CA3028201A1 - Subcritical carbon dioxide dehumidifier - Google Patents
Subcritical carbon dioxide dehumidifier Download PDFInfo
- Publication number
- CA3028201A1 CA3028201A1 CA3028201A CA3028201A CA3028201A1 CA 3028201 A1 CA3028201 A1 CA 3028201A1 CA 3028201 A CA3028201 A CA 3028201A CA 3028201 A CA3028201 A CA 3028201A CA 3028201 A1 CA3028201 A1 CA 3028201A1
- Authority
- CA
- Canada
- Prior art keywords
- carbon dioxide
- dehumidifier
- subcritical carbon
- pressure
- main line
- 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.)
- Pending
Links
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 title claims abstract description 104
- 229910002092 carbon dioxide Inorganic materials 0.000 title claims abstract description 52
- 239000001569 carbon dioxide Substances 0.000 title claims abstract description 52
- 238000005057 refrigeration Methods 0.000 claims description 7
- 239000003507 refrigerant Substances 0.000 abstract description 20
- 239000007788 liquid Substances 0.000 description 11
- 238000007599 discharging Methods 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 1
- 230000003750 conditioning effect Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000001934 delay Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 231100001261 hazardous Toxicity 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 231100000252 nontoxic Toxicity 0.000 description 1
- 230000003000 nontoxic effect Effects 0.000 description 1
- 230000001932 seasonal effect Effects 0.000 description 1
- 230000036967 uncompetitive effect Effects 0.000 description 1
- 238000013022 venting Methods 0.000 description 1
- 238000010792 warming Methods 0.000 description 1
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F3/00—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems
- F24F3/12—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling
- F24F3/14—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling by humidification; by dehumidification
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F1/00—Room units for air-conditioning, e.g. separate or self-contained units or units receiving primary air from a central station
- F24F1/0007—Indoor units, e.g. fan coil units
- F24F1/0083—Indoor units, e.g. fan coil units with dehumidification means
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- 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
- F25B43/00—Arrangements for separating or purifying gases or liquids; Arrangements for vaporising the residuum of liquid refrigerant, e.g. by heat
- F25B43/006—Accumulators
-
- 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
- F25B49/005—Arrangement or mounting of control or safety devices of safety devices
-
- 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
- F25B9/00—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point
- F25B9/002—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point characterised by the refrigerant
- F25B9/008—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point characterised by the refrigerant the refrigerant being carbon dioxide
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F3/00—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems
- F24F3/12—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling
- F24F3/14—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling by humidification; by dehumidification
- F24F2003/144—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling by humidification; by dehumidification by dehumidification only
- F24F2003/1446—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling by humidification; by dehumidification by dehumidification only by condensing
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- 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
- F25B2400/00—General features or devices for refrigeration machines, plants or systems, combined heating and refrigeration systems or heat-pump systems, i.e. not limited to a particular subgroup of F25B
- F25B2400/16—Receivers
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- 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
- F25B2500/00—Problems to be solved
- F25B2500/07—Exceeding a certain pressure value in a refrigeration component or cycle
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- 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
- F25B2600/00—Control issues
- F25B2600/25—Control of valves
- F25B2600/2523—Receiver valves
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- 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
- F25B2600/00—Control issues
- F25B2600/25—Control of valves
- F25B2600/2525—Pressure relief valves
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- 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
- F25B2700/00—Sensing or detecting of parameters; Sensors therefor
- F25B2700/19—Pressures
- F25B2700/193—Pressures of the compressor
- F25B2700/1931—Discharge pressures
-
- 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
- F25B2700/00—Sensing or detecting of parameters; Sensors therefor
- F25B2700/19—Pressures
- F25B2700/195—Pressures of the condenser
-
- 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
- F25B2700/00—Sensing or detecting of parameters; Sensors therefor
- F25B2700/21—Temperatures
- F25B2700/2104—Temperatures of an indoor room or compartment
-
- 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
- F25B2700/00—Sensing or detecting of parameters; Sensors therefor
- F25B2700/21—Temperatures
- F25B2700/2115—Temperatures of a compressor or the drive means therefor
- F25B2700/21152—Temperatures of a compressor or the drive means therefor at the discharge side of the compressor
-
- 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
- F25B2700/00—Sensing or detecting of parameters; Sensors therefor
- F25B2700/21—Temperatures
- F25B2700/2116—Temperatures of a condenser
- F25B2700/21163—Temperatures of a condenser of the refrigerant at the outlet of the condenser
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Combustion & Propulsion (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Analytical Chemistry (AREA)
- Power Engineering (AREA)
- Drying Of Gases (AREA)
Abstract
A subcritical carbon dioxide dehumidifier, having a compressor, a condenser, a receiver, an expansion valve, an evaporator, and an expansion tank and using carbon dioxide as a refrigerant.
