Industrial Plant for Olive-Mill Wastewater from Two-Phase Treatment by Chemical Oxidation

Olive-oil production generates high and variable amounts of wastewaters from the olives and olive-oil washing (OMW), resulting to great environmental impact. These waters are normally stored in large holding ponds for evaporation during the summer. The present study examines the chemical-oxidation process using ferric chloride catalyst for the activation of H2O2 (Fenton reaction). Tests have been made on an industrial scale. The final average value of chemical oxygen demand (COD) was close to 371 mg O-2 L-1 (%CODremoval = 86%, CODinitial = 2684 mg O-2 L-1), and the water produced can be used for irrigation or can be discharged directly into the municipal wastewater system for tertiary treatment.