The lime vertical kiln body is divided into several zones
As an important equipment for producing lime, the reasonable division of the kiln structure plays a crucial role in the calcination process of lime. Understanding which zones the lime vertical kiln body is divided into can help better grasp the production process of lime and optimize the operating efficiency of the kiln.
1、 Pre tropical
Location and Function
The preheating zone is located at the upper part of the lime vertical kiln. When limestone and fuel are added from the top of the kiln, they first enter the preheating zone. Here, the high-temperature exhaust gas rising inside the kiln is used to preheat the materials, gradually increasing the temperature of limestone and fuel to prepare for the subsequent calcination process.
characteristic
The temperature in the subtropical zone is relatively low, usually around a few hundred degrees Celsius. Due to the presence of a certain amount of heat in the exhaust gas, the temperature of limestone and fuel can be raised to near the calcination temperature through heat exchange, thereby reducing the energy required for subsequent calcination processes. At the same time, the airflow velocity in the preheating zone is relatively slow, which is conducive to the full preheating of materials.
2、 Calcination belt
Location and Function
The calcination zone is the core area of the lime vertical kiln, located in the middle of the kiln body. In this area, limestone undergoes decomposition reactions at high temperatures, producing calcium oxide (lime) and carbon dioxide. The fuel burns here, providing the heat required for limestone decomposition.
characteristic
The temperature of the calcination zone is very high, usually above 1000 ℃. To ensure the complete decomposition of limestone, it is necessary to maintain a stable high-temperature environment. At the same time, the airflow velocity in the calcination zone is fast to ensure that the fuel can be fully burned and provide sufficient heat. In addition, the refractory materials of the calcination zone need to have good high temperature resistance and corrosion resistance to ensure the long-term stable operation of the kiln.
3、 Cooling belt
Location and Function
The cooling zone is located at the lower part of the lime vertical kiln. After the lime is decomposed in the calcination zone, it enters the cooling zone for cooling. Here, by exchanging heat with the cold air entering from the bottom of the kiln, the temperature of lime gradually decreases for easier discharge and storage.
characteristic
The temperature of the cooling zone gradually decreases from near the calcination temperature to near room temperature. The airflow velocity of the cooling belt is relatively fast to improve cooling efficiency. Meanwhile, in order to prevent excessive cold air from entering the kiln and affecting the calcination process, the cooling belt usually adopts a sealed structure to reduce air leakage.
4、 The interrelationship between the various zones of the kiln body
Heat transfer
The preheating zone utilizes the heat from the exhaust gas discharged from the calcination and cooling zones to preheat the materials, achieving the recovery and utilization of heat. The calcination zone is the main area where heat is generated, and the high temperature generated by fuel combustion decomposes limestone. The cooling belt carries away the heat of lime through heat exchange with cold air, while also providing some heat for the preheating zone.
Material flow
After the material is added from the top of the kiln, it passes through the preheating zone, calcination zone, and cooling zone in sequence. During this process, the temperature of the material gradually increases and then gradually decreases. The material flow between each belt needs to be stable to ensure continuous production of the kiln.
The lime vertical kiln body is mainly divided into three zones: preheating zone, calcination zone, and cooling zone. Each region has its unique role and characteristics, and they work together to complete the lime production process. Understanding the zoning of the kiln body helps to better understand the working principle of the lime vertical kiln, providing a basis for optimizing production processes and improving the operational efficiency of the kiln.
