DK174257B1 - Installations and methods where CO2 is used as a refrigerant and as a working medium for defrosting - Google Patents
Installations and methods where CO2 is used as a refrigerant and as a working medium for defrosting Download PDFInfo
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- DK174257B1 DK174257B1 DK200100310A DKPA200100310A DK174257B1 DK 174257 B1 DK174257 B1 DK 174257B1 DK 200100310 A DK200100310 A DK 200100310A DK PA200100310 A DKPA200100310 A DK PA200100310A DK 174257 B1 DK174257 B1 DK 174257B1
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- pressure
- distribution system
- cooling equipment
- refrigerant
- cooling
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- 239000003507 refrigerant Substances 0.000 title claims description 38
- 238000010257 thawing Methods 0.000 title claims description 26
- 238000000034 method Methods 0.000 title claims description 22
- 238000009434 installation Methods 0.000 title claims description 8
- 238000001816 cooling Methods 0.000 claims description 33
- 239000007788 liquid Substances 0.000 claims description 22
- 238000005057 refrigeration Methods 0.000 claims description 9
- 239000003990 capacitor Substances 0.000 claims description 2
- 230000000694 effects Effects 0.000 claims description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 16
- 229910021529 ammonia Inorganic materials 0.000 description 8
- 230000008014 freezing Effects 0.000 description 6
- 238000007710 freezing Methods 0.000 description 6
- 238000009833 condensation Methods 0.000 description 5
- 230000005494 condensation Effects 0.000 description 5
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 4
- 238000001704 evaporation Methods 0.000 description 4
- 238000005265 energy consumption Methods 0.000 description 3
- 238000007906 compression Methods 0.000 description 2
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 230000006835 compression Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 230000006837 decompression Effects 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 230000001605 fetal effect Effects 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 239000003380 propellant Substances 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
Classifications
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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
- 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
- F25B25/00—Machines, plants or systems, using a combination of modes of operation covered by two or more of the groups F25B1/00 - F25B23/00
- F25B25/005—Machines, plants 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
-
- 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
- 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
- F25B2309/00—Gas cycle refrigeration machines
- F25B2309/06—Compression machines, plants or systems characterised by the refrigerant being carbon dioxide
- F25B2309/061—Compression machines, plants or systems characterised by the refrigerant being carbon dioxide with cycle highest pressure above the supercritical pressure
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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)
- Crystals, And After-Treatments Of Crystals (AREA)
Description
DK 174257 B1 iDK 174257 B1 i
Den foreliggende opfindelse angår et køleanlæg, hvor C02 anvendes som kølemiddel og som arbejdsmedte ved afrimning og med et fordelmgssystem for kølemidlet samt køleudstyr på forbrugssted for køleeffekt Opfindelsen angår også en fremgangsmåde, hvor C02 anvendes som kølemiddel og som arbejdsmedte ved afrimning, og hvor kø-5 lemediet ledes gennem et fordelingssystem samt gennem et køleudstyr på forbrugssted for køleeffektThe present invention relates to a refrigeration plant in which CO 2 is used as a refrigerant and as a working medium for defrosting and with a distribution system for the refrigerant as well as refrigeration equipment at the place of consumption for cooling effect. The invention also relates to a method in which CO 2 is used as refrigerant and as a working medium for defrosting. The cooling medium is passed through a distribution system as well as through a cooling device at the cooling power consumption site
Som kølemiddel i fryseanlæg og frostrum anvendes i dag som oftest ammoniak i totnns anlæg eller på mindre anlæg ettnns R22, som ikke længere er tilladt i nye an-10 læg Anvendelse af ammoniak i fryseudstyr er en velafprøvet og driftsikker teknologi, men visse steder kan det være uønsket at have ammoniakken i arbejdslokaler Ombord på fiskeskibe vil installation af pligtigt sikkerhedsudstyr medføre en betydelig forøgelse af anlægsomkostningerne 15 C02 udgør et godt alternativ til R22, ammoniak og andre kølemidler i fryseudstyr og frostrum på både landanlæg og skibsanlæg Udover en miljømæssig gevinst kan der med C02 tillige opnås øget fiysekapacitet og under visse betingelser reduceret energiforbrug, og pladskrav til kølekompressoranlægget kan mindskes Til gengæld adskiller C02 sig væsentligt fra traditionelle kølemidler på en række punkter, som der skal tages 20 hensyn til i udformningen af selve fryseudstyret samt udformningen af selve køleanlæggetAs refrigerant in freezer systems and freezer compartments, ammonia is usually used today in two-unit plants or on smaller plants one-two R22, which is no longer allowed in new plants. Use of ammonia in freezing equipment is a well-tested and reliable technology, but in some places it can be undesirable to have the ammonia in workrooms On board fishing vessels, the installation of mandatory safety equipment will significantly increase the cost of construction 15 C02 represents a good alternative to R22, ammonia and other refrigerants in freezing equipment and freezer space at both onshore and ship systems. C02 also achieves increased freezing capacity and under certain conditions reduced energy consumption, and space requirements for the refrigeration compressor system can be reduced. In contrast, C02 differs significantly from traditional refrigerants at a number of points, which must be taken into account in the design of the freezer itself as well as the design of the cooling unit itself.
