Blade parameters optimization of pendulum mill based on discrete element analysis of particle kinematics

In the grinding process of pendulum mills, blade parameter design significantly influences production efficiency. Blades throw the particles to the grinding area for grinding, also the blades design controls the particle movement trajectory. By using discrete element analysis software Rocky DEM, the grinding process is simulated in this paper. A response surface experiment of blade angle and length was conducted. Through analysis of particle number reaching grinding area, the influence laws of particle kinematics and grinding rate were revealed. With increasing blade angle or length, the throwing height and the number of particles in the grinding area increase. However, particles could not be effectively captured under extremely high blade angle and length, which reduced the grinding rate. The response surface results showed that the interaction of blade length and angle was significant, and the ranges of optimal blade angle and length are determined as 35°–38° and 225–245 mm, respectively. At the optimal blade parameters of 36°-227 mm, the grinding rate is 76.7%, 8% higher than that of the industrial blade parameter (32°-205 mm, 68.7%). This study provides a theoretical basis for the optimization design of the blade parameters of pendulum mills.