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AIR PRODUCTS FRIDGE RECYCLING FACT SHEET
11th December 2002
Background
Air Products has pioneered the development of cryogenic
condensation technology used in fridge recycling plants
in Europe and beyond - under the brand name CryoCondap®.
Thirteen fridge recycling plants worldwide currently use
this technology.
The technology works by recovering harmful foam blowing
agents (CFCs and VOCs) and inerting the recycling process,
ensuring safe operation where flammable gases and the creation
of dust are involved. For a safe operation, to avoid VOC
and dust explosions, oxygen levels are monitored.
Recycling new and old fridges
Prior to entering the fridge recycling installation, the
refrigerant (CFCs or butane) and oil are removed from the
cooling circuit. The next step is removal of the refrigerant
compressor after which the fridge is ready to enter the
recycling process. During this process the foam in the fridge
is crushed and foam blowing agents are released.
Fridges manufactured before 1995 can contain foam with
two kinds of ozone depleting substances (ODSs) - these are
the chlorofluorocarbons (CFCs) known as R11 and R12. The
need to recover both CFCs makes the process particularly
complex.
New fridges, or those manufactured since 1995, use cyclopentane
as a blowing agent - which is categorised as a VOC - requiring
safe recovery in an inert atmosphere. The cryogenic condensation
technology applied uses liquid nitrogen to recover both
types of emission (CFCs and VOCs) safely and efficiently,
in one single process.
The CryoCondap® solution
Air Products has pioneered the use of cryogenic condensation
technology to recover harmful emissions during fridge recycling.
The technology, which is known as CryoCondap®, involves
the use of liquid nitrogen and adsorbent substances like
'molecular sieves' to recover remaining gas molecules through
a temperature-controlled and pressure-controlled process.
CryoCondap® technology guarantees fridge recycling
plants that the CFC emission levels will fall below legal
limits - less than 20mg / m³ - complying with EU regulations
governing ODSs.
Cyclopentane, which is used in fridges manufactured after
1995, can be recovered using the same cryogenic condensation
method, in order to comply with the EU VOC Solvent Emissions
Directive.
During the recycling process a lot of dust is created which
under certain conditions, where there is enough oxygen and
a source of ignition or a 'spark', can cause fire or an
explosion. When cyclopentane from the new generation fridges
is present and is recovered, the concentration becomes so
high that it too can ignite in this environment.
As there are often 'sparks' in a shredder and the dust
and VOC concentrations can be sufficient to be flammable,
oxygen levels must be kept very low. This is achieved by
flushing the system with nitrogen, in order to make it inert.
The liquid nitrogen used for cooling will vaporise and this
nitrogen gas is re-used for inerting the process. Oxygen
levels are monitored throughout the process to ensure safe
operation.
Fridge recycling in the future
New generation fridges currently account for between 2-4%
of the fridge recycling market in Europe. In 10 years this
will have increased to between 30-40 %. Therefore, demand
for cryogenic condensation technology in the fridge recycling
market is expected to grow as plants recognise the benefits
of investing in technology capable of meeting emissions
recovery targets now and in the future.
VOCs and the environment
Volatile Organic Compounds or VOCs cause higher ozone concentrations,
through chemical reactions, in the lower atmosphere and
this is leading to health issues for flora and fauna as
well as contributing to global warming.
CFCs and HCFCs and the environment
Chlorofluorocarbons (CFCs) and Hydrochlorofluorocarbons
(HCFCs) break down the ozone in the higher layers of the
atmosphere - the stratosphere - where ozone is beneficial
to the environment because it protects us from UV light.
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