Manual for Refrigeration Servicing Technicians - UNEP - Division of ...

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Refrigerant Management
Disposable and non-refillable cylinders
Available on the market are a type of cylinder called “non-refillable”
or “disposable” cylinders. These are sometimes used where the
supply infrastructure is less comprehensive, and it is less costly
for refrigerant suppliers who may expect their cylinders to become
lost. From both an environmental and safety perspective, the use of
disposable cylinders is considered to be very bad practice.
These containers are generally discharged after use, resulting in a lot
of refrigerant being released to the atmosphere. Furthermore, there
are often attempts to re-use these cylinders (for example, through
brazing new valves onto them to enable re-filling with refrigerant),
despite such practices being forbidden. Also, they tend to be
manufactured from thinner metal than the conventional, re-usable
cylinders, rendering them more susceptible to rusting and mechanical
damage over time. As such, their use is not recommended under any
circumstances.
In fact they are already prohibited in many countries, such as the
European Union member states and Australia and Canada. Other
countries are also working to implement similar rules. Mandating the
use of returnable, refillable containers was implemented as a key
measure to reduce GHG emissions by eliminating the possibility of the
eventual release of the residual product that unavoidably remains in
disposable refrigerant containers. These regulations had support from
the major refrigerant manufacturers and industry trade associations.
If a disposable cylinder has been used, before disposing of it, it
should be properly emptied. This requires the remaining refrigerant
to be recovered until the pressure has been reduced to pressure
of approximately 0.3 bar (absolute). The container’s valve must be
closed at this time and the container marked as empty. The container
is then ready for disposal. It is recommended that the cylinder valve
should then be opened to allow air to enter, and the cylinder should
be rendered useless (with the valve still open) by breaking off the
valve or puncturing the container. This will avoid misuse of the
container by untrained individuals. Used cylinders can be recycled
with other scrap metal. Never leave used cylinders with residual
refrigerant outdoors where the cylinder can rust. An abandoned
cylinder will eventually deteriorate and could potentially explode.
Refillable cylinders
Refillable cylinders are the standard receptacles available for the
storage and transportation of smaller quantities of refrigerant. They
normally range in size from about 5 litres to 110 litres (approximately
5 to 100 kg of CFC, HCFC or HFC refrigerant). The cylinders are
normally constructed from steel and have a combination valve,
with separate ports for refrigerant removal, refrigerant filling and
a pressure relief device. The port for refrigerant filling is normally
locked so that only the refrigerant supplier can gain access. Some
cylinders also have two separate removal ports: one for liquid and
another for vapour, if the cylinder is fitted with a dip-tube. There is
usually a metal collar around to the top of the cylinder to protect
the valve from mechanical damage. Both the cylinder itself and the
valve are usually subject to national regulations for their design,
fabrication, and testing.
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