2026/08/04
The disc granulator (also known as a pelletizing disc or pan granulator) is a machine that uses a rotating disc to agglomerate and granulate powdery or granular materials. Its core component is a circular disc mounted at an incline, with an angle typically adjustable between 40° and 50°. As powdery material is fed onto the rotating disc via a conveyor belt, it is subjected to forces from three directions: centrifugal force from the disc's rotation flings the material toward the rim; gravity pulls it toward the bottom of the disc; and friction causes it to move along the disc's surface. The combination of these forces causes the material to follow a parabolic trajectory, colliding, bonding, and rolling to grow in size—much like a snowball—layering into spherical granules until they naturally spill over the disc's edge due to gravity.
The disc granulator achieves a granulation rate of over 93%. Featuring a disc bottom reinforced with multiple radial steel plates and a flexible belt drive system, the equipment is robust, durable, and energy-efficient. Both the disc inclination angle and rotation speed are adjustable, allowing operators to fine-tune parameters based on material characteristics and target granule size. The disc interior is lined with high-strength fiberglass-reinforced plastic (FRP) or stainless steel, ensuring corrosion and wear resistance. Its thickened, weighted, and sturdy base design ensures stable operation without the need for anchor bolts. The reducer and motor are connected via a flexible belt drive, ensuring smooth startup, effectively cushioning impact forces, and extending the equipment's service life.
One of the most underrated advantages of the disc granulator is its "ambient temperature" operation. Unlike rotary drum granulation, which requires steam heating or high-temperature drying, the entire pelletizing process in a disc granulator is a purely physical operation. It involves no heating elements or high-temperature flue gases. Consequently, functional microbial strains added during granulation—such as Bacillus subtilis, phosphate- and potassium-solubilizing bacteria, or other beneficial flora—are not deactivated by heat damage, ensuring the full preservation of microbial activity in the finished granules. For manufacturers of bio-organic fertilizers, this is not merely a matter of equipment selection, but a fundamental issue regarding the preservation of the product's core value.
The disc granulator also excels at processing materials with high moisture content. Take, for example, composted livestock manure such as chicken or cattle manure; these materials typically have moisture levels ranging from 25% to 40%. During the granulation process, raw material powder and atomized water are first uniformly mixed in a double axis mixer to form seed granules (nuclei), which are then fed into the granulation disc to complete the process. The moisture content of the granules is controlled at 12%–14%, allowing them to proceed directly to the subsequent screening stage.
