What are the Functions of Pulverized Coal Burners?
What are the Functions of Pulverized Coal Burners?
Pulverized coal burner is the main equipment of coal-fired boiler combustion. The main functions are:
(1) Send fuel and air to the boiler furnace;
(2) Arrange fully mixed fuel and air in time;
(3) After the fuel enters the furnace, it shall be burned stably and quickly.
In order to reduce the heat required by the pulverized coal burner and quickly heat it to the ignition temperature, the air volume required for pulverized coal combustion is usually divided into primary air and secondary air. The role of the wind is to send pulverized coal into the furnace and let it release the oxygen required for the combustion of volatiles. After the pulverized coal airflow is ignited, secondary weathering is carried out to burn the coke and residual volatile matter in the pulverized coal to make it burn.
Pulverized coal burner usually consists of rectangular or circular nozzles. Coal and hot air are ejected from the nozzle to form a DC nozzle. The DC jet velocity decays slowly, the jet center is relatively stable, and the strong mixing of the secondary air in the later stage is its main feature.
The working principle of the pulverized coal burner is that the pulverized coal moves in the air stream and is sprayed outward from the fuel pipe according to a certain diffusion angle, and a considerable amount of momentum and moment of momentum is transmitted by the combustion air in the outer vicinity; The middle part is added with swirling air to further strengthen the mixing of coal and air (including the secondary air around), and the length and thickness of the flame can be adjusted as required to obtain the required flame shape; The role of the central wind is to promote the combustion of a small amount of fuel and CO in the central part, make the combustion more sufficient, and play the role of stable flow, forming a stable combustion flame.