Numerical investigation into the influence of mould shape on the pulverulention of pellet

Pellet has advantages of convenient transportation and improving powder performance, so it has been widely used in biomass-energy, feed industry, fertilizer and waste disposal industry. Low pulverulent ratio is the main target of high quality pellets, therefore FEM method was used to predict the influence of mould shape on the pulverulention of pellet. The fundamental principle of Drucker-Prager Cap model which material properties are relative density dependent was discussed in this article. Numerical investigation into the influence of moulds shape on the pulverulention of pellet was conducted in this article. The simulation results show that the pellets compressed by the moulds with concave arc type or small angle oblique line type hole have better outer wall surfaces than convex arc type and large angle oblique line type hole. The powder density of the pellets surface can be increased dramatically through changing the taper hole structure to multistage taper hole. The structure optimization of moulds can significantly improve the pulverulent ratio of pellets.