Use of New Process for Refractory Casting of Cement Rotary Kilns

Nowadays, many cement rotary kiln users increase the rotational speed of the rotary kiln greatly by 3 to 4 times for the production of cement. The working temperature is high, the heat load is large, the raw material composition is easy to change, and harmful components such as alkali metals, sulfur and chlorine evaporate. The large amount of condensation, resulting in serious alkali corrosion. Therefore, this type of kiln requires high quality and quality of refractory materials and should be seriously faced.

In the traditional cement rotary kiln, the monolithic refractories are mainly used in the front and rear kiln mouths and the wet kiln chain belts. The varieties include: high-aluminum refractory castables and steel drilled reinforced refractory castables.

The refractory lining of rotary kiln kiln is the weak link of kiln lining, especially the front kiln refractory lining, the use temperature is about 1100°C, and it needs to withstand quenching, rapid thermal airflow impact, high temperature cement clinker wear and high temperature harmful gas alkali corrosion, etc. The conditions of use are very harsh. The main damage of the lining is: cracking, spalling and abrasion, so the refractories must have good thermal shock resistance, wear resistance and alkali resistance.

When the cylinder of rotary kiln kiln is not deformed, it is generally mashed with anti-peeling high alumina bricks, spinel bricks, and direct fused magnesia chrome bricks, etc., and high-quality mud is used as joint material in order to form a whole and prevent bricks from falling out. , increase life expectancy. However, the deformation of the cylinder is widespread. Therefore, the refractory castable is used for watering, the steel shell is welded with rivets, the castables are filled with steel fiber reinforced refractory castables, and the construction and baking are performed according to the regulations to meet the kiln shell lining. Production needs.

In short, the material composition of refractory castables for rotary kiln mouths should be determined according to the conditions of use, and ensure the in-situ reaction, sinterability and volume stability between matrix materials, so as to obtain good bending strength and thermal shock resistance. And corrosion resistance. At the same time, appropriate addition of additives (materials), and a reasonable choice of its type and dosage, can improve the material's construction performance and performance.