Det kritiske punkt for C02 ligger ved 31°C og et tryk på 72 bar Disse termodynamiske forhold adskiller sig markant fra traditionelt anvendte kølemidler, og dette forhold 25 har stor indflydelse på valg og udformning af komponenter og anlægsopbygmng Trykket ved en given temperatur er højere end for traditionelt anvendte kølemidler som ammoniak, HCFC og HFC Beliggenheden af det kritiske punkt betyder, at C02 energimæssigt generelt er bedst egnet til lavtemperaturanvendelser i kaskade med for eksempel ammoniak eller andet kølemiddel Ved udformning af kompressorer, var-30 mevekslere, ventiler, beholdere, rør og fleksible slanger skal der dog nødvendigvis tages højde for det højere tryk DK 174257 B1 2The critical point for CO 2 is at 31 ° C and a pressure of 72 bar. These thermodynamic conditions differ markedly from traditionally used refrigerants, and this ratio 25 has a great influence on the selection and design of components and plant structure. The pressure at a given temperature is higher than for traditionally used refrigerants such as ammonia, HCFC and HFC The location of the critical point means that CO2 is generally best suited for low-temperature applications in cascades with, for example, ammonia or other refrigerants When designing compressors, heat exchangers, valves, containers, pipes and flexible hoses, however, the higher pressure must necessarily be taken into account DK 174257 B1 2
Under dnft af køleudstyr/fryseudstyr og ffostrum er temperaturen dog normalt så lav, at trykket er mindre end 20 Bar, og der kan derfor anvendes standardkomponenter i et sådant anlæg 5 Det højere tryk har imidlertid også en gunstig afsmitning på forskellige egenskaber Densiteten i gasfasen er langt større, og temperaturændnngen ved tryktab er langt mindre for C02 end for andre kølemidler Derved kan dimensioner i udstyr på gassiden reduceres 10 Ved kendte anlæg kan C02 anvendes på lavtemperatur-tnnnet ved brug af to principielt forskellige metoder, nemlig bnneløsning og kaskadeløsning, der vil blive forklaret nærmere i det følgendeHowever, under refrigeration / freezing equipment and fetal room, the temperature is usually so low that the pressure is less than 20 Bar, and therefore standard components can be used in such a plant. However, the higher pressure also has a favorable contamination of various properties. far greater, and the temperature change at pressure loss is far less for CO 2 than for other refrigerants. Thus, dimensions of gas side equipment can be reduced. 10 In known systems, CO 2 can be applied to the low temperature tunnel using two fundamentally different methods, namely bed solution and cascade solution which will will be explained in more detail below
Ved de kendte anlæg er der flere ulemper, herunder ved afrimning og stigende tryk ved stilstand 15At the known plants, there are several disadvantages, including defrosting and increasing pressure at standstill 15
Fordampere i fryseudstyr (f eks pladefrysere eller luftkølere) skal med jævne mellemrum afrimes for fortsat at kunne fungere optimaltEvaporators in freezer equipment (eg plate freezers or air coolers) must be defrosted periodically to continue to function optimally
Med traditionelle kølemidler anvendes normalt varmgas fra kompressorer til afrim-20 ningen af ftyseudstyr, idet trykgas fra kompressorerne ledes til fryseudstyret, hvor gassen typisk kondenserer ved temperaturer mellem 20°C og 30°C og herved afsmelter nm på overfladerneWith conventional refrigerants, normally hot gas from compressors is usually used for defrosting refrigeration equipment, with compressed gas being fed from the compressors to the freezing equipment, where the gas typically condenses at temperatures between 20 ° C and 30 ° C, thereby melting nm on the surfaces.
Ved anvendelse af C021 kaskade anlæg eller som sekundært kølemiddel er der ikke på 25 samme måde C02 trykgas til rådighed ved en passende høj kondensenngstemperatur, og anvendelsen af C02 har bl a derfor været begrænset indtil videreWhen using C021 cascading systems or as a secondary refrigerant, C02 compressed gas is not in the same way available at a suitably high condensation temperature, and the use of C02 has therefore been limited to date.
