Combustion burner, solid-fuel-combustion burner, solid-fuel-combustion boiler, boiler, and method for operating boiler

Abstract

Provided is a combustion burner including: a fuel nozzle ( 51 ) that is able to blow a fuel gas obtained by mixing pulverized coal with primary air; a secondary air nozzle ( 52 ) that is able to blow secondary air from the outside of the fuel nozzle ( 51 ); a flame stabilizer ( 54 ) that is provided at a front end portion of the fuel nozzle ( 51 ) so as to be near the axis center; and a rectification member ( 55 ) that is provided between the inner wall surface of the fuel nozzle ( 51 ) and the flame stabilizer ( 54 ), wherein an appropriate flow of a fuel gas obtained by mixing solid fuel with air may be realized.

1 . A method for operating a boiler including a furnace that burns solid fuel and air, a heat exchanger that collects heat by a heat exchange inside the furnace, a fuel nozzle that is arranged to blow a fuel gas obtained by mixing solid fuel with primary air to the furnace, a secondary air nozzle that is arranged to blow secondary air from the outside of the fuel nozzle into the furnace, and an additional air nozzle that is arranged to blow additional air to the upside of the fuel nozzle and the secondary air nozzle in the furnace,
 wherein a distribution between a total air amount of the primary air and the secondary air and an air amount of additional air is adjusted in response to a volatile content of the solid fuel.   
     
     
         2 . The method for operating the boiler according to  claim 1 ,
 wherein the furnace is provided with a tertiary air nozzle that is arranged to blow tertiary air from the outside of the secondary air nozzle, and the control device is arranged to control the air amount adjusting device in response to the volatile content of the solid fuel so as to adjust a distribution of the total air amount of the primary air and the secondary air, and the total air amount of the tertiary air and the additional air.   
     
     
         3 . The method for operating the boiler according to  claim 2 ,
 wherein the control device is arranged to control the air amount adjusting device so that the primary air amount and the additional air amount become a predetermined air amount, and to adjust a distribution of the secondary air and the tertiary air in response to the volatile content of the solid fuel.   
     
     
         4 . The method for operating the boiler according to  claim 2 ,
 wherein the control device is arranged to control the air amount adjusting device so that the tertiary air amount and the additional air amount become a predetermined air amount while the primary air and the secondary air are fixed.   
     
     
         5 . The method for operating the boiler according to  claim 1 ,
 wherein the control device is arranged to increase a distribution of the secondary air when the volatile content of the solid fuel increases.   
     
     
         6 . The method of operating the boiler according to  claim 1 ,
 wherein the furnace is provided with a tertiary air nozzle that is arranged to blow tertiary air from the outside of the secondary air nozzle, and a distribution of the total air amount of the primary air and the secondary air, and the total air amount of the tertiary air and the additional air is adjusted in response to the volatile content of the solid fuel.   
     
     
         7 . The method for operating the boiler according to  claim 1 ,
 wherein the distribution of the secondary air is increased when the volatile content of the solid fuel is increased.   
     
     
         8 . A boiler comprising:
 a furnace for burning solid fuel and air;   a heat exchanger for collecting heat by a heat exchange inside the furnace;   a fuel nozzle that is arranged to blow a fuel gas obtained by mixing solid fuel with primary air into the furnace;   a secondary air nozzle that is arranged to blow secondary air from the outside of the fuel nozzle to the furnace;   an additional air nozzle that is arranged to blow additional air to the upside of the fuel nozzle and the secondary air nozzle in the furnace; and   an air amount adjusting device that is arranged to adjust the amount of the air supplied to the fuel nozzle, the secondary air nozzle, and the additional air nozzle, and is arranged to control the air amount adjusting device in response to a volatile content of the solid fuel,   wherein the control device controls the air amount adjusting device in response to the volatile content of the solid fuel so as to adjust a distribution of the total air amount of the primary air and the secondary air, and an air amount of the additional air.