CONTROL OF PHENOL BIODEGRADATION BY USING CO2 EVOLUTION RATE AS AN ACTIVITY INDICATOR

The ability of the carbon dioxide evolution rate (CER) to serve as a control parameter during the acclimation and biodegradation of an aerobic mixed culture was studied. Phenol was used as the sole source of carbon and energy in a sequencing batch reactor system (SBR), coupled to an infrared gas analyser measuring the CO2 in the exit gas. Activated sludge from a wastewater treatment plant served as inoculum. The evolution of maximal CER during the acclimation process was followed and compared with the microbial activity. A good agreement between substrate removal rate and CER was observed. The CER proved to be representative of the microbial activity. Moreover, it was found that starvation periods had a negative effect on microbial activity (biodegradation rate).