Denitrification potential enhancement by addition of anaerobic fermentation products from the organic fraction of municipal solid waste

The aim of this study is to demonstrate the denitrification potential enhan cement determined by the addition of the anaerobic fermentation products fr om the organic fraction of municipal solid waste in BNR wastewater treatmen t plants. The denitrification potential rose from 6 to 17 mgNO(3)-N/l thank s to the good performances showed by the fermentation products in the denit rification step: a typical maximum denitrification rate of about 5 mgN/gVSS d was observed. This value is similar to those obtained by using pure orga nic substrates. The denitrification capacity increase is determined by a si gnificant increase of S-s and X-s, availability in the influent due to the anaerobic fermentation products addition which leads to an influent COD inc rease equal to 68% of the total load: this value is significantly higher th an the one obtained by fermentation of primary and/or waste activated sludg e (3-5%).