Analysis and Treatment Methods of Common Problems in Lime Kilns
Lime kilns often encounter various problems during operation, which not only affect production efficiency but may also lead to a decrease in product quality. Analyze the common problems of lime kilns and propose corresponding solutions, in order to provide reference for lime production enterprises.
1、 Burning problem
Raw burning refers to the incomplete decomposition of limestone during the calcination process, resulting in the production of raw lime containing undecomposed calcium carbonate. The main reasons for raw burning include excessive limestone particles, low fuel ratio or low calorific value, and unreasonable air supply.
Handling method:
Particle size control: The particle size of limestone should be controlled within a reasonable range. For ordinary vertical kilns, the particle size of limestone should be controlled between 40-80mm, and for larger kilns, it can be relaxed to 50-150mm.
Optimize fuel ratio: Ensure that the fuel calorific value meets the requirements, and control the fuel particle size reasonably to improve combustion efficiency.
Adjust air supply: Improve the air supply system to ensure sufficient and evenly distributed air volume, promoting uniform combustion of fuel.
2、 Overheating problem
Overheating refers to the excessive decomposition of limestone during the calcination process due to high temperature or prolonged time, resulting in the formation of dense burnt lime or dead burnt lime. Overburnt lime has low activity and is difficult to differentiate in subsequent production.
Handling method:
Adjust fuel ratio: Reduce fuel consumption to ensure an appropriate ratio of fuel to limestone.
Optimize air supply: Adjust the air supply volume to avoid excessive air volume causing high combustion temperature.
Strengthen ventilation inside the kiln: Ensure smooth ventilation inside the kiln, timely discharge exhaust gas, and reduce the residence time of limestone in the kiln.
3、 The issue of upward or downward movement in the calcination zone
The upward movement of the calcination zone will cause the fuel to burn prematurely in the upper part of the kiln, and when the furnace charge drops to the calcination zone, the fuel has lost its firepower, resulting in raw combustion; Moving the calcination zone downwards will cause the mixture to move faster, shorten the cooling zone, and allow air to enter the calcination zone without sufficient preheating, resulting in a decrease in the amount of calcium carbonate decomposition.
Handling method:
Adjusting the top temperature: By adjusting the combustion parameters, the kiln top temperature can be controlled to avoid excessive or insufficient top temperature.
Adjust air pressure and volume: Reduce or increase the supply air volume appropriately to keep the fire layer in a reasonable position.
Adjust the amount of stone loading and ash unloading: Reasonably control the amount of material loading and ash unloading to avoid loading too much or unloading too quickly at once.
Lime kilns often encounter problems such as raw burning, over burning, and the upward or downward movement of the calcination zone during operation. By deeply analyzing the causes of these problems and taking corresponding measures, the efficiency of lime production and product quality can be significantly improved. Meanwhile, strengthening equipment management, optimizing production processes, and improving operational skills are also key to preventing and solving these problems.
