doi:10.16186/j.cnki.1673-9787.2022080041

Received:2022/08/21

Revised:2023/02/27

Published:2024/01/25

Experimental study on flocculation and settlement of slime water with high ash fine mud in the mining area of Henan Province

LU Zhongliang1,2,3, WANG Bohao1, YU Yuexian4, SHI Changliang5, HE Jun1,2,3, WANG Jie6

1.College of Safety Science and Engineering，Henan Polytechnic University，Jiaozuo  454000，Henan，China；2.Key Laboratory of Gas Geology and Gas Control，Henan Polytechnic University，Jiaozuo  454000，Henan，China；3.The Collaborative Innovation Center of Coal Safety Production of Henan Province，Henan Polytechnic University，Jiaozuo  454000，Henan，China；4.College of Chemistry and Chemical Engineering，Xi’an University of Science and Technology，Xi’an  710054，Shaanxi，China；5.School of Chemistry and Chemical Engineering，Henan Polytechnic University，Jiaozuo  454000，Henan，China；6.College of Civil Engineering，Taiyuan University of Technology，Taiyuan  030600，Shanxi，China

Abstract: Objective With the improvement of coal mining mechanization and the popularity of the heavy media beneficiation process，the content of high ash and fine mud in the flotation coal slurry gradually increases.High-ash fine mud is the most direct factor affecting the settling efficiency of coal slurry water，and the treatment of high-ash fine mud in coal slurry water is directly related to the production of coal resources and the use of water resources. Methods Aiming at the characteristics of coal slurry water with high ash and fine mud in Henan mining area，orthogonal tests were designed to test the effects of different kinds of flocculants and mixing speeds on the settling rate of coal slurry water and the interaction between them，so as to improve the efficiency of coal slurry water settling. Results The results show that the dispersion and flocculation performance of sodium hexametaphosphate and polyacrylamide are better，and the influence of stirring speed，sodium hexametaphosphate dosage，and polyacrylamide dosage on the settling rate of high fine mud content slime water decreases in order，and the reciprocal relationship between stirring speed and polyacrylamide dosage has the most significant influence on the settling rate.When sodium hexametaphosphate dosage is 40.08 mg/L，polyacrylamide dosage is 5.75 mg/L，and stirring speed is 411.12 r/min，the settling rate can reach 95.5%.The reason for the increase of sedimentation rate is that the high ash fine mud flocculation process flocs into balls obviously，the flocculant bridging effect can make the dispersed particles agglomerate and develop into spherical，the long irregular particles obviously reduced，the change of the particle group particle shape contributes to the sedimentation of the coal slurry water，the mixing speed under a certain particle shape to maintain a more regular，can increase the probability of sedimentation，so that the coal slurry water to be effective sedimentation. Conclusion By improving the particle size and shape characteristics of the particles in the coal slurry water，the settling efficiency of the high ash and fine mud coal slurry water in Henan mining area can be effectively improved.The results of the study can provide theoretical support and practical reference for the treatment of high ash fine mud coal slurry water.

Key words:mining area of Henan Province;slime water;high fine mud content;settlement efficiency;granular form