Biodegradation of high phenol concentration by activated sludge in an immersed membrane bioreactor

The effect of adaptation of mixed culture in the phenol biodegradation has been studied. The degradation experiments have been conducted at different phenol concentrations from 0.5 to 3 g L−1. Biological treatment has been shown to be economical, practical and it leads to a complete removal of phenol. High concentrations of phenol are inhibitory for growth; so it is for the rates of substrates utilization that are greater at low initial concentrations. Haldane kinetics model for single substrate was used to obtain maximum specific growth rates (μm = 0.438 h−1), half saturation (Ks = 29.54 mg L−1) and substrate inhibition constant (Ki = 72.45 mg L−1). Although the concentration in phenol is significant, these results are in agreement with those reported in the literature for phenol removal abilities in different systems and the Haldane model is still acceptable.