Abstract: As an important devices in new oxygen converter gas recovery (OG) system of converter's primary dedusting, atomization characteristics in high efficient spraying tower has an immediate impact on the operational efficiency of system. The atomization effect of pressure spiral nozzle was studied experimentally under different flow rates based on the flash photography method by means of image processing technology, and the droplet atomization uniformity was evaluated qualitatively and quantitatively by particle size distribution and span value.The results show that with the drop of droplet, the number of droplet of small particle size increases, and the distribution uniformity of droplet size decreases. The Sauter mean diameter (SMD) of atomization field increases with the fluid flow of pressure spiral nozzle with different apertures. For the pressure spiral nozzle that is presented in this study, the nozzle with aperture 1.5 mm and fluid flow 0.15 kg/s is the best for atomization effect, and SMD value is the minimum.