The refractory brick lining should correspond to the heat flow intensity of this part, so as to maintain the integrity and stability of the brick lining under the impact of strong heat flow.

Refractory brick lining of various parts of iron-making blast furnace:

(1) Furnace throat. It mainly bears the impact and wear of the incoming charge, and generally chooses steel bricks or water-cooled steel bricks.

(2) The upper part of the furnace body. This part is an area where carbon deposition and anti-government 2CO2-CO+C are prone to occur, and the erosion of alkali metals and zinc vapor also occurs in this area, coupled with the erosion and wear of the descending charge and rising gas flow, so chemical resistance should be selected. Refractory materials with good erosion and wear resistance are suitable for high-density clay bricks, high-density third-grade high-alumina bricks or phosphoric acid-impregnated clay bricks. When the thin-walled structure is used in modern large blast furnaces, the brick lining is often replaced by the 1-3 section anti-buckling cooling stave.

(3) Take the lower part and the waist of the furnace body. The main mechanisms of damage are thermal shock spalling, high temperature gas scouring, the action of alkali metals, zinc and carbon precipitation, and chemical erosion of primary slag. The brick lining should be made of refractory materials that resist thermal shock, primary slag erosion and scour. At present, large-scale blast furnaces at home and abroad choose silicon carbide bricks with good performance but expensive (silicon nitride bonding, self-bonding, Sialon bonding>, so that the service life can reach 8 years. Practice has proved that no matter how good the refractory material is, it will be eroded. , it can be stabilized when it reaches equilibrium (about half of the original thickness), and this time is about 3 years. In fact, the use of fired aluminum carbon bricks with good performance (the price is much cheaper) can also achieve this goal. So Aluminium carbon bricks can be used for blast furnaces of 1000m3 and below.

(4) Hearth. The main reason for the damage is the erosion of high temperature gas and slag iron. The heat flow in this part is very strong, and any refractory material cannot resist it for a long time.

In production, it mainly relies on slag skin, so this part does not need to use too expensive refractory materials. The service life of the refractory material in this part is not long (1 to 2 months for long, 2 to 3 weeks for short), and refractory materials with high refractoriness, high softening temperature under load and high bulk density are generally used, such as high alumina bricks, aluminum carbon bricks Wait.

(5) Hearth tuyere area. This part is suitable for the only oxidation reaction area in the blast furnace. The high temperature generated can reach 1900-2400 ° C. The brick lining is damaged by thermal stress caused by high temperature, and the high temperature gas erosion, slag iron erosion, alkali metal erosion, circulating coke damage. Erosion, etc. Modern blast furnaces use combined bricks to build the hearth tuyere area, which is made of high alumina, corundum mullite, brown corundum and silicon carbide combined with silicon nitride, etc., and hot-pressed carbon blocks are also used.

The refractory brick manufacturer Henan Hongtai Refractories explained the lining of the refractory bricks in various parts of the iron-making blast furnace. The company is located in Xinmi. Aluminum bricks, secondary high alumina bricks, tertiary high alumina bricks, etc.