Patent US3947259A successfully refreshed from Google Patents.
US3947259A
Expired / Lapsed
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Thermodynamically improved system for producing gaseous oxygen and gaseous nitrogen
Assignee: Linde GmbH
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Filing: 1974-07-10
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Granted: 1976-03-30
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Expires: 1994-07-10
Abstract
Abstract A process for producing gaseous oxygen and gaseous nitrogen by the low-temperature rectification of air in a double rectification column having a low-pressure section and a high-pressure section, comprising warming a process stream in a cold section of a reversible heat exchange zone against entering air and thereupon engine-expanding resultant warmed process stream, the improvement wherein a portion is branched off from the warmed process stream prior to its expansion, which portion is liquefield in a condenser-evaporator of the double rectifying column, is subcooled, and is then expanded into the low-pressure section (7) of the double rectifying column (8).
Inventors
- 👤 Klaus Frischbier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:09
CPC Classifications
F; F25; F25J; F25J3/00; F25J3/02; F25J3/04; F25J3/04151; F25J3/04187; F25J3/04193; F25J3/04248; F25J3/04284; F25J3/04309; F25J3/04406; F25J3/04412; F25J2205/00; F25J2205/24; F25J2245/00; F25J2245/42; F25J2250/00; F25J2250/20
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
143 words
In a process for producing gaseous oxygen and gaseous nitrogen by the low-temperature rectification of air in a double rectification column having a low-pressure section and a high-pressure section, comprising warming a cold gaseous process stream having a temperature in the range of liquid air in a reversible heat exchanger zone with entering gaseous air to compensate for cold values required for the condensation and removal of CO 2 and H 2 O from the air, and thereupon engine-expanding resultant warmed process stream, the improvement comprising branching a portion from the resultant warmed process stream prior to engine expansion of said resultant warmed process stream, liquefying said portion substantially completely in a condenser-evaporator unit of the double rectifying column, subcooling resultant liquefied portion to below its liquefaction temperature, and expanding resultant subcooled liquefied portion into the low-pressure section of the double rectification column.
Claim 2
Dependent Claim
143 words
In a process for producing gaseous oxygen and gaseous nitrogen by the low-temperature rectification of air in a double rectification column having a low-pressure section and a high-pressure section, comprising warming a cold gaseous process stream having a temperature in the range of liquid air in a reversible heat exchanger zone with entering gaseous air to compensate for cold values required for the condensation and removal of CO 2 and H 2 O from the air, and thereupon engine-expanding resultant warmed process stream, the improvement comprising branching a portion from the resultant warmed process stream prior to engine expansion of said resultant warmed process stream, liquefying said portion substantially completely in a condenser-evaporator unit of the double rectifying column, subcooling resultant liquefied portion to below its liquefaction temperature, and expanding resultant subcooled liquefied portion into the low-pressure section of the double rectification column.
Claim 3
Dependent Claim
24 words
A process according to claim 1, wherein gaseous nitrogen from the high-pressure section of the double rectifying column is utilized as the process stream.
Claim 4
Dependent Claim
52 words
A process according to claim 2, wherein the engine-expanded portion of the process stream and the portion of the process stream to be liquefied are cooled with nitrogen from the low-pressure section of the double rectifying column and resultant cooled engine-expanded portion of the process stream is warmed against entering raw air.
Claim 5
Dependent Claim
24 words
A process according to claim 1, wherein said cold process steam is an air fraction from the high-pressure section of the double rectifying column.
Claim 6
Dependent Claim
23 words
A process according to claim 1, wherein said cold process stream is a portion of the air cooled to the dew point temperature.
Claim 7
Dependent Claim
26 words
A process according to claim 4, wherein the engine-expanded portion of the process stream is introduced directly into the low-pressure section of the double rectifying column.
Claim 8
Dependent Claim
26 words
A process according to claim 5, wherein the engine-expanded portion of the process stream is introduced directly into the low-pressure section of the double rectifying column.
Claim 9
Dependent Claim
34 words
A process according to claim 1 wherein the branched-off portion is not recombined with the remainder of the resultant warmed process stream and engine-expanded together with the remainder of the resultant warmed process stream.
Claim 10
Dependent Claim
22 words
A process according to claim 1 wherein the liquefied branched-off portion has the same composition as the branched-off portion prior to liquefaction.
Claim 11
Dependent Claim
22 words
A process according to claim 8 wherein the liquefied branche-off portion has the same composition as the branched-off portion prior to liquefaction.
Claim 12
Dependent Claim
32 words
A process according to claim 1 wherein said branched-off portion is passed into said condenser-evaporator at substantially the same pressure as the pressure of the warmed process stream prior to its expansion.
Claim 13
Dependent Claim
22 words
A process according to claim 10 wherein the liquefied branched-off portion has the same composition as the branched-off portion prior to liquefaction.
Claim 14
Dependent Claim
22 words
A process according to claim 11 wherein the liquefied branched-off protion has the same composition as the branched-off portion prior to liquefaction.
Claim 15
Dependent Claim
41 words
A process according to claim 13 wherein said cold process stream which is warmed in the reversible heat exchange zone amounts to about 11-13% of the total air throughput, and the branched-off portion amounts to 3-6% of the total air throughput.
Claim 16
Dependent Claim
19 words
A process according to claim 14 wherein said branched-off portion amounts to about 5-6% of the total air throughput.
Claim 17
Dependent Claim
41 words
A process according to claim 1 wherein said cold process stream which is warmed in the reversible heat exchange zone amounts to about 11-13% of the total air throughput, and the branched-off portion amounts to 3-6% of the total air throughput.
Claim 18
Dependent Claim
19 words
A process according to claim 1 wherein said branched-off portion amounts to about 5-6% of the total air throughput.
References Cited (Backward Citations)
US3066494A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-03-30 | 1979-09-29 | 1980-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-30 | 1983-09-29 | 1984-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-03-30 | 1987-09-29 | 1988-03-30 | $7700.00 | Window Closed / Lapsed |