Method and appliance for dedusting the precipitation electrode plates in a dry electrostatic dust filter

摘要

Such a method for dedusting the precipitation electrode plates is implemented by generating vibrations in the precipitation electrode plates in a mechanical way, i.e. by tapping. In this context, a distinction is made in turn between longitudinal tapping and transverse tapping of the precipitation electrode plates. In the case of longitudinal tapping, the precipitation electrode plates (2) are guided in tapping rods. They can move in their own longitudinal direction, however, so that they can expand under the temperature influence of the hot gas to be dust-freed. The tapping rod transmits the impact to the plate which is thereby excited into a vibration, so that the dust drops off it. In the case of transverse tapping, the plate is made to vibrate in the transverse direction. It has been found to be a drawback that the precipitation electrode plates (2) tend to buckle when exposed to non-uniform temperatures, as a result of which free expansion in the longitudinal direction of the plates is no longer possible. The generation of vibrations by means of tapping appliances on the basis of longitudinal tapping or transverse tapping therefore does not result in satisfactory vibrations which cause all of the dust to drop off. A method for dedusting the precipitation electrode plates (2) is provided, in which the pendulous precipitation electrode plates (2) have gas jets (12) directed against them in the form of pulses up to an intensity causing striking against a pendulum limit stop (4). The dedusting appliance for implementing the method is arranged in such a way that the rows (1) of precipitation electrode plates (2) are each suspended between the pendulum limit stops (4), which maintain a gap (7, 8) of from 2 to 20 mm, and that nozzles (10) for generating the gas jets are provided. IMAGE