Treatment of olive oil mill waste water and its incorporation in building bricks - Optimization of their physico-mechanical properties by statistical analysis of principal components

The study of physico-mechanical properties of building bricks when water is substituted by olive oil mill waste water showed the effect of organic matter included in the effluent on the characteristics of the material. In fact, the incorporation of relatively high quantities of this effluent would deteriorate the mechanical characteristics of the bricks. In this study, a statistical approach using a principal components analysis confirmed the fact that the high concentration of organic matter included while using waste water or olive oil solid residue, had a negative impact on bricks properties which would be altered. In order to improve the properties of the material and to reduce the content of organic matter, the effluent was treated by a physico-chemical process based on coagulation then flocculation. Calcium hydroxide and ferrous sulphate were used as chemical reagents. The optimal elimination yield of 60%, expected in such treatments was achieved. It was noticed that this reduction in organic matter content would improve the physico-mechanical characteristics of bricks when water is replaced by treated waste water in building material processing.