Der findes alternative løsninger, hvor der anvendes elstave, intern varm væske (for eksempel glykol) eller overbrusmng med varmt vand til afrimning af C02 systemer 3 DK 174257 B1There are alternative solutions using electricity rods, internal hot liquid (for example glycol) or hot water sprinkling for defrosting CO 2 systems 3 DK 174257 B1
Metode Praktisk anvendelighed KommentarerMethod Practical Applicability Comments
Elektrisk afrimning + luftkølere -Energiforbrug 4 x varm gas (+) pladefrysere -1,5 til 2 gange øgede varmevekslerstørrelseElectric Defrost + Air Coolers - Energy Consumption 4 x hot gas (+) plate freezers -1.5 to 2 times increased heat exchanger size
Varm overbrusmng - luftkølere -Uønsket vand i kanaler og - pladeftysere arbejdslokaler - Risiko for beskadigelse af produkterHot sprinkling - air coolers - Unwanted water in ducts and - Plasma heaters work rooms - Risk of product damage
Varm bnne cirkulation (+) luftkølere -Min 2 gange øgedeHot open circulation (+) air coolers -Min 2 times increased
Intern (+) pladeftysere varmevekslerstørrelseInternal (+) plate heat exchanger size
Endvidere er der kendskab til en metode, hvor C02 anvendes som arbejdsmedie ved afrimningen Metoden består i, at C02 fra pumpebeholderen pumpes op til højt tryk 5 (f eks 65 bar) i en fordampningsbeholder, hvor det opvarmes og fordamper ved varmeveksling med varm gas fra primærsiden (for eksempel R22 eller ammoniak) Den varme C02 gas under højt tryk føres herfra videre til køleanlægget, der skal afrimes, hvor den kondenserer og igen ekspanderes tilbage hl pumpebeholderen Metoden er beskrevet nærmere i patentansøgningen GB 2 258 298 A, (03-02-1993), Appl no 10 9215183 6Furthermore, a method is known in which CO 2 is used as a working medium for defrosting. The method consists in pumping CO 2 from the pump vessel up to high pressure 5 (eg 65 bar) in an evaporating vessel, where it is heated and evaporated by heat exchange with hot gas from primary side (for example R22 or ammonia) The hot CO 2 gas under high pressure is then passed on to the cooling system, which must be defrosted, where it condenses and again expanded back into the pump container. The method is described in detail in patent application GB 2 258 298 A, (03-02 1993), Appl No. 10 9215183 6
Under stilstand vil trykket i systemet stige på grund af varmeindfald fra omgivelserne Ved en omgivelsestemperatur på 25°C er mætningstrykket 64 bar Hvis kølemiddel-fyldningen skal opbevares i anlægget ved dette tryk, vil det indebære, at alle kompo-15 nenter skal udlægges for dette tryk For væskebeholdere, som receiver og lavtryksvæskeudskiller, vil det betyde en uacceptabel høj fremstillingspris, og systemer, hvor temperaturen holdes på eksempelvis 0°C eller -10°C under stilstand, er langt mere attraktive 20 Der er kendskab hl en metode US patent nr 6 112 532, hvor C02 opbevares i en højtryksbeholder under stilstand Trykket i beholderen holdes nede ved at køle væsken indvendigt ved hjælp af kølemiddelspiral ved lavt tryk Metoden anvender en høj og DK 174257 B1 4 en lav trykskreds C02 fyldningen opbevares hovedsageligt i højtryksdelen under stilstand Samtidig forsynes forbrugsstederne med kold lavtryksvæske/gas under stilstand 5 Ved den her beskrevne metode holdes hele fyldningen ved et lavt tryk, som eksisterer i hele kølemiddelfordelingsdelen 40 samt forbrugsstederne 44 US patent nr 6 112 532 omhandler principielt en spiralkølet væskebeholder som kan opbevare C02 under kontrolleret højt tryk, som er lig med eller højere end mætmngs-10 trykket ved omgivelsernes temperaturDuring standstill, the pressure in the system will increase due to ambient heat input At an ambient temperature of 25 ° C, the saturation pressure is 64 bar. If the refrigerant charge is to be stored in the system at this pressure, all components must be laid out for this. pressure For liquid containers, such as receiver and low-pressure liquid separator, this will mean an unacceptably high manufacturing cost, and systems where the temperature is kept at, for example, 0 ° C or -10 ° C at a standstill, are far more attractive. 6 112 532, where C02 is stored in a high-pressure container during standstill The pressure in the container is kept down by cooling the liquid internally by means of a low-pressure refrigerant coil. The method uses a high and DK 174257 B1 4 a low pressure circuit C02 the filling is mainly stored in the high-pressure section. supply the consumable with cold low-pressure liquid / gas at a standstill 5 By the method described here, keep The entire low-pressure filling that exists throughout the refrigerant distribution portion 40 as well as the consumable sites 44 U.S. Patent No. 6,122,532 basically discloses a spirally cooled liquid container capable of storing CO 2 under controlled high pressure equal to or higher than the saturation pressure at ambient pressure. temperature
Ved den her beskrevne metode vil hele C02 fyldningen holdes ved et tryk mindre end eller hg mætmngstrykket omgivelsernes temperatur 15 Det er formålet med den foreliggende opfindelse at anvise et anlæg samt en fremgangsmåde, hvor C02 kan anvendes såvel hl kølemiddel som til afrimning, og hvor ulemperne ved de kendte anlæg er undgåetIn the method described herein, the entire CO 2 filling will be kept at a pressure less than or above the saturation pressure of ambient temperature. It is the object of the present invention to provide a system and a method in which CO 2 can be used for both refrigerant and defrost, and where the disadvantages at the known plants are avoided
