Optimization of conventional treatment of the surface water treatment plant of the city of Khenifra

Abstract

Treatment of the surface water of the city of Khenifra combines a conventional treatment and a membrane process unit (reverse osmosis). The conventional treatment in question uses an aluminium base reagentin the form of Aluminum sulphate that may cause leaks of Aluminum called "residual Aluminum" in the filtered water. The objective of this work is to study the elimination of residual aluminum, resulting from the conventional treatment, for a better operation of the demineralization unit by Reverse Osmosis, located downstream. Indeed, according to the requirements of the supplier of the membranes, the residual aluminum content should not exceed 0.05mg/L. The jar test remains the most used test, at the level of the laboratories, which allows optimizing the doses of treatment reagents to be used in a treatment plant; particularly the aluminum sulfate coagulant. Trials of the jar test were performed and had been optimized by the application of Doehlert experimental design.

The effectiveness of the treatment and the optimum conditions through the stages of treatment are achieved by monitoring the parameters: pH, turbidity and residual aluminum.