UPGRADING OF WASTE-WATER TREATMENT PLANTS FOR THE BIOLOGICAL NITROGEN ELIMINATION BY THE INJECTION OF ONLINE PREPARED MIXED CULTURES

By mixing of defined single bacterial and yeast strains with known biokinetic and growth properties, it is possible to prepare various efficient designed mixed cultures for the biodegradation of defined persistent substances and their derivatives. Preparing the mixed cultures on line in separate propagators and enriching the activated sludges semi-continously by injection of the mixed culture into the activated sludge reactor it is possible to improve the biodegradation efficiency of waste water treatment plants. Applying this technology in a cokery effluents treating plant designed for the removal of COD and phenols, additionally to an improved COD-removal it succeeded in establishing a very efficient nitrification. Injecting a mixed culture, containing oxygen tolerant denitrifying strains into the municipal waste water treatment plant of Salzburg it was possible to establish a simultaneous nitrification and denitrification under aerobic conditions