GB1580432A - Refrigeration apparatus - Google Patents
Refrigeration apparatus Download PDFInfo
- Publication number
- GB1580432A GB1580432A GB20442/76A GB2044276A GB1580432A GB 1580432 A GB1580432 A GB 1580432A GB 20442/76 A GB20442/76 A GB 20442/76A GB 2044276 A GB2044276 A GB 2044276A GB 1580432 A GB1580432 A GB 1580432A
- Authority
- GB
- United Kingdom
- Prior art keywords
- adsorption
- refrigerant
- generation unit
- condenser
- heat
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B17/00—Sorption machines, plants or systems, operating intermittently, e.g. absorption or adsorption type
- F25B17/08—Sorption machines, plants or systems, operating intermittently, e.g. absorption or adsorption type the absorbent or adsorbent being a solid, e.g. salt
- F25B17/083—Sorption machines, plants or systems, operating intermittently, e.g. absorption or adsorption type the absorbent or adsorbent being a solid, e.g. salt with two or more boiler-sorbers operating alternately
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B25/00—Machines, plants or systems, using a combination of modes of operation covered by two or more of the groups F25B1/00 - F25B23/00
- F25B25/02—Compression-sorption machines, plants, or systems
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B49/00—Arrangement or mounting of control or safety devices
- F25B49/04—Arrangement or mounting of control or safety devices for sorption type machines, plants or systems
- F25B49/046—Operating intermittently
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A30/00—Adapting or protecting infrastructure or their operation
- Y02A30/27—Relating to heating, ventilation or air conditioning [HVAC] technologies
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
- Y02B30/62—Absorption based systems
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Mechanical Engineering (AREA)
- Thermal Sciences (AREA)
- General Engineering & Computer Science (AREA)
- Sorption Type Refrigeration Machines (AREA)
Description
(54) REFRIGERATION APPARATUS
(71) We, THE BRITISH PETROLEUM
COMPANY LIMITED, of Britannic House,
Moor Lane, London, EC2Y 9BU, a British company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The present invention relates to refrigeration systems, and particularly to refrigeration systems driven by solar radiation.
Most conventional refrigeration systems utilise the physical properties of low boiling liquids or liquefied gases, known as refrigerants, such as ammonia, ethyl chloridenor fluoro hydrocarbons (Freons*), to achieve the desired cooling effect. A cyclic operation is used in which the liquid refrigerant is caused to evaporate through an expansion valve, the heat needed for evaporation being extracted from the surrounding area the temperature of which is thereby lowered. The refrigerant is then caused to condense giving off heat in the process, and the cycle of events is then repeated.Condensation of the refrigerant vapour may be achieved using a mechanical compressor or, in the absorption system, by allowing the vapour to dissolve in a solvent to form a concentrated solution; this is then heated to evaporate refrigerant vapour until the partial pressure of the vapour is high enough to cause it to condense in a condenser. Whichever system is used a
source of energy is required, either to drive a compressor or to provide heat to evaporate
the refrigerant from solution.
The present invention comprises a refrigeration system containing a low boiling refrigerant, and having
(1) two adsorption/generation units containing a solid adsorbent chargeable with the refrigerant,
(2) a condenser the inlet of which is connectable alternately to each adsorption/geneartion unit and in which refrigerant vapour desorbed from an adsorption/generation unit is caused to condense, and associated therewith an expansion valve for discharging the condensed refrigerant,
(3) an evaporator/cooler the inlet of which is connected via the expansion valve to the condenser and in which the condense refrigerant is allowed to evaporate thereby cooling the evaporator/cooler, and the outlet of which is connectable alternately to each adsorption/ generation unit,
(4) heating means for alternately heating each adsorbtion/generation unit,
(5) heat removal means for removing heat from the condenser and for alternately cooling each adsorption/generation unit,
(6) controlling means for producing a continuous alternating operational cycle in which refrigerant is transferred from one adsorption/generation unit to the other unit and then in the reverse direction, whereby firstly one unit is connected to the condenser and is heated to desorb the refrigerant while the other unit is connected to the evaporator/ cooler and is cooled to adsorb refrigerant vapour, and secondly in a reverse operation the replenished unit is connected to the condenser and is heated while the depleted unit is connected to the evaporator/cooler and is cooled, wherein the controlling means operates in response to the change in weight of one or both of the adsorption/generation units caused by the adsorption/desorption of refrigerant.
The refrigerants which may be used in the refrigeration system of the present invention are those low boiling liquids or liquefied gases conventionally used as refrigerants which are adsorbable by the solid adsorbent contained in the adsorption/generation units.
