit. The precooling section uses a mixed refrigerant process and a nitrogen cycle refrigeration process as the main sources of cold energy. The refrigerant refrigeration cycle is the main source of cold energy in the temperature range of 303K to 113K. The liquid nitrogen refrigeration cycle is the main source of cold energy in the temperature range of 130K to 80K. The hydrogen refrigeration cycle provides cold energy for the temperature range of 80K to 20K. Most of the BOG generated in a storage part is recovered by an ejector. A plate-fin heat exchanger is filled with ortho-para hydrogen conversion catalysts to realize the para hydrogen content of liquefied hydrogen 98%.

A highly efficient refrigeration system and process for precooling of a hydrogen feed stream with concurrent nitrogen liquefaction is disclosed. The disclosed refrigeration system and associated methods employ a reverse Brayton refrigeration cycle using a nitrogen based refrigerant and a fully integrated three pinion bridge (BriM) machine operatively coupling at least two turbine/expanders and at least four nitrogen refrigerant compression stages.

A highly efficient refrigeration system and process for precooling/liquefaction of a hydrogen feed stream and method of turndown of such system is disclosed. The disclosed refrigeration system and associated methods employ a reverse Brayton refrigeration cycle using a nitrogen based refrigerant and a fully integrated three pinion bridge (BriM) machine operatively coupling at least two turbine/expanders and at least four nitrogen refrigerant compression stages. Turndown of the hydrogen precooling and liquefaction process requires removal of nitrogen refrigerant from the refrigeration recycle loop by retaining liquid nitrogen in the phase separator, which is sized to accommodate the bulk of the nitrogen refrigerant used in the refrigeration circuit.

A liquefier system includes: a feed line configured to feed a raw material gas from a raw material supply source such that a pressure of the raw material gas in a predetermined portion of the feed line is kept higher than or equal to a predetermined pressure; a cooling medium circulation line configured to cause a cooling medium to circulate; a static pressure gas bearing configured to be supplied with the gas that has a pressure higher than or equal to the predetermined pressure and to rotatably support a rotating shaft of an expansion turbine; and a bearing supply line configured to connect the predetermined portion of the feed line and a gas inlet of the static pressure gas bearing, such that the gas is supplied to the static pressure gas bearing.

The invention relates to a device (200) for liquefying a gas (51), the device comprising: a circuit (55) for conveying gas to be liquefied, the circuit comprising at least one heat exchanger (204) for exchanging heat between the gas (51) to be liquefied and a refrigerant flow (52) comprising at least dihydrogen refrigerant; a closed refrigeration circuit (210) configured to convey the refrigerant flow,
the closed refrigeration circuit comprising a means (215) for maintaining an internal composition of the dihydrogen refrigerant at a ratio of parahydrogen to orthohydrogen that is lower or higher than the ratio corresponding to a natural equilibrium composition in the refrigerant flow closed circuit, the means (215) comprising a catalytic reactor (220) configured to convert some of the orthohydrogen from the dihydrogen refrigerant flow into parahydrogen or vice versa.

A framed, low-temperature refrigeration device is provided, which includes a working circuit that forms a loop and contains a working fluid, the working circuit forming a cycle that includes in series: a compression mechanism, a cooling mechanism, an expansion mechanism and a heating mechanism, wherein the mechanisms for cooling and heating the working fluid include a common heat exchanger in which the working fluid flows in opposite directions in two separate transit portions of the working circuit. The device may also include a refrigeration heat exchanger for extracting heat from at least one member by exchanging heat with the working fluid flowing in the working circuit, wherein the compression mechanism includes two separate compressors, wherein the mechanism for cooling the working fluid includes two cooling heat exchangers which are arranged respectively at the outlet of the two compressors and ensure heat exchange between the working fluid and a cooling fluid, wherein the frame extends in a longitudinal direction and includes a lower base intended to be mounted on a support, the cooling heat exchangers are located in the frame about the common heat exchanger, i.e. the cooling heat exchangers are not located below the common heat exchanger between the common heat exchanger and the lower base of the frame.

The invention relates to an installation for producing liquefied hydrogen having a gaseous hydrogen generator configured to produce gaseous hydrogen, a liquefier, a supply duct connecting a gaseous hydrogen outlet of the gaseous hydrogen generator to an inlet of the liquefier, the liquefier having a refrigerator having a cycle circuit configured to provide cooling power and cool the gaseous hydrogen from the supply duct with a view to the liquefaction thereof, the installation having at least one compressor for the gaseous hydrogen produced by the gaseous hydrogen generator and a buffer store configured to store the compressed gaseous hydrogen between the gaseous hydrogen generator and the liquefier, the buffer store being connected to the supply duct via a set of bypass duct(s), i.e. the buffer store and the liquefier are connected in parallel to the gaseous hydrogen outlet of the gaseous hydrogen generator.