Changes in underflow solid fraction and yield stress in paste thickeners by circulation

Hong Li; Ai-xiang Wu; Hong-Jiang Wang; Hui Chen; Liu-Hua Yang

doi:10.1007/s12613-020-2184-z

Volume 28 Issue 3

Mar. 2021

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Article Navigation > International Journal of Minerals, Metallurgy and Materials > 2021 > 28(3): 349-357

Hong Li, Ai-xiang Wu, Hong-Jiang Wang, Hui Chen, and Liu-Hua Yang, Changes in underflow solid fraction and yield stress in paste thickeners by circulation, Int. J. Miner. Metall. Mater., 28(2021), No. 3, pp. 349-357. https://doi.org/10.1007/s12613-020-2184-z

Cite this article as:

Hong Li, Ai-xiang Wu, Hong-Jiang Wang, Hui Chen, and Liu-Hua Yang, Changes in underflow solid fraction and yield stress in paste thickeners by circulation, Int. J. Miner. Metall. Mater., 28(2021), No. 3, pp. 349-357. https://doi.org/10.1007/s12613-020-2184-z

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Research Article

Changes in underflow solid fraction and yield stress in paste thickeners by circulation

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Corresponding author:
Ai-xiang Wu E-mail: wuaixiang@126.com
Received: 12 November 2019; Revised: 1 September 2020; Accepted: 2 September 2020; Available online: 3 September 2020

Abstract

Abstract

The trouble-free and efficient operation of paste thickeners requires an optimal design and the cooperation of each component. When underflow discharging is suspended, alleviating the vast torque that the remaining solids within the thickeners may place on rakes mainly lies in the circulation unit. The mechanism of this unit was analyzed, and a mathematical model was developed to describe the changes in underflow solid content and yield stress. The key parameters of the circulation unit, namely, the height and flow rate, were varied to test its performance in the experiments with a self-designed laboratorial thickening system. Results show that the circulation unit is valid in reducing underflow solid fraction and yield stress to a reasonable extent, and the model could be used to describe its efficiency at different heights and flow rates. A suitable design and application of the circulation unit contributes to a cost-effective operation of paste thickeners.
- paste thickener;
- circulation unit;
- solids content;
- yield stress;
- rake failure

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