A METHOD FOR ENSURING CONNECTIVITY OF TUYERES AND TAPHOLE IN A BLOWN DOWN BLAST FURNACE BY FREEING BLOCKED VOIDAGES IN THE HEARTH.

摘要

ABSTRACT TILTLE: A METHOD FOR ENSURING CONNECTIVITY OF TUYERES AND TAPHOLE IN A BLOWN DOWN BLAST FURNACE BY FREEING BLOCKED VOIDAGES IN THE HEARTH. The present invention relates to a method for ensuring connectivity of tuyeres and taphole in a blown down blast furnace by freeing blocked voidages in the hearth. More particularly, the method ensures that there is enough voidage for the initial melt to trickle down towards tap hole when the furnace restarts. After ensuring the dead man voidage is good, the coke present near the taphole and the tuyere zone inside the hearth is heated to free the interstitial congestion between coke particles by lancing through taphole. Then selectively filling up the hearth for desired block free voidage for the initial melt and lowered viscosity of the slag formed upto the tuyere level, with large size +80 -100 mm coke blank mixed with fluorspar, DRI and fluxed coke crushed graphite/carbon electrodes (CRE), and lean burden comprising lean ore with variable coke rate.