11/22/2014. (c) DR.A.M.SURENDRA KUMAR

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1 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 1

2 HISTORY A substance capable of absorbing heat from another required substance(space) can be used as Refrigerant. Air was used as refrigerant in olden days in many refrigeration systems because most safest/ cheapest refrigerant First refrigerant used - Ether employed by Perkins - hand operated vapour compression machine Then ethyl chloride( C 2 H 5 Cl) Ammonia Methyl chloride was used for domestic and commercial purpose until Freon's were available. 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 2

3 CLASSIFICATION OF REFRIGERANTS 1. PRIMARY- DIRECTLY TAKE PART IN HEAT INTERACTIONS. Ammonia, Carbon dioxide, Sulphur dioxide, Methyl chloride, Ethyl chloride and Freon group 2. SECONDARY FIRST COOLED BY PRIMARY THEN FOR COOLING PURPOSES. Ice, Brine, solid carbon dioxide 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 3

4 PRIMARY REFRIGERANTS 1.HALOCARBON COMPOUNDS:- Contains one or more halogens, chlorine and bromine Invented & developed by Charles Kettering in 1928 Sold in the market under the name as Freon Genetron Isotron Areton Outstanding merits Applications: Domestic, commercial & Industrial purposes 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 4

5 1. HALOCARBON REFRIGERANTS REFRIGERANT NAME CHEMICAL NAME CHEMICAL FORMULA R-10 CARBON TETRA CHLORIDE CCl 4 R-11 TRICHLORO- MONOFLURO METHANE CCl 3 F R-12 DICHLORODIFLURO-METHANE CCl 2 F 2 R-22 MONOCHLORODIFLURO-METHANE CHClF 2 R-30 METHYLENE CHLORIDE CH 2 Cl 2 R-40 METHYL CHLORIDE CH 3 Cl R-100 ETHYL CHLORIDE CH 3 CH 2 Cl 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 5

6 2. AZEOTROPES The refrigerants belonging to this group consist of mixtures of different substances. These substances cannot be separated into components by distillations Example: R-500 It consists of 73.8 % R % R /22/2014 (c) DR.A.M.SURENDRA KUMAR 6

7 3. HYDROCARBONS- ORGANIC COMPOUNDS REFRIGERANT NAME CHEMICAL NAME CHEMICAL FORMULA R-50 METHANE CH 4 R-170 ETHANE C 2 H 6 R-290 PROPANE C 2 H 8 R-600 BUTANE C 4 H 10 R-601 ISOBUTANE CH(CH 3 ) 3 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 7

8 4. INORGANIC COMPOUNDS REFRIGERANT NAME CHEMICAL NAME CHEMICAL FORMULA R-717 AMMONIA NH 3 R-718 WATER H 2 O R-729 AIR O 2 R-744 CARBON DIOXIDE CO 2 R-764 SULPHUR DIOXIDE SO 2 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 8

9 DESIRABLE PROPERTIES OF AN IDEAL REFIGERANT 1. THERMODYNAMIC PROPERTIES: a. Low boiling point b. Low freezing point c. High saturation temperature d. High latent heat 2. CHEMICAL PROPERTIES a. Non-toxicity b. Non-flammable c. Non-corrosiveness d. Non-irritating & Odorless 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 9

10 3. PHYSICAL PROPERTIES a. Low sp.volume b. Low sp.heat. c. High thermal conductivity d. Low viscosity. e. High electrical insulation. 4. OTHER PROPERTIES a. Ease of leakage location b. Availability & Low cost. c. Ease of handling. d. High C.O.P. e. Low Power consumption/tr f. Low pressure ratio & Pressure difference 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 10

11 C.O.P & KW/TONN REFRIGERENT CARNOT NH 3 CO 2 SO 2 F- 11 F- 12 F- 22 F- 113 C.OP kw/ton (c) DR.A.M.SURENDRA KUMAR 11/22/

12 PROPERTIES & USES OF COMMONLY USED REFRIGERANTS 1. AIR: Properties: a. No cost involved. b. Completely non-toxic. c. Completely safe d. C.O.P = 1.67 [ for operating between temp. of 80 0 C & C] Uses : a. Air is one of the earliest Refrigerants and widely used even as late as world war I where ever a completely non-toxic medium was need. b. Because of low C.O.P, it is used only where operating efficiency is secondary as in air craft refrigeration 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 12

