EP1422487A2 - Dégivrage par gaz chaud pour installations frigorifiques - Google Patents

Dégivrage par gaz chaud pour installations frigorifiques Download PDF

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Publication number
EP1422487A2
EP1422487A2 EP03026471A EP03026471A EP1422487A2 EP 1422487 A2 EP1422487 A2 EP 1422487A2 EP 03026471 A EP03026471 A EP 03026471A EP 03026471 A EP03026471 A EP 03026471A EP 1422487 A2 EP1422487 A2 EP 1422487A2
Authority
EP
European Patent Office
Prior art keywords
compressor
evaporator
defrost
compressor section
defrosting
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Withdrawn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
EP03026471A
Other languages
German (de)
English (en)
Other versions
EP1422487A3 (fr
Inventor
Per Skaerbaek Nielsen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Johnson Controls Denmark ApS
Original Assignee
Johnson Controls Denmark ApS
York Refrigeration ApS
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Johnson Controls Denmark ApS, York Refrigeration ApS filed Critical Johnson Controls Denmark ApS
Publication of EP1422487A2 publication Critical patent/EP1422487A2/fr
Publication of EP1422487A3 publication Critical patent/EP1422487A3/fr
Withdrawn legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • 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
    • 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
    • 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
    • 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
    • F25B2400/22—Refrigeration systems for supermarkets

