Rotating membrane filtration and rotating reverse osmosis

Rotating membrane filtration is a means of dynamic filtration that incorporates both high shear and flow instabilities to reduce membrane fouling. The device consists of a cylindrical membrane filter rotating within an outer cylindrical shell. The superior performance of rotating membrane filtration appears to be a consequence of the high shear in the annulus, which is enhanced by the redistribution of azimuthal momentum by the appearance of Taylor vortices in the annulus. The anti-fouling characteristics of rotating filtration can be utilized for reverse osmosis in addition to microfiltration. In this paper, we review the physics underlying rotating filtration, examine the anti-fouling mechanisms in rotating filtration, and describe recent efforts to apply rotating filtration to reverse osmosis.