Reduction of COD is a major issue for mixed type of waste water and many processes are used for reducing it including Fenton oxidation process (FO process). Many metals have special oxygen transfer properties which improve the utility of hydrogen peroxide; which is reactant of Fenton process. Fenton’s reagent is the result of reaction between hydrogen peroxide (H2O2) and ferrous iron (Fe2+), producing the hydroxyl radical (OH.). The main objective of this study is optimizing a semi batch process for FO process with varying operating conditions like flow rate, concentration, pH etc. This study also focus on modeling of reactor and effective sludge utilization generated during the process.