EP1775531A1 - Appareil et système de refroidissement et/ou de congélation et de dégivrage - Google Patents

Appareil et système de refroidissement et/ou de congélation et de dégivrage Download PDF

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Publication number
EP1775531A1
EP1775531A1 EP05077340A EP05077340A EP1775531A1 EP 1775531 A1 EP1775531 A1 EP 1775531A1 EP 05077340 A EP05077340 A EP 05077340A EP 05077340 A EP05077340 A EP 05077340A EP 1775531 A1 EP1775531 A1 EP 1775531A1
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EP
European Patent Office
Prior art keywords
cooling medium
circuit
cooling
evaporator
pressure
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.)
Withdrawn
Application number
EP05077340A
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German (de)
English (en)
Inventor
Eppo Viswat
Erik J. Hoogendoorn
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GTI Koudetechnik BV
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GTI Koudetechnik BV
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Publication date
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Priority to EP05077340A priority Critical patent/EP1775531A1/fr
Publication of EP1775531A1 publication Critical patent/EP1775531A1/fr
Withdrawn legal-status Critical Current

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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
    • F25B1/00—Compression machines, plants or systems with non-reversible cycle
    • F25B1/10—Compression machines, plants or systems with non-reversible cycle with multi-stage compression
    • 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
    • F25B47/00—Arrangements for preventing or removing deposits or corrosion, not provided for in another subclass
    • F25B47/02—Defrosting cycles
    • F25B47/022—Defrosting cycles hot gas defrosting
    • 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
    • F25B7/00—Compression machines, plants or systems, with cascade operation, i.e. with two or more circuits, the heat from the condenser of one circuit being absorbed by the evaporator of the next circuit
    • 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
    • F25B2309/00—Gas cycle refrigeration machines
    • F25B2309/06—Compression machines, plants or systems characterised by the refrigerant being carbon dioxide
    • 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
    • F25B2400/07—Details of compressors or related parts
    • F25B2400/075—Details of compressors or related parts with parallel compressors
    • 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
    • F25B2400/13—Economisers

Definitions

  • This invention relates to an apparatus for cooling and/or freezing and defrosting, wherein the apparatus is provided with at least a first pump circulation circuit comprising at least one first evaporator device and at least one first condenser device, a cooling medium present in the first circuit, a first pump device for circulating the cooling medium in the first circuit with the first pump device, wherein the apparatus is arranged such that, in use, the cooling medium flows from the first evaporator device via the first circuit in the gaseous phase to the first condenser device, while the pressure of the cooling medium in the gaseous phase increases to a condensation pressure, so that the cooling medium condenses in the first condenser device at a temperature which is lower than a thawing temperature, for instance lower than 0°C, and the cooling medium flows from the first condenser device via the first circuit in the liquid phase to the first evaporator device, while the pressure decreases to an evaporation pressure, so that the cooling medium evaporates in the first evaporator device, wherein the apparatus
  • the invention further relates to a system provided with a plurality of such cooling apparatuses which are connected in cascade.
  • cooling apparatuses it is typically desired for them to be provided with a thawing device to defrost the first evaporator device.
  • a thawing device to defrost the first evaporator device.
  • the reason is that in use, typically, ice and/or frost will be formed on the first evaporator device, which reduces the efficiency of the apparatus. This ice and/or frost can then be removed by temporarily putting the apparatus out of operation and defrosting the first evaporator device. It may also be necessary to defrost the first evaporator device during use, for instance for releasing a product which has been obtained on the first evaporator device of, for instance, a plate freezer.
  • the first evaporator device may be provided with an electric defrosting element.
  • the apparatus may be provided with an auxiliary circuit in which, for the purpose of defrosting, hot liquid is supplied to the first evaporator device.
  • British patent application 2258298 discloses a system which is provided with a first cooling apparatus and a second cooling apparatus which are connected with each other through a cascade connection.
  • the first cooling apparatus is provided with a cooling medium known per se, such as ammonia
  • the second cooling apparatus is provided with a cooling medium in the form of CO 2 .
  • the evaporator device of the second cooling apparatus will be susceptible to ice deposition because it works at the lowest temperature of the system.
  • this apparatus is provided with means to supply heat from the first cooling apparatus to the second cooling apparatus for defrosting the evaporator device of the second cooling apparatus.
  • Such a method of defrosting has as a disadvantage that heat is required for supply to the second system. Further, it is disadvantageous that additional energy is used to dissipate unused defrosting heat. Moreover, it is disadvantageous that additional means are needed to supply the heat of the first cooling apparatus to the second cooling apparatus.
  • WO 02/066908 discloses a cooling apparatus which comprises CO 2 as cooling medium.
  • the cooling apparatus is provided with a unit which requires at least one additional compressor to obtain CO 2 having a sufficiently high temperature and pressure to be able to defrost the evaporator device.
  • the cooling medium is supplied from a distributing system to the additional compressor, while the pressure of the cooling medium being supplied to the additional compressor is equal to the evaporation pressure in the evaporator.
