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Sum parameter – Total Organic Carbon
Continuous TOC determination in the
chemical industry
SCA-130-603
The high demand for many different products be polluted with high salt loads. For TOC
from the chemical industry and the required determination in wastewater, catalytic
efficiency of the manufacturing processes combustion has become the method of
often requires around-the-clock production. choice based on its higher oxidation potential,
This results in huge amounts of wastewater. especially for particles.
This water mostly originates from flowing
water bodies. ■ Are high salt loads a problem?
During thermal catalytic combustion of the
test sample, the dissolved salts crystallize.
High salt loads can lead to pollution of the
catalyst, or even clogging of the system.
Maintenance measures (for instance
exchanging the catalyst) would then be
required in order to render the instrument
operational again. Of course, it is desirable to
keep the maintenance intervals as long as
possible.
■TOC-4200
Industrial wastewaters must be pretreated The TOC-4200 offers various possibilities to
before being discharged into public sewage keep the maintenance needs for highly
treatment plants. Direct discharge into water polluted samples at a minimum. The TOC-
bodies requires an extensive cleaning 4200 with catalytic combustion at 680 °C is a
process. This is why many large companies high-performance analyzer. This temperature
or industrial parks operate their own is lower than the melting point of sodium
wastewater treatment plants. chloride and will, therefore, prevent
deactivation of the active centers of the
■ TOC determination in industrial catalyst by a melt. The use of a platinum
wastewater catalyst ensures the complete conversion of
The TOC content (Total Organic Carbon) is a the organic compounds to CO 2. The highly
measure of the concentration of organically sensitive NDIR detector allows small injection
bound carbon and is an indication of the volumes (typically 20 - 50 µL) that reduce the
pollution level by organic compounds in absolute sample input onto the catalyst. A
wastewater. This is why the TOC is often further reduction can be achieved using the
used in sewage treatment plants as integrated dilution function.
measuring parameter to monitor and optimize
the treatment process and to calculate
pollution levels. The matrix in industrial
effluents can vary greatly and can – prior to
sewage treatment –
