In the process of organic fertilizer production, powder materials are transported to disc granulator by belt conveyor. The inclination angle is 50 ° The turntable rotates with the material. Like rotary drum granulators, disc granulators use wet granulation to shape particles.
When the material reaches a certain height, its gravity and inertia separate from the disc, slide along the bending path, and complete the rolling required by granulation under the action of force.
At the same time, the liquid sprayed by the spraying system is evenly sprayed on the rolled material to condense into particles, so as to complete the whole granulation process.
Since the mid-1980s, extrusion method has been greatly developed, and more and more industrial production equipment has been established in various places. Now, extrusion granulation compound fertilizer production line technology has become an international fertilizer research center. A new production technology of compound fertilizer was recommended.
Working principle of extrusion granulation of compound fertilizer production line:
The material is fed into a pair of counter rotating roll gaps (bite zones) of the roll granulator. To form a compact sheet of material under extrusion. After crushing and sieving the flake, the granular product with the required size can be obtained.
The formation mechanism of extruded pellets in compound fertilizer production line is as follows
At present, the general explanation of the material forming mechanism in the extrusion process is that after the material is compressed, the particles will be rearranged, and the air between the particles will be removed, so as to remove the voids in the material.
After further compression of the material, due to their different characteristics, the material particles will be in the following two situations: when the material is fragile, some particles will break, thus filling the remaining gap. In addition, if the atoms or molecules in the environment can not be rapidly decomposed into new particles, the free chemical bonds on the broken new surfaces will form strong recombination bonds when the new surfaces contact each other.
In the extrusion process of pelletizer used for fertilizer, the particles of material can also form solid bridge. The energy supplied to the system in the form of pressure will generate heat energy at the contact point of the material particles, thus melting the material. When the temperature of the material decreases, a solid bridge is formed.
Main equipment of extrusion granulation compound fertilizer production line
1. Forced feeder
One of the advances in extrusion granulation compound fertilizer production line technology is the use of forced feeding in fertilizer granulator, which is usually achieved by the driving force of screw. The extrusion process adopts the form of gravity free feeding.
Forced feed, easy to control the feed speed and reduce the slip phenomenon in the bite area. More importantly, the material can be partially degassed and compacted in advance in the forced feeder, thus greatly improving the product quality.
2. Crushing equipment
The flakes obtained by extrusion must undergo a so-called granulation process, such as crushing and sieving, to obtain the desired size of particles. The progress of pelletizing equipment is mainly due to a lot of experience gained in the relationship between the form of crushing equipment and products.
Zhengzhou SX Granulator Manufacturing Factory vigorously promotes energy-saving, environmental protection, high-efficiency new extrusion granulation compound fertilizer production line technology, and continuous progress and improvement.