Kinetic Study of 4-Chlorophenol Biodegradation by Acclimated Sludge in a Packed Bed Reactor

Abstract

In this study, batch experiments were conducted to evaluate the degradation of 4-CP using acclimated sludge. The Monod and Haldane models were employed to fit the specific growth rate with various initial 4-CP concentrations of 67–412 mg/L in the batch experiments. Haldane kinetics showed a better fit to experimental results than Monod kinetics. The kinetic parameters were obtained from a comparison of Monod and Haldane kinetics with batch experimental data. The values of μm and KS were found to be 0.691 d−1 and 5.62 mg/L, respectively, for Monod kinetics. In contrast, the values of μm, KS, and KI were 1.30 d−1, 8.38 mg/L, and 279.4 mg/L, respectively, for Haldane kinetics. The kinetic parameters in Haldane kinetics were used as input parameters for the kinetic model system of the packed bed reactor (PBR). The continuous flow PBR was conducted to validate the kinetic model system. The model-simulated results agreed well with experimental data in the PBR performance operation. At the steady-state stage, the removal efficiency of 4-CP was 70.8–96.1%, while the hydraulic retention time (HRT) was 2.5 to 12.4 h. The corresponding removal of 4-CP was assessed to be 94.6 and 96.1% when the inlet 4-CP loading rate was increased from 0.11 to 0.51 kg/m3-d. The approaches of kinetic models and experiments presented in this study can be applied to design a PBR for 4-CP treatment in wastewater from the effluents of various industries.