email info@boilermanufactory.com


A flue gas external circulation and an internal circulation are arranged to mix the lower temperature flue gas extracted before the air preheater with the air supplied for combustion and feed it into the furnace through the burner without participating in combustion. The flame temperature can be lowered to reduce the combustion temperature and the oxygen concentration, so as to reduce the NO_x content.


  1. Through the external and internal circulation of flue gas, 10-30% of flue gas is extracted from the tail before the air preheater and mixed with the air supplied with the gas. The flue gas is sent into the furnace through the burner. The combustion temperature and oxygen concentration can be reduced by controlling the flame temperature, thus greatly reducing the emission of harmful substances such as NO_x. NO_x is less than 30mg/Nm_, which is in line with the national first-tier city exhaust. Put the standard.
  2. The tail gas of boiler contains quantitative saturated steam and turns cold water into condensed water. Therefore, the boiler uses stainless steel pipes, set up drainage pipes, effectively prevent the damage caused by corrosion to the boiler, prolong the service life of the boiler.
  3. It is designed with built-in pipeline, bi-directional support of front and back end, standard flange interface, convenient for users to install and use on site.
  4. The diameter of the furnace is large enough to ensure adequate return space for flue gas recirculation. The furnace volumetric heat load is controlled within a reasonable range, which is suitable for the demand of multi class combustion mode.
  5. Smoke pipes are densely arranged to solve the problem of flue gas velocity after the increase of flue gas volume caused by flue gas recirculation.

Related boilers


Please feel free to leave any message that you want to know!