US5019145A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Argon purification
Assignee: Linde GmbH
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Filing: 1989-11-30
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Granted: 1991-05-28
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Expires: 2009-11-30
Abstract
Abstract A process and apparatus for air separation by low temperature rectification are described in which argon is obtained exclusively by rectification. A crude argon column (24) is equipped with at least 150 theoretical plates in the form of low pressure drop packing so that, in it, a substantially complete separation of the oxygen is possible, e.g., less than about 10 ppm, preferably less than 1 ppm oxygen.
Inventors
- 👤 Wilhelm Rohde
- 👤 Horst Corduan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 18:03
CPC Classifications
F; F25; F25J; F25J3/00; F25J3/02; F25J3/04; F25J3/04248; F25J3/04284; F25J3/0429; F25J3/04303; F25J3/04406; F25J3/04412; F25J3/04642; F25J3/04648; F25J3/04654; F25J3/04666; F25J3/04672; F25J3/04678; F25J3/04721; F25J3/04727; F25J2200/00; F25J2200/90; F25J2235/00; F25J2235/58; F25J2250/00; F25J2250/30; F25J2250/42; F25J2250/58; F25J2290/00; F25J2290/12; Y; Y10; Y10S; Y10S62/00; Y10S62/923; Y10S62/924; Y10S62/939
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
163 words
In a process for air separation by low temperature rectification of air, in which air is compressed, prepurified, cooled, fed to a double rectification column comprising a high pressure column having a top and a bottom, said top being in heat exchange relationship with a low pressure column, and separated into an oxygen-rich and a nitrogen-rich fraction, and from the low pressure column of the rectification, an oxygen fraction enriched with argon is removed and, in a crude argon rectification, is separated into crude argon and a higher boiling residual fraction, the improvement which comprises conducting the crude argon rectification in a column having a head condenser, at least 150 theoretical plates, and provided with low pressure drop structured packings or fillings; and cooling the head condenser with liquid from the bottom of the high pressure column, said crude argon rectification resulting in a sufficient separation of oxygen to eliminate any use of a deoxo unit to remove oxygen from the resultant argon.
Claim 2
Dependent Claim
163 words
In a process for air separation by low temperature rectification of air, in which air is compressed, prepurified, cooled, fed to a double rectification column comprising a high pressure column having a top and a bottom, said top being in heat exchange relationship with a low pressure column, and separated into an oxygen-rich and a nitrogen-rich fraction, and from the low pressure column of the rectification, an oxygen fraction enriched with argon is removed and, in a crude argon rectification, is separated into crude argon and a higher boiling residual fraction, the improvement which comprises conducting the crude argon rectification in a column having a head condenser, at least 150 theoretical plates, and provided with low pressure drop structured packings or fillings; and cooling the head condenser with liquid from the bottom of the high pressure column, said crude argon rectification resulting in a sufficient separation of oxygen to eliminate any use of a deoxo unit to remove oxygen from the resultant argon.
Claim 3
Dependent Claim
17 words
A process according to claim 1, the resultant crude argon containing at most about 10 ppm oxygen.
Claim 4
Dependent Claim
17 words
A process according to claim 1, the resultant crude argon containing at most about 1 ppm oxygen.
Claim 5
Dependent Claim
17 words
A process according to claim 1, wherein the crude argon rectification column has about 180 theoretical plates.
Claim 6
Dependent Claim
35 words
A process according to claim 1, further comprising separating the crude argon from the crude argon rectification in a pure argon rectification so as to yield a pure argon and a lower boiling residual fraction.
Claim 7
Dependent Claim
82 words
Apparatus for performing the process according to claim 1 comprising a double rectification column comprising a high pressure column having a top and bottom and a low pressure column superimposed on said high pressure column, a crude argon column having a head condenser and provided with sufficient structured packings or filled material so as to amount to at least 150 theoretical plates, and a conduit connecting the bottom of the high pressure column with the head condenser of the crude argon column.
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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) | 1994-05-27 | 1994-11-26 | 1995-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-05-27 | 1998-11-26 | 1999-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-05-27 | 2002-11-26 | 2003-05-28 | $7700.00 | Window Closed / Lapsed |