Gas nozzle

spraydryinghollow-cone

Installing the right atomizer is an essential step to ensuring spray drying success. The atomizer must fulfill several important functions: 1. It must disperse the feed material into small droplets, which should be well distributed within the dryer and mixed thoroughly with the hot gas. 2. The size of the droplets produced must be compatible with the required product particle size characteristics. 3. The droplets produced must not be so large that they are incompletely dried, nor so small that product recovery is difficult – small particles may also overheat and become scorched. 4. The atomizer must act as a metering device, controlling the flow rate at which the material is fed into the spray dryer. The properties of the feed stock are directly related to the finished particle size. Therefore density, viscosity, percentage solids, abrasive awareness, and any other characteristics ali need to be considered. The liquid properties should be established at the température |corresponding to the liquid in the nozzle. Feed stocks are often sprayed at elevated températures to decrease viscosity, thereby improving atomization. The effect of each liquid property on droplet size is usually established by actual test. However, Delavan's field experience shows that these effects can be closely estimated from the following correction factors.