Odp is ozone depletion potential of with re ference to cfc r11 as 1. Choice of refrigerants for ship refrigeration systems. For the benefit of our customers, we combine leading industry knowledge. Types of refrigerants and their environmental impact. Ahris research arm, the airconditioning, heating, and refrigeration technology. Global warming potential gwp is a relative measure of how much heat a refrigerant traps in the atmosphere. Fellow ashrae mcquay international staunton, virginia usa 1 what is a refrigerant.
Our natural refrigerants provide zero ozone depletion potential odp and minimal. Global warming potential vs ozone depletion potential. The process is not easy, and although there are alternatives to old refrigerants, the new ones are usually not. Global warming potential of various refrigerants 18 table 6. Companies like honeywell are to looking into redesigning appliances like air conditioners and refrigerant applications that have a lower gwp. Refrigerant retrofits unit 9 test flashcards quizlet. R427a like other gases such as r407c is a zeotrope. Which refrigerants have the lowest ozone depletion potential. Originally the title given was new and alternative refrigerants but i.
W ith the ratification of the montreal protocol in 1987, chlorofluorocarbon cfc and hydrochlorofluorocarbon hcfc refrigerants, such as r11, r12, r22, and r123, have been or will soon be phased out due to their high ozone depleting potential odp. Desirable properties of refrigerants chemical engineering site. Historically, chlorofluorocarbons cfcs were used extensively as refrigerants in the air conditioning and refrigeration industries. Refrigerants and their environmental impact substitution of. Even though hfcs have a zeroodp, in some cases it has a global warming potential highgwp. Linde strongly advocates the use of refrigerant gases with zero ozone depletion potential and fully supports the phase out of hcfcs. A comparative study on the environmental impact of co2 supermarket refrigeration systems. In most cases no timeconsuming circuit rinsing is required. In general, all refrigerants are characterised by two numbers. Currently the major refrigerant is switching to hydrofluorocarbons hfcs which has zero ozone depletion potential zeroodp. This continues to this day and at this juncture, just after the adjustment of the montreal protocol to achieve an early phase out of hcfcs, the last major group of ozone depleting substances with high global warming potential, we might miss another opportunity unless we are watchful. For each ods, this page provides the compounds atmospheric lifetime, ozone depletion potential ozone depletion potentiala number that refers to the amount of ozone depletion caused by a substance.
Ozone depletion potential odp there are also some chemical compounds, which include refrigerants, that contribute to the depletion of the ozone layer. Refrigerant types, issues, trends and future options. Human activities are the main reason for its depletion. It has a high chlorine content and ozone depletion potential odp, and high global warming potential.
The formula for rll is ccf and it has the chemical name trichloromonofluoromethane. Limited options for lowglobalwarmingpotential refrigerants. Hydrocarbons are a very limited solution to the environmental. Odp is expressed as a relative potential of ozone depletion compared to influence of r11 which has odp1. Forane 404a r404a is a nonozone depleting, near azeotropic blend of hfc refrigerants r125, r143a, and r4a, and is formulated to match the properties of r502, making it useful for a variety of medium and low temperature refrigeration applications.
Odp is the ozone depletion potential of the substitute, relative to a value of 1. Hfc4a is nonflammable and has zero ozone depletion potential but serious gwp. Global warming potential measurement of global warming done in relation with co2,where co2 has gwp 1 lower the value of gwp better the refrigerant few examples are given below. Cfcs have a particularly high ozone depleting potential odp and while. Environmental impact of the refrigeration and air conditioning sectors refrigerants refrigerants pose a threat to the environment because of their ozone depletion potential odp and global warming potential gwp. What you need to know about the hfc refrigerant phaseout. Gwp global warming potential degree to which a greenhouse gas ghg traps heat in the atmosphere. This article has been excerpted from a comprehensive white paper, refrigerants for commercial refrigeration applications, issued by copeland corp. Products that normally contain ozone depleting substances should be replaced with functionally similar products that contain nonozone depleting substances. Past, present and future perspectives of refrigerants in airconditioning applications 28 rehva journal december 20 articles. The higher the gwp value, the more that particular gas warms the earth compared to carbon dioxide. Chlorodifluoromethane r22, for example, has an odp of 0.
