Background technology:
In recent years, China's rapid economic growth and significant increase in energy consumption have led to increasingly serious environmental pollution.At present, China's environmental protection departments on the emission of combustion pollutants emission restrictions are increasingly high.Therefore, reducing N0 emission is one of the main goals of gas burner design.
At present, the main technical means to control NO emission from gas burners include air classification, air eddy current and direct current air coordination, gas classification and flue gas re-circulation.Air classification and gas classification are limited by the installation size of existing burners, gas pressure and air pressure, NO emission reduction contribution is limited.Therefore, flue gas re-circulation has been widely used in gas boilers.The traditional flue gas re-circulation is to open the hole after the induced draft fan of the boiler, set up the circulating fan, extract the flue gas from the combustion and mix with the air, and then feed it into the burner.The mixture of circulating smoke and air dilutes the oxygen concentration while increasing the volume of cold air without increasing the oxygen concentration.Therefore, it is beneficial to reduce the flame temperature, prolong the combustion reaction time, avoid local high temperature in the furnace, and effectively inhibit the formation of NO.
The low NOx burner structure disclosed in Chinese patent literature (application 201610750727) includes internal natural gas channel, gas auxiliary channel, radial distribution device, gas injection hole, distribution pipe, swirl blade, internal gas ASI.St channel, intermediate gas auxiliary channel, external gas auxiliary channel and internal gas auxiliary channel.Layer air current limiting hole, inner vortex device and jet straight hole.However, low NOx burners have complex structures and low combustion efficiency.
Technical implementation elements:
The purpose of the invention is to provide a low nitrogen burner with simple structure, high combustion efficiency and low NOx emission in view of the above problems existing in the existing technology.
The purpose of the invention can be realized through the following technical scheme: a low-nitrogen burner, including an axial straight combustion cylinder, a gas pipe fixed in the combustion cylinder, an air pipe fixed in the gas pipe, an air pipe isolated from the gas pipe cavity, and a lower part.The end of an air and gas pipe.The lower end of the combustion tube is connected, which is characterized by the fixed connection between the upper end of the gas pipe and the combustion plate. The combustion plate is provided with through-flow holes, and the combustion plate is fixed with multiple nozzles arranged horizontally.The inner end of the nozzle is connected with the gas pipe and connects the gas pipe.The outer end is connected with the combustion cylinder, and the inner end of the lower end of the gas pipeline is provided with an impeller, which includes a plurality of slanted blades.
The lower end of the low nitrogen burner is connected to the fan.In the process of operation, air is blown into the combustion cylinder by the blower, and the air is guided to spiral rise by the impeller.Some air enters the air tube to the upper end of the combustion chamber of the combustion cylinder, thereby increasing the intake of air at the upper end of the combustion cylinder.Through the spiral rise of air in the combustion cylinder, the gas at the outer end of the nozzle tube is fully mixed, and the combustion efficiency is high.Meanwhile, the air flowing from the air tube reduces the temperature of the combustion cylinder, avoids the high temperature point at the upper end of the combustion cylinder, improves the combustion efficiency, and reduces the nitrogen oxide emissions.The burner has the advantage of simple structure.
In the low-nitrogen burner, the combustion cylinder comprises a cylindrical body and a coaxial diffusion cylinder fixed at the upper end of the body.The combustion plate and jet tube are located in the diffusion cylinder.The upper end of the diffusion tube is provided with an inward inclined flow guide surface, and the combustion plate is located on the flow guide surface.Down the side.The upper end of the diffuser has an inward-sloping guide surface, which guides the gas and air into it to achieve secondary combustion and improve combustion efficiency.
In the low nitrogen burner, an adjustment mechanism is set between the diffuser and the main body to adjust the axial distance between the diffuser and the main body.The regulating mechanism includes a strip hole.
