Refractories for different parts of blast furnace lining

Refractories for different parts of blast furnace lining

The blast furnace part is divided into furnace throat, furnace body, hearth and hearth. With the large-scale blast furnace, the refractory materials used in various parts of the furnace lining have higher requirements. aspect improvement.

There are many varieties of refractory materials for blast furnace lining, and blast furnace lining is also a continuously improving technology. It has evolved from cement-bonded spray lining to silica sol-bonded lining material, although domestic manufacturers of silica sol-bonded lining materials are also There are only a few, but technological progress is unstoppable.

The throat of the blast furnace is directly impacted and rubbed by the charge, but the temperature is not very high. It can be built with dense clay bricks, high alumina bricks, clay castables, or spray paint.

The furnace body is seriously eroded by materials and high-temperature airflow, and is eroded by rising dust and carbon deposition. The middle and upper parts use dense clay bricks and high alumina bricks. Phosphorus-impregnated bricks or high-alumina bricks and sillimanite bricks are also used for masonry; the lower part of the furnace body is built with dense clay bricks, high-alumina bricks, corundum bricks, and silicon carbide bricks.

The furnace belly is seriously eroded by iron slag. In addition, due to comprehensive factors such as high temperature and erosion, refractory materials are used for serious damage, and low-porosity clay bricks, high-alumina bricks, graphite bricks, silicon carbide bricks, corundum bricks, etc. are used for masonry.

The hearth is the holding part of molten iron and slag, the temperature is about 2000℃ at the highest, and the temperature of the furnace bottom is about 1500℃. In addition to being affected by high temperature, the lining of the hearth is also subjected to erosion and erosion by slag iron. The tuyere part of the hearth is built with corundum mullite bricks and brown corundum bricks. The hot surface of the slag-iron contact is made of corundum mullite bricks and brown corundum bricks. Carbon bricks and molded carbon bricks are used for masonry, brown corundum low-cement prefabricated blocks are used for the side walls, small carbon bricks are hot-pressed in the hearth, and graphite semi-graphite carbon bricks and microporous carbon bricks are used for the bottom of the furnace. Filling the space with anhydrous pressure into the mud.

Clay bricks, silicon carbide bricks, graphite bricks, fused corundum castables, silicon carbide castables, and hot spray repairing materials for iron ditch are used for blast furnace tapping trenches, and low-cement and high-aluminum castables are used for trench covers.

The skimmer part uses low cement corundum castable, the swing nozzle is similar to the iron groove, and the slag discharge groove can use no-bake castable.