Method for electrostatic removal of particulate from a gas stream

摘要

A method is disclosed for removing particulate matter from a gas stream. The method includes a packed wet scrubber through which a scrubbing liquid such as water is flowed vertically downwardly and through which gas to be cleaned is flowed in a direction transverse to the direction of flow of the scrubbing liquid. The packing material is disposed in a chamber and the packing material and scrubbing liquid are maintained electrically neutral. A stream of gas to be treated is ionized prior to its flow through the wet scrubber to provide particles in the gas stream with an electrical charge of a given polarity, usually negative. Upon flow of the gas stream through the wet scrubber, the charged particles in the gas stream are carried into close proximity with and are attracted to the scrubbing liquid and/or packing elements as a result of attraction forces between the charged particles and the electrically neutral packing elements and liquid. Thus, the charged particles are removed from the gas stream and are carried from the scrubber to a discharge point by the scrubbing liquid. The particle laden gas is flowed through the wet scrubber at a velocity which is sufficiently low to provide for the attraction forces to overcome the velocity of a particle in the gas stream and the drag force of the gas stream on the particle so that the particle is removed from the gas stream as opposed to remaining entrained therein and flowing through the scrubber.