PRESSURIZED ELECTROOSMOTIC DEWATERING IN A FILTER CYCLE*

Abstract

This paper describes the role of pressurized electroosmotic dewatering (EOD) in a filter cycle. A laboratory-scale filter-press was used to filter a highly conductive silica suspension under constant pressure, followed by washing and mechanical precompression of the filter cake and finally by pressurized EOD at constant electric current. The influence of filter cycle parameters (filtration and washing pressure and duration, mechanical pressure, and electric field intensity) on the final cake dryness and energy consumption was studied. Electrodes of different materials, forms, and surfaces were used. The optimal conditions of each filter cycle operation were found to minimize the energy consumption during EOD and maximize the cake dryness. With mechanical pressure and electric field intensity increasing, the total energy consumption increased, but the specific energy consumption (per kg of expressed water) decreased, and the final filter cake was dryer. The pressurized EOD also used less energy than thermal drying.

*This article was published with incorrect figures in Drying Technology, 19(1), pp. 185–198. The complete article with correct figures is reprinted here.

Keywords:

• Dewatering
• Electroosmosis
• Filter cycle
• Filter-press
• Silica suspension

Acknowledgments

Notes

*This article was published with incorrect figures in Drying Technology, 19(1), pp. 185–198. The complete article with correct figures is reprinted here.