A new oxic-settling-anaerobic (NOSA(®)) activated sludge process for minimizing excess sludge in secondary biological treatment plants: a pilot-scale evaluation of the absorption-biodegradation process.
This study compared the sludge reduction performance of a new oxic-settling-anaerobic (NOSA) process with that of a conventional adsorption-biodegradation process. A 50 m(3)/d pilot trial system with two different process configurations was operated for 6 months. The NOSA process functioned effectively in removing both chemical oxygen demand and nitrogen with the efficiencies of 86 and 92.5%, respectively, which reduced approximately 40% of the excess sludge. In this research, 0.77 kg volatile suspended solids/d sludge vanished in the anaerobic tank, which accounted for 58.9% of the total sludge loss in the NOSA process. Economic calculation suggests that the new process can dramatically upgrade the sludge reduction in wastewater treatment plants without a digestion device, and the investment for fundamental upgrading can be recovered in 5-6 years by cutting the costs of excess sludge dewatering and disposal treatment.
School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, China.
Ke
K
Wu
Shi-Yu
SY
Li
Feng
F
Jiang
Jun
J
Wang
Guang-Li
GL
Liu
Guang-Hao
GH
Chen
D000042:Absorption; D000693:Anaerobiosis; D001673:Biodegradation, Environmental; D004867:Equipment Design; D010865:Pilot Projects; D012722:Sewage / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000295:instrumentation* / Q000379:methods*
D012722:Sewage