Optimizing oxidized coal flotation using impact flow conditioning pulp

ABSTRACT

Numerous oxygen elements are present on the oxidized coal surfaces, resulting in the difficulties for flotation. In this study, the enhancement of oxidized coal flotation using the impact flow conditioning pulp was investigated, and the impact flow velocity was optimized. The enhancement mechanism of the impact flow conditioning pulp was investigated via a series of experiments. The results showed that the use of impact flow conditioning pulp could improve the cumulative combustible recovery and flotation kinetics of oxidized coal, and these increased with the increasing impact flow velocity. In the experimental range, an optimum flotation result was obtained at an impact flow velocity of 5 m/s. The SEM analysis showed that the impact flow conditioning pulp could remove the aggregations on the oxidized coal surface, exposing a fresh surface. The XPS analysis confirmed that the impact flow conditioning pulp could increase the carbon contents and decrease the oxygen contents on the oxidized coal surface. Further, the impact flow conditioning pulp could significantly enhance the hydrophobicity and floatability of oxidized coal.

KEYWORDS:

• Oxidized coal
• flotation
• impact flow
• pulp conditioning
• oxygen containing functional group

Acknowledgments

This work had received the financial support from the National Natural Science Foundation of China (No. 51722405, No. 51974310) and the National Key Research and Development Project (Grant No. 2019YFC1904301), and all authors express their sincere thanks for them.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [No. 51722405, No. 51974310]; National Key Research and Development Project [2019YFC1904301].