Maintenance Manual for Thermal Equipment Malfunctions in Lime Kiln and Vertical Kiln
1、 Fault diagnosis and safety preparation
Fault identification:
Raw burning: Check whether the particle size of limestone exceeds the standard of 40-80mm, whether the fuel calorific value is below 5500 kcal, or whether the air supply is uneven.
Overheating: Confirm whether the combustion temperature exceeds 1200 ℃ and whether the fuel ratio is excessive.
Kiln body air leakage: Observe whether there are cracks or aging seals on the kiln roof and walls.
Tumor formation: Monitor whether the ash temperature remains consistently high and whether the concentration of CO ₂ in the kiln gas decreases abnormally.
Safety measures:
Cut off the power and gas valves before stopping the kiln, and wear protective equipment such as heat-resistant gloves and fire-resistant clothing.
Only when the temperature inside the kiln drops to a safe range (≤ 60 ℃) can one enter, ensuring good ventilation.
2、 Maintenance operation process
Kiln body sealing repair:
Clean up the debris at the cracks in the kiln body, fill and compact it with refractory mud, and apply high-temperature sealant on the outer layer.
When there is air leakage at the top of the kiln, replace the sealing strip and reinforce the kiln door hinge.
Combustion system maintenance:
Clean the carbon deposits on the burner nozzle and adjust the flame angle to form a 15 ° angle with the centerline of the kiln body.
Calibrate the fuel metering pump to ensure a proportioning error of ≤± 2%.
Tumor clearance:
After stopping the kiln, cool it naturally to 200 ℃, use a pneumatic pick to break the lumps, and use a high-pressure water gun to rinse.
Adjust the particle size of raw materials to the standard range, optimize the fabric method, and avoid local fuel accumulation.
3、 Commissioning and acceptance after maintenance
No load trial operation:
Start the induced draft fan and monitor whether the negative pressure inside the kiln is stable within the range of -50 to -80 Pa.
Check the ignition success rate of the burner. Three consecutive successful ignitions are considered qualified.
Hot state acceptance:
After production, monitor whether the kiln top temperature fluctuates between 1000-1200 ℃ and the CO ₂ concentration is ≥ 35%.
Take samples to test the activity of lime, ensuring that it is ≥ 300ml (4mol/L HCl titration method).
4、 Preventive maintenance recommendations
Daily inspection:
Check the tightness of the connecting bolts of the kiln body daily and record the fluctuation curves of parameters such as kiln temperature and pressure.
Clean the accumulated ash in the kiln once a week to prevent an increase in ventilation resistance.
Regular maintenance:
Replace the kiln body seals once every quarter and check the wear thickness of refractory bricks every six months.
During the annual overhaul, a comprehensive inspection and testing of the kiln body is carried out, and components with excessive corrosion are replaced.