Definitions

  • a refrigeration plant comprising at least one compressor, which compressor is delivering compressed refrigerant to at least one condenser, from which condenser liquid refrigerant is led to at least one evaporator through at least one restriction element, where the compressor is connected to the evaporator, and where a defroster circuit is arranged for selectively supplying hot refrigerant to said evaporator equipment for defrosting purposes.
  • Defrosting is necessary to remove ice built up on a freezer or a cooler. In most cases it is a question of proper and efficient function of the equipment, but in some cases it is a vital part of the function.
  • One of the latter cases is a plate freezer, where the product is frozen between two metal plates wherein refrigerant is circulated. To be able to remove the product it is necessary to defrost the plates.
  • Defrosting can be done in several ways, with the most common being:
  • Hot gas defrosting is very efficient as heat is delivered where the ice has built up and it is very economical since the heat used is present in the system. Electrical and hot liquid defrosting requires an external power source which hot gas defrosting does not. During hot gas defrosting the cooler/freezer acts as a secondary condenser dispersing the heat otherwise dispersed in the cooling media (usually water or air).
  • cascade systems are becoming more frequent. Due to the high saturation pressure of CO 2 , it is not possible to keep the pressure within the range normally encountered in refrigeration plants while still condensing it against air or water at ambient temperatures. Thus a cascade system is used, wherein a secondary refrigeration plant cools the CO 2 condenser. The secondary refrigeration plant condenses against the available cooling media. The condensing temperature of the CO 2 is usually in the range of-20°C to -5°C.
  • a valve in the outlet controls the defrosting pressure in the evaporator. This valve will close when the pressure is lower than the desired pressure. However, this restricts the liquid condensed during the defrosting from leaving the evaporator, thus resulting in a build up of liquid in the evaporator. The build up of liquid reduces the surface inside the evaporator available for condensing and as such reduces the overall effect of the defrosting.
  • the patent application DK 2001 00310 describes a plant and a process using CO 2 for defrost.
  • This system is a unit that delivers both defrosting and standstill cooling, e.g. keeping system pressure down during standstill.
  • failure of the defrost system would mean that no standstill cooling is available and it is from some classification societies a demand that the standstill cooling is performed by a separate unit as a part of the safety system.
  • the above-mentioned system is connected to the "distribution system", defined as a vessel with gas/liquid equilibrium along with the piping to the consumers e.g. the evaporators. From the application and its definitions it appears that the possible connection points are: A pump separator, a high-pressure receiver, and the piping to the consumers.
  • defrosting compressor Connecting the defrosting compressor to the refrigeration cycle's low-pressure side results in a very large pressure difference, which most industrial refrigeration compressors cannot handle. Furthermore a defrosting compressor connected to the low pressure side needs to be about 4 times bigger (by swept volume) than one connected to the high pressure side to deliver the same defrosting capacity. Standard refrigeration equipment can be used when connecting to the high-pressure side, while this is not the case when connecting to the low-pressure side.
  • the receiver essentially collects liquid from the condenser and will normally not contain the large amounts of gas necessary for defrosting.
  • the suction gas for the compressor is saturated, necessitating a liquid separation. Ensuring that the suction gas contains no liquid is essential for safe compressor operation - especially when using reciprocating compressors.
  • US 4,962,647 comprises a refrigerating circuit apparatus includes a two stage compressor having an upper stage compressing cylinder and a lower stage compressing cylinder, a heat storage tank, an upper stage side variable opening expansion valve and a lower stage side variable opening expansion valve.
  • the upper stage side variable opening expansion valve is controlled towards its closed position for executing a heat storing operation in which heat is discharged from refrigerant to the heat storage tank.
  • the upper stage side variable opening expansion valve is opened and the lower stage side variable opening expansion valve is closed for carrying out a defrosting operation. Heat stored in the heat storage tank is used in the defrosting operation for removing frost accumulated on an external heat-exchanger during the heating operation.
  • the present invention comprises a refrigeration plant as the one described in the opening paragraph, operating with at least one compressor which comprises at least a first compressor section and a second compressor section, which first and second compressor sections can be operating in serial connection during defrost, where the first and second compressor sections can be operating in parallel during normal operation, where the pressure outlet of the second compressor section during defrost is connected to a gas pipe connection which is connected to a refrigerant channel system of said evaporator equipment.
  • a compressor build in sections maybe with a common motor, can operate very flexibly because defrost of evaporators is only necessary in a few minutes with an interval of several hours.
  • the compressor section can operate in parallel in periods with no defrost. If the refrigeration plant operates as a heat pump, defrost may only be necessary in the coldest winter.
  • the second compressor section is being operable to supply defrost gas at elevated pressure and temperature governed by preset or presetable discharge pressure/temperature requirements. In this way special requirements for the cooling plant can bee fulfilled.
  • Defrost can take place in a form depending on the use of the cooling plant. In one situation rapid defrost with a high temperature is the best solution, but in other situations the defrost temperature needs to bee low in order not to damage the food, but the defrost period can bee longer.
