What are the reasons for the upward movement of the calcination zone in the lime kiln
Lime shaft kiln is currently a mature industrial lime kiln technology. During the calcination process, various problems may occur due to operational reasons, such as the upward movement of the calcination belt, which is a very common operational fault. Understanding the causes of these faults can help us better operate the lime kiln, avoid faults, and prevent the lime kiln distributor from being burned out.
The main reason for the upward movement of the calcination belt is:
1. The fuel particles loaded into the kiln are too small. Fuel is the source of heat for calcining limestone to produce lime. Lime vertical kilns have certain requirements for the particle size of fuel, generally requiring particles between 15-40mm. This particle requirement is to ensure a more uniform mixing of fuel and limestone raw materials. At the same time, it also ensures that the fuel will not burn prematurely. If the fuel particles entering the kiln are overheated, the fuel will burn prematurely in the preheating zone, raising the temperature of the preheating zone and increasing the calcination zone.
2. The amount of ash unloaded is too small. The unloading amount is too small, and the downward movement speed of the materials in the entire kiln slows down. Providing more time for the fuel to dissipate heat in the upper part of the kiln can cause the fuel to burn prematurely in the preheating zone, resulting in an upward movement of the calcination zone.
3. Excessive combustion air. The oxygen in the combustion air is a necessary condition for fuel combustion. When the air volume is too high and the oxygen supply is sufficient, the combustion reaction of the fuel will become abnormally intense, and the flame and high-temperature area will rapidly expand along the longitudinal (upward) direction of the kiln.
These are the operational reasons for the upward movement of the calcination zone in the lime kiln. It is necessary to timely understand the calcination status of the lime kiln, adjust it in a timely manner, avoid the upward movement of the calcination zone, and better ensure the quality of lime.
