the electrons donated by the influent Mn concentrations
could well result in a loss of 0.113 mg/L TN if the intermediate
product of NH4 + -N oxidation (NO2
-N) was denitrified, or a loss
of 0.07 mg/L TN if NO3
-N was denitrified. Obviously, the electrons
donated by Mn were insufficient to cause a significant TN loss in
phases II and III, as is shown in Fig. 3b.These results indicated that
the denitrification of NO2
-N or NO3
-N, coupled to the Mn oxidation,
was not the reason for the significant TN loss.