Activated sludge activity in the treatment of anaerobic sludge digester supernatant

Magdalena Zielińska, Katarzyna Bernat, Dorota Kulikowska, Agnieszka Cydzik-Kwiatkowska, Irena Wojnowska-Baryła
2012 Environment Protection Engineering  
The objective of the study was to examine the effect of the food/microorganisms (F/M) ratio on the respirometry of activated sludge treating anaerobic sludge digester supernatant at low oxygen concentration (DO) of 0.7 mg O 2 /dm 3 . Exogenous respiration rate (SOUR 1 ), endogenous respiration rate (SOUR 3 ) and the rate of oxygen uptake for nitrification (SOUR 2 ) were evaluated. Taking into consideration that BOD 5 /COD in anaerobic digester supernatant was 0.53, it may be supposed that weak
more » ... supposed that weak activity of heterotrophic bacteria (low SOUR 1 ) resulted from low DO concentration in the reactor, and not from limited accessibility of biodegradable substrate. At the F/M ratio of 0.05-0.26 g COD/(g TSS·d), SOUR 2 was from 2.1-fold to 20.6-fold higher than SOUR 1 . Further increase in the F/M ratio induced a decline in SOUR 2 but the efficiency of nitrification enhanced.
doi:10.37190/epe120402 fatcat:ujarsfc2undq5c6pdcobfzwfmi