What is the reason for the partial fire of lime shaft kiln
The partial fire of lime shaft kiln is a common and difficult problem in the process of lime production. It will not only affect the quality and output of lime, but also increase energy consumption and reduce the capacity of kiln. In depth analysis of the causes of partial fire can be discussed from the aspects of raw material factors, operation factors, equipment factors, fuel factors and gas distribution in the kiln.
Raw material factor
As the main raw material of lime shaft kiln, the composition, particle size and impurity content of limestone will directly affect the calcination process. If limestone contains high silicon, aluminum, iron and other impurities, these impurities will react with calcium carbonate to form compounds with low melting point at high temperature, resulting in nodulation and hanging in the kiln. These nodules and hanging materials will seriously affect the heat transfer and distribution, resulting in partial fire. In addition, the uneven particle size of limestone will also lead to uneven heat transfer, and the excessive particle size will make it difficult for heat to enter the interior of the stone, resulting in insufficient calcination; If the particle size is too small, the material layer is easy to be too thin, which will also affect the calcination effect.
Operational factors
The skill level and operation habits of operators have an important impact on the calcination effect of lime shaft kiln. Too fast feeding speed will lead to excessive material accumulation in the kiln, poor heat transfer and partial fire. Uneven distribution of materials in the kiln will also lead to uneven distribution of materials, with more materials on one side and less materials on the other, thus affecting heat transfer and distribution. Improper adjustment of air volume will also affect the calcination effect. Excessive air volume will lead to rapid fuel combustion and high local temperature; If the air volume is too small, the fuel combustion is insufficient and the heat transfer is uneven.
Equipment factor
The equipment condition of lime shaft kiln is also an important cause of partial fire. Lax sealing of the kiln body will lead to heat loss and uneven distribution of air flow in the kiln, resulting in partial fire. The abrasion or falling off of refractories will lead to uneven heat distribution in the kiln and affect the calcination effect. The blockage of the air cap will affect the air flow distribution, resulting in uneven air flow movement in the kiln, resulting in partial fire. In addition, problems such as kiln body inclination and coking in the kiln may also lead to uneven distribution of materials in the kiln, resulting in partial fire.
Fuel factor
The quality and supply of fuel also have an important impact on the calcination effect of lime shaft kiln. Poor fuel quality or insufficient combustion will lead to uneven heat transfer and partial fire. Insufficient fuel supply will also lead to insufficient combustion and affect the calcination effect. In addition, the unreasonable structure of the combustion chamber will also lead to uneven combustion and partial combustion. For example, too large or too small anthracite particles and too much or too little air volume may lead to insufficient combustion or premature combustion, thus affecting the calcination effect.
Air distribution in kiln
The air distribution in the kiln is one of the key factors affecting the calcination effect of lime shaft kiln. Uneven airflow distribution will lead to uneven heat transfer, resulting in partial fire. Unreasonable air supply system, such as improper design of air supply pipeline and uneven distribution of air caps, will affect the air distribution in the kiln. Uneven pressure distribution in the kiln will also affect the air flow movement. For example, excessive pressure on the kiln top will cause the air flow to form eddy currents near the kiln top, affecting the heat transfer. The air permeability of materials will also affect the air distribution. Materials with poor air permeability will hinder the air movement, resulting in uneven heat transfer.
The causes of partial fire in lime shaft kiln are complex and diverse, involving raw materials, operation, equipment, fuel and gas distribution in the kiln. Only by comprehensively and thoroughly analyzing these reasons and taking corresponding measures can we effectively solve the problem of partial fire in lime shaft kiln, improve the output and quality of lime, reduce energy consumption, and realize the high efficiency, stability and environmental protection of lime production.
