How to Avoid Rough Surfaces & Burrs in Pellet Mill Production
Rough surfaces and burrs on biomass pellets produced by a pellet mill hurt product appearance, storage-transport performance and combustion efficiency. This issue is mainly caused by worn or rusted mold hole inner walls, unpolished new molds, uneven raw material mixing, unstable moisture content, or mixed-in fine impurities.
To fix this problem, regularly inspect the molds used in your pellet mill: polish the mold hole inner walls if wear is slight, or replace them directly if wear is severe. New molds must be treated with fine sandpaper or special grinding rods on the inner wall before use to ensure smoothness without burrs. Meanwhile, standardize raw material pretreatment: extend mixing time for uniform materials, stabilize moisture content at 12%-15%, and add sieving and magnetic separation after crushing to remove sand, gravel and metal debris. In daily pellet mill operation, establish a regular mold inspection system, control crushed raw material particle size at 3-5mm, and feed materials at a constant speed.