Characteristics and application of low-cement concretes

Low cement concrete (LCC) is a high-performance refractory material whose performance characteristics are improved by significantly reducing the cement content (typically 1/4-1/8 of the cement content of traditional refractory concretes) and adding ultra-dispersed powder (e.g. silica powder, alumina) and a high-performance dispersant. It is widely used in high temperature industries such as steel, non-ferrous metallurgy, cement and chemical industries.

Characteristics of low-cement concrete

1. higher volumetric density and strength

Low cement content (CaO content is typically 1.0-2.5%), which reduces the amount of fusible products formed and provides good volumetric stability after firing.

Bending and compressive strength in hot condition is 1.5-3 times higher than conventional concrete.

2. excellent heat resistance

The structure remains dense at high temperatures and can maintain a long service life under conditions of severe slag erosion and corrosion.

The refractory temperature can reach over 1600-1800 °C.

3. low porosity and good slag resistance

After the addition of ultrafine powder, the particle size distribution of concrete is optimized: the number of pores is reduced, the density of the structure is increased and resistance to slag erosion is increased.

4. good construction characteristics

Small amount of water added (usually 5-7%), good flowability, easy to mold and remove from the mold.

Various methods such as vibroforming and pump forming can be used.

5. Low coefficient of thermal expansion and excellent heat resistance

Not prone to cracking and peeling, suitable for use in environments with large temperature fluctuations.

Main areas of application of low-cement concrete

1. Ferrous metallurgy

Blast furnace outlet channel, ladle, lining of iron ladles

Working layer of the intermediate ladle of continuous casting of steel

Electric arc furnace lid, furnace walls, furnace floor

2. Non-ferrous metallurgy

Aluminum electrolyzer side wall, furnace lining

Reflector furnace for copper smelting, converter

3. Cement and petrochemical industry

Rotary cement kiln cooler, decomposition kiln, cast iron kiln throat ring

Incinerator, lining of petrochemical cracking furnaces

4. energy

Coal-fired boiler furnace chamber, chimney, cyclone separator lining