Refrigerant a fluid which, through phase changes from liquid to gas and back to liquid, facilitates heat transfer in a refrigeration system. The two main uses of refrigerants are refrigeratorsfreezers and air conditioners. The first option increases the cost of electricity which is undesirable. Pdf natural and synthetic refrigerants, global warming. Ari was recently acquired by hudson technologies, and will operate as a whollyowned subsidiary. The alternate refrigerants to be used in the project have very less. Refrigerants have much lower boiling points than water and their boiling points can be varied by changing the pressure of the system.
Classification can be divided into class 1, class 2, class 3. Thermodynamic properties of duponttm freonr 22 refrigerant author. Without being pressureregulated, primary refrigerants absorb all available heat. Low boiling point otherwise operation at high vacua becomes a necessity low condensing pressure to avoid. We provide packages from laboratory samples to 15tonne bulk deliveries. Chlorofluorocarbons cfcs, hydrochlorofluorocarbons hcfcs and hydrofluorocarbons hfcs are synthetic substances used as refrigerants.
Boc offers a comprehensive range of natural refrigerants as well as traditional fluorocarbon refrigerants to the refrigeration and air conditioning industry. Designation and safety classification of refrigerants. Here are some of the desirable properties of refrigerant explained in detail. Low boiling point otherwise operation at high vacua becomes a necessity low condensing pressure to avoid heavy machine plant scantling and reduce the leakage risk.
In most cycles it undergoes phase transitions from a liquid to a gas and back again. The refrigerant used should preferably be inexpensive and easily available. The thermochemical and physical properties of each refrigerant were used to determine. Freon refrigerants r11, r12 and r22, plus ammonia and water, will be discussed in terms of the above categories. Whenever we choose them for particular use properties of refrigerants also plays a vital role in economic and environmental friendly application. The conditions include 1 the use of unique fittings, 2 the use of descriptive labels, and. The refrigerants have a thermodynamic property chart on pressureenthalpy coordinates with an abbreviated set of tabular data for saturated liquid and vapor on the faci ng page. The predictions of system behavior and performance are aided by the known thermodynamic and transport properties of the refrigerant.
What is refrigerant and how does it help your air conditioner. After studying this unit, you should be able to learn the different classifications of refrigerants, naming convention for refrigerants, properties of individual refrigerants, and. Following are the desirable properties of a primary refrigerant. Without being pressureregulated, primary refrigerants absorb all available heat from perishable goods until theyre frozen solid. Secondary refrigerants allow the amounts of environmentally harmful primary refrigerants to be minimized and contained in a restricted area.
If youve heard about the r22 refrigerant phase out in favor of r410a refrigerant, you might be especially interested to know more about how. Pdf current and future trends of refrigerants development. As demonstrated in figure 4, the higher the mie, the. Pdf comparison of high temperature heat pumps on 4th. R407cpsltt r407cpsvtt r407c t sl p p r407c t s vp p r407cdsltt r407cdsvtt r407chsltt r407chsvtt r407cssltt r407cssvtt r407ccpsltt r407ccpsvtt r407ccvsltt r407ccvsvtt r407csurftenstt. After studying this unit, you should be able to learn the different classifications of refrigerants, naming convention for refrigerants, properties of.
Safety properties of refrigerants considering flammability and toxicity are defined by. Jul 17, 2017 a refrigerant with a lower boiling point tends to have a better ability to cool. Synthetic and organic refrigerants are classified under two main categories, primary and secondary. Sep 17, 2014 color codes of refrigerants easy recognize gas cylinder different refrigerant has different color coding few examples are given below. R4a is also known as tetrafluoroethane cf3ch2f from the family of hfc refrigerant. Find answers to your refrigerants questions with honeywell refrigerants suite of apps, calculators, and software. The positive properties of new refrigerants are higher critical temperature. Most automotive air conditioning systems except in australia and possibly other countries use r4a as a refrigerant. Refrigerant safety the risks associated with the use of refrigerants in refrigeration and airconditioning equipment can include toxicity, flammability, asphyxiation, and physical hazards. In fact, from the thermodynamic or heatcarrying standpoint, differences among refrigerants with similar boiling points are small.
