Design Framework for Electrokinetically Enhanced Dewatering of Sludge
Publication: Journal of Environmental Engineering
Volume 136, Issue 4
Abstract
Electrokinetic (EK) dewatering involves the application of a (direct current) voltage across sewage sludge, driving water under an electrical gradient from the positive electrode (anode) to the negative electrode (cathode). Researchers have shown the technique to be efficient means of driving off water from the sludge, thus improving strength and reducing volume. This paper presents an integrating framework for EK dewatering under constant voltage and constant current conditions, founded on the mathematics of simple electrical circuits and demonstrated by laboratory experimentation. The derived equations and experimental results showed that electroosmotic flow rate decreases with time when dewatering with constant voltage and is constant when constant current conditions are maintained. Having a linear relationship between flow and time, EK dewatering with constant current not only enhances the sludge dewatering efficiency, but also has the advantage of simplifying design procedures.
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Information & Authors
Information
Published In
Journal of Environmental Engineering
Volume 136 • Issue 4 • April 2010
Pages: 417 - 426
Copyright
© 2010 ASCE.
History
Received: Aug 13, 2009
Accepted: Sep 11, 2009
Published online: Sep 14, 2009
Published in print: Apr 2010
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