A system and a method for recovery and recycling of gases which are utilized in their liquid state as refrigerants in applications that require low temperatures, throughout various pressure ranges, from slightly above atmospheric pressures to pressures near the critical point for the particular gas. The system and method are based on closed-cycle cryocoolers and utilize the thermodynamic properties of the gas to achieve optimal liquefaction rates.

The method for producing liquid hydrogen can include the steps of: introducing pressurized natural gas from a high pressure natural gas pipeline to a gas processing unit under conditions effective for producing a purified hydrogen stream; and introducing the purified hydrogen stream to a hydrogen liquefaction unit under conditions effective to produce a liquid hydrogen stream, wherein the hydrogen liquefaction unit provides a warm temperature cooling and a cold temperature cooling to the purified hydrogen stream, wherein the warm temperature cooling is provided by utilizing letdown energy of a pressurized stream selected from the group consisting of a nitrogen stream sourced from a nitrogen pipeline, a natural gas stream sourced from the high pressure natural gas pipeline, an air gas sourced from an air separation unit, and combinations thereof, wherein the cold temperature is provided by utilizing letdown energy of the purified hydrogen stream.

Disclosed is a small-scale hydrogen liquefaction system using cryocoolers. The system includes: a gas supply line to supply a gaseous hydrogen; n cryocoolers each connected to the gas supply line to be connected in parallel and configured such that the gaseous hydrogen supplied from the gas supply line is divided into n portions, and the n portions flow through the n cryocoolers, respectively, and are cooled to a liquefaction temperature, wherein n is a natural number equal to or greater than 2; n heat exchangers each attached to a cold head of each of the n cryocoolers; and a low-temperature chamber providing an accommodation space to accommodate the n cryocoolers therein.

A process for liquefying a process gas comprising: introducing a heat transfer fluid into an active magnetic regenerative refrigerator apparatus that comprises (i) a high magnetic field section in which the heat transfer fluid flows from a cold side to a hot side through at least one magnetized bed of at least one magnetic refrigerant, (ii) a first no heat transfer fluid flow section in which the bed is demagnetized, (iii) a low magnetic or demagnetized field section in which the heat transfer fluid flows from a hot side to a cold side through the demagnetized bed, and (iv) a second no heat transfer fluid flow section in which the bed is magnetized; continuously diverting a bypass portion of the heat transfer fluid from the cold side of the low magnetic or demagnetized field section into a bypass flow heat exchanger at a first cold inlet temperature; and continuously introducing the process gas into the bypass flow heat exchanger at a first hot inlet temperature and discharging the process gas or liquid from the bypass flow heat exchanger at a first cold exit temperature; wherein the temperature difference between bypass heat transfer first cold inlet temperature and the process gas first cold exit temperature is 1 to 5 K.

An active gas regenerative refrigerator includes a plurality of compressor-expander units, each having a hermetic cylinder with a drive piston configured to be driven reciprocally therein, and a quantity of working fluid in each end of the cylinder. A piston seal in a central portion of the cylinder prevents passage of the working fluid between ends of the cylinder. Movement of the piston to a first extreme results in radial compression of one of the quantities of working fluid in a cylindrical gap formed between one end of the piston and an inner surface of the cylinder, while the other quantity is expanded in the opposite end of the cylinder. The piston includes a plurality of magnets arranged in pairs, with magnets of each pair positioned with like-poles facing each other. A piston drive is configured to couple with transverse magnetic flux regions formed by the magnets.

Liquefaction of industrial gases or gas mixtures (hydrocarbon and/or non-hydrocarbon) uses a modified aqua-ammonia absorption refrigeration system (ARP) to chill the gas or gas mixture during the liquefaction process. The gas is compressed to above its critical point, and the heat of compression energy may be recovered to provide some or all of the thermal energy required to drive the ARP. A Joule Thomson (JT) adiabatic expansion process results in no requirement for specialty cryogenic rotating equipment. The aqua-ammonia absorption refrigeration system includes a vapour absorber tower (VAT) that permits the recovery of some or all of the heat of solution and heat of condensation energy in the system when anhydrous ammonia vapour is absorbed into a subcooled lean aqua-ammonia solution. The modified ARP with VAT may operate at pressures as low as 10 kPa, and the ammonia gas chiller may operate at temperatures as low as 71 C.

Disclosed are a helium gas liquefier and a method for liquefying a helium gas. The disclosed helium gas liquefier includes: a first cooling part including a first cooling column; a first cold head installed on the first cooling column, and a first cylinder in which the first cooling column and the first cold head are built; a second cooling part including a second cooling column, a second cold head installed on the second cooling column, and a second cylinder in which the second cooling column and the second cold head are built; and a liquid helium storage disposed under the second cooling part.

A process for liquefying a process gas that includes: introducing a heat transfer fluid into an active magnetic regenerative refrigerator apparatus that includes a low magnetic or demagnetized field section; continuously diverting a bypass portion of the heat transfer fluid from a cold side of the low magnetic or demagnetized field section into a bypass flow heat exchanger at a first cold inlet temperature; and continuously introducing the process gas into the bypass flow heat exchanger at a first hot inlet temperature and discharging the process gas or liquid from the bypass flow heat exchanger at a first cold exit temperature; wherein the temperature difference between bypass heat transfer first cold inlet temperature and the process gas first cold exit temperature is 1 to 5 K.

A method for liquefaction of industrial gases or gas mixtures (hydrocarbon and/or non-hydrocarbon) uses a modified aqua-ammonia absorption refrigeration system (ARP) that is used to chill the gas or gas mixture during the liquefaction process. The gas may be compressed to above its critical point, and the heat of compression energy may be recovered to provide some or all of the thermal energy required to drive the ARP. The method utilizes a Joule Thomson (JT) adiabatic expansion process which results in no requirement for specialty cryogenic rotating equipment. The aqua-ammonia absorption refrigeration system includes a vapor absorber tower (VAT) which permits the recovery of some or all of the heat of solution and heat of condensation energy in the system when anhydrous ammonia vapor is absorbed into a subcooled lean aqua-ammonia solution. The modified ARP with VAT may achieve operating pressures as low as 10 kPa which results in ammonia gas chiller operating temperatures as low as 71 C.

A system for renewable energy storage, providing integral synthesis of heat source cryo-fuel and heat sink refrigerant for distributed electric generation and motor vehicle prime movers and refrigerant liquefiers. Fuel synthesis is by gasification and anaerobic digestion of organic feedstock with heat recovery to drive thermo-chemical reactor and air and fuel liquefiers.