  • an additional compressor is required for defrosting.
  • a disadvantage of this apparatus is that it takes a relatively great deal of energy to increase the pressure of the cooling medium used for defrosting the evaporator from the low evaporation pressure to the high thawing pressure, so that defrosting is not done energy-efficiently.
  • WO 02/101305 also discloses a system in which an additional compressor is included for increasing the pressure and temperature of the cooling medium, which is also in the form of CO 2 here, in order for the cooling medium to be able to defrost the evaporator device.
  • the cooling medium is supplied from the compressor for the cooling system to the additional compressor, while the pressure of the cooling medium being supplied to the additional compressor is equal to the condensation pressure in the condenser.
  • an additional compressor is needed for defrosting.
  • a disadvantage of this apparatus is that a larger part of the apparatus needs to be designed to be resistant to the high condensation pressure than in, for instance, the apparatus from WO 02/066908 . As a result, a larger part of the apparatus needs to be made of stronger and hence more expensive design.
  • the object of the invention is to provide an alternative to the known devices for defrosting and/or to provide a solution to the above-mentioned disadvantages and/or the problem that relatively costly additional measures are needed to defrost the first evaporator device, which additional measures are used only a relatively small part of the time.
  • the apparatus according to the invention is characterized in that the apparatus is arranged such that the cooling medium is supplied from the first circuit to the second pump device, while a pressure of the cooling medium that is supplied to the second pump device is lower than the condensation pressure in the first condenser device and is higher than the evaporation pressure in the first evaporator device.
  • the cooling medium that is used for defrosting the first evaporator device in the second mode - and to that end is supplied to the thawing device by the second pump device - to be obtained from a location in the apparatus where an intermediate pressure prevails that is lower than the condensation pressure in the first condenser device and is higher than the evaporation pressure in the first evaporator device.
  • This provides the advantage that defrosting the evaporator is done more energy-efficiently than when the cooling medium is supplied to the second pump device with the low evaporation pressure, while the part of the apparatus in which the cooling medium is supplied from the first circuit to the second pump device needs to be resistant only to the intermediate pressure and not to the higher condensation pressure.
  • the apparatus is furthermore provided with a first economizer device which is included in the first circuit downstream of the first condenser device and upstream of the first evaporator device, wherein the cooling medium flows from the first condenser device via the first and second circuit to the first economizer device, while the pressure decreases and at least a part of the cooling medium evaporates in the first economizer device, the cooling medium flows from the first economizer device via the first circuit in the liquid phase to the first evaporator device and the cooling medium flows from the first economizer device via the second circuit in the gaseous phase to the second pump device, the apparatus being further provided with at least one switching element which is included in the second circuit downstream of the first economizer device, the switching element being arranged for, in the first mode, supplying the cooling medium to the first condenser device with a pressure which is equal to the condensation pressure in the first condenser device, and, in the second mode, supplying, at least a part of, the cooling medium to the
  • first economizer device and the second pump device in the first mode have as a function to improve the efficiency of the apparatus in a manner known per se, and that the first economizer device and the second pump device in the second mode have as a function to provide the cooling medium for defrosting the first evaporator device.
  • the first economizer device and the second pump device here have a double function. This provides the advantage that the first economizer device and the second pump device can be used both during defrosting and during cooling and/or freezing.
  • the higher temperature of the cooling medium is then chosen such as to be higher than the thawing temperature of the first evaporator device, for instance higher than 0°C, for causing ice and/or frost to melt.
  • the first evaporator device can be defrosted fast and efficiently.
  • the condensation temperature can for instance be below 0°C in that a condensation pressure of the cooling medium has been chosen low (for instance to ensure a good efficiency, for instance with CO 2 as cooling medium), or through other causes (for instance separation of cooling medium circuits).
  • the first pump device is provided with a first pump which is included in the first circuit downstream of the first evaporator device and upstream of the first condenser device.
  • the second pump device is provided with a second pump which is included in the second circuit downstream of the first economizer device and upstream of the first thawing device and/or the first condenser device.
  • the first circuit and the second circuit are each provided with their own pump. The second pump can then be used to defrost the first evaporator device (in the second mode) and can then also work in cooperation with the first economizer device to improve the efficiency of the apparatus (in the first mode).
  • the apparatus may be further characterized in that the apparatus is further provided with at least a third pump circulation circuit at least comprising the first condenser device and a second economizer device, the second economizer device being included in the first circuit downstream of the first condenser device and upstream of the first evaporator device, for circulating the cooling medium in the third circuit using a third pump device, the apparatus being arranged such that the pressure of the cooling medium in the second economizer device is higher than in the first evaporator device and the cooling medium flows from the second economizer device via the third circuit in the gaseous phase to the first condenser device, while the pressure increases, so that the cooling medium condenses in the first condenser device.
