Patent ID: 7252253
Filing Date: 2007-08-07
Classification: B02C

Abstract:
1. A bowl mill for a coal pulverizer with an air mill for primary entry of air, comprising a substantially closed separator body ( 2 ) having a central axis; a bowl-like grinding table ( 3 ) mounted on a shaft ( 4 ) rotatable about said central axis, cooperating with a plurality of grinding rolls ( 6 ); and an air mill with an outer wall disposed under the bowl-like grinding table characterized in that said air mill is provided with multiple entry annular openings on the outer wall of said air mill, resulting in better uniformity in air flow around the air mill section and minimizing formation of eddies and vortices, and further comprises an inlet ( 19 ) which is bifurcated with a partition ( 28 ) allowing half of a primary air entering inlet ( 19 ) to enter the air mill through a first opening ( 21 ) and the other half of the primary air entering inlet ( 19 ) to enter a duct ( 23 ) leading to a second opening ( 25 ) which is set 180 degrees from the first opening ( 21 ) whereby the partition splits entry of the primary air into the air mill into two streams of air.