US3695052A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Concentration control for multiple stage absorption refrigeration systems
Assignee: Carrier Corp
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Filing: 1971-07-28
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Granted: 1972-10-03
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Expires: 1991-07-28
Abstract
Abstract A two-stage air cooled lithium bromide absorption refrigeration system having a generator, a refrigerant condenser, a high pressure absorber coupled with a high temperature evaporator, a low pressure absorber coupled with a low temperature evaporator and an air conditioning fan coil unit for passing cooled refrigerant in heat exchange with ambient air is provided with a concentration control system for automatically diluting the absorbent solution under conditions of either low ambient temperatures or an inadequately purged low pressure absorber. The concentration control includes a refrigerant storage tank connected directly to the refrigerant condenser. Intermediate strength absrobent solution discharged from the low pressure absorber is passed through a heat exchanger in the refrigerant storage tank, in heat exchange relation with refrigerant therein, to the high pressure absorber. A refrigerant overflow passage is provided from a refrigerant sump to a location containing absorbent solution. Ambient air passes serially over the low pressure absorber and then over the refrigerant condenser so that when the low pressure absorber is poorly purged or the ambient air temperature is relatively low, these events will be reflected by a drop in the intermediate solution temperature passing through the refrigerant storage tank and a simultaneous drop in the condensing temperature. Consequently, the difference in pressure between the refirgerant storage tank and the condenser will drop and refrigerant will pass into the system from the storage tank and will cause the refrigerant level in the sump to overflow into absorbent soulution through the refrigerant overflow passage to prevent solidification.
Inventors
- 👤 Charles K Griffin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:33
CPC Classifications
F; F25; F25B; F25B15/00; F25B15/008; F25B15/02; F25B15/06; F25B2315/00; F25B2315/001; Y; Y02; Y02A; Y02A30/00; Y02A30/27; Y02B; Y02B30/00; Y02B30/62
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
337 words
An absorption refrigeration system comprising: A. a generator for concentrating absorbent solution by heating the solution and vaporizing refrigerant therefrom; B. a refrigerant condenser for condensing refrigerant vapor formed in the generator; C. a low temperature evaporator for evaporating refrigerant at a relatively low temperature to produce a refrigeration effect; D. a low pressure absorber for absorbing refrigerant vapor evaporated in the low temperature evaporator into absorbent solution; E. a high temperature evaporator for evaporating refrigerant at a relatively higher temperature to produce a refrigeration effect; F. a high pressure absorber for absorbing refrigerant vapor evaporated in the high temperature evaporator into absorbent solution; and G. means to serially pass a cooling medium in heat exchange relation with absorbent solution in said low pressure absorber and thence into heat exchange relation with refrigerant in said condenser; wherein the improvement comprises: H. concentration control means for varying the concentration of absorbent solution in the system, said concentration control means including: 1. a refrigerant storage tank for accumulating and discharging liquid refrigerant; 2. concentration control passage means in said system, including refrigerant condensate passage means directly connecting said refrigerant storage tank with said condenser for passing sufficient liquid refrigerant from the condenser to said refrigerant storage tank to automatically balance the pressure in said condenser with the pressure and liquid head of refrigerant in the storage tank, and overflow passage means for passing liquid refrigerant into absorbent solution for mixture therewith when refrigerant is discharged from said refrigerant storage tank; and 3. intermediate solution passage means for passing intermediate strength absorbent solution from said low pressure absorber in direct heat exchange relation with refrigerant in said refrigerant storage tank to said high pressure absorber, whereby the pressure in said refrigerant storage tank is a function of the temperature of said intermediate solution, and the quantity of refrigerant stored in said storage tank and the dilution of the absorbent solution automatically varies as a function of the difference between the condensing temperature and the intermediate solution temperature of said system.
