01, frontier overview
Blast furnace is a large high-temperature metallurgical furnace using coke reduced iron ore to smelt hot metal. The temperature, pressure, nature of physical and chemical changes, and harshness of working conditions of the lining at different heights in the blast furnace are different, so the mechanism and condition of the lining damage are also different, and the selection of refractory materials is naturally different.
02, furnace throat
Furnace throat is the throat of blast furnace, which is easily damaged by the impact and friction of falling solid charge. Generally, high hardness and high density aluminum brick masonry is used, and wear-resistant cast steel protective plate is used.
03, furnace body
The furnace is the middle part of the furnace throat to the furnace waist, divided into upper, middle and lower three belts, the upper and middle of the furnace lining is mainly subjected to the wear and erosion of the falling charge and the rising dust bearing air flow, the degree of damage is relatively light, generally using free Fe2O3 special clay bricks, or dense clay bricks, or high aluminum brick masonry, can also be composed of clay amorphous refractory materials.
The furnace body temperature is high, there are a lot of slag formation, slag and lining surface direct contact, lining damage faster, generally choose good fire resistance, slag resistance, high temperature structural strength and good wear resistance of high-quality dense clay brick or high aluminum brick masonry. High aluminum brick, corundum brick, carbon brick or silicon carbide brick are mainly used in the lower part of the large blast furnace body.
04, furnace waist
The furnace waist is the broadest part of the blast furnace, the chemical erosion of slag, the erosion of alkali metal vapor, and the friction and erosion of falling charge and high temperature coke on the lining surface are very serious, and become one of the most vulnerable parts of the blast furnace. Medium and small blast furnace can use high quality dense clay brick or high aluminum brick, corundum brick; Large modern blast furnaces generally use high aluminum brick, corundum brick or silicon carbide brick, and also use carbon brick masonry.