Scale Up from Small Oven-Drying Tests of Mineral Concentrate to Pilot-Scale Drying with a Heated Pad

Abstract

While Fickian diffusion models are commonly used in other applications, there are few reports of them being applied to the batch drying of a mineral concentrate. Diffusion coefficients estimated from small-scale oven-drying tests were used to predict the drying behavior of a concentrate sample 1 m × 1 m in area and 50 cm deep, with a heated bottom pad. These pilot-scale tests included both daily turning of the sample and turning every three days. The excellent quantitative agreement between the predicted and observed pilot-scale behavior gives a high level of confidence in the model predictions and suggests that a Fickian diffusion model is adequate to predict the behavior of mineral concentrates at the low moisture contents used here.

Keywords:

• Diffusion model
• Mineral concentrate
• Scale up

Acknowledgments

Thanks are due to Ms. B. Clarke of Pasminco Smelter Technical Support for carrying out the oven-drying tests and to Messrs J. A. Johnson and P. A. Merrigan of CSIRO Minerals for the conduct and reporting of the pilot-scale tests.