US3800550A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for reliquefying boil-off vapor from liquefied gas
Assignee: Chicago Bridge and Iron Co
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Filing: 1972-12-14
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Granted: 1974-04-02
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Expires: 1992-12-14
Abstract
Abstract Apparatus and processes for recondensing boil-off vapor from an insulated storage tank containing a liquefied gas, such as liquefied natural gas, so that it continues to comprise a part of the stored liquefied gas. Boil-off vapor is recondensed by refrigeration obtained from expansion of a liquefied gas stream withdrawn from the storage tank. The expanded stream, as a vapor, can be pressurized by feeding it to the suction side of an ejector to which a high pressure gas is fed to supply the motive force. Alternatively, a vapor stream derived from the stored liquefied gas can be fed to a venturi ejector as the motive force to pressurize boil-off vapor fed from the storage tank to the suction side of the ejector. The combined stream from the ejector, after being refrigerated by the withdrawn liquefied gas stream, is expanded to the tank vapor space to cool the tank contents. Under either system, liquefied gas stored at about atmospheric pressure can be vaporized and distributed at a pressure greater than atmospheric pressure.
Inventors
- 👤 T Delahunty
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:07
CPC Classifications
F; F25; F25J; F25J1/00; F25J1/0002; F25J1/0022; F25J1/0025; F25J1/003; F25J1/0032; F25J1/0045; F25J1/02; F25J1/0201; F25J1/0221; F17; F17C; F17C2227/00; F17C2227/03; F17C2227/0337; F17C2227/0358; F17C2265/00; F17C2265/03; F17C2265/032; F17C2265/033; F25J2210/00; F25J2210/62; F25J2235/00; F25J2235/60; F25J2240/00; F25J2240/60; F25J2290/00; F25J2290/34; F25J2290/62
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
124 words
A process which comprises: removing a first stream of liquefied gas from an insulated storage tank and expanding it to a low pressure cold vapor stream; removing a second stream of liquefied gas from the storage tank and passing it in heat exchange relationship with the cold first stream to cool said second liquefied gas stream; returning the cooled second liquefied gas stream to the vapor space of the storage tank to cool the tank contents; feeding the now warmed low pressure first stream into inspiration communication wth a venturi ejector; and feeding a high pressure third stream of gas through a venturi ejector to inspirate and pressurize the low pressure vapor from the first stream and admix therewith to form an exit stream.
Claim 2
Dependent Claim
124 words
A process which comprises: removing a first stream of liquefied gas from an insulated storage tank and expanding it to a low pressure cold vapor stream; removing a second stream of liquefied gas from the storage tank and passing it in heat exchange relationship with the cold first stream to cool said second liquefied gas stream; returning the cooled second liquefied gas stream to the vapor space of the storage tank to cool the tank contents; feeding the now warmed low pressure first stream into inspiration communication wth a venturi ejector; and feeding a high pressure third stream of gas through a venturi ejector to inspirate and pressurize the low pressure vapor from the first stream and admix therewith to form an exit stream.
Claim 3
Dependent Claim
17 words
A process according to claim 1 in which the composition of all the streams is natural gas.
Claim 4
Dependent Claim
92 words
A process which comprises: removing a first stream of liquefied gas from an insulated storage tank and expanding it to a low pressure cold stream; removing a second stream of liquefied gas from the storage tank and passing it in heat exchange relationship with the cold first stream to cool said second liquefied gas stream; returning the cooled second liquefied gas stream to the vapor space of the storage tank to cool the tank contents; and compressing and further heating the low pressure first stream and feeding it to a distribution line.
Claim 5
Dependent Claim
92 words
A process which comprises: removing a first stream of liquefied gas from an insulated storage tank and expanding it to a low pressure cold stream; removing a second stream of liquefied gas from the storage tank and passing it in heat exchange relationship with the cold first stream to cool said second liquefied gas stream; returning the cooled second liquefied gas stream to the vapor space of the storage tank to cool the tank contents; and compressing and further heating the low pressure first stream and feeding it to a distribution line.
Claim 6
Dependent Claim
17 words
A process according to claim 3 in which the composition of all the streams is natural gas.
Claim 7
Dependent Claim
180 words
In combination: an enclosed insulated storage tank for a liquefied gas; a first conduit communicating with the tank interior and a heat exchanger outside thereof for removing liquefied gas from the tank and sending it to the heat exchanger to be cooled; a second conduit from the heat exchanger to the vapor space of the tank for supplying cooled liquefied gas thereto to condense boil-off vapor; a third conduit communicating with the tank interior and an expansion valve for removing liquefied gas from the tank and expanding it through the valve; a fourth conduit communicating with the expansion valve and the heat exchanger for supplying the expanded gas stream as a refrigeration source to the heat exchanger; a fifth conduit communicating with the heat exchanger and the suction side of a venturi ejector for supplying the expanded gas stream at low pressure to the ejector; a sixth conduit communicating with the ejector for supplying a high pressure gas stream thereto; and a seventh conduit in communication with the exit side of the ejector to receive the combined gas stream therefrom.