13 2. AMMONIA (NH 3 ) Properties:- a. It is highly toxic b. It has excellent thermal properties. c. It has the highest refrigerating effect/ kg of refrigerant. d. Low volumetric displacement. e. Low cost. 3. METHYL CHLORIDE Properties:- a. It is a colorless liquid sweet, non-irritating odor. b. It has sp. gravity of at atm.pressure. c. It is neither flammable nor toxic. Uses:- It has been used in the past in both in domestic & commercial applications It should never be used with Aluminium 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 13

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16 REFRIGERANTS & APPLICATIONS APPLICATIONS REFRIGERANTS IN USE DOMESTIC REFRIGERATORS R-12 SMALL RETAIL SUPERMARKETS R-12, R-22, R-502 AIR-CONDTIONING R-11, R-12, R-22, R-144, R-502 INDUSTRIAL R-717, R-22, R-502 TRANSPORT R-12, R /22/2014 (c) DR.A.M.SURENDRA KUMAR 16

17 TRADE NAME OF REFRIGERANTS TRADE NAME SYMBOL COMPANY ARCTON IMPERIAL CHEMICALS, ENGLAND FREON F EI DU PONT DE NEMOURS, & COMPANY, U.S.A. GENETRON Genetron GENERAL CHEMICAL DIVISION OF ALLIED CHEMICAL & DIE CORP. U.S.A. ISOTRON PENNSYLVANIA SALT MANUFACTURING COMPANY, U.S.A. MAFRON MAFATAL LAL & SPINNING GROUP, INDIA KALTRON KALI- CHEMI IBERIA SA, SPAIN KORFORN ULSHAL CHEMICALS, KOREA FORONE ATOCHEM,FRANCE REFRON GUJRATFLURO CHEMICAL LTD., INDIA. 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 17

18 COLOUR CODE FOR RERFIGERANTS NAME OF REFRIGERANT COLOUR CODE R-12 WHITE R-22 GREEN R-40 ORANGE R-500 RED R-134a LIGHT SKY BLUE R-717 SILVER R- 764 BLACK 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 18

19 METHODS & EQUIPMENTS FOR DETERMINING REFRIGERANT LEAKS. 1.First leak detection device that can be used for some large leaks is listening for the hiss of the escaping refrigerant. Fig. A. 2. Soap bubbles are practical and simple leak detector. Leaking refrigerant will cause bubbles. Fig.B. 3. The halide leak detector is available for use with acetylene or propane. Gas. It operates on the principle that when the refrigerant is allowed in an open flame in the presence of glowing copper the flame will change the color. 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 19

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22 STORAGE & HANDLING FACILITY The refrigerant should be stored in as small pressure vessel as possible. It should be conveniently handled during transportation & charging. Handling of flammable refrigerants requires extreme precautions. Handling of sulphur dioxide should be done carefully otherwise toxication may kill the persons handling the refrigerant. 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 22

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26 REFRIGERANT PIPING & DESIGN The material used for fluro carbon refrigerant piping is either seamless copper tubing or iron. For ammonia only iron pipes are used. Sizes are given in terms of OD for copper tubing - Normal iron pipe sizes (IPS) for iron pipes. 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 26

27 REFIGERENT NOMENCLATURE The refrigerants of Methane and Ethane series are known by their numbers. To simplify the terminology, a number system was developed Each refrigerant carries a specific number and this number is preceded by the word Refrigerant, R or by manufacturers trade name as Freon or Genetron. All 2 digit numbers are derived from Methane All 3 digit numbers are derived from Ethane base. The last digit gives the number of fluorine atoms in the molecule. The digit next to the last digit equals one more than the number of Hydrogen atoms. Any atoms not accounted for in the Methane or Ethane series are Chlorine. 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 27

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31 LUBRICANTS IN REFRIGERATION SYSTEMS For refrigeration systems, oil must perform certain functions other than minimising friction, such as sealing the gas between the suction & discharge ports, Acting as coolant to transfer heat from the crank case to the compressor shell. Synthetic oils such as alkybenzenes & phosphate esters use for R-22 & R-502. Polyalkaline glycol(pag) & esters are primary lubricants for R-134a. 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 31

32 SECONDARY REFRIGERANTS. Used for large refrigeration plants Water, brines(dissoving salt in water), glycols are used. Used for carrying refrigeration from the plant room to the space where it is usefully applied, instead of directly obtaining it by the evaporating refrigerant at the place of application. To reduce the quantity of refrigerant charge in the system & reduce pressure losses. Desirable properties of secondary Refrigerant : a. Low freezing point b.. Low viscosity. c. Non flammability. d.. Good stability. Example: chilled water is used as secondary refrigerant in A/C plant. For low temperature applications, brines, glycols & hydrocarbons are used. 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 32

