Abstract: In order to study the effect of material properties and silo structure on material flow capacity， and solutions for high-viscosity materials blocking inside the silo，the influence of the water content and particle size of the material in the fine ore silo of the Heshangqiao Concentrator on the friction angle of the material and the influence of the semi-top angle of the silo and the size of the discharge port on the flow performance of the material were analyzed based on Jenike shear theory.The results showed that the internal friction angle of the materials in the powder ore silo increases with the increase of the water content， when the water content between 10% and 11%， the internal friction angle reaches the maximum value of 47.2°， and then gradually decreases with the increase of the water content. The internal friction angle of the material gradually decreases with the increase of the particle size. When the particle size exceed 3 mm， the change of the internal friction angle tends to be gentle， stable at about 42°. The unreasonable design of the semi-top angle and the size of the discharge port can easily cause the blockage of the warehouse.Based on the above research results， a pneumatic cleaning and flow aid scheme is proposed aiming at the blockage of the powder ore silo. The results showed the effective volume ratio and effective reserves of the powder ore silo are increased by more than 40%，which increases the benefits of more than 14 million yuan for the concentrator under the premise of an annual processing capacity of 5 million tons.

Key words: high viscosity materials, powder ore silo, internal friction angle, pneumatically removal of blockages