Application and kinetic evaluation of upflow anaerobic biofilm reactor for nitrogen removal from wastewater by Anammox process

The lab-scale upflow anaerobic biofilm reactor was successfully operated for the treatment of synthetic wastewaterwith high nitrogen load by anammox (anaerobic ammonium oxidation) process. during the entire period ofoperation, the reactor temperature was kept at 35±1
c. the operational strategy consisted of both increasing theammonium and nitrite concentrations from 60 to 700mgn/l and from 80 to 920 mgn/l, respectively anddecreasing the hydraulic retention time from 24 to 6 h, at each step. the highest achieved removal efficiency ofammonium and nitrite were 91 and 93%, respectively. consequently, due to their acceptable performance fornitrogen removal in previous researches, modified stover-kincannon and grau second-order models were used inthis study. according to the experiment results, the model validity testing showed that the stover-kincannon modelwas a little more appropriate for the description of nitrogen removal in the reactor, even though both models gavehigh correlation coefficients (r2=0.999).