FILTER TYPE DUST COLLECTOR

PURPOSE:To improve shaking-down effect of a dust collector by providing filters used separately for collecting dust in air stream contg. large sized dust and air stream contg., small-sized dust separated by a classifier provided to a duct for introducing outdoor air contg. dust, and setting filtration rate and frequency of skaking down suited to each filter. CONSTITUTION:Outdoor air 23 contg. dust is introduced into a dust collector with a fan 3 through a duct 14. And formed to swirling air stream by the guide vanes 16 of a classifier 15. Groups of particles having large average particle size are diffused radially by the centrifugal force through a clearance 18 into a first collecting chamber 11, where it is filtered by a filter 5. Groups of particles having small average particle size are introduced into a collecting chamber 12, where it is filtered by a filter 6. If, for example, the ratio of the filtration speed of the filter 5 to 6 is set at 7:3, decrease of treated air amt. due to increase of powder load is small even if the filtration speed is increased because of the coarse particle size of collected particles of the filter 5. Since the filtration speed for the filter 6 is smaller than the usual filtration speed, deposition of particles to the filter surface is small. Even if the power load is increased, the amt. of air to be treated is small; therefore, time interval for shaking down for both filters can be set to large intervals.