הנדסת מים

34 130 | מגזין המים הישראלי הנדסת מים | כנס כנרת להנדסה וחדשנות בתחום המים ע״ש פרופסור נוח גליל Observed TAN removal rates reached up to 6 g/d/m2 and corresponds to previous results obtained in the lab and smaller scale pilot testing published previously (Shechter, 2020). After 1.5 months of operation, the effluent NO2- concentration decreased without an increase in effluent NO3-, which implies that denitritation or annamox processes have potentially developed in the reactor (Lackner, 2020). New generation sequencing (NGS) analysis on biofilm samples taken fromdifferent parts of the membrane (Figure 2), show that the microbial population is especially rich in AOBs (over 10%) andthat neither anammoxnorNOBs were observed, whereas nitrite and nitrate reducing species were present to some extent (also about 10%). These results support the hypothesis that the MABR system removed ammoniacompounds vianitritationandpartial denitritation. CONCLUSIONS Results of nitrogen species distribution over the first months of operation, from start up to stabilization, are shown in Figure 1. The nitrification rates appear to increase gradually and stabilize around an average of 5 gN/d/m 2 , along with no corresponding increase in nitrate (NO3¬-), indicating that nitrogen removal processes have taken place, including partial nitritation denitritation and anammox. These results imply that MABR can provide stable, energy efficient shortcut nitrogen removal for high concentration streams such as centrate from anaerobic sludge digestion. In the comingmonths, wewill conclude a final analysis of the second NGS sample. So far, anammox has beenobservedat approximately 1.5-2%.