Simulation of Efficiency and Low NOx Combustion-Supporting Technology by Local Oxygen-Enrichment in Pulverized Coal Boiler

摘要

To solve problems such as low thermal efficiency, high concentration of NOx emissions and slag bonding of a 150t/h pulverized coal boiler, A new idea of using enrichedoxygen air as the over flame air (OFA) and welted edge air was proposed. With the help of computer numerical simulation technology and using k-e-g turbulence combustion model for computations of the gas phase and two competing reactions for the coal devolatilization, the velocity and temperature field and concentration of NOx in the combustion of pulverized coal were simulated. The simulation result shows that the local oxygen-enrichment combustion-supporting technology used in tangential pulverized coal boiler can improve the dynamic field characteristics and combustion stability in the furnace effectively, and has a very positive role on reducing the concentration of NOx emissions.