Input data

Influet flow

Influent BOD

Influent COD

Media volume

Media specific area, in m²/m³ - see Note 1

Output data

Volumetric organic load - see Note 2

Superficial organic load - see Note 3

Expected BOD at the biological filter effluent

Expected BOD at the secondary settling tank effluent

Expected COD at the biological filter effluent

Expected COD at the secondary settling tank effluent

Description

This calculation is valid as a first approximation. It is applied only to organic surface loads up to 1,8 kg BOD/(m³.d) and sewage temperatures around 20°C. Given the influent average flow, BOO and COD , the media volume and specifid surface for a submerged aerated biofilter, estimates the outflow values of BOD and COD.

Submerged aerated biological filter

Notes

The specific surface of the media must be smaller than 250 m²/m³
According to Brazilian Standard NBR 12209:2011, the applied organic volumetric load must be equal or lower than 1,8 kg BOD/(m³.d)
According to Brazilian Standard NBR 12209:2011, the applied organic superficial load must be lower than 15 kg BOD/(m².d) - referring to the media specific surface.

References

Morello, Caroline G. Comportamento de um filtro biológico aerado submerso (Fbas) no pós-tratamento de um reator anaeróbio de leito fluidizado (RALF). Dissertação de Mestrado. Maringá, Universidade Estadual de Maringá, 2013.

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