Enhancement of Regional Spatial Motion Behavior under the Synergistic of Strong Amplitude and Weak Airflow in Fine Coal

With the development of dry separation technology, the combination of vibration and airflow has provided a vital separation effect in dry separation. The regional spatial motion behaviors of fine coal have been investigated through the utilization of a vibratory gradient dry separator, which employs a combination of strong amplitude and weak airflow. The major directions of separation bed are X and Z axes, and the amplitude can reach 6.88 and 3.78 mm, respectively. The significant factors were investigated on the spatial distribution of fine coal density, including air velocity (VA), vibration frequency (f), and bed transverse inclination (AH). With the evaluation index of ash segregation (SA), the significance decreases in the following order: f > VA > AH. The product SA reached 1.838, and the yield and ash content of fine coal were 57.57 and 12.49%, respectively. Under the action of strong amplitude and weak airflow, light-density and heavy-density coal particles realize regional spatial density separation and stratification along the separation bed.