Description
Subcritical Carbon Dioxide Dehumidifier Field of the Invention [0001] The present invention relates to dehumidifiers, in particular, to dehumidifiers that use carbon dioxide as a refrigerant.
Background
Background
[0002] The use of carbon dioxide as a refrigerant is well known, however, the fact that the critical point of carbon dioxide is relatively low, particularly compared to many other common refrigerants, creates challenges for its successful application. Carbon dioxide has a critical point of 31.1 C and 1,071 psia, above which it behaves as a supercritical fluid.
Normal ambient temperatures can exceed the critical temperature of carbon dioxide, resulting in high operating pressures within a dehumidifier system.
Normal ambient temperatures can exceed the critical temperature of carbon dioxide, resulting in high operating pressures within a dehumidifier system.
[0003] As a result, dehumidifiers using carbon dioxide as a refrigerant have hereto been designed and built to withstand pressures of up to 1,300 psia. This increases the cost of such units to the point where they are commercially uncompetitive with dehumidifiers that use other refrigerants, such as R-404a or R-407c. However, carbon dioxide has a number of desirable characteristics as a refrigerant. For example, many common refrigerants, such as R-407c, are hazardous if inhaled, whereas carbon dioxide is non-toxic. Carbon dioxide is also a by-product of many industrial processes and, as a result, is readily available at a low cost. Further, refrigerants such as hydrofluorocarbons (HFCs) can have a serious environmental impact, through their high global warming potential (GWP).
[0004] In applications where ambient temperature in the operating environment generally remains below the critical temperature for carbon dioxide, such as in a hockey arena, dehumidifiers that use carbon dioxide as a refrigerant may be designed and built having lower operating pressures. However, during a power outage or when the seasonal ambient temperatures are above .. the critical temperature and pressure within the dehumidifier system can increase above the critical point, the excess pressure created by the supercritical carbon dioxide must be released by discharging a portion of the refrigerant. The system will then require a new charge of refrigerant before it can return to normal operation, which can cause delays and be costly for large dehumidifiers, such as those used in hockey arenas.
Summary of the Invention
Summary of the Invention
[0005] A subcritical carbon dioxide dehumidifier, according to the present invention, has a compressor, a condenser, a receiver, an expansion valve, an evaporator, and an expansion tank and uses carbon dioxide as a refrigerant.
Brief Description of the Drawings
Brief Description of the Drawings
[0006] In order that the invention may be more clearly understood, a preferred embodiment thereof will now be described in detail by way of example, with reference to the accompanying drawings, in which:
[0007] Figure I is a schematic view of a subcritical carbon dioxide dehumidifier, according to the present invention.
[0008] Figure 2 is graph showing the compressor operating envelope for the subcritical carbon dioxide dehumidifier.
Description of the Invention
Description of the Invention
[0009] A subcritical carbon dioxide dehumidifier, according to the present invention, uses .. carbon dioxide as the refrigerant and maintains the system at a subcritical temperature throughout the refrigeration cycle. The dehumidifier is described herein with reference to the example application of a hockey arena, but may be used in any application where the ambient temperature is generally below the critical temperature of carbon dioxide. The dehumidifier has an expansion tank to accommodate an increase in pressure resulting from the carbon dioxide refrigerant temperature increasing above its critical point, such as during a power outage or seasonally. This permits the system to avoid discharging refrigerant to relieve excess pressure and thereby retain a full refrigerant charge when the ambient temperature is in the supercritical range of carbon dioxide.
[0010] As shown schematically in Figure I, the carbon dioxide dehumidifier, referred to herein as the dehumidifier, has a compressor 1, a condenser 2, a receiver 3, an expansion valve 4, an evaporator 5, and an expansion tank 6. The operation of the compressor 1, condenser 2, receiver 3, expansion valve 4, and evaporator 5 in the basic closed circuit refrigeration cycle are well known and, accordingly, are described briefly herein. These parts are located within a housing (not shown), having an air inlet and outlet, which is generally located on the roof of the facility and the air is ducted to and from the dehumidifier. The dehumidifier may also be located directly in the space it is conditioning, such as on a mezzanine of a hockey arena, and the air inlet receives air from the space at one location and the air outlet blows air back into the same space at a different location.
[0011] The basic closed circuit refrigeration cycle of the dehumidifier operates as follows.
