The process of tabular alumina

The basic process of tabular alumina production is ball milling, balling, drying and sintering.

(1) Ball mill. Lightly burned alumina powder by Bayer method is used as raw material for continuous ball milling. The fineness and specific surface area must meet certain requirements, which is conducive to the sintering and densification of alumina powder.

(2) into a ball. The finely ground powder is made into a ball or a ball into a ball. The formed green ball needs to have a certain strength to avoid breaking during transportation to the dryer. In view of the high moisture content of semi-finished balls, easy delamination, and difficulty in drying in the process of ball formation, the corresponding process optimization design is carried out and properly solved.

(3) Drying. The formed green balls enter the dryer, and use the countercurrent hot air in the shaft kiln to dry to remove about 15% of the moisture. However, the temperature in the shaft kiln should be strictly controlled to avoid cracks and delaminations in the billet balls, or even agglomeration and furnace blockage, which will eventually cause the interruption of the ball flow and the deterioration of the drying quality.

(4) Sintering. The green balls enter the shaft kiln after drying. The sintering temperature is 1900~-1950℃. By controlling the temperature and flow rate of hot air in the shaft kiln, a fully developed and completely sintered tabular alumina structure is obtained. After sintering, it can be cooled, selected (to pick out over-fired and under-fired products), inspection (physical and chemical index detection of fully sintered products), crushing and sieving, products with different particle sizes can be obtained.