A:Burners and their arrangement
B:DC burner and its layout
C: Swirl burner and its arrangement
D: Stable combustion technology of mordant flame
E: Combustion Pollutant Control Methods
The combustion equipment of pulverized coal boiler furnace chamber power plant boiler mainly includes pulverized coal burner and furnace. The function of the burner is to send the fuel and the air required for combustion into the furnace gate through the nozzle in the form of jet flow according to a certain ratio, speed and mixing method, so as to ensure that the fuel is fully mixed with the air in the furnace gate, ignites in time, burns stably and burns out. . The performance of the burner has a great influence on the stability and economy of combustion.
The basic requirements for pulverized coal boiler burners are:
a. To ensure full mixing of fuel and air, timely ignition, stable combustion and burnout, and high combustion efficiency.
b. It can form a good aerodynamic field in the furnace, and the flame is well filled in the furnace, and it will not hit the wall and stick to the wall to avoid slagging.
c. Better fuel adaptability and load adjustment range
d. Can reduce the formation of NO, reduce environmental pollution
e. Simple structure, less flow resistance
The air sent to the burner is rationally organized and sent in batches according to the benefits of ignition and combustion. According to the different functions of the air sent in, the air sent in can be divided into three types:
Primary air: the air that carries pulverized coal into the burner, the main function is to transport pulverized coal and meet the oxygen demand for volatile combustion in the early stage of combustion, the amount of primary air is generally small
Secondary air: the air sent in after the pulverized coal airflow is ignited, the main function is to supplement the air needed for the continuous combustion of pulverized coal, and to organize the disturbance and mixing of the airflow in the furnace.
Tertiary air: When the pulverizing system adopts the medium-storage hot air to feed the powder, the exhausted coal grinding gas is sent to the furnace for combustion through a separate nozzle.
Classification of burners: According to the characteristics of the outlet airflow of the burner, it can be divided into two categories: direct current burner and swirl burner. Direct-flow burner: A burner whose outlet airflow is a direct-flow jet or group of direct-flow jets.
Swirl burner: The outlet airflow can be a combination of several coaxial rotating jets, or a combination of rotating jets and straight jets, but the main flow is a burner with rotating jets.
Once-through burners and their arrangement
The direct-flow burner is composed of a group of circular or rectangular nozzles, and the secondary air is sprayed into the furnace from the respective nozzles in the form of a direct jet.