The earliest mechanical refrigeration used air as a working fluid. Nonozone depleting substances ods do not deplete the earths protective ozone layer. A refrigerant is a fluid that is used for heat transfer in a cooling system. Commonly used refrigerants and possible replacements rll is a cfc which is included in the montreal protocol having an ozone depletion potential odp of 1 and a greenhouse potential gp of 3300. The importance of specifying high quality productspdf 765. Guiding you through todays and tomorrows refrigerants and technologies, with emphasis on global warming potential, energy consumption. The less the value of the odp, the better the refrigerant is for the ozone layer, and therefore the environment. Pdf refrigerant types, issues, trends and future options.
Table 1 gives an overview of the different groups of refrigerants. Energy procedia 18 2012 807 a 816 18766102 a 2012 published by elsevier ltd. Low gwp refrigerant ozonedepletion potential zeroodp. Epa approves three alternative refrigerants to replace hfcs. The odp of chemicals is the measure of how much it causes the ozone layer to degrade as compared to trichlorofluoromethane cfc11, which has a baseline odp of 1. Global warming potential gwp is a measure of how much a given mass of a gas contributes to global. Furthermore, natural refrigerants stand out not only by being environmentfriendly the global warming potential of ammonia is zero and that of carbon dioxide and hydrocarbons is negligibly small but above all by being energy efficient. For some background on ozone and depletion visit the site of the.
They also have good energy efficiency, but are flammable and can form an explosive mixture with air if a leak occurs. Cfcs are generally characterised by a big odp value, because they contain chlorine, which is accused of heavily contributing to the. The paper gives results of tests of 2 of 11 compounds and several mixtures selected for intensive evaluation from about 40 new synthesized compounds that may serve as environmentally safe and effective refrigerant alternatives over the long term. The ozone depletion potential odp of a refrigerant is the relative amount of depletion to the ozone layer it can cause.
Apr 12, 2020 the ozone depletion potential odp of a refrigerant is the relative amount of depletion to the ozone layer it can cause. It has long been used in a variety of airconditioning and refrigeration applications in a variety of. Ozone depletion potential odp and global warming potential gwp. Ozone depletion potential odp of a chemical compound is the relative amount of degradation it can cause to the ozone layer. Halogenated hydrocarbons, especially chlorofluorocarbons cfcs, are a major cause of ozone layer depletion because of the amounts of chlorine atoms that are part of their makeup. The less the value of the odp the better the refrigerant is for the ozone layer and the environment. According to the montreal protocol, the odp of refrigerants should be zero, i. R218 is an example of a fluorocarbon, and fcs are also present in the mixtures r403 and r408.
Refrigerants can thus also be ranked according to their impact on the stratospheric ozone layer the ozone depletion potential, odp or as greenhouse gases the global warming potential, gwp. Chapter 6 introduction to refrigerants flashcards quizlet. It was designed to provide benefits in efficiency and system size by increasing system pressure and. R11 high chlorine content gwp is 4000 r22 low chlorine content gwp is 1700 r4a no chlorine content gwp is 0 34. Refrigerants typically used in commercial equipment r11, r12, r1 are the worst offenders and the refrigerant used in home air conditioners r22 is a relatively minor offender. Which type of refrigerant has the highest ozone depletion. Stratospheric ozone depletion and hvac refrigerants. Hydrofluorocarbons, currently used as refrigerants in airconditioning systems, are potent greenhouse gases, and their contribution to climate change is. Ozone depletion potential of different refrigerants. Characteristics of some new generation refrigerants with. Zero ozone depletion potential replacement for r22. Add r427a, with an initial charge of 95% of the original weight. Ozone depletion potential refers to the potential at which the ozone is depleting. Cfc 11, or r11 has the maximum potential amongst chlorocarbons because of the.
