WASTEWATER TREATMENT

摘要

The present invention provides a biological process for reducing the leve ls of nitrogen and phosphorous in wastewater, wherein said wastewater compri ses at least 100mg/L total nitrogen wherein said process comprises feeding s aid wastewater into a reaction vessel in at least two steps, wherein said re action vessel comprises an active biomass comprising nitrifying and denitrif ying organisms and polyphosphate accumulating organisms (PAOs), wherein at l east the first feed step is followed by a non-aerated period of sufficient d uration to result in sufficiently low concentrations of NOx species in the w astewater to allow for accumulation of polyhydroxyalkanoates in the PAOs, an d at least the first non-aerated period is followed by an aerated period of sufficient duration to allow for ammonium oxidation by the nitrifying organi sms and assimilation by the PAOs of at least a portion of the phosphorous in the wastewater.