When the rotary kiln is in operation, if the thermal system is not stable, the lining material of the kiln will be suddenly cold and hot, the kiln skin will collapse for a long time, and the refractory brick will easily crack and peel off, which will greatly shorten the service life of the kiln. Therefore, corresponding measures should be taken to stabilize the thermal system

(1) The reasonable matching of air, coal, material and kiln speed is related to and restricted by each other. Only by adapting and matching each other can the thermal system be stable. The combination of air, coal, material and kiln speed should not only be reasonable in quantity, but also pay attention to the quality of medium, so as to make the pulverized coal burn fast, the material absorb heat quickly, and the kiln speed is appropriate, which can give full play to the advantages of the precalciner kiln. This requires reasonable adjustment to ensure that the air, coal and material mix evenly and adapt to the kiln speed, so as to achieve the separation of materials, good suspension state, complete combustion of pulverized coal, fast rotation of thin materials, high quality, high production and low consumption

(2) "Five stabilities and one stability" means that the composition of raw material entering the kiln is stable, the feed quantity into the kiln is stable, the fuel composition is stable, the fuel feeding quantity is stable and the equipment operation is stable. Only by realizing these "five stabilities" can the thermal system of rotary kiln system be stable.

(3) The multi-channel coal injection pipe must be reasonably and dynamically adjusted according to different coal quality and kiln conditions. On the premise of ensuring the good sintering condition of clinker, the proportion of axial flow air and swirling air should be adjusted according to the clinker granulation, flame shape, cylinder temperature, kiln tail temperature and pressure, so as to ensure that the flame shape and length are appropriate, smooth and powerful, and the kiln skin is stable Scour. Pay close attention to the influence of pulverized coal quality on flame shape. If the moisture content of coal is partial and the black fire head becomes longer, the coal injection pipe should be properly withdrawn to raise the secondary air temperature, increase the combustion speed and protect the kiln skin.

(4) The operation of grate cooler should be adjusted reasonably to ensure stable temperature of secondary and tertiary air and synchronous operation with rotary kiln, so as to stabilize thermal system.

To stabilize the thermal system of rotary kiln, in addition to the above points, attention should be paid to the correct operation of the kiln and later maintenance, which is helpful for the thermal system.