Apparatus and methods for cooling and liquefying a fluid using magnetic refrigeration

• US 20020040583A1
• Filed: 05/07/2001
• Published: 04/11/2002
• Est. Priority Date: 05/05/2000
• Status: Active Grant

• Current Assignee: Prometheus Technologies LCC
• Original Assignee: University of Victoria Innovation and Development Corporation
• Inventors: Barclay, John A., Brook, Thomas C.
• Granted Patent: US 6,467,274 B2
• Time in Patent Office: Days
• US Class Current: 62/3.1
• CPC Class Codes: F25B 21/00 Machines, plants or systems, using electric or magnetic effects
• CPC Class Codes: F25B 2321/0021 with a static fixed magnet
• CPC Class Codes: F25J 1/001 Hydrogen
• CPC Class Codes: F25J 1/0022 Hydrocarbons, e.g. natural gas
• CPC Class Codes: F25J 1/0225 using other external refrigeration means not provided before, e.g. heat driven absorption chillers
• CPC Class Codes: F25J 2270/908 by regenerative chillers, i.e. oscillating or dynamic systems, e.g. Stirling refrigerator, thermoelectric ("Peltier") or magnetic refrigeration
• CPC Class Codes: Y02B 30/00 Energy efficient heating, ventilation or air conditioning [HVAC]

Abstract

Methods and apparatus for magnetically cooling and liquefying a process stream include a plurality of active magnetic regenerative refrigerators (AMRRs) configured in parallel or in series and parallel. Active magnetic regenerative liquefiers (AMRLs) include such AMRRs and are configured to liquefy, for example, natural gas or hydrogen. In specific embodiments, a magnetic field is produced by hexagonally arrayed solenoids and magnetic refrigerants are selected to provide a thermal mass that is dependent on an applied magnetic field.

Claims

1. An active magnetic regenerative liquefier (AMRL), comprising:

at least a first and a second active magnetic refrigerators (AMRRs), the first AMRR configured to receive and cool a process stream, and deliver the process stream to the second AMRR, wherein the first and second AMRRs have respective thermal reservoirs at a common temperature.

2. The AMRL of claim 1, further comprising at least a fourth through a sixth AMRL, the fourth through sixth AMRLs configured to serially receive and cool a process stream.

3. The AMRL of claim 2, wherein the first through sixth AMRLs have respective cold reservoirs at temperatures of about 192, 120, 78, 48, 32, and 20 K, respectively.

4. The AMRL of claim 3, wherein the first through third AMRLs are arranged in parallel.

5. The AMRL of claim 4, wherein the fourth through sixth AMRLs are arranged in series.

6. The AMRL of claim 2, wherein the first through third AMRLs are arranged in parallel.

7. The AMRL of claim 4, wherein the fourth through sixth AMRLs are arranged in series.

8. A hydrogen liquefier, comprising an AMRL as recited in claim 2.

9. A hydrogen liquefier, comprising:

at least three active magnetic regenerator refrigerators (AMRRs) situated and configured to receive and serially cool a hydrogen process stream; and

at least two ortho to para convertors situated between at least two of the AMRRs.

10. An active magnetic regenerator refrigerator (AMRR), comprising:

a magnet that includes at least two solenoids that are situated and configured to produce a magnetic field along oppositely directed axes;

a magnetic refrigerating matrix arranged to be movable into and out of a magnetic field produced by the magnet and configured to cool a process stream.

11. The AMRR of claim 10, wherein the magnet includes six solenoids that are hexagonally arranged and that produce magnetic fields that are alternately directed along opposite directions.

12. The AMRR of claim 10, further comprising a hot-blow zone duct situated and configured to direct a heat-transfer fluid through and past the magnetic refrigerating matrix passing within a region of magnetic field produced by the magnet.

13. The AMRR of claim 12, further comprising a seal that substantially confines the heat-transfer fluid so that the heat-transfer fluid passes through the magnetic refrigerating matrix.

14. The AMRR of claim 12, further comprising a cold-blow-zone duct situated and configured to direct the heat-transfer fluid through and past the magnetic refrigerating matrix in a region substantially without magnetic field produced by the magnet.

15. The AMRR of claim 10, further comprising a belt, wherein the magnetic refrigerating matrix is attached to the belt.

16. The AMRR of claim 10, further comprising a belt, wherein the magnetic refrigerating matrix includes segments arranged in at least one row on the belt.

17. The system of claim 16, where the belt is rotatable at a rate of at least 1 revolution/second.

18. The system of claim 16, where the belt is rotatable at a rate of at least 3 revolutions/second.

19. The AMRR of claim 10, wherein the heat-transfer fluid is helium gas.

20. The AMRR of claim 10, further comprising a flexible chain, wherein the magnetic refrigerating matrix is attached to the flexible chain.

21. The AMRR of claim 20, wherein the flexible chain is rotatable at a rate of at least 1 revolution/second.

22. The AMRR of claim 20, where the flexible chain is rotatable at a rate of at least 3 revolutions/second.

24. The liquefier of claim 23, wherein the solenoids are configured to produce respective magnetic fields having alternately opposing orientations with respect to an axis, thereby increasing magnetic flux density.

25. The liquefier of claim 24 configured to liquefy natural gas.

26. The liquefier of claim 24 configured to liquefy hydrogen gas.

28. The magnetic regenerator segment of claim 27, wherein the magnetic refrigerants are selected so that a thermal mass of the magnetic regenerator segment is lower in a magnetic field.

23. A liquefier, comprising an at least six magnetic cooling stages, wherein the cooling stages are situated and configured to receive a magnetic field from a hexagonal array of solenoids that includes a frame that is configured to conduct respective magnetic fluxes produced by the solenoids.

27. A magnetic regenerator segment, comprising at least two magnet refrigerants selected based on a predetermined average operating temperature for each of the magnetic refrigerants.