Qualitative Characterization of Liquid Effluents Olive and Estimation of Energy Potential in the Delegation of Kalâa Kebira (Tunisia)

Abstract

Liquid effluents olive (Aqueous phase from the extraction of olive oil) imply an adverse effect on the environment due to the great quantities annually produced, the contamination risks related to their high level of pollution and toxicity and for their difficult biodegradable polyphenol content and high Biological Oxygen Demand (BOD₅). The search for performance technology for the treatment of Oil Mill Wastewater (OMW) becomes an urgent necessity prior to any discharge. In this perspective, we conducted an investigation on the quantitative characterization (estimated availability) and qualitative (Chemical parameters and indicators of pollution) of OMW, to assess their ability to Biomethanation in the delegation of Kalâa Kebira (Sousse, Tunisia). The samples had an average pH value of about 4.6, an average electrical conductivity too high (12.48 mS/cm), a relatively acceptable chloride concentration (1.5 g/L), a ratio COD/BOD₅ of 1.91 and a strong wealth oxidizable material. All these features ensure that the implementation of OMW anaerobic digestion process is difficult, but it is still possible, providing high efficiency energy from 85 to 93% and an a production of about 57 L of biogas, from one liter of OMW.