Patent GB-1455579-A (GB)
Title: Upstream classifier for a multi-separator
IPC: B04C5/02
Filed: 1973-12-13
Abstract: 1455579 Pneumatic separation; cyclone separators COMBUSTION ENG INC 13 Dec 1973 [15 Dec 1972] 57867/73 Headings B2H and B2P  Fine and coarse solid particles entrained in a fluid flowing througn a duct for delivery to separate receptacles are separated from each other by concentrating the combined fine and coarse particles in one region of the duct as a continuous, moving sheet of material; dediacting the sheet of material and the flowing fluid towards another region of the duct by impingement upon a baffle plate transversely inclined to the longitudinal axis of the duct; dividing the flowing fluid into separate streams; and passing one of the fluid streams in transverse relation to the sheet of material whereby the fine particles are removed therefrom for delivery with that fluid stream to one of the receptacles while the coarse particles and the other fluid stream pass through the other region of the duct for delivery to the other receptacle. In a flash drying system, at mixture of hot gas and entrained solid particles flows through a rectangular duct consisting of an upstanding section 28, a bend section 30 and a distribution section 32. The interior of the section 32 is provided with a pivotable baffle plate 40 which may be connected for simultaneous adjustment with a second baffle plate 42. The plates are fixedly attached to pivot pins supported in bearing pads 48 and are adjustably positioned by means of levers 50, 52 secured to the pivot pins and interconnected by an operating limb 54. The lever 52 carries an adjustment stud 58 for engagement in a selected recess in an index plate 56. The duct section 32 is connected with rectangular tangential inlets 24, 26 of cyclone separators 12, 14 which have particle discharge conduits 16, 18 and gas discharge conduits 20 provided with gas flow regulating dampers 22. In operation, the dampers 22 are adjusted so that the gas flow entering each separator is approximately the same. The baffle plates 40, 42 are moved to the position indicated in Fig. 4. As the stream of gas and entrained particles pass through the duct bend section 30, the particles are caused to migrate under the influence of centrifugal forces toward the radially outer boundary of the section with the fine particles arranged radially inwardly of the coarse particles. As the strea mleaves the bend section 30, it engages the baffle plate 40 which deflects the gas and sheet of particulate material towards the inlet 26 of separator 14. The portion of the gas flow which is to enter the inlet 24 of the separator 12 is diverted around around the free end of the baffle plate 40 and passes transversely through the sheet of particulate material thereby entraining with it the drier fine particles which are separated as finished product from the gas in the separator 12. The coarse particles pass with the rest of the gas flow into the separator 14 and after separation are returned to the drying system for further exposure to the hot gas. At the end of an operation, in order to flush the system of panticulate matter the admission of solids to the duct is halted while continuing the flow of gas there through. The baffle plates 40, 42 are pivoted so that the plate 42 points upwardly in the direction of the separator inlet 24 whereby all the particles remaining in the system pass with the part of the gas flow into the separator 12 where they are finally separated.