The suppression of airborne dust is a significant issue within the resources industry that has been highlighted by the re-emergence of lung diseases such as coal workers’ pneumoconiosis and silicosis. A prominent method for the control of airborne dust is the use of water spraying systems to suppress dust and minimise its liberation into the workplace. The challenge with water spraying systems for airborne dust suppression lies largely in the correct selection of nozzles to suit the application. This paper outlines work conducted by the University of Wollongong with funding from the Coal Services Health & Safety Trust to investigate the factors affecting the performance of water spraying dust suppression systems. Through this project, an innovative experimental apparatus was setup for the testing of nozzles under various dust and airflow conditions. This allowed for a parametric study to be conducted on the influence of factors such as water flow rate and pressure, droplet size, dust concentration, and dust velocity to be investigated. The outcome of this study was the introduction of an equation to compute a spray parameter based on droplet size, water flow rate, and spray velocity that can be used for the selection of nozzle for airborne dust suppression. Comparison between the computed spray parameter with the large number of tests conducted allowed for recommendations to be made that will aid in the selection of nozzles for airborne dust suppression systems using water sprays in the future.
Jon Roberts, Rongfu Liao, Ming Qiao, David Hastie and Peter Wypych, Research into the selection and efficiency of nozzles for airborne dust suppression, Proceedings of the 2023 Resource Operators Conference, University of Wollongong - Mining Engineering, February 2023, 152-160.