Raw Material Factors

Abnormal moisture content is a primary cause of excessive fine powder in pellets. When moisture is too low (<10%), raw materials become overly dry, lacking sufficient binding force during pelleting—this leads to fragmentation and powder generation. To resolve this, hydrate materials before crushing to maintain moisture at 12%~15% (for livestock/poultry feed) or 15%~18% (for aquatic feed); equipping a steam conditioner can also supplement moisture (3%~5% of material weight) and enhance plasticity. Conversely, excessive moisture (>18%) increases material viscosity, resulting in "mud-like" pellets that crack and shed powder after drying. Solutions include sun-drying or using a rotary dryer to reduce moisture, and adjusting conditioning temperature to 75~85°C to promote evaporation and starch gelatinization.

Unreasonable raw material ratios also contribute to the issue. High fiber content (>30% for straw or husk) leads to loose pellet structures due to insufficient binders (e.g., starch, protein), reducing internal cohesion. Address this by reducing high-fiber material proportion or adding binders (5%~10% flour, 3%~5% molasses, 2%~3% bentonite); preprocessing fiber materials (crushing to 1~2mm or steam extrusion to break fiber structure) is another effective measure. Additionally, excessive fine powder (>60% passing 80-mesh sieve) creates internal voids, causing over-compaction and rebound fragmentation. Adjust crusher screen size (e.g., from 2mm to 3mm) to maintain a 7:3 coarse-to-fine ratio, and add 1%~2% oil (lard or vegetable oil) to fill voids and strengthen pellet binding.