The Study of Heterogeneous Condensation of Water Vapor on Submicron Particles in Cooled Tube by Population Balance Model

Abstract

The removal of submicron particles is becoming extremely important due to increasing serious air pollution in recent years. Heterogeneous condensation, as the prospective preconditioning technique, was paid more attention for its operability. This work is mainly to investigate the process of the heterogeneous condensation of water vapor in cooled tapered tube. The supersaturation environment of heterogeneous condensation was achieved by cooling the wall temperature of the tube. The Eulerian-Eulerian two-fluid approach was used to calculate the trajectory of the fluid in this physical model. The population balance model was used to simulate the growth process of particles in the flow field. It was found that the environment of particle enlargement was established when the temperature of the flue gas lower than the temperature of the wall surface. Particle growth was favoured by increasing residence time in cooled tube. When the initial concentration of particles is high, particles enlargement would be decreased due to insufficient water vapor under the same degree of supersaturation.