Production and consumption of ozonedepleting substances. Linde also advocates the use of lower global warming potential gases when they contribute to an overall reduction in the carbon footprint of refrigeration systems. Environmental effects of refrigerants depletion of the ozone layer in the stratosphere global warming. Calculating ozone depleting potentials odp introduction the number of single component refrigerants with different thermodynamic properties suitable for different types of equipment is limited. Natural and synthetic refrigerants, global warming. However, r410a has a high global warming potential of 2088, higher than that of r22.
Beginning the early 80s, cfc refrigerants containing chlorine such as r12 were found to diffuse up into the stratosphere. Nextgeneration low global warming potential refrigerants. Ozone depletion potentials and global warming potentials the effectiveness of bromine compared with chlorine on a peratom basis for global ozone depletion, typically referred to as. Refrigerants are regulated as hazardous materials by the us epa and carb, due to their ozone depleting ability and powerful greenhouse gas potential. All of the refrigerants use r11 as a calibration and thus r11 has an odp of 1. Ozone depletion potential of different refrigerants. One chlorine atom has the potential to destroy more than 100,000 ozone molecules. Refrigerant selection to reduce climate impact edge buildings. Refrigerants were compared within their own groups in terms of liquid density. 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. Widely used refrigerant blend, foam blowing agent, fire suppressant, and. Cfcs class ii substance ozone depleting chemical with an ozone depletion potential. The refrigerant impacts on the environment are evaluated with the ozone depletion potential odp and the global warming potential gwp. Globally, there is a growing interest in ammonia as a refrigerant, both by itself, and in cascade.
Hcfc22 hfc125 propane freon hp80 r402a, wt% 38 60 2 freon hp81 r402b, wt% 60 38 2 in addition, chemours has formulated a mixture based on allhfc refrigerants, which results in no ozone depletion factor. The chlorofluorocarbons also called cfcs are a class of refrigerants containing the halogens chlorine andor fluorine on. Refrigerant product information opteon xp10 r5a is a non ozone 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. The regulation for the management of high global warming potential refrigerants for stationary sources carb. Although hcfc22 production is controlled for refrigerant. Ozone depletion and global warming overview page 1 of 5. Odp is expressed as a relative potential of ozone depletion compared to influence of r11 which has odp1. Refrigerant types, issues, trends and future options. The nextgeneration refrigerants will require essentially zero odp and low global warming potential. Odp defined the odp, or ozone depletion potential, is the potential for a single molecule of the refrigerant to destroy the ozone layer. Odp is ozone depletion potential of with re ference to cfc r11 as 1.
Chlorodifluoromethane r22, for example, has an odp of 0. Examples of ozone depletion and global warming potentials of refrigerants 100 yr values 11. The ozone depletion potential odp is the ratio of the impact on ozone of a chemical compared to the impact of a similar mass of chlorofluorocarbon cfc 11. 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. Alternative refrigerants free download as powerpoint presentation. Ppt ozone layer depletion authorstream presentation. Measurements of chlorine within the antarctic ozone hole from nasas aura satellite. The first generation of refrigerants included substances such as hydrocarbons, ammonia, and carbon dioxide. It represents the potential of an organic solvents vapor to form ozone relative to that of. This is the process of ozone depletion and has already caused a substantial amount of damage to the ozone layer.
Non ozone depleting substances ods do not deplete the earths protective ozone layer. 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. R404a began seeing usage in 1996 after the phase out of cfc r502 due to its ozone depletion potential. The hazard is represented by the refrigerant ozone depletion potential number odp. This reduction has largely been driven by the 1987 united nations environment programme unep montreal protocol. If the refrigerant is less efficient than r4a or r410a, the lower efficiency chiller will contribute more to global warming through higher energy usage, leading to increased carbon emissions. The greatest concentration of ozone are found from 12 km to 50 km above the earth forming a layer in the stratosphere which is called the ozone layer. In particular, property managers must oversee the proper management of refrigerants and refrigerant containing. Research and development roadmap for nextgeneration low global warming potential refrigerants introduction 9 1 introduction 1. Ozone depleting substances refrigerant reclaim australia. 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. Choice of natural refrigerants makes no net addition of the greenhouse gases ghg in the environment. Refrigerants r407c and r407a properties, uses, storage. Limited options for lowglobalwarmingpotential refrigerants.
Ozone depletion and global warming potential of thermal. Common refrigerants and their ozone depletion potential odp and global warming potential gwp are indicated below. Understanding a2l refrigerants for air conditioners 2019. Different substances break down ozone more rapidly than others. On top of that there is the direct ozone depletion potential gwp due to refrigerant emission. The core contains 25 general knowledge questions relating to stratospheric ozone depletion, rules and regulations of the clean air act, the montreal protocol, refrigerant recovery, recycling and reclaiming, recovery devices, substitute refrigerants and oils, recovery techniques, dehydration, recovery cylinders, safety, and shipping. Cfc 11, or r11 has the maximum potential amongst chlorocarbons because of the presence of three chlorine atoms in the molecule. It mandates that all refrigerants with odp will be phased out for new equipment by january 1, 2020. An estimated 90% of vehicles manufactured for sale. R404a is a ternary refrigerant blend consisting of the hfc r125 fortyfour percent, hfc r143a fiftytwo percent, and hfc r4a four percent.
