US 12,298,075 B2
Process and apparatus for recovery of at least nitrogen and argon
Donn Michael Herron, Fogelsville, PA (US); and Qiao Zhao, Macungie, PA (US)
Assigned to AIR PRODUCTS AND CHEMICALS, INC., Allentown, PA (US)
Filed by Air Products and Chemicals, Inc., Allentown, PA (US)
Filed on Aug. 1, 2022, as Appl. No. 17/878,171.
Prior Publication US 2024/0035743 A1, Feb. 1, 2024
Int. Cl. F25J 3/04 (2006.01)
CPC F25J 3/04412 (2013.01) [F25J 3/04018 (2013.01); F25J 3/04187 (2013.01); F25J 3/04351 (2013.01); F25J 3/04363 (2013.01); F25J 3/04666 (2013.01); F25J 2200/06 (2013.01); F25J 2200/34 (2013.01); F25J 2210/06 (2013.01); F25J 2210/40 (2013.01); F25J 2215/42 (2013.01); F25J 2215/58 (2013.01); F25J 2270/42 (2013.01); F25J 2270/50 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A process for separation of a feed gas comprising oxygen, nitrogen, and argon, the process comprising:
compressing a feed gas via a compression system of a separation system having at least a first column and a second column, the first column being a high pressure (HP) column operating at a pressure that is higher than the second column, the second column being a low pressure (LP) column operating at a pressure that is lower than the first column;
feeding a first feed stream portion of the compressed feed gas to a first heat exchanger to cool the first feed stream portion of the compressed feed gas;
feeding the cooled first feed stream portion of the compressed feed gas to the HP column to produce an HP nitrogen-rich vapor stream and an HP oxygen-enriched stream;
condensing a first portion of the HP nitrogen-rich vapor stream via an HP reboiler-condenser to form an HP condensate stream so that a first portion of the HP condensate stream is recyclable to the HP column;
outputting at least LP nitrogen-enriched stream, a first LP oxygen-enriched stream, and an LP argon-enriched stream from the LP column, the first LP oxygen-enriched stream having an oxygen content of at least 97 mol % oxygen;
feeding the LP argon-enriched stream to a third column to form an argon-rich vapor and an argon-depleted liquid, the third column being an argon-enrichment (AE) column;
feeding the formed argon-rich vapor to an AE column reboiler-condenser;
feeding the argon-depleted liquid to the LP column;
at least partially condensing the argon-rich vapor output from the AE column via the AE column reboiler-condenser;
mixing the LP nitrogen-enriched stream output from the LP column with the first LP oxygen-enriched stream output from the LP column to form a first mixed nitrogen-oxygen fluid to feed to the AE column reboiler-condenser where it is at least partially vaporized to provide at least a portion of a refrigeration duty of the AE column reboiler-condenser for at least partially condensing the first argon-rich vapor; and
feeding a first portion of the at least partially vaporized first mixed nitrogen-oxygen fluid to the LP column.