US4676694A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process and installation for the congelation of grounds by means of a cryogenic liquid
Assignee: L'AR LIQUIDE
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Filing: 1985-05-29
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Granted: 1987-06-30
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Expires: 2005-05-29
Abstract
Abstract The injection of liquid nitrogen into the probe (2) is regulated in an on-off manner so as to maintain the temperature of the ground at the coldest point above a value within the range of between -140° C. and -160° C. so as to cause calefaction of the liquid nitrogen. The liquid nitrogen is alternately injected into the central passage (9) and into the annular passage (11) of the probe, these passages being thermally insulated from each other.
Inventors
- 👤 Pierre Karinthi
- 👤 Maurice Gardent
- 👤 Colette Regnier
- 👤 Jean Tuccella
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:31
CPC Classifications
E; E02; E02D; E02D3/00; E02D3/11; E02D3/115; E02D19/00; E02D19/06; E02D19/12; E02D19/14
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
107 words
A process of congelation of the ground by injection of a cryogenic liquid, in particular liquid nitrogen, in at least one congelation probe driven into the ground and having an outer wall, said process comprising regulating the injection of the cryogenic liquid in such manner as to maintain the temperature of the ground in the neighborhood of the probe, throughout the length of the probe, above a predetermined limit value, said limit value being higher by at least about 35° C. than the boiling temperature of the cryogenic liquid, and to effect heat exchange between the liquid and the probe wall always through a gaseous calefaction layer.
Claim 2
Dependent Claim
107 words
A process of congelation of the ground by injection of a cryogenic liquid, in particular liquid nitrogen, in at least one congelation probe driven into the ground and having an outer wall, said process comprising regulating the injection of the cryogenic liquid in such manner as to maintain the temperature of the ground in the neighborhood of the probe, throughout the length of the probe, above a predetermined limit value, said limit value being higher by at least about 35° C. than the boiling temperature of the cryogenic liquid, and to effect heat exchange between the liquid and the probe wall always through a gaseous calefaction layer.
Claim 3
Dependent Claim
26 words
A process according to claim 1, wherein the cryogenic liquid is liquid nitrogen and said limit value is between about -140° C. and about -160° C.
Claim 4
Dependent Claim
40 words
A process according to claim 1, comprising interrupting the injection of cryogenic liquid when said limit value is reached and resuming said injection when the temperature of the ground at the coldest point has risen to a second limit value.
Claim 5
Dependent Claim
44 words
A process according to claim 1, comprising regulating the rate of flow of cryogenic liquid during the injection periods in such manner as to obtain a temperature of the gas as it issues from the probe in the neighbourhood of a second predetermined value.
Claim 6
Dependent Claim
23 words
A process according to claim 4, wherein the cryogenic liquid is liquid nitrogen and said predetermined value is equal to about -70° C.
Claim 7
Dependent Claim
55 words
A process according to claim 1, comprising employing a probe comprising a central passage and an annular passage that communicate with each other at the lower end of the probe, and alternating periods of injection of the cryogenic liquid into the central passage and periods of injection of the cryogenic liquid into the annular passage.
Claim 8
Dependent Claim
78 words
A process of congelation of the ground by injection of a cryogenic liquid, in particular liquid nitrogen, in at least one congelation probe driven into the ground, said process comprising employing a probe comprising a central passage and an annular passage that communicate with each other at the lower end of the probe, and alternating periods of injection of the cryogenic liquid into the central passage and periods of injection of the cryogenic liquid into the annular passage.
Claim 9
Dependent Claim
78 words
A process of congelation of the ground by injection of a cryogenic liquid, in particular liquid nitrogen, in at least one congelation probe driven into the ground, said process comprising employing a probe comprising a central passage and an annular passage that communicate with each other at the lower end of the probe, and alternating periods of injection of the cryogenic liquid into the central passage and periods of injection of the cryogenic liquid into the annular passage.
References Cited (Backward Citations)
GB642058A
Cited
US3220470A
Cited
US3267680A
Cited
FR2041356A5
Cited
FR2113980A1
Cited
US4403459A
Cited
DE3112291A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-06-29 | 1990-12-29 | 1991-06-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-06-29 | 1994-12-29 | 1995-06-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-06-29 | 1998-12-29 | 1999-06-30 | $7700.00 | Window Closed / Lapsed |