What refractory materials are adopted in each part of the blast furnace?
The furnace throat is a part of the direct impact and friction when the burden drops, and the high density and high alumina brick is usually adopted. The upper and middle shaft temperature is only 400~800 degrees, the parts with high alumina brick and sillimanite brick.
The lower part of the shaft due to high temperature and dust by scouring and alkali metal vapor erosion, so the requirements for the slag resistance, alkali resistance and high temperature resistance, wear resistance of high quality clay brick, high alumina brick, carborundum brick or corundum brick. Belly temperature reaches 1400~1600, and slag, steam erosion, erosion and corrosion is strong, therefore, the silicon carbide reaction bonded silicon carbide brick.
Bosh temperature reaches 1600~1650, high alumina brick, corundum brick or silicon carbide brick. The upper hearth tuyere zone near the temperature at 1700~2000 Deg. C, the use of sillimanite brick, corundum and silicon carbide refractory filler, Shi Mozhi. Bottom temperature at 1450~1500 Deg. C, the use of graphite bricks and microporous carbon brick, now also used corundum brick, Gang Yumo brick and synthetic mullite brick.
