US20160245575A1 - Co2 refrigeration system for ice-playing surfaces - Google Patents

Co2 refrigeration system for ice-playing surfaces Download PDF

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US20160245575A1
US20160245575A1 US15/091,082 US201615091082A US2016245575A1 US 20160245575 A1 US20160245575 A1 US 20160245575A1 US 201615091082 A US201615091082 A US 201615091082A US 2016245575 A1 US2016245575 A1 US 2016245575A1
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refrigerant
heat
refrigeration
evaporation
ice
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US15/091,082
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Serge Dube
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TOROMONT INDUSTRIES Ltd
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TOROMONT INDUSTRIES Ltd
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Priority to CA2724255A priority patent/CA2724255C/en
Priority to CA2724255 priority
Priority to US13/247,562 priority patent/US20120073319A1/en
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25CPRODUCING, WORKING OR HANDLING ICE
    • F25C3/00Processes or apparatus specially adapted for producing ice or snow for winter sports or similar recreational purposes, e.g. for sporting installations; Producing artificial snow
    • F25C3/02Processes or apparatus specially adapted for producing ice or snow for winter sports or similar recreational purposes, e.g. for sporting installations; Producing artificial snow for ice rinks
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT-PUMP SYSTEMS
    • F25B25/00Machines, plant, or systems, using a combination of modes of operation covered by two or more of the groups F25B1/00 - F25B23/00
    • F25B25/005Machines, plant, or systems, using a combination of modes of operation covered by two or more of the groups F25B1/00 - F25B23/00 using primary and secondary systems
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT-PUMP SYSTEMS
    • F25B31/00Compressor arrangements
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT-PUMP SYSTEMS
    • F25B9/00Compression machines, plant, or systems, in which the refrigerant is air or other gas of low boiling point
    • F25B9/002Compression machines, plant, or systems, in which the refrigerant is air or other gas of low boiling point characterised by the refrigerant
    • F25B9/008Compression machines, plant, or systems, in which the refrigerant is air or other gas of low boiling point characterised by the refrigerant the refrigerant being carbon dioxide
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT-PUMP SYSTEMS
    • F25B2309/00Gas cycle refrigeration machines
    • F25B2309/06Compression machines, plant or systems characterised by the refrigerant being carbon dioxide
    • F25B2309/061Compression machines, plant or systems characterised by the refrigerant being carbon dioxide with cycle highest pressure above the supercritical pressure
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT-PUMP SYSTEMS
    • F25B29/00Combined heating and refrigeration systems, e.g. operating alternately or simultaneously
    • F25B29/003Combined heating and refrigeration systems, e.g. operating alternately or simultaneously of the compression type system
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT-PUMP SYSTEMS
    • F25B30/00Heat pumps
    • F25B30/06Heat pumps characterised by the source of low potential heat

Abstract

A CO2 refrigeration system comprises a condensation reservoir. CO2 refrigerant is accumulated in the reservoir. The CO2 refrigerant circulates between supra-compression and evaporation loops. The supracompression loop comprises a compression stage for compression CO2 refrigerant to a supracompression state, a cooling stage in which CO2 refrigerant releases heat, and a pressure-regulating unit in a line extending from the cooling stage to the condensation reservoir. The pressure-regulating unit maintains a pressure differential between the cooling stage and the condensation reservoir. The evaporation loop comprises an evaporation stage in which CO2 refrigerant from the condensation reservoir absorbs heat in a heat exchanger. The heat exchanger is connected to an ice-playing surface refrigeration circuit. A second refrigerant cycles in the ice-playing surface refrigeration circuit. The CO2 refrigerant absorbs heat from the second refrigerant in the heat exchanger. A CO2 condensation exchanger is also provided.

