Alkali resistant bricks are a kind of new type semi-silica refractory material which have good performance in alkali-resistance erosion. At a certain temperature, alkali-resistant bricks can react with alkali quickly in the kiln material and react with brick surface at the same time to form a high viscosity glaze layer, preventing continued infiltration and “alkali cracking” damage of alkali-proof bricks. Alkali-resistant bricks are mainly used in open hearth furnaces, oxygen-blowing converters, electric furnaces, non-ferrous metal smelting equipment and glass industries, as well as some high-temperature equipment. Alkali resistant bricks include common type alkali-resistant bricks, high-strength type alkali-resistant bricks, arch type alkali-resistant bricks and insulation type alkali-resistant bricks. So everyone who needs alkali-resistant bricks series or have any questions about them, welcome to contact us feel free for free quotation.
What are Alkali Resistant Bricks
Alkali resistant brick is a new type alkali-resistant clay (or semi-silica) refractory material with excellent alkali-resistant corrosion. It is also named after cement kiln alkali resistant brick due to its properties. Alkali resistant brick for cement kiln refers to the fireclay brick with low alumina refractory clay as the primary raw material, in possession of alkali corrosion resistance in cement kiln system. The main raw materials of alkali resistant bricks contain coke gems, pyrophyllite, silica stone and so on.
Properties of Alkali Resistant Bricks
Alkali resistant bricks have the advantages of high softening temperature load degree, high temperature structure performance and good thermal shock stability. Meanwhile, it has a strong ability to resist erosion, not easy peel off and wear resistance. It overcomes the shortcomings of poor thermal shock resistance of common high alumina bricks, low erosion resistance of cement clinker, and low softness of phosphoric acid bricks. Therefore, alkali-resistant brick has the property of high strength, stable volume, good alkali corrosion resistance, etc. It is more applied in cement kiln preheater, decomposition furnace, tertiary air duct.
- Low thermal conductivity
- High compressive strength
- Excellent alkali corrosion resistance
- Volume stable
- High softening temperature load degree
- Good thermal shock stability
- High refractoriness
Classifications of Alkali Resistant Bricks
Alkali resistant bricks generally can be classified into the following four types:
- Common type alkali-resistant bricks: Common alkali-resistant bricks are a kind of refractory bricks that use silica stone, coke gems and appropriate amounts of additives to improve the microstructure of the products. They have the characteristics of low thermal conductivity, high compressive strength, and excellent alkali corrosion resistance.
- High-strength type alkali-resistant bricks: High strength type alkali-resistant bricks are made of silica stone, coke gemstone and an appropriate amount of additives to improve the compressive strength on the basis of common type alkali-resistant bricks. They are featured with high strength, stable volume and good alkali corrosion resistance.
- Arch type alkali-resistant bricks: Alkali-resistant brick of 1350℃ is excellent, have high refractoriness, stronger resistance to alkaline slag, high thermal strength and thermal stability, which is mainly used in the top position of industrial arches, so it is also generally called arch type alkali-resistant brick.
- Insulation type alkali-resistant bricks:Insulation type alkali-resistant bricks have good insulation effect.
Specification of Alkali Resistant Bricks
Brand/Item | Al2O3
(%) ≥ |
SiO2
+SiC (%) ≥
|
Apparent Porosity
(%) ≤ |
Cold Crushing Strength
(MPa) ≥ |
0.2MPa Softing Temperasture Load Degree
T0.6(℃) ≥ |
Thermal Shock Resistance
(1100℃) Water Quenching, Cycle ≥ |
Thermal Conductivity
(350℃) ≤ |
Thermal Expansion Rate
(900℃) |
Common type alkali resistant bricks | ||||||||
RSRK-O | 25-35 | 60-70 | 25 | 25 | 1350 | 10 | 1.3 | 0.7 |
High-strength type alkali resistant bricks | ||||||||
RSRK-H | 25-35 | 60-70 | 20 | 60 | 1300 | 5 | 1.4 | – |
Arch type alkali-resistant bricks | ||||||||
RSRK-A | 25-35 | 60-65 | 25 | 30 | 1400 | 10 | 1.3 | – |
Insulation type alkali-resistant bricks | ||||||||
RSCB-20 | 20-30 | 60-67 | 30 | 15 | 1200 | 5 | 0.75 | 0.6 |
RSCB-30 | 20-30 | 60-67 | 30 | 20 | 1200 | – | 0.75 | – |
Applications of Alkali Resistant Bricks
From above descriptions, we know that alkali resistant bricks can be divided into four types, so each type can be applied into different parts in cement kiln industry.
- Common alkali-resistant bricks are mainly used in preheaters and decomposition zones of cement rotary kiln.
- High-strength alkali-resistant bricks are mainly applied in cement kiln preheaters, decomposing furnaces, tertiary air ducts, vertical ascending flue, cyclone straight tubes and cones.
- Arch type alkali-resistant bricks are mainly used for the cement kiln preheaters and the tertiary air duct of the decomposition furnace.
- Insulation type alkali-resistant bricks are mainly used for the kiln mouth, kiln door cover and cooling machine of the cement kiln.
Types of Alkali Resistant Bricks
Alkali resistant bricks have lots of different kinds of varieties such as magnesia brick, magnesia chrome brick, magnesium zirconium brick, magnesium aluminum brick, dolomite brick, magnesium calcium brick, magnesium aluminum spinel brick, etc. Alkali resistant brick series mainly regard magnesium oxide and calcium oxide as the main components.
Supplier of Alkali Resistant Bricks
RS company’s alkali resistant brick series have been acknowledged by domestic and foreign manufacturers. Alkali resistant bricks can be divided into common type alkali-resistant bricks, high-strength type alkali-resistant bricks and insulation type alkali-resistant bricks according to different properties. What’s more, common type alkali-resistant bricks can also be classified into common type alkali-resistant bricks and arch type alkali-resistant bricks based on the application location. The size of standard alkali resistant bricks are 230*114*65 mm, RS manufacturer can customize products according to customer needs. So don’t be hesitate to contact us for more details.