Dette opnås ifølge den foreliggende opfindelse med et anlæg, der er særpræget ved, at 20 det omfatter en unit, der er forbundet mellem fordelingssystemet og køleudstyret, at unitten omfatter en højtrykskompressor, hvis sugeside er forbundet med fordelingssystemet for at suge gasformigt kølemidddel ud af fordelingssystemet ved lavt tryk, og hvis trykside omfatter et ventilarrangement, som kan sikre forbindelse til en første ledningskreds, der indeholder køleudstyret samt en afhmmngstrykregulator, og som 25 leder C02 under højt tryk gennem en del af køleudstyret for at afrime denne del og videre gennem afrimningstrykregulatoren og retur til fordelingssystemet ved et lavt tryk, der er etableret i afrimningstrykregulatoren og at de øvrige dele af køleudstyret stadig er koblet til fordelingssystemet og virker ved lavt tryk 30 Fremgangsmåden ifølge opfindelsen er særpræget ved, at afrimning foretages ved, at en første kreds anvendes, hvor C02 under højt tryk ledes gennem køleudstyret idet gasformigt C02 ved lavt tryk udtages fra fordelingssystemet og kompnmeres i en høj- 5 DK 174257 B1 trykskompressor, at det gasformige C02 ved højt tryk ledes gennem en del af køleudstyret for afrimning heraf, at det gasformige C02 ledes gennem en trykregulenng for at ledes retur til fordelingssystemet ved lavt tryk og at disse tnn gentages for alle dele af køleudstyret indtil afrimning er udført 5This is achieved in accordance with the present invention with a system characterized in that it comprises a unit connected between the distribution system and the cooling equipment, the unit comprising a high pressure compressor whose suction side is connected to the distribution system to suck gaseous refrigerant out of the distribution system. at low pressure, and whose pressure side comprises a valve arrangement which can ensure connection to a first wiring circuit containing the cooling equipment and a pressure relief regulator, and which conducts high pressure CO 2 through a portion of the cooling equipment to defrost this portion and further through the defrost pressure regulator and return to the distribution system at a low pressure established in the defrost pressure regulator and that the other parts of the cooling equipment are still coupled to the distribution system and operate at low pressure 30 The method of the invention is characterized in that defrosting is performed by using a first circuit where CO 2 under high pressure is passed through the cooling equipment as gaseous CO2 at low pressure is taken out of the distribution system and is compressed in a high pressure compressor that the gaseous CO2 at high pressure is passed through a part of the cooling equipment for defrosting thereof, that the gaseous CO2 is passed through a pressure regulator. return to the low pressure distribution system and repeat these tests for all parts of the refrigeration equipment until defrosting is completed 5
Med et sådant anlæg og en sådan metode kan C02 under højt tryk benyttes til afrimning, og kun et fåtal af anlæggets komponenter behøver at være udlagt til et sådant højt tryk Samtidig kan fordelene ved C02 som kølemiddel benyttes, og der er således kun behov for C02 som det eneste arbejdsmedie i anlægget/ved fremgangsmåden 10With such a plant and method, CO 2 under high pressure can be used for defrosting, and only a few of the plant components need to be laid to such a high pressure. At the same time, the advantages of CO 2 as a refrigerant can be used and thus only CO 2 is needed. as the only working medium in the plant / by the process 10
Det særlig nye ved opfindelsen er især systemet, der skaber muligheden for kun at anvende C02, og som omfatter en unit, hvorved systemet adskiller sig fra eksisterende systemer, ved at der varetages både afrimning under drift af fryseudstyr (afrimning) og samtidig forhindres, at trykket i hovedsystemet under stilstand (trykbegrænsning) 15 overstiger et givet maksimum (f eks 25 bar)Particularly new in the invention is the system, which creates the possibility of using only CO 2, and which comprises a unit whereby the system differs from existing systems by both defrosting during operation of freezing equipment (defrosting) and at the same time preventing the pressure in the main system during standstill (pressure limitation) 15 exceeds a given maximum (eg 25 bar)
Ifølge en yderligere udførelselsesform er apparatet således særpræget ved, at ventilarrangementet tillige kan sikre forbindelse til en anden ledningskreds, der indeholder en kondensator samt en ekspansionsventil, og som leder C02 under lavt tryk tilbage .til 20 fordelingssystemet ved stilstand, således at unitten er indrettet for integreret afrimning afkøleudstyret og stilstandstrykbegrænsningAccording to a further embodiment, the apparatus is thus characterized in that the valve arrangement can also ensure connection to another wiring circuit containing a capacitor and an expansion valve, which returns C02 under low pressure to the distribution system at a standstill, so that the unit is arranged for integrated defrost cooling equipment and standstill pressure limitation
Ifølge en specifik udførelsesform er apparatet særpræget ved, at unittens sugeside er forbundet med fordelingssystemet via en pumpebeholder eller en receiver 25According to a specific embodiment, the apparatus is characterized in that the suction side of the unit is connected to the distribution system via a pump container or a receiver 25
Ifølge en yderligere udførelsesform er fremgangsmåden ifølge opfindelsen særpræget, ved, at stilstandsdnft etableres ved, at en anden kreds anvendes, hvor C02 under lavt tryk ledes gennem fordelingssystemet og køleudstyret 30 Systemet ifølge opfindelsen adskiller sig fra andre kendte afhmningssystemer ved - at omfatte en unit, som kan anvendes som afrimning og stilstandstrykbegrænser på en vilkårlig anlægsudformning, DK 174257 B1 6 - at unitten kan anvendes som plug-on unit til et eksisterende anlæg eller opbygges som en integreret del af hele anlægget - at C02 anvendes som det eneste arbejdsmedie i forbindelse med afrimning og stil-standstrykbegrænsnmg, 5 - at varm C02 gas produceres ved kompression, - at hele C02 fyldningen opbevares på væskeform i lavtryksbeholder ved et givet indstillingstryk mindre end mætnmgstrykket ved omgivelsernes temperatur, - at mgen højtryksbeholdere er nødvendige, - at der er en begrænset udstrækning af højtrykssiden, 10 - at der ikke er nsiko for lækage af C02 under højt tryk ind i pnmær kølekredsen, og - at der ikke er nsiko for lækage af pnmær kølemiddel md i C02 kølekredsenAccording to a further embodiment, the method according to the invention is characterized in that standstill