A Study of Pulverized Coal Blending Structure of Blast Furnace Injection in Ningbo Steel

Generating a reasonable coal blending scheme is of important significance for improving the effect of pulverized coal injection and reducing fuel cost. Taking five kinds of pulverized coal and mixed coal of blast furnace in Ningbo Steel as the materials, experiments of pulverize coal grindability, ignition, ash fusibility and thermal gravimetric analysis were carried out, the performances of various coal were analyzed. On this basis, the pulverized coal blending components were adjusted to determine the economic and efficient coal blending structure. Results show that coal blending should be based on bituminous coal, the ratio of low volatile anthracite should be stabilized, the proportion of volatile anthracite should be advisably adjusted. In condition of bituminous ratio more than 35% (mass fraction), the pulverized coal volatile should be controlled in the target value about mass fraction of 18%, which can not only meet the needs of safe production of coal powder injection, but also can meet the requirements of blast furnace production to the composition index of coal injection.