Superior Application Properties of High Alumina Cement
High-performance high-alumina cement is a refractory material with superior properties. High-alumina cement is a mixture containing a large amount of aluminum that is made from bauxite and lime through a series of charcoal burning and high-temperature processes. Because it is similar to cement, it is also called aluminate cement. High alumina cement, due to different aluminum and calcium contents, is divided into CA-50, CA-70, and CA-80. This article mainly explains the superior properties of high alumina cement and its application advantages.
What are the Properties of High Alumina Cement?
CA-50 high alumina cement is yellow cement, and its raw materials are bauxite and limestone. CA-70 high alumina cement has less impurities, better setting properties and refractory properties than CA-50 refractory cement, and is used as a binder in the preparation of low-cement refractory castables. The aluminum content of CA-80 high alumina cement is 80%, and it contains α-AL2O3 micropowder, which is used as a binder in high-grade refractory castables. Because the cement aluminum content of CA-70 and CA-80 is high, it can improve the weak points of the setting speed and medium-temperature strength of refractory castables. And because of the low calcium content, the later strength of the refractory castables has a longer service life.
The higher the alumina content, the higher the refractoriness. The lower the alumina content, the higher the calcium oxide content. Add high alumina cement as a binding agent to demould the refractory castable within 24 hours. High alumina cement will affect the fluidity, construction, and demoulding time of refractory castables. If used improperly, it will have a great impact on the construction of refractory castables.
The use of high alumina cement is divided into three stages: dissolution, nucleation, and precipitation. For example, CA-50 high alumina cement is generally used in medium and low-grade refractory castables. CA-50 cement has the weakest strength at a temperature of 800°C. Therefore, if the operating temperature of the furnace lining is 800°C, which is also the most embarrassing temperature. If the temperature is not high, ordinary refractory castables cannot be used, and low cement castables must be used. Low cement castables contain low calcium, have good strength at medium temperatures, and have good strength in later use.
The high alumina cement of CA-70 and CA-80 contains high aluminum content and the addition ratio is small. Therefore, it is used in low-cement refractory castables to not only enhance the strength of the refractory castables but also reduce the calcium content of the refractory castables. It also improves the use of medium-temperature intensity.
Therefore, adding high alumina cement to refractory castables depends not only on the combination. Also, pay attention to the use temperature to determine whether to add CA-50 high alumina cement or CA-70 and CA-80 high alumina cement.
Application Advantages of High Alumina Cement
High alumina cement is in powder form before it becomes cement. Because it dissipates heat when exposed to water, it must be kept dry during storage. Try to isolate the air as much as possible to prevent deterioration. It is used in the preparation of unshaped refractory materials, as well as in the preparation of cement for special purposes such as gypsum alumina expanded cement and self-stressing cement. Because it can dissipate heat, it is also beneficial to the maintenance of cold-resistant projects, as well as projects with special needs such as rush construction, emergency repairs, resistance to sulfate corrosion, and winter construction.
High alumina cement has excellent high-temperature fire resistance and corrosion resistance. Therefore, it has a wide range of applications in the industrial field, mainly reflected in the following aspects.
1. Furnace building. High alumina cement can be used in the construction and maintenance of high-temperature kilns, such as cement kilns, alumina kilns, etc. In these high-temperature environments, high alumina cement can effectively resist high-temperature erosion and provide good fire resistance.
2. Refractory materials. High alumina cement can be used to produce various refractory materials, such as high-temperature bricks, castables, refractory cement, etc. These materials have good high-temperature corrosion resistance and can be used in construction in various high-temperature environments.
3. Oil well cement. High alumina cement can be used to produce oil well cement. This cement has high strength, and high-temperature corrosion resistance and can be used in various harsh underground environments.
4. Bauxite beneficiation. High alumina cement can be used in bauxite beneficiation processing. It acts as a binding agent, providing a high-strength solid compound that helps improve bauxite grade.
In short, high alumina cement is a very special cement. It has excellent high-temperature fire resistance and corrosion resistance and is widely used in construction and industrial manufacturing under various high-temperature and harsh environments.
Comments