Patent US4666481A successfully refreshed from Google Patents.
US4666481A
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Process for producing liquid helium
Assignee: Praxair Technology Inc
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Filing: 1986-03-10
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Granted: 1987-05-19
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Expires: 2006-03-10
Abstract
Abstract A process for the production of liquid helium wherein refrigeration from helium-containing feed is employed to cool helium liquefier recycle and thus reduce helium liquefier power requirements.
Inventors
- 👤 Raymond R. Olson, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 05:10
CPC Classifications
F; F25; F25J; F25J3/00; F25J3/06; F25J3/063; F25J3/0685; F25J3/069; F25J1/00; F25J1/0002; F25J1/0005; F25J1/0007; F25J1/003; F25J1/0032; F25J1/0035; F25J1/0037; F25J1/004; F25J1/02; F25J1/0221; F25J1/0224; F25J1/0228; F25J1/0235; F25J1/0237; F25J1/0243; F25J1/0244; F25J1/0245; F25J1/0249; F25J1/025; F25J3/0605; F25J3/061; F25J3/066; F25J3/08; F25J2205/00; F25J2205/40; F25J2205/60; F25J2205/82; F25J2210/00; F25J2210/02; F25J2215/00; F25J2215/04; F25J2215/30; F25J2220/00; F25J2220/02; F25J2220/42; F25J2220/44; F25J2245/00; F25J2245/02; F25J2260/00; F25J2260/20; F25J2260/42; F25J2260/44; F25J2270/00; F25J2270/04; F25J2270/06
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
130 words
A process for producing liquid helium comprising: (a) providing a feed vapor comprising at least 20 percent helium at a temperature of 150° K. or less; (b) cooling and partially condensing the feed to produce helium vapor and liquid remainder; (c) warming helium vapor by indirect heat exchange with cooling feed of step (b); (d) upgrading the helium vapor to liquefier grade helium vapor; (e) passing liquefier grade helium vapor to a helium liquefier; (f) partially condensing liqueifer grade helium vapor in the helium liquefier to produce liquid helium and helium recycle vapor; (g) compressing helium recycle vapor; (h) cooling at least some compressed helium recycle vapor by indirect heat exchange with warming helium vapor of step (c); and (i) returning cooled, compressed helium recycle vapor to the helium liquefier.
Claim 2
Dependent Claim
130 words
A process for producing liquid helium comprising: (a) providing a feed vapor comprising at least 20 percent helium at a temperature of 150° K. or less; (b) cooling and partially condensing the feed to produce helium vapor and liquid remainder; (c) warming helium vapor by indirect heat exchange with cooling feed of step (b); (d) upgrading the helium vapor to liquefier grade helium vapor; (e) passing liquefier grade helium vapor to a helium liquefier; (f) partially condensing liqueifer grade helium vapor in the helium liquefier to produce liquid helium and helium recycle vapor; (g) compressing helium recycle vapor; (h) cooling at least some compressed helium recycle vapor by indirect heat exchange with warming helium vapor of step (c); and (i) returning cooled, compressed helium recycle vapor to the helium liquefier.
Claim 3
Dependent Claim
16 words
The process of claim 1 wherein the feed vapor comprises from 30 to 60 percent helium.
Claim 4
Dependent Claim
24 words
The process of claim 1 wherein the feed vapor is taken from a nitrogen rejection unit and contains at least about 30 percent nitrogen.
Claim 5
Dependent Claim
27 words
The process of claim 1 wherein a helium-containing stream at a temperature exceeding 150° K. is combined with the feed vapor prior to or during step (b).
Claim 6
Dependent Claim
38 words
The process of claim 1 wherein the warmed helium vapor of step (c) is combined with air and the combined stream heated and passed over a catalyst bed wherein hydrogen which may be present is oxidized to water.
Claim 7
Dependent Claim
45 words
The process of claim 5 wherein the output from the catalyst bed is passed to a pressure swing adsorption process to produce liquefier grade helium vapor which is passed to the helium liquefier as the liquefier grade helium vapor of step (e), and tail gas.
Claim 8
Dependent Claim
19 words
The process of claim 6 wherein tail gas is reintroduced to feed vapor prior to or during step (b).
Claim 9
Dependent Claim
24 words
The process of claim 1 wherein the partial condensation of the liquefier grade helium vapor of step (f) is carried out by work expansion.
Claim 10
Dependent Claim
18 words
The process of claim 8 wherein the work expansion produces vapor having at least two different pressure levels.
Claim 11
Dependent Claim
26 words
The process of claim 1 wherein some of the compressed helium recycle vapor is returned directly to the helium liquefier without undergoing cooling of step (h).
Claim 12
Dependent Claim
26 words
The process of claim 1 wherein liquid remainder is partially vaporized and the vapor is reintroduced to the feed vapor prior to or during step (b).
Claim 13
Dependent Claim
27 words
The process of claim 11 wherein the liquid remainder from the said partial vaporization is itself partially vaporized and at least some of the vapor is recovered.
Claim 14
Dependent Claim
12 words
The process of claim 12 wherein the recovered vapor comprises primarily nitrogen.
Claim 15
Dependent Claim
16 words
The process of claim 12 wherein some of said vapor is liquefied and recovered as liquid.
Claim 16
Dependent Claim
11 words
The process of claim 14 wherein said liquid comprises primarily nitrogen.
Claim 17
Dependent Claim
40 words
The process of claim 1 wherein the ratio of the flowrate of the compressed helium recycle vapor which undergoes the cooling of step (h) to the flowrate of the feed vapor is in the range of from 0.8 to 1.2.
Claim 18
Dependent Claim
22 words
The process of claim 1 wherein the upgrading of the helium vapor to liquefier grade helium vapor is by pressure swing adsorption.
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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) | 1990-05-18 | 1990-11-17 | 1991-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-05-18 | 1994-11-17 | 1995-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-05-18 | 1998-11-17 | 1999-05-19 | $7700.00 | Window Closed / Lapsed |