Before feeding materials into an organic fertilizer double axis mixer, raw materials—such as livestock and poultry manure, crop straw, sludge, and oilseed cakes—must undergo standardized pre-treatment. This ensures uniform mixing, prevents machine jamming, and facilitates effective fermentation. First, the moisture content of the raw materials must be controlled. High-moisture materials—such as manure and sludge—require adjustment through air-drying or by adding dry straw, sawdust, or mature compost to bring the moisture level within the range of 50% to 65%. If the material is excessively wet and sticky, it tends to clump together and adhere to the mixing shaft; conversely, if it is too dry, it generates excessive dust and results in poor mixing efficiency.

Second, size reduction is required. Coarse-fiber materials—such as straw, rice husks, and tree branches—must be shredded to lengths of 2 to 5 cm. Clumped manure, soil lumps, and oilseed cakes must be crushed to a uniform particle size to prevent large blocks from causing mixing obstructions, blade wear, or uneven discharge. Simultaneously, impurities must be removed; hard objects—such as stones, plastics, metal wires, and fabric scraps—must be cleared from the raw materials to prevent damage to the mixing blades, the main shaft, and the gearbox.

For formula-based production, ingredients must be weighed and prepared in advance according to the specific recipe. Nitrogen sources, carbon sources, microbial inoculants, and passivating agents should be measured out proportionally to avoid compositional fluctuations caused by direct, unmeasured dumping. Auxiliary ingredients that are prone to moisture absorption and clumping should be broken up and screened beforehand to ensure the material remains loose and free-flowing. Furthermore, certain raw materials may require pre-fermentation or pre-piling (composting) to reduce viscosity, eliminate insect eggs and pathogens, and minimize mixing resistance.

During winter or in high-humidity environments, mature organic fertilizer may be added as a conditioning agent to improve material flowability. Once the pre-treatment process is complete, the materials can be fed uniformly into the dual-shaft mixer. This approach significantly enhances mixing quality, minimizes material blockages, prevents motor stalling, reduces equipment wear, and ensures the stable operation of subsequent fermentation and granulation processes.