JOURNAL PAPER

 

Investigation of factors influencing the attrition breakage of coal

 

 

V. Oberholzer; J. van der Walt

School of Chemical and Minerals Engineering, North West University

 

 

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SYNOPSIS

The presence of fines (particles smaller than 6 mm in diameter) causes hydrodynamic problems in gasifiers and therefore it is of great importance to minimize the amount of fine coal in the feed. This serves as motivation for understanding coal's breakage mechanisms, which could lead to the ability to predict the generation of fines.
The aim of this project was to simulate the pulsating effect of the conveyor belt in order to investigate factors influencing the breakage.
Results indicated that an increased initial particle size had an increasing effect in the amount of fines generated. Weathering had an insignificant effect on the breakage of coal. To conclude, a breakage model was developed to describe the rate of breakage out of the top size when a combination of two breakage modes is present.

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Paper written on project work carried out in partial fulfilment of B.Ing. (Chem. Eng.)