Title: Optimal strategy for algae control in potable water treatment facilities

Authors: Nidal Hilal, Nick Hankins, Ik-Hawn Cho, Chang-Gyun Kim

Addresses: Centre for Clean Water Technologies, School of Chemical, Environmental and Mining Engineering, The University of Nottingham, University Park, Nottingham NG7 2RD, UK. ' Centre for Clean Water Technologies, School of Chemical, Environmental and Mining Engineering, The University of Nottingham, University Park, Nottingham NG7 2RD, UK. ' Water Quality Laboratory, Incheon Metropolitan City Waterworks, Republic of Korea. ' Department of Environmental and Civil Engineering, Inha University, Republic of Korea

Abstract: This paper presents both a current review of the state-of-the-art in algae removal, and an experimental study of algae removal in potable water supply. Established techniques were investigated by jar-testing on surface raw water samples derived from a lowland river, with the dominant species of algae being Scenedesmus sp (a green algae). These tests were conducted both in isolation and in combination to determine the optimum operational strategy for an actual water treatment facility. Employing 1 mg/L of Cu2SO4 could remove algae by up to 50.6%, though this might lead to the release of algal toxin. The most effective single technique was PAC addition, which could reduce the algae population by up to 97.6%, although doses above 30 mg/L created turbidity. The maximum reduction ratio achieved with polyaluminium chloride in the absence of pH control was 79.1%, employing a dosage of 14 mg/L; careful pH control during addition of poly-AlCl3 coagulant increased algae removal by up to 35%.

Keywords: algae removal; coagulation; drinking water; PAC dosing; potable water treatment; powdered activated carbon; prechlorination; water quality.

DOI: 10.1504/IJETM.2004.005584

International Journal of Environmental Technology and Management, 2004 Vol.4 No.3, pp.236 - 252

Published online: 21 Oct 2004 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article