Low-pressure low-temperature carbon dioxide gas is drawn into the compressor 1 and is compressed and supplied to the condenser 2 as a high-pressure high-temperature gas. In the condenser 2, the high-pressure high-temperature carbon dioxide gas transfers heat to the air passing over the condenser 2 and condenses to high-pressure high-temperature liquid carbon dioxide. The high-pressure high-temperature liquid carbon dioxide then enters the receiver 3, where it is stored until needed. The high-pressure high-temperature liquid carbon dioxide then flows through the expansion valve 4, which restricts the flow of liquid and lowers the pressure of the liquid. The low-pressure low-temperature liquid carbon dioxide then enters the evaporator 5, typically as an aerosolized mixture of gas and liquid, where it absorbs heat from the air. This causes the liquid carbon dioxide to evaporate as it absorbs heat in the evaporator 5, to result in a low-temperature low-pressure gas that is supplied to the compressor 1 to continue the refrigeration cycle.
Low-pressure low-temperature carbon dioxide gas is drawn into the compressor 1 and is compressed and supplied to the condenser 2 as a high-pressure high-temperature gas. In the condenser 2, the high-pressure high-temperature carbon dioxide gas transfers heat to the air passing over the condenser 2 and condenses to high-pressure high-temperature liquid carbon dioxide. The high-pressure high-temperature liquid carbon dioxide then enters the receiver 3, where it is stored until needed. The high-pressure high-temperature liquid carbon dioxide then flows through the expansion valve 4, which restricts the flow of liquid and lowers the pressure of the liquid. The low-pressure low-temperature liquid carbon dioxide then enters the evaporator 5, typically as an aerosolized mixture of gas and liquid, where it absorbs heat from the air. This causes the liquid carbon dioxide to evaporate as it absorbs heat in the evaporator 5, to result in a low-temperature low-pressure gas that is supplied to the compressor 1 to continue the refrigeration cycle.
[0012] The above refrigeration cycle is carried out in the main line 7 of the dehumidifier, which is defined by the compressor 1, the condenser 2, the receiver 3, the expansion valve 4, the evaporator 5, and the connections therebetween. The main line 7 of the dehumidifier has a high-pressure side 9, between the compressor 1 and the expansion valve 4, and a low-pressure side 10, between the expansion valve 4 and the compressor 1.
[0013] As shown in Figure 1, the expansion tank 6 is on a secondary line 8, which is connected to the main line 7, and together with the main line 7 forms a closed refrigeration circuit. Preferably, the expansion tank 6 connects to the main line 7 in two places, a first connection 11 on the high-pressure side 9, between the evaporator 5 and the compressor 1, and a second connection 12 on the low-pressure side 10, between the condenser 2 and the receiver 3. This permits the first connection 11 to operate as a drain line from the expansion tank 6 to the compressor suction line.
[0014] A control valve 13 on the first connection 11 prevents the flow of high-pressure liquid carbon dioxide into the expansion tank 6 under normal operating conditions.
Preferably, the control valve 13 is a normally open solenoid valve, so that if the control valve 13 is not energized, for any reason, the solenoid valve opens and allows the high pressure gas to expand into the expansion tank 6. The control valve 13 is opened when pressure in the high-pressure side 9 increases beyond a safety threshold value, to permit high-pressure carbon dioxide to flow into the expansion tank 6 and thereby relieve pressure from the main line 7.
Preferably, the control valve 13 is a normally open solenoid valve, so that if the control valve 13 is not energized, for any reason, the solenoid valve opens and allows the high pressure gas to expand into the expansion tank 6. The control valve 13 is opened when pressure in the high-pressure side 9 increases beyond a safety threshold value, to permit high-pressure carbon dioxide to flow into the expansion tank 6 and thereby relieve pressure from the main line 7.
[0015] Preferably, the main line 7 is provided with one or more pressure relief valves 14, which operate as a failsafe to release pressure in the event the control valve 13 of expansion tank 6 fails and pressure builds up in the main line 7. The expansion tank 6 may also have a pressure relief valve 14, in case the pressure in the expansion tank 6 exceeds acceptable levels. Because carbon dioxide is used as the refrigerant, there is minimal safety hazard in venting excess refrigerant through the pressure relief valves 14. Nonetheless, preferably, the pressure relief valves 14 discharge excess refrigerant to an outside area.
[0016] A filter 15 may be included on the main line 7 between the receiver 3 and the expansion valve 4 to maintain the clean and moisture free operation of the dehumidifier.
A view port 16 may also be provided on the main line 7 between the receiver 3 and the expansion valve 4 to permit observation of the liquid column passing between the receiver 3 and the expansion valve 4.
A view port 16 may also be provided on the main line 7 between the receiver 3 and the expansion valve 4 to permit observation of the liquid column passing between the receiver 3 and the expansion valve 4.
