Effect of post-combustion air distribution on NOx original emission and combustion characteristics of 75 t/h coal slime circulating fluidized bed boiler

Coal slime has been discharged or piled up on the spot as solid waste for a long time, causing a lot of waste of resources and environmental pollution. A 75 t/h circulating fluidized bed (CFB) boiler with post-combustion technology was built for combustion of coal slime. To explore the post-combustion technology and the influences of post-combustion air speed and number of post-combustion air nozzles on combustion and original NOx emission characteristics of Yankuang Coal Slime, the experiments were carried out on a 75 t/h circulating fluidized bed industrial boiler. The experimental results showed that post-combustion technology makes the NOx original emission lower and can meet ultra-low emission requirement. Both the post-combustion air speed and the number of post-combustion air nozzles affected the post-combustion air flow. As the post-combustion air speed and the number of post-combustion air nozzles increase, NOx original emissions decreased and CO emissions increased slightly.