GB211148A - Methods of and apparatus for washing the fine categories or dust of coal - Google Patents

Abstract

211,148. Knapen, J. Feb. 8, 1924. Inclined-trough washing-apparatus; upwardcurrent-classifiers.-In a washer for small coal, an obstacle 3, Fig. 2, is placed in the channel 1 to impede the current and cause deposition of heavy impurities which pass on to and through a strainer 4, or through an adjustable opening 6, into a vessel 2, kept constantly filled with water, and through a tube 12, provided with a valve 13 preferably automatically operated by the weight of the materials, to a tank 18 provided with a strainer 19 and an elevator 17. A division wall 7 may be placed in the vessel 2 and part of the current therein deviated past a waterjet device 10, impurities passing through a screen 9. If the discharge of water through the tube 12 is undulv great, a float 15, carried by a piston 16 in a laterally-placed tube 14, enters the tube 12, consequent disturbance in the veesel 2 giving an indication to the operator. In a modification, the strainer 4 is replaced by two or more stepped strainers of variable length; while, in a further form, a current of water fed to the lower side of the vessel 2 from an overhead reservoir is led downwards by a division wall extending below the wall 7, causing eddy currents below these walls to assist the washing. In the form shown in Fig. 4, instead of an obstacle 3, the inclination of the channel is increased at the strainer 4; a current of water is fed to the vessel 2 from a reservoir 2.