  • This invention also relates to a refrigeration system of the cascade type where said defroster circuit comprises a defrost compressor section arranged in a gas pipe connection from the discharge side of said one or more refrigeration compressors or compressor sections to the refrigerant channel system of said evaporator equipment, said defrost compressor being operable to supply defrost gas at elevated pressure and temperature governed by preset or preset able discharge pressure/temperature requirements. At +10°C the CO 2 pressure is 45 bar, which calls for a separate dedicated defrost system.
  • the system according to the invention limits the high pressure to an absolute minimum number of components while employing as many standard components as possible.
  • Using a dedicated defrosting compressor section another pressure level is created with the sole purpose of defrosting. In this way the high pressure can be limited to the defrosting compressor section, the defrost pipe, the evaporator to be defrosted and a few valves at the evaporator.
  • the cascade cooler, refrigeration compressor and associated equipment can be held at the temperature/pressure yielding the most overall efficient plant and still be standard refrigeration components.
  • the defrosting compressor section is connected to the refrigeration compressor outlet.
  • a system according to the invention has an especially dedicated compressor section for defrosting.
  • This defroster compressor section suction gas is the refrigeration compressor discharge gas.
  • the gas has been desuperheated before entering the defrost compressor to avoid too high discharge temperature that could create a problem with lubrication of the defrost compressor.
  • the COP (cooling capacity kW per power consumption kW) of the defrost compressor would be lower and oil cooling would be necessary.
  • Desuperheating (cooling) of the suction gas to the defrosting compressor section has an effect on the overall power consumption of the plant. Two methods of cooling are the most likely; the first one being cooling with the same media used in the secondary systems condenser (air or water) and the other method is using the cascade cooler.
  • a cascade cooler would desuperheat the gas before condensing, so introducing a nozzle in the appropriate place in the cascade cooler would yield a supply of cooled gas.
  • the cooling is performed by the secondary system so power will be required by the secondary system.
  • the gas supplied to the defrosting compressor does not contain liquid. A positive superheat is required to avoid liquid hammer (attempting to compress liquid) in the compressor.
  • the air/water cooled cooler offers some advantages. As mentioned earlier, it is not practically possible to condense the CO 2 against air/water at a normal ambient temperature, but it is possible to use it to cool the gas before entry into the cascade cooler and defrosting compressor. The benefit is that every kW cooled by the cooler does not have to be removed in the cascade cooler. This results in a reduction of both the size, and power consumption of the secondary system. In such a cooler the gas can be cooled to a temperature very close to the ambient temperature, but since the saturation (condensing) temperature is much lower, the gas is still sufficiently superheated to avoid liquid hammer. The selection of one of these two systems will be a question of installation costs versus the savings in running costs.
  • the defrost compressor section can comprise capacity regulation.
  • the condensing temperature determines the suction pressure in the cooling cycle. This pressure is kept constant by the "hot" refrigeration cycle.
  • a controllable bypass valve is used to bypass hot gas back to the cascade cooler.
  • the bypass valve is arranged in a connection from the discharge side of the defrost compressor section and the discharge side of the one or more refrigerating compressors. A precise control of the defrost pressure and temperature is thereby enabled and the bypass valve will smoothen the capacity steps and secure that the pressure does not exceed the maximum design pressure. This control method makes it unnecessary to mount control valves on each cooler to control the pressure during defrost. All defrost control is done by the compressor section and the bypass valve.
  • the defrost pressure/temperature can be set individually for each evaporator by changing the defrost compressor section. In this way the defrost can be optimised for the individual type of evaporator. Some applications can benefit from a more gradual defrost while some need a fast defrost. Considerations when selecting defrosts temperature will include heat loss into the surroundings, water/steam contents in the room air and product quality.
  • the refrigerant outlet from the evaporator equipment can be connected to the suction side of the one or more refrigeration compressors through a liquid operated liquid draining device.
  • thermodynamic liquid drain designed for steam and compressed air application.
  • This device allows liquid to pass and stops gas in much the same way as a float valve mechanism.
  • Float valve mechanisms employ a floating ball but these have been difficult or expensive to get for the high pressure needed.
  • the liquid drain used is simple and can accept the pressures. The benefit is that when the compressor controls the pressure completely, the liquid drain only needs to drain the liquid in the freezer and not concern itself with regulating the pressure. The result is an extremely simple system with an efficient operation.
  • a system as described, wherein the entire gas conductor system from the defrost compressor section through the evaporator equipment and to the drain pipe of the evaporator can generally be without pressure regulating means and will preferably be laid out for operating at pressures not exceeding 50 bar.
  • the gas will, after compression in the defrosting compressor, be condensed in the evaporator to be defrosted.
  • the COP cooling capacity kW per power consumption kW
