Refrigerant grade anhydrous ammonia is a clear, colorless liquid or gas, free from visible impurities. Because of ammonia s vaporization properties, it is a useful refrigerant. Ammonia is renowned for its favorable thermodynamic properties. Liquid refrigerant passes through expansion valve a.
It was commonly used before the popularisation of chlorofluorocarbons freons. Ammonia data book a may 2008 appendix a thermodynamic property tables. Retreived from foia by garden city ammonia program on 11. Many of these requirements are identified in this etool as possible controls and are useful as recommended practices whether or not the ammonia refrigeration system is a covered process. Of all known refrigerants, ammonia requires the lowest primary energy input to create a given refrigerating capacity, thanks to its excellent thermodynamic properties. Pdf calculation of properties of nh3h2o refrigerant, and. Pdf on jan 1, 2016, gyula kramer and others published calculation of properties of nh3 h2o refrigerant, and modeling of absorption refrigeration systems. Anhydrous ammonia is widely used in industrial refrigeration applications and hockey rinks because of its high energy efficiency and low cost. Table a12e properties of superheated refrigerant 4a vapor 959 table ae properties of saturated ammonia liquidvapor. First, ammonia is naturally occurring and therefore environmentally compatible2. It is much less expensive than some other refrigerants. Introdution several refrigeration methods are known.
Ammonia system which correctly addresses all of the above issues peculiar to ammonia as a refrigerant that have heretofore prevented its use at low suction temperatures. Ammonia data book 25 may 2008 chapter 2 properties of ammonia chemical properties of ammonia compatibility ammonia reacts readily with a wide variety of substances. Refrigerants are used as working substances in a refrigeration systems. Refrigerant 717 ammonia properties of saturated liquid and saturated vapor surface tension, temp. Compare different refrigerants and suggest replacements for cfcs and hcfcs 26. Refrigerant r22 properties properties of refrigerant r22 dichlorodifluoromethane saturated liquid and saturated vapor imperial and metric units. Among those, if the heat source is available, the most.
The choice of a refrigerant is determined by its physical properties. Ammonia is a safety classification group b2l refrigerant. The phaseout of cfc refrigerants began a little over 10 years later. Pressure table 963 table a15e properties of superheated ammonia vapor 964. Nist standard reference database 23, refprop thermo dynamic properties of refrigerants and refrigerant mixtures, version 3. R717 ammonia can be used both in absorption and in compression systems. In librh 2 o system water is used as a refrigerant and libr is used as an absorbent, while in nh 3h 2 o system ammonia used as an refrigerant and water is used as an absorbent, which served as standard for comparison in studying and developing new cycles and new absorbent refrigerant pairs. Ammonia nh3 is a wellknown refrigerant, particularly applicable in large, industrial plants where its advantages can be fully utilized without compromising safety. Particles usually result from soldering and welding residue, the reaction between refrigerant and oil, etc. It is hazardous when released in large quantities due to its toxicity. A refrigerant is a working fluid used in the refrigeration cycle of air conditioning systems and heat pumps where in most cases they undergo a repeated phase transition from a liquid to a gas and back again. Refrigerant r4a properties thermodynamic properties of refrigerant r4a. The gas is less dense than air and the liquid is less dense than water at standard conditions.
Table a12 properties of superheated refrigerant 4a vapor 909 table a properties of saturated ammonia liquidvapor. At atmospheric pressure it boils at 33c and is therefore suitable for low temperature work. For thermodynamics and fluid mechanics problems, values of entropy, specific heat energy etc must be known for various fluids and their value can easily be obtained from these tables. For those using the thermodynamic properties for ammonia refrigeration cycle analysis, appendix b contains a. Properties of superheated refrigerant 4a vapor 945. Ammonia has a number of characteristics which make it the ideal refrigerant for refrigeration and air conditioning purposes. Ammonia, dichloroflouromethane refrigerant 12 and tetraflouroethane refrigerant 4a. Ammonia density is lower than r404a and co2 which implies an higher compressor swept volume 4, but ammonia has a higher. Separate equations of state for liquid and gas phases are provided for pure ammonia and pure water. Tablet of the propertie of aqua ammonia solutiont by burgess h. However, the oil in the refrigeration system is a contaminant that lowers the efficiency of the. Ammonia, from a chemical standpoint, is a moderately strong base caustic alkali, depending upon its concentration.
