Modeling and Measurement of Electrostatic Spray Behavior in a Rectangular Throat of Pease-Anthony Venturi Scrubber

Abstract

This paper presents the simulation and experimental results of the distribution of droplets produced by electrostatic nozzles inside a venturi scrubber. The simulation model takes into account initial liquid momentum, hydrodynamic, gravitational and electric forces, and eddy diffusion. The velocity and concentration profile of charged droplets injected from an electrostatic nozzle in the scrubber under the combined influence of hydrodynamic and electric fields were simulated. The effects of operating parameters, such as gas velocity, diameter of the scrubbing droplets, charge-to-mass ratio, and liquid-to-gas ratio on the distribution of the water droplets within the scrubber, were also investigated. The flux distribution of scrubbing liquid in the presence of electric field is improved considerably over a conventional venturi scrubber, and the effect increases with the increase in charge-to-mass ratio. Improved flux distribution using charged droplets increases the calculated overall collection efficiency of the submicron particles. However, the effect of an electric field on the droplet distribution pattern for small drop sizes in strong hydrodynamic field conditions is negligible. Simulated results are in good agreement with the experimental data obtained in the laboratory.

Characteristics of particles deposited on a single free-fall charged droplet

“…For opposite-polarity, charged-droplets and charged-particles WES, particles deposit onto the droplet due to electrostatic attraction forces. Many studies, including numerical simulations (Pilat et al 1974;Wang et al 1986;Jaworek et al 1997Jaworek et al , 2002Kojevnikova and Zimmels 2000;Yang et al 2003;Zhao and Zheng 2008;Carotenuto et al 2010) and experimental tests (Kraemer and Johnstone 1955;Balachandran et al 2003;Jaworek et al 2006b;Krupa et al 2013), suggest that droplet-target deposition of the particles is more effective. One important reason is that the distances of deposition from particles to droplets are much closer than to chamber walls, closer distance in turn strengthens the electrostatic attractions.…”