Physical and mathematical modeling of solid fuel combustion in the application of direct-flow burners

Abstract

The tightening of standards for emissions of harmful substances into the air makes it increasingly important to pay attention to fuel combustion technology. The concentration of nitrogen oxides in flue gases on solid fuel boilers, in most cases, exceeds the standard value. The most significant excess in NOx emissions occurs in boilers wit slag-tap removal. The possibility of influence on the aerodynamics of the furnace when using vortex burners, which are individual action burners, on powerful boilers is severely limited. When direct-flow burners, which are collective action burners, there is a possibility of significant impact on the aerodynamics of the active combustion zone. With a rational arrangement of direct-flow burners and nozzles and the use of step combustion, it is possible to provide a significant reduction in the formation of nitrogen oxides, mechanical underburning of solid fuel particles and to prevent the possibility of slag of the screen system. The main problem of using direct-flow burners is the need to study the aerodynamics of each specific combustion volume of different boilers. On the basis of research on physical and mathematical models developed schemes of solid fuel combustion in steam boilers using direct-flow burners and nozzles in the presence of a large number of horizontal and vertical vortices, which should contribute to the efficient combustion of fuel with low emissions of nitrogen oxides.