Feasibility of Using Chitosan as a Flocculent in the Removal of Suspended Matter from Municipal Oxidation Pond Effluent and Gravel Pit-Washing Effluents

摘要

The objective of the project was to determine the feasibility of using chitosan as a flocculant for the removal of suspended matter from both oxidation pond effluent (including algae) and gravel pit-washing effluent. The study compared the performance of three grades of chitosan in removing this suspended matter to that of ferric chloride and aluminum sulfate, two inorganics commonly used for that purpose. The study concluded that flocculation of this suspended matter using chitosan is controlled by typical chemical reactives (e.g. temperature, pH, and concentration); the effective range for using chitosan is between pH 5.5 and 8.0; the optimum concentration for flocculation within the effective pH range is 10 ppm, irrespective of the grade of chitosan used; and that the physical/chemical boundaries within oxidation pond effluent and gravel pit washings do not restrict the use of chitosan either environmentally or economically.