Pretreatment of Olive Mill Wastewater using Chemical Coagulation (Anhydrous Ferric Chloride FeCl3)

Abstract

Olive mill wastewater (OMW) resulting from the olive oil extraction industry is a major pollutant, due to its high organic load, phytotoxic phenolic compounds, and its antibacterial nature that resists biodegradation. Several physical, chemical, and biological techniques have been proposed for the effective treatment of olive mill wastewater (OMW), but all of them have advantages and disadvantages that must be overcome. Based on the lack of studies that determine the optimal dosage of anhydrous FeCl₃ as a pretreatment for the wastewater of three-stage olive mills in the Syrian coastal region, this research aims to study the use of chemical coagulation as a pretreatment step, with the goal of reducing the content of organic compounds and phenolic compounds in this water, with a simultaneous evaluation of (COD-TPC-TSS). The first step was to improve the coagulation process by determining the dosage of the coagulant, in which the Jar Test device was used with the appropriate amount of coagulant added directly to the sample. Anhydrous iron chloride was used at doses ranging from 2-12 g/L. The removal efficiencies were 33.1% for chemical oxygen demand (COD), 60.33% for total phenolic compounds (TPC), and 94.04% for suspended solids (TSS). This study indicates that the use of anhydrous iron chloride (FeCl3) can be an effective primary treatment method in OMW water treatment.