Gravity-Powered Chemical Dose Controller for Sustainable, Municipal-Scale Drinking Water Treatment
Publication: Journal of Environmental Engineering
Volume 139, Issue 8
Abstract
Accurate chemical dosing in water treatment plants is imperative to ensure optimal efficiency of flocculation and disinfection. Design algorithms, calibration techniques, and standardized components are presented for a linear flow orifice meter (LFOM) and a linear chemical dose controller (LCDC). These coupled systems allow water treatment plant operators to easily and reliably set and maintain the desired doses of coagulant and disinfectant. The combined system adjusts the chemical flow rate automatically in response to changes in plant flow rate to maintain the target chemical dose. The LFOM maintains a linear relationship between height of water in the entrance tank and plant flow rate. A lever and float are used to create a direct relationship between the plant flow and chemical flow produced by the LCDC. A linear relationship between head loss and chemical flow in the LCDC is created by using the major head loss through a small diameter tube to control the chemical flow rate. Experimental tests are described that minimize minor losses and verify performance of the LCDC.
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Acknowledgments
The research described in this paper was funded by the Sanjuan Foundation. This project was supported by a number of people at Cornell University, including Paul Charles, Timothy Brock, Alexander Krolick, Michael Adelman, and Dale Johnson. Special thanks go to Matthew Higgins, Jordanna Kendrot, and David Railsback for their work on early prototypes of the LFOM and LCDC.
References
Bache, D., and Gregory, R. (2007). Flocs in water treatment, IWA, London.
Brikke, F., and Bredero, M. (2003). “Linking technology choice with operation and maintenance in the context of community water supply and sanitation: A reference document for planners and project staff.” Technical Rep., World Health Organization and IRC Water and Sanitation Centre.
Franz, D. D., and Melching, C. S. (1997). “Full equations utilities (fequtl) model for the approximation of hydraulic characteristics of open channels and control structures during unsteady flow.”, U.S. Geological Survey, Reston, VA.
Gurevich, R. A., Balmaev, B. G., Lainer, Y. A., and Yampurov, M. (2003). “Investigation of the density and viscosity of aluminum sulfate solutions.” Russ. J. Non-Ferrous Met., 6, 16–19.
Hendricks, D. W. (2009). Fundamentals of water treatment unit processes: Physical, chemical, and biological, Taylor and Francis.
Schulz, C. R., and Okun, D. A. (1984). Surface water treatment for communities in developing countries, Wiley, Great Britain.
Thandaveswara, B. S. (2012). “Proportional weirs.” Technical Rep., Indian Institute of Technology, Madras, India.
Weber-Shirk, M. L. (2009). “Gravity powered flow controllers for chlorine and alum dosing.” J. Water Supply Res. Technol. AQUA, 58(2), 147–152.
World Health Organization (WHO). (2011). “Fact sheets on environmental sanitation: Fact sheet 2.22- dosing hypochlorite solutions.” Technical Rep.
Information & Authors
Information
Published In
Journal of Environmental Engineering
Volume 139 • Issue 8 • August 2013
Pages: 1023 - 1034
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Jul 25, 2012
Accepted: Mar 14, 2013
Published online: Mar 16, 2013
Published in print: Aug 1, 2013
Discussion open until: Aug 16, 2013
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