Table 1 Summary of reactor performances of the O/A/O/EI and A/O/A/O reactors during steady-state operationa

From: An efficient process for wastewater treatment to mitigate free nitrous acid generation and its inhibition on biological phosphorus removal

Item O/A/O/EI reactor A/O/A/O reactor
Effluent SOP (mg/L) 0.41 ± 0.11 2.70 ± 0.18
SOP removal efficiency (%) 97 ± 0.73 82 ± 1.2
Effluent NH4+-N (mg/L) 2.68 ± 0.41 3.75 ± 0.15
Effluent NO2--N (mg/L) 0.23 ± 0.08 0.31 ± 0.03
Effluent NO3--N (mg/L) 0.85 ± 0.21 1.21 ± 0.09
Effluent pH </city>8.6 ± 0.2 8.1 ± 0.3
TN removal efficiency (%) 89 ± 1.8 85 ± 2.1
  1. aResults are the average and standard deviation and the data were obtained during the steady-state operation.