Denitrification removal of nitric oxide in a rotating drum biofilter

A rotating drum biofilter (RDB) was applied and evaluated for nitric oxide (NO) removal by denitrification from a synthesized waste gas using glucose as carbon source. The effects of drum-rotating speed and empty bed residence time (EBRT) on NO removal were investigated under anaerobic conditions. With the increase of drum-rotating speed higher than 0.5 rpm and the decrease of EBRT at a certain feed loading rate, there existed a lower NO removal efficiency influenced by mass transfer. At an EBRT of 65 s and a drum-rotating speed of 0.5 rpm, NO removal efficiency was over 97.9% with inlet NO concentration of 524 ppm. When oxygen existed, NO was removed as the function of denitrification of the main role and chemical oxidation. With the increase of inlet oxygen concentration, denitrification decreased and chemical oxidation increased and the optimal inlet oxygen concentration of about 5.2% was obtained.