The main classification of low nitrogen burners

(1) Stage burner

The stage burner designed according to the principle of graded combustion, so that the fuel and air mixed in sections, because the combustion deviates from the theoretical equivalent ratio, so it can reduce the generation of NOx.

(2) Self-recirculation burner

One is to use the pressure head of combustion air to suck back part of the combustion flue gas into the burner and mix with air for combustion. Due to the recirculation of flue gas, the heat capacity of combustion flue gas is large, the combustion temperature is reduced, and NOx is reduced.Another own recirculation burner is part of the flue gas directly in the burner into the recirculation, and join the combustion process, such burners have a dual effect of inhibiting nitrogen oxides and energy saving.

(3) Thick and light type burner

The principle is to make part of the fuel for over-dense combustion, another part of the fuel for over-light combustion, but the overall air volume remains the same. As both parts are burning in deviated chemical equivalent ratio, thus NOx are very low, this kind of combustion is also called deviated combustion or non-chemical equivalent combustion.

(4) Split flame burner

The principle is to divide a flame into several small flames, due to the small flame heat dissipation area, the flame temperature is lower, so that the "thermal reaction NO" is reduced. In addition, the small flame shortens the residence time of oxygen, nitrogen and other gases in the flame, which has an obvious inhibiting effect on "thermal reaction NO" and "fuel NO".

(5) Mixing promotion type burner

The flue gas residence time in the high temperature zone is one of the main factors affecting the amount of NOx generation. Improving the mixture of combustion and air can make the thickness of the flame surface thinner, and in the case of constant combustion load, the flue gas residence time in the flame surface, that is, the high temperature zone, is shortened, thus reducing the amount of NOx generation. Mixing promotion type burner is designed according to this principle.

(6) low NOx pre-combustion chamber burner

Pre-combustion chamber is a high-efficiency, low-NOx graded combustion technology developed in China in the past 10 years, pre-combustion chamber is generally composed of primary air (or secondary air) and fuel injection system, etc. The fuel and primary air are mixed quickly, and a fuel-rich mixture is formed in the primary combustion zone of the pre-combustion chamber, due to the lack of oxygen, only part of the fuel is burned, and the fuel precipitates volatile fraction in the primary flame zone with poor oxygen and low flame temperature, thus reducing the generation of NOx.