Reasons for deviation of lime mixed firing vertical kiln
Lime co firing vertical kiln plays an important role in industrial production, but the occurrence of kiln bias has brought many difficulties to production. Deviation from the kiln not only leads to uneven temperature distribution inside the kiln, affecting the quality of lime calcination, but also may cause a series of safety hazards. Therefore, it is crucial to identify the causes of kiln deviation and take effective prevention and solution measures.
Reasons for biased kiln
（1） Uneven quality of raw materials
Large differences in particle size of limestone
If the particle size of limestone entering the kiln is uneven, small particles are prone to premature decomposition in the kiln, while large particles decompose slowly. This will result in inconsistent reaction rates of materials inside the kiln, leading to deviation from the kiln.
Fluctuations in limestone composition
The changes in calcium carbonate content, impurity types, and content in different batches of limestone can lead to differences in their decomposition temperature and reaction characteristics. When limestone with unstable composition is calcined in the kiln, it is easy to cause local temperatures to be too high or too low, leading to kiln deviation.
（2） Uneven fabric
Unreasonable feeding method
During the feeding process, if the feeding points are concentrated or unevenly distributed, it will lead to different degrees of material accumulation and density in the kiln. Areas with thick material accumulation have high ventilation resistance and insufficient combustion; However, in areas with thin accumulations, excessive ventilation leads to rapid heat dissipation, which in turn leads to biased kilns.
Fabric equipment malfunction
Malfunctions in fabric equipment such as rotary feeders, bell feeders, etc., such as uneven rotation and blockage of fabric outlets, can cause materials to not be evenly distributed on the kiln section, resulting in deviation from the kiln.
（3） Improper ventilation control
Uneven distribution of air volume
Unreasonable design of ventilation systems, blockages in air ducts, valve failures, etc., can lead to uneven distribution of air volume in different parts of the kiln. Areas with excessive air flow experience severe combustion and high temperatures; Insufficient combustion and low temperature in areas with low air flow can lead to kiln deviation.
Unstable wind pressure
The unstable operation of the fan, with varying wind pressures, can affect the stability and uniformity of the airflow inside the kiln. Excessive wind pressure may cause some materials in certain areas to be blown up, leading to excessive local ventilation; If the wind pressure is too low, it will cause poor ventilation in certain areas, ultimately leading to deviation from the kiln.
（4） Structural defects in the kiln body
Irregular kiln body masonry
During the masonry process of the kiln, if the size of the brick joints is inconsistent and the masonry is uneven, it will affect the uniform distribution of air flow inside the kiln. The airflow in irregular areas is prone to forming vortices and resistance, leading to poor local ventilation and causing deviation from the kiln.
Kiln lining damage
During long-term use, the kiln lining may experience localized damage due to factors such as high temperature, chemical erosion, and mechanical wear. Damaged kiln lining not only affects the insulation effect, but also changes the airflow and heat distribution inside the kiln, leading to deviation from the kiln.
（5） Poor operational management
Improper control of calcination temperature
The operator failed to accurately control the calcination temperature based on the characteristics of the raw materials and the situation inside the kiln. If the temperature is too high or too low, it will affect the decomposition rate and reaction process of the materials, leading to uneven reaction of the materials inside the kiln and causing deviation from the kiln.
Improper operation of starting and stopping the kiln
During the process of starting and stopping the kiln, if the operation steps are improper, such as too fast heating and cooling speed, unreasonable air volume adjustment, etc., it will cause uneven thermal and mechanical stress on the materials and structure inside the kiln, leading to kiln deviation. （6） Other factors
Changes in meteorological conditions
For example, sudden changes in meteorological conditions such as strong winds and sudden drops in temperature may affect the ventilation environment outside the kiln, thereby affecting the ventilation and temperature distribution inside the kiln, leading to deviation from the kiln.
Detection equipment error
If there are errors or malfunctions in the detection equipment used to monitor parameters such as temperature, pressure, and air volume inside the kiln, it can lead to inaccurate information obtained by operators, making it difficult to detect and adjust kiln deviation in a timely manner.
The deviation of lime co firing vertical kiln is caused by multiple factors working together. To solve the problem of kiln deviation, it is necessary to start from multiple aspects such as raw material management, equipment maintenance, operation standards, and process optimization, and take comprehensive measures. At the same time, strengthening daily monitoring and maintenance, timely detecting and dealing with early signs of kiln deviation, is also the key to ensuring stable operation of the vertical kiln, improving lime quality and output.
