MODELING OF VENTURI SCRUBBER PERFORMANCE

The performance of the Brink and Contant industrial-size Venturi scrub ber has been successfully simulated by means of a two-dimensional comp uter model. The two-phase, two-component, annular flow occurring in th e unit was predicted using a Particle-In-Cell (PIG) numerical techniqu e. Consideration of four different dust diameters, ranging from 0.5 to 10 mu m, allowed evaluation of the Venturi grade efficiency curve. Li quid jet penetration and drop size distributions, incorporated as impo rtant parameters, were linked to significant liquid maldistribution in the Venturi throat. This study confirmed the observation that the dro ps are actually classified by inertial effects which enable bigger dro ps to penetrate further into the central core of the air stream and th e smaller drops to stay closer to the duct walls. As a result, the sma ller drops were not observed in the region occupied by the larger drop s. This liquid maldistribution persisted throughout the scrubber and r esulted in predictions of particulate collection efficiency that were lower than would be expected with the usual assumption of uniformly di stributed drops of one size using one-dimensional models. Because this two-dimensional model can incorporate different liquid injection mode s and drop size distributions, it provides considerable versatility fo r the simulation of cleaning processes in Venturi scrubbers.