Description

    CROSS-REFERENCE TO RELATED APPLICATION(S)
  • The present application is a divisional of U.S. patent application Ser. No. 13/247,562 filed on Sep. 28, 2011 which claims the benefit of U.S. Provisional Patent Applications No. 61/387,087, filed on Sep. 28, 2010, and No. 61/415,982, filed on Nov. 22, 2010 and which claims priority to Canadian Patent Application No. 2,724,255, filed on Dec. 17, 2010, now Canadian Patent No. 2,724,255, issued on Sep. 13, 2011. All of the above-mentioned applications are incorporated herein by reference in their entirety.
  • FIELD OF THE APPLICATION
  • The present application relates to refrigeration systems used in industrial refrigeration applications, such as rinks, curling centers and arenas, to refrigerate an ice-skating or ice-playing surface, and more particularly to such refrigeration systems using CO2 refrigerant.
  • BACKGROUND OF THE ART
  • With the growing concern for global warming, the use of chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) as refrigerant has been identified as having a negative impact on the environment. These chemicals have non-negligible ozone-depletion potential and/or global-warming potential.
  • As alternatives to CFCs and HCFCs, ammonia, hydrocarbons and CO2 are used as refrigerants. Although ammonia and hydrocarbons have negligible ozone-depletion potential and global-warming potential as does CO2, these refrigerants are highly flammable and therefore represent a risk to local safety. On the other hand, CO2 is environmentally benign and locally safe.
  • Ice-playing surfaces typically have large-scale heat exchangers disposed under the ice surface to refrigerate the ice surface. Considering the specific use of such refrigeration systems, and thus the requirement for a refrigerant at a precise range of temperature, brine is currently used in such refrigeration systems. The brine circulates in a closed circuit and is in a heat-exchange relation with a refrigeration circuit. However, these refrigeration circuits often use refrigerants that are harmful to the environment.
  • SUMMARY OF THE APPLICATION
  • It is therefore an aim of the present disclosure to provide a CO2 refrigeration system for ice surfaces, that addresses issues associated with the prior art.
  • Therefore, in accordance with the present application, there is provided a CO2 refrigeration system comprising a CO2 condensation reservoir in which CO2 refrigerant is accumulated and circulates between a supracompression loop and an evaporation loop; the supracompression loop comprising a compression stage in which CO2 refrigerant from at least the CO2 condensation reservoir is compressed to at least a supracompression state, a cooling stage in which the CO2 refrigerant from the compression stage releases heat, and a pressure-regulating unit in a line extending from the cooling stage to the CO2 condensation reservoir to maintain a pressure differential therebetween; and the evaporation loop comprising an evaporation stage in which the CO2 refrigerant from at least the CO2 condensation reservoir absorbs heat in a heat exchanger, the heat exchanger being connected to an ice-playing surface refrigeration circuit in which cycles a second refrigerant, such that the CO2 refrigerant absorbs heat from the second refrigerant in the heat exchanger.
  • Further in accordance with the present application, there is provided a CO2 refrigeration system comprising a CO2 condensation exchanger for heat exchange between a supracompression loop of CO2 refrigerant and an evaporation loop of CO2 refrigerant; the supracompression loop comprising a compression stage in which CO2 refrigerant having absorbed heat in the condensation exchanger is compressed to at least a supracompression state, a cooling stage in which the CO2 refrigerant from the compression stage releases heat, and a pressure-regulating unit in a line extending from the cooling stage to the condensation exchanger to maintain a pressure differential therebetween; and the evaporation loop comprising a condensation reservoir in which CO2 refrigerant having released heat in the condensation exchanger is accumulated in a liquid state, and an evaporation stage in which the CO2 refrigerant from the condensation reservoir absorbs heat to cool an ice-playing surface, to then return to one of the condensation reservoir and the condensation exchanger.
  • Still further in accordance with the present application, there is provided a CO2 refrigeration system comprising a CO2 condensation reservoir in which CO2 refrigerant is accumulated and circulates between a supracompression loop and an evaporation loop; the supracompression loop comprising a compression stage in which CO2 refrigerant from at least the CO2 condensation reservoir is compressed to at least a supracompression state, a cooling stage in which the CO2 refrigerant from the compression stage releases heat, and a pressure-regulating unit in a line extending from the cooling stage to the CO2 condensation reservoir to maintain a pressure differential therebetween; the evaporation loop comprising an evaporation stage of pipes under an ice-playing surface in which circulates the CO2 refrigerant to absorb heat to cool an ice-playing surface, to then return to the CO2 condensation reservoir; and a geothermal well loop in heat-exchange relation with the CO2 refrigerant, the geothermal well loop having a geothermal heat exchanger for heat exchange between the CO2 refrigerant of one of the evaporation loop and the compression loop and another refrigerant absorbing heat from the CO2 refrigerant, the geothermal well loop extending to a geothermal well in which the other refrigerant releases heat geothermally.
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • FIG. 1 is a block diagram of a CO2 refrigeration system for skating surfaces in accordance with a first embodiment;
