Effect of Nitrogen Compounds and Organic Carbon Concentrations on $N_2O$ Emission during Denitrification

The effects of the compounds and concentrations of nitrogenous electron acceptor, the ratio of electron donor/electron acceptor (C/N), and the complexity of electron donor on the emission of during wastewater denitrification were quantitatively investigated in this study. The higher and concentrations, the more emission was observed. has strong effect on emission as it emitted morc than , 50 mg/L of -N gave the highest conversion (9.3%) and yield (9.8%) of while -N (50 mg/L) gave 5.6% conversion and 11.0% yield. Lower C/N ratio decreases nitrogen removal efficiency, but it increases the conversion of because of the incomplete denitrification by the limited organic carbon. When real domestic wastewater is used as the electron donor of the denitrification, emission is reduced to 1/10 of the emission when single carbon (acetate) is used. It is thought that multiple carbon source utilizes many denitrification pathways and it seems to be helpful for the reduction of emission.