Respirometric evaluation and modeling of theimpact of continuous benzo[a]anthracenefeeding on activated sludge
Citation
Basak, S., Güven, D., Çokgör, E., & Orhon, D. (2019). Respirometric evaluation and modeling of the impact of continuous benzo [a] anthracene feeding on activated sludge. Journal of Chemical Technology & Biotechnology, 94(8), 2621-2629. DOİ: 10.1002/jctb.6071.Abstract
BACKGROUND: This study evaluated the impact of continuous benzo[a]anthracene (B[a]A) feeding on the biodegradation ofpeptone/meat extract mixture by means of respirometric testing and modeling results, and microbial community analyses.A sequencing batch reactor (SBR) was operated at a sludge age of 10 days. At steady state, it was sustained with thepeptone mixture feeding alone for 21 days. The following 21 days involved continuous dosing of 11 mg L−1of B[a]A togetherwith peptone mixture. In the last period of 7 days, B[a]A feeding was stopped. Storage of poly-hydroxy alkanoates (PHA)occurred during substrate utilization. A compatible model was calibrated using the oxygen uptake rate (OUR) and PHA profilescharacterizing each phase.RESULTS: Continuous exposure to B[a]A did not affect the microbial growth process, but slightly increased PHA storage rate andgrowth on stored PHA. Hydrolysis rates were increased at first exposure followed by a significant decrease. Substrate bindingalso occurred at first exposure and declined by the end of B[a]A feeding. A major change was observed in biomass compositiondue to continuous exposure to B[a]A.CONCLUSION: The major novelty of the study was to prove that B[a]A altered the composition of the enriched microbial culture,characterized by slightly different process kinetics, especially for hydrolysable COD fractions.© 2019 Society of Chemical Industry