High rate autotrophic denitrification in fluidized-bed biofilm reactors

•High rate, high efficiency autotrophic denitrification was demonstrated in a FBR.•Complete nitrate and nitrite removal was achieved at HRTs as low as 10min.•The nitrate and nitrite loading rates reached 600 and 228mgL−1h−1, respectively.•The biofilms were dominated by T. denitrificans and tolerated pHs as low as 5.8.•The optimal temperature for nitrate removal was 26.6°C based on Ratkowsky modeling.