What kind of refractory bricks are best for lining cement rotary kiln decomposition furnace and tertiary air duct?
1. Depends on the size of the stove
The refractory bricks used for lining the cement rotary kiln decomposition furnace and the tertiary air duct are related to the size of the furnace. Some use high alumina bricks or silica mullite bricks, and some use high-strength alkali-resistant bricks.
2. Which type of refractory brick should be used for the two parts?
So which kind of brick should be used for these two parts? The service life used is molysil silica bricks, and the 1550 silica molybdenum bricks used in the decomposition furnace can last for more than three years.
Of course, there are also manufacturers that use high alumina bricks and anti-flaking alumina bricks. To use alumina bricks, refractory bricks with an aluminum content of more than 70% must be used. However, spalling often occurs when used in these two parts. The usage time is generally about one year. If anti-flaking high-alumina bricks are used, the use period will be relatively long, but the prices of the two bricks will be very different. Because the zirconium component is added to the anti-flaking high alumina fire bricks, the price of zirconium is very high, which virtually increases the price of the anti-flaking high aluminium bricks.
3. High-strength alkali-resistant bricks can be used
There are also high-strength alkali-resistant refractory bricks. The tertiary air duct can still use high-strength alkali-resistant bricks, because the alkali resistance of alkali-resistant bricks is more suitable for this part. However, it is more suitable to use anti-flaking high alumina bricks or 1550 silica mullite bricks for the decomposition furnace because of its long service life.
If high-strength alkali-resistant bricks and high-aluminum bricks are used in these two parts, the service life of high-strength alkali-resistant bricks will be longer than that of high-aluminum bricks. The reason is that the alkali resistance of high-strength alkali-resistant bricks will not cause the lining bricks to peel off. , and the use of high alumina firebricks will often peel off under alkali erosion. As a result, the use time is short, resulting in frequent replacement, which increases the use cost.
4. It is more common to use 1550 silica mullite bricks
At present, 1550 silica molybdenum bricks are mostly used in the tertiary air ducts and decomposition furnaces of cement rotary kilns. A certain proportion of silicon carbide is added to the silica molybdenum bricks, which have strong wear resistance and corrosion resistance and can be used for more than three years. Avoid unnecessary trouble in terms of time and cost caused by replacing the lining multiple times.
5. It is better to use Silica Mullite Brick
High alumina bricks cannot be selected because of the price difference between silicon molybdenum bricks and high alumina firebricks. Repeated replacement of high aluminium bricks will increase production costs. Therefore, comparing the use of these refractory bricks, it is better to use silica molybdenum bricks for decomposition furnaces and tertiary air ducts.
