Two ways to achieve an anammox influent from real reject water treatment at lab-scale: Partial SBR nitrification and SHARON process

High-throughput nitritation of reject water with a novel ammonium control loop: Stable effluent generation for anammox or heterotrophic denitritation

“…Finally, in spite of the lower rates achieved without pH control, these rates are much higher than those typically observed in SHARON reactors [9,29].…”

“…This decrease could be caused by differences in the conductivity and organic matter and salts content between the synthetic and real wastewaters. Nevertheless, the NLR achieved treating the reject water was very high compared with most of the bibliographic references of PN systems [5,9,26,27]. Moreover, the TNN/TAN ratio, which is the most important parameter for a subsequent anammox reactor, was stably maintained at 1.3±0.3, while the nitrate concentration in the effluent was always lower than 5 mg N L -1 .…”

“…The effluent with the required TNN/TAN ratio for the anammox step is achieved thanks to the bicarbonate/TAN ratio of the reject water, which typically contains the stoichiometric alkalinity required to oxidize around 50% of the inlet ammonium [9]. However, the treatment of wastewaters without the proper bicarbonate/TAN ratio or some fluctuations of influent TAN and alkalinity concentrations could strongly affect the TNN/TAN ratio of the effluent and therefore it could disturb the anammox process [10,11].…”

Anaerobic ammonium oxidation for treatment of ammonium-rich wastewaters

“…Full scale experience in Utrecht and Rotterdam wastewater treatment plants suggested that SRT between 1 and 2.5 d was acceptable (van Kempen et al, 2001). Nevertheless, SRT as long as 5 d in an SBR (sequential batch reactor) also created a favourable environment for AOB to outgrow NOB (Galí et al, 2007). 3.…”

“…Besides, if the DO concentration was limited, the process would remain stable with SRT as long as 24 d (Pollice et al, 2002). Both the SBR and the chemostat with the nitrogen conversion rates of 1.1 kg N/(d·m 3 ) and 0.35 kg N/(d·m 3 ) respectively were reliable reactors for the nitritation phase, whereas the chemostat was more stable (Galí et al, 2007). In engineering, cascade O 2 control plus pH control was superior to other strategies based on the economic cost analysis (Volcke et al, 2006).…”