Biofiltro aerado submerso
Default

Input data

Flow

Output data

Description

Given the values of average incoming flow, average incoming BOD, dimntions occupied by biomedia, specific area of the biomedia,air volume to be applied to BOD mass unit and intended washwater rate, calculates the values of volumetric organic load, superficial organic load, air flow to be applied and minimum flow which allows to reach the intended washwater rate.

Submerged aerated biofilter

Grades

  • This depth must not be less than 1.60 m.
  • This specific surface area must not be less than 350 m²/m³. It can also be inert material of synthetic or mineral origin, with a size of 2 to 6 mm.
  • The applied volumetric organic load must be equal to or less than 4 kg BOD/(m³.d)
  • The applied surface organic load must be less than 15 g BOD/(m².d) (referring to the specific surface of the support medium); In cases also aiming at nitrification, the applied ammonia nitrogen load cannot exceed 1 g N / (m².d)
  • Aeration must be uniformly distributed, at a minimum rate of 30 Nm³ air/kg BOD applied to remove organic matter
  • The hydraulic washing rate must be equal to or greater than 600 m³/(m².d)
  • Submerged aerated biofilters require removal of excess biomass by backwashing. They do not require the use of secondary decanters.

References

  • ABNT. NBR 12299. Elaboração de projetos hidráulico-sanitários de estações de tratamento de esgotos sanitários. Rio de Janeiro: ABNT, 2011.