Calculate online thermodynamic and transport properties of ammmonia based on industrial formulation formulated in helmholtz energy for advanced technical applications. The most important physical properties of anhydrous ammonia. Has excellent heat transfer and pressure drop performance, both in condensation and vaporisation. Temperature drops to saturated suction temperature c.
Liquid refrigerant from condenser return gas to compressor 70% liquid 30% vapor mix 1. Pressure table 9 table a15 properties of superheated ammonia vapor 914. This code is for the use and guidance of everyone concerned with vapour compression refrigerating systems that use refrigerant r. R143a, r152a, r717 ammonia, and r744 carbon dioxide and refrigerant blends r404a, r 407c, r410a, and r507 conform to isodis draft standard 17584, refrigerant. Ammonia refrigeration systems with 10,000 pounds or more of ammonia are a covered process subject to the requirements of the process safety management standard 29 cfr 1910. In todays world, other properties of the refrigerant are more important. Specific volume v, specific internal energy u, enthalpy h, and entropy s of saturated and superheated ammonia nh 3 also known as refrigerant 717. A refrigeration compressor contains highly loaded mechanical contacts that have to be lubricated.
Both work without difficultly available databases and expensive programs background. Ammonia nh 3 thermodynamic properties engineering toolbox. The drawbacks of ammonia as refrigerant are toxicity to humans and aquatic life an ammonia release indoors can result in an explosion ammonia corrodes certain metals. List important thermodynamic and environmental properties influencing refrigerant selection 5. Fortunately ammonia has been very thoroughly studied by thermodynamicists over the years and. A wellknown and acknowledged refrigerant which has. Refrigerants and specialities wernervonsiemens str 18 d97076 wuerzburg.
Ammonia is environmentally benign, having zero gwp and zero odp. Introduction r717 is refrigerant grade high purity ammonia nh 3. Ammonia is an important commercial fluid which ranks among the top ten bulk chemicals in terms of largescale production. The properties of some of the common refrigerants in use are given below. Pdf on jan 1, 2016, gyula kramer and others published calculation of properties of nh3h2o refrigerant, and modeling of absorption refrigeration systems. Ammonia is incompatible with copper, zinc, or copperbased alloys, and corrosion of these metals will occur.
Ammonia gas compressibility factor z the ratio of the actual volume of the gas to the volume determined according to the perfect gas law 1. Reference states used for most refr igerants correspo nd to the inter. Industrial refrigeration systems using ammonia as a refrigerant are being used since long in many food and process industry installations in india and are growing significantly over the years due to environment friendly properties of ammonia. Ammonia is also an ideal refrigerant from a climate protection point of view, as it contributes neither to ozone depletion nor to global warming. Comparison r404a vs ammonia for cold room design basis3 rooms, each 12mx24mx9msotage 500 ton each temperature 200 c, for storage of frozen products, refrigeration load 3x42kw126kw r404aair cooled r717 ammonia water cooled 2units per room screw compressors6nos. Table a1 molar mass, gas constant, and criticalpoint properties table a2 idealgas specific heats of various common gases table a3 properties of common liquids, solids, and foods table a4 saturated watertemperature table table a5 saturated waterpressure table table a6 superheated water table a7 compressed liquid water table a8 saturated icewater vapor. Refrigerants color codes refrigerants and their color codes. Many of these requirements are identified in this etool as possible controls and are useful as recommended practices. Ammonia, which is a class 2l material, has been used in large industrial refrigeration systems for over 100 years. Ammonia offers three distinct advantages over other commonly used industrial refrigerants. Feb 01, 2017 ammonia is an efficient and popular refrigerant due to its superior thermodynamic properties and low cost. Table a2 superheated vapor properties of ammonia ip units continued saturation t 100 f, p 212.
Pdf refrigerant types, issues, trends and future options. It has remained the main refrigerant used in industrial refrigeration systems because of its superior thermodynamic properties and low cost. In a wide range of applications, it outperforms synthetic refrigerants. Linde has been a leading supplier of refrigerants for over 40 years. An equation of state for ammonia water mixtures is presented. However, there are apprehensions and misconceptions due to toxic nature of ammonia. The introduction of ammonia as a refrigerant was one of the milestone events in history of refrigerants. Theashraeposition documenton ammonia as a refrigerant wasdevelopedbythesocietys refrigeration committee.
