What is the reason for the return of alkali and white frost of high alumina refractory bricks?
The analysis of the reasons why high alumina refractory bricks return to alkali and become hoarfrost is as follows:
1. Influence of raw materials: High-alumina refractory bricks will return to alkali at high temperatures because their raw materials contain soluble salts. These salts decompose at high temperatures and release alkaline oxides. They are like "correction fluid" on the bricks, causing your beautiful brick surfaces to instantly become frosty. Therefore, when we choose high alumina bricks, we must carefully check the raw materials to prevent being raided by these "correction fluids"!
2. Influence of firing temperature: The firing process of high alumina refractory bricks is very critical. If the temperature is not high enough or the time is not long enough, some soluble salts may not be completely decomposed. These "stubborn elements" will lurk inside the brick, and then gradually separate out during later use, forming an unpleasant white frost. Therefore, in order to prevent the appearance of hoarfrost, we must accurately control the firing temperature and time to ensure that all soluble salts can be completely decomposed. In this way, our high-alumina refractory bricks can always remain beautiful and efficient!
3. Effect of moisture: During transportation, storage and use of high alumina refractory bricks, special care must be taken to avoid contact with moisture, especially water containing salts. These "salty" water molecules will accumulate on the surface of the brick and react with the alkaline substances in the brick to form white frost. This is like putting a "white robe" on Brick, causing it to instantly lose its original charm. Therefore, in order to maintain the beauty and performance of high-alumina refractory bricks, we must take careful care of it!
4. The influence of atmosphere: The atmosphere in the kiln is the "mood regulator" of high alumina refractory bricks. If the atmosphere is too "excited" and the oxidizing atmosphere is too heavy, some components in the brick will be "frightened" and undergo oxidation reactions. This is like a "chemical riot" inside the brick, producing alkaline oxides. These oxides will accumulate on the surface of the bricks, causing alkalinization. Therefore, in order to maintain the stable working condition of high-alumina refractory bricks, we must learn to control the atmosphere in the kiln to keep it mild and pleasant!
