Correction of froth gray value in the prediction of clean coal ash content in coal flotation

ABSTRACT

The correlation between froth properties and the quality of the froth product is the key to predict flotation performance and improve the automatic control of flotation. It is known that froth gray value increases with the clean coal ash content and is often used in the prediction of coal flotation performance. But the accuracy of ash content prediction is usually unsatisfactory because the froth gray value can be easily interfered by the circumstance. In this study, the average gray value of the black experimental table was selected as the reference block to correct the froth gray value. The inaccurate froth gray value was corrected by the initial gray value and the gray value fluctuation of the reference block. The R² of the linear fitting between froth gray value and clean coal ash content increased from 0.64 to 0.93 after the correction. This work showed that the correction method can significantly improve the accuracy of flotation performance prediction by gray value.

KEYWORDS:

• Flotation
• gray value
• ash content
• prediction
• froth

Acknowledgments

This work was supported by “the Fundamental Research Funds for the Central Universities” (Project 2019QNA25). Jiakun also wants to thank Prof. Minqiang Fan in Taiyuan University of Technology for the discussion about gray value and brightness in Jiakun’s graduation defence.

Additional information

Funding

This work was supported by the Fundamental Research Funds for the Central Universities [2019QNA25].