Can nitrifiers from the sidestream deammonification process be a remedy for the N-overload of the mainstream reactor?

How to Provide Nitrite Robustly for Anaerobic Ammonium Oxidation in Mainstream Nitrogen Removal

“…Side stream treatment can also achieve the bioaugmentation of ammonia oxidizers, avoiding the washout and the decrease of ammonia oxidizers in the mainstream PN systems. ,, The bioaugmentation of ammonia oxidizers cultivated by side stream centrate has been used in lab- and pilot-scale systems to increase the AOB/NOB ratio by increasing the ammonia oxidizers amount (Table ). ,, Integrating side stream treatment toward mainstream is promising and attractive, but potentially is not easily adopted in practice, primarily because not all WWTPs have implemented anaerobic digesters and postpositional nitritation facilities. , Lack of these infrastructures restricts the adoption of promising side stream treatment technologies and strategies for achieving mainstream PN in practice. Additionally, the fluctuation of the nitrogen loading in a side stream centrate may have a negative influence on maintaining AOB activity and inhibiting NOB activity, as well as the introduction of recalcitrant organics posing an inhibitory effect on AnAOB …”

“…The side stream (reject water from anaerobic digested sludge) accounts for 1%−3% of daily flow and 15%−30% daily nitrogen loading of WWTPs. 105 The side stream and its postpositional nitritation effluent generally are characterized by high FA (150−1000 mg N/L) and FNA (10− 15 mg N/L), and can be used to treat mainstream recirculated sludge for stressing NOB and enhancing the activity of AnAOB. 23,26,39,70,106 Typically, there are two practices by integrating side stream treatment toward mainstream PN including (i) inducing side stream centrate (such as digestion liquor or reject water) into mainstream cotreatment 26,107 and (ii) implementing recirculated sludge treatment in a bypass treatment unit.…”

“…13,34,90 The bioaugmentation of ammonia oxidizers cultivated by side stream centrate has been used in lab-and pilot-scale systems to increase the AOB/NOB ratio by increasing the ammonia oxidizers amount (Table 3). 89,90,105 Integrating side stream treatment toward mainstream is promising and attractive, but potentially is not easily adopted in practice, primarily because not all WWTPs have implemented anaerobic digesters and postpositional nitritation facilities. 43,104 Lack of these infrastructures restricts the adoption of promising side stream treatment technologies and strategies for achieving mainstream PN in practice.…”

“…The side stream (reject water from anaerobic digested sludge) accounts for 1%–3% of daily flow and 15%–30% daily nitrogen loading of WWTPs . The side stream and its postpositional nitritation effluent generally are characterized by high FA (150–1000 mg N/L) and FNA (10–15 mg N/L), and can be used to treat mainstream recirculated sludge for stressing NOB and enhancing the activity of AnAOB. ,,,, …”