Research on the influence of nozzle structure parameters and surfactant-magnetised water on atomisation...

To effectively promote the efficiency of spray-based dust suppression, the influence of nozzle structure parameters and surfactant-magnetised water on atomisation characteristics was studied in this study. The experimental results show that the surfactant-magnetised solution boasts great wetting performance for coking coal at the surfactant concentration of 0.03 wt%. The droplet velocity was effectively improved, reaching 7.5 m/s at a distance of 50 cm. When the nozzle diameter was less than 1.5 mm, the growth rate of droplet particle size was small, but when the nozzle diameter was greater than 1.5 mm, the growth rate of droplet particle size was rapidly increased. There is no linear relationship between the height of the nozzle and the droplet size. Based on these studies, a dust removal system of this combined technology consisting of a surfactant-adding device, a magnetised apparatus and atomisation devices was designed and installed at a fully mechanised mining face. The respirable dust and total dust suppression efficiencies achieved were 85.3% and 90.4%, respectively.