Mie would allow greater charge sizes to be used for refrigerants with lower 2l burning velocities or for refrigerants that approach the nonflammable limit. Thermophysical properties of refrigerants t his chapter presents data for thermodynamic and transport properties of refrigerants, arra nged for the occasional user. For commercial refrigeration refrigerants americas. Here we show that only a few pure fluids possess the combination of chemical, environmental, thermodynamic, and safety properties necessary. Experimental investigation of an alternate refrigerant for. Assessment reader android epub pdf of natural refrigerants in different applications. Refrigerants are widely used in refrigeration cycle where cooling effect below the. The most promising refrigerants to be used in future are the hfes, hfos and hfcs with lowgwp, natural refrigerants and blends between hcshfcs and hfcshfos refrigerants. Refrigerants with higher boiling points tend to be more efficient and may work well in a smaller machine.
R22 light green r4a light sky blue r404a orange the name label of the gases are given on the cylinder. Genetron properties software genetron performax and solstice n40 supermarket on line calculators pt chart app and refrigeration selection tool app store marketing and advertising guidelines for developers march 2012 4. In terms of its properties, it should be considered a highclass refrigerant. This article describes thermodynamic properties of the refrigerants the ideal refrigerant. Natural refrigerants overview brochure 63895 12 linde gas.
These properties pressure, temperature, volume, density, enthalpy, flammability, the opportunity to mix with vegetable oil, moisture reaction, smell, toxicity, leakage trend, and leak detection. Pdf halogenated hydrocarbons with high ozone depletion potential odp were. Refrigerants are chemicals used for cooling in automobile air. Many working fluids have been used for such purposes. The database provides bibliographic citations and abstracts for publications that may be useful in research and design of airconditioning and refrigeration equipment. Hydrocarbons are called natural refrigerants because they occur in the earths material cycle, e. They were first used as refrigerants in the early 1920s, but replaced by fully and partially halogenated fluorinated hydrocarbons in. Class 1 indicates refrigerants that do not show flame propagation when tested in air at 21c and 101 kpa class 2 indicates refrigerants having a lower flammability limit of more than 0. A set of 16 refrigerants, both natural and synthetic, as an example. It readily absorbs heat from the environment and can provide refrigeration or air conditioning when combined with other components such as compressors and evaporators. The refrigerant in any refrigerator or air conditioner flows continuously through the vapor compression cycle, absorbing the heat in the evaporator and releasing it in the condenser. Because of the similarities between r22, r11, and r12, only r12 is discussed.
Primary refrigerants change states to absorb heat from surrounding areas or substances. The desirable characteristics of ideal refrigerants are. Usually, a fluid, used in a heat pump and refrigeration cycle that can extract heat from another body or substance. Safety properties of refrigerants considering flammability and toxicity are defined by ashrae standard 34 1. Download limit exceeded you have exceeded your daily download allowance. This unit is intended to serve as an introductory guide to the study of refrigerants.
This information is based on values calculated using the nist refprop database mclinden, m. R22 chc1f425 and r11 cc1435f are colorless, nonexplosive, nonpoisonous refrigerants with many properties similar to those of r12. Refrigerant safety significant new alternatives policy. Properties of refrigerants n low boiling point and high latent heat of vaporization n dense vapor n low toxicity n non flammable n low miscibility with oil.
Refrigerants are divided into three groups according to flammability. Limited options for lowglobalwarmingpotential refrigerants nature. Further efforts are being made to design a measuring cell which allows the determination of electrical properties of refrigerantoil mixtures below ambient. Refrigerant is a compound typically found in either a fluid or gaseous state. Toxicity classification of refrigerants is assigned to classes a or b. Class 1 refrigerants used in the standard compression type cooling system. Duponttm refrigerants, technical information keywords. Natural refrigerants r717 ammonia r744 co 2 hydrocarbon refrigerants fluorocarbon refrigerants.
