American Journal of Civil Engineering
Volume 4, Issue 5, September 2016, Pages: 205-215
Received: Jul. 14, 2016;
Published: Jul. 15, 2016
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Frederick W. Pontius, Department of Civil Engineering, California Baptist University, Riverside, California, USA
Inorganic aluminum or iron salts have been used for many decades to coagulate colloidal particles in surface water prior to flocculation, sedimentation and/or filtration. Although effective, inorganic coagulants have several disadvantages including large chemical dosages required for treating eutrophic waters, large volumes of chemical sludge produced, and toxic effects of metallic coagulants on the aquatic environment. Chitosan is a natural cellulose-like copolymer of glucosamine and N-acetyl-glucosamine. Because of their biodegradability chitosan-based materials have been suggested as a more eco-friendly coagulant for water and wastewater treatment. Chitosan was an effective coagulant in several prior laboratory studies. Practical application of chitosan as a drinking water treatment coagulant is evaluated here through a series of jar tests. The effectiveness of chitosan is compared to aluminum sulphate and ferric chloride with regard to treatment of algal-ladened waters. The optimum chemical dose for coagulation, optimum pH, and effectiveness for algae removal was determined for each coagulant. Practical aspects of applying chitosan at full-scale and the impact of feeding this chemical on overall treated water quality are addressed.
Frederick W. Pontius,
Chitosan as a Drinking Water Treatment Coagulant, American Journal of Civil Engineering.
Vol. 4, No. 5,
2016, pp. 205-215.
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