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Concept:
Ozone depletion
Depletion of Ozone layer, observed over the two poles is being relieved with the implementation of Montreal Protocol.
How do refrigerants deplete the Ozone layer: "Refrigerant 22 (R-22 or MonoChloroDiFlouroMethane, CHClF2) is one of the most common refrigerants and is used in a wide variety of applications such as refrigeration, aerosol propellants, cleaning solvents, and foaming agents for plastics. This refrigerant is believed to be partially responsible for damaging the earthˇŻs ozone layer and itˇŻs use is being phased out over the next two decades. The ozone layer is a result of sunlight reacting with oxygen to produce a layer in the stratosphere more than 10 km above the earthˇŻs surface. As R-22 refrigerant escapes from an AC system through leaks or is released into the atmosphere by other means, the R-22 molecule containing the chlorine atom (ˇ°monochloroˇ±) rises in the atmosphere. Sunlight breaks down the R-22 molecule to yield a free chlorine radical (Cl-). The free chlorine radical combines with ozone (O3), decomposing it into normal oxygen (O2).
AC refrigerants come in many varieties. R-22 is the most common, however, due to interactions with the ozone layer R-22 is being phased out. Refrigerants manufactured as replacements for R-22 are HFC-134a, R-410a, R-410b to name a few. The new refrigerants do not contain the chlorine atom and are not harmful to the earthˇŻs ozone layer." |