This transition was a global effort under an international treaty known as the montreal protocol mp that addressed the destructive effects these compounds had on the ozone layer. A significant reduction in the consumption of ozone depleting substances ods has been achieved by the eea33 countries since 1986. Although these refrigerants have no ozone depletion potential, they have a negative impact on global warming when these refrigerants leak to atmosphere during system operation. Cfc replacements used as refrigerants, aerosol propellants. The antarctic ozone hole is a dramatic demonstration of the environmental impact caused by emissions of cfcs, hcfcs and other ozone depleting substances ods that release chlorine and bromine as they break down in the stratosphere. Graph showing the ozone depletion potential odp, or potential damage that each substance could cause to the ozone layer, relative to the chlorofluorocarbon, cfc11. Environmental consciousness refrigerant options now and in the future danfoss helps define your refrigerant choice making modern living possible a paper on the global trends within refrigeration and air conditioning. Ozonedepleting substances ozone layer protection us epa. Unlike alkyl halide refrigerants that contain bromine or chlorine, r410a which contains only fluorine does not contribute to ozone depletion and is therefore becoming more widely used, as ozone depleting refrigerants like r22 are phased out. Environmental consciousness refrigerant options now and in. Ozone depletion potential is measured relative to cfc11 and it represents the amount. Report on the treatment by leed of environmental impact of hvac refrigerants leed technical and scientific advisory committee hcfc task group 9282004 page ii table of contents. Natural refrigerants sustainable ozone and climatefriendly alternatives to hcfcs. The low ozone depletion potential of r22 compared to cfc11 chlorofluorocarbon 11 and cfc12 and its excellent refrigerant properties have helped facilitate the transition away from cfcs.
Growing demand for refrigeration and airconditioning with diversified applications has led to a continued search. Oems have reduced their environmental impact by transitioning to refrigerants with lower ozone depletion potential odp and lower global warming potential gwp. Products that normally contain ozone depleting substances should be replaced with functionally similar products that contain non ozone depleting substances. This is measured by their ozone depletion potential odp. A critical link in protecting climate and the ozone layer. The treatment by leed of the environmental impact of hvac.
Hfcs such as r4a used in positive pressure centrifugal chillers have no ozone depletion potential odp. Global warming potential vs ozone depletion potential. The primary disadvantage of r407c is the large temperature glide due to the blend of the specific refrigerants. Table 1 gives an overview of the different groups of refrigerants. Ozone depletion potential an overview sciencedirect topics. Odp is the ratio of ability of a substance to degrade ozone, to that of chlorofluorocarbon11 cfc11, which therefore, has a value of 1. Introduction under the montreal protocol on substances that deplete the ozone layer, article 7 of the protocol requires all parties, both developing countries also called article 5 countries and developed countries.
Restrictions the montreal protocol on substances that deplete the. R1150 is nontoxic, with zero odp ozone depletion potential and very low gwp global warming potential. Examples of ozone depletion and global warming potentials of refrigerants 100yr values 11. Review and quiz terms and acronyms used in this training material class i substance ozone depleting chemical with an ozone depletion potential greater than 0. R1150 is refrigerant grade ethylene ethene, a natural, or not in kind, refrigerant suitable for use in very low temperature refrigeration applications, such as those found in lng liquefaction processes. Under this circumstance, natural refrigerants such as nh3, hc and co 2 are thus obtaining more and more favour because of their very low environmental impact. Pdf refrigerant types, issues, trends and future options. Linde strongly advocates the use of refrigerant gases with zero ozone depletion potential and fully supports the phase out of hcfcs. Since the introduction of the montreal protocol, european consumption eea28 in 1986 has fallen from approximately 343 000 ozone.
In order to reduce the depletion of ozone and reverse the climate change effects, the european union legislation 2014 and paris accord 2016 are strongly emphasizing the phasing out of the use of harmful synthetic refrigerants. Refrigerants r402a, r402b, and r404a properties, uses. Second, because of its superior thermodynamic properties, ammonia as a refrigerant requires less energy than other refrigerants when used in large industrial systems. The odp is the ratio of the impact on ozone of a chemical compared to the impact of a similar mass of cfc11. Refrigerants used in air conditioners are changing again. Refrigerants directly contributing to global warming when released to the atmosphere. 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. The last round of changes took place between the mid1990s through 2010, as cfc and hcfc refrigerants were phased out and largely replaced by hfcs. Boussouf et al ignition of r32 and r410a refrigerant mixtures with lubricating oil. R111, 2 global warming potential 100 year, ipcc 4th assessment report, 2007. In some categories of the leed rating system, minimum energy performance and fundamental refrigerant management are included as a prerequisites, the intent is to establish a minimum level of energy efficiency for the building system and reduce ozone depletion potential, gwp, and support early compliance with epa montreal protocol. This chlorine was the principal cause of destruction of the ozone layer which protects life on earth from excess ultraviolet light. Ozonedepleting potential odp is the ratio of the impact on ozone caused by a chemical. Characteristics of some new generation refrigerants with.
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