Disc Pelletizers (also known as pan pelletizers) are the equipment of choice for converting powdered materials into uniform, round pellets. Pelletizing, like all types of agglomeration, offers a variety of benefit, such as reducing volume, stabilize mixtures, reduce dust problems, control hardness, reduce packing, improve Product Performance etc. The main factors affecting the pelletizing efficiency of disc granulator are as followings:

First. Fitness of mixture

The rough mixture will be difficult for pelletizing. The small specific surface area and poor plasticity of the mixture are the main reasons that affecting the output of the pellet. If too fine mixture, it will form the big ball because the adsorption capacity of the particles is greatly increased with the big specific surface area.

Two. Slope and line speed of granulator

The slope of granulator influences the filling factor and the residence time of the material in the disc. With small slope and large material filling factor, the residence time will be long. With the big slope and small filling factors, the residence time will be short. If the slope less than 45°, it will be difficult to pelletize or liable to pelletize the big ball, also its production will be decreased. If more than 55°, the ball diameter will become smaller and bring out the powder easily. Therefore, too larger or too smaller dip slope will be adverse to the production.

In addition, the line speed of granulator should be appropriate. If the line speed is too low, the mixture in the disc will be sliding but not rolling and it will be not easy to pelletize. If too high, the ball will be attached to the plate and rotate with the plate because the centrifugal is large, therefore this situation also will affect to pelletize.  

Three.Margin plate height of granulator

The disc of granulator is made up of a margin plate and a disc bottom. The margin plate is welded on the perimeter of the disc bottom, which will control the diameter of the pellet and the residence time of feed in the plate. Therefore it will affect the output and quality of granulator. If the margin plate is too high, the raw nodules already fit to the requirements cannot be unloaded in time and then still rotate in the disc which will make the diameter larger and affect the output of the granulator. If the margin plate is too lower, the raw nodules will be out of the disc quickly when it has not yet formed a certain grain size and certain strength, even will bring out part of powder along with. Then it will affect the quality of the raw nodules.

Four. Quantity and location of the scraper 

The role of the scraper: (1) make the pan bottom layer keep a certain thickness bed of material, to ensure the ball disc in the normal production and avoid the abrasion of the pan bottom; (2) to control the movement of material in the plate. The appropriate quantity and location of the scraper not only can improve the output, but also can improve the quality of the material.

Five. Water-added, feeding location and quantity of granulator

Water-added, feeding location and quantities of granulator have great influence on the output and quality. If water-added and feeding location in the area of pellet,it will make the ball diameter increase and the output decrease. If the water-added location concentrated in the feeding area, it will make the cue ball increase and the diameter of the ball small.