Suitable refrigerants are for instance ammonia, ethyl chloride, fluoro hydrocarbons, alkanes up to C14 alkanes and cr-alcohols such as methanol and ethanol. It is preferred to use a fluorohydrocarbon such as trichlorofluoromethane.
The adsorption/generation units are charged with a solid adsorbent which may be for instance silica gel, carbon, molecular sieves or zeolites, or activated alumina. Each adsorption/generation unit is connected to *Freon is a registered Trade Mark.
the inlet of the condenser, for instance by means of a pipe in which is located a valve controlled by the controlling means. The adsorption/generation units are also similarly connected to the outlet of the evaporator/ cooler, for instance by means of pipes in which are located valves controlled by the controlling means. The adsorption/generation units are also similarly connected to the outlet of the evaporator/cooler, for instance by means of pipes in which are located valves controlled by the controlling means.
The condenser, expansion valve and evaporator/cooler may be constructed as in conventional refrigeration equipment.
The heating means for alternately heating each adsorption/generation unit to desorb the refrigerant can utilise any convenient source of heat and may comprise for instance electrical heating means. It is however preferred to use solar radiation as the source of heat. Apparatus specifically designed for operation by solar heat input will comprise adsorption/generation units which have the form of solar heaters in which the adsorbent and refrigerant are contained and to which are attached in good thermal contact the heat removal means, which may comprise for instance a system of pipes containing circulating cooling water.The heat removal means for removing heat from the adsorption/ generation units may be associated with the means for removing heat from the condenser and may comprise for instance a system of pipes containing circulating cooling water arranged to cool first the condenser and then one or other of the two adsorption/generation units. Such a system of pipes can embody valves for directing the circulating cooling water to one or other of the adsorption/generation units, the valves being controlled by the controlling means. The cooling circuit also contains a heat rejector which may be for instance a heat exchanger associated with a domestic hot water system.
The temperature range over which a large proportion of the refrigerant is desorbed from the adsorbent can be maintained in the desired region for solar energy input systems (which is about 50 to 100 C) by control of the system pressure, for instance by incorporating an inert gas such as nitrogen in the system. Increasing the system pressure by the addition of an inert gas such as nitrogen raises the temperature required to desorb a given proportion of the refrigerant from the adsorbent. This is particularly desirable when using refrigerants which have low boiling points.
The controlling means for producing a continuous alternating operational cycle may comprise valves and shutters operated by electrical, electronic, or mechanical methods or by a combination of such methods. The controlling means operate in response to the change in weight of one or both of the adsorp tionlgeneration units as the apparatus is operated. The weight change is preferably detected by use of a force transducer or weight limit switch associated with one or both adsorption/generation units, these being mounted for example on a suitable flexible support. As the cooled adsorption/generation unit adsorbs vapour the nett weight of the cooled adsorption/generation unit increases whilst that of the heated adsorption/generation unit decreases.The change in weight is sensed by the force transducer or by a weight limit switch which is a simple contact mechanism operated by a small motion. The necessary bistable action is introduced by use of a remanence relay or other bistable switching device triggered by the signal from the force transducer or weight limit switch.
The points at which the changeovers in the alternating cycle occur can be pre-set or adjustable to trigger the controlling means at particular weights of one or both of the adsorption/generation units.
The invention is further illustrated with reference to the drawing accompanying the provisional specification which is a flow diagram. The refrigeration system comprises two adsorption/generation units (1) and (2) which are connectable by valves (3) and (4) respectively to the inlet of condenser (5). The outlet of condenser (5) comprises an expansion valve (6) which is connected to the evaporator cooler (7). The evaporator/cooler (7) is connectable by valve (8) to adsorption/ generation unit (1) or by valve (9) to the adsorption/generation unit (2). The adsorption/generation units comprise means (not shown) by which they can be heated utilising solar radiation. The refrigeration system also comprises heat removal means for removing heat from the condenser and alternately from the adsorption/generation units (1) and (2).The heat removal means comprise cooling water pipes (10) through which cooling water is pumped by pump (11) to cool the condenser (5) and one or other of the absorption/ generation units (1) and (2) as determined by valves (12) and (13). The heat is removed from the cooling system by a radiator (14).
The refrigeration system also comprises controlling means (not shown) for operating the valves (3), (4), (8), (9), (12), (13) and the heating means to produce the required operational cycle. The controlling means operate in response to the change in weight occurring in the units (1) and (2). Force transducers (not shown) placed under units (1) and (2) detect the weight change.
In operation adsorption/generation unit (1) is charged with a suitable refrigerant.
