The treatment of animal manure wastewater by coupled simultaneous methanogenesis and denitrification (SMD) and shortcut nitrification-denitrification (SND)

BACKGROUND The anaerobic–aerobic system is considered an efficient process for simultaneous removal of organic matter and nitrogen from animal manure wastewater. In this work, coupled simultaneous methanogenesis and denitrification (SMD) and shortcut nitrification–denitrification (SND) was investigated to treat animal manure wastewater having high concentrations of nitrogen and organic matter. RESULTS The best COD and NO2−-N removal efficiency was achieved when the influent COD loading rate in the anaerobic reactor was 3 kg m-3 d−1 and the COD/NO2−-N ratio was above 30. It was advantageous to the treatment of high-strength ammonia animal manure wastewater to adopt SND when the pH and free ammonia were about 8.0 and 18 mg L−1, respectively. The average efficiency of of removal COD, NH4+-N, and total nitrogen when adopting the coupling technology was 96.7%, 94.9% and 86.5%, respectively, and the nitrite accumulation rate reached 94.55%. CONCLUSION This study suggested that it was technically feasible to adopt SMD–SND coupling technology of to treat animal manure wastewater with high concentrations of nitrogen and organic matter. © 2013 Society of Chemical Industry © 2013 Society of Chemical Industry