Primary sludge fermentate as carbon source for mainstream partial denitrification–anammox (PdNA)

Primary sludge fermentate, a concentrated hydrolyzed wastewater carbon, was evaluated for use as an alternative carbon source mainstream partial denitrification–anammox (PdNA) in suspended growth activated process terms of denitrification (PdN) efficiency, PdNA nitrogen removal contributions, and final effluent quality. Fermenter operation at 2-day retention time (SRT) resulted the maximum achievable yield 0.14 ± 0.05 g sCOD/g VSS without release excessive ammonia phosphorus to system. Based on results batch experiments, fermentate addition led PdN efficiency 93 14%, which similar acetate nitrate residual 2–3 mg N/L. In pilot-scale deammonification reactor, using 49 24%, lower than (66 24% during period I 70 21% II), most probably due ammonium kinetics zone. Methanol cost-saving potential application main short-cut pathway estimated be 30% 55% depending achieved. Practitioner points (PdNA). operated 1 2 day SRT Although 93% achieved with around 49% pilot studies. Application can result significant methanol cost savings.