Method for injecting a substance into a boiler of a garbage incineration plant

Abstract

A method is provided for injecting a substance into a boiler of a garbage incineration plant using a gaseous propellant, the substance being conducted, starting from at least one distributor, via lines which branch off from the distributor, in each case to a nozzle which is assigned to the respective line and by means of which the substance and the propellant are injected into the boiler. The substance quantity to be conducted to the respective nozzle is set in the distributor. The substance and the propellant are combined upstream of the branch-off with the respective line.

1 . A method for injecting a substance into a boiler ( 4 ) of a garbage incineration plant, using a gaseous propellant, the substance being conducted, starting from at least one distributor ( 8 ), via lines ( 14   a - i ) which branch off from the distributor ( 8 ), in each case to a nozzle ( 16   a - i ) which is assigned to the respective line ( 14   a - i ) and by means of which the substance and the propellant are injected into the boiler ( 4 ), and the substance quantity to be conducted to the respective nozzle ( 16   a - i ) being set in the distributor ( 8 ), wherein the substance and the propellant are combined upstream of the branch-off with the respective line ( 14   a - i ). 
   
   
       2 . The method as claimed in  claim 1 , wherein, in the event of a change in the setting of the substance quantity to be conducted to the respective nozzle ( 16   a - i ), this change is carried out infinitely variably. 
   
   
       3 . The method as claimed in  claim 1 , wherein the substance is a reducing agent for the reduction of nitrogen oxides, in particular ammonia or urea. 
   
   
       4 . The method as claimed in  claim 3 , wherein the overall quantity of reducing agent to be injected is regulated as a function of the nitrogen oxide content, present downstream of the boiler ( 4 ), in the smoke gas. 
   
   
       5 . The method as claimed in  claim 3 , wherein the quantity of reducing agent to be conducted to the respective nozzle ( 16   a - i ) is regulated as a function of the temperature profile in the boiler ( 4 ). 
   
   
       6 . The method as claimed in  claim 5 , wherein the temperature profile in the boiler is determined by means of at least two temperature measuring apparatuses ( 18   a, b ). 
   
   
       7 . The method as claimed in  claim 6 , wherein the temperature measuring apparatuses ( 18   a, b ) used are radiation pyrometers. 
   
   
       8 . The method as claimed in  claim 1 , wherein the propellant used is air or steam. 
   
   
       9 . An apparatus for carrying out the method as claimed in  claim 1 , comprising at least one distributor ( 8 ), from which lines ( 14   a - i ) branch off which lead in each case to a nozzle ( 16   a - i ) for injecting the substance and the propellant into the boiler ( 4 ), the distributor ( 8 ) being assigned means for setting the substance quantity to be conducted to the respective nozzle ( 16   a - i ), wherein the apparatus comprises means for combining the substance and the propellant upstream of the branch-off of the respective line ( 14   a - i ) from the distributor ( 8 ).