US4152130A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of liquid oxygen and/or liquid nitrogen
Assignee: Air Products and Chemicals Inc
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Filing: 1978-03-16
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Granted: 1979-05-01
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Expires: 1998-03-16
Abstract
Abstract Liquid oxygen and/or liquid nitrogen are made by removing carbon dioxide and water vapor from air, compressing the purified air in a re-cycle compressor and dividing the purified compressed air into first and second streams. Part of the first stream is expanded in a first expander and the refrigeration produced is used to cool both the first and second streams in a first heat exchanger. On leaving the first heat exchanger, the second stream is expanded in a second expander and the refrigeration produced is used to liquify at least part of the remainder of the first stream. The liquid stream is expanded and introduced into a fractionation column from which liquid nitrogen and/or liquid oxygen can be withdrawn. Expanded air from the first and second expanders is returned to the re-cycle compressor although part of the expanded air from the second expander is preferably introduced into the fractionation column. The invention is particularly suited to installations producing in excess of 100 tons of liquid per day and, at this size, preferred designs offer an estimated 51/2 to 9% power savings over the known prior art.
Inventors
- 👤 Alan Theobald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:51
CPC Classifications
F; F25; F25J; F25J3/00; F25J3/02; F25J3/04; F25J3/04406; F25J3/04412; F25J3/04151; F25J3/04157; F25J3/04163; F25J3/04169; F25J3/04181; F25J3/04248; F25J3/04284; F25J3/0429; F25J3/04296; F25J3/04333; F25J3/04339; F25J3/04345; F25J3/04375; F25J3/04393; F25J3/04763; F25J3/04769; F25J3/04854; F25J3/0486; F25J2205/00; F25J2205/02; F25J2205/04; F25J2205/60; F25J2205/66; F25J2205/68; F25J2205/70; F25J2210/00; F25J2210/06; F25J2215/00; F25J2215/42; F25J2215/44; F25J2245/00; F25J2245/50; F25J2270/00; F25J2270/90; Y; Y10; Y10S; Y10S62/00; Y10S62/939; Y10S62/94
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
293 words
A method for producing at least one liquid product from the group of liquid oxygen and liquid nitrogen comprising the steps of: (a) drying and removing carbon dioxide from a feed air stream to form a dry, carbon dioxide-free feed air stream; (b) compressing said dry, carbon dioxide-free feed air stream in at least one recycle compressor to a pressure above 425 psia; (c) dividing said compressed feed air stream into first and second feed air streams; (d) dividing said first feed air stream into a sidestream and a remaining stream; (e) expanding said sidestream to a lower pressure and temperature, and cooling said remaining stream and said second stream in heat exchange relationship with said expanded sidestream; (f) expanding said second stream, after cooling in clause (e), to a lower pressure and temperature, and further cooling said once cooled remaining stream in heat exchange relationship with a first portion of said expanded second stream; (g) expanding said twice cooled remaining feed air stream to a lower pressure, and injecting said expanded and cooled remaining feed air stream at least partially as a liquid, into a distillation column as a first feed air stream to the column; (h) injecting a second portion of said expanded second stream into said distillation column as a second air feed stream to said column; (i) recycling the exapnded streams of steps (e) and (f) to said recycle compressor as recycled feed air streams along with said initially dry carbon dioxide-free feed air stream; (j) separating said first and second feed air streams in said distillation column and producing both liquid oxygen and liquid nitrogen in said column; and (k) withdrawing at least one of said liquid oxygen and liquid nitrogen from said distillation column as liquefied product.
Claim 2
Independent Claim
293 words
A method for producing at least one liquid product from the group of liquid oxygen and liquid nitrogen comprising the steps of: (a) drying and removing carbon dioxide from a feed air stream to form a dry, carbon dioxide-free feed air stream; (b) compressing said dry, carbon dioxide-free feed air stream in at least one recycle compressor to a pressure above 425 psia; (c) dividing said compressed feed air stream into first and second feed air streams; (d) dividing said first feed air stream into a sidestream and a remaining stream; (e) expanding said sidestream to a lower pressure and temperature, and cooling said remaining stream and said second stream in heat exchange relationship with said expanded sidestream; (f) expanding said second stream, after cooling in clause (e), to a lower pressure and temperature, and further cooling said once cooled remaining stream in heat exchange relationship with a first portion of said expanded second stream; (g) expanding said twice cooled remaining feed air stream to a lower pressure, and injecting said expanded and cooled remaining feed air stream at least partially as a liquid, into a distillation column as a first feed air stream to the column; (h) injecting a second portion of said expanded second stream into said distillation column as a second air feed stream to said column; (i) recycling the exapnded streams of steps (e) and (f) to said recycle compressor as recycled feed air streams along with said initially dry carbon dioxide-free feed air stream; (j) separating said first and second feed air streams in said distillation column and producing both liquid oxygen and liquid nitrogen in said column; and (k) withdrawing at least one of said liquid oxygen and liquid nitrogen from said distillation column as liquefied product.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-04-30 | 1982-10-30 | 1983-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-04-30 | 1986-10-30 | 1987-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-04-30 | 1990-10-30 | 1991-05-01 | $7700.00 | Window Closed / Lapsed |