R11, r12, r22, r4a, r744, r718 are least hazardous, while refrigerants belonging to group b3 e. Refrigerants are classified according to their way of absorption or extraction of heat from substances stored in the refrigerator. Measurement of electrical properties of refrigerants and. A refrigerant is a substance or mixture, usually a fluid, used in a heat pump and refrigeration cycle. Airconditioning and refrigeration institute arl is foimed through a merger of two related. For heat pump and refrigeration equipment it is desirable to have. Refrigerants color codes refrigerants and their color codes. R407cpsltt r407cpsvtt r407c t sl p p r407c t s vp p r407cdsltt r407cdsvtt r407chsltt r407chsvtt r407cssltt r407cssvtt r407ccpsltt r407ccpsvtt r407ccvsltt r407ccvsvtt r407csurftenstt r407cwsltt r407cwsvtt.
These physical properties of refrigerants help us select the proper refrigerant for the application as per our requirement. Many different refrigerants have been used in the past and are in use today with good ability to transfer heat from one place to another. Pdf the present work is devoted to the use of a twostage heat pump with 17 mw. Please consult the msds for more comprehensive information. Class a signifies refrigerants for which toxicity has not been identified. A refrigerant is a compound used in a heat cycle that undergoes a phase change from a gas to a liquid and back. Refrigerants properties pdf product data summary and thermodynamic tables. The liquid at the evaporator coil should therefore vapourise easily, otherwise the compressor will have to create too much of vacuum to cause the liquid to vapourise. Refrigerants are substances that can be used in the refrigeration cycle of air conditioning and refrigeration equipment because of their thermodynamic properties.
With the discovery of the damaging effect of cfcs and hcfcs refrigerants to the ozone layer, the hfc family of refrigerant has been widely used as their replacement. Originally the title given was new and alternative refrigerants but i was also asked to. The former and retrofit refrigerants have different properties with respect to the chemical minor 2 hcfc to hfchfo mo to poepve ab to poepve the former and retrofit refrigerants have different properties with respect to the chemical compatibility with the seals. The liquid has to vapourise at the evaporator coil to cause cooling. Air conditioning and refrigeration institute arl is foimed through a merger of two related. R4a is a common refrigerant used in residential refrigerators around the world, and in automobiles. Thermodynamic properties of duponttm freonr 22 refrigerant. The following is a list of refrigerants with their typeprefix, ashrae designated numbers, iupac chemical name, molecular formula, cas registry number blend name, atmospheric lifetime in years, semiempirical ozone depletion potential, net global warming potential over a 100year time horizon, occupational exposure limitpermissible exposure. Pdf properties of refrigerants from cubic equations of state. Apr 12, 2020 refrigerants are widely used in refrigeration cycle where cooling effect below the atmospheric temperatures are needed. A good example of a common refrigerant is ammonia nh3.
Examples of secondary refrigerants include water, air, hydrocarbons, ammonia and carbon dioxide, which are more environmentally benign than traditional refrigerants such as hcfcs. New, natural and alternative refrigerants by dr s f pearson of star refrigeration limited introduction it is an honour to be invited to present this paper despite the rather daunting title. Refrigerants are widely used in refrigeration cycle where cooling effect below the atmospheric temperatures are needed. In todays world, other properties of the refrigerant are more important. Although refrigerants can pose one or more of these risks, system design, engineering controls, and other techniques mitigate this risk for the use of. Mixtures of r12 vapor and air, in all proportions, will not irritate your eyes, nose, throat, or lungs. Desirable properties of refrigerants chemical engineering site. Jul, 2000 a look at properties and fractionation of blended refrigerants. Effects of refrigerant properties on refrigerant performance citeseerx. Mixtures of r12 vapor and air, in all proportions, will not.