  • a third pump circulation circuit at least comprising the first condenser device and a second economizer device
  • the second economizer device being included in the first circuit downstream of the first condenser device and upstream of the first evaporator device, for circulating the cooling medium in the third
  • the second economizer device is included in the first circuit between the first economizer device and first evaporator device, while the pressure of the cooling medium in the second economizer device is between the pressure of the cooling medium in the first economizer device and the pressure of the cooling medium in the first evaporator device.
  • the pressure of the cooling medium in the first economizer device is at a relatively high level with respect to the pressure in the first evaporator device, so that the cooling medium that flows from the first economizer device into the second circuit can be used well, in the second mode, for defrosting the first evaporator device.
  • the invention further relates to a system provided with a first cooling apparatus according to the invention which in a manner known per se is connected in cascade with one or more other cooling apparatuses.
  • These other cooling apparatuses can also be a cooling apparatus according to the invention, but can also consist of a cooling apparatus known per se.
  • reference numeral 1 designates a cooling apparatus for cooling or freezing.
  • a space 2 is cooled.
  • the apparatus 1 is used for cooling objects, appliances, gases, fluids, foods, etc.
  • the apparatus 1 is provided with at least a first pump circulation circuit 4, the lines of which are in bold-type in Fig. 1.
  • the first pump circulation circuit comprises at least one first evaporator 6.1 of a first evaporator device 7.1 and at least one first condenser 8 of a first condenser device 9.
  • the lines in Fig. 1 can for instance be formed by pipes providing fluid connections between the first evaporator 6.1 and the first condenser 8.
  • the apparatus 1 is further provided with at least a second pump circulation circuit 10, comprising the first condenser 8 and a first economizer 12 of a first economizer device 13.
  • the economizer device 13 is for instance designed as an open economizer device 13 as shown in Fig. 7a.
  • the first economizer 12 is included not only in the second pump circulation circuit 10 but also in the first pump circulation circuit 4.
  • the economizer 12 is situated downstream of the first condenser 8 and upstream of the first evaporator 6.1.
  • the direction of flow of a cooling medium 14 included in the first and second circuits is indicated by arrows.
  • the second pump circulation circuit 10, too, is provided with pipes providing fluid connections between the first condenser 8 and the economizer 12.
  • the first pump circulation circuit 4 is thus provided with the fluid communication segments 16, 18, 20 and 24.
  • the second pump circulation circuit 10 is provided with the fluid communication segment 16, the fluid communication segment 26 and, in this example, a part of the fluid communication segment 24 because the fluid communication segment 26 terminates upstream of the first condenser 8, at a point 36, in the fluid communication segment 24.
  • the fluid communication segment 26 could also have terminated directly in the condenser 8.
  • the economizer device 13 is further provided with a first regulator 28 for the dosed supply of the cooling medium from the condenser 8 to the economizer 12.
  • the evaporator device 7.1 is provided with a second regulator 30 for the dosed supply of the medium from the economizer 12 to the first evaporator 6.1.
  • the first and the second regulator 28, 30 can for instance comprise a high-pressure float or a controllable valve.
  • the first evaporator device 7.1 in this example is further provided with a third regulator 31 which can close and clear the fluid communication segment 20.
  • the first regulator 28 is included in a part of the first and second pump circulation circuits 4, 10 that extends between the first condenser 8 and the economizer 12, that is, in the fluid communication segment 16.
  • the second regulator 30 is included in a part of the first pump circulation circuit 4 that extends from the economizer 12 to the first evaporator 6.1.
  • the apparatus 1 is further provided with a pump system 32 provided with a first pump device 34.
  • the first pump device 34 is provided with a first pump which is situated in the first pump circulation circuit 4 downstream of the first evaporator 6.1 and upstream of the first condenser 8 and also upstream of the point 36 where the second circuit 10, downstream of the economizer 12, terminates in the first circuit 4.
  • the apparatus is provided with a second pump device 38 provided with a second pump which is included in the second circuit 10 downstream of the economizer 12 and upstream of the first condenser 8, more specifically in the section of the second circuit 10 that is not shared with the first circuit 4, that is, upstream of the point 36.
  • the broken lines in Fig. 1 represent pipes 39 which provide return possibilities from the first evaporator 6.1 to for instance the economizer device 13 and/or the condenser device 9.
  • a return line from the first evaporator 6.1 is further provided with a fourth regulator 33.
  • the apparatus 1 is further provided with a control unit 40 which generates control signals C for controlling the pump device 32 and in this example also the first, second, third and fourth regulators 28, 30, 31, 33.
  • the apparatus 1 as described up to this point works as follows.
  • the condenser 8 comprises the cooling medium 14 in inter alia condensed form and under a high pressure which has been generated by the pump 34 and the pump 38.
  • the high pressure is for instance 27 bar.
  • This situation corresponds to the condition of point A of Fig. 8.
  • the cooling medium in liquid form is released in a dosed manner.
  • the pressure has therefore decreased to a value of, for instance, about 14 bar.
  • This pressure decrease is indicated with a single arrow in Fig. 8.
  • the cooling medium is in the condition B of Fig. 8.
