Dosing interval of coagulant and flocculant influences settling behavior of coal slime

ABSTRACT

Using the high-speed motion acquisition system, we studied the settling process of the coal flocs under different addition interval time. The gray value and zeta potential of supernatant generally increased as the interval time increased, proving the effect of interval time on coal slime sedimentation. Furthermore, the interval time 25 s presented the smallest floc amount. The floc size and zeta potential were measured via the inverted fluorescence microscope and the micro electrophoresis, respectively. The interval time 25 s presented the fastest settling velocity. The floc amount in supernatant roughly decreased as the zeta potential increased. The settling velocity decreased with the settling time. The results can provide valuable insight into the development of technology for coal slime sedimentation.

KEYWORDS:

• Coal slimes
• floc
• coagulant
• flocculant
• interval time
• sedimentation

Acknowledgements

The authors gratefully acknowledge the Scientific Research Foundation for High-level Talents of Anhui University of Science and Technology (Grant No. 2021yjrc57), Anhui Provincial Key Research and Development Project (Grant No. 2022n07020001), Anhui Provincial Excellent Young Scientific Research Project (Grant No. 2022AH030085), Anhui Provincial Scientific Research Foundation for the Returned Overseas Chinese Scholars (Grant No. 2022LCX029), Anhui Province University Natural Science Research Major Project (Grant No. KJ2021ZD0046), and National Natural Science Foundation of China (Grant No. 52104242) for supporting this work.

Disclosure Statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Anhui Provincial Key Research and Development Plan [2022n07020001]; National Natural Science Foundation of China [5210424]; Scientific Research Foundation for High-level Talents of Anhui University of Science and Technology [2021yjrc57]; Anhui Provincial Scientific Research Foundation for the Returned Overseas Chinese Scholars [2022LCX029]; Anhui Province University Natural Science Research Major Project [KJ2021ZD0046]; Anhui Provincial Excellent Young Scientific Research Project [2022AH03008].