Experimental investigation of coal particle motion in a model of a beater wheel mill TES-2500/920 type

The paper presents particle-velocity measurements obtained with an one component fiber optic, back scatter laser Doppler anemometer in a model of a lignite beater wheel mill. The mill-model has been constructed with the aim to retain the same particle motion characteristics as in the mills used by the Mongolian Power Plant Company (P.P.C.) for the pulverization and drying of lignite and brown coal. An analysis of the particle motion characteristics and the adopted scaling down procedure for the design of the model mill, which retains geometrical and fluid dynamic similarity, are presented. The real and model beater wheel mills are described and the simplifications adopted are discussed. The experimental results shed light into the particle motion inside the mill and allowed to locate areas, where particles tend to accumulate and where erosion-wear is expected to be high.