Solid fuel burner, solid fuel burner combustion method, combustion apparatus and combustion apparatus operation method

摘要

Subject A solid fuel burner and its combustion method suited for encouraging fuel ignition and avoiding slugging caused by combustion ash, wherein a gas of low oxygen concentration (exhaust combustion gas) is used as a carrier gas of such a low grade solid fuel as brown coal. Means for Solving the Subject An additional air nozzle 12 for jetting additional air having a velocity component in the circumferential direction of a fuel nozzle 11 is provided in the fuel nozzle 11, thereby encouraging mixing between the fuel and air in the fuel nozzle 11. Further, the amount of air supplied from the additional air nozzle 12 is adjusted in response to the difference in combustion loads. Under light load, the amount of air supplied from the additional air nozzle 12 is increased so as to increase the oxygen concentration of the circulating flow 19 formed downstream of the outside of the outlet of the fuel nozzle 11, whereby stable combustion is ensured. Under heavy load, by contrast, the amount of air supplied from the additional air nozzle 12 is decreased, and a flame is formed away from the fuel nozzle 11 in such a way that burner structures and furnace wall will be less subjected to radiant heat.