  • FIG. 2 is a block diagram of a CO2 refrigeration system for skating surfaces in accordance with a second embodiment;
  • FIG. 3 is a block diagram of a CO2 refrigeration system with a geothermal well in accordance with a third embodiment;
  • FIG. 4 is a block diagram of a CO2 refrigeration system with a geothermal well in accordance with a fourth embodiment; and
  • FIG. 5 is a schematic view of a modulated pressure-relief system for use with the CO2 refrigeration systems of the previous figures.
  • DESCRIPTION OF THE PREFERRED EMBODIMENTS
  • Referring to FIG. 1, a CO2 refrigeration system in accordance with an embodiment is illustrated at 1. The CO2 refrigeration system 1 has a CO2 refrigeration circuit comprising a CO2 condensation reservoir 12. The condensation reservoir 12 accumulates CO2 refrigerant in a liquid and gaseous state, and may be in a heat-exchange relation with a closed condensation circuit that absorbs heat from the CO2 refrigerant, with examples given hereinafter.
  • Line 14 directs CO2 refrigerant from the condensation reservoir 12 to an evaporation stage via pump(s) 15 or expansion valve(s). As is shown in FIG. 1, the CO2 refrigerant is supplied in a liquid state by the condensation reservoir 12 into line 14. The pump 15 ensures a suitable flow of liquid CO2 refrigerant to the evaporation exchanger 16. In some instances, expansion valve(s) 15 may be used to control the pressure of the CO2 refrigerant, which is then fed to the evaporation exchanger 16. Any appropriate means may be used to put the CO2 refrigerant in suitable condition, such as heat exchangers to vaporize the refrigerant.
  • The evaporation exchanger 16 features the heat exchange between the CO2 refrigerant and the refrigerant of the ice-playing surface. The ice-playing surface refrigerant circulating in the ice-playing surface is typically brine, but may be other types of fluid, such as alcohol-based fluid (e.g., glycol) or the like. In one embodiment, the CO2 circulates in pipes upon which fins are provided. The pipes of the evaporator exchanger 16 are typically positioned in a bath of the ice-playing surface refrigerant. In another embodiment, the refrigeration system 1 is retrofitted to an existing ice-playing surface refrigeration circuit 17. It is pointed out that the expansion valve(s) 15 may be part of a refrigeration pack in the mechanical room, as opposed to being at the evaporation exchanger 16.
  • The CO2 refrigerant exiting the evaporation stage 16 is returned to the condensation reservoir 12 via line 18. Alternatively, the CO2 refrigerant may be directed to the inlet of compressors of the transcritical circuit or loop, via line 19. In such a case, it may be required to provide some form of protection in line 19 to vaporize the CO2 refrigerant fed to the inlet of the compressors, such as an evaporator, a heat exchanger or source of heat, valves, among numerous possibilities.
  • The transcritical circuit or loop (i.e., supracompression circuit) is provided to compress the CO2 refrigerant exiting from the condensation reservoir 12 to a transcritical state, for heating purposes, or supracompressed state. In both compression states, the CO2 refrigerant is pressurized with a view to maintaining the condensation reservoir 12 at a high enough pressure to allow vaporized CO2 refrigerant to be circulated in the evaporation stage 16, as opposed to liquid CO2 refrigerant. In one embodiment, the pressure is high enough for the CO2 refrigerant to circulate to the evaporation exchanger 16 via the action of the pump 15.
  • A line 30 (using valve 30A) relates the condensation reservoir 12 to a heat exchanger 31 and subsequently to a supracompression stage 32. The heat exchanger 31 or any other appropriate means may be provided to vaporize the CO2 refrigerant fed to the supracompression stage 32 (e.g., feed from a top of the condensation reservoir 12, multiple reservoirs in specific arrangement, etc). The supracompression stage 32 features one or more compressors (e.g., Bock™, Dorin™), that compress the CO2 refrigerant to a supra-compressed or transcritical state.
  • In the supracompressed or transcritical state, the CO2 refrigerant is used to heat a secondary refrigerant via heat-reclaim exchanger 34, or may be used directly in a heating unit, with a fluid such as air blown thereon to heat parts of the building related to the ice-playing surface. In the heat-reclaim exchanger 34, the CO2 refrigerant is in a heat-exchange relation with the secondary refrigerant circulating in the secondary refrigerant circuit 35, or with a fluid blown on the heat exchanger 34. In the event that a secondary refrigerant is used, the secondary refrigerant is preferably an environmentally sound refrigerant, such as water or glycol, that is used as a heat-transfer fluid. Because of the supracompressed or transcritical state of the CO2 refrigerant, the secondary refrigerant circulating in the circuit 35 reaches a high temperature. Accordingly, due to the high temperature of the secondary refrigerant, lines of smaller diameter may be used for the secondary refrigerant circuit 35. It is pointed out that the secondary refrigerant circuit 35 may be the largest of the circuits of the refrigeration system 1 in terms of quantity of refrigerant. Therefore, the compression of the CO2 refrigerant into a transcritical state by the transcritical circuit allows the lines of the secondary refrigerant circuit 35 to be reduced in terms of diameter. It is pointed out that heat-reclaim exchanger 34 may include individual heating units used to produce heat locally. Such heating units 35 are typically a coil and fan assembly. The control of the amount of refrigerant sent to each heating unit 35 is described hereinafter.
