2760
A Study of Nanobubble Pre-Conditioning for
Enhanced Fine Particle Flotation
Bo Qiao, Huang Hao, Zhanglong Yu, Dongping Tao
School of Resources and Environmental Engineering,
Shandong University of Technology, Zibo, Shandong, China
Zhongxian Wua
School of Resources and Environmental Engineering,
Shandong University of Technology, Zibo, Shandong, China Key Laboratory of Coal Processing and Efficient Utilization
of Ministry of Education,
School of Chemical Engineering and Technology,
China University of Mining and Technology, Xuzhou, Jiangsu, China.
ABSTRACT: Most minerals are beneficiated with the process of froth flotation and efficient flotation performance
is essential for achieving a high recovery of precious mineral resources. However, fine particles are known to
be difficult to float due to its low probability of collision with conventional sized bubbles. Nanobubbles have
very unique surface and physicochemical characteristics and have been successfully applied to enhancing the
performance of fine particle flotation with a number of coal and minerals. In this study, experimental flotation
results with typical coal samples are presented to demonstrate the effect of nanobubbles on fine particle flotation
behavior and the controlling process parameters. The principal nanobubble enhancement mechanisms for pre-
conditioned fine coal particle flotation are discussed briefly.
Keywords: Coal Enhanced flotation Flotation column Minerals Nanobubbles
INTRODUCTION
For a long time, coal accounts for more than 60% of
China’s energy production and consumption, and it will
remain the pillar industry of China’s energy for quite a long
time to come. However, China’s coal quality is poor (Gui et
al. 2021), and low-rank coal accounts for about 40% of the
proven coal reserves (Gui et al. 2017a). With the increas-
ing degree of mechanization and deepening of coal mining
and the increasing proportion of low rank coal the amount
of fine and high ash coal particles is also increasing rapidly
(Gui et al. 2017b). Cleaning of fine and high ash coal is
proven difficult, particularly for low rank coal. Therefore,
the development of low-cost and high-efficiency flotation
process has become an important development direction of
the coal beneficiation industry, which plays a crucial role in
improving the utilization rate of coal resources and protect-
ing the ecological environment.
Flotation utilizes the difference in surface hydropho-
bicity of valuable and gangue minerals to realize their sepa-
ration during which hydrophobic minerals are captured by
bubbles and float up to the froth layer whereas hydrophilic
A Study of Nanobubble Pre-Conditioning for
Enhanced Fine Particle Flotation
Bo Qiao, Huang Hao, Zhanglong Yu, Dongping Tao
School of Resources and Environmental Engineering,
Shandong University of Technology, Zibo, Shandong, China
Zhongxian Wua
School of Resources and Environmental Engineering,
Shandong University of Technology, Zibo, Shandong, China Key Laboratory of Coal Processing and Efficient Utilization
of Ministry of Education,
School of Chemical Engineering and Technology,
China University of Mining and Technology, Xuzhou, Jiangsu, China.
ABSTRACT: Most minerals are beneficiated with the process of froth flotation and efficient flotation performance
is essential for achieving a high recovery of precious mineral resources. However, fine particles are known to
be difficult to float due to its low probability of collision with conventional sized bubbles. Nanobubbles have
very unique surface and physicochemical characteristics and have been successfully applied to enhancing the
performance of fine particle flotation with a number of coal and minerals. In this study, experimental flotation
results with typical coal samples are presented to demonstrate the effect of nanobubbles on fine particle flotation
behavior and the controlling process parameters. The principal nanobubble enhancement mechanisms for pre-
conditioned fine coal particle flotation are discussed briefly.
Keywords: Coal Enhanced flotation Flotation column Minerals Nanobubbles
INTRODUCTION
For a long time, coal accounts for more than 60% of
China’s energy production and consumption, and it will
remain the pillar industry of China’s energy for quite a long
time to come. However, China’s coal quality is poor (Gui et
al. 2021), and low-rank coal accounts for about 40% of the
proven coal reserves (Gui et al. 2017a). With the increas-
ing degree of mechanization and deepening of coal mining
and the increasing proportion of low rank coal the amount
of fine and high ash coal particles is also increasing rapidly
(Gui et al. 2017b). Cleaning of fine and high ash coal is
proven difficult, particularly for low rank coal. Therefore,
the development of low-cost and high-efficiency flotation
process has become an important development direction of
the coal beneficiation industry, which plays a crucial role in
improving the utilization rate of coal resources and protect-
ing the ecological environment.
Flotation utilizes the difference in surface hydropho-
bicity of valuable and gangue minerals to realize their sepa-
ration during which hydrophobic minerals are captured by
bubbles and float up to the froth layer whereas hydrophilic
