GB891435A - Improvements in apparatus for drying tobacco or similar materials - Google Patents

Abstract

891,435. Drying apparatus. ARENCO A.B. March 1, 1960 [March 20, 1959; Jan. 29, 1960], No. 7289/60. Class 34(2) Apparatus for drying tobacco or similar material comprises an upright cylindrical drum 1, Figs. 1, 2 and 3, having an inlet 3 for the material, an outlet 5 for drying air and a bottom which has an air pervious sector 15 defining a drying zone I in the drum, an outlet 18 for the dried material defining a discharge zone III in the drum and a solid sector 14 defining a trap zone IV in the drum; a central tube 6, an inlet 4 provided with a heating element and fan 11, for supplying drying air through the zone I; an impeller having a central tube 7 concentric with the tube 6 and provided with radial vanes 8, Fig. 3, projecting into the zones; and a motor 17 and chain 6 for rotating the impeller in the direction shown, i.e. so that the vanes sweep the zones I, III, and IV, in that order. The tube 7 is supported by a roller bearing 9 on the tube 6. The bottom of the drum is also provided with another perforated sector 21 defining a cooling zone II within the drum and a chamber below this sector houses a fan for sucking in air through openings in the drum wall and thereafter passing the unheated air through a valve and the sector 21 and thence through the material to finally emerge through a screen 20 to the outlet 5, together with the hot air from the zone 1. Some of this cool air will be recirculated down the tube 6 and through the fan 11 for use in the drying zone. The trap zone IV and the spacing of the vanes 8 ensures that material cannot reach the discharge zone from the drying zone in the direction reverse to the arrow; the inlet 3 is actually behind the inlet 4 and outlet 5, Fig. 1. An adjustable valve 13 is provided in the hot air chamber 12 below the sector 15 of the drum and the vanes 8 are provided with flexible seating strips 19.