- The active magnesium oxide is the magnesium oxide with hydration capacity.
- The formationof active magnesium oxide.
During calcining process, there are different temperature in ore roasting because the technology and other reasons. When the temperature achieves 400℃ to 600℃, magnesium oxide can present the highest activity. Because its interior structure is loose, and the hole between crystals is highest.
When the temperature achieves 750℃to 850℃, the porosity between crystals decreases, and achieves the optimal range of magnesium cement reaction. What’s more, the activity is medium. When the temperature achieves 900℃to 1000℃, it forms the dead burned magnesia. The activity is very low even have none. Within a certain range of activity, the product with high activity has a better quality, and the product with low activity has a worse quality. However, the underburnt magnesium oxide was not the case. The activity of it is higher, the reaction is more intense, the heat release of magnesium oxide is more centralized. Therefore, the product added it has a lower quality, and is easy to crack with low strength.