Refractories and cement process are inseparable as a whole. The operation cycle of refractories determines the completion rate of the kiln process system operation index, while the stable operation of the kiln system is the basis for guaranteeing the life of refractories, and the two complement each other. Therefore, to ensure the safe and efficient operation of the rotary kiln system, the following links should be grasped in the use of refractory materials.
1、The problems to pay attention to when opening and stopping the kiln
Kiln barrel heat expansion can partially compensate for the expansion rate of kiln bricks, but this is the role of the thermal equilibrium conditions occur. Therefore, when igniting and drying the kiln, the kiln should run slowly so that the temperature of the kiln barrel rises slowly, so that the compensating effect of the kiln barrel can be played. Each plant can customize the appropriate temperature rise curve for its kiln type and refractory type to ensure long-term stable operation of the refractory. In terms of stopping the kiln to keep warm when not ready to change bricks, especially in an accident state, all want to cool down as soon as possible (including the cooler, preheater system accident) to go in for maintenance, but the refractory bricks are damaged due to the rapid cooling. This, on the contrary, is not worth the loss, this should be fully considered and attention, so to carefully implement the ignition heating and cold kiln system.
2、Keep the equipment long-term stable operation
Long-term stable operation of the equipment is the basis for the strict implementation of the ignition heating system and kiln cooling system, if each time the ignition heating can run normally for a long time, then the time and cost spent on ignition heating will become insignificant. However, if the equipment is not in good condition and the kiln is stopped several times a month, it is impossible to strictly implement the ignition heating and cooling system. Because of frequent kiln stoppages, which will inevitably lead to damage to the brick destruction, it can be seen in the use of refractory bricks, equipment is also in the basic position.
3, Give full play to the role of the kiln skin
Kiln skin on the refractory brick protection role is very obvious. First of all, it can reduce the internal stress caused by the temperature difference in the refractory brick, such as no kiln skin protection, refractory brick is very easy due to the brick temperature difference stress is too large and blowing off; secondly, it can reduce the chances of chemical erosion of refractory brick, if no kiln skin protection, clinker in the liquid phase, molten salt, gas in the alkali, chlorine, sulfur and other substances and carbon monoxide will erode the brick, so that the brick surface structure deterioration is vulnerable to damage; again it can slow down the magnitude of thermal shock. Again it can slow down the magnitude of the thermal shock, kiln skin since it is a barrier, naturally also is the kiln temperature fluctuations in the buffer layer, kiln temperature fluctuations in a certain range, through the kiln skin to the brick surface has very little impact, even if the parking cold kiln and ignition heating period, due to the existence of the kiln skin, slowing down the brick hot surface heating speed, reduce the expansion rate, therefore, the kiln skin is more intact when the ignition heating can be properly accelerated, and at the same time due to The protection of the kiln skin, brick thermal fatigue degree will also be significantly reduced.
This shows that hanging and maintaining a good kiln skin to extend the use of refractory bricks cycle is essential.