Fluid mechanics of slurry flow through the grinding media in ball mills
- Univ. of Utah, Salt Lake City, UT (United States). Comminution Center
The slurry transport within the ball mill greatly influences the mill holdup, residence time, breakage rate, and hence the power draw and the particle size distribution of the mill product. However, residence-time distribution and holdup in industrial mills could not be predicted a priori. Indeed, it is impossible to determine the slurry loading in continuously operating mills by direct measurement, especially in industrial mills. In this paper, the slurry transport problem is solved using the principles of fluid mechanics. First, the motion of the ball charge and its expansion are predicted by a technique called discrete element method. Then the slurry flow through the porous ball charge is tackled with a fluid-flow technique called the marker and cell method. This may be the only numerical technique capable of tracking the slurry free surface as it fluctuates with the motion of the ball charge. The result is a prediction of the slurry profile in both the radial and axial directions. Hence, it leads to the detailed description of slurry mass and ball charge within the mill. The model predictions are verified with pilot-scale experimental work. This novel approach based on the physics of fluid flow is devoid of any empiricism. It is shown that the holdup of industrial mills at a given feed percent solids can be predicted successfully.
- OSTI ID:
- 276693
- Report Number(s):
- CONF-9510120-; ISBN 0-87335-139-8; TRN: IM9636%%404
- Resource Relation:
- Conference: 19. international mineral processing congress, San Francisco, CA (United States), 22-27 Oct 1995; Other Information: PBD: 1995; Related Information: Is Part Of Proceedings of the 19. international mineral processing congress: Comminution and simulation and control. Volume 1; PB: 326 p.
- Country of Publication:
- United States
- Language:
- English
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