US3751934A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Concentrating krypton and xenon in air separation by liquid oxygen wash
Assignee: Individual
•
Filing: 1971-11-08
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Granted: 1973-08-14
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Expires: 1991-11-08
Abstract
Abstract In air separation, oxygen containing krypton, xenon and hydrocarbons is passed from the rectifying column to a separator where as a rising gas it is washed with a controlled downflow of liquid oxygen drawn from above the sump liquid in the column. The controlled washing permits gaseous oxygen and some methane to leave the separator top while krypton and xenon are trapped in the wash liquid which returns from the separator bottom to the column sump. Thus enriched sump liquid is withdrawn for further processing to recover krypton and xenon.
Inventors
- 👤 K Frischbier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 09:21
CPC Classifications
F; F25; F25J; F25J3/00; F25J3/02; F25J3/04; F25J3/04406; F25J3/04412; F25J3/04642; F25J3/04745; F25J3/04763; F25J3/04866; F25J3/04872; F25J3/04884; F25J2200/00; F25J2200/34; F25J2205/00; F25J2205/30; F25J2235/00; F25J2235/50; F25J2245/00; F25J2245/50; F25J2250/00; F25J2250/02; Y; Y10; Y10S; Y10S62/00; Y10S62/923; Y10S62/925
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
88 words
The process of claim 1 wherein the stream of oxygen containing increased quantities of krypton, xenon and hdyrocarbons from below the bottom tray in the air rectifying column is liquid from the sump of said air rectifying column, said liquid is partially vaporized before being passed to below the bottom tray in the concentrating rectifying column, and part of the vapor of the partially vaporized liquid is passed from below the bottom tray in said concentrating rectifYIng column to below the bottom tray in said air rectifying column.
Claim 2
Dependent Claim
34 words
The process of claim 1 wherein the adjustment of the discharge of liquid oxygen into the top of the concentrating rectifying colomn provides a liquid-to-vapor ratio in the range of about 0.05 to 0.02.
Claim 3
Dependent Claim
45 words
The process of claim 1 wherein the air rectifying column is the low-pressure column of a double rectifying colomn, and vapor in the top of the medium-pressure column of said double rectifying column indirectly transfers heat to liquid in the sump of said low-pressure column.
Claim 4
Dependent Claim
34 words
The process of claim 4 wherein the adjustment of the discharge of liquid oxygen into the top of the concentrating rectifying column provides a liquid-to-vapor ratio in the range of about 0.05 to 0.2.
Claim 5
Dependent Claim
90 words
The process of claim 5 wherein the indirect transfer of heat from vapor to liquid is conducted outside the low-pressure and medium-pressure columns and effects partial vaporization of said liquid, the partially vaporized liquid is passed to below the bottom tray in the concentrating rectifying column as the stream of oxygen containing increased quantities of krypton, xenon and hydrocarbons, and part of the vapor of said partially vaporized liquid is passed from below the bottom tray in said concentrating rectifying column to below the bottom tray in said low-pressure column.
Claim 6
Dependent Claim
124 words
In an air rectifying plant wherein liquid oxygen collects in the sump of a rectifying column and is reboiled, the improvement of means for concentrating krypton and xenon in said liquid oxygen in said sump which comprises an auxiliary rectifying column, first means for drawing liquid from a level just below the bottom tray in said rectifying column and introducing said liquid on the top tray in said auxiliary rectifying column, second means for passing a stream drawn from a lower level below said bottom tray to below the bottom tray in said auxiliary rectifying column, an outlet at the top of said auxiliary rectifying column for gaseous oxygen, and a valved pipe connecting the bottom of said auxiliary rectifying column to said sump.
Claim 7
Dependent Claim
22 words
The air rectifying plant of claim 7 wherein the first means for drawing liquid includes a pump with a variable pumping rate.
References Cited (Backward Citations)
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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) | 1976-08-13 | 1977-02-12 | 1977-08-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-13 | 1981-02-12 | 1981-08-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-13 | 1985-02-12 | 1985-08-14 | $7700.00 | Window Closed / Lapsed |