The effects of particle grinding on the burnout and surface chemistry of coals in a drop tube furnace

摘要

Grinding coals to a pulverised coal specification for blast furnace injection can be costly, which is why some iron manufacturers choose a larger granulated coal size specification. However, there is a concern that these coals may have lower burnout in the raceway region so there is a technical and economic balance with coal grinding. This paper investigates how the process of grinding alters the physical properties, plus the surface chemistry, of coals and their chars formed in a drop tube furnace; it was found that in many cases the larger particle size coals gave improved combustion burnout compared to smaller sizes.