On the Dynamics of Electrostatically Precipitated Fly Ash

Abstract

One of the factors influencing the efficiency of modern electrostatic precipitators is the proper cleaning of dust collecting plates, which is usually done by a periodic rapping. The rapping blow excites the plates, which in turn dislodge the accumulated dust layer. The paper analyzes the response of a deposited dust layer to an arbitrary out-of-plane motion of the plate to which it is held by the action of molecular and electrostatic adhesive forces. A simplified one-dimensional model of the precipitated dust-layer is assumed to have viscoelastic properties of the Kelvin solid. The results indicate that—in addition to the acceleration level—the frequency of excitation as well as the adhesive-force arrangement are decisive in defining how and when the dust layer will break off the plate.