2026/09/09
The first stage is "crushing," where the challenge lies in handling the decomposed material fresh out of the fermentation tank. With a moisture content typically ranging from 25% to 50%, these materials are highly viscous and fibrous; standard crushers clog almost immediately upon contact—blades get gummed up by wet material and screens become hopelessly entangled with fibers, causing the machine to idle without discharging product. The half-wet material crusher is specifically designed to handle this "semi-wet" state. It employs a tandem dual-rotor structure: material first enters the upper rotor's crushing zone, where it is broken down by high-speed rotating hammers; it is then propelled into the lower rotor for further fine crushing. Simultaneously, particles collide and grind against one another within the chamber, creating a dual-action crushing effect where both hammers and the material itself pulverize the feedstock.
The second stage is "turning," taking place in open-air fermentation tanks. If the piled organic material is not turned regularly, the interior becomes oxygen-deprived; aerobic microorganisms die off while anaerobic bacteria proliferate, generating pungent ammonia and hydrogen sulfide. Furthermore, the core temperature fails to rise sufficiently, leaving insect eggs and pathogens alive. The core of the double-screw compost turner consists of two parallel screw shafts rotating in opposite directions. During operation, the shafts counter-rotate at differential speeds, generating a complex motion that combines shearing, scattering, and inward gathering of the material. The equipment travels along rails spanning the fermentation tank; its spiral blades continuously scoop up material from the tank floor and convey it toward the center, where centrifugal force hurls it high into the air. This process turns oxygen-deprived material from the bottom to the surface for aeration, while surface-dried material is folded back into the interior to regain moisture.
The third stage is "granulation," which processes the organic material—now in powder form following crushing and fermentation. Although the nutrient content of this powder meets standards, its loose, airborne nature makes storage and transport inconvenient, necessitating a shift to a solid physical form. The double-roller press granulator employs a dry extrusion method: two high-strength rollers rotating in opposite directions instantly compress the powder into thin sheets under pressures ranging from 120 to 300 MPa; these sheets are subsequently crushed and screened to yield the final granules. The advantage of this dry process is that it eliminates the need for the dryers and hot-blast stoves required in wet granulation, thereby reducing the entire production line's overall energy consumption by 30% to 50%.
