How to prolong the service life of refractory materials for rotary kiln?
Refractory material is an important part of the cement rotary kiln. It is inlaid in the kiln shell of the rotary kiln, which is mainly used to reduce the temperature of the shell, reduce the heat loss, and prevent the clinker from directly contacting the shell during the calcination process, thus extending the service life of the rotary kiln. Therefore, fire-resistant materials are very important among the components of the rotary kiln. However, due to the influence of mechanical load, thermal load, chemical corrosion and other comprehensive factors in the actual production process, the service life of refractory materials is relatively short and damaged prematurely. Therefore, cement enterprises have paid close attention to how to extend the service life of refractory materials, reduce the consumption of refractory materials and the production cost of enterprises, and improve the quality of products through technical means.
Influencing factors of refractory life
1. Effect of Mechanical Stress on Service Life of Refractory
Mechanical stress refers to the internal forces that interact with each other when an object is deformed due to changes in external factors to resist such changes and restore the object to its original position. When the mechanical stress borne by the refractory brick in the kiln body exceeds the value that it can bear, the refractory brick will be damaged under the action of mechanical stress.
2. Influence of Thermal Stress on Service Life of Refractory
Thermal stress refers to the stress generated when the temperature difference is formed, which makes the internal and external parts of the object produce mutually constrained forces, so that they cannot completely shrink freely. It is also an important reason for the damage of refractory materials by acting on them.
3. Influence of Production Operation on Service Life of Refractory
Too high calcination temperature in the kiln will also cause damage to the refractory. In addition, the working temperature of transition zone, sintering zone, cooling zone, kiln hood, throat of cooler and outside of nozzle is also relatively high, which will also affect the service life of the refractory. In addition, the rapid rotation of the kiln will also cause damage to the refractory.
Technical Measures for Prolonging the Service Life of Refractory Materials
1. During production operation, the deviation of kiln axis shall be strictly controlled so that the kiln axis shall not exceed 3mm. Once the deviation exceeds 3mm, it shall be corrected.
2. Determine a reasonable size of circumferential seam to reduce the impact of thermal stress.
3. The calcination temperature shall be determined according to the properties of materials.
4. In the process of production and operation, select a suitable speed for the kiln according to the amount of materials, the size of clinker and the growth status.
——Author：ebico