Application of an electric field to enhance the flow of coal-water slurries in pipelines

Electrokinetics involves the movement of charged particles or water molecul es in an applied dc field. Applications in particle-fluid systems include t he dewatering of soils, the densification of mill tailings and the treatmen t of coal wastes. In this paper, a novel application of this technique is d iscussed, wherein an electric field is applied to a coal-water slurry flowi ng through a pipe, resulting in lower pressure losses in the system. A uniq ue experimental setup was designed and built to study the effect of an elec tric field (dc) on the wall shear stress for the flow of coal-water slurry through the pipe. The effect of solids concentration, current strength and pH on drag reduction across the system was quantified.