THE IMPLEMENTATION OF BIOLOGICAL PHOSPHORUS AND NITROGEN REMOVAL WITH THE BIO-DENIPHO PROCESS ON A 265,000 PE TREATMENT-PLANT

A process, called Bio-Denipho, for combined biological phosphorus and nitrogen removal in a combination of an anaerobic tank and two oxidation ditches is described. In this process the anaerobic tank consisting of three sections working in series is followed by two oxidation ditches. These too are working in series, but with both inlet to and outlet from the tanks changing in a cycle. The Bio-Denipho process is described specifically for the process itself and as a case study for the implementation of the process on a 265,000 pe wastewater treatment plant for the city of Aalborg in Denmark. The plant was designed and erected in two stages and the last stage was inaugurated October 31, 1989. Lay-out and functions for the plant is described and design loads, plan lay-out and tank volumes are given in this paper together with performance data for the first year in operation.