Economical and Efficient Protection for Blast Furnace Hearth

The accidents of blast furnace(BF) hearth were reported frequently.1,2) The burn out of hearth occurred from small BF (100 m3) to large BF (4 747 m3), hearth had always been the limiting area for long campaign life of BF.3) However, the erosion mechanism of carbon brick was not clear although many dissection investigations were carried out in the past.4,5) Raw materials containing titania charged in BF is the universal measure to prolong the service life of hearth. The injection of titania powder from tuyere and the application of taphole clay containing titania are considered as effective methods, while, the addition of ore containing titania from BF top is announced more convenient.6–9) Titania content, total iron grade, basicity and price change with the variety of ore. It is the concern for operators to choose the economical ore containing titania for protection.10–12) The effect of titania content on metallurgical properties of the ore was investigated by many papers,13,14) the evaluation of the economy only based on price was concluded to be one-sided, few people synthetically evaluate the economy of the ore containing titania based on the price, the flux amount, the iron production and the slag amount.15) In addition, the evaluation index of the protection effect is lacking, the stability of the protection effect can’t be guaranteed due to the change of operation, the time to increase titanium load becomes the key for operators.16,17) In the current study, the reasons for the erosion of carbon brick were analyzed, a model of economical and efficient protection for hearth was established based on various Economical and Efficient Protection for Blast Furnace Hearth