STUDY ON OILY WASTEWATER TREATMENT

Oily wastewaters are usually characterised by a high concentration of chemical oxygen demand (COD), suspended solids, dissolved solids (salts), toxicity, and refractory compounds. Therefore, it must be treated. The treatment of oily wastewater by Fe2O3/TiO2 was investigated. The effect of time, catalyst dosage, aeration, and pH on decolourisation was investigated. The results indicated that Fe2O3/TiO2 photocatalytic oxidation can decolourise oily wastewater effectively. Decolourisation efficiency increases with time, aeration and catalyst dosage increasing. But excessive catalyst and aeration decreased it, and decolourisation efficiency under acidic conditions is superior to alkaline conditions. Oily wastewater was treated under actual use of sunlight, Fe2O3/TiO2 catalyst, pH 3, the degradation rate was 39.2%, and COD removal - 46.7%.