GB1462038A - Dust extraction apparatus - Google Patents

Abstract

1462038 Sieving apparatus A F WHINFREY 12 Feb 1974 [15 Feb 1973] 7577/73 Heading B2H An apparatus for extracting dust from material, e.g. coal, comprises an extraction chamber 10, Fig. 1, at least a part of the floor 12 of which is provided with a plurality of holes 14 or slots through which dust and small fractions of material can fall into a collecting box 16; a water sprayer 18 for damping down the dust in the chamber 10; and hinged doors 22, 24 at opposite ends of the chamber for reducing the escape of dust from the chamber the dobrs hanging down freely and being opened by 'the material entering and leaving the chamber. A further sprayer may be provided at 20 in the collecting box. One or more paddle elements 26, Fig. 1, mounted on a rotatably driven shaft 28 are provided in the extraction chamber 10 to assist the flow of material and/or for tumbling the material. In Fig. 4, the paddle elements 36 are mounted in staggered relation on at least one freely rotatable shaft 34 disposed across the collecting box 16 and extend through slots 38 in the floor of the extraction chamber, the coal passing through the chamber causing the paddle elements to rotate. The apparatus is mounted on skids 32 so that it can be moved together with coal conveyor means as mining progresses. Alternatively it may be mounted on a coal cutting machine for movement along a coal face. In a modification the apparatus is provided with scraper chain belt within the collecting box so that collected dust and small fractions of coal, in the form of slurry, can be fed, for example, to a furnace for combustion. The extraction apparatus may be used in conjunction with a dust damping apparatus, Fig. 5, comprising a chamber having a floor to which one or more humped metal plates 42 are connected at their upstream ends, the downstream ends' of the plates being spaced from the floor so that water spray ducts 44 installed under the plates are arranged to direct sprays of water beneath material as the latter is jolted over the humps provided by the plates whilst being dragged along the floor by a scraper chain conveyor 46, 48 so that dust and small fractions of material are shaken loose and are wetted by the sprays.