  • the pressure is then about 14 bar and the temperature is then approximately -30 °C.
  • a portion of the cooling medium 14 will become gaseous as a result of the pressure decrease.
  • the enthalpy of the cooling medium will increase, which is indicated in Fig. 8 with a double arrow.
  • the pressure of the cooling medium remains approximately 14 bar and the temperature approximately -30 °C.
  • the gaseous portion of the medium is then in point H of the diagram of Fig. 8. This transition is indicated with the double arrow.
  • the liquid portion of the medium will likewise obtain a temperature of approximately -30 °C, so that the enthalpy decreases and the liquid portion of the medium enters the condition C of Fig. 8. This transition is indicated with triple arrows.
  • the liquid portion of the medium is supplied via the regulator 30 in a dosed manner to the first evaporator 6.1.
  • a pressure drop across the regulator 30 will occur, which means that the pressure of the medium in the liquid phase downstream of the regulator 30 will decrease to, for instance, approximately 10 bar.
  • this is indicated by the condition in position D in the diagram.
  • This transition is indicated with triple arrows.
  • the liquid medium will thereupon proceed to evaporate at the pressure of approximately 10 bar.
  • the enthalpy of the medium increases, which is clarified in Fig. 8 in that the cooling medium passes from the condition indicated by D to the condition indicated in the diagram by point E.
  • the energy for the evaporation is drawn from the space 2.
  • the cooling medium in this example has approximately a temperature of -40 °C, so that the extraction of heat from the space 2 and hence the cooling of the space 2 can take place well.
  • the cooling medium in the gaseous phase is drawn in by the first pump device 34 and in the gaseous phase supplied to the first pump device 34 via the regulator 31, which is open to that end.
  • the pressure of the cooling medium 14 is increased strongly.
  • the cooling medium will pass from the condition in point E to point F. This transition is indicated with triple arrows again.
  • the temperature of the cooling medium will decrease and the cooling medium then enters a condition indicated in Fig. 8 by point G.
  • the cooling medium is still in the gaseous phase but is about to condense.
  • the cooling medium will eventually proceed to condense, so that still more heat is imparted to the space 44.
  • the cooling medium goes from point G to point A in the diagram of Fig. 8. Between point G and point A, the transition from the gaseous to the liquid phase occurs at a temperature of approximately -10 °C. This transition is also indicated with triple arrows.
  • the condensation pressure has therefore been chosen such that, in the first mode, the condensation temperature is below the thawing temperature, more particularly below 0 °C. It will be clear, however, that the condensation temperature can also be chosen to be higher than the thawing temperature. From point A where the cooling medium is completely in the liquid phase, the cooling medium can proceed to traverse the first circuit 4 again.
  • a portion of the cooling medium that is in the gaseous phase that is, the cooling medium being in the condition of point H in the diagram of Fig. 8, is supplied to the second pump device 38.
  • the cooling medium that is supplied to the second pump device 38 has a pressure which is higher than the pressure of the cooling medium in the first evaporator 6.1 and lower than the pressure of the cooling medium in the condenser 8. With the aid of the second pump device 38, the pressure of the cooling medium in the gaseous phase is raised. The condition of the cooling medium then passes from point H to point I in the diagram of Fig. 8. This transition is indicated with a double arrow.
  • the cooling medium Downstream of the second pump device 38, the cooling medium has a pressure of approximately 27 bar and a condensation temperature of approximately -10 °C, i.e. below the thawing temperature. From point I, the cooling medium that is delivered by the second pump device 38, together with the cooling medium that is delivered by the first pump device 34, is supplied to the condenser 8, after which the cooling medium passes from the condition I to the condition G and from the condition G to the condition A as discussed above for the cooling medium that was delivered by the first pump device 34. This transition is indicated with a double arrow.
  • the cooling capacity increases by a value corresponding to arrow 46.
  • an amount of energy must be supplied that corresponds to arrow 47. Since a greater amount of cooling medium is associated with the arrow 46 than with the arrow 47, the absolute amount of required energy associated with the arrow 47 is lower than the absolute amount of energy associated with the arrow 46.
  • the specific cooling capacity is therefore increased by the use of the economizer device. The apparatus described up to this point is known per se.
  • the apparatus 1 is further provided with at least one fluid connection 50, closable in a first mode and to be cleared in a second mode, which finds its origin in the second circuit 10 between the economizer 12 and the first condenser 8 at a position where the pressure of the cooling medium in a gaseous phase is greater than the pressure of the cooling medium in the gaseous phase in the economizer 12. In this example, this position is downstream of the second pump device 38.
  • the apparatus 1 is provided with a (controllable) valve 52.
  • the fluid connection 50 in this example terminates directly in the first evaporator 6.1. As will be indicated hereinafter, the fluid connection 50 can be utilized for defrosting the first evaporator 6.1.
  • the control device 40 will control the valve 52, such that the cooling medium that is delivered by the second pump device 38 is supplied, wholly or partly, to the first fluid connection 50.