  • A gas-cooling stage 36 is provided in the transcritical circuit. The gas-cooling stage 36 absorbs excess heat from the CO2 refrigerant in the transcritical state, with a view to re-injecting the CO2 refrigerant into the condensation reservoir 12. Although it is illustrated in a parallel relation with the heat-reclaim exchanger 34, the gas-cooling stage 36 may be in series therewith, or in any other suitable arrangement. Although not shown, appropriate valves are provided so as to control the amount of CO2 refrigerant directed to the gas-cooling stage 36, in view of the heat demand from the heat-reclaim exchanger 34.
  • In warmer climates in which the demand for heat is smaller, the CO2 refrigerant is compressed to a supracompressed state, namely at a high enough pressure to allow the expansion of the CO2 refrigerant at the exit of the condensation reservoir 12, so as to reduce the amount of CO2 refrigerant circulating in the refrigeration circuit. A by-pass line is provided to illustrate that the heat-reclaim exchanger 34 and the gas-cooling stage 36 may be optional for warmer climates.
  • The gas-cooling stage 36 may feature a fan blowing a gas refrigerant on coils. The speed of the fan may be controlled as a function of the heat demand of the heat-reclaim exchanger 34. For an increased speed of the fan, there results an increase in the temperature differential at opposite ends of the gas-cooling stage 36.
  • Lines 37 and 38 return the CO2 refrigerant to the condensation reservoir 12, and thus to the refrigeration circuit. The line 37 may feed the heat exchanger 31 such that the CO2 refrigerant exiting the stages 34 and 36 releases heat to the CO2 refrigerant fed to the supracompression stage 32, for the CO2 refrigerant fed to the supracompression stage 32 to be in a gaseous state.
  • In the case of transcritical compression, a CO2 transcritical pressure-regulating valve 39 is provided to maintain appropriate pressures at the stages 34 and 36, and in the condensation reservoir 12. The CO2 transcritical pressure-regulating valve 39 is for instance a Danfoss™ valve. Any other suitable pressure-control, pressure-regulating, pressure-reducing device may be used as an alternative to the valve 39, such as any type of valve or loop.
  • The condensation circuit and the supracompression circuit allow the condensation reservoir 12 to store refrigerant at a relatively medium pressure. The pump 15 then ensures the circulation of the CO2 refrigerant in the evaporation exchanger 16. In the embodiment featuring expansion valve 15, as CO2 refrigerant is vaporized downstream of the expansion valve 15, the amount of CO2 refrigerant in the refrigeration circuit is reduced, especially if the expansion valve 15 is in the refrigeration pack.
  • It is considered to operate the supracompression circuit (i.e., supra-compression 32) with higher operating pressure. CO2 refrigerant has a suitable efficiency at a higher pressure. More specifically, more heat can be extracted when the pressure is higher.
  • Referring now to FIG. 2, there is illustrated a CO2 refrigeration system 2 for ice-playing surfaces. The CO2 refrigeration system 2 is similar to the CO2 refrigeration system 1 of FIG. 1, whereby like elements will bear like reference numerals. One difference between refrigeration systems 1 and 2 is that the refrigeration system 2 features two closed circuits of refrigerant in addition to the ice-playing surface refrigeration circuit 17. More specifically, the CO2 refrigeration circuit 2 of FIG. 2 has a condensation exchanger 50 by which the refrigerant circulating in the main refrigeration circuit 40 (i.e., CO2 or other refrigerants, if suitable) is in a heat-exchange relation with CO2 refrigerant circulating in the transcritical/supracompression circuit. Accordingly, in the condensation exchanger 50, the CO2 refrigerant circulating in the supracompression/transcritical circuit is used to absorb heat from the refrigerant circulating in the main refrigeration circuit 40. In an embodiment, both refrigerants are CO2.
  • Referring to FIG. 3, there is illustrated a CO2 refrigeration system 3 similar to the CO2 refrigeration systems 1 and 2, whereby like elements and components will bear like reference numerals. The valve 30A in line 30 may be an expansion valve, evaporative pressure-regulating valve, control valve or the like so as to ensure that the compressors 32 are fed with vaporized CO2 refrigerant. The refrigeration system 3 has one or more heating units 35 at the outlet of the supracompression stage 32, in any given arrangement with the exchanger 34 and gas-cooling stage 36. The heating units 35 are typical direct-heating units, having coils in which CO2 refrigerant circulates and upon which air is blown for heating purposes.
  • According to an embodiment, there are a plurality of the heating units 35. In another embodiment, the heating units 35 are in a parallel relation, and they may or may not be fed with CO2 refrigerant as a function of the heating requirements. Moreover, the speed of the fans of the heating units 35 may also be controlled for this purpose. A valve or valves 35A are used to control the amount of CO2 refrigerant sent to each of the heating units 35 and/or to heat-reclaim exchanger 34. For instance, if two of the heating units 35 cover two different zones having different heating requirements, the valves 35A and fans of each unit may be adjusted to meet the local heating requirements. One configuration is to have thermostats for the various zones to adjust the amount of refrigerant sent to the heating units 35 via the adjustment of the valves 35A.
