Treatment of olive-mill wastewater from a two-phase process by chemical oxidation on an industrial scale

Abstract

This study offers a solution for reducing the environmental effect of wastewaters generated by the olive-oil industry. Olive-oil companies produce variable quantities of wastewaters, which require treatment for disposal or reuse. Today, regulations are becoming increasingly strict regarding the parameters measured in these effluents. In Spain, the resolution by the president of the Hydrographical Confederation of the Guadalquivir on water use 2004 set parameter limits as follows: pH = 6.0–9.0, total suspended solid = 500 mg/L; and COD and BOD520=1,500 mg O2/L. For the year 2006, maximum values for COD and BOD520 were fixed at 1,000 mg O2/L. To solve this problem, a study has been made to derive irrigation water from the above-mentioned effluents through chemical oxidation based on the Fenton's process. This would be first step towards using a closed-circuit system in olive-oil mills to treat and reuse effluents.