  • the difference is naturally dependent on the type (refrigerant etc) of the secondary system and running conditions, but in general terms a factor of two is realistic. This means that for every 100 kW used by the defrosting compressor, the power consumption of the secondary system drops with 200 kW with a resulting overall drop of 100 kW.
  • the defrost compressor employed in this system will deliver approximately 600 kW heating. If electrical defrosting is to be used, all 600 kW is needed in electricity, so the comparison is really an increase of 600 kW compared to a drop of 100 kW. If hot glycol is to be used the heating could be extracted in the system (most likely the secondary system's hot side) so the power consumption only increases with the pump power. However, no gain similar to the one described above is achieved.
  • the compressors used are mainly large industrial compressors for industrial cooling purposes, but that the invention can also be used in connection with plants comprising commercial compressors capable of handling the given pressure and temperature.
  • cooling and freezing plants in butcher shops, in supermarkets or in other retail shops can be mentioned as places to use the system.
  • the defrost compressor capacity to supply hot gas to other elements than to a traditional evaporator e.g. to elements consisting of heating/evaporator pipes placed in areas where ice otherwise will built up.
  • the hot gas could also be used for heating.
  • Freezers that need defrosting are often used onboard fishing vessels, and in such plants heating/evaporator pipes can be installed in the floor in the freezing area. In this area there will typically be ice formations, which today is removed or controlled by electrical heating elements. By replacing these elements with heating/evaporator pipes less electrical power is needed and the defrost compressor is used more efficiently whereby energy is saved in the second condensing unit.
  • CO 2 hot gas from the defrost compressor can be used for traditional defrosting, for heating and for defrosing in all places where the temperature is below 10 °C.
  • the freezing system 2 is executed in the traditional manner.
  • the pump separator 4 contains liquid refrigerant at the evaporating temperature.
  • the pumps 6 pump refrigerant liquid to at least one evaporator 8 through the valve station 10.
  • the refrigerant liquid is partially or completely evaporated and returned through a line 26 to the pump separator 4.
  • the gas generated in the evaporator 8 is removed by at least one refrigeration compressor 12, which compresses the gas to the condensing pressure. From the refrigeration compressor 12 the gas is primarily led to the cascade cooler 14 where the gas is condensed before being led back to the pump separator 4.
  • a secondary condensing unit 16 provides cooling for the cascade cooler 14.
  • the freezing system 2, as described here, is prior art technology and is as such not interesting, but the defrosting system is the essence of the invention described here.
  • the compressor 12 is a two section compressor, comprising a common motor 50 connected to a primary compression section 52 and to a defrosting section 54.
  • the defrost compressor section 54 takes suction from the discharge of the refrigeration compressor section 52 (e.g. at condensing pressure) and compresses it to the desired defrost pressure.
  • the gas from the refrigeration compressor section 52 is significantly superheated.
  • This cooler has not been included on the sketch, because the function is not vital to the principal function of the defrost system.
  • the gas cooling could take place in an external heat exchanger or it could take place in the cascade cooler 14. As mentioned this gas cooling is not essential for the principal function of the system 2, but since some energy efficiency issues arise from this, it will be discussed later in detail.
  • the gas is led to the evaporator 8.
  • the gas is led through a conduit 56 comprising a magnetic valve 58 to the liquid/gas "outlet" 22 of the evaporator 8, resulting in a defrosting flow backward in the evaporator 8.
  • a conduit 56 comprising a magnetic valve 58 to the liquid/gas "outlet" 22 of the evaporator 8, resulting in a defrosting flow backward in the evaporator 8.
  • backward defrosting is considered most efficient and thus it is outlined here.
  • backward defrosting is safer since the risk of liquid bullets being shot through the system is reduced.
  • the defrost gas condenses and it is led out through the liquid "inlet" 24 of the evaporator 8.
  • the compressor section 54 capacity regulation will regulate according to the discharge pressure as opposed to the "normal" suction pressure regulation. This method of regulation is common in heat pumps.
  • the suction pressure for the defrosting compressor section 54 e.g. the condensing pressure in the CO 2 circuit
  • the suction pressure for the defrosting compressor section 54 is kept constant by the secondary condensing unit 16. Regulating the pressure with the compressor section 54 while the float valve 28 drains the evaporator 8 (regardless of the pressure) has some benefits:
  • Fig. 2 shows an alternative embodiment for the invention, where the figure differs in having more compressors 70 and 72. These compressors are always operating as cooling compressors, where defrost is carried out by the compressor section 54.
  • Fig. 3 is showing a log (P)-H diagram of defrost according to the invention in cascade systems.
  • the diagram shows the normal refrigeration cycle (34). From evaporating pressure (36) the refrigerant is compressed (38) up to the condensing pressure (40). From the compressor discharge (42) the gas is cooled and eventually condensed before it is flashed back to the evaporating pressure (36).
  • the system according to the invention connects the defrosting compressor section (54) after the refrigeration compressors discharge port (42) and before condensing takes place (44) in the condenser/cascade cooler.
  • the compressor section (54) is compressing (39) the refrigerant to the defrost pressure (45), where the refrigerant remains at a nearly constant pressure (45) during defrost of an evaporator. After end of defrost the pressure of the refrigerant is reduced (43) to the normal condensation pressure (40).
  • the defrost compressor is connected at the refrigeration compressors suction side (46) or after the condenser/cascade cooler (48).