  • the valve 52 has for instance such properties that a portion of the cooling medium is supplied to the fluid connection 50, to a first thawing device 15.1 for defrosting the first evaporator device 7.1, and a portion of the cooling medium is supplied to the condenser 8. All this, of course, under the control of the control unit 40.
  • the regulators 30 and 31 may then be closed for preventing a flow of the cooling medium through the first circuit 4 through the first evaporator 6.1, so that the first evaporator is not cooled during defrosting.
  • the first thawing device 15.1 can for instance comprise a thawing device known per se, such as a condenser and/or a pipe which is in thermal contact with the first evaporator 6.1 for imparting heat to the first evaporator 6.1.
  • the first economizer device 13 Since the cooling medium that is delivered by the second pump device 38 comes from the first economizer device 13, the first economizer device 13 will furnish, at least a part of, the energy (heat) that is needed for defrosting the first evaporator 6.1.
  • the cooling medium In the fluid connection 50 the cooling medium is in condition K. In condition K the cooling medium is superheated and then has a temperature of approximately 20 °C.
  • the pressure of the cooling medium that is supplied to the fluid connection 50 has therefore been chosen such that, in the second mode, the condensation temperature of the cooling medium is above the thawing temperature, more particularly above 0 °C.
  • this cooling medium which proceeds to flow through and/or along the first evaporator 6.1 will start to defrost the first evaporator 6.1. It is also possible that during defrosting the first circuit 4 continues to function as discussed above.
  • the fluid connection 50 is omitted and replaced with a fluid connection 50' which terminates in the first evaporator device 7.1.
  • the fluid connection 50' finds its origin in the second circuit 10 downstream of the first economizer device 13 and upstream of the first condenser device 9.
  • the fluid connection 50' is provided with a pump 37 and optionally a valve 52'. If it is desired to defrost the first evaporator device 7.1, the control device 40 will control the pump 37 and/or the valve 52', such that pump 37 supplies cooling medium via the first fluid connection 50' to the first evaporator device 7.1.
  • valve 52 the fluid connection between valve 52 and point 36 is omitted.
  • the second pump circulation circuit 10 cannot be used in the first mode, but can only be used to defrost in the second mode. In that case, the apparatus is not provided with a second pump circulation circuit that works to increase the efficiency of the apparatus.
  • the apparatus 1 functions for cooling the space 2, this will be called the first mode of the cooling apparatus.
  • the fluid connection 50 is then not utilized because the valve 52 is so controlled that the cooling medium from the second pump device 38 flows exclusively to the first condenser 8.
  • the cooling medium from the second pump device 38 flows, at least partly, to the first evaporator 6.1 via the fluid connection 50 (or fluid connection 50').
  • it holds in the second mode that with the pump system 32, in this case with the second pump device 38, and/or with the valve 52, at the above-mentioned position of the valve which in this example is formed by the valve 52 in the second circuit 10, a higher pressure (and thus possibly a higher temperature) of the cooling medium is realized than in the first mode.
  • the control unit 40 then controls for instance the second pump device 38 and/or valve 52, such that the pressure of the cooling medium runs up much further.
  • the cooling medium obtains a pressure of approximately 40 bar in this example.
  • the cooling medium then passes from condition H to condition K in the diagram of Fig. 8.
  • the cooling medium then has a relatively high temperature of approximately 40 °C.
  • the pressure of the cooling medium has been chosen such that, in the second mode, the condensation temperature of the cooling medium downstream of the second pump device 38 is above the thawing temperature, more particularly, above 0 °C. This transition is indicated with quadruple arrows.
  • the cooling medium is supplied under this high pressure to the first thawing device of the first evaporator device 7.1.
  • the temperature of the cooling medium will decrease as a result of the ice and/or frost present on the outside of the first evaporator 6.1.
  • the pressure remains approximately 40 bar.
  • the cooling medium then passes from condition K to condition L in the diagram of Fig. 8. This transition is indicated with quadruple arrows.
  • the cooling medium having a temperature which is approximately equal to 5 °C will start to condense. During this condensation, still more heat is imparted to the first evaporator 6.1, so that the ice and/or the frost on the first evaporator 6.1 will melt.
  • the cooling medium passes from condition L to condition M, the temperature remaining approximately constant.
  • the pressure will decrease.
  • a regulating element such as a throttle element, in this example regulator 33
  • the cooling medium will end up in condition N.3 in Fig. 8.
  • the cooling medium is supplied by the first pump device 34 to the condenser 8, after which the cooling medium condenses completely and ends up in condition A again. After this, the whole cycle can repeat itself.
  • the cooling medium from the regulator 33 is supplied via the return line 39 to an inlet I 1 of the economizer device 13.
  • the cooling medium will then end up in condition N.2 in Fig. 8. If the cooling medium from the regulator 33 is supplied via the return line 39 to an inlet I 1 of the condenser device 9, the cooling medium will end up in condition N.1 in Fig. 8.
