Physicochemical characterization of olive oil mill wastewaters samples collected from four different oil mills located in the Meknès-Tafilalt region of Morocco

Abstract

The purpose of this study is to realize a physico-chemical complete characterization of the olive oil mill wastewaters and metals mill contents in these last one.

For this, samples were obtained from four oil mills (press  system  and three phase system) located in the Meknes-Tafilalet region (Oued El Jadida Maya, Rabat road and Sidi Bouzekri) in  Morocco, between November and Mars in the olive period of 2014-2015 .

The composition of the OOMW changes significantly for each factory. The results  of the physicochemical analyzes showed that all the samples of olive oil mill wastewaters have an acidic pH whose mean value is between (5.22 and 5.75) and that the conductivity values vary due to the addition of salt during storage before grinding olives.

The OOMW are rich in organic matter .They are measured by the chemical oxygen demand (COD) and biological oxygen demand BOD₅. The average BOD₅, COD, polyphenols and biodegradability vary according to the extraction process.