Treatment of Olive Mill Wastewaters in Soil Slurries.

In the present research work we propose to use agricultural soil as a catalyst for the detoxification of Olive Mill Watewaters (OMW). The reaction is carried out in a soil-OMW slurry in an aerated, stirred reactor in order to ensure optimal conditions for the oxidation of OMW polyphenols catalyzed by soil iron and manganese oxides and by endogenous microbial polyphenol oxidases. The scope is to reduce substantially the concentration of free polyphenols in the OMW without reducing the total organic and mineral load. After the treatment, the OMW could be reused for field fertigation or submitted to further biodepuration without the constraints imposed by the microbial and phyto- toxicity of the polyphenols.