How to extend the service life of refractory materials in rotary kilns?

How to extend the service life of refractory materials in rotary kilns?

How to extend the service life of refractory materials in rotary kilns?

Refractory materials are an important component of cement rotary kilns, embedded inside the kiln barrel. Their main function is to lower the temperature of the barrel, reduce heat loss, and prevent direct contact between the clinker and the barrel during the calcination process, thereby extending the service life of the rotary kiln. Therefore, fire-resistant materials are very important in the composition of the rotary kiln. However, in the actual production process, the comprehensive factors such as mechanical load, thermal load, and chemical erosion affect the service life of refractory materials, resulting in short and premature damage. Therefore, how to extend the service life of refractory materials, reduce the amount of refractory materials used and the production cost of enterprises, and improve product quality through technical means is of unanimous concern to cement enterprises.

Factors affecting the lifespan of refractory materials:

1. The influence of mechanical stress on the service life of refractory materials

Mechanical stress refers to the internal forces that interact with an object when it undergoes deformation due to external factors, in order to resist this change and restore the object to its original position. When the mechanical stress borne by the refractory bricks inside the kiln exceeds the value they can withstand, the refractory bricks will be damaged under the action of mechanical stress.

2. The influence of thermal stress on the service life of refractory materials

Thermal stress refers to the stress caused by the mutual constraint between the interior and exterior of an object when a temperature difference is formed, which prevents it from contracting freely. Acting on refractory materials, causing damage, is also an important cause of refractory material damage.

3. The impact of production operations on the service life of refractory materials

Excessive calcination temperature inside the kiln can also cause damage to refractory materials. In addition, the working temperatures of the transition zone, firing zone, cooling zone, kiln head cover, throat of the cooling machine, and outside of the nozzle are also relatively high, which can affect the service life of refractory materials. In addition, the rapid rotation of the kiln can also cause damage to refractory materials.

Technical measures to extend the service life of refractory materials:

1. In production operations, it is necessary to strictly control the deviation of the kiln axis so that it does not exceed 3mm. Once it exceeds 3mm, corrective measures must be taken.

2. Determine a reasonable size of the circumferential seam to reduce the impact of thermal stress.

3. Determine the calcination temperature based on the properties of the material.

4. During the production process, select a suitable rotational speed for the kiln body based on the amount of materials, size of clinker, and growth status.