Valves (3), (9) and (13) are opened by the controlling means while valves (4), (8) and (12) are closed so that the condenser (5) and adsorption/generation unit (2) are cooled by the cooling system. Solar heat is allowed to fall on adsorption/generation unit (1) raising its temperature and causing the refrigerant vapour to desorb. The refrigerant vapour passes to the condenser (5) in which it is condensed. The liquid refrigerant is allowed to expand through the expansion valve (6) into the evaporator/cooler (7) where it evaporates thus lowering the temperature of the evaporator/cooler. The refrigerant vapour then passes through valve 9 and is adsorbed in adsorption/generation unit (2) which is being cooled by the cooling water flow in pipes (10).When adsorption/generation unit (1) becomes depleted of the refrigerant the controlling means closes valves (3), (9) and (13) and opens valves (4), (8) and (12), and switches the solar radiation to adsorption/ generation unit (2). The cycle then repeats in the opposite direction.
The radiator (14) may be for instance a heat exchanger supplying heat to a domestic hot water system.
WHAT WE CLAIM IS:
1. A refrigeration system containing a low boiling refrigerant, and having (1) two adsorption/generation units containing a solid adsorbent chargeable with the refrigerant, (2) a condenser the inlet of which is connectable alternately to each adsorption/ generation unit and in which the refrigerant vapour desorbed from an adsorption/generation unit is caused to condense, and associated therewith an expansion valve for discharging the condensed refrigerant, (3) an evaporator/cooler the inlet of which is connected via the expansion valve to the condenser and in which the condensed refrigerant is allowed to evaporate thereby cooling the evaporator/cooler, and the outlet of which is connectable alternately to each adsorption/ generation unit, (4) heating means for alternately heating each adsorption/generation unit, (5) heat removal means for removing heat from the condenser and for alternately cooling each adsorption/generation unit, (6) controlling means for producing a continuous alternating operational cycle in which refrigerant is transferred from one adsorption/generation unit to the other unit and then in the reverse direction, whereby firstly one unit is connected to the condenser and is heated to desorb the refrigerant while the other unit is connected to the evaporator/ cooler and is cooled to adsorb refrigerant vapour, and secondly in a reverse operation the replenished unit is connected to the condenser and is heated while the depleted unit is connected to the evaporator/cooler and is cooled, wherein the controlling means operates in response to the change in weight of one or both of the adsorption/generation units caused by the adsorption/desorption of refrigerant.
2. A refrigeration system as claimed in
Claim 1 wherein the refrigerant is a fluoro hydrocarbon.
3. A refrigeration system as claimed in
Claim 1 or 2 wherein the solid adsorbent is silica gel, carbon, a zeolite or activated alumina.
4. A refrigeration system as claimed in any preceding claim wherein the heating means for alternately heating each adsorption/generation unit comprises a heat source wherein the heat is provided by solar radiation.
5. A refrigeration system as claimed in any preceding claim wherein the heat removal means comprises a system of pipes containing circulating cooling water.
6. A refrigeration system as claimed in any preceding claim wherein heat is removed from the condenser by a system of pipes containing circulating cooling water.
7. A refrigeration system as claimed in any preceding claim wherein an inert gas is contained in the system in addition to the low boiling refrigerant.
8. A refrigeration system as claimed in any preceding claim wherein the weight change is detected by a force transducer or a weight limit switch.
9. A refrigeration system substantially as hereinbefore described with reference to the drawings accompanying the provisional specification.
**WARNING** end of DESC field may overlap start of CLMS **.
Claims (9)
1. A refrigeration system containing a low boiling refrigerant, and having (1) two adsorption/generation units containing a solid adsorbent chargeable with the refrigerant, (2) a condenser the inlet of which is connectable alternately to each adsorption/ generation unit and in which the refrigerant vapour desorbed from an adsorption/generation unit is caused to condense, and associated therewith an expansion valve for discharging the condensed refrigerant, (3) an evaporator/cooler the inlet of which is connected via the expansion valve to the condenser and in which the condensed refrigerant is allowed to evaporate thereby cooling the evaporator/cooler, and the outlet of which is connectable alternately to each adsorption/ generation unit, (4) heating means for alternately heating each adsorption/generation unit, (5) heat removal means for removing heat from the condenser and for alternately cooling each adsorption/generation unit, (6) controlling means for producing a continuous alternating operational cycle in which refrigerant is transferred from one adsorption/generation unit to the other unit and then in the reverse direction, whereby firstly one unit is connected to the condenser and is heated to desorb the refrigerant while the other unit is connected to the evaporator/ cooler and is cooled to adsorb refrigerant vapour, and secondly in a reverse operation the replenished unit is connected to the condenser and is heated while the depleted unit is connected to the evaporator/cooler and is cooled, wherein the controlling means operates in response to the change in weight of one or both of the adsorption/generation units caused by the adsorption/desorption of refrigerant.
