A double roller press granulator is a highly efficient and energy-saving dry granulation equipment, widely used in chemical, fertilizer, and building materials industries, playing a crucial role, especially in fertilizer production lines. Its core principle is to use high-pressure mechanical extrusion to shape powdery materials through intermolecular forces, eliminating the need for additional binders and achieving green and efficient granulation throughout the process.
The core power source for the equipment is the transmission system. An electric motor drives a pulley, which, after being reduced in speed and torque by a reducer, drives a pair of parallel high-pressure rollers to rotate at a relatively uniform speed. The transmission methods vary slightly between different models; some use split gears to achieve double-roller linkage, while others are directly driven by a reducer with dual output shafts, ensuring synchronous rotation and balanced pressure between the two rollers, laying the foundation for stable granulation.
The granulation process mainly consists of three key stages. First is the pre-treatment of the feed. After mixing and crushing, the powdery material enters the equipment through the feed hopper and is uniformly pushed between the two rollers by a screw feeder. The feed rate can be precisely controlled by an adjustment device to avoid material accumulation or insufficient supply affecting the molding effect.
Secondly, high-pressure extrusion molding is the core step in granulation. When the two rollers rotate relative to each other, a high pressure of 10-30 MPa is applied to the material, expelling air between the particles and shortening the particle distance, achieving tight adhesion through adsorption. The pre-set grooves on the roller surface can be replaced as needed, extruding the material into particle shapes consistent with the grooves.
Finally, there is crushing, screening, and recycling. The shaped particles are peeled off the roller surface by a scraper and enter the crushing and molding chamber, where they undergo secondary processing by a crushing roller driven by the drive roller. They are then screened, with qualified particles discharged through the discharge chute, while unqualified powder is returned to the feeding system for re-granulation, ensuring full utilization of the raw materials.
The double roller press granulator eliminates the need for a drying process, significantly reducing energy consumption. It is also simple to operate and highly continuous. Its core working principle is to use mechanical extrusion to shape the material, ensuring particle strength while simplifying the process, making it a preferred equipment for modern industrial particle processing.
