A simple and effective method coupling coagulation and UV/TiO₂ photocatalysis for treating real-produced wastewater from oil processing

The complex composition of real-produced wastewater from oil processing poses significant challenges for wastewater treatment. The employed conventional methods have disadvantages such as low efficiency, high-cost demand, secondary waste, adverse effects on the environment and need to be intensified. The combined treatment of coagulation (carried out with Al₂(SO₄)₃) and photocatalysis (UV/TiO₂) was studied on wastewater produced from a SOCAR (Pirallahi dry well) oil extraction plant and synthetic paracetamol-based wastewater. Two different dosages of Degussa P25 catalyst at different pH conditions and ion presence were studied. Characterization of the produced wastewater showed the complexity of the treated matrix given the presence of inorganic ions and aromatic and aliphatic contaminants, and an important parameter that was reduced through coagulation was turbidity. The initial concentration expressed as THC was 714 mg/L. At the end of the treatment, a THC value of 210 mg/L was reached.