Druck-Siebvorrichtung zur Siebklassierung von teilchenfoermigem Material

摘要

A method and apparatus for increasing the sifting capacity of a pressurized oscillating sifter by directing upwardly a portion of the pressurized air conveying particulate material through a by-pass screen of the same mesh as the sifting screen and into a by-pass channel. The by-pass air is then utilized to entrain the undersize materials which passed through the screen (also called "under," "thrus" and "fines") and convey it to further processing stations. Bed depth on the top screen may be increased by providing a weir at the outlet for oversize material (also called "overs" and "tailings"). Carryover of high-velocity fines into the overs is prevented by providing an impact barrier at the overs outlet on the last screen.