COMPUTERIZED ANALYSIS OF LOW-NOX COAL-FIRED UTILITY BOILERS

Mathematical modelling and simulation can be used to assess the effect of modifications of the combustion process and pollutant formation. I n this paper two pulverized coal combustion plants are considered. The first plant is a bituminous coal-fired furnace with eight swirl burne rs and a thermal power of 490 MW. In order to reduce NOx-formation, th e furnace system was modified using a different burner design and a mo dified burnout air arrangement for realizing the staging of combustion air. Both cases were investigated. The second plant is a brown coal-f ired furnace with an electric power of 150 MW. The goal was to reduce GO-emissions and to improve the burnout of the coal. For a more flexib le discretization of the domain a method was developed which allows th at each burner can be discretized by an independent grid system. Using this method, details of the burner geometry can be considered and the governing processes of pollutant formation in the near-burner zone ma y be described in more detail.