Way back in the stone age, people knew that food could be kept for longer in the cold, and stored meat and fruit in cool caves protected from heat and the sun. It is a better alternative to r404a in both low and mediumtemperature supermarket applications since it has a higher capacity and efficiency than r404a. R410a is a non ozone depleting binary blend of two hfc refrigerants, comprising 50% of r32 and 50% of r125 by percentage of weight, it has no chlorine content, and only a modest global warming potential. All of the refrigerants use r11 as a calibration and thus r11 has an odp of 1. Comparison of characteristics of some refrigerants 17 table 5. Dichlorodifluoromethane r12 is a colorless gas usually sold under the brand name freon12, and a chlorofluorocarbon halomethane cfc used as a refrigerant and aerosol spray propellant. All of the refrigerants use r11 as a datum reference, and thus r11 has an odp of 1. The conventional cooling systems use refrigerants with high ozone depletion potential odp and greenhouse gas ghg impact and as a consequence the prohibition of hydrochlorofluorocarbons hcfcs. R404a is a ternary refrigerant blend consisting of the hfc r125 fortyfour percent, hfc r143a fiftytwo percent, and hfc r4a four percent. The ozone depletion potential odp of a chemical compound is the relative amount of degradation to the ozone layer it can cause, with trichlorofluoromethane. The search for refrigerants with low global warming potential gwp to replace more harmful hfcs is continuing. Dec 15, 2011 prodded by companies as diverse as ben and jerrys, general electric, a. That first generation of alternative refrigerants included hfcs hydrofluorocarbons, which had no ozone depletion potential. Mar 03, 2015 what refrigerant has the lowest ozone depletion.
Refrigerants can thus also be ranked according to their impact on the stratospheric ozone layer the ozone depletion potential, odp or as greenhouse gases. Restrictions the montreal protocol on substances that deplete the. Ozonedepleting potential of some substances 14 table 4. Gwp is the 100year integrated global warming potential of a chemical or the weighted average of the gwps of the chemicals in a blend, relative to a value of 1 for co. Alternatives to ozone depleting refrigerants in test equipment.
The refrigerant impacts on the environment are evaluated with the ozone depletion potential odp and the global warming potential gwp. And the phaseout of cfc refrigerants under the montreal protocol has helped the antarctic ozone layer to begin to recover. But hfcs are potent greenhouse gases with high global warming potential gwp and long lifetimes. Ozone depletion potential odp a numerical value assigned to refrigerants to compare the destructive potential each refrigerant poses to the ozone layer compared to r11, which has an odp of 1. Linde gas is a global leader in refrigerant solutions and services. In the early 1970s, it was discovered that cfc and hcfc refrigerants breakdown the ozone layer. 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. This refrigeration playbook provides guidance to refrigeration system design teams about selecting energyefficient refrigeration systems that use lowglobal warming potential gwp refrigerants. Refrigerants are divided into groups according to their chemical composition. Refrigerants having nonzero odp have either already been phasedout e. The odp, or ozone depletion potential, is the potential for a single molecule of the refrigerant to destroy the ozone layer. Refrigerants containing chlorine or bromine contribute to the breakdown of the ozone layer see figure 5. Ozone depletion potential odp of a chemical compound is the relative amount of degradation it can cause to the ozone layerglobal warming potential gwp is a measure of how much a given mass of a gas contributes to global warming. A novel modular tool for life cycle climate performance lccp based.
Summary of substitute refrigerants listed in snap notice 25. Refrigeration systems using low global warming potential refrigerants beshr et al. Environmental consciousness refrigerant options now and in the future. Linde strongly advocates the use of refrigerant gases with zero ozone depletion. R717 ammonia linde industrial gases spain linde gas espana. Department of energys commercial building partnerships cbp. The article focuses on the criteria for refrigerant selection, including discussion of the transitional refrigerants hcfcs, chlorinefree refrigerants hfcs, and halogenfree. R12 cfc refrigerants retrofit to hfc r4a with insignificant. Refrigerants and their application presented by thomas e. While analyses and system performance tools have shown that hfc refrigerant blends offer certain performance, capacity. Estimates of relative potentials to enhance global warming halocarbons global warming potential or hgwp will be discussed in a subsequent publication fisher et al.
