What is the working principle of the Rotary Kiln?

A rotary kiln typically consists of a feeding device, a furnace, an electrical control cabinet, and a kiln tube. Inside the furnace, there are supporting devices that can hold up the kiln tube. An electric motor drives a large gear to rotate the kiln tube. Materials enter from the feed end via the feeding device and pass through different zones such as the heating zone, calcining zone, and cooling zone to undergo the required processing.