  • A reservoir 55 may be provided between lines 37 and 38 to receive CO2 refrigerant, and ensure it is fed in suitable condition to the condensation exchanger 50. For instance, the line 38 may tap into a bottom of the reservoir 55 to direct liquid CO2 refrigerant to the condensation exchanger 50. A valve 56 (e.g., expansion valve) may be provided to ensure that the CO2 refrigerant is in a suitable state to absorb heat from the CO2 refrigerant. In an embodiment, valve 56 is used as pressure differential valve instead of valve 39 (not required in such a case to reduce the pressure), with the supracompression pressure maintained upstream of valve 56. With this configuration, the pressure of the CO2 refrigerant in the main refrigeration circuit 40 may be kept lower, or other refrigerants may be used in the main refrigeration circuit 40.
  • Still referring to FIG. 3, a heat exchanger 60 is illustrated as extending from the condensation reservoir 12 and in fluid communication therewith so as to receive a feed of CO2 refrigerant. The heat exchanger 60 is in fluid communication with a geothermal well 61 by a geothermal circuit. A refrigerant (e.g., glycol, or any appropriate refrigerant such as alcohol-based refrigerants or the like) circulates in the geothermal circuit, so as to absorb heat from the CO2 refrigerant in the heat exchanger 60 and release the heat in the well 61. Appropriate pumps 62 and/or 63 or flow controlling means may be used to ensure that there is a suitable flow of refrigerant to the heat exchanger 60. The pumps 62 and 63 are variably controlled.
  • In FIG. 3, although the refrigeration system 3 is shown with an evaporation exchanger 16 and ice-rink cooling, the refrigeration system 3 may be used for any appropriate type of refrigeration, with or without an evaporation exchanger 16. Moreover, the refrigeration system 3 may be operated without a geothermal well in appropriate conditions.
  • Referring to FIG. 4, a CO2 refrigeration system 4 similar to the CO2 refrigeration systems 1, 2 and 3 is illustrated, whereby like elements and components will bear like reference numerals. The refrigeration system 4 features a geothermal well loop, but does not have a condensation exchanger 50 as does the refrigeration system 3. The CO2 refrigeration system 4 may be used to refrigerate a skating rink or the like. For simplicity purposes, the evaporation stage is generally shown as 17. In the embodiment in which the CO2 refrigerant is sent directly in the pipes of the ice-playing surface as part of the evaporation stage 17, the pump(s) 15 is well suited to induce a suitable flow of liquid CO2 refrigerant into the pipes of the ice-playing surface.
  • The refrigeration systems 1-3 may be used with existing ice-playing surface piping, or as part of new ice-rink refrigeration systems. The evaporation exchanger 16 is modified to receive CO2 refrigerant. It may be required that the coils be modified in view of the specifications of the CO2 refrigerant versus the brine or other refrigerant used in the ice-playing surface piping. The CO2 refrigeration systems 1-3 advantageously use the existing hardware related to the ice-playing surface refrigeration. It is pointed out that the CO2 refrigeration systems 1-3 need not be used only in a retrofit configuration.
  • Referring to FIG. 5, there is illustrated a modulated pressure-relief system which may be used with any one of the CO2 refrigeration systems 1-4 of the previous figures, if appropriate. The modulated pressure-relief system has a line 70 that is in fluid communication with the evaporators of the refrigeration system. A pair of valves 71 and 72 are in a parallel arrangement with the line 70, and are part of exhaust lines opened to the atmosphere, for exhausting CO2 refrigerant. Valve 71 is a modulating valve, automatically operable from a set point pressure. The modulating valve 71 therefore gradually opens upon the pressure in the line reaching the set point pressure. Any other gradually-opening type of valve may be used as valve 71. For instance, valve 71 may be operated by a controller (e.g., central processing unit of the CO2 refrigeration systems), or may be a mechanical valve with an appropriate controlled-opening mechanism.
  • Valve 72 is a pressure-relief valve. The pressure-relief valve 72 has its own set point pressure, which is higher than the set point pressure of the modulating valve 71. The pressure-relief valve 72 opens when the set point pressure is reached. Accordingly, if the pressure is high in the evaporators, but not at the set point of relief, the pressure increase in the evaporators 70 will be modulated to reduce the pressure increase. The opening of valve 72 in a relief condition may be controlled so as to be a slow release to limit the release of refrigerant to the atmosphere. Valve 72 may be any appropriate type of relief valve, such as a mechanical valve, or a valve controlled by the controller of the CO2 refrigeration system.
  • The CO2 refrigeration systems described above for FIGS. 1-4 are generally separated into a supracompression loop and an evaporation loop. The supracompression loop comprises the supracompression stage, while the evaporation loop comprises the evaporation stage. The loops may be separated from one another by the condensation exchanger 50 (FIGS. 2 and 3), in which case the CO2 refrigerant does not circulate between loops. In FIGS. 1 and 4, the loops are interrelated by the condensation reservoir 12, in which case the CO2 refrigerant circulates between loops.
  • The CO2 refrigeration systems described above for FIGS. 1-4 are used for ice-playing surfaces, which may include ice-skating surfaces of arenas or of outdoor applications, skating rinks (e.g., speed skating), the playing surface of curling centers, or any other application in which a relatively large-scale refrigerated surface is used. Moreover, although the word “ice” is used (and thus water), it is understood that the medium used for the surface may be any appropriate fluid reaching a solid state.