It is now possible to successfully apply dx ammonia at suction temperatures down to r50 degrees f. Water may enter the system as a result of installation, service, leakage, etc acid is formed as a result of the breakdown of the refrigerant and oil. Due to much less challenging physical properties, ammonia and halocarbon freon refrigerants dominated, and by the 1960s, almost no co 2 refrigeration systems remained. However, hfcs still dominate the market outright and natural refrigerants, despite their superior properties, still. Kessler, senior process safety engineer introduction. However, ammonia does exhibit a unique refrigerant characteristic due to its irritating odor. Shannon2 these tables of aqua ammonia make available com plete and accessible tabulations, in the english lan guage and in customary engineering units, of the proper ties of aqua ammonia solutions. Institute of refrigeration safety code of practice for.
For full table with specific entropy and superheated properties rotate the screen. Refrigerants are heavily regulated due to their toxicity, flammability and their contribution to ozone depletion and climate change. Anhydrous ammonia is the liquid form of pure ammonia gas, technically waterfree, and the substance used universally as an industrial refrigerant. Fluids suitable for refrigeration purposes can be classified into primary and secondary refrigerants. In nearly all commonly encountered situations, it exists as either a liquid or a gas. The lubricant used in refrigeration compressors consists of an oil and refrigerant mixture, and the refrigerant concentration can be up to 40 wt%. Properties of superheated refrigerant 4a vapor 909. Ammonia data book a1 may 2008 appendix a thermodynamic property tables general because of ammonia s widespread use as a refrigerant, comprehensive tables of thermodynamic properties are frequently needed by refrigeration engineers. Position document committee formed on july 24, 2012 with eric m. Refrigerant 717 ammonia properties of saturated liquid and saturated vapor. Temperature table 912 table a14 properties of saturated ammonia liquidvapor. Thermal properties of liquid ammonia at saturation pressure.
Temperature table 962 table a14e properties of saturated ammonia liquidvapor. Advantages of r717 3 zero ozone depletion potential 3. Pdf an excel addin for refrigerants properties and its. The thermodynamic efficiency of a refrigeration system depends mainly on. The halocarbon refrigerants, largely chlorofluorocarbon cfc and hydrochlorofluorocarbon hcfc chemicals, began to attain nearmonopoly status. In fact, from the thermodynamic or heatcarrying standpoint, differences among refrigerants with similar boiling points are small. Like other natural refrigerants, ammonia r717 represents no threat to either the ozone layer or the earths climate. Primary refrigerants are those fluids, which are used directly as working fluids, for example in vapour compression and vapour absorption refrigeration systems. Duponttm refrigerants, technical information keywords. In the gas phase, the mixture is assumed to behave as an ideal solution, while in the liquid phase, the gibbs excess energy is used to allow departure from ideal solution behaviour. Pdf thermodynamics properties table suddiyas nawaz. Thermophysical properties of refrigerants t his chapter presents data for thermodynamic and transport properties of refrigerants, arra nged for the occasional user.
You are strongly recommended to obtain a set of these tables or similar, for yourself, before continuing with your study, in order to make sense of their use, in this chapter. Smith, chairman international institute of ammonia refrigeration alexandria, virginia, usa richard royal walmart bentonville, arkansas, usa. The first patent for ammonia compressor was granted to david boyle 1837 1891 in 1872. Ammonia suitable for use as a refrigerant is commonly named r717 in the refrigeration and air conditioning industry. 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. However, the demand for environmentally friendly refrigerants seems likely to ensure that ammonia en. Second, ammonia has superior thermodynamic qualities, as a result ammonia refrigera tion systems use smaller pipe sizes and require less heat transfer area6. The equipment used for removing the heat continuously for maintaining a low temperature in a space is called refrigerator. Write the chemical formula of a refrigerant from its number 6. It suffers from the disadvantage of toxicity, and requiring corrosion resistant components, which restricts its domestic and smallscale use. As a substance which dissolves in water to form hydroxyl ions, it is corrosive and destroys.
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