power is established by the use of a second circuit, where CO 2 is passed under low pressure through the distribution system and the cooling equipment. which can be used as defrosting and standstill pressure limiter on any system design, DK 174257 B1 6 - that the unit can be used as a plug-on unit for an existing system or built as an integral part of the whole system - that C02 is used as the only working medium in connection with defrosting and standstill pressure limitation, 5 - that hot CO 2 gas is produced by compression, - that the entire CO 2 filling is stored in liquid form in a low pressure vessel at a given setting pressure less than the saturation pressure at ambient temperature, extension of the high pressure side, 10 - that there is no e is a risk of leakage of C02 under high pressure into the refrigerant circuit, and - there is no risk of leakage of refrigerant in the C02 refrigerant circuit
Opfindelsen vil i det følgende blive forklaret nærmere under henvisning til den medfølgende tegning, hvor 15 fig 1 viser et billede af en første udførelsesform for et anlæg ifølge opfindelsen, udformet som et pumpecirkulationssystem, fig 2 viser et billede af en anden udførelsesform for et anlæg ifølge opfindelsen, udformet som et kaskadesystem, 20 fig 3 viser et billede af en tredje udførelsesform for et anlæg ifølge opfindelsen, udformet som et direkte ekspansionssystem, og fig 4 viser et skematisk billede af en principiel opbygning af et anlæg ifølge opfindelsen 25 I tegningens forskellige figurer vil identiske eller tilsvarende elementer blive betegnet med samme henvisningsbetegnelse, og der vil derfor ikke blive givet en specifik forklaring af alle elementer i forbindelse med hver figurThe invention will be explained in more detail below with reference to the accompanying drawing, in which: Fig. 1 shows a view of a first embodiment of a plant according to the invention, designed as a pump circulation system; Fig. 2 shows a picture of a second embodiment of a plant according to the invention. Fig. 3 shows a view of a third embodiment of a plant according to the invention, designed as a direct expansion system, and Fig. 4 shows a schematic view of a principle structure of a plant according to the invention. In the various figures of the drawing identical or similar elements will be denoted by the same reference designation, and therefore no specific explanation of all elements associated with each figure will be given.
Den nedenfor beskrevne unit er en plug-on løsning, som kan anvendes i både pumpe-30 cirkulationssystemer (figur 1), kaskadeløsninger (figur 2) og direkte ekspansionssystemer (figur 3) 7 DK 174257 B1 C02 kan anvendes på lavtemperatur-trinnet som såkaldt sekundært kølemiddel, som pumpes fra en pumpebeholder 10 til forbrugsstederne, hvor C02 enten fordamper helt, delvist eller kun bliver opvarmet, som vist i figur 1 Afhængig af kølemiddeltype og temperaturmveauer kan det øverste trin udelades 5The unit described below is a plug-in solution that can be used in both pump circulation systems (Figure 1), cascade solutions (Figure 2) and direct expansion systems (Figure 3). The DK1202 can be used at the low temperature stage as so-called secondary refrigerant, which is pumped from a pump container 10 to the consumption points, where CO2 is either completely evaporated, partially or only heated, as shown in Figure 1 Depending on the type of refrigerant and temperature levels, the upper step can be omitted 5
Metoden kræver et traditionelt køleanlæg (f eks ammoniak), hvor fordamperen 11 anvendes til at kondensere/afkøle C02 efter fordampmng/'opvarmmng i forbrugsstederne Udformning af anlægget på denne måde betyder, at der kun skal anvendes en pumpe 14 til at cirkulere C02 10The method requires a traditional refrigeration system (e.g. ammonia), where the evaporator 11 is used to condense / cool the CO2 after evaporation / heating in the consumption points. Design of the system in this way means that only one pump 14 has to be used to circulate the CO2 10.
Alternativt kan C02 anvendes i kaskade med et andet primært kølemiddel, som vist i figur 2 og 3 Lavtrykstnnnet er her opbygget omkring en C02 kompressor, som kondenserer op imod en kaskadekøler 20 med fordampende primær kølemiddel på den anden side 15 I figur 2 ekspanderes C02 væske fra receiveren 21 gennem ventilen 17 til en lavtryks-væskeudskiller/pumpebeholder 10 Under normal drift er sugeventilen 18 åben og C02 kompressoren 22 bortleder den fordampende COz mængde Kølemiddel distribueres ved hjælp af en pumpe 14 til forbrugsstederne 44, hvor C02 fordamper delvist 20 I figur 3 er ekspanderes C02 væske fra receiveren 21 direkte ud i fordamperne 44 gennem ekspansionsorganeme 19 Princippet kaldes direkte ekspansion, og trykforskellen mellem høj og lavtrykssiden fungerer som drivmiddel ved distribution afkølemiddel til forbrugsstederne, hvor C02 fordamper fuldstændigt 25Alternatively, CO 2 can be used in cascade with another primary refrigerant, as shown in Figures 2 and 3. The low pressure network is here built around a CO 2 compressor condensing up against a cascading cooler 20 with evaporating primary refrigerant on the other hand. In Figure 2, CO 2 liquid is expanded. from the receiver 21 through the valve 17 to a low pressure liquid separator / pump container 10 During normal operation, the suction valve 18 is open and the CO 2 compressor 22 discharges the evaporating CO 2 amount of refrigerant distributed by a pump 14 to the consuming points 44, where CO 2 partially evaporates 20 In Figure 3 For example, the C02 liquid from the receiver 21 is expanded directly into the evaporators 44 through the expansion means 19 The principle is called direct expansion, and the pressure difference between the high and low pressure side acts as a propellant in distributing refrigerant to the consumption sites, where C02 completely evaporates 25
Figur 4 viser skematisk, hvorledes et anlæg ifølge opfindelsen indgår i samspil med de øvrige dele af et køleanlægFigure 4 shows schematically how a system according to the invention interacts with the other parts of a cooling system.