Claims (11)

1. A CO2 refrigeration system for an ice-playing surface, comprising:
a CO2 refrigerant circuit in which CO2 refrigerant circulates and having at least
a compression stage in which CO2 refrigerant is compressed and an evaporation stage in which heat is absorbed from an ice-playing surface,
a plurality of CO2 compressors in the compression stage for compressing CO2 refrigerant subcritically and transcritically,
a gas cooling stage comprising at least a plurality of heat-reclaim units reclaiming heat from the CO2 refrigerant compressed in the compression stage,
a pressure-regulating device downstream of the gas cooling stage, the pressure-regulating device operable to control a pressure of the CO2 refrigerant in the gas cooling stage as a function of a heat demand of the plurality of heat-reclaim units,
a reservoir downstream of the pressure-regulating device for receiving CO2 refrigerant in a liquid state, and
an evaporation side of at least one heat exchanger downstream of the reservoir for the CO2 refrigerant to absorb heat; and
a second refrigerant circuit in which a second refrigerant circulates and having at least
a condensation side of the at least one heat exchanger for the second refrigerant to release heat to the CO2 refrigerant in the evaporation side, and
piping in a floor of an ice-playing surface in which the second refrigerant refrigerates the ice-playing surface.
2. The CO2 refrigeration system according to claim 1, wherein the gas cooling stage further comprises at least one of a gas-cooling unit and a heat-reclaim exchanger.
3. The CO2 refrigeration system according to claim 1, comprising valves provided in relation to the plurality of heat-reclaim units to individually control a feed of CO2 refrigerant directed to each said heat-reclaim unit.
4. The CO2 refrigeration system according to claim 1, wherein a fan of each said heat-reclaim unit is actuated as a function of a temperature demand.
5. The CO2 refrigeration system according to claim 1, further comprising at least one pump in the second refrigerant circuit to induce a flow of the second refrigerant therein.
6. The CO2 refrigeration system according to claim 1, further comprising a line extending from the evaporation side of the at least one heat exchanger to the compression stage, to direct the CO2 refrigerant exiting the evaporation side thereat.
7. The CO2 refrigeration system according to claim 1, wherein a portion of the heat-reclaim units are in a parallel arrangement.
8. The CO2 refrigeration system according to claim 1, wherein a portion of the heat-reclaim units are in a series arrangement.
9. The CO2 refrigeration system according to claim 1, further comprising at least one expansion valve upstream of said piping to vaporize the second refrigerant fed to the piping.
10. The CO2 refrigeration system according to claim 1, further comprising at least one pump downstream of the reservoir to direct liquid CO2 refrigerant to the evaporation side of the at least one heat exchanger.
11. The CO2 refrigeration system according to claim 1, wherein the second refrigerant is one of glycol and brine.
US15/091,082 2010-09-28 2016-04-05 Co2 refrigeration system for ice-playing surfaces Abandoned US20160245575A1 (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
US38708710P true 2010-09-28 2010-09-28
US41598210P true 2010-11-22 2010-11-22
CA2724255A CA2724255C (en) 2010-09-28 2010-12-17 Co2 refrigeration system for ice-playing surfaces
CA2724255 2010-12-17
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10663201B2 (en) 2018-10-23 2020-05-26 Hill Phoenix, Inc. CO2 refrigeration system with supercritical subcooling control

