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To: BBell

Maybe some pre-1996 refrigerators were thrown away. This stuff was used in millions of tings, so I’m not going to panic. Impressive they can measure the release, though.


2 posted on 05/17/2018 2:30:10 AM PDT by Dr. Sivana (There is no salvation in politics.)
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To: Dr. Sivana
That was my first thought as well.

The halocarbon CFC-11 has extensively been used as a blowing agent for polyurethane (PUR) insulation foams in home appliances and for residential and industrial construction. Release of CFCs is an important factor in the depletion of the ozone layer. For CFC-11 the future atmospheric concentrations will mainly depend on the continued release from PUR foams. Little is known about rates and time frames of the CFC release from foams especially after treatment and disposal of foam containing waste products. The CFC release is mainly controlled by slow diffusion out through the PUR. From the literature and by reevaluation of an old reported experiment, diffusion coefficients in the range of 0.05-1.7 x 10(-14) m2 s-1 were found reflecting differences in foam properties and experimental designs. Laboratory experiments studying the distribution of CFC in the foam and the short-term releases after shredding showed that about 40% of the CFC is solubilized in the PUR phase, and that up to 10% of the total content will be released within a few weeks if the foam is shredded down to 2-cm sized pieces. For smaller pieces the quick release will be larger. Fifty percent of residual CFC content will be released within 9-300 years from 2-cm pieces based on the range in diffusion coefficients reported. For larger pieces the initial release is insignificant, and the release time frames are much longer than for the shredded foam.

6 posted on 05/17/2018 2:44:12 AM PDT by BBell (calm down and eat your sandwiches)
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To: Dr. Sivana

...And maybe the millions of tons of pre-80s styrofoam now currently buried in landfills all around the world, and which was often manufactured using CFCs, and which slowly breaks down over time.


24 posted on 05/17/2018 6:12:10 AM PDT by Kriggerel ("All great truths are hard and bitter, but lies... are sweeter than wild honey" (Ragnar Redbeard))
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