Ved fordelingssystemet 40 forstås i denne sammenhæng en beholder med ligevægt 30 mellem væske og damp, sammen med det rørsystem, hvor igennem kølemiddel distribueres til forbrugssteder 44, hvor kølemidlet helt eller delvist fordamper Beholderen kan være en højtryksbeholder også kaldet receiver 21, en lavtryksvæskeudskiller med DK 174257 B1 8 naturlig cirkulation (gravitations drevet) eller en lavtryksvæskeudskiller 10 med pumpecirkulationIn this context, the distribution system 40 is understood to mean a container of equilibrium 30 between liquid and vapor, together with the piping system through which refrigerant is distributed to consumption points 44, where the refrigerant can completely or partially evaporate. The container can be a high pressure container also called receiver 21, a low pressure liquid separator with DK. 174257 B1 8 natural circulation (gravity driven) or a low pressure liquid separator 10 with pump circulation
Opfindelsen er fordelagtig ved at kunne tilkobles fordelingssystemet på en vilkårligt S anlægsudformning Sugesiden 31 skal tilsluttes på gassiden af fordelingssystemets væskebeholder, og afgangssiden 33 tilsluttes på gas eller væskesiden af fordelingssystemets væskebeholderThe invention is advantageous in being able to be connected to the distribution system in any system configuration. The suction side 31 must be connected to the gas side of the distribution system's liquid container and the outlet side 33 to be connected to gas or the liquid side of the distribution system's liquid container.
Afrimningsfunktionen kræver yderligere en tilslutning af varmgas ledningen 32 på 10 fordampernes 44 afgangsside I den viste figur kan højtemperaturtnnnet 42 og varmevekslingen 43 udelades, så processen foretages i et tnn 41 15 Bemærk at ventilarrangementer i figurerne 1 til 3 ikke er fuldstændige af hensyn til overskueligheden af tegningerne Med det givne detaljenngsmveau bør pnncippet være forståeligt for en fagmand på områdetThe defrost function further requires a connection of the hot gas line 32 on the outlet side of the 10 evaporators 44 In the figure shown, the high temperature network 42 and the heat exchange 43 can be omitted, so that the process is carried out in a tank 41 15 Note that valve arrangements in figures 1 to 3 are not complete for reasons of The drawings With the given detailed approach, the concept should be understandable to a person skilled in the art.
Den integrerede unit 30 afgrænset af den stiplede linie i figur 1, 2 og 3, er opbygget 20 omknng en C02 kompressor 7, der kan arbejde med et afgangstryk på mindst 80 bar Sugesiden 31 tilsluttes det eksisterende køleanlægs kølemiddelfordelmgsdelThe integrated unit 30 delimited by the dotted line in Figures 1, 2 and 3 is constructed 20 about a CO 2 compressor 7 capable of operating with a discharge pressure of at least 80 bar The suction side 31 is connected to the existing refrigerant distribution part of the existing refrigeration system.
Unitten består yderligere af en magnetventil 1 til valg af afhmmngsfunktion, en magnet ventil 2 til valg af trykbegrænsningsfunktion, en afhmningstrykregulator 3, en 25 varm gas køler/ kondensator 4, en ekspansionsventil 5 samt en pressostat 6 I figur 1,2 og 3 er pnncippet vist, hvor C02-gas anvendes som eneste arbejdsmiddel Gassen kompnmeres direkte fra pumpebeholderen 10 eller fra receiveren 21 ved hjælp af C02 kompressoren 7, således at der ikke tilføres energi fra pnmærsiden eller elek-30 tnske varmeafgivere til C02 systemet 9 DK 174257 B1The unit further consists of a solenoid valve 1 for selecting the relief function, a magnetic valve 2 for the selection of pressure limiting function, a decompression pressure regulator 3, a 25 hot gas cooler / condenser 4, an expansion valve 5 and a pressure switch 6 In figures 1,2 and 3 shown where CO 2 gas is used as the only working means The gas is compressed directly from the pump container 10 or from the receiver 21 by means of the CO 2 compressor 7, so that no energy is supplied from the pump side or electric heat generators to the CO 2 system 9 DK 174257 B1
Det overordnede afrimingspnncip fremgår fra figur 1 og 2 Under afrimning åbnes ventil 1, og ventil 2 lukkes Kompressoren 7 suger kold gas fra pumpebeholderen 10, og trykket på afgangssiden holdes konstant ved hjælp af regulatoren 3 (eksempelvis 60 bar, svarende til en kondensenngstemperatur på 20°C i fordamperen, der skal afn-5 mes) Før afrimningen finder sted, lukkes ventilen 8, og samtidig åbnes hovedventilen 9 Varm gassen føres gennem kontraventilen 25 til fordamperen, der skal afrimes, hvor den kondenserer C02 beholderen 10 kan under afrimningen afspærres fra rekondense-10 nngsveksleren 11 ved hjælp af ventilerne 12 og 13The overall defrost pin is shown in Figures 1 and 2 During defrost, valve 1 is opened and valve 2 is closed. Compressor 7 sucks cold gas from pump vessel 10 and the discharge side pressure is kept constant by means of the regulator 3 (e.g. 60 bar, corresponding to a condensation temperature of 20 ° C in the evaporator to be removed) Before defrosting, valve 8 is closed and at the same time the main valve 9 is opened. The hot gas is passed through the check valve 25 to the evaporator to be defrosted where it condenses the CO2 container 10 during defrosting. the recondensation exchanger 11 by means of the valves 12 and 13
Under afrimningen presses først den kolde væske og derefter kondensatet „gennem hovedventilen 9, hvorfra det ekspanderes tilbage til trykket væskebeholderen 10 eller C02 receiveren 21 15During the defrost, the cold liquid is first pressed and then the condensate "through the main valve 9, from which it is expanded back to the pressure liquid container 10 or the CO2 receiver 21 15
Selve afrimningskonceptet med varm gas tilførelse, kondensering og ekspansion er velkendt fra traditionelle kølemidlerThe actual defrosting concept with hot gas supply, condensation and expansion is well known from traditional refrigerants.
