Blast furnace is a thermal equipment for continuous ironmaking under high temperature and reducing atmosphere, which is divided into throat, shaft, belly, bosh, hearth and bottom from above to below. Hitech Material provides a turnkey solution for blast furnace with prime refractories suitable for every part.
Blast furnace is a thermal equipment for continuous ironmaking under high temperature and reducing atmosphere, which is divided into throat, shaft, belly, bosh, hearth and bottom from above to below.
Hitech Material provides a turnkey solution for blast furnace with prime refractories suitable for every part.
Throat is where the part is affected by direct impact and friction when burden is descending. While using high dense high alumina bricks, the wear plates are used as the protection.
The upper and middle part of shaft where the temperature is just 400～800℃ mainly suffer from furnace burden impact, wear caused by rising furnace dust, gas invasion and deposit of carbon, so fireclay bricks can be used in the area. As the development of long campaign life technologies of blast furnace, high alumina bricks and sillimanite bricks are also widely applied for.
Because it has a high working temperature and a large amount of slag formed, refractories used in the lower part of shaft should have the properties of high slag resistance, good alkali resistance and good high-temperature strength, such as fireclay bricks, high alumina bricks, silicon carbide brick and corundum bricks, etc.
A large amount of slag will be formed when the temperature of belly increased up to 1400～1600℃, At the same time, this part faces erosion and friction. Because of above, refractory linings are also suffered damage.
Small-middle blast furnace: fireclay bricks, high alumina bricks, alumina carbon bricks;
Large blast furnace: silicate nitride bonded silicon carbide bricks, reaction bonded silicon carbide bricks.
Temperature reaches 1600～1650℃, and the viscosity of the slag dropped further, which is further aggravated by the damage of refractory linings. Generally, silicon carbide bricks are used in this part.
5. Hearth and Bottom
Temperature of the hearth's upper part which is near the tuyere ranges at 1700～2000℃, and furnace bottom's temperature commonly worked under 1450～1500℃, so refractories used in the two parts are influenced by melting erosion.
Hearth: sillimanite bricks, corundum castables, graphite filler, silicon-carbide refractory materials;
Taphole: Al₂O₃-SiC-C bricks, carbon blocks;
Bottom: graphite-clay bricks, micro-pore carbon bricks;
Tuyere: fireclay bricks, sillimanite bricks.