Phosphorus removal from SBR with controlled denitrification for weak sewage

Most SBRs operating for weak sewage have a tendency of poor removal of phosphorus due to NO₃N inhibition. To minimize this inhibition, NO₃N storage was utilized in this study. With influent BOD 100 mg/L and VFA 30 mg/L, a total of the maximum removable nitrogen and phosphorus was about 25 mg/L with 8 hr cycle. With this storage, VFA utilized for phosphorus removal could be maximized. The effluent nitrogen and phosphorus levels were generally 11 and 1 mg/L, respectively.