Activated charcoal filters remove AOX

Activated charcoal filters remove AOX

Many sectors require a sophisticated wastewater purification system to meet the applicable discharge standards. The smart removal of AOX also needs to be addressed. Using activated charcoal filters ensures that biological treatment plants are not overloaded and can perform in an extremely efficient way.

AOX is the collective name for adsorbable organic halides. Both biodegradable as well as non-biodegradable contaminated elements could be present in rainwater, washing water, process water or other sources. Wastewater that contains AOX may often only be discharged if the amount of AOX is below 1 mg/l.

Non-biodegradable AOX is present in such things as wastewater from paint, varnish and coating products, and presents a challenge for quite a number of sectors. It is not possible to eliminate these adsorbable organic halides using a biological treatment plant. The installation of a mobile activated charcoal filter before the biological treatment can resolve the problem simply and completely, enabling peak concentrations to be absorbed adequately and the discharge to remain below the maximum permitted levels.

Activated charcoal does not work selectively: as well as AOX, it also removes adsorbable COD. Once the filter is fully saturated with COD, displacement effects occur: the better adsorbable AOX is removed preferentially, enabling the removal of the penetrating COD to take place using biological purification.

Mobile activated charcoal filters are also effective during physico-chemical purification, which is also applied in processing liquid waste. After the coagulation and flocculation process of such a purification plant (in which non-biodegradable COD is removed), the Mobicon systems act as a control filter to reduce AOX concentrations to the absolute minimum. In both cases (pre-treatment of biological purification or control function for physico-chemical purification) our mobile activated charcoal units act as a cost-efficient solution for the removal of low AOX concentrations. Once they have reached the saturation point, Desotec ensures that these are replaced quickly.