How to select refractory materials under the corrosion of high-temperature gases?
Due to the varying operating conditions of high-temperature kilns, the corrosive components in the combustion gases also differ, leading to various severe forms of erosion on the refractory materials in contact with them. Therefore, only by selecting the appropriate refractory materials based on specific usage conditions can we ensure a longer service life for the refractory materials. Here are the specific selection criteria:
Refractory Material Selection for Kilns with High CO Content in High-Temperature Gases
When the high-temperature gases in a kiln have a high CO content, non-oxide refractory materials are the ideal choice. Among them, C-SiC quality refractory materials stand out as the best option.
Refractory Material Selection for Kilns with Cl or/and HCl in High-Temperature Gases
When the high-temperature gases in a kiln contain Cl or HCl, or both, SiO?-Al?O? refractory materials can meet the usage requirements. However, it is essential to choose this type of refractory material with as low an FeO content as possible.
Refractory Material Selection for Cement Rotary Kilns Fueled by Waste Oil
In cemSiO?-Al?O? refractory materials can meet the usage requirements. However, it is essential to choose this type of refractory material with as low an FeO content as possible.
Refractory Material Selection for Cement Rotary Kilns Fueled by Waste Oil
In cement rotary kilns fueled by waste oil, the combustion gases contain a large amount of Cl? and SO?. In this case, MgO-Spinel refractory materials with high resistance to sulfur and chlorine erosion should be selected. Particularly, the third-generation MgO-Spinel(Al?O?) refractory materials manufactured using Spinel bonding reinforcement technology are recommended. These high-performance refractory materials are characterized by their use of high-quality Spinel (in-situ Spinel) combined with fused magnesia and fused Spinel, making them a high-tech MgO-Spinel(Al?O?) refractory material. They can enhance resistance to liquid phase erosion caused by overheating. Usage results show that these high-performance MgO-Spinel(Al?O?) refractory materials are particularly suitable for cement rotary kilns fueled by waste oil, as these kilns experience significant fluctuations in combustion value, leading to severe local erosion, and these refractory materials can significantly extend the service life of the kiln.
Refractory Material Selection for Lining in Contact with Alkaline and SO? High-Temperature Gases
For lining refractory materials that come into contact with alkaline and SO? high-temperature gases, such as the middle格子 brick in the regenerative chamber of a glass kiln, MgO-2MgO·SiO? refractory materials can be selected. This is because these refractory materials not only have a strong resistance to alkali sulfate erosion but are also relatively inexpensive. If further enhancement of erosion resistance is needed, MgO-ZrO·SiO? refractory materials can be chosen. This is because in these refractory materials, ZrO?·SiO? reacts with MgO at high temperatures to form 2MgO·SiO? and f-ZrO?, creating a continuous 2MgO·SiO?-ZrO? matrix phase with very strong erosion resistance.
Since the high-temperature gases in kilns contain highly corrosive components such as Cl?, HCl, SO?, and alkalis, which are highly penetrative, the selected refractory materials must possess advantages such as high density, low permeability, and good thermal shock resistance to adapt to such working environments.
Additional Suggestions on Refractory Material Selection:
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