Fully Biological Wastewater Treatment in Fixed Bed Process


The first chamber of the wastewater treatment plant is used for the separation of solids
(primary treatment).
From there, the wastewater flows for biological treatment into the second chamber.
Aerators are fixed to the bottom of the second chamber, which mix the wastewater
at regular intervals, with an exactly defined volume of air. The submerged fixed bed is
installed on top of the aerators (1)
The microorganisms available in the wastewater grow on it and form a „biofilm“ which
meets best „working conditions“ by the presence of nutrients in the wastewater in combination
with the determined aeration of the fixed bed.
Excess microorganisms are solved by the entraining air from the fixed bed again and
again, and then flushed with the biologically treated water into the third chamber for
secondary sedimentation. There they settle to the bottom as so-called excess sludge,
which is led back to the first chamber of the primary treatment via an airlift (2), before
the purified water leaves the wastewater treatment plant.