Kinetic behaviour of petroleum based oily wastewater treatment in a hybrid moving bed biofilm reactor

Performance of a laboratory scale moving bed hybrid bioreactor (MBHBR) was assessed in the present study under batch operation with varying concentration of oil and grease in wastewater sample in the range of 62–370 mg/L. Oily wastewater was fed in the MBHBR with polypropylene carriers in the temperature range of 18.5–25.7 °C and the pH range of 7.28–8.24. The study showed a maximum oil removal of 85.4% for an initial oil concentration of 275 mg/L under a contact time of 20 h. Monod’s kinetic theory has been applied to the results as obtained in the batch experimental study considering the contribution of both suspended and attached biomass. Various kinetic parameters were estimated as Maximum specific substrate utilisation rate, k = 0.32/d, Half saturation constant, Ks = 209 mg/L, Yield coefficient, Y = 0.728 mg/mg and Endogenous decay constant, k_d = 0.016/d. No major inhibition was observed during treatment of synthetic oily wastewater for the concentration range of 62–275 mg/L. The removal efficiency of oil was observed to be better in presence of attached biomass than suspended growth environment. The present study will be useful for the design of hybrid bio-reactors and for development of mathematical models under similar experimental condition.