Claim 2
Dependent Claim
337 words
An absorption refrigeration system comprising: A. a generator for concentrating absorbent solution by heating the solution and vaporizing refrigerant therefrom; B. a refrigerant condenser for condensing refrigerant vapor formed in the generator; C. a low temperature evaporator for evaporating refrigerant at a relatively low temperature to produce a refrigeration effect; D. a low pressure absorber for absorbing refrigerant vapor evaporated in the low temperature evaporator into absorbent solution; E. a high temperature evaporator for evaporating refrigerant at a relatively higher temperature to produce a refrigeration effect; F. a high pressure absorber for absorbing refrigerant vapor evaporated in the high temperature evaporator into absorbent solution; and G. means to serially pass a cooling medium in heat exchange relation with absorbent solution in said low pressure absorber and thence into heat exchange relation with refrigerant in said condenser; wherein the improvement comprises: H. concentration control means for varying the concentration of absorbent solution in the system, said concentration control means including: 1. a refrigerant storage tank for accumulating and discharging liquid refrigerant; 2. concentration control passage means in said system, including refrigerant condensate passage means directly connecting said refrigerant storage tank with said condenser for passing sufficient liquid refrigerant from the condenser to said refrigerant storage tank to automatically balance the pressure in said condenser with the pressure and liquid head of refrigerant in the storage tank, and overflow passage means for passing liquid refrigerant into absorbent solution for mixture therewith when refrigerant is discharged from said refrigerant storage tank; and 3. intermediate solution passage means for passing intermediate strength absorbent solution from said low pressure absorber in direct heat exchange relation with refrigerant in said refrigerant storage tank to said high pressure absorber, whereby the pressure in said refrigerant storage tank is a function of the temperature of said intermediate solution, and the quantity of refrigerant stored in said storage tank and the dilution of the absorbent solution automatically varies as a function of the difference between the condensing temperature and the intermediate solution temperature of said system.
Claim 3
Dependent Claim
78 words
concentration control passage means in said system, including refrigerant condensate passage means directly connecting said refrigerant storage tank with said condenser for passing sufficient liquid refrigerant from the condenser to said refrigerant storage tank to automatically balance the pressure in said condenser with the pressure and liquid head of refrigerant in the storage tank, and overflow passage means for passing liquid refrigerant into absorbent solution for mixture therewith when refrigerant is discharged from said refrigerant storage tank; and
Claim 4
Dependent Claim
78 words
concentration control passage means in said system, including refrigerant condensate passage means directly connecting said refrigerant storage tank with said condenser for passing sufficient liquid refrigerant from the condenser to said refrigerant storage tank to automatically balance the pressure in said condenser with the pressure and liquid head of refrigerant in the storage tank, and overflow passage means for passing liquid refrigerant into absorbent solution for mixture therewith when refrigerant is discharged from said refrigerant storage tank; and
Claim 5
Dependent Claim
84 words
An absorption refrigeration system as defined in claim 1 wherein said overflow passage means includes a refrigerant overflow passage extending from a refrigerant sump to a location in said system containing absorbent solution, and said refrigerant storage tank is located in said system so that discharge of refrigerant from said refrigerant storage tank causes the level of refrigerant in said refrigerant sump to rise and overflow through said refrigerant overflow passage into said location containing absorbent solution and to mix with the absorbent solution.
Claim 6
Dependent Claim
87 words
intermediate solution passage means for passing intermediate strength absorbent solution from said low pressure absorber in direct heat exchange relation with refrigerant in said refrigerant storage tank to said high pressure absorber, whereby the pressure in said refrigerant storage tank is a function of the temperature of said intermediate solution, and the quantity of refrigerant stored in said storage tank and the dilution of the absorbent solution automatically varies as a function of the difference between the condensing temperature and the intermediate solution temperature of said system.
Claim 7
Dependent Claim
87 words
intermediate solution passage means for passing intermediate strength absorbent solution from said low pressure absorber in direct heat exchange relation with refrigerant in said refrigerant storage tank to said high pressure absorber, whereby the pressure in said refrigerant storage tank is a function of the temperature of said intermediate solution, and the quantity of refrigerant stored in said storage tank and the dilution of the absorbent solution automatically varies as a function of the difference between the condensing temperature and the intermediate solution temperature of said system.
