Physicochemical characterization of olive oil mill wastewaters in the eastern region of Morocco

The aim of this study is to achieve a complete physicochemical characterization of the samples of the olive oil mill wastewaters collected from five different prefectures in eastern morocco (oujda,nador,berkane,taourirt and jerada),a comparative study was investigated with several oomw samples from three olive oil extraction processes (traditional,semi- modern and continuous) were compared. this research is one of the first studies investigating the physicochemical characterization of olive oil mill wastewaters oil mills crushing olives oujda area. the composition of oomw varies significantly for each mill. the results of the physicochemical analyzes showed that all the samples of olive oil mill wastewaters have an acidic ph,the average value is between (4.5 and 5.32); and the values of the conductivity are varied between: 23-41ms/cm for the (pp and cp3p) but for the (cp2p) are varied between: 13-25 ms/cm,this high conductivity due to the addition of the salt during storage before their crushing olives. the oomws are rich in organic matter. this last parameter is expressed as bod5 and cod. the average of the total bod5,cod,biodegradability,of samples varied with oil extraction processes,for the (pp): (bod5: 17-25 g o2/l; cod :108-120 g o2/l; biodegradability: 0.11-0.25); for the (cp3p): (bod5: 12.5-23 go2/l; cod :76-100; biodegradability: 0.16-0.23) and for the (cp2p): (bod5: 8.5-19 go2/l; cod :52-64 g o2/l; biodegradability: 0.16-0.23). and the samples are riche of the oxidizable matters ((cod+2bod5)/3),therefore,the connecting this industrial facility to a municipal sewer system is impossible; because,any connection of the units trituration olives can lead to dysfunctional treatment plant wastewater; but which poses a great problem for these units trituration effluents is non-biodegradable material: polyphenols and tannins,the values(the samples of oomw filtered) are varied: (polyphenols: 0.8-1.35 g/l and tannins :0.62-1.2 g/l) for the pp,for cp3p (polyphenols: 0.29-1.83 g/l and tannins :0.2-1.71 g/l),but for the (cp2p) are varied between (polyphenols: 0.24-0.67g/l and tannins :0.12-0.65 g/l). in this article,recent and older research studies for the physicochemical characterization of olive mill wastewaters performed by several authors were shown.