What should we do? If the rotary kiln cylinder body locally generates high temperature
16 Apr,2020 UTC+8 Views:
Rotary kilns are commonly used in cement, lime, calcium carbonate and other materials for calcining a new type of equipment, generally using coal, gas, natural gas, etc. as a combustion path. However, due to the high temperature in the kiln, improper operation or untimely treatment, it will not only affect the service life of the rotary kiln, but also stop the kiln for maintenance in the eyes, increasing the maintenance cost of the enterprise!
How to deal with the high temperature locally in the rotary kiln shell? When the high temperature locally occurs in the rotary kiln, theoretically the red kiln must be stopped, but for some red areas of high temperature and small area, we adjusted the process parameters and added air cooling In this way, the temperature can be lowered, the kiln skin can be replenished, and the production can be continued, which greatly reduces the operating cost.
1. Treatment when the local high temperature is lower than 400 ℃
When the local temperature is high, but lower than 400 ℃, it means that the refractory brick has not completely fallen off, but it has become thinner. At this time, it is recommended to use a cooler or a high-pressure air pipe to cool, so that the temperature can be lowered, and then it can be reduced auxiliaryly. If the kiln speed is slow, there is no problem to make up the kiln skin.
2. Treatment when the local temperature is higher than 400 ℃
When the local temperature is higher than 400 ℃, the danger is relatively large, and the process parameters should be adjusted by a large margin. For example, the feeding amount of 2500t / d kiln can be reduced by 20 ～ 50t / h, so that the filling amount of the kiln is reduced, the flow cross-section of the air flow is increased, and the flame is smooth; Position the kiln skin as soon as possible; the amount of head coal can be reduced by up to 2 ~ 3t / h, but to ensure that the thermal system in the kiln is stable, to avoid running yellow powder; the head of the burner can be lowered by 10-20mm, so that The flame is closer to the material to reduce the burning of high temperature points. The cross section of the inner and outer cylinders can be adjusted to 50-60 mm, the ratio of the internal and external winds can be adjusted to 0: 100% -20%: 100%, and the burner can enter or exit the kiln The mouth is 0.4m, which makes the fire point position move forward or backward by a large margin.
In addition, a high-pressure air pipe and a cooling fan are used to cool the site, and the laboratory adjusts the raw material composition to increase the amount of liquid phase.
If the temperature rise and fall of local high temperature point is repeated and unstable, when it is determined that the position of the air pipe has not changed and the fan has not been stopped, the hydraulic gear wheel can be stopped to fix the kiln body at the lower limit of the channel, and then recalibrate the high temperature point position The air duct blows cold, thereby eliminating the possibility of high temperature point movement caused by the kiln body moving up and down. During the stop of the wheel, pay close attention to the change of the temperature of the supporting roller, and the time should not be too long. It should be opened in time after the temperature of the high temperature point is down.
In order to ensure the normal operation of the rotary kiln, Daily maintenance is very important, so the operator must test the barrel after the rotary kiln has been running for a period of time to ensure the wear status of various components in the kiln, make records, and prevent The failure occurred!
How to deal with the high temperature locally in the rotary kiln shell? When the high temperature locally occurs in the rotary kiln, theoretically the red kiln must be stopped, but for some red areas of high temperature and small area, we adjusted the process parameters and added air cooling In this way, the temperature can be lowered, the kiln skin can be replenished, and the production can be continued, which greatly reduces the operating cost.
1. Treatment when the local high temperature is lower than 400 ℃
When the local temperature is high, but lower than 400 ℃, it means that the refractory brick has not completely fallen off, but it has become thinner. At this time, it is recommended to use a cooler or a high-pressure air pipe to cool, so that the temperature can be lowered, and then it can be reduced auxiliaryly. If the kiln speed is slow, there is no problem to make up the kiln skin.
2. Treatment when the local temperature is higher than 400 ℃
When the local temperature is higher than 400 ℃, the danger is relatively large, and the process parameters should be adjusted by a large margin. For example, the feeding amount of 2500t / d kiln can be reduced by 20 ～ 50t / h, so that the filling amount of the kiln is reduced, the flow cross-section of the air flow is increased, and the flame is smooth; Position the kiln skin as soon as possible; the amount of head coal can be reduced by up to 2 ~ 3t / h, but to ensure that the thermal system in the kiln is stable, to avoid running yellow powder; the head of the burner can be lowered by 10-20mm, so that The flame is closer to the material to reduce the burning of high temperature points. The cross section of the inner and outer cylinders can be adjusted to 50-60 mm, the ratio of the internal and external winds can be adjusted to 0: 100% -20%: 100%, and the burner can enter or exit the kiln The mouth is 0.4m, which makes the fire point position move forward or backward by a large margin.
In addition, a high-pressure air pipe and a cooling fan are used to cool the site, and the laboratory adjusts the raw material composition to increase the amount of liquid phase.
If the temperature rise and fall of local high temperature point is repeated and unstable, when it is determined that the position of the air pipe has not changed and the fan has not been stopped, the hydraulic gear wheel can be stopped to fix the kiln body at the lower limit of the channel, and then recalibrate the high temperature point position The air duct blows cold, thereby eliminating the possibility of high temperature point movement caused by the kiln body moving up and down. During the stop of the wheel, pay close attention to the change of the temperature of the supporting roller, and the time should not be too long. It should be opened in time after the temperature of the high temperature point is down.
In order to ensure the normal operation of the rotary kiln, Daily maintenance is very important, so the operator must test the barrel after the rotary kiln has been running for a period of time to ensure the wear status of various components in the kiln, make records, and prevent The failure occurred!
