Overview

Nitrogen removal „for free“

Nitrogen removal is the most important cost factor in wastewater treatment besides sludge treatment. The DEMON® process is a very efficient and cost effective solution for nitrogen removal.
DEMON® involves two process steps - the partial nitritation of ammonia and the subsequent anaerobic oxidation of residual ammonia by nitrite to nitrogen gas. Both process steps are catalysed by different consortia of organisms. i.e. a population of aerobic autotrophic ammonia oxidizers and a consortium of anaerobic autotrophic ammonia oxidizers (ANAMMOX). DEMON® requires a stochiomeric oxygen demand of only 40 % compared to complete nitrification. No carbon dosage is required due to the autotrophic nature of the process
The method technically is performed in a SBR plant in which the individual steps take place in a temporal consequence after each other. The intensely red colour of the biological sludge is typical. The DEMON®-sludge forms great dense pellets (10¹⁰ cells ml^-1). The growth rate of this sludge is very low, why a high sludge retention time is mandatory. The DEMON® system was developed and patented by the University of Innsbruck .

created by onelook Links