Biological Digester Decanter (DDB)

It consists of two compartments. The first compartment is a digester with bell digester, where there is a settling of the sedimentable solid particles. Both the bottom sludge and the floating layer undergo fermentation, reducing the amount of sludge.

The hood located inside the reactor divides the reactor into a decantation zone (upper) and digestion zone (lower), allowing the passage of the digestion of the particles that settle and preventing the introduction of digestion gases into The settling zone.

The second compartment performs a biofiltration, passing the water through a specific large surface landfill that supports biomass, which oxidizes the organic matter that is still in the wastewater. The water outlet is at the bottom.


  • In general: An annual purge of sludge and fat.
  • Slightly clean the percolator filter with pressurized water to facilitate the release of biofilm (biological sludge attached to the biological filter).
  • Clean the upper dumps that distribute the water along the biological filter compartment with pressurized water.

NOTE: the unit with biological filter can be added to sewage treatment plants already installed.