Optimization of an Integrated System for Refinery Wastewater Treatment

The Fenton and intermittent discharge aerobic bioreactor with continuous flow is used for refinery wastewater treatment. In the Fenton process, the maximum efficiency was obtained at a contact time of 20 min, pH 3, and H2O2/Fe+2 ratio of 15. In the biological treatment, MLSS and aeration time have positive and direct effect on the process efficiency. The maximum COD removal in Fenton, biological, and integrated process was 80.7, 55.14, and 94.21%, respectively. These values for BOD removal were 75.6, 40, and 92.22%, respectively. The type of models for the Fenton and biological treatment were the quadratic and linear model, respectively, according to RSM.