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Defrosting Systems (AREA)
EP03026471A 2002-11-21 2003-11-20 Dégivrage par gaz chaud pour installations frigorifiques Withdrawn EP1422487A3 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DKPA200201801 2002-11-21
DK200201801 2002-11-21

Publications (2)

Publication Number Publication Date
EP1422487A2 true EP1422487A2 (fr) 2004-05-26
EP1422487A3 EP1422487A3 (fr) 2008-02-13

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EP03026471A Withdrawn EP1422487A3 (fr) 2002-11-21 2003-11-20 Dégivrage par gaz chaud pour installations frigorifiques

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006129034A2 (fr) * 2005-06-02 2006-12-07 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Procede de refrigeration d'une charge thermique
EP1775531A1 (fr) * 2005-10-12 2007-04-18 GTI Koudetechnik B.V. Appareil et système de refroidissement et/ou de congélation et de dégivrage
EP2019272A2 (fr) * 2007-07-23 2009-01-28 Hussmann Corporation Collecteur et échangeur à chaleur combinés pour fluide frigorigène secondaire
EP2135017A1 (fr) * 2007-03-09 2009-12-23 Carrier Corporation Prévention de la solidification d'un fluide frigorigène
WO2009158612A2 (fr) * 2008-06-27 2009-12-30 Carrier Corporation Procédé de dégivrage par gaz chaud
CN106705516A (zh) * 2017-01-27 2017-05-24 广州市粤联水产制冷工程有限公司 渐进式排液装置及热气融霜系统
FR3089603A1 (fr) * 2018-12-06 2020-06-12 Beg Ingenierie Installation de réfrigération

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4962647A (en) 1988-06-30 1990-10-16 Kabushika Kaisha Toshiba Refrigerating circuit apparatus with two stage compressor and heat storage tank

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US3074249A (en) * 1960-06-15 1963-01-22 Ray M Henderson Refrigeration system and apparatus having a heating cycle and a cooling cycle
US3285500A (en) * 1964-05-25 1966-11-15 Borg Warner Combination single and dual stage compressor
JPS5485455A (en) * 1977-12-21 1979-07-07 Mitsubishi Electric Corp Refrigerating system
JP2513700B2 (ja) * 1987-06-30 1996-07-03 株式会社東芝 空気調和装置
US5600961A (en) * 1994-09-07 1997-02-11 General Electric Company Refrigeration system with dual cylinder compressor
DE19920726A1 (de) * 1999-05-05 2000-11-09 Linde Ag Kälteanlage
JP4441965B2 (ja) * 1999-06-11 2010-03-31 ダイキン工業株式会社 空気調和装置
EP1409936B1 (fr) * 2001-06-13 2006-12-13 York Refrigeration APS Degivrage a l'aide d'un gaz chaud de co2 dans les systemes de refrigeration en cascade

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4962647A (en) 1988-06-30 1990-10-16 Kabushika Kaisha Toshiba Refrigerating circuit apparatus with two stage compressor and heat storage tank

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2886719A1 (fr) * 2005-06-02 2006-12-08 Air Liquide Procede de refrigeration d'une charge thermique
WO2006129034A3 (fr) * 2005-06-02 2007-10-11 Air Liquide Procede de refrigeration d'une charge thermique
WO2006129034A2 (fr) * 2005-06-02 2006-12-07 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Procede de refrigeration d'une charge thermique
EP1775531A1 (fr) * 2005-10-12 2007-04-18 GTI Koudetechnik B.V. Appareil et système de refroidissement et/ou de congélation et de dégivrage
EP2135017A1 (fr) * 2007-03-09 2009-12-23 Carrier Corporation Prévention de la solidification d'un fluide frigorigène
EP2135017A4 (fr) * 2007-03-09 2010-03-10 Carrier Corp Prévention de la solidification d'un fluide frigorigène
US7900467B2 (en) 2007-07-23 2011-03-08 Hussmann Corporation Combined receiver and heat exchanger for a secondary refrigerant
EP2019272A2 (fr) * 2007-07-23 2009-01-28 Hussmann Corporation Collecteur et échangeur à chaleur combinés pour fluide frigorigène secondaire
EP2019272A3 (fr) * 2007-07-23 2010-02-24 Hussmann Corporation Collecteur et échangeur à chaleur combinés pour fluide frigorigène secondaire
WO2009158612A2 (fr) * 2008-06-27 2009-12-30 Carrier Corporation Procédé de dégivrage par gaz chaud
WO2009158612A3 (fr) * 2008-06-27 2010-04-22 Carrier Corporation Procédé de dégivrage par gaz chaud
CN106705516A (zh) * 2017-01-27 2017-05-24 广州市粤联水产制冷工程有限公司 渐进式排液装置及热气融霜系统
CN106705516B (zh) * 2017-01-27 2023-04-28 广州市粤联水产制冷工程有限公司 渐进式排液装置及热气融霜系统
FR3089603A1 (fr) * 2018-12-06 2020-06-12 Beg Ingenierie Installation de réfrigération
WO2020115449A3 (fr) * 2018-12-06 2020-10-08 Beg Ingenierie Installation de réfrigération

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