Evaluation of Suitable Material Properties of Sludge for Electroosmotic Dewatering

To estimate suitable material properties of sludge for electroosmotic dewatering, we experimentally measured the electrical and physical properties of a sludge bed. The use of an upper electrode that had a smaller area than the cross-sectional area of the bed was also investigated with the aim of reducing the electrical contact resistance between the electrode and the bed caused by dewatering. We found that sludge with a lower specific electrical resistance and a higher hydrodynamic compressibility in cake filtration provided greater electroosmotic dewatering performance. However, such a sludge was not necessarily available for using a smaller-area upper electrode.