Fixed biofilm processes are used in the biological treatment of wastewater. Trickle filters are based on these processes. A pump transports waste water from the supply unit to the upper end of the trickle filter. The waste water falls into the drip filter using a rotating distributor. In the trickle filter there is a fixed bed consisting of special support material. On this carrier material there is a thin layer of microorganisms (biofilm). As the wastewater flows through the fixed bed, microorganisms clean the wastewater by biological processes. The degradation of organic substances preferably takes place in the upper region of the drip filter. In the lower region, on the other hand, the oxidation of ammonium to nitrate (nitrification) is the predominant process. Subsequently, the wastewater flows into a collection tank. Two pumps return a part of the collected wastewater to the rotating distributor (recirculation).

Code: CE 701