Calcined flint clay is widely used in refractories, and the following are its main application fields:

I. Low porosity clay brick

Calcined flint clay is an important raw material for making clay bricks with low porosity. By using flint clay clinker and soft clay, a low porosity clay brick with porosity of 13.6% can be manufactured by co-grinding fine powder and mud blending. This kind of brick has high room temperature compressive strength (71MPa) and load softening temperature (1480℃), and is suitable for lining of high temperature furnaces.

II. Anti-spalling bricks

Using high-quality calcined flint clay clinker as aggregate, adding sillimanite concentrate and silicon carbide and other raw materials, the spalling-resistant brick with thermal shock resistance greater than 40 times can be prepared. This kind of brick has excellent thermal shock resistance and is suitable for furnace lining in high temperature environment.

III. Castable materials

Flint clay-bauxite castable has excellent high temperature resistance, acid and alkali corrosion resistance and thermal shock resistance, and is widely used in construction, metallurgy, petrochemical and other industries. This castable can be used as lining of converter, blast furnace and other equipment, and can withstand mechanical impact and chemical erosion in high temperature environment.

IV. paint spraying and plastic refractory

Calcined flint clay-based paint spraying and plastic refractory are widely used in repairing the lining of blast furnace and the top of low-temperature section of heating furnace because of their low cost and excellent performance. After sintering at 600℃, 1000℃ and 1300℃, flint clay-based paint spraying has good flexural strength and compressive strength, which can partially replace bauxite-based paint spraying.

V. Unformed refractories

Calcined flint clay can also be used to produce unshaped refractories, such as refractory slurry and paint spraying. These materials have good construction performance and high temperature stability, and can meet the needs of complex environment.

VI. Ceramic fibers and aluminum silicate fibers

Calcined flint clay is an important raw material for producing ceramic fiber and aluminum silicate fiber. These fibers have excellent thermal insulation and high temperature resistance, and are widely used as thermal insulation materials in aerospace, automobile, construction and other fields.

VII. Other refractory products

Calcined flint clay can also be used to manufacture refractory products such as refractory crucibles, kiln furniture and saggers. These products have high strength, low water absorption and good chemical stability, and are suitable for high temperature environment.

To sum up, calcined flint clay is widely used in the field of refractories because of its high refractoriness, low impurity content and excellent physical and chemical properties, and is an important raw material for producing a variety of refractory products.