Activity of nitrifying biofilm in the process of water treatment in diatomite bed

The study deals with the efficiency of removing ammonium nitrogen from water in biofiltration process. For the research purposes diatomite was used as packing of biological reactor. As a biofilter filler, diatomite was simultaneously the sorbent, the culture medium and the carrier of microorganisms. The biological activity of the bed was assessed taking account of the effectiveness of removing ammonia nitrogen in the process of nitrification and the time of biofilm formation. Diatomite stimulates the growth of biomass and the process of effective removal of ammonia nitrogen, reaching even 100%. SEM image proved that the surfaces of diatomite bed grains were overgrown with microorganisms. The biofilm structure was loose and porous, being characteristic of aerobic biofilm. The biofilm covered the entire grain surface.