Plate separators for dispersed liquid—liquid systems: Multiphase flow, droplet coalescence, separation performance and design

Abstract Plate separators are effective and often used apparatus for the separation of droplets from liquids, e.g. in the case of oil/water purification. The separation is accomplished by letting the droplets coalesce on inclined plates. Mathematical models for stratified two-phase flow between the plates of a plate separator, the droplet motion in this type of flow and the coalescence of single drops are derived and compared with experimental results obtained. The degree of separation was measured and evaluated, and a design criterion was deduced. This allows the definition of hydrodynamically favourable operating conditions for the coalescence in plate separators. The required plate area can be computed on the basis of the operating parameters, whereby no information concerning the drop-size distribution is necessary.