Modeling of Venturi Scrubber Performance

Abstract

The performance of the Brink and Contant industrial-size Venturi scrubber has been successfully simulated by means of a two-dimensional computer model. The two-phase, two-component, annular flow occurring in the unit was predicted using a Particle-In-Cell (PIC) numerical technique. Consideration of four different dust diameters, ranging from 0.5 to 10 μm, allowed evaluation of the Venturi grade efficiency curve. Liquid jet penetration and drop size distributions, incorporated as important parameters, were linked to significant liquid maldistribution in the Venturi throat. This study confirmed the observation that the drops are actually classified by inertial effects which enable bigger drops to penetrate further into the central core of the air stream and the smaller drops to stay closer to the duct walls. As a result, the smaller drops were not observed in the region occupied by the larger drops. This liquid maldistribution persisted throughout the scrubber and resulted in predictions of particulate collection efficiency that were lower than would be expected with the usual assumption of uniformly distributed drops of one size using one-dimensional models. Because this two-dimensional model can incorporate different liquid injection modes and drop size distributions, it provides considerable versatility for the simulation of cleaning processes in Venturi scrubbers.