Abstract: Based on the material balance and zinc balance calculation， through the analysis of zinc behaviors in lower part of blast furnace， a calculation model for zinc solution behaviors among the slag and the hot metal was established.Zn index at BF bosh was proposed to represent the degree of circulating enrichment of zinc. The practical data of a steelwork was used for calculation， and the index of the zinc content of the coal gas in bosh of the blast furnace was 568. Zinc was in the saturation state in both slags and hot metals in the furnace， and the content of it was 316 times and 10 times as much as that in the final room temperature condition for the slag and hot metal respectively. The accumulation mechanism in blast furnace bottom brick and the erosion mechanism of zinc on tuyere were also analyzed， offering references for alleviating destructive effects of zinc on the blast furnace.

Key words: zinc, blast furnace, Zn index at BF bosh, hearth, tuyere, erosion mechanism