Abstract: Devices in which a toroidal mass rotates within a pressurized housing vessel, such as rotary wheel Active Magnetic Regenerative Refrigerators (AMRR) and Active Magnetic Regenerative Liquefiers (AMRL), are disclosed. Mechanical gap-type seal designs (e.g., labyrinth seal designs) for controlling (e.g., minimizing) and/or directing fluid flows in the space between a rotating torus and a stationary housing are disclosed. Additional features, such as the use of low friction surface coatings, the generation of low pressure gradients in high pressure heat transfer fluid transiting porous regenerative beds, and the use of pressure bladders to apply adjustable spring pressure to sealing surfaces are also disclosed and contribute to improved device efficiency and desired fluid flows.

Abstract: Apparatus and processes for liquefying process gases using multi-stage active magnetic regenerative refrigerators are disclosed. The apparatus and processes can be configured to liquefy process streams that liquefy below ˜200 K, such as ethane, methane, argon, nitrogen, neon, hydrogen and/or helium process gases. Active magnetic regenerative liquefiers use multiple successive active magnetic regenerator stages, with each stage using a compositionally distinct magnetic refrigerant material having a distinct Curie temperature. In some aspects, the refrigerant material in each successive stage has a Curie temperature of about 20 K-40K different from that of neighboring stages. Heat transfer fluid flows are directed to improve system efficiency.