Hydrodynamic Investigation of the Air Cleaning Process From Fine Coal Dust

<title>Abstract</title> In this study, a structurally improved dust-settling chamber was developed and experimentally tested to efficiently clean air from fine-dispersed coal dust. To enhance the coagulation of dust particles, 18 rows of self-cleaning hanging chains were installed in the upper inner part of the device. In addition, 12 water-spraying nozzles were arranged in a zigzag pattern to increase wet-cleaning efficiency. During the research, the effects of air velocity, water consumption, hydraulic resistance, and the number of chains and nozzles on the device’s performance were investigated. The results showed that when the air velocity increased from 0.5 m/s to 2.5 m/s, the cleaning efficiency rose from 35.4% to 99.1%. The optimal operating conditions of the device were determined as follows: air velocity — 2.5 m/s, hydraulic resistance — 700 Pa, hydraulic resistance coefficient — 7.2, and Reynolds number — 7432. Using the improved dust-settling chamber, the concentration of fine dust particles up to 5 µm in size was reduced from 31.1% to 13.8%. The results of the study have practical significance for improving air purification efficiency in industrial enterprises and reducing environmental load.