Biofilm procedure with a high nitrification capacity at a wastewater temperature below 12 °C

Abstract

Nitrification in wastewater treatment is difficult in many cases at temperatures below 12 °C. The Fluid bed biofilm process is characterized by a very stable nitrification performance even at temperatures below 12 °C. It could be demonstrated by the authors by recording the Ammonium metabolism and the Ammonium oxidation capacity that the nitrification operated independently upon the temperature at a sludge loading rate up to 0,5 kg BOD/kg DW/day. Investigations on the basis of in-situ-hybridization (FISH) indicated that under these conditions Ammonium oxidizing microorganisms have been present in the biofilm at a sufficiently high number of cells.