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In this section, we will review articles and texts related to the construction industry and its development, aiming to contribute in a small way to the growth of the building sector.
In this section, we will review articles and texts related to the construction industry and its development, aiming to contribute in a small way to the growth of the building sector.
Refractory Clay:
The use of bricks as a construction material in Iran has a history of several thousand years. Despite the passage of centuries, bricks remain widely used, adding unique and innovative colors and forms to the built environment.
The term refractory clay refers to certain types of heat-resistant soils that can withstand temperatures of at least around 1500°C.
Fire bricks (Refractory facing bricks) are a type of brick with high temperature resistance, typically fired at around 1500°C. Depending on the materials used in their composition, refractory bricks come in different types and can tolerate varying temperature ranges.
Fire bricks (Refractory facing bricks) are a type of brick with high temperature resistance, typically fired at around 1500°C. Depending on the materials used in their composition, refractory bricks come in different types and can tolerate varying temperature ranges.
The refractory materials used in making these bricks must maintain their physical and chemical properties under high temperatures and environmental conditions. Due to their heat resistance, refractory bricks are also used in fireplaces and other applications that require operation at high temperatures.
What is Refractory Clay?
Refractory clay refers to clay with a high alumina content. The alumina content in refractory clay is generally above 25%, with small amounts of impurities such as alkalis and iron oxides.
Refractory clay refers to clay with a high alumina content. The alumina content in refractory clay is generally above 25%, with small amounts of impurities such as alkalis and iron oxides.
Refractory clay is widely used to produce:
Fire bricks
Furnace linings and repairs
Glass and ceramic production
Various types of kilns
Insulating bricks
Refractory mortars and special mixtures
Other specialized products
Fire bricks
Furnace linings and repairs
Glass and ceramic production
Various types of kilns
Insulating bricks
Refractory mortars and special mixtures
Other specialized products
Characteristics of Refractory Clay:
Can withstand temperatures of at least 1515°C
Contains 23–34% alumina (Al₂O₃), about 60% silica (SiO₂), and around 12% volatile materials
Contains water, which is released during firing
May include up to 25% iron oxide and minor amounts of CaO, MgO, K₂O, and Na₂O
High-quality refractory clays are single-mineral and dominated by kaolinite, with some quartz and carbonate impurities
Types of Refractory Clay:
Aluminosilicate
Alumina-rich
Fast-firing (low refractory)
Slow-firing (high refractory)
Can withstand temperatures of at least 1515°C
Contains 23–34% alumina (Al₂O₃), about 60% silica (SiO₂), and around 12% volatile materials
Contains water, which is released during firing
May include up to 25% iron oxide and minor amounts of CaO, MgO, K₂O, and Na₂O
High-quality refractory clays are single-mineral and dominated by kaolinite, with some quartz and carbonate impurities
Types of Refractory Clay:
Aluminosilicate
Alumina-rich
Fast-firing (low refractory)
Slow-firing (high refractory)
Notes:
Fast-firing clays often contain montmorillonite, hydrous silicates, and impurities like quartz, mica, and carbonates. They have lower alumina and higher silica content.
Slow-firing clays generally contain haloisite, kaolinite, montermite, hydrosil, and impurities such as quartz and feldspar.
Refractory Clay in Iran:
Today, Iran is the largest producer of refractory clay in the Middle East. However, many clays in Iranian mines contain impurities far above permissible limits and cannot be used raw to meet domestic industrial needs.
Applications of Refractory Clay:
Some common uses include:
1_ Glaze, insulator, porcelain, tile, and ceramic production
2_ Furnace linings and mold making
3_Manufacturing sanitary ceramics and construction materials
4_Iron smelting furnaces, ceramic kilns, electric kilns, steam boilers, glass containers, and fireplaces
Fast-firing clays often contain montmorillonite, hydrous silicates, and impurities like quartz, mica, and carbonates. They have lower alumina and higher silica content.
Slow-firing clays generally contain haloisite, kaolinite, montermite, hydrosil, and impurities such as quartz and feldspar.
Refractory Clay in Iran:
Today, Iran is the largest producer of refractory clay in the Middle East. However, many clays in Iranian mines contain impurities far above permissible limits and cannot be used raw to meet domestic industrial needs.
Applications of Refractory Clay:
Some common uses include:
1_ Glaze, insulator, porcelain, tile, and ceramic production
2_ Furnace linings and mold making
3_Manufacturing sanitary ceramics and construction materials
4_Iron smelting furnaces, ceramic kilns, electric kilns, steam boilers, glass containers, and fireplaces