2. A refrigeration system as claimed in
Claim 1 wherein the refrigerant is a fluoro hydrocarbon.
3. A refrigeration system as claimed in
Claim 1 or 2 wherein the solid adsorbent is silica gel, carbon, a zeolite or activated alumina.
4. A refrigeration system as claimed in any preceding claim wherein the heating means for alternately heating each adsorption/generation unit comprises a heat source wherein the heat is provided by solar radiation.
5. A refrigeration system as claimed in any preceding claim wherein the heat removal means comprises a system of pipes containing circulating cooling water.
6. A refrigeration system as claimed in any preceding claim wherein heat is removed from the condenser by a system of pipes containing circulating cooling water.
7. A refrigeration system as claimed in any preceding claim wherein an inert gas is contained in the system in addition to the low boiling refrigerant.
8. A refrigeration system as claimed in any preceding claim wherein the weight change is detected by a force transducer or a weight limit switch.
9. A refrigeration system substantially as hereinbefore described with reference to the drawings accompanying the provisional specification.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB20442/76A GB1580432A (en) | 1976-05-18 | 1976-05-18 | Refrigeration apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB20442/76A GB1580432A (en) | 1976-05-18 | 1976-05-18 | Refrigeration apparatus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB1580432A true GB1580432A (en) | 1980-12-03 |
Family
ID=10146024
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB20442/76A Expired GB1580432A (en) | 1976-05-18 | 1976-05-18 | Refrigeration apparatus |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB1580432A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0076079A2 (en) * | 1981-09-25 | 1983-04-06 | The Secretary of State for Defence in Her Britannic Majesty's Government of the United Kingdom of Great Britain and | Improvements in or relating to heat pipes |
| FR2514115A1 (en) * | 1981-10-07 | 1983-04-08 | Philips Nv | TWO-COMPARTMENT REFRIGERATOR |
| FR2619895A1 (en) * | 1987-08-28 | 1989-03-03 | Nishiyodo Air Conditioner | ADSORPTION REFRIGERATION SYSTEM |
| EP0515923A2 (en) * | 1991-05-24 | 1992-12-02 | Polycold Systems International | Combined cryosorption/auto-refrigerating cascade low temperature system |
| WO2010049147A1 (en) * | 2008-10-30 | 2010-05-06 | Airbus Operations Gmbh | Adsorption cooling system and adsorption cooling method for an aircraft |
-
1976
- 1976-05-18 GB GB20442/76A patent/GB1580432A/en not_active Expired
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0076079A2 (en) * | 1981-09-25 | 1983-04-06 | The Secretary of State for Defence in Her Britannic Majesty's Government of the United Kingdom of Great Britain and | Improvements in or relating to heat pipes |
| EP0076079A3 (en) * | 1981-09-25 | 1983-08-10 | The Secretary of State for Defence in Her Britannic Majesty's Government of the United Kingdom of Great Britain and | Improvements in or relating to heat pipes |
| FR2514115A1 (en) * | 1981-10-07 | 1983-04-08 | Philips Nv | TWO-COMPARTMENT REFRIGERATOR |
| FR2619895A1 (en) * | 1987-08-28 | 1989-03-03 | Nishiyodo Air Conditioner | ADSORPTION REFRIGERATION SYSTEM |
| EP0515923A2 (en) * | 1991-05-24 | 1992-12-02 | Polycold Systems International | Combined cryosorption/auto-refrigerating cascade low temperature system |
| EP0515923A3 (en) * | 1991-05-24 | 1993-01-13 | Polycold Systems International | Combined cryosorption/auto-refrigerating cascade low temperature system |
| WO2010049147A1 (en) * | 2008-10-30 | 2010-05-06 | Airbus Operations Gmbh | Adsorption cooling system and adsorption cooling method for an aircraft |
| CN102202969A (en) * | 2008-10-30 | 2011-09-28 | 空中客车作业有限公司 | Adsorption cooling system and adsorption cooling method for an aircraft |
| CN102202969B (en) * | 2008-10-30 | 2013-06-19 | 空中客车作业有限公司 | Adsorption cooling system and adsorption cooling method for an aircraft |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PS | Patent sealed | ||
| PCNP | Patent ceased through non-payment of renewal fee |