  • the fluid connection 50 can then extend to each of the first evaporator devices 7.i.
  • the arrangement it is then possible for the arrangement to be set up such that with the aid of the fluid connection 50 for defrosting the evaporator device 7.1 the fluid having the high temperature is supplied first to the evaporator device 7.1, next to the evaporator device 7.2, then to the evaporator device 7.3, etc., and finally to the evaporator device 7.n.
  • the first evaporator devices 7.i can be defrosted one by one.
  • valves 54.1-54.n may be arranged in fluid connection 50. These valves can then be controlled by the control device 40 again. It will be clear that, also, a first plurality of evaporator devices can be operated in the first mode, whilst a second plurality of evaporator devices are operated in the second mode.
  • pump devices 34 and 38 this may be understood to mean any device for the purpose of increasing the pressure.
  • the first pump device 34 and the second pump device 38 can for instance each be designed as a compressor or more compressors.
  • FIG. 3 presently a further elaboration of the apparatus according to Fig. 1 or Fig. 2 is discussed. Parts corresponding to Figs. 1 and 2 are provided with the same reference numerals. For simplicity, the return lines 39 are not represented.
  • the apparatus has been provided not with just one economizer device 13 but also with a second economizer device 13' which in this example is in fluid communication with a third pump device 38'.
  • the second economizer device 13' and the third pump device 18' are part of a third circuit 10'.
  • the second economizer device 13' in this example is provided with a second economizer 12', which is for instance designed as an open economizer.
  • the cooling medium in the liquid phase from the economizer 12 is supplied via the regulator 28' across which a pressure drop occurs, to the second economizer 12'.
  • a portion of the cooling medium will evaporate and in the gaseous form be supplied to the third pump device 38'. Another portion will not evaporate and will be supplied in liquid form via a regulator 30 across which a pressure drop occurs, to the first evaporator 6.1.
  • the point R is located to the left of point D, so that the specific cooling capacity increases.
  • the third pump device 38' ensures that the cooling medium goes to point S to be subsequently supplied in this condition to the first condenser 8.
  • the fluid connection 50 still springs downstream of the second pump device 38 for obtaining hot gas which in the second mode can be supplied to the first evaporator 6.1 for defrosting.
  • this hot gas can also be obtained downstream of the third pump device 38'.
  • the apparatus may be further provided with more economizer devices, for instance third economizer device 13" comprising for instance a third economizer which is in fluid communication with a fourth pump device 38" for further enlarging the cooling capacity.
  • third economizer device 13" and the fourth pump device 38" are then part of a fourth circuit 10".
  • the cooling medium coming from each of the pump devices 38, 38', 38" can be used according to the invention for defrosting the first evaporator 6.i.
  • the apparatus according to Fig. 1 may further be connected in cascade with other cooling apparatuses and thus form a system according to the invention as shown in Fig. 4.
  • reference numeral 1 denotes an apparatus according to the invention.
  • the cooling medium here comprises for instance CO 2 .
  • the first condenser device 9 is then, for instance through a first heat exchanger 80, at least partly coupled with an evaporator device 7.1' of a cooling apparatus 1' known per se.
  • the cooling apparatus 1' known per se comprises in this example a condenser device 9', an evaporator device 7.1' and a pump system 32'.
  • the cooling apparatus 1' can for instance comprise NH 3 as cooling medium.
  • the cooling apparatus 1' may, if desired, also be designed as a cooling apparatus 1 according to the invention and thus be provided with means for defrosting the evaporator device 7.1' entirely analogously to the manner as discussed with reference to Fig. 1.
  • the system according to Fig. 4 may also be provided with a cooling apparatus 1" instead of the cooling apparatus 1'.
  • the cooling apparatus 1" may again be provided with a condenser device 9", an evaporator device 7.1" and a pump system 32". This involves a cooling apparatus known per se again, or, for instance, a cooling apparatus which, as described above, is provided with means to defrost the first evaporator device 7.1".
  • the system is then further provided with a second heat exchanger 82 which connects the first evaporator device 7.1 of the cooling apparatus 1, at least partly, in a heat conductive manner with the condenser device 9" of the cooling apparatus 1".
  • a second heat exchanger 82 which connects the first evaporator device 7.1 of the cooling apparatus 1, at least partly, in a heat conductive manner with the condenser device 9" of the cooling apparatus 1".
  • the cooling apparatus 1" can for instance be provided with a cooling medium such as CO 2 or NH 3 but also other cooling media are conceivable. This holds for each of the above-outlined cooling apparatuses 1, 1' and 1".
  • the system is provided with more than one cooling apparatus which are connected in cascade.
  • the cooling apparatus 1 may then, for instance, be coupled with cooling apparatus 1' and the cooling apparatus 1" as shown in Fig. 4.
  • Different sequential orders of coupling whereby, for instance, the cooling apparatus 1 and the cooling apparatus 1' are interchanged, or the cooling apparatus 1 and the cooling apparatus 1" are interchanged, also belong to the invention.
