Evaluation of sludge reduction and phosphorus recovery efficiencies in a new advanced wastewater treatment system using denitrifying polyphosphate accumulating organisms.
A new biological nutrient removal process, anaerobic-oxic-anoxic (A/O/A) system using denitrifying polyphosphate-accumulating organisms (DNPAOs), was proposed. To attain excess sludge reduction and phosphorus recovery, the A/O/A system equipped with ozonation tank and phosphorus adsorption column was operated for 92 days, and water quality of the effluent, sludge reduction efficiency, and phosphorus recovery efficiency were evaluated. As a result, TOC, T-N and T-P removal efficiency were 85%, 70% and 85%, respectively, throughout the operating period. These slightly lower removal efficiencies than conventional anaerobic-anoxic-oxic (A/A/O) processes were due to the unexpected microbial population in this system where DNPAOs were not the dominant group but normal polyphosphate-accumulating organisms (PAOs) that could not utilize nitrate and nitrite as electron acceptor became dominant. However, it was successfully demonstrated that 34-127% of sludge reduction and around 80% of phosphorus recovery were attained. In conclusion, the A/O/A system equipped with ozonation and phosphorus adsorption systems is useful as a new advanced wastewater treatment plant (WWTP) to resolve the problems of increasing excess sludge and depleted phosphorus.
Suzuki
Y
Y
Department of Chemical Engineering, Waseda University, 3-4-1 Ohkubo, Shinjuku-ku, Tokyo 169-8555, Japan. ys.jan0529@fuji.waseda.jp
Kondo
T
T
Nakagawa
K
K
Tsuneda
S
S
Hirata
A
A
Shimizu
Y
Y
Inamori
Y
Y
D000327:Adsorption; D019149:Bioreactors; D005798:Genes, Bacterial; D017404:In Situ Hybridization, Fluorescence; D009573:Nitrites; D010126:Ozone; D010758:Phosphorus / Q000737:chemistry*; D011122:Polyphosphates / Q000737:chemistry*; D012722:Sewage; D013997:Time Factors; D014865:Waste Disposal, Fluid / Q000379:methods*; D018508:Water Purification / Q000379:methods*; D015040:Zirconium / Q000737:chemistry
D009573:Nitrites; D011122:Polyphosphates; D012722:Sewage; D010758:Phosphorus; D010126:Ozone; D015040:Zirconium