System for the biological treatment of aerobic wastewater with fixed culture in two phases
In the immersed phase, the biomass breaks down the organic material by aerobic fermentation using the the environmental oxygen from the emerged phase.
The heaviest solids and the floating solids in the wastewater are sedimented in the primary decanters. Then the water is routed towards the secondary biological treatment by pumping.
The discs are semi-emerged in the effluent to be treated and actuated by a rotating movement which mixes and aerates it at the same time. The bacteria culture develops and forms a purifying biofilm on the surface of the discs. This absorbs the organic material dissolved when it is submerged and is then saturated with oxygen as soon as the discs move into the open air, which favours the growth of the biomass. When said biomass is thick enough a certain quantity of it detaches itself and mixes with the water to be treated.
The biodiscs are provided with a basin and a chassis so that they can be installed either above ground or semi-underground.
The sludge that has detached itself from the surface of the biological discs and mixed with the water to be treated is separated with the lamellar clarifier. The inclination of the lamellas prevents most of the solids leaving.
Low electricity consumption.
Easy to operate.
Low sensitivity to organic and hydraulic load variations.