GB671569A - Improvements in apparatus for disintegrating and screening particulate material - Google Patents

Abstract

671,569. Impact pulverizers. TYLER, G. M. Feb. 16, 1950, No..3990/50. Class 59 In disintegrating and screening apparatus of the type disclosed in Specification 477,183, the material is fed by the beaters onto two or more screens or screening sections having different degrees of fineness of mesh so that it is separated into two or more materials of different degrees of fineness of granule. As shown in Fig. 1 the apparatus comprises a hopper or casing 8 within which is supported an outer fine-mesh screen 16 and an inner coarse mesh screen 6 both screens being of inverted pyramidal form. The hopper has an outlet 9 for dust-like material, the outer screen has an outlet 17, and the inner screen has an outlet 7. Material to be treated is fed from'the feed hopper 15 on to rotatable beaters 3, 4 from whence the broken particles are thrown on to screen 6. Lumps which do not pass this screen leave by the outlet 7 and may be returned direct to the mill. Material not passing through the screen 16 is the required product whilst the fines passing through the screen are treated with water or steam jets 20, heaped for agglomerization and then returned to the mill. In the embodiment shown in Fig. 3 coarse lumps rejected by screen 6 are allowed to drop on to further beaters 41 all material which will not pass through the upper or lower portions of the screen 16 being then assumed to have the required granule size. If a hardened spherical form of granule is desired the material discharged from outlet 17 may be rotated in a separate drum which during rotation is subjected to external heat.