Biodegradation of high strength phenolic wastewater using SBR

This investigation demonstrates the capability of a bench-scale sequencing batch reactor (SBR) to biodegrade an inhibitory substrate at a high loading rate. A SBR loading rate of 3.12 kg phenol.m³d^-1 (2.1 g COD.g^-1 MLVSS d^-1) with a COD removal efficiency of 97% at a SRT of 4 days and a HRT of 10 hours was achieved; this rate was not reached before. The SBR was operated at 4 hours cycle, including 3 hours react phase. The synthetic wastewater of 1300 mg/L phenol was the sole carbon source.

Oxygen uptake rates (OUR) were monitored in-situ at various stages of the SBR. The oxygen mass transfer coefficient, K_La, of 12.6 h^-1 was derived from respirometry.Use of respirometry in SBR aided the tracking of the soluble substrate through OUR.