Claim 8
Dependent Claim
180 words
In combination: an enclosed insulated storage tank for a liquefied gas; a first conduit communicating with the tank interior and a heat exchanger outside thereof for removing liquefied gas from the tank and sending it to the heat exchanger to be cooled; a second conduit from the heat exchanger to the vapor space of the tank for supplying cooled liquefied gas thereto to condense boil-off vapor; a third conduit communicating with the tank interior and an expansion valve for removing liquefied gas from the tank and expanding it through the valve; a fourth conduit communicating with the expansion valve and the heat exchanger for supplying the expanded gas stream as a refrigeration source to the heat exchanger; a fifth conduit communicating with the heat exchanger and the suction side of a venturi ejector for supplying the expanded gas stream at low pressure to the ejector; a sixth conduit communicating with the ejector for supplying a high pressure gas stream thereto; and a seventh conduit in communication with the exit side of the ejector to receive the combined gas stream therefrom.
Claim 9
Dependent Claim
48 words
The combination of claim 5 in which: an eighth conduit communicates with the sixth conduit and with a second venturi ejector; the seventh conduit communicates with the suction side of the second venturi ejector; and a ninth conduit communicates with the exit side of the second venturi ejector.
Claim 10
Dependent Claim
25 words
The combination of claim 5 in which the sixth conduit has valve means for blocking and regulating flow of the high pressure gas stream therethrough.
Claim 11
Dependent Claim
12 words
The combination of claim 5 including a pump in the first conduit.
Claim 12
Dependent Claim
77 words
In combination: an enclosed insulated storage tank for a liquefied gas; means for removing liquefied gas from the storage tank, feeding it through a heat exchanger to be cooled and delivering the cooled liquefieD gas to the vapor space of the tank in order to reduce the vapor pressure therein; and means for removing liquefied gas from the storage tank, expanding it and passing it as a refrigeration stream through the heat exchanger to provide refrigeration thereto.
Claim 13
Dependent Claim
77 words
In combination: an enclosed insulated storage tank for a liquefied gas; means for removing liquefied gas from the storage tank, feeding it through a heat exchanger to be cooled and delivering the cooled liquefieD gas to the vapor space of the tank in order to reduce the vapor pressure therein; and means for removing liquefied gas from the storage tank, expanding it and passing it as a refrigeration stream through the heat exchanger to provide refrigeration thereto.
Claim 14
Dependent Claim
35 words
The combination of claim 9 having means for feeding the refrigeration stream from the heat exchanger to the suction side of a venturi ejector, and means for supplying a high pressure gas to the ejector.
Claim 15
Dependent Claim
147 words
A process which comprises: removing a first stream of liquefied gas from an insulated storage tank and expanding it to a low pressure cold stream; removing a second stream of liquefied gas from the storage tank and passing it in heat exchange relationship with the cold first stream to cool said second liquefied gas stream; returning the cooled second liquefied gas stream to the vapor space of the storage tank to cool the tank contents; feeding the now warmed low pressure first stream into inspiration communication with a venturi ejector; feeding a high pressure third stream of gas through a ventrui ejector to inspirate and pressurize the low pressure vapor from the first stream and admix therewith to form an exit stream; and passing the exit stream to, and inspirating it through, a second venturi ejector by passage of part of the third stream of gas therethrough.
Claim 16
Dependent Claim
147 words
A process which comprises: removing a first stream of liquefied gas from an insulated storage tank and expanding it to a low pressure cold stream; removing a second stream of liquefied gas from the storage tank and passing it in heat exchange relationship with the cold first stream to cool said second liquefied gas stream; returning the cooled second liquefied gas stream to the vapor space of the storage tank to cool the tank contents; feeding the now warmed low pressure first stream into inspiration communication with a venturi ejector; feeding a high pressure third stream of gas through a ventrui ejector to inspirate and pressurize the low pressure vapor from the first stream and admix therewith to form an exit stream; and passing the exit stream to, and inspirating it through, a second venturi ejector by passage of part of the third stream of gas therethrough.
Claim 17
Dependent Claim
16 words
A process according to claim 11 in which the composition of all streams is natural gas.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-04-01 | 1977-10-01 | 1978-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-01 | 1981-10-01 | 1982-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-01 | 1985-10-01 | 1986-04-02 | $7700.00 | Window Closed / Lapsed |