In this work, the behavior of coal char particles adhering
to the
slag wall was studied. The effects of slag thickness and particle
size on the restitution coefficient and probability of deposition
were mainly discussed. In addition, the types of particle deposition
were also classified. The results of exploring the effect of particle
size on the coefficient of restitution show that the restitution coefficient
of coal char particles hitting the slag wall surface has a complex
dimensional effect, with a maximum and minimum coefficient of restitution
occurring at the same particle size, a phenomenon referred to in this
paper as the discrete effect. The minimum restitution coefficient
greater than 0 is regarded as the critical restitution coefficient
(ε
f), and it is considered that
particles with theoretical restitution coefficient higher than εf will bounce off the slag wall. With the particle diameter
of 600 μm as the boundary, ε
f first decreases and then increases. The maximum restitution coefficient
increases with an increasing particle size of less than 600 μm
and stays at a maximum value of 0.62 when the particle size is more
than 600 μm. Moreover, the fragmentation of particles occurs
at the particle size of 840–1600 μm. The discrete effect
was also observed in the experimental data for the investigation of
slag thickness, ε
f increases with
the increase of the slag thickness, and the maximum possible restitution
coefficient does not change with the thickness of the slag. In addition,
according to the statistics of the deposition probability, it is found
that the smaller the particle size, the greater the deposition probability,
the thicker the slag thickness, and the easier it is to deposit.