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DK177329B1 (en) 2011-06-16 2013-01-14 Advansor As Refrigeration system
BR112014027770A2 (en) * 2012-05-11 2017-06-27 Hill Phoenix Inc co2 cooling system with integrated air conditioning module
US9194615B2 (en) 2013-04-05 2015-11-24 Marc-Andre Lesmerises CO2 cooling system and method for operating same
US9822993B2 (en) * 2013-12-03 2017-11-21 Systemes Lmp Inc. Transcritical R744 refrigeration system for skating rinks with total condensation and without flash-gas bypass
CA2928553A1 (en) * 2015-04-29 2016-10-29 Marc-Andre Lesmerises Co2 cooling system and method for operating same

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5826433A (en) * 1997-03-25 1998-10-27 Dube; Serge Refrigeration system with heat reclaim and efficiency control modulating valve
US20150354882A1 (en) * 2008-10-23 2015-12-10 Serge Dube Co2 refrigeration system

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3721388C1 (en) * 1987-06-29 1988-12-08 Sueddeutsche Kuehler Behr Device for air conditioning the interior of passenger cars
US5319945A (en) * 1992-06-29 1994-06-14 American Standard Inc. Method and apparatus for non-atmospheric venting of evaporator over-pressure in a refrigeration system
US5575159A (en) * 1995-06-02 1996-11-19 Dittell; Edward W. Heat energy transfer system
US6796139B2 (en) * 2003-02-27 2004-09-28 Layne Christensen Company Method and apparatus for artificial ground freezing
CN100507402C (en) * 2004-08-09 2009-07-01 卡里尔公司 CO2 refrigeration circuit with sub-cooling of the liquid refrigerant against the receiver flash gas and method for operating the same
CN101060789A (en) * 2004-11-17 2007-10-24 麻省理工学院 Frozen food
JP2008530511A (en) * 2005-02-18 2008-08-07 キャリア コーポレイションCarrier Corporation Refrigeration circuit with improved liquid / vapor receiver

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5826433A (en) * 1997-03-25 1998-10-27 Dube; Serge Refrigeration system with heat reclaim and efficiency control modulating valve
US20150354882A1 (en) * 2008-10-23 2015-12-10 Serge Dube Co2 refrigeration system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10663201B2 (en) 2018-10-23 2020-05-26 Hill Phoenix, Inc. CO2 refrigeration system with supercritical subcooling control

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