염분 주입 농도에 따른 아나목스의 공정성능 효율과 바이오매스 스트레스 = Anammox performance efficiency and biomass stress at different feed NaCl concentrations

다국어 초록 (Multilingual Abstract)

In this study, two six hourly cyclical lab-scale sequencing batch reactors were used to study the performance of Anammox bacteria at various saline conditions ranging between 0.1%, 0.3%, 0.5% to 2% NaCl concentration increased in steps. The two reactors with operational volume of 1.8 L were operated for 200 days with the stirrer mixing speed set at 120 rpm. The nitrogen loading rate (NLR) fed to the SBRs was maintained at 0.36 g N (L day)-1 throughout the operational period. A combination of Argon and CO2 gas was used to maintain an anaerobic environment within the reactors alongside controlling the pH at a maximum set point of 7.9. At the initial set-up phase, the seed biomass acclimation to the lab scale reactors showed an inconsistent performance however, a stable performance was observed after about 30 days of operation. The substrate removal efficiency predominantly ranged between 95 - 98% during most of the operational period. Reaction molar ratios Rs and Rp determined experimentally from the substrate utilization rates were approximately 1.13 and 0.31 respectively. The averagely steady total suspended solids (TSS) and volatile suspended solids (VSS) in both reactors prevented the need for biomass re-seeding. Anammox biomass stress index; a ratio of the dissolved adenosine triphosphate (dATP) to the total adenosine triphosphate (tATP), determined using LuminUltra microbial monitoring kits showed a definite correlation between the NaCl concentration and biomass stress. Biomass stress recovery to acceptable ranges (< 20%) was observed after few operational cycles at lower NaCl concentrations and vise versa. The Specific Anammox activity pragmatically remained constant for the biomass and the average nitrogen removal efficiency (NRE) was 80%.