CAUTION!
It is imperative that a non-return valve is fitted
directly at the point of injection for the correct and
proper operation of the ozone generation system.
The pressure drop through the valve with a nom‐
inal gas flow rate must be low and the valve may
only be manufactured from ozone-resistant mate‐
rials. Recommended materials for this valve are
ceramic (Al
2
O
3
, ZrO
2
), non-corrosive steel and
PTFE. Operation without a non-return valve can
result in damage to the ozone generation system.
The valve should be fitted in such a way that no
foreign materials can penetrate the valve from the
raw water side and it should be serviced regularly.
The non-return valve can be supplied on request.
A stainless steel pipe is needed to provide the gas connection at
the point of injection. Stainless steel pipes and angle connectors
are available on request. Alternatively a PTFE pipe can be used.
CAUTION!
– For reasons of safety, the length of the pipe
and the number of removable connections
should be limited to a minimum. In accordance
with safety regulations applicable in Germany,
a gas detector is required in every room, which
contains a removable gas pipe connection.
– The complete pipework should undergo a
leakage test by a person with appropriate
experience once it has been laid.
7.3.2 Ozone removal from filters and reaction section
A reaction vessel may be required, depending on the use, to guar‐
antee a sufficiently long reaction time of the ozone with the raw
water to allow the ozone to produce its full effect. The substances
in the water are oxidised in the reaction vessel and the water is dis‐
infected. In many cases, dissolved residual ozone, destabilised col‐
loids, lumpy or coated micro-organisms and flocculated organic
reaction products may also have to be removed completely from
the water upstream of the discharge point. This can be done using
multi-layer filters, active carbon filters or mixed bed filters. Reaction
vessels and/or filters must be provided with an effective system for
the extraction of residual ozone from the system. This system must
be ozone-resistant and should also be checked regularly to ensure
that it is working correctly.
The pipework must be designed in such a way that it ensures that
no condensation flows back into the residual ozone destruction
vessel.
CAUTION!
If the correct and proper functioning of the removal
system in the filters or reaction vessels cannot be
guaranteed, there is a risk that ozoniferous water
may inadvertently pass through the system to the
discharge point. Service and maintenance to
comply with regulations is thus important.
Assembly and installation
32