A study of the thermal decomposition of alunite is positively contributed to increase the efficiency of useful matter extraction from the ore.
The thermal decomposition of the ore must necessarily include both the effect of temperature of calcination and the time of heating at selected temperature.
From the experimental results,
1. The optimum temperature of the ore dehydration was 600 ℃ to 650 ℃.
2. The optimum heating time of the ore dehydration at 650 ℃ was 7 minutes to 10 minutes.
3. The optimum particle size of the ore was -100 mesh.
4. The rate equation of decomposition at 650 ℃ is as follows:
Where W is the amount of volatile matter decreased from the ore and a & b are constants.
5. With the calcination equipments as fluidized bed or pneumatic system, the heating time of calcination would be shortened.