Description

What is refractory silicon mullite bricks?

Retractory Silicon mullite bricks are made of special high-alumina bauxite and silicon carbide as the main raw materials, and is made of andalusite matrix, grinding aid, zircon sand and other auxiliary materials (there are also cases where sillimanite, mullite, high-alumina bauxite clinker is the main raw material or other auxiliary materials). It is a refractory brick made by a special sintering process. It is mostly called silicon-mullite brick in the building materials industry, and can also be called high-alumina silicon carbide brick, aluminum oxide-silicon carbide brick, etc.. in other industries. It is a silicon carbide-mullite product.

• According to the load softening temperature index, it is divided into three grades: GM1650, GM1680, and GM1550.
• According to its composition and use, it can be divided into: wear-resistant high-alumina brick; silicon-molybdenum wear-resistant brick; reinforced wear-resistant high-alumina brick; phosphate high-alumina wear-resistant brick

Technical parameter

De Wikipédia: Fire brick

Performance characteristics of Refractory Silicon Mullite Bricks

• Dense structure: The main crystal phase of silicon molybdenum refractory bricks is composed of corundum (Dureté de Mohs 9.0 – 9.2), silicon carbide (Dureté de Mohs 9.0 – 9.5), and mullite (Dureté de Mohs 7.0 – 7.5). The finished product has a high structural density. , the bulk density is generally 2.7 – 3.0g/cm³.
  Its normal temperature wear resistance depends on the strength and compactness of the structure. The high strength and density make it have better wear resistance. When the lining of the cement rotary kiln is subject to rolling friction by the material, the wear resistance is significantly higher than the anti-flaking high-aluminum lining. Bricks and magnesia-alumina spinel bricks.
• Température de ramollissement sous charge élevée: The load softening temperature of silica molybdenum bricks is above 1450℃, and can be as high as above 1650℃. There are certain differences in the load softening temperature of different products.
• Strong corrosion resistance: the structure is dense, and the brick surface can form a continuous dense layer of SiO₂ to prevent the penetration of molten substances. En outre, Al₂O₃, SiC, and SiO₂ have stable chemical properties and do not react violently with SO₂, O₂, CO₂ and other gases produced in the kiln, nor do they chemically react with cement materials, and have strong corrosion resistance.
• Good thermal shock stability: Since silicon molybdenum bricks contain a certain amount of SiC, SiC has high thermal conductivity and a relatively small thermal expansion coefficient, the thermal shock stability of silicon molybdenum refractory bricks is significantly improved. The 1100°C water-cooling test was completed after 10 fois. Above, some as high as 46 fois. It does not peel or break when used in cement rotary kilns, which can extend the service life of the kiln.
• Good thermal insulation effect: The thermal conductivity of silica molybdenum bricks [2.3 – 2.5Avec(m˙K)] is lower than that of alkaline products [2.69 – 2.74Avec(m˙K)]. It is suitable for secondary firing in large rotary kilns. When used in belts, transition zones, preheating zones, kiln tails, tertiary air ducts, decomposition furnaces, etc., compared with alkaline bricks, the surface temperature of the cylinder is reduced by more than 100°C, and the heat insulation effect is better.

Refractory Silicon Mullite Bricks price

Difference between Refractory Silicon Mullite Bricks and Silicon Mullite red brick

The main difference between silica-molybdenum brick and silica-molybdenum red brick lies in the raw material composition, performance characteristics and application parts.

Silica-molybdenum brick is a fired brick with mullite (3Al2O3·2SiO2) and silicon carbide (SiC) as the main minerals2. On the other hand, silica-molybdenum red brick is based on conventional silica-molybdenum brick, and by adding andalusite raw materials, it further enhances the thermal shock resistance and thermal insulation performance and increases the load softening temperature.

The difference between mullite brick and sillimanite brick

The main difference between sillimanite and mullite lies in their chemical composition, crystal structure and typical applications.

1. Composition chimique: The main components of sillimanite are SiO2 and Al2O3, while mullite contains more Al2O3 and SiO2, and its chemical formula is 3Al2O3·2SiO2.
2. Crystal structure: Sillimanite is a high-aluminum mineral, and mullite is a silicate mineral.
3. Typical application: Sillimanite has important applications in the field of ceramics, especially in the production of honeycomb ceramics and mullite porcelain. Mullite is widely used as a refractory material due to its excellent refractory properties, such as in high-temperature industrial kilns or boilers.

Refractory Silicon Mullite Bricks cost

Where is Silicon Mullite Brick used?

Silicon Mullite Brick is mainly used in transition zones, decomposition zones and coolers of small and medium-sized cement kilns.

Silicon Mullite bricks used in the upper transition zone of a 5000t/d new dry-process water kiln can achieve a service life of 12 months, and used in the upper transition zone of a 2500t/d new dry-process cement kiln can achieve a service life of 1 à 2 years, which is equivalent to 150% à 200% of magnesia-alumina spinel bricks.