講演情報
[PE1-001]Effects of Flatness Ratio on the Jig Separation of Crushed Plastic Particles
○Theerayut Phengsaart1, Arisa Azuma1, Carlito Baltazar Tabelin1, Naoki Hiroyoshi1, Mayumi Ito1 (1. Hokkaido University)
In resources recycling, separation of crushed plastics is an important issue. In this study, effects of shape of crushed plastic (flatness ratio: thickness/breadth of particles) on jig separation were investigated using crushed ABS plates (specific gravity, 1.03; thickness, 2 and 3 mm), and PS plates (specific gravity, 1.06; thickness, 2 and 3 mm).
When crushed ABS plate with 2 mm thickness was used, particles with high flatness ratio (sphere-like particle) were recovered in the bottom layer and low flatness ratio particle (disk-like particle) were recovered in the top layer. This may be due to larger hydraulic drag force and slower settling velocity with disk-like particle.
When mixture of disk-like ABS and PS or mixture of sphere-like ABS and PS was used, heavier PS was recovered in bottom layer and lighter ABS was recovered in top layer. When mixture of disk-like ABS and sphere-like PS or mixture of sphere-like ABS and disk-like PS was used, heavier PS was recovered in bottom layer and lighter ABS was recovered in top layer, indicating that specific gravity is more dominant factor to decide the stratification than shape. In comparison with the mixture of sphere-like ABS and disk-like PS, separation efficiency (sharpness index) was higher with mixture of disk-like ABS and sphere-like PS, may be due to the slowest settling velocity for disk-like, lighter ABS.
When crushed ABS plate with 2 mm thickness was used, particles with high flatness ratio (sphere-like particle) were recovered in the bottom layer and low flatness ratio particle (disk-like particle) were recovered in the top layer. This may be due to larger hydraulic drag force and slower settling velocity with disk-like particle.
When mixture of disk-like ABS and PS or mixture of sphere-like ABS and PS was used, heavier PS was recovered in bottom layer and lighter ABS was recovered in top layer. When mixture of disk-like ABS and sphere-like PS or mixture of sphere-like ABS and disk-like PS was used, heavier PS was recovered in bottom layer and lighter ABS was recovered in top layer, indicating that specific gravity is more dominant factor to decide the stratification than shape. In comparison with the mixture of sphere-like ABS and disk-like PS, separation efficiency (sharpness index) was higher with mixture of disk-like ABS and sphere-like PS, may be due to the slowest settling velocity for disk-like, lighter ABS.