The types and performance requirements of refractories used are as follows:
1, clay brick. The raw materials for making clay bricks are rich, which can be easily obtained from refractory soil with good plasticity and binding force, and the manufacturing process is relatively simple, so clay bricks are widely used in metallurgy.
From the performance index of clay brick, it can be seen that its main performance characteristics in the use process are strong acid slag resistance, good thermal shock resistance, good thermal insulation and certain thermal insulation performance. In ferroalloy production, the annual clay brick is mainly used to build the lining of the exposed part of submerged arc furnace, the lining of the outer layer of furnace wall and bottom, or the lining of ladle.
2. carbon bricks. The main raw materials for making carbon bricks are broken coke and anthracite, and the binder is coal tar or asphalt. It can be seen from the performance index of carbon brick that compared with other common refractories, carbon brick not only has high compressive strength, small linear expansion coefficient, good wear resistance, high refractoriness and load softening temperature, good thermal shock resistance, but also has excellent slag resistance.
In ferroalloy production, carbon brick can be used as furnace lining material for smelting ferroalloy that is not afraid of carburization. Carbon brick is easy to be oxidized at this temperature, so it is mainly used to build the furnace wall, hearth and taphole below the tuyere of submerged arc furnace, which is not in contact with air. Because of the high conductivity of carbon brick, it is easy to lift electricity by using carbon brick lining, which can appropriately reduce the height of carbon brick in furnace wall and the thickness of carbon brick in furnace bottom.
3. High alumina brick. The main raw material for manufacturing high alumina bricks is high alumina bauxite, and the binder is refractory clay. From the performance data of high alumina brick, it can be seen that its biggest advantages are high fire resistance, high load softening temperature, good slag resistance and high mechanical strength, and these properties are rapidly improved with the increase of Al2O3 content.
In ferroalloy production, high alumina brick can be used to build taphole lining brick, blast furnace shaft and submerged arc furnace hearth, and can also be used to build ladle lining.
4. Magnesium bricks and magnesium oxide. The main raw material for manufacturing magnesia brick is magnesite, and the binder is water and brine or sulfite pulp waste liquid.
From the performance data of magnesium brick, it can be seen that its main performance characteristics in the use process are high fire resistance temperature and excellent alkali slag resistance.