GB428698A - Improvements in or relating to the drying of grass and apparatus therefor - Google Patents

Abstract

428,698. Treating grain; storing crops; haymaking. CAREY, W. F., and SLADE, R. E., Norton Hall, The Green, Norton-on- Tees, and IMPERIAL CHEMICAL INDUSTRIES, Ltd., Millbank, London. Nov. 17, 1933, Nos. 32079/33 and 8114/34. [Classes 5 (i), 6 (iii), and 58] [See also Group XIII] Grass and other crops such as clover, lucerne, potatoes, grain, are dried by passing hot gases through a bed of the material in two or more stages of successively increasing temperature, the stages being separated by intervals in which the material is not exposed to the hot gases but is tedded or otherwise treated to expose undried aggregations to the effect of the gases in the following stage. The gases in the hotter stage of a two-stage process may be at 140-180‹ C., and in the cooler stage at 100‹ C., the cooler stage being ended when the temperature of the exit gases rises to about 80‹ C. In the form shown, the grass, loaded on to trays having bottoms formed of parallel wires, is run over racks on to ledges 23 which support the trays individually in the drying chamber. A fan in the space 9 draws hot gases from a coke furnace 6 through the material. The temperature of the gases is controlled through dampers 13, 14. Sparks are arrested and the gases mixed by the perforated cover 15 and baffles 16 and 17. A baffle 18 deflects the gas stream on to the trays. The fan may be driven from the engine which drives a baling press 12, such as that described in Specification 327,409, [Class 5 (i)]. The gas velocity through the material may be 2À5 ft. per second. While one pair of trays is in the drying chamber another pair is being loaded, the lower tray with partly dried grass from the upper tray and the upper tray with wet grass. A tight seal with the walls of the drying chamber is ensured by hinged cheeks on the feed-racks to the chamber which compress the grass and by bosses on the swing doors of the drying chamber.