Numerical evaluation of optimal approaches for electro-osmosis dewatering

ABSTRACT

A newly developed numerical model is used to identify and evaluate optimum electrode configurations for electro-osmosis dewatering, as well as to evaluate approaches such as current intermittence and current reversal. Various electrode configurations, electrode spacings, and voltage gradients are studied numerically using 3D models with a cubic domain and vertically installed tube electrodes. The results indicate that, with more anodes installed, one can expect more water to drain out and a more uniform surface settlement, although a greater energy consumption is then required. A 2D square domain is used to study current intermittence and current reversal. Current intermittence allows more water to be drained out and has a higher energy efficiency compared to a continuous current, although it consumes more energy. Polarity reversal is also shown to be more efficient than a continuous current supply.

KEYWORDS:

• Current intermittence and reversal
• electro-osmosis dewatering
• electrode configuration
• energy consumption
• numerical modeling

Acknowledgments

The authors are grateful to the open research fund of the State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences (Grant No. Z01004), the China Scholarship Council, and the Geo-Engineering Section of Delft University of Technology for financial support of the first author.