Journal of Electrostatics, 19 (1987) 1--19 1 Elsevier Science Publishers B.V., Amsterdam -- Printed in The Netherlands ESTIMATION OF PARTICULATE CHARGING AND MIGRATION FOR PULSED PRECIPITATOR APPLICATIONS LEMBIT SALASOO, J. KEITH NELSON Rensselaer Polytechnic Institute, Center for Electric Power Engineeridg, Troy, NY 12180--3590 (U.S.A.) ROBERT J. SCHWAB'E and ROBERT W.L. SNADDON General Electric Company, Research and Development Center, P.O. Box 8, Schenectady, NY 12301 (U.S.A) (Received September 2, 1985; accepted in revised form May 24, 1986) Summary A simulation is described which permits the evaluation of dispersed particulate behaviour under the transient ion density and space-charge fields appropriate to the operation of electrostatic precipitators with pulsed energization. Field, field-assisted diffusion and pure diffusion charging mechanisms are used to describe the charging and a novel stochastic scheme is introduced to evaluate particle charge density distributions in both space and time when turbulent diffusion is important. Supporting experimental measurements are introduced to measure the particle charge distributions and to estimate the spatial changes in dust concentrations as a result of the migration processes within a precipitator. 1. Introduction and background The application of pulse energization to electrostatic precipitators (ESP's) can have substantial benefits when high resistivity particulate materials are involved. Some of the principles have been outlined by Petersen [1] from which it is evident that pulse precipitation is an attractive technology because it can, in principle, be retrofitted to upgrade an existing conventional precipitator facility. However, the prediction of performance under pulse energization is a complex procedure for which existing quasi steady state simulations [2] are quite inappropriate. The time varying nature of electric field due to both the applied voltage and space-charge movement has a pro- found effect on the generation of corona, which is clearly central to the operation of a precipitator. The modelling of this process has recently been undertaken by Salasoo et al. [3], allowing prediction of electric fields and ion densities as functions of time for cylindrical precipitator geometry. This present contribution extends that effort to examine the applications of pulse powering on the charging and migration of particulates for precipita- 0304-3886/87/$03.50 © 1987 Elsevier Science Publishers B.V.