Excessive fuel composition resulting in incomplete combustion of the fuel, making GAH heat accumulating combustibles.
Boilers to purchase residual oil, cracked residual oil and leftover C4 fuel is more, their heavier components, high viscosity, low self-ignition point, easy to analyze when burning carbon, steam atomization of the fuel when the crushing capacity is also poor, large Molecular oil content is high, oil nozzle nozzle is easy to plug, so often affect the fuel atomization quality and combustion effect. Run-time if the improper adjustment of combustion, air flow inadequate or with the wind unreasonable and fluctuations in process conditions, it will have time to complete the combustion of carbon black and black smoke. The incomplete combustion of oil particles in the furnace is carried by the flue gas to the GAH heat exchange surface at the rear of the boiler. According to empirical analysis, this incident is basically a large amount of black smoke generated when the fuel is burned poorly, causing the black smoke to enter or cover the monitor probe and cause false signals to stop the vehicle.
In addition, frequent start and stop in the boiler process, due to poor combustion furnace grate, the fuel is not flammable, low flue gas flow rate, can easily lead to a large number of unburned fuel deposition; boiler low load running time is too long , Unstable combustion, low smoke speed, unburned combustible material easily deposited on the corrugated board; lessons learned from past accidents and experience also confirmed: air preheater rot rotor blocking ash, air leakage after wear, excess air flue tail or Oxygen content is too low and so can lead to fuel due to lack of oxygen and incomplete combustion. After 1997, the boiler can not work at full capacity for a variety of reasons and the flue gas flow rate is low. Sometimes, to increase the thermal efficiency of the boiler, blindly reduce the amount of surplus air in the tail. These are the air preheater secondary burned left hidden danger.