DESIGN AND CHARACTERIZATION OF A DIGITAL-CONTROL SYSTEM FOR THE FLOW-THROUGH A MICROPOROUS MEMBRANE

In many scientific and industrial applications the permeating flow thr ough a membrane separating two fluid phases must be kept constant, eit her because the flow is feeding another system which requires a consta nt in-flow, or because membrane fouling is being studied and it is nec essary to know what must be done to maintain the flow. We describe a d igital proportional-integral controller which makes it possible to mai ntain a constant permeating flow through a Nuclepore membrane with 8 m u m mean pore radius. (C) 1996 American Institute of Physics.