Spray granulation dryer is mainly composed of feeding system, drying system, dust removal system, heating system and electrical system, and each system includes some related equipment.
The feeding system is composed of mixing barrel, filter, diaphragm pump and spray gun. The ball-milled secondary slurry is transferred from the ball mill to the mixing tank, pumped and conveyed by the diaphragm pump through the filter, and then enters the drying tower through the spray gun.
The slurry enters the drying tower from the spray gun nozzle to start the spray granulation drying process. The specific process is divided into three stages:
1. Slurry atomization
The slurry is pressed into the drying tower from the nozzle by the diaphragm pump in the feeding system at a certain pressure, the energy of the pressure is converted into kinetic energy, and the slurry is sprayed from the nozzle from bottom to top to form a high-speed liquid film, which then splits into droplet. The droplet size produced by atomization is inversely proportional to the pressure, and the production capacity of the nozzle is directly proportional to the square of the pressure.
2. Mist particles are dried into balls
The mist particles and hot air work in a mixed flow mode. The hot air enters the tower through the hot air distributor on the top cover. The hot air distributor generates a streamlined air flow downward. air flow. The droplets form a spherical shape due to the surface tension, and because the droplets have a large surface area, the water evaporates and dries quickly, and finally shrinks to form a dry spherical particle powder.
The formed spherical granular powder gradually settles in the drying tower and is separated from the hot air. The funnel cavity at the bottom of the tower makes the granular materials gather and discharge from the discharge port. The finer particles and the dry air are sucked by the exhaust fan connected to the upper part of the funnel and enter the dust removal system.
3. Unloading of granular powder
The supply fan, the drying tower, and the exhaust fan that deliver hot air to the drying tower make up the drying system.
The dust removal system is composed of a high-efficiency cyclone separator, a bag filter, and a centrifugal fan. The exhaust fan sends the finer particles into the high-efficiency cyclone separator together with the dry air. After effective separation, the finer particles enter the collection cylinder at the bottom of the separator for recovery, and the remaining exhaust gas containing a small amount of fine particles is sucked into the bag filter by the centrifugal fan and collected again for dust removal, realizing the harmless treatment of the exhaust gas. Exhaust gases are discharged from the chimney.