Odp ozone depletion potential degree to which a substance can degrade the ozone layer. The ozone depletion potential odp of a chemical compound is the relative amount of degradation to the ozone layer it can cause, with trichlorofluoromethane r11 or cfc11 being fixed at an odp of 1. Investigation into the fractionation of refrigerant blends. R404a began seeing usage in 1996 after the phase out of cfc r502 due to its ozone depletion potential. Which of the following refrigerants is a cfctype refrigerant. Alternative refrigerants to cfc12, are hfc152a, hfc4a, mp6639, hc290600a etc. Purpose the purpose of this subarticle is to reduce emissions of high global warming potential refrigerants from stationary, nonresidential refrigeration equipment and from the installation and servicing of refrigeration and airconditioning appliances using highgwp refrigerants. Compared to halogenated refrigerants, hydrocarbons like isobutane r600a and propane r290 offer several advantages. Ahrti flammable refrigerants research initiative the hvacr industry is transitioning to the use of lower global warming potential gwp refrigerants due to environmental and regulatory concerns. Up to two points are awarded where it is demonstrated that hvac refrigerants in use have an ozone depletion potential odp of zero or where no refrigerants are used, as follows. The global warming potential gwp is the relative measure of the. Nextgeneration low global warming potential refrigerants. Product information sorted by product type and name type product r number odp1 gwp2 cfc 12 1 high 10900 high 502 0,33 high 4657 high.
However, they are extremely stable, and they have a high gwp cf. Development of synthetic refrigerants continued in the 1950s, when partially chlorinated refrigerants hydrochlorofluorocarbons or hcfc were introduced, including r22. Common refrigerants and their ozone depletion potential odp and global warming potential gwp are indicated below. Ozonedepleting substances ozone layer protection us epa. The current generation of refrigerants, hydrofluorocarbons hfcs, have zero ozone depletion potential. Systems with natural refrigerants need around 30% less energy. Genetron performax lt refrigerant refrigerants americas.
Computer models have long been used to estimate the relative effects of trace gases on stratospheric ozone. Refrigerants and cfcs a major cause of ozone layer depletion. Gwp values for ozone depleting substances can range, for. R404a has been approved by many refrigeration compressor and system manufacturers for.
R12 cfc refrigerants retrofit to hfc r4a with insignificant ozone depletion potential. Unlike the synthetic hydrocarbon hfc refrigerants that have commonly been used in refrigeration applications such as r404a, r507a and hfc4a ammonia nh 3 or refrigerant name r717, propane refrigerant name r290 and carbon dioxide co 2 or refrigerant name r744 are three naturally occurring refrigerants that pose very little. On a worldwide basis, the most widely used hcfc refrigerant is r22 which has a low ozone depletion potential 5. The odp is the ratio of the impact on ozone of a chemical compared to the impact of a similar mass of cfc11. Honeywell has been granted a patent covering genetron. Next generation refrigeration lubricants for low global. Refrigerants are regulated as hazardous materials by the us epa and carb, due to their ozone depleting ability and powerful greenhouse gas potential. Following the discovery that some of these chemical compounds may be harmful to the environment, they are being replaced with more environmentally friendly alternatives see figure 5. Candidate alternatives for r22 are being evaluated by a consortium of manufacturers in a project called. They have zero ozone depletion potential and a greenhouse warming potential approaching zero. Epa regulations and international treaties prescribe a time table to phase out these.
Indicators for quantitative comparison of the various substancesareodp8ozonedepletionpotentialandgwp9 global warming potential, which are closely related to their atmospheric lifetime alt 10. The initiatives identified in this report are navigants recommendations to bto for pursuing in an effort to accelerate the widespread adoption of lowglobal warming potential gwp refrigerants in residential and commercial equipment. Chlorine interacts with ozone, converting it into oxygen and taking away its beneficial properties. Refrigerant product information opteon xp10 r5a is a nonozone depleting, low global warming potential gwp hydrofluoroolefin hfo based refrigerant developed to replace r4a in positive displacement, direct expansion, mediumtemperature commercial and industrial chillers, as well as flooded andor centrifugal chillers.
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