Claim 8
Dependent Claim
32 words
An absorption refrigeration system as defined in claim 1 including a restricted vent passage for venting relatively noncondensible gases from said refrigerant storage tank to a low pressure region in the system.
Claim 9
Dependent Claim
31 words
An absorption refrigeration system as defined in claim 1 wherein said refrigerant condensate passage means comprises a depending loop connecting the liquid header of the condenser with the refrigerant storage tank.
Claim 10
Independent Claim
280 words
A method of producing refrigeration and operating an absorption refrigeration system having a generator, a refrigerant condenser, a low temperature evaporator, a low pressure absorber, a high temperature evaporator, a high pressure absorber, and a refrigerant storage tank, which comprises: A. heating weak absorbent solution in the generator to concentrate it by vaporizing refrigerant therefrom; B. condensing in the refrigerant condenser refrigerant vapor formed in the generator; C. evaporating liquid refrigerant in the high temperature evaporator and in the low temperature evaporator to produce refrigeration; D. absorbing refrigerant vapor formed in the high pressure absorber, and absorbing refrigerant vapor formed in the low temperature evaporator into absorbent solution in the low pressure absorber; E. passing a cooling medium serially into heat exchange relation with absorbent solution in the low pressure absorber and then into heat exchange relation with refrigerant vapor in said refrigerant condenser; wherein the improvement comprises: F. passing liquid refrigerant from the refrigerant condenser to the refrigerant storage tank in an amount sufficient to balance the pressure difference between the refrigerant condenser and the storage tank; G. varying the quantity of refrigerant stored in the refrigerant storage tank by passing intermediate strength absorbent solution from the low pressure absorber to the high pressure absorber in heat exchange relation with refrigerant in the storage tank to thereby vary the refrigerant pressure in the tank; and H. mixing liquid refrigerant with absorbent solution to dilute the absorbent solution by overflowing liquid refrigerant from a location containing refrigerant into a location containing absorbent solution upon discharge of refrigerant liquid from the refrigerant storage tank due to a drop in the pressure difference between said refrigerant condenser and said refrigerant storage tank.
Claim 11
Independent Claim
280 words
A method of producing refrigeration and operating an absorption refrigeration system having a generator, a refrigerant condenser, a low temperature evaporator, a low pressure absorber, a high temperature evaporator, a high pressure absorber, and a refrigerant storage tank, which comprises: A. heating weak absorbent solution in the generator to concentrate it by vaporizing refrigerant therefrom; B. condensing in the refrigerant condenser refrigerant vapor formed in the generator; C. evaporating liquid refrigerant in the high temperature evaporator and in the low temperature evaporator to produce refrigeration; D. absorbing refrigerant vapor formed in the high pressure absorber, and absorbing refrigerant vapor formed in the low temperature evaporator into absorbent solution in the low pressure absorber; E. passing a cooling medium serially into heat exchange relation with absorbent solution in the low pressure absorber and then into heat exchange relation with refrigerant vapor in said refrigerant condenser; wherein the improvement comprises: F. passing liquid refrigerant from the refrigerant condenser to the refrigerant storage tank in an amount sufficient to balance the pressure difference between the refrigerant condenser and the storage tank; G. varying the quantity of refrigerant stored in the refrigerant storage tank by passing intermediate strength absorbent solution from the low pressure absorber to the high pressure absorber in heat exchange relation with refrigerant in the storage tank to thereby vary the refrigerant pressure in the tank; and H. mixing liquid refrigerant with absorbent solution to dilute the absorbent solution by overflowing liquid refrigerant from a location containing refrigerant into a location containing absorbent solution upon discharge of refrigerant liquid from the refrigerant storage tank due to a drop in the pressure difference between said refrigerant condenser and said refrigerant storage tank.
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) | 1975-10-03 | 1976-04-03 | 1976-10-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-03 | 1980-04-03 | 1980-10-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-03 | 1984-04-03 | 1984-10-03 | $7700.00 | Window Closed / Lapsed |