Abstract: In an electrostatic precipitator which is supplied with energy in the form of d.c. voltage pulses or of a d.c. voltage and superposed pulses, the energy supply is optimized and reverse corona discharges are avoided by use of a method in which energy at the highest possible rate is supplied to the electrostatic precipitator during the pulsing period and the total energy consumption of the electrostatic precipitator required to achieve in the pure gas a predetermined maximum dust content is minimized in that the pulse parameters are optimized and the application of pulses is interrupted for the longest possible non-pulsing time which is consistent with the predetermined maximum dust content of the pure gas.

Abstract: A control device for an electrostatic precipitator including a plurality of filter chambers connected in series to one another comprises a first component connected to a particle density sensor at the output of the last filter chamber for computing desired values of the particle densities at the outlets of the individual filter chambers in response to the difference between a desired particle density and a measured particle density of the outflowing gases at the output of the last filter chamber.

Abstract: For a dust-collecting plant, in which a plurality of gas streams are sucked from spaced apart dust sources and are delivered in a manifold to a dust-collecting unit and the gas is delivered by a controllable exhaust fan to an exhaust gas chimney, a method is provided wherein the automatic control and the operation of the plant are improved whereas the power requirement is minimized. A feedback control system having an individually adjustable desired value r.sub.i is associated with each gas source. An overriding feedback control system is provided for controlling the exhaust fan. The pressure drop R to be maintained by the exhaust fan is changed in dependence on the position of the final control elements associated with the several dust sources.

Abstract: A method for operationally determining the existence of an optimal rapping interval for the collector electrodes of an electrostatic precipitator comprises the comparison of the current-voltage characteristics for precipitator operation under pure-gas conditions and actual use conditions. If the comparison indicates that the resistance of accumulated dust layers is greater than the resistance of air, then an optimal rapping interval exists. This interval may be calculated analytically or approximated by means of an iterative process.