Combustion plant and method for operating a combustion plant

Abstract

A special distribution of nozzles in the flue gas outlet and their alignment make it possible to guide the flue gas along a wavy line. The addition of combustion air for primary air and secondary air can be variably distributed during operation of the combustion plant, for example so as to also keep the burnout per unit of time constant while maintaining a constant combustion air ratio.

What is claimed is: 
     
         1 . A combustion plant with a flue gas outlet, which has nozzles on opposing sides of the flue gas outlet, so as to inject a fluid into the flue gas, wherein the nozzles are arranged and aligned in such a way as to move the flue gas in the flue gas outlet back and forth along a wavy line. 
     
     
         2 . The combustion plant according to  claim 1 , wherein the fluid is a gas. 
     
     
         3 . The combustion plant according to  claim 2 , wherein the gas is air. 
     
     
         4 . The combustion plant according to  claim 2 , wherein the gas is steam. 
     
     
         5 . The combustion plant according to  claim 1 , wherein the wavy line has three, and preferably more than four reversal points. 
     
     
         6 . The combustion plant according to  claim 1 , wherein the primary nozzle direction of the two nozzles arranged on opposing sides of the flue gas outlet lies at an angle of at least 5°, preferably of more than 10°, from a line connecting the nozzles. 
     
     
         7 . The combustion plant according to  claim 1 , wherein the primary nozzle direction of a nozzle deviates from the shortest connection to the opposing side of the flue gas outlet by an angle of at least 5°, preferably of more than 10°. 
     
     
         8 . The combustion plant according to  claim 1 , wherein the primary nozzle direction of at least one nozzle deviates from a horizontal plane in the flue gas outlet by an angle of at least 5°, preferably of more than 10°. 
     
     
         9 . The combustion plant according to  claim 1 , wherein the combustion plant has a furnace grate for combustion. 
     
     
         10 . The combustion plant according to  claim 9 , wherein the flue gas outlet of the furnace grate expands in the direction of flow of the flue gas. 
     
     
         11 . The combustion plant according to  claim 9 , wherein the flue gas outlet has a lower area and an upper area, wherein the access from the furnace grate to the flue gas outlet in the lower area is arranged offset to the upper area. 
     
     
         12 . The combustion plant according to  claim 9 , wherein at least one nozzle is arranged above the furnace grate in the direction of flow of the flue gas before the flue gas outlet, so as to inject fluid into the flue gas. 
     
     
         13 . A method for operating a combustion plant according to  claim 1 , in which at least a portion of the combustion air is added to the flue gas through nozzles arranged on opposing sides of the flue gas outlet, wherein the combustion air is added as primary combustion air and secondary combustion air or as secondary combustion air during operation of the combustion plant at several varyingly different addition points. 
     
     
         14 . The method according to  claim 13 , wherein the combustion air ratio is held constant. 
     
     
         15 . The method according to  claim 13 , wherein the combustion air is added distributed to the nozzles and grate. 
     
     
         16 . The method according to  claim 13 , wherein the distribution of partial volume flows to these nozzles is controllably varied. 
     
     
         17 . The method according to  claim 13 , wherein, during operation of the combustion plant, the combustion air is distributed to the individual addition points optimized for NO x , CO and/or O 2 . 
     
     
         18 . The method according to  claim 13 , wherein the distribution of combustion air is split among the nozzles in the flue gas outlet in such a way as to achieve a nearly constant burnout (gas and/or solid burnout) per unit time.