A large rotary kiln is a heavy-duty industrial equipment typically used for the thermal processing, drying, or calcination of materials. It features a long cylindrical structure with one or more internal support devices, driven to rotate by an electric motor. The interior of the rotary kiln is typically divided into multiple zones, including material loading, heating, calcining, and cooling zones, where materials undergo various treatment processes. This equipment finds wide applications in industries such as cement production, metallurgy, chemical engineering, and environmental protection.