  • the system may further be provided with more than one cooling apparatus which are coupled in cascade. It is also conceivable that each of the cooling apparatuses is provided with a plurality of evaporator devices.
  • each cooling apparatus is further provided with a plurality of condenser devices that are connected in parallel, all this entirely analogously to the above discussion regarding the first evaporator devices 7.1 - 7.n. It is also conceivable that the second circuit 10, downstream of the regulator 52, terminates directly in the first condenser device 9 (and any other condenser devices). Also, a plurality of condenser devices 9 may be connected in series. This also holds for the evaporator devices 7.i.
  • the evaporator devices can be designed in various ways.
  • the inlets of the evaporator devices are indicated by I 1 and I 2 and the outlets of the evaporator devices by O 1 and O 2 .
  • the inlet I 1 and the outlet O 1 then form the connections for the evaporators 6.i.
  • the inlet I 2 and the outlet O 2 then form the connections for the thawing devices 15.i.
  • a possible general embodiment of an evaporator is shown in Fig. 5a.
  • the evaporator device 7.1 is composed of an evaporator unit 70 and a throttle element 72 which are connected in series.
  • the throttle element 72 is then an example of the regulator 30.
  • the evaporator device 7.1 may be additionally provided with a second throttle element 73.
  • the throttle element 73 is then an example of the regulator 31.
  • FIG. 5b A specific embodiment of an evaporator device 7.1 is shown in Fig. 5b.
  • the evaporator device 7.1 is provided with a vat 74, a pump 76, a number of heat exchangers 78 and a throttle element 72.
  • FIG. 5c Another possible embodiment of an evaporator device 7.1 is shown in Fig. 5c.
  • the evaporator of Fig. 5c is provided with throttle elements 72 and heat exchangers 78.
  • the condenser devices 9 of the embodiments outlined above may be designed in various ways.
  • an inlet of a condenser is in each case indicated with I 1
  • an outlet of a condenser is indicated with O 1 .
  • the condenser device 9 is provided with a vat 74 which is provided with a heat exchanger 75.
  • the operation of such a condenser device is known per se.
  • the condenser device according to Fig. 6b which is likewise provided with a vat 74 and a heat exchanger 75.
  • Fig. 6c again an alternative embodiment is given of a condenser device which is provided with a single heat exchanger 75 and is not provided with a storage vessel.
  • economizer devices 13 In Figs. 7a and 7b, a number of examples are given of economizer devices 13. An inlet is in each case indicated with I 1 and the outlets are respectively indicated by O 1 and O 2 .
  • Fig. 7a shows an economizer device 13 according to the principle of an open system.
  • This economizer device 13 is provided with a throttle element 72 and a vat 74 which are connected in series.
  • the throttle element 72 is then an example of the regulator 28.
  • a economizer device 13 according to a closed system is shown.
  • This economizer device is provided with a throttle element 72 and a heat exchanger.
  • the two branches 75 of the heat exchanger can be in thermal contact, while the branch with outlet O 2 functions as evaporator and in the branch with outlet O 1 the cooling medium is cooled down.
  • the various types of evaporator devices, economizer devices and condenser devices can be used interchangeably in the various outlined systems according to the invention.
  • a closed economizer device is used, as for instance shown in Fig. 7b, the operation of the apparatus from point A in Fig. 8 is as follows.
  • a first part of the cooling medium is supplied via a regulator (for instance throttle element 72 in Fig. 7b) to a first part of a heat exchanger of the economizer device.
  • a pressure drop occurs. Downstream of the regulator, the pressure has therefore fallen to a value of for instance approximately 14 bar.
  • This pressure decrease is indicated in Fig. 8 with a single arrow.
  • the cooling medium is in the condition B of Fig. 8. The pressure is then approximately 14 bar and the temperature has then decreased to approximately -30 °C.
  • a second part of the cooling medium is supplied in liquid form into the economizer device 13 via a second part of the heat exchanger.
  • the temperature of the cooling medium will then decrease as a result of the lower temperature in the first part of the heat exchanger.
  • the second part of the cooling medium will, in the second part of the heat exchanger, go from point A to point T in Fig. 8.
  • the first part of the cooling medium will evaporate in the first part of the heat exchanger and pass from condition B to condition H in Fig. 8, after which the first part of the cooling medium will further traverse the second circuit 10 as described in relation to Fig. 1.
  • the second part of the cooling medium is supplied in a dosed manner via the regulator 30 to the first evaporator 6.1.
  • a pressure drop across the regulator 30 will occur, which means that the pressure of the medium in the liquid phase downstream of the regulator 30 will decrease to for instance approximately 10 bar.
  • the second part of the cooling medium will pass from condition T to condition W in Fig. 8.
  • the liquid cooling medium will then proceed to evaporate at the pressure of approximately 10 bar.
