There are two kinds of rotary kilns used in alumina production. In the kiln, there is a kind of complex temperature control. It is a kind of wet kiln. There is also a kind of kiln which only dehydrates the attached water and crystal water of aluminum hydroxide at 1100 ℃ to turn it into powdered alumina. This kind of kiln belongs to drying property and becomes baking kiln. The two rotary kilns have the same structure and working principle, so they can be studied and analyzed in a unified way.

Picture of alumina rotary kiln production line

Process flow of alumina production equipment

From the perspective of chemical unit operation, the operation of rotary kiln is how to reasonably deal with the heterogeneous heat and mass transfer process of solid and gas media. The operation of this process requires high technology. Because of many factors, it is more difficult to operate than the heterogeneous heat and mass transfer process between gas and liquid.

The rotary kiln is a rotary cylinder with a small inclination angle with the horizontal line. When the cylinder rotates, the materials in the cylinder will turn up and down along with the cylinder drive, and then move forward gradually. The material is moving forward. When the material moves forward, it will turn over continuously, and the gas in the kiln will contact with the newly turned material continuously to carry out the heterogeneous heat and mass transfer operation.

Performance characteristics of alumina rotary kiln

1. Reduce energy consumption

Compared with the same grade alumina rotary kiln, the output increases by 50% and the energy consumption decreases by 30%. 2. Alumina rotary kiln is a kind of metallurgical chemical kiln. It can also be used for magnetization roasting of lean iron ore in iron and steel plant, oxidation roasting of chromium and nickel iron ore, roasting of high metallurgical gold ore and clinker of aluminum plant, aluminum hydroxide, chromium ore sand and chromium ore powder roasted by chemical plant.

3. Reliable operation

Alumina rotary kiln has solid structure, stable operation, high quality of kiln products, and can provide users with advanced high-efficiency vertical tube preheater and five-stage cyclone preheater.

4. Output and energy consumption

Compared with the traditional equipment, the operation rate of alumina rotary kiln is increased by 10%, the output is increased by 5% - 10%, and the heat consumption is reduced by 15%.