Det nye ved det beskrevne princip er, at afrimning sker med komprimeret C02rjsamt at 20 antallet af komponenter, der skal udlægges til højt tryk med den valgte udformning af systemet, minimeres, idet det kun er rørstrækket på kompressorens 7 trykside (7)-(1)-(2)-(3), fordamperen og rør mellem 8 og 9, der skal lægge ud for kondensenngs-/afrimmngstrykket, for eksempel 60 bar, mens resten af anlægget kan dimensioneres til for eksempel 25 bar, herunder pumpebeholderen 10 25The new principle described is that defrosting is done with compressed CO 2, and that the number of components to be applied to high pressure with the chosen design of the system is minimized, since it is only the pipe tension on the pressure side of the compressor 7 (7) - (1 ) - (2) - (3), the evaporator and pipes between 8 and 9 to apply the condensation / defrost pressure, for example 60 bar, while the rest of the system can be dimensioned to for example 25 bar, including the pump container 10 25
Systemet er vist i detaljer i figur 1 og 2, hvor der kun er vist tilslutning til en enkelt fordamper 44, men unitten 30 kan principielt tilsluttes et vilkårligt antal fordampere 44, der skiftevis afrimes efter behov 30 Normalt vil der under afrimning af en fordamper være belastning på pumpebeholderen 10 fra de øvrige fordampere Hvis der kun er en fordamperumt på C02 siden, vil det være nødvendigt at tilføre C02 beholderen en ydre belastning, eksempelvis ved at til- 10 DK 174257 B1 føre varm gas fra hovedkompressoranlæggets højtryksside, trykssiden af lav tryksidens kompressor, varm glykol eller elvarme gennem en ydre spiral 15 på C02 beholderen 10 eller receiveren 211 figur 3 5 Efter endt afrimning stoppes kompressoren 7, og ventilen 1 lukkesThe system is shown in detail in Figures 1 and 2, where only a single evaporator 44 is shown, but the unit 30 can in principle be connected to any number of evaporators 44 which are alternately defrosted as needed 30 Normally during defrosting of an evaporator there will be load on the pump container 10 from the other evaporators If there is only one evaporator space on the CO2 side, it will be necessary to apply an external load to the CO2 container, for example by supplying hot gas from the high pressure side of the main compressor system, the pressure side of the low pressure side. compressor, hot glycol or electric heat through an outer coil 15 on the CO2 container 10 or the receiver 211 Figure 3 5 After defrosting, the compressor 7 is stopped and the valve 1 is closed.
Unitten kan tilsluttes enhver anlægsudformning, hvor der anvendes C02 Som vist skematisk i figur 4 skal den nye unit 30 blot tilsluttes med en sugeledmng 31 på gassiden af det eksisterende anlægs fordelingssystem samt en retur ledning 33 10The unit can be connected to any system design using C02 As shown schematically in Figure 4, the new unit 30 must simply be connected with a suction line 31 on the gas side of the existing system distribution system and a return line 33 10
Fordehngssystemet 40 kan enten være med direkte fremføring af væske til fordampere (direkte ekspansion), og i dette tilfælde kan sugeledmngen 31 tilsluttes enten på receiveren 21 eller på C02 kompressorens 22 sugeside I andre tilfælde består fordelingssystemet af en pumpebeholder 10, hvorpå sugeledningen 31 kan tilsluttes 15The displacement system 40 can be either directly fed with liquid to evaporators (direct expansion) and in this case the suction line 31 can be connected either to the receiver 21 or to the suction side of the CO 2 compressor 22. In other cases, the distribution system consists of a pump container 10 to which the suction line 31 can be connected. 15
Fra den nye unit skal der føres en varm gasledning 32 (f eks 60 bar) til de enkelt fordampere 44, som skal afrimes I den beskrevne opfindelse vil trykket (f eks -5°C mætmngstemperatur) altid være 20 lavere end mætningstrykket ved omgivelsernes temperatur Kompressoren 7 anvendes i dette tilfælde til altid at holde trykket under et givet setpunkt (f eks -5°C) Ventilen 1 lukkes og 2 åbnes Trykgassen føres i dette tilfælde i stedet igennem en varmeveksler 4, hvor den afleverer energi til omgivelserne eller et andet varmedræn og derfra ekspanderes den tilbage i C02 beholderen 10 gennem ekspansionsventilen 5 25From the new unit, a hot gas line 32 (e.g. 60 bar) must be fed to the single evaporators 44 to be defrosted. In the described invention, the pressure (e.g. -5 ° C saturation temperature) will always be 20 lower than the saturation pressure at ambient temperature. In this case, the compressor 7 is used to always keep the pressure below a given set point (eg -5 ° C). The valve 1 is closed and 2 is opened. In this case the pressure gas is instead passed through a heat exchanger 4, where it delivers energy to the environment or another heat drain and from there it is expanded back into the CO 2 container 10 through the expansion valve 5 25
