Influence of Temperature on the Start-up of Membrane Bioreactor: Kinetic Study

The start-up phase of a membrane bioreactor (MBR) for municipal wastewater treatment was studied to determine the effect of temperature on the organic matter removal and heterotrophic kinetics. The MBR system was analyzed at hydraulic retention times (HRTs) of 6 h and 10 h and temperature values varying between 11.5 °C and 30.1 °C. Arrhenius and Monod models were used to evaluate the effect of temperature on the biological process of organic matter removal. At the most favorable conditions of HRT (10 h) and MLSS (6,000 mg L−1) corresponding to phase 4, the effect of these variables dominated over the temperature. Heterotrophic biomass from phase 2 (HRT = 10 h, MLSS = 4,000 mg L−1 and T = 30.1 °C) had the highest values of COD degradation rate (rsu,H).