The Sedimentation Mechanical Properties of Coal and Gangue Particles at Different Granularity Levels
2025
Chengyong Liu | Wenzhe Gu | Haijun Zhang | Xiangyun Shi | Quanzhi Tian | Hainan Wang | Yuejin Zhou | Zhicheng Liu | Bolong Zhang
Coal gangue, the primary bulk solid waste generated during coal utilization, requires decarbonization and the enrichment of valuable components such as calcium and magnesium through methods like hydrocyclone separation for comprehensive utilization. This study observed the free-settling behavior of coal gangue particles using a high-speed dynamic image analysis system and analyzed their kinematic characteristics to guide the hydrocyclone separation process. The results indicate that particle size and density significantly influence settling behavior. Fine-grained, low-density particles exhibited more pronounced directional deflection and velocity fluctuations, while high-density coarse particles demonstrated higher settling velocities. Based on terminal velocity, the drag coefficient of fluid resistance acting on particles was calculated. The findings show that high-density coarse particles have larger drag coefficients, likely due to fluid disturbances and the hydrophobic nature of particle surfaces. Additionally, the mechanical properties of settling motion were analyzed, indicating that gravity dominates the settling process of coarse particles, while fine particles are subjected to relatively balanced forces. Furthermore, density variations primarily affect hydrodynamic drag, which is related to the surface properties of particles. Therefore, enhancing the centrifugal force field through cyclone structural optimization is necessary to improve separation precision for fine coal and gangue particles.
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by Multidisciplinary Digital Publishing Institute