Effect of slurry conditioning on flocculant-aided filtration of coal tailings studied by low-field nuclear magnetic resonance and X-ray micro-tomography

Pengfei Hu; Long Liang; Guangyuan Xie; Shaoqi Zhou; Yaoli Peng

International Journal of Mining Science and Technology (Nov 2020)

Effect of slurry conditioning on flocculant-aided filtration of coal tailings studied by low-field nuclear magnetic resonance and X-ray micro-tomography

Pengfei Hu,
Long Liang,
Guangyuan Xie,
Shaoqi Zhou,
Yaoli Peng

Affiliations

Pengfei Hu: Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, China University of Mining and Technology, Xuzhou 221116, China; School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, China
Long Liang: Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, China University of Mining and Technology, Xuzhou 221116, China; School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, China; Corresponding author.
Guangyuan Xie: Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, China University of Mining and Technology, Xuzhou 221116, China; School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, China
Shaoqi Zhou: Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, China University of Mining and Technology, Xuzhou 221116, China; School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, China
Yaoli Peng: Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, China University of Mining and Technology, Xuzhou 221116, China; School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, China

Journal volume & issue: Vol. 30, no. 6
pp. 859 – 864

Abstract

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The present work aimed to study the effect of slurry conditioning on flocculant-aided filtration of coal tailings by the analysis of filtration kinetics and filter cake structure. Laboratory filtration tests of the coal tailings showed that both the shear rate and agitation time have significant effects on filtration rate and cake moisture. Moderate agitation at the shear rate of 92 s−1 was favorable for fast filtration, but high cake moisture was encountered. The low-field 1H nuclear magnetic resonance (NMR) measurements of the filter cake showed that the slurry conditioning has a significant effect on the residual water in large pores and a negligible effect on the residual water in small pores. The X-ray micro-tomography (XRM) measurements indicated that the filter cake formed at the shear rate of 92 s−1 has more macro-pores and higher porosity than that formed at the shear rate of 53 s−1, hence more residual water was entrapped in filter cake. The slurry conditioning in the presence of flocculant will change the structure of filter cake and affect the filtration performance. There was a paradox between fast filtration rate and low filter cake moisture. The findings enable better understanding of the effect of slurry conditioning on flocculant-aided filtration of coal tailings.

Published in International Journal of Mining Science and Technology

ISSN: 2095-2686 (Print); 2589-062X (Online)
Publisher: Elsevier
Country of publisher: Netherlands
LCC subjects: Technology: Mining engineering. Metallurgy
Website: https://www.journals.elsevier.com/international-journal-of-mining-science-and-technology

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