US3683634A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Prefractionation with subsequent recombination if feed in double column rectifier
Assignee: Individual
•
Filing: 1969-08-12
•
Granted: 1972-08-15
•
Expires: 1989-08-12
Abstract
Abstract A portion of a pressurized gas mixture containing a component like carbon dioxide which solidifies during cooling is separated into a fraction substantially free of such component and a fraction enriched in such component. The remaining portion of the gas mixture and the two fractions are then fed to different levels of a fractionation zone with the fraction substantially free of such component entering at the highest level and the other fraction at the lowest level.
Inventors
- 👤 Martin Streich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 05:14
CPC Classifications
F; F25; F25J; F25J3/00; F25J3/02; F25J3/0228; F25J3/0257; C; C07; C07C; C07C7/00; C07C7/04; C10; C10G; C10G5/00; C10G5/06; F25J3/0204; F25J3/0209; F25J3/0233; F25J2200/00; F25J2200/08; F25J2200/38; F25J2200/50; F25J2200/72; F25J2220/00; F25J2220/60; F25J2220/66; Y; Y02; Y02P; Y02P20/00; Y02P20/151; Y10; Y10S; Y10S62/00; Y10S62/928; Y10S62/929
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
228 words
A process for fractionating a pressurized gas mixture containing carbon dioxide in a fractionation zone having a high pressure stage and a low pressure stage, which comprises cooling said mixture containing said carbon dioxide to close to its dew point, dividing the thus cooled mixture containing said carbon dioxide into a first stream and a second stream, fractionating said first stream into a head fraction substantially free of said carbon dioxide and a bottom fraction enriched in said carbon dioxide, passing said head fraction substantially without change of pressure in indirect heat exchange with liquid in the bottom of said high pressure stage, expanding and directly introducing said bottom fraction at a low level in said high pressure stage of said fractionation zone, introducing said second stream at a second level above said low level in said high pressure stage, introducing said head fraction after said indirect heat exchange into said fractionation zone at a third level above said second level in said high pressure stage, passing liquid from the top of said high pressure stage into the top of said low pressure stage, and recovering from the top and bottom of said low pressure stage product fractions substantially free of said carbon dioxide and from the bottom of said high pressure stage a product fraction containing substantially all of said carbon dioxide originally present in said mixture.
Claim 2
Dependent Claim
228 words
A process for fractionating a pressurized gas mixture containing carbon dioxide in a fractionation zone having a high pressure stage and a low pressure stage, which comprises cooling said mixture containing said carbon dioxide to close to its dew point, dividing the thus cooled mixture containing said carbon dioxide into a first stream and a second stream, fractionating said first stream into a head fraction substantially free of said carbon dioxide and a bottom fraction enriched in said carbon dioxide, passing said head fraction substantially without change of pressure in indirect heat exchange with liquid in the bottom of said high pressure stage, expanding and directly introducing said bottom fraction at a low level in said high pressure stage of said fractionation zone, introducing said second stream at a second level above said low level in said high pressure stage, introducing said head fraction after said indirect heat exchange into said fractionation zone at a third level above said second level in said high pressure stage, passing liquid from the top of said high pressure stage into the top of said low pressure stage, and recovering from the top and bottom of said low pressure stage product fractions substantially free of said carbon dioxide and from the bottom of said high pressure stage a product fraction containing substantially all of said carbon dioxide originally present in said mixture.
Claim 3
Dependent Claim
18 words
The process of claim 1 wherein the first stream and the second stream are approximately equal in volume.
Claim 4
Dependent Claim
15 words
The process of claim 1 wherein the gas mixture is natural gas containing carbon dioxide.
Claim 5
Dependent Claim
32 words
The process of claim 1 wherein The gas mixture is natural gas containing carbon dioxide and nitrogen, and substantially pure methane product is recovered from the bottom of the low pressure stage.
Claim 6
Dependent Claim
18 words
The process of claim 4 wherein the first stream and the second stream are approximately equal in volume.
Claim 7
Dependent Claim
220 words
A process for fractionating a pressurized gas mixture containing carbon dioxide in a fractionation zone having a high pressure stage and a low pressure stage, which comprises cooling said mixture containing said carbon dioxide to close to its dew point, dividing the thus cooled mixture containing said carbon dioxide into a first stream and a second stream, fractionating said first stream into a head fraction substantially free of said carbon dioxide and a bottom fraction enriched in said carbon dioxide, passing said head fraction substantially without change of pressure in indirect heat exchange with liquid in the bottom of said high pressure stage, expanding and directly introducing said bottom fraction at a low level in said high pressure stage of said fractionation zone, introducing said second stream at a second level above said low level in said high pressure stage, introducing said head fraction after said indirect heat exchange into the middle portion of said low pressure stage, passing liquid from the top of said high pressure stage into the top of said low pressure stage, and recovering from the top and bottom of said low pressure stage product fractions substantially free of said carbon dioxide and from the bottom of said high pressure stage a product fraction containing substantially all of said carbon dioxide originally present in said mixture.
Claim 8
Dependent Claim
220 words
A process for fractionating a pressurized gas mixture containing carbon dioxide in a fractionation zone having a high pressure stage and a low pressure stage, which comprises cooling said mixture containing said carbon dioxide to close to its dew point, dividing the thus cooled mixture containing said carbon dioxide into a first stream and a second stream, fractionating said first stream into a head fraction substantially free of said carbon dioxide and a bottom fraction enriched in said carbon dioxide, passing said head fraction substantially without change of pressure in indirect heat exchange with liquid in the bottom of said high pressure stage, expanding and directly introducing said bottom fraction at a low level in said high pressure stage of said fractionation zone, introducing said second stream at a second level above said low level in said high pressure stage, introducing said head fraction after said indirect heat exchange into the middle portion of said low pressure stage, passing liquid from the top of said high pressure stage into the top of said low pressure stage, and recovering from the top and bottom of said low pressure stage product fractions substantially free of said carbon dioxide and from the bottom of said high pressure stage a product fraction containing substantially all of said carbon dioxide originally present in said mixture.
Claim 9
Dependent Claim
32 words
The process of claim 6 wherein the gas mixture is natural gas containing carbon dioxide and nitrogen, and substantially pure methane product is recovered from the bottom of the low pressure stage.
Claim 10
Dependent Claim
18 words
The process of claim 7 wherein the first stream and the second stream are approximately equal in volume.
Claim 11
Dependent Claim
18 words
The process of claim 6 wherein the first stream and the second stream are approximately equal in volume.
Claim 12
Dependent Claim
15 words
The process of claim 6 wherein the gas mixture is natural gas containing carbon dioxide.
References Cited (Backward Citations)
US2209748A
Cited
US2502251A
Cited
US2729954A
Cited
US2788646A
Cited
US3066494A
Cited
US3079759A
Cited
US3392536A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-15 | 1976-02-14 | 1976-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-15 | 1980-02-14 | 1980-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-15 | 1984-02-14 | 1984-08-15 | $7700.00 | Window Closed / Lapsed |