A study on fragmentation and emissions characteristics during combustion of injected pulverizcred coal

Abstract

In this paper, an experimental system of pulverized coal carrying flow combustion based on a flat-flame diffusion flame burner was built. The coal combustion characteristics including ignition process, coal fragmentation and surface morphology were investigated, and the CO and CO2 emission characteristics of pulverized coal during combustion, and the changing pattern of functional groups on the surface of coal char. As indicated by the experimental results, the flame front of the pulverized coal combustion fluctuates periodically, and the fluctuation frequency exerts an influence on the stability of the temperature field around the pulverized coal particles. While increasing the specific surface area of the pulverized coal, fragmentation during combustion reduces the particle size of the pulverized coal. Pulverized coal with fragmentation characteristics shows a higher combustion efficiency in blast furnace injection. The content of functional groups on the surface of coal particles has an effect on the production of CO and CO2, and the increase in the oxygen-containing functional groups on the surface of coal char promotes the generation of CO.