One-stage deammonification: nitrogen elimination at low costs

Abstract

Biological nitrogen elimination used to purify wastewater with high nitrogen contents can become a major cost factor, in particular when the wastewater in question contains only little amounts of biologically degradable carbon compounds. The use of new biological conversion methods and the application of compact operation technology, however, does allow us to save operation and investment costs. Currently, the focus of scientific interest is on deammonification, that is the direct conversion of ammonia into elementary nitrogen by autotrophic micro-organisms, because in contrast to conventional nitrification/denitrification this method requires considerably smaller amounts not only of carbon, but also of oxygen. Moreover, the use of compact biofilm technology makes it possible to considerably reduce the reaction tank volume. In the following we will present the operation results of both industrial plants and laboratory-scale units for the treatment of wastewater with high nitrogen loads, results which unequivocally show the favourable cost-effectiveness of the mentioned method combination and thus the economic viability inherent in the purposeful industrial utilisation of this technology.