LAUSR

Changes in the combustion system are one of the paths leading to improved combustion quality. This is manifested by a reduction of the unburnt carbon in fly ash and slag and a reduction in harmful emissions. The article presents the numerical analysis of the modification of the combustion system in the OP 650 boiler. The modifications consisted of changing the direction of swirl of the dust–air mixture in individual burners and changing the distribution of air to Over-Fire Air (OFA) nozzles. These had an impact on NOx and CO emissions and the temperature achieved at the outlet of the chamber. The content of O 2 , CO, and NOx emissions, flue gas temperature at the outlet from the chamber, flue gas temperature after the platen superheater, as well as temperature at the outlet from the model were presented. The percentage of coal flow directed towards the slag hopper was also noted.