De-nitrification is the biological process that reduces molecular gaseous nitrogen.
It
is mainly realized in an anoxic tank, put in front of the actived
sludge one, powered by the effluent from the primary treatments, from
secondary sedimentation sludge return and turbid return from the
oxidation tank.
The quantity of nitrogen in the effluent treated is reduced and is subsequently released, Through de-nitrification.
The
de-nitrifying micro-organisms metabolise the organic substance using
nitrate oxygen as the oxygen source and reducing it to nitrogen.
Therefore, the residual products of the de-nitrification reaction, are micro-organisms and gaseous nitrogen.
The
reaction occurs in specific tanks in which sludge return containing
de-nitrifying bacteria and/or effluent, containing nitrates and
deriving from the oxidation-nitrification process, the inward waste
water containing biodegradable organic carbon come into contact.
