A refrigerant management system controls the supply of refrigerant from two or more variable speed and fixed speed compressors to a plurality of cryogenic refrigerators. The system employs a plurality of sensors to monitor and regulate the overall refrigerant supply to deliver an appropriate refrigerant supply to each of the cryogenic refrigerators. The amount of refrigerant to supply is based on an aggregate demand for refrigerant from the plurality of cryogenic refrigerators and a refrigerant correction metric. An appropriate supply of refrigerant is distributed to each cryogenic refrigerator by adjusting the speed of the variable speed compressors or, alternatively, selectively turning the compressors on or off. The speed of the variable speed compressors is adjusted by determining an amount of refrigerant to supply to the plurality of cryogenic refrigerators. If the aggregate demand for refrigerant exceeds the capacity of the compressors, then the speed of a refrigerator within the plurality of refrigerators is adjusted.

Provided is a production facility for liquefied hydrogen and a liquefied natural gas from a natural gas, including: a first heat exchanger configured to cool a hydrogen gas through heat exchange between the hydrogen gas and a mixed refrigerant for liquefying a natural gas containing a plurality of kinds of refrigerants selected from the group consisting of methane, ethane, propane, and nitrogen; a second heat exchanger configured to cool the mixed refrigerant through heat exchange between the mixed refrigerant and propane; and a third heat exchanger configured to cool the hydrogen gas through heat exchange between the hydrogen gas and a refrigerant containing hydrogen or helium, wherein the first heat exchanger has a precooling temperature of from 100 C. to 160 C.

A system and method for the production and supply of a densified, liquid oxidant to a space vehicle launch facility with one or more launch platforms is provided. In one embodiment, a low pressure gaseous oxygen stream is piped from a nearby air separation unit to the space vehicle launch facility where it is then liquefied and densified in a two-stage, integrated liquefaction/densification system. In an alternate embodiment, a liquid oxygen stream produced at an air separation unit is densified in a two-stage, integrated densification system at or near the air separation unit with the resulting densified liquid oxygen product transported via truck/trailer to a nearby space vehicle launch facility.

The present invention relates to a cryocooler suitable for gas liquefaction applications, that comprises a coldhead with one or more refrigeration stages; further comprising: a refrigerator compressor for distributing compressed gas-phase cryogen inside the coldhead; a heat exchanging coil arranged at least partially around the external region of the coldhead; at least one extraction orifice communicating a gas circulation circuit inside the coldhead with the heat exchanging coil; acting said extraction orifice/s as pass-through port/s which allow the gas inside the coldhead to flow through the inside of the heat exchanger coil for exchanging heat with the exterior thereof, and wherein the heat exchanging coil is adapted to connect and redirect the gas to one return port connected to the gas circulation circuit. Another object of the invention relates to a cryogen-gas liquefaction system and a method for liquefaction of gases that comprises said system.

The present invention discloses a hydrogen or helium throttling liquefaction system using direct current (DC) flow from the cold and hot ends of the regenerative cryocoolers, which belongs to the technical field of refrigeration and cryogenics. It includes a regenerative cryocooler module, a hot-end DC flow module, a cold-end DC flow module, a throttling liquefaction module, and a gas-phase circulation module. The modules are interconnected to form a closed loop for the flow of hydrogen or helium working fluid. DC flow is introduced from the cold and hot ends of the regenerative cryocooler through the DC flow pipelines and DC flow valves. The hot-end DC flow exchanges heat with the reflowing low-temperature working fluid and is cooled down. After that, it mixes with the cold-end DC flow and enters the throttling liquefaction module to generate liquid phase through throttling and liquefaction. After the liquid phase has output cooling capacity, it flows through the gas-phase circulation module and then enters the back-pressure chamber of the compressor to complete the cycle. Compared with the existing small-scale hydrogen and helium liquefaction technology using regenerative cryocoolers, the present invention has the advantages of simple structure, easy installation, high heat transfer efficiency and liquefaction efficiency of the system.

The present invention relates to a method for liquefying hydrogen, the method comprises the steps of: cooling a feed gas stream comprising hydrogen with a pressure of at least 15 bar(a) to a temperature below the critical temperature of hydrogen in a first cooling step yielding a liquid product stream. According to the invention, the feed gas stream is cooled by a closed first cooling cycle with a high pressure first refrigerant stream comprising hydrogen, wherein the high pressure first refrigerant stream is separated into at least two partial streams, a first partial stream is expanded to low pressure, thereby producing cold to cool the precooled feed gas below the critical pressure of hydrogen, and compressed to a medium pressure, and wherein a second partial stream is expanded at least close to the medium pressure and guided into the medium pressure first partial stream.

The present invention relates to a refrigerant composition. According to the invention it is envisioned that the composition comprises comprising an inert gas selected from nitrogen, argon, neon and a mixture thereof, and a mixture of at least two C.sub.1-C.sub.5 hydrocarbons. The present invention further relates to the use of the refrigerant composition in a method for liquefying a gaseous substance, particularly hydrogen or helium.

The present invention relates to a refrigerant composition comprising neon and hydrogen. The present invention further relates to the use of the refrigerant composition in liquefying gaseous substances such as hydrogen or helium.

A refrigerant management system controls the supply of refrigerant from two or more variable speed and fixed speed compressors to a plurality of cryogenic refrigerators. The system employs a plurality of sensors to monitor and regulate the overall refrigerant supply to deliver an appropriate refrigerant supply to each of the cryogenic refrigerators. The amount of refrigerant to supply is based on an aggregate demand for refrigerant from the plurality of cryogenic refrigerators and a refrigerant correction metric. An appropriate supply of refrigerant is distributed to each cryogenic refrigerator by adjusting the speed of the variable speed compressors or, alternatively, selectively turning the compressors on or off. The speed of the variable speed compressors is adjusted by determining an amount of refrigerant to supply to the plurality of cryogenic refrigerators. If the aggregate demand for refrigerant exceeds the capacity of the compressors, then the speed of a refrigerator within the plurality of refrigerators is adjusted.

The present disclosure relates to a hydrogen liquefaction system, comprising a hydrogen pipe, where gaseous hydrogen is introduced at a front end, heat exchange occurs in a heat exchange unit leading to liquefaction of gaseous hydrogen into liquid hydrogen; a pre-cooling device formed between the front end of the hydrogen pipe and the first heat exchange unit; an oxygen pipe, where gaseous oxygen is introduced at a front end, heat exchange occurs in the pre-cooling device leading to liquefaction of gaseous oxygen into liquid oxygen; and a heat exchange device, which is in thermal contact with the first heat exchange unit of the hydrogen pipe so as to perform heat exchange with the first heat exchange unit of the hydrogen pipe such that pre-cooled gaseous hydrogen can be liquefied into liquid hydrogen.