Kinetic analysis of an anaerobic fixed-film fixed bed-reactor treating wastewater arising from production of a chemically synthesized pharmaceutical.

The kinetics of the treatment of a pharmaceutical wastewater (PW), pretreated in a first stage by electrocaogulation (EC), using an anaerobic fixed-film fixed-bed reactor was investigated. The experimental results for the substrate removal kinetics were found to be in good agreement with those of the Monod model and the modified Stover-Kincannon model, with a high regression value (R2 > 0.9). For the modified Stover-Kincannon model, the constants U(max), and K(B) were found to be 13.1 and 13.87 kg COD/(m3 x d) respectively. With reference to the biomass kinetics, the increase in organic loading rate (OLR) is attributed to the increased biomass growth rate (micro) and decrease in the biological constant K(micro). The corresponding constants for the modified Monod's model, i.e. 'micro(max) and decay constant K(d), were found to be 0.159 and 0.0113 d(-)1 respectively. Finally, the gas production kinetics was interpreted in relation to the Kincannon-Stover model.