The low nitrogen burner is used as a common type of burner in industry, and it is divided into six kinds according to the different use principle of low nitrogen burner to facilitate the use of customers.
In the 1. stage low nitrogen burner, a stage burner designed according to the principle of graded combustion is designed to mix fuel and air in a piecewise mixture. Because of the deviation of the theoretical equivalent ratio of combustion, the generation of NOx can be reduced.
2. Self-recirculating low-nitrogen burner is a kind of burner which uses the pressure head of combustion-supporting air to suck part of the burning flue gas back into the burner and mix it with air. Because of the flue gas recirculation, the heat capacity of the combustion flue gas is large, the combustion temperature is reduced, and the NOx decreases. Another kind of self recirculating burner is to recirculate part of the flue gas directly in the burner and add the combustion process. This kind of burner has the double effect of reducing nitrogen oxide and energy saving.
3. The principle of the dense-lean low-nitrogen burner is to make some of the fuels burn excessively dense and some of the fuels burn excessively light, but the overall air volume remains unchanged. Because both parts are burned at a deviation from the chemical equivalence ratio, NOx is very low. This combustion is also called deviation combustion or non-chemical equivalence combustion.
The principle of the 4. division flame type low nitrogen burner is to divide a flame into several small flames. Because of the large heat dissipation area and low flame temperature, the "thermal reaction NO" is reduced. In addition, small flame shortens the residence time of oxygen, nitrogen and other gases in the flame, and inhibits the "thermal reaction NO" and "fuel NO" obviously.