ERFARENHETER FRÅN PILOTFÖRSÖK FÖR LÅNGTGÅENDE KVÄVEREDUKTION OCH FOSFORREDUKTION I DANMARK / Experiences from Pilot Tests in Denmark for Efficient Nitrogen and Phosphorus Removal
The demand in Denmark for efficient wastewater treatment has increased dramatically lately. Before 1993 most wastewater treatment plants must meet the effluent quality demand 15 mg/1 BOD, 8 mg/l nitrogen and 1.5 mg/1 phosphorus. This means that the nitrogen removal has to be in the order of 70-80 % also at low wastewater temperatures (6-7°C). PURAC AB cooperates in Denmark with the consulting company Nellemann og Partner A/S. Seven pilot tests have been carried out to find suitable solutions to reach the demands and to get data and experience for design of the full-scale plants. The system used was pre-denitrification and/or simultaneous precipitation. All pilot tests showed that the effluent quality demands could be reached using these process combinations. In several of the tests an external carbon source (methanol) had to be added due to a low ratio BOD:nitrogen. “Complete abstract not presented.”