  • the enthalpy of the medium increases, which is clarified in Fig. 8 in that the cooling medium passes from the condition indicated by W to the condition indicated in the diagram by point E, after which the second part of the cooling medium will further traverse the first circuit 4 as described in relation to Fig. 1.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Defrosting Systems (AREA)
EP05077340A 2005-10-12 2005-10-12 Appareil et système de refroidissement et/ou de congélation et de dégivrage Withdrawn EP1775531A1 (fr)

Priority Applications (1)

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EP05077340A EP1775531A1 (fr) 2005-10-12 2005-10-12 Appareil et système de refroidissement et/ou de congélation et de dégivrage

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EP05077340A EP1775531A1 (fr) 2005-10-12 2005-10-12 Appareil et système de refroidissement et/ou de congélation et de dégivrage

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008142714A1 (fr) * 2007-05-22 2008-11-27 Angelantoni Industrie Spa Dispositif de réfrigération et procédé pour faire circuler un fluide de réfrigération associé à celui-ci
EP2005079A1 (fr) * 2006-03-27 2008-12-24 Carrier Corporation Système de réfrigération avec circuits d'économiseur étagés en parallèle et compresseur principal à un ou deux étages
EP2280234A3 (fr) * 2009-07-20 2012-10-10 Systemes LMP Inc Système de dégivrage et procédé pour système de réfrigération R-744 sous-critique en cascade
CN110762586A (zh) * 2019-10-12 2020-02-07 青岛海信日立空调系统有限公司 一种复叠压缩热泵系统
CN113310235A (zh) * 2021-06-17 2021-08-27 青岛理工大学 一种高低冷凝自动切换的复叠式变频热泵系统及运行方法

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS54146048A (en) * 1978-05-08 1979-11-14 Mitsubishi Electric Corp Double-step compression type freezer
US4324106A (en) * 1980-10-03 1982-04-13 H. A. Phillips & Co. Refrigeration system
WO2002101305A1 (fr) * 2001-06-13 2002-12-19 York Refrigeration Aps Degivrage a l'aide d'un gaz chaud de co2 dans les systemes de refrigeration en cascade
EP1422487A2 (fr) * 2002-11-21 2004-05-26 York Refrigeration APS Dégivrage par gaz chaud pour installations frigorifiques
US20050138936A1 (en) * 2002-07-08 2005-06-30 Dube Serge High-speed defrost refrigeration system

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS54146048A (en) * 1978-05-08 1979-11-14 Mitsubishi Electric Corp Double-step compression type freezer
US4324106A (en) * 1980-10-03 1982-04-13 H. A. Phillips & Co. Refrigeration system
WO2002101305A1 (fr) * 2001-06-13 2002-12-19 York Refrigeration Aps Degivrage a l'aide d'un gaz chaud de co2 dans les systemes de refrigeration en cascade
US20050138936A1 (en) * 2002-07-08 2005-06-30 Dube Serge High-speed defrost refrigeration system
EP1422487A2 (fr) * 2002-11-21 2004-05-26 York Refrigeration APS Dégivrage par gaz chaud pour installations frigorifiques

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 004, no. 009 (M - 089) 23 January 1980 (1980-01-23) *

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2005079A1 (fr) * 2006-03-27 2008-12-24 Carrier Corporation Système de réfrigération avec circuits d'économiseur étagés en parallèle et compresseur principal à un ou deux étages
EP2005079A4 (fr) * 2006-03-27 2011-11-30 Carrier Corp Système de réfrigération avec circuits d'économiseur étagés en parallèle et compresseur principal à un ou deux étages
WO2008142714A1 (fr) * 2007-05-22 2008-11-27 Angelantoni Industrie Spa Dispositif de réfrigération et procédé pour faire circuler un fluide de réfrigération associé à celui-ci
JP2010528250A (ja) * 2007-05-22 2010-08-19 アンジェラントーニ インダストリエ エスピーエー 冷却デバイス、および冷却流体を循環させるための方法
AU2007353615B2 (en) * 2007-05-22 2012-04-12 Angelantoni Industrie Spa Refrigerating device and method for circulating a refrigerating fluid associated with it
AU2007353615B9 (en) * 2007-05-22 2012-04-19 Angelantoni Industrie Spa Refrigerating device and method for circulating a refrigerating fluid associated with it
US8505317B2 (en) 2007-05-22 2013-08-13 Angelantoni Life Science SRI Refrigerating device and method for circulating a refrigerating fluid associated with it
EP2280234A3 (fr) * 2009-07-20 2012-10-10 Systemes LMP Inc Système de dégivrage et procédé pour système de réfrigération R-744 sous-critique en cascade
CN110762586A (zh) * 2019-10-12 2020-02-07 青岛海信日立空调系统有限公司 一种复叠压缩热泵系统
CN113310235A (zh) * 2021-06-17 2021-08-27 青岛理工大学 一种高低冷凝自动切换的复叠式变频热泵系统及运行方法
CN113310235B (zh) * 2021-06-17 2021-12-31 青岛理工大学 一种高低冷凝自动切换的复叠式变频热泵系统及运行方法

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