Precautions for watching the fire during calcination in a vertical lime kiln
In the calcination process of a vertical lime kiln, observing the fire is a crucial task that directly affects the quality and production efficiency of lime. The following are precautions for observing the fire during calcination in a vertical lime kiln.
1、 Flame color and temperature judgment
Flame color under normal circumstances
During normal calcination in a vertical lime kiln, the flame should present a bright light yellow to orange color. This color indicates that the temperature inside the kiln is within an appropriate range, the fuel is fully burned, and the decomposition reaction of limestone is also proceeding normally. When the flame color approaches white, it indicates that the temperature inside the kiln may be too high and there is a risk of overburning. At this point, it is necessary to closely monitor and take corresponding measures, such as reducing the supply of fuel appropriately to prevent the quality of lime from deteriorating due to overburning.
The meaning of abnormal flame color
If the flame appears dark red or black, it often indicates insufficient combustion. Perhaps due to poor ventilation and insufficient oxygen supply, the fuel cannot burn completely. This situation can affect the uniformity of temperature inside the kiln and the decomposition effect of limestone, and may also produce harmful gases such as carbon monoxide. At this time, it is necessary to check whether the ventilation equipment is operating normally, such as whether the air volume of the fan is sufficient, whether the air duct is blocked, and adjust and clean it in a timely manner.
2、 Observation of material conditions inside the kiln
Decomposition state of limestone
By observing the color changes of limestone inside the kiln, its decomposition state can be determined. During the calcination process, as the temperature increases, limestone will gradually change from its original gray color to white. When most of the limestone appears white in color, it indicates that the decomposition is basically completed. If it is found that some areas of limestone still have a darker color, there may be uneven calcination, and the distribution of fuel or ventilation needs to be adjusted to ensure that limestone can be fully decomposed.
Movement and stacking of materials
In a vertical kiln, materials move slowly from top to bottom. Pay attention to observing whether the movement of materials is smooth and whether there is any accumulation phenomenon. If materials accumulate in a certain part of the kiln, it will affect the flow of air and the heat transfer effect, causing local temperatures to be too high or too low, which will affect the quality of lime. If material accumulation is found, it may be due to fast feeding speed or malfunction of the discharge device, and it is necessary to adjust the feeding amount or repair the discharge equipment in a timely manner.
3、 Pressure and atmosphere control inside the kiln
Stability of pressure
The stability of kiln pressure is crucial for the calcination process. Generally speaking, a slight positive pressure should be maintained inside the kiln to prevent a large amount of cold air from entering the kiln and affecting the temperature and atmosphere inside. Firefighters need to closely monitor the readings of pressure gauges and promptly identify the cause when there are fluctuations in pressure. For example, if the pressure suddenly drops, it may be due to air leakage in the kiln body, which needs to be checked and repaired in a timely manner to maintain a suitable pressure environment inside the kiln.
Adjustment of Atmosphere
A suitable kiln atmosphere is beneficial for the decomposition of limestone and the improvement of lime quality. Ensure sufficient oxygen supply in the kiln to ensure full combustion of the fuel. At the same time, attention should be paid to controlling the content of carbon dioxide, as the decomposition of limestone produces a large amount of carbon dioxide. If too much carbon dioxide accumulates, it will affect the combustion efficiency of fuel and the decomposition rate of limestone. The atmosphere inside the kiln can be controlled by adjusting the ventilation volume to ensure that the calcination process is carried out in a suitable atmosphere.
4、 Safety precautions for fire operation
Personal protection
Firefighters must wear appropriate protective equipment such as heat-resistant gloves, protective goggles, and face shields when performing firefighting operations. Because during the process of observing fire, there may be dangerous factors such as high temperature radiation and splashing materials. At the same time, it is necessary to wear work clothes that meet safety requirements to avoid clothing being ignited or caught in equipment.
Equipment safety
Before watching the fire, make sure that the viewing holes, observation windows, and other equipment are intact and well sealed. If these devices are damaged or poorly sealed, it may cause flames to spray out or cold air to enter the kiln, affecting the calcination process. At the same time, it is necessary to regularly inspect and maintain the fire monitoring equipment to ensure its normal operation and safe use.
5、 Data recording and analysis
Detailed records
Firefighters should record in detail various data during each fire inspection, including flame color, kiln temperature, pressure, material conditions, etc. These data are crucial for analyzing the stability and quality control of the calcination process. Through long-term data recording, potential problems and patterns can be discovered in order to adjust production processes in a timely manner, improve lime quality and production efficiency.
Data analysis and improvement
Regularly analyze the recorded data, compare the changes in data over different time periods, identify problems and directions for improvement during the calcination process. For example, if it is found that the temperature inside the kiln fluctuates significantly during a certain period of time, it may be caused by unstable fuel quality or ventilation system failure through analysis, and then targeted measures are taken to improve and ensure the stability and optimization of the calcination process.
During the calcination process in a vertical lime kiln, observing the fire requires a high sense of responsibility and professional skills. Only by strictly following the precautions for fire inspection, closely monitoring various situations inside the kiln, adjusting and handling problems in a timely manner, can we ensure the normal operation of the lime kiln and produce high-quality lime products.
