Heterogeneous condensation of water vapor as a preconditioning technique for fine particle removal has been investigated experimentally and theoretically by several authors for decades [8–13]. The results of these investigations show that submicron
particles can be enlarged by heterogeneous condensation and efficiently separated from saturated warm gas streams. However, detail information about the influence of different parameters, such as initial particle concentration, temperature of flue gas, mass of condensable water vapor and initial size distribution on the activation and growth rate of fine particles were not given. In fact, this knowledge is necessary for the industrial application of this technique.