ID 321

Measurements of the throw width and impact pressure of industrial tank cleaning nozzles

 

Abstract:

Tank cleaning and clean in place (CIP) applications are common processes in industry, however the selection of a tank cleaner remains highly dependent on the process material, geometric limitations, and various other factors, like temperature, chemical cleaning agents and total time to clean. Without a basis for selection, the effectiveness of cleaner remains subjective. In this study, we consider the local mechanical impact pressure as quantitative, unbiased parameter to determine the cleaning effectiveness. Only limited data about the impact pressure in far distance for industrial nozzles has been published. Therefore, we have measured impact pressure and jet throw width of various tank cleaning nozzles. Both measured values are fit to a simple semi empirical model depending on the orifice size, spray pattern, gauge pressure and spray distance. This model can be finally used to compute the impact pressure on real process geometries. Experiments were performed in two parts, impact and jet throw width. For impact tests, the average static impact pressures and the deviation over time of a surface of round liquid jets for an orifice diameter range from 1.9 to 15.8 mm and various flat sprays for gauge pressures from 0.05 to 1.5 MPa and hence for a wide range of water flow rates from 1 to 500 l/min were measured. Tests were performed with horizonal spray distances ranging from 0.25 to 6 m; surpassing previous studies which were generally performed at spray distances below 1.5 m. Throw width experiments were performed using round liquid jets. As the jets disintegrate into droplets over time and path length due to jet break up, the throw curve maximum width is limited due to gravity and aerodynamic drag up.