What are the characteristics of firebricks for hot blast furnaces and firebricks for each part:

Hot blast furnace is one of the important auxiliary equipment of blast furnace, the general requirement of hot blast furnace is: to achieve high wind, mild and long life

The parts of refractory materials used in hot blast furnaces include large wall, vault, regenerator, partition wall, combustion chamber and ceramic burner. Can be divided into high temperature area and low temperature area, the working environment of these parts:

1. The lining and lattice bricks of hot blast furnaces are often affected by sudden cooling and sudden heat changes

2, by alkali metal erosion

3. The hot blast stove itself is subjected to load

High temperature area:

1200-1350°C high temperature action; The role of sharp changes in temperature during heat exchange; Chemical erosion of dust brought by blast furnace gas

Scour effect of combustion gas; Mechanical load action, etc

Therefore, the overall requirements for the selection of refractory materials are: good creep resistance, good high temperature volume stability, high load softening temperature, and good corrosion resistance refractory materials

Medium and low temperature areas:

The selected refractory materials have large heat capacity, good hot air conductivity, low permeability, high density, high strength and good thermal shock stability

When the hot air temperature is lower than 900°C, the general selection of clay brick masonry, some of the service life of up to 20 years, when the wind temperature is higher than 900°C, high temperature parts of the furnace lining and lattice bricks are made of high aluminum brick, mullite brick, sillimanite brick and silicon brick. Of course, there are also economic factors such as the price of materials to consider

Different refractories are used in blast furnace hot blast furnaces in various factories, but there is one thing in common, and attention must be paid to the selection of refractories:

1, the resistance to high temperature load creep performance of refractory materials 2, the volume stability and thermal expansion performance of refractory materials 3, the heat exchange efficiency of hot blast stove

The firebricks used in each part of the hot blast stove are as follows

High temperature on the upper part of the big wall: silica brick, mullite brick; Middle and lower parts: high aluminum brick, sillimanite brick and clay brick

Vault area over 1400°C: using silicon, mullite, sillimanite, andalusite or low creep high alumina bricks

Heat storage upper part: silicon lattice brick; Middle: low creep high aluminum brick, mullite brick, sillimanite, andalusite brick; Lower part: Clay brick

Partition wall: The same refractory material used in the combustion chamber

Combustion chamber: high temperature area: silicon brick, mullite brick, low creep high aluminum brick, low temperature area: high aluminum brick and clay brick

Burner: Ceramic burner, mullite