A ball mill is a type of grinding equipment. The grinding process in a ball mill is enclosed. Under these enclosed external conditions, ventilation inside the grinding chamber is very important, as it directly affects the output and quality of the equipment.

The benefits of proper ventilation within the ball mill:

(1) Timely removal of qualified fine powder, reducing over-grinding and the buffering effect of fine powder, thereby improving grinding efficiency;

(2) Timely removal of heat and water vapor generated during grinding, reducing the temperature and humidity inside the mill, preventing sticking, ball sticking, or clogging of the diaphragm plates and grate holes, thus increasing ball mill output;

(3) Preventing gypsum dehydration and preventing false setting of cement;

(4) Reducing dust emission from the mill head and improving environmental hygiene.

Some people believe that ball mill ventilation is only related to fan performance, which is incomplete. In fact, mill ventilation is directly and closely related to the entire ventilation and airlock system. For example, many ball mills still designed in 1965 have a 90-degree right-angle feed inlet, creating a material stagnation zone at the corner. This significantly reduces the actual air intake cross-sectional area, severely hindering mill ventilation—what we often call the “ventilation bottleneck phenomenon.” Theoretically, the inlet cross-section should be the same as the actual cross-section of the mill cylinder. While this is practically impossible, under feasible conditions, the larger the inlet cross-section, the better, minimizing the ventilation bottleneck phenomenon. This necessitates modifications to the feed inlet in actual production.

Similarly, the airlock system must be properly implemented. Otherwise, the fan’s air will be directly drawn away from the discharge port, creating a ventilation short circuit, resulting in very little airflow inside the mill. Many factories currently add flap valves to the discharge port, but their effectiveness is not ideal, requiring the redesign of the airlock device.