Ved lav omgivelsestemperatur (for eksempel mindre end 20°C) er der tale om en traditionel dampkompressionproces, men for at kunne varetage opgaven uafhængig af årstid, geografiske forhold og kondensatortype, skal processen kunne køre trans-knstisk (over 31°C, hvor kondensering ikke længere finder sted)At a low ambient temperature (for example, less than 20 ° C), it is a traditional vapor compression process, but in order to carry out the task regardless of the season, geographical conditions and type of condenser, the process must be able to run trans-cstically (above 31 ° C, where condensation no longer takes place)
Kompressoren styres on/off af pressostaten 6 i forhold til setpunktet Hele anlægssiden med C02 holdes ved trykket givet ved pressostatens setpunkt dog med undtagelse af 30 11 DK 174257 B1 fordamperen, som er ved omgivelsestemperatur Fordamperen holdes under stilstand i ligevægt med omgivelsestemperaturen ved at ekspandere væske fra fordamperen gennem hoved ventilen 9, indtil fordamperen er tømt for væske Trykket i fordamperen svarer da også til pressostatens setpunkt 5The compressor is controlled on / off by the pressure switch 6 in relation to the set point The entire plant side with CO 2 is kept at the pressure given at the set point of the pressure switch, with the exception of the evaporator, which is at ambient temperature. The evaporator is kept at a standstill in equilibrium with the ambient temperature by expanding liquid. from the evaporator through the main valve 9 until the evaporator is emptied of liquid The pressure in the evaporator then corresponds to the set point of the pressure switch 5
Det nødvendige energiforbrug til at varetage trykbegrænsningen vil normalt være minimal sammenlignet med kapaciteten afkølesystemetThe energy consumption needed to meet the pressure limitation will usually be minimal compared to the cooling system capacity.
Claims (11)
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DK200100310A DK174257B1 (en) | 2001-02-23 | 2001-02-23 | Installations and methods where CO2 is used as a refrigerant and as a working medium for defrosting |
| PCT/DK2002/000121 WO2002066908A1 (en) | 2001-02-23 | 2002-02-25 | System and method in which co2 is used for defrost and as refrigerant during stand-still |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DK200100310 | 2001-02-23 | ||
| DK200100310A DK174257B1 (en) | 2001-02-23 | 2001-02-23 | Installations and methods where CO2 is used as a refrigerant and as a working medium for defrosting |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| DK200100310A DK200100310A (en) | 2001-06-06 |
| DK174257B1 true DK174257B1 (en) | 2002-10-21 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DK200100310A DK174257B1 (en) | 2001-02-23 | 2001-02-23 | Installations and methods where CO2 is used as a refrigerant and as a working medium for defrosting |
Country Status (2)
| Country | Link |
|---|---|
| DK (1) | DK174257B1 (en) |
| WO (1) | WO2002066908A1 (en) |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DK1409936T3 (en) * | 2001-06-13 | 2007-04-23 | York Refrigeration Aps | Defrosting of cascade cooling systems using CO2 hot gas |
| US6588221B1 (en) * | 2002-10-23 | 2003-07-08 | Super S.E.E.R Systems Inc. | Refrigeration system with dedicated compressor for hot gas defrost |
| DE10332859A1 (en) * | 2003-07-18 | 2005-02-10 | Linde Kältetechnik GmbH & Co. KG | Hot gas defrosting for refrigeration systems |
| CA2602536C (en) * | 2004-09-30 | 2012-09-18 | Mayekawa Mfg. Co., Ltd. | Ammonia/co2 refrigeration system |
| WO2008112549A2 (en) * | 2007-03-09 | 2008-09-18 | Johnson Controls Technology Company | Heat exchanger |
| CA2760488A1 (en) * | 2008-04-18 | 2009-10-18 | Serge Dube | Co2 refrigeration unit |
| US8789380B2 (en) * | 2009-07-20 | 2014-07-29 | Systemes Lmp Inc. | Defrost system and method for a subcritical cascade R-744 refrigeration system |
| US9194615B2 (en) | 2013-04-05 | 2015-11-24 | Marc-Andre Lesmerises | CO2 cooling system and method for operating same |
| CA2928553C (en) | 2015-04-29 | 2023-09-26 | Marc-Andre Lesmerises | Co2 cooling system and method for operating same |
| EP4305362A1 (en) * | 2021-03-09 | 2024-01-17 | Lowenco A/S | A cold storage, a method of operating a cold storage, and a cooling system |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3675441A (en) * | 1970-11-19 | 1972-07-11 | Clark Equipment Co | Two stage refrigeration plant having a plurality of first stage refrigeration systems |
| GB2258298B (en) * | 1991-07-31 | 1995-05-17 | Star Refrigeration | Cooling method and apparatus |
| DE4340689C1 (en) * | 1993-11-30 | 1995-01-12 | Buse Gase Gmbh & Co | Method for cooling gases |
| EP1134514A1 (en) * | 2000-03-17 | 2001-09-19 | Société des Produits Nestlé S.A. | Refrigeration system |
-
2001
- 2001-02-23 DK DK200100310A patent/DK174257B1/en not_active IP Right Cessation
-
2002
- 2002-02-25 WO PCT/DK2002/000121 patent/WO2002066908A1/en not_active Ceased
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| Publication number | Publication date |
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| DK200100310A (en) | 2001-06-06 |
| WO2002066908A1 (en) | 2002-08-29 |
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