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35 OZONE DEPLETION POTENTIAL [ODP] The earth s ozone layer in the upper atmosphere (stratosphere) is needed for absorption of harmful ultraviolet rays from the sun. These rays can cause Cancer. CFC have been linked to the depletion of this ozone layer CCl 2 F 2 SUNLIGHT CClF 2 Cl O 3 Cl SUNLIGHT ClO O 2 They varying degrees of ozone depletion potential (ODP). 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 35

36 ODP & GWP Details are given for the following reference terms with a brief explanation, such as its effect on the Ozone layer and Greenhouse effect. ODP - The ODP or Ozone Depletion Potential, is the potential for a single molecule of the refrigerant to destroy the Ozone Layer. All of the refrigerants use R11 as a datum reference and thus R11 has an ODP of 1.0. The less the value of the ODP the better the refrigerant is for the ozone layer and therefore the environment. GWP - The GWP, or Global Warming Potential, is a measurement of how much effect the given refrigerant will have on Global Warming in relation to Carbon Dioxide, where CO2 has a GWP of 1. This is usually measured over a 100-year period. In this case the lower the value of GWP the better the refrigerant is for the environment 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 36

37 R11 is a single chlorofluorocarbon or CFC compound. It has a high chlorine content and ozone depletion potential (ODP) and high global warming potential (GWP). The use and manufacture of R11 and similar CFC refrigerants is now banned within the European Union even for servicing. - ODP = 1, GWP = 4000 Note: Although the use of R11 is banned, it was used as the datum for ODP therefore having an ODP of 1. The ODP of all other refrigerants are compared to R11 R22 is a single hydrochlorofluorocarbon or HCFC compound. It has low chlorine content and ozone depletion potential and only a modest global warming potential. R22 can still be used in small heat pump systems, but no more new systems can be manufactured for use in the EU after late From 2010 only recycled or saved stocks of R22 can be used, as it will no longer be manufactured. - ODP = 0.05, GWP = 1700 Phase out dates for R22 From 1 July 2002 no more cooling only air conditioning equipment can be manufactured that uses refrigerant R22. refrigerants 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 37

38 R22. From 1 January 2004 no more heat pump equipment can be manufactured that uses refrigerant R22. After 1 January 2010 no more virgin refrigerant R22 can be used in existing systems. After 2015 no more recycled refrigerant R22 can be used in existing systems. If you have recently installed an R22 air conditioning system the phase out dates should not cause you concern. Your system will only require additional refrigerant should a leak or major repair is required and this can be effected within current legislation until There is already a "drop in" replacement refrigerant for R22 with zero ODP - R417A - See below. 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 38

39 R134A is a single hydrofluorocarbon or HFC compound. It has no chlorine content, no ozone depletion potential, and only a modest global warming potential. ODP = 0, GWP = 1300 R407C is a ternary blend of hydrofluorocarbon or HFC compounds, comprising 23% of R32, 25% of R125 and 52% of R134a. It has no chlorine content, no ozone depletion potential, and only a modest direct global warming potential. ODP = 0, GWP = 1610 R410A is a binary blend of hydrofluorocarbon or HFC compounds, comprising 50% of R32 and 50% of R125) it has no chlorine content, no ozone depletion potential, and only a modest global warming potential. ODP = 0, GWP 1890 R417A is the zero ODP replacement for R22 suitable for new equipment and as a drop-in replacement for existing systems. There are currently no restrictions on equipment or use of the following refrigerants: R134A, R407C, R410A, and R417A. 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 39

40 Alternative refrigerants R290 - Pure propane, a hydrocarbon (HC) an efficient naturally occurring refrigerant with similar properties to R22, but has no ozone depletion potential and an extremely low global warming potential. Whilst it is environmentally safe, it is also highly flammable and must only be used after careful consideration is given to safety. - ODP = 0, GWP = 3. Ammonia - A highly efficient refrigerant, that has been used in industrial applications for many years and with success. It is however, highly toxic and very careful consideration must be given to any design or application. 11/22/2014 (c) DR.A.M.SURENDRA KUMAR 40

The Problem of Counterfeit Refrigerants

The Problem of Counterfeit Refrigerants James K Carson President, Commission C2, International Institute of Refrigeration Senior Lecturer, School of Engineering, University of Waikato j.carson@waikato.ac.nz