Simultaneous nitrification and denitrification using Siporax™ packing

In this paper, we examine a biofilm process for simultaneous removal of ammonia and NOx (nitrite and nitrate). Siporax™, a porous Raschig-ring type filter specifically designed and manufactured for fast colonisation by micro-organisms, was used to demonstrate the feasibility of simultaneous nitrification (usually an aerobic process) and denitrification (usually an anaerobic or anoxic process) inside a single reactor. Clear evidence was found that denitrification occurred inside the internal pore structure of Siporax ™rather than in an anoxic zone near the outlet of the reactor. The reactor was operated continuously and maximum nitrification and denitrification capacities of 0.61 and 0.83 g N/(1.day), respectively were observed in this study.