Patent attributes
A particulate filtration device comprising filter media having upstream and downstream surfaces, a gas-moving device for moving gas through the filter media from the upstream surface toward the downstream surface, and a cleaning assembly including a blow pipe having a plurality of cleaning nozzles for directing a flow of cleaning gas toward the filter media. A first one of the cleaning nozzles comprises a structural characteristic (e.g., throat size, exit angle, exit size) that is different than a second one of the cleaning nozzles. In one embodiment, the filter media comprises a filter bag corresponding with each nozzle, and both the first one and the second one of the cleaning nozzles are spaced substantially the same distance from the corresponding filter bag. The cleaning assembly can also include a plurality of blow pipes (e.g., each having a plurality of cleaning nozzles) coupled to a gas-pressurized manifold, and a valve positioned between the manifold and each blow pipe to control gas flowing from the manifold to the blow pipes. In this configuration, it is preferred that the nozzle nearer the manifold has a larger throat size, smaller exit angle, and larger exit size than the nozzle farther from the manifold.
