Lime shaft kiln flue gas temperature
In the lime production process, the flue gas temperature of the lime kiln is an important parameter that has a significant impact on the efficiency, energy consumption, and environmental protection of the production process. Generally speaking, the flue gas temperature of lime shaft kiln is usually between 100-200 degrees.
1、 Characteristics of temperature range
（1） Relatively low temperature range
Compared with some high-temperature industrial furnaces, the flue gas temperature of lime vertical kilns is relatively low. This is determined by the production process characteristics of lime shaft kiln. During the lime firing process, the combustion of fuel and the decomposition reaction of limestone produce flue gas, which is carried out in a specific environment inside the shaft kiln, maintaining the flue gas temperature within the range of 100-200 degrees. This relatively low temperature not only ensures the smooth progress of the production process, but also reduces excessive energy consumption and equipment high-temperature losses to a certain extent.
（2） A certain degree of volatility
Although the flue gas temperature is roughly between 100-200 degrees, it is not a fixed value in the actual production process, but there may be some fluctuations. This is mainly influenced by various factors, such as the quality and composition of raw materials, the type and amount of fuel, the operating process of the shaft kiln, and ventilation conditions. For example, when the impurity content in the raw materials is high or the fuel combustion is insufficient, it may cause an increase or decrease in the flue gas temperature, thereby affecting the stability of the entire production process and product quality.
2、 Factors affecting flue gas temperature
（1） Raw material characteristics
The purity, particle size, and moisture content of limestone can all affect the temperature of flue gas. Limestone with high purity, uniform particle size, and moderate moisture content reacts more stably during the firing process, which can make the heat distribution more uniform and maintain a relatively stable flue gas temperature. On the contrary, if the quality of limestone is poor, it may lead to incomplete or uneven reactions, resulting in fluctuations in flue gas temperature.
（2） Fuel combustion situation
Fuel is a key factor in providing heat, and its degree of combustion is directly related to the flue gas temperature. The appropriate type of fuel and good combustion conditions can ensure sufficient combustion of the fuel, release enough heat, and maintain the flue gas temperature within a reasonable range. If the fuel supply is insufficient or the combustion is not sufficient, it will lead to insufficient heat, a decrease in flue gas temperature, and affect the quality and efficiency of lime firing.
（3） Vertical kiln operation process
The ventilation rate, feeding speed, and pressure inside the shaft kiln also have a significant impact on the flue gas temperature. Reasonable ventilation can ensure sufficient combustion of fuel and effective heat transfer, keeping the flue gas temperature stable. Excessive or insufficient feeding speed may disrupt the thermal balance inside the kiln, leading to fluctuations in flue gas temperature. In addition, changes in kiln pressure can also affect combustion and heat transfer processes, thereby affecting flue gas temperature.
3、 The significance of flue gas temperature
（1） In terms of production efficiency
The appropriate flue gas temperature is crucial for improving the production efficiency of lime. Within a certain range, a stable flue gas temperature can ensure the smooth decomposition reaction of limestone, shorten the firing time, and increase production yield. If the flue gas temperature is too high or too low, it will affect the reaction rate and reduce production efficiency.
（2） Energy Utilization and Environmental Protection
Reasonable control of flue gas temperature can help improve energy utilization efficiency and reduce energy consumption. Meanwhile, a lower and stable flue gas temperature can reduce the emission of pollutants such as nitrogen oxides. This is of great significance for protecting the environment and achieving sustainable development. In the lime production process, optimizing the process and equipment, controlling the flue gas temperature well, can achieve a win-win situation of economic and environmental benefits.
The flue gas temperature of lime shaft kiln between 100-200 degrees has its unique characteristics and influencing factors, and is of great significance to the production process. Deeply understanding and mastering the relevant knowledge of flue gas temperature plays an indispensable role in optimizing lime production process, improving production efficiency, and protecting the environment.
