In the iconic scene of human industrial civilization, steel smelting, the blazing blast furnace, the flying converter, and the blazing heating furnace together constitute the magnificent picture of modern industry. In these extreme environments with temperatures exceeding 1600°C, refractory bricks form the lining defense line of key equipment. This industrial consumable made of inorganic non-metallic materials supports the stable operation of the entire steel production system with its excellent high temperature resistance and adaptability to complex environments. From blast furnaces to continuous casting machines, the life of refractory bricks directly affects the equipment operating rate and production costs, and its technological evolution is a key factor in promoting the development of the steel industry towards high efficiency, energy saving, and environmental protection.

1. Core functions and demand scenarios of refractory bricks

Steel production involves extreme environments such as high-temperature smelting and slag erosion. Refractory bricks must meet the following requirements:

a. High temperature resistance‌: withstand high temperatures above 1600°C (such as blast furnaces and converters).
‌
b. Corrosion resistance‌: resist chemical erosion by slag and molten metal.

c. Thermal stability‌: withstand sudden temperature changes (such as furnace opening and shutdown).

d. Mechanical strength‌: withstand furnace charge impact and equipment pressure.

Main application scenarios‌:

‌a. Blast furnace‌: furnace hearth, furnace body (commonly used clay bricks and corundum bricks).
‌
b. Converter/electric furnace‌: lining (mainly magnesia carbon bricks).

‌c. Ladle/tundish‌: lining (alumina-magnesia carbon bricks, zirconium-containing materials).

‌d. Heating furnace/soaking furnace‌: insulation layer (lightweight refractory bricks).

2. Comparison of Key Performance Indicators

Type

Refractoriness (℃)

Compressive strength (MPa)

Slag erosion resistance

Typical application scenarios

Magnesia carbon brick

>1800

30-50

★★★★★

Converter lining, ladle

High alumina brick

1750-1790

40-70

★★★★

Blast furnace body, hot blast furnace

Corundum brick

>1900

50-100

★★★★☆

High-temperature smelting furnace lining

Alumina magnesium carbon brick

1700-1750

25-40

★★★★

Ladle/tundish

Lightweight insulation brick

1300-1500

45792

★★

Heating furnace insulation layer

3. Technology development trend

Material innovation

Composite materials: Nano coating, non-oxide (SiC, Sialon) enhance corrosion resistance.

Recycling: The recycling rate of waste refractory bricks has increased to 35% (industry target for 2025).

Green energy saving

Low thermal conductivity materials: Reduce heat loss in the furnace (such as microporous refractory bricks).

Low carbon production: The proportion of chromium-free refractory materials exceeds 60% (mandatory policy requirement).

4. Selection and application suggestions

Blast furnace scene

Heater/bottom: corundum bricks (strong resistance to molten iron penetration).

Middle and upper part of the furnace: high alumina bricks (high cost performance).

Converter/electric furnace

Slag line area: magnesia carbon bricks (MgO ≥ 80%, with antioxidants added).

Steel outlet: magnesium zirconium composite materials (anti-scouring performance increased by 30%).

Maintenance optimization‌

Regular gunning maintenance to extend service life (such as hot gunning technology).
Avoid rapid cooling and heating (cooling rate during shutdown <50℃/h)

‌Conclusion‌

Refractory bricks in the steel industry are developing towards high performance, intelligence, and environmental protection. The selection needs to be combined with equipment conditions and the overall life cycle cost for comprehensive decision making.

Rongsheng Refractory produces refractory bricks and other refractory materials used in the steel industry. Welcome every customer to contact us for product details and ex-factory price.