VERDER CARBOLITE GERO AAF 11/32, Installation, Operation And Maintenance Instructions, Page: 15 / 36

5.6 Thermal Catalytic Oxidiser Option
Catalytic oxidation allows the purification of exhaust air from volatile organic
components at low temperature without an open flame. By the use of a suitable
catalyst, complete oxidation of the volatiles takes place at temperatures between 250°C
and 400°C. Due to the low reaction temperature, catalytic oxidisers require very little
energy. Compared to other exhaust gas purification systems, the catalytic oxidiser has
a very small footprint.
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The catalyst system has its own power cord and should be powered from a ded-
icated source, separate from the furnace supply. The catalyst system has a power
rating of 2.5kW, and requires a 220-240 volt power supply.
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Always power up the catalyst before heating up the furnace.
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Cool the furnace down below 250°C before turning off the catalyst power supply.
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The catalyst fan has the effect of lowering the pressure in the furnace chamber and
assisting fume extraction from the furnace.
Note : To avoid damage to the catalyst system, the catalyst fan must always be
running whenever the furnace is hot.
The larger model (32 litre) furnace catalyst has a fan speed control; this should be set
at maximum speed initially. During the ashing process the catalyst fan speed may be
reduced if required, but not beyond the point where smoke escapes from the furnace
door area. It is recommended not to lower the speed below 50%.
Avoid overloading the catalyst system with volatiles. Particulate matter will not be
catalysed, so if carbon particles are visible in the exhaust stream, slow the furnace heat
up rate and/or reduce the load in the furnace. The furnace should not be loaded when
hot, as the rapid evolution of volatiles may be too great for the system to cope with.
If the catalytic effect fails and smoke is constantly exhausted, this may be the result of
a poisoned catalyst, failed catalyst heating element or failed exhaust fan.
These items are available as spare parts from Carbolite Gero.
Note: The addition of the catalytic afterburner option increases the external
dimensions of the furnace. Please refer to the Specifications section of this manual
for amended dimensions.
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5.0 Operation