CHITOSAN APPLICATION FOR TREATMENT OF BENI- AMRANE'S WATER DAM

摘要

Chitosan is a biopolymer, biodegradable, non-toxic and widely abundant in nature. Our study presents an investigation on the application of this biopolymer in treatment of Beni- Amrane dam water by coagulation flocculation process. In this study, the raw water from Beni-Amrane dam characterized by high turbidity was treated using chitosan as primary flocculant and as coagulant aid with aluminum sulfate (alum). The performance of this process was evaluated by measuring the supernatant residual turbidity for various values of chitosan concentrations. The obtained results are in favor of chitosan. With low concentrations, chitosane used alone is able to reducing 85% of initial turbidity. In the case of using chitosane in combination with alum, highest turbidity removal (97 %) was carried out with 0. 15 mg/l of chitosan and 20 mg/l after 45 minutes of settling time. At this value, a very low residual aluminum (0, 02 mg/l) was registered. The organic carbon contribution on the turbidity coagulation flocculation performance is negligible because chitosan is used in small doses. Hence, chitosan could be used as natural coagulant aid for drinking water treatment with lowest risks of organic release. These properties, combined with its non-toxicity, make the chitosan as the best substitute to conventional synthetic polyelectrolytes used so far.