The Differentiation Stages of Fuel Oil Combustion in Fuel Oil Boilers
The Differentiation Stages of Fuel Oil Combustion in Fuel Oil Boilers
The process of fuel combustion in fuel oil boilers undergoes a series of stages, which can be differentiated into four distinct phases. The fuel oil is atomized into small droplets through an oil atomization device and then mixed with air before being injected into the furnace for suspension combustion.
1. Atomization Stage:
In the fuel atomization stage of a fuel oil boiler, the fuel oil passes through an oil atomizer and is sprayed into the furnace along with air, initially forming turbulent diffusion, turning the oil into a fine mist. This stage is necessary because the evaporation and vaporization temperature of fuel oil is much lower than its ignition temperature. In practice, the fuel oil evaporates and vaporizes before igniting.
2. Oil Droplet Evaporation and Chemical Reaction Stage:
The fuel oil in a fuel oil boiler consists of various types of hydrocarbons. Uniformly distributed oil mist absorbs heat under the high temperature within the furnace, first evaporating into gases and then thermally decomposing into low-molecular-weight hydrocarbons at temperatures between 500~600℃, which are more prone to ignition.
3. Fuel Oil and Air Mixing Stage:
After the oil mist thermally decomposes into hydrocarbon gases, it mixes with the air within the furnace to form a combustible gas mixture. Therefore, it is essential to select appropriate air distribution devices and suitable air flow rates to ensure strong and timely mixing for complete combustion.
4. Fuel Consumption Stage:
The combustion chamber of a fuel oil boiler employs a full corrugated furnace structure, which intensifies the disturbance of flue gas, increases the radiant heat transfer area, enhances the stiffness of the furnace hearth, effectively reduces the expansion stress on the furnace hearth, strengthens heat transfer effects, and promotes fuel combustion within the furnace.