[0017] A control system monitors temperatures and pressures throughout the dehumidifier and controls the operation of the dehumidifier. As shown in Figure 1, the control system monitors the temperature and pressure in the main line 7 between the compressor 1 and the condenser 2 and between the receiver 3 and the expansion valve 4. The control system may also monitor the humidity and temperature of the space and control the operation of the dehumidifier based on set humidity and/or temperature thresholds.
[0018] In a typical hockey arena, the ambient temperature is roughly 6 C. Accordingly, the air passing over the condenser 2 cools the high-pressure carbon dioxide vapour into a high-pressure liquid and at the same time increases the temperature of the air to approximately 10 C. The air then passes through the evaporator 5, where the temperature is below the dew point of the air, thereby dehumidifying the air and cooling it to approximately 7 C. The net increase in temperature of the air passing through the dehumidifier is desirable for applications such as hockey arenas, because it reduces the amount of heating otherwise required for the space.
[0019] At normal operating conditions, the high side pressure is between 450 psi and 650 psi, while the low side pressure is between 300 psi and 400 psi. High side pressure refers to the pressure of the carbon dioxide in the high-pressure side 9 of the main line 7.
Similarly, low side pressure refers to the pressure of the carbon dioxide in the low-pressure side 10 of the main line 7.
Similarly, low side pressure refers to the pressure of the carbon dioxide in the low-pressure side 10 of the main line 7.
[0020] The present invention has been described and illustrated with reference to an exemplary embodiment, however, it will be understood by those skilled in the art that various changed may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention as set out herein. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed herein.
Claims (12)
1. A subcritical carbon dioxide dehumidifier, comprising a compressor, a condenser, a receiver, an expansion valve, an evaporator, and an expansion tank and connections therebetween forming a closed refrigeration circuit.
2. The subcritical carbon dioxide dehumidifier of claim 1, wherein the compressor, condenser, receiver, expansion valve, evaporator, and the connections therebetween define a main line.
3. The subcritical carbon dioxide dehumidifier of claim 2, wherein the main line has a high-pressure side between the compressor and the expansion valve and a low-pressure side between the expansion valve and the compressor.
4. The subcritical carbon dioxide dehumidifier of claim 3, having a secondary line that connects to the main line by a first connection and a second connection, and wherein the expansion tank is located on the secondary line.
5. The subcritical carbon dioxide dehumidifier of claim 4, wherein the first connection connects to the high-pressure side of the main line and the second connection connects to the low-pressure side of the main line.
6. The subcritical carbon dioxide dehumidifier of claim 5, wherein the first connection connects between the evaporator and the compressor.
7. The subcritical carbon dioxide dehumidifier of claim 6, wherein the second connection connects between the condenser and the receiver.
8. The subcritical carbon dioxide dehumidifier of claim 7, having a control valve on the first connection that selectively prevents the flow of carbon dioxide into the expansion tank.
9. The subcritical carbon dioxide dehumidifier of claim 8, wherein the control valve is a normally open solenoid valve.
10. The subcritical carbon dioxide dehumidifier of claim 9, having one or more pressure relief valves on the main line.
11. The subcritical carbon dioxide dehumidifier of claim 10, having a pressure relief valve on the expansion tank.
12. The subcritical carbon dioxide dehumidifier of claim 11, having a filter on the main line, located between the receiver and the expansion valve.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US201762611138P | 2017-12-28 | 2017-12-28 | |
US62/611,138 | 2017-12-28 |
Publications (1)
Publication Number | Publication Date |
---|---|
CA3028201A1 true CA3028201A1 (en) | 2019-06-28 |
Family
ID=67057452
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA3028201A Pending CA3028201A1 (en) | 2017-12-28 | 2018-12-21 | Subcritical carbon dioxide dehumidifier |
Country Status (2)
Country | Link |
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US (1) | US20190203991A1 (en) |
CA (1) | CA3028201A1 (en) |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP4959873B2 (en) * | 2001-01-11 | 2012-06-27 | 株式会社前川製作所 | Supercritical continuous processing method and apparatus for liquid material and supercritical continuous processing system combined with refrigeration cycle |
-
2018
- 2018-12-20 US US16/226,924 patent/US20190203991A1/en not_active Abandoned
- 2018-12-21 CA CA3028201A patent/CA3028201A1/en active Pending
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Publication number | Publication date |
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US20190203991A1 (en) | 2019-07-04 |
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EEER | Examination request |
Effective date: 20221207 |
|
EEER | Examination request |
Effective date: 20221207 |
|
EEER | Examination request |
Effective date: 20221207 |