What is the main working principle of lime vertical kiln equipment
The working principle of a lime vertical kiln is based on the calcination and decomposition reaction of limestone, which decomposes calcium carbonate in limestone into calcium oxide (quicklime) and carbon dioxide through high-temperature calcination. This process is not only widely used in the production of auxiliary raw materials in the metallurgical industry, but also plays an important role in multiple fields such as construction and chemical engineering.
The lime vertical kiln has a vertical cylindrical shape, compact structure, easy operation, and high production efficiency. It mainly consists of key components such as kiln shell, refractory brick lining, insulation layer, combustion system, ventilation system, limestone loading system, unloading system, and control system. The kiln shell, as the main structure, is welded from steel plates and has good strength and sealing properties. The refractory brick lining laid internally is used to withstand high temperatures and resist the erosion of limestone, while the insulation layer is located on the outside of the refractory brick lining to reduce heat loss and improve thermal efficiency.
The working principle of lime vertical kiln follows the principle of counter current heat transfer. In the kiln, materials move from top to bottom, while flue gas passes through the entire column from bottom to top. Limestone raw materials undergo three stages of preheating, calcination, and cooling in the kiln. The raw material block size has strict requirements for entering the kiln, generally 25150mm, and needs to be graded and loaded into the kiln to ensure that the ratio of maximum block size to minimum block size does not exceed 23. During the preheating stage, limestone absorbs the heat from the rising hot gas inside the kiln, causing the temperature to gradually increase and the moisture to begin evaporating. As limestone continues to rise and enter the calcination zone, it undergoes decomposition reactions under high temperature, producing calcium oxide and carbon dioxide. After calcination, the lime is cooled by heat exchange with cold air in the cooling zone and discharged outside the kiln through the discharge device.
The combustion system is the core part of a lime vertical kiln, including burners, combustion chambers, and fuel supply devices. The fuel is mixed with air under the action of the burner and sprayed into the combustion chamber for combustion, producing high-temperature flames and providing necessary heat for the calcination of limestone. The ventilation system includes air inlet, exhaust outlet, and flue, ensuring air circulation inside the kiln, supporting the combustion process, and discharging the exhaust gas and heat generated by combustion. The flue connects the exhaust outlet and dust removal equipment to ensure that the exhaust emissions meet environmental requirements.
The limestone loading system is responsible for feeding limestone into the kiln, while the unloading system is located at the bottom of the kiln and discharges calcined quicklime from the kiln through rotation or vibration. These two systems work together to ensure continuous production and efficient utilization of limestone in the kiln. The control system automatically adjusts the fuel supply and burner operating status based on the type of fuel and kiln temperature to maintain a stable calcination temperature.
Temperature control is particularly crucial in the production process of lime vertical kilns. High temperature can completely decompose limestone, but excessive temperature may lead to a decrease in the quality of lime. Therefore, adopting advanced temperature control technology and heat recovery system can improve heat utilization efficiency, reduce energy consumption, and ensure lime quality.
The main working principle of the lime vertical kiln equipment is to decompose limestone into quicklime and carbon dioxide through high-temperature calcination, which involves three stages of preheating, calcination, and cooling, and achieves efficient and stable production through the collaborative work of various systems.
