The forced discharge device is a key component in a beneficiation ball mill. Its core function is to achieve targeted discharge of slurry through a mechanical structure, thereby avoiding the over-grinding phenomenon caused by the high slurry level in traditional overflow ball mills. This device typically consists of three parts: a grate plate, a fan-shaped lifting device, and a hollow shaft. The grate plate, the core component, is covered with discharge holes with diameters of 7-20 mm. This hole prevents the escape of steel balls while allowing qualified slurry to pass through. As the ball mill drum rotates, radial ribs installed at the discharge end lift the slurry into the hollow shaft, completing the forced discharge process. This design significantly differs from the natural overflow method, resulting in a discharge level 30%-40% lower than that of an overflow ball mill, effectively shortening the residence time of ore particles within the mill.

The forced discharge device, through its unique operating principle, significantly improves beneficiation efficiency and product quality. As the drum rotates, centrifugal force forces the slurry through the small holes in the grate and is rapidly lifted by the radial ribs to the hollow discharge shaft. This process ensures forced slurry flow, allowing qualified particles to be discharged promptly and avoiding the particle retention problem common in traditional overflow ball mills.

Its core advantages are reflected in three aspects: First, the low slurry surface design reduces over-crushing, especially for brittle minerals (such as galena and sphalerite), providing a significant protective crushing effect, increasing the proportion of -200 mesh products by 15%-20%. Second, forced discharge maintains a stable slurry concentration within the mill, avoiding the loss of separation efficiency caused by slurry viscosity fluctuations and providing more uniform feed for subsequent flotation or magnetic separation steps. Finally, this device allows the mill to load more steel balls (filling rate can reach 40%-50%) without accidentally discharging small balls, thereby enhancing the impact and grinding action of the grinding media and increasing the processing capacity by 30%-40% compared to overflow ball mills of the same specification. These characteristics make it an ideal choice for processing high-hardness ores (such as magnetite and chalcopyrite) or for beneficiation scenarios requiring strict particle size distribution.