Abstract
High energy recoveries with low sludge build-up using anaerobic digestion.
[Display omitted]
•Anaerobic treatment of PCP containing wastewater with high biogas production rates.•High PCP concentrations decrease the COD removal and inhibit methanogenesis.•Effect of co-substrates on PCP decomposition and biogas production investigated.•Biogas production, 80% COD removal, 90% PCP removal through anaerobic digestion.
This study aims to examine the effect of different co-substrates on the anaerobic degradation of pentachlorophenol (PCP) with simultaneous production of biogas. Acetate and glucose were added as co-substrates to monitor and compare the methanogenic reaction during PCP degradation. During the experiment, a chemical oxygen demand (COD) removal efficiency of 80% was achieved. Methane (CH4) production was higher in glucose-fed anaerobic reactors with the highest amount of CH4 (303.3µL) produced at 200ppm of PCP. Scanning electron microscopy (SEM) demonstrates the high porous structure of anaerobic sludge with uniform channels confirming better mass transfer and high PCP removal. Quantitative real-time PCR (qPCR) revealed that methanogens were the dominating species while some sulfate reducing bacteria (SRBs) were also found in the reactors. The study shows that strategic operation of the anaerobic reactor can be a feasible option for efficient degradation of complex substrates like PCP along with the production of biogas.