GB346783A - Improvements in, or relating to, the drying of minerals and other substances - Google Patents

Abstract

346,783. Drying coal etc.; conveyers. SMITH, C. M., Garden House, Cornwall Gardens, South Kensington, London. Jan. 17, 1930, No. 1751. [Class 34 (ii).] Coal &c. is dried whilst being elevated by an endless conveyer o, Fig. 1, within a vertical shaft a which has a central partition f and is heated by hot gases (e.g. exhaust gases from a boiler flue) introduced through two apertures g. The material is fed by a rotary valve c and shoot e on to trays or buckets p carried by the endless chains, and is discharged by an outlet h to a bunker l. A fan may assist in drawing off the gases at i, a dust catcher k collecting any fines carried off by the gases and passing them to the bunker l. The trays p carried in bearings r are staggered, as shown in Fig. 5, alternate trays only facing the feed inlet. Charges are carried only by alternate trays, the trays in their upward movement being tilted as often as desired, to spill their contents each into the hotter and drier tray next below. For this purpose, the trunnions of the trays carry rollers 12, Fig. 3, on arms 11, these rollers being guided in vertical channels 13, 14 provided at intervals with cam-surfaces 22, 23. These cam-surfaces may be rendered effective or ineffective in pairs, according to the wetness, temperature, or speed, by means of pivoted tongues 28 operated by hand-levers 25. The cam-surfaces may be irregular, as shown in Fig. 7, to impart an initial shaking movement to the trays when tilting. The trays are of substantial thickness so that the heat taken up when descending may accelerate the drying action.