Jiutian large-scale calcining blast furnace slag rotary kiln project was completed in Thailand. Blast furnace slag enters the rotary kiln from the kiln tail. During the slow rotation of the kiln body, the slag moves along the kiln body toward the kiln head. At the same time, the fuel burns at the kiln head or in the kiln to produce high-temperature flames and flue gas. The hot flue gas contacts the slag in countercurrent to heat and calcine the slag. Under high temperature, the mineral composition inside the slag changes and its activity is improved. The blast furnace slag rotary kiln manufactured by our company has mature technology and good calcination uniformity.