XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 587
coal qualities, the bed density is regulated by controlling
the content of coal powder and the bubbling phase, as illus-
trated in Figure 4.
Effect of Mesoscale Structure on Particle Segregation
On the basis of examining the influence of bubbles on the
movement of medium particles, scholars have also used
numerical simulation to study the influence of mesoscale
structure on the separation process of selected coal parti-
cles. Zhang et al. [9, 10] conducted a study using the Euler-
Lagrange method to investigate how the movement of
bubbles affects the mixing and separation of heavy particles
in fluidized processes. The study was illustrated in Figure 5.
The results revealed two aspects of the impact of bubbles on
particle stratification mixing. Firstly, when particle strati-
fication occurs with small particles in the upper bed and
large particles in the lower bed, bubbles tend to form in
the lower region. These bubbles carry large particles to the
bed surface, causing further stratification. Secondly, at high
gas velocities, the bubbles in the bed become larger and
move faster, resulting in the upward entrainment of both
large and small particles by the bubbles, leading to particle
mixing. The study also observed that the interaction forces
between gas and solids, as well as the drag force, are more
significant at the top and bottom regions of the bubbles.
Conversely, the interaction forces between solids and gas
decrease significantly at the sides and inside of the bubble
movement. Additionally, the collision force experienced by
particles in the emulsion phase is notably greater than that
in the bubble phase. These findings provide a theoretical
foundation for understanding the relationship between the
movement of mesoscale structures and the movement of
microscale particles.
The EMMS-DPM method was used by the research
team to simulate the convective environment, while the
DEM method was used to simulate the separation process
of specific coal. The findings of the study indicate that the
strong ability of bubble wake vortices to entrain particles
can result in the entrainment of both clean coal and gangue
particles to the bed surface or upper layer. The movement
of bubbles throughout the bed causes some clean coal par-
ticles to sink to the bottom. Figure 6 depicts the circular
movement formed by the interaction between bubbles
and surrounding medium particles, and the movement of
Figure 4. The principle of bed density adjustment in gas–solid fluidized bed[8]
coal qualities, the bed density is regulated by controlling
the content of coal powder and the bubbling phase, as illus-
trated in Figure 4.
Effect of Mesoscale Structure on Particle Segregation
On the basis of examining the influence of bubbles on the
movement of medium particles, scholars have also used
numerical simulation to study the influence of mesoscale
structure on the separation process of selected coal parti-
cles. Zhang et al. [9, 10] conducted a study using the Euler-
Lagrange method to investigate how the movement of
bubbles affects the mixing and separation of heavy particles
in fluidized processes. The study was illustrated in Figure 5.
The results revealed two aspects of the impact of bubbles on
particle stratification mixing. Firstly, when particle strati-
fication occurs with small particles in the upper bed and
large particles in the lower bed, bubbles tend to form in
the lower region. These bubbles carry large particles to the
bed surface, causing further stratification. Secondly, at high
gas velocities, the bubbles in the bed become larger and
move faster, resulting in the upward entrainment of both
large and small particles by the bubbles, leading to particle
mixing. The study also observed that the interaction forces
between gas and solids, as well as the drag force, are more
significant at the top and bottom regions of the bubbles.
Conversely, the interaction forces between solids and gas
decrease significantly at the sides and inside of the bubble
movement. Additionally, the collision force experienced by
particles in the emulsion phase is notably greater than that
in the bubble phase. These findings provide a theoretical
foundation for understanding the relationship between the
movement of mesoscale structures and the movement of
microscale particles.
The EMMS-DPM method was used by the research
team to simulate the convective environment, while the
DEM method was used to simulate the separation process
of specific coal. The findings of the study indicate that the
strong ability of bubble wake vortices to entrain particles
can result in the entrainment of both clean coal and gangue
particles to the bed surface or upper layer. The movement
of bubbles throughout the bed causes some clean coal par-
ticles to sink to the bottom. Figure 6 depicts the circular
movement formed by the interaction between bubbles
and surrounding medium particles, and the movement of
Figure 4. The principle of bed density adjustment in gas–solid fluidized bed[8]