Chrome-alumina refractories are a type of refractory material that exhibit excellent resistance to thermal shock, high temperature, and corrosion. They are composed of a mixture of chrome oxide and alumina, which gives them unique properties. These refractories are widely used in various high-temperature applications such as steel and non-ferrous metal industries, cement kilns, glass manufacturing, and petrochemical plants. One key characteristic of chrome-alumina refractories is their high refractoriness, enabling them to withstand extreme temperatures up to 1800°C. They also possess excellent mechanical strength, chemical stability, and resistance to acidic and basic environments. This makes them suitable for applications where exposure to harsh chemical environments or rapid temperature changes is common. Additionally, chrome-alumina refractories have low thermal conductivity, which helps to prevent heat loss and maintain a stable temperature profile within furnaces and kilns. Their dense structure and low porosity contribute to their exceptional thermal insulation properties. In terms of applications, chrome-alumina refractories are commonly utilized in blast furnaces, where they line the hot zones and withstand the high temperatures and corrosive gases produced during iron and steel production. They are also used in glass melting furnaces, where they provide excellent resistance to molten glass and prevent contamination. In the cement industry, chrome-alumina refractories are employed in the rotary kilns to withstand the extreme heat and chemical reactions involved in cement production. Overall, chrome-alumina refractories are highly valued for their exceptional thermal and chemical resistance, making them essential in high-temperature industrial processes that demand durability, longevity, and reliability.

Zirconia enhances the corrosion resistance of refractories by forming a protective layer on the surface of the refractory material. This layer acts as a barrier, preventing corrosive substances from penetrating the refractory and causing damage. Zirconia's high melting point and chemical stability make it an excellent choice for improving the corrosion resistance of refractories in various industrial applications.

Fire clay has several advantages when used in refractories. Firstly, it has a high melting point, allowing it to withstand extreme temperatures without significantly deforming. This makes it suitable for applications in industries such as steelmaking, where high temperatures are involved. Secondly, fire clay has excellent thermal insulation properties, effectively preventing heat transfer and reducing energy loss. Lastly, fire clay is relatively abundant and cost-effective, making it a popular choice for refractory materials. However, fire clay also has its limitations. One major limitation is its susceptibility to thermal shock. Rapid changes in temperature can cause fire clay to crack or break, reducing its durability and lifespan. Additionally, fire clay refractories have a lower resistance to chemical corrosion compared to other refractory materials. This restricts their use in environments with high chemical exposure, such as the petrochemical industry. In conclusion, fire clay offers advantages such as high melting point, thermal insulation, and cost-effectiveness. Nonetheless, its limitations in terms of thermal shock resistance and chemical corrosion susceptibility need to be considered when selecting refractory materials for specific applications.

The refractory raw materials commonly used in lining boilers include fire clay, high alumina, silica, and magnesite.