The Magnesium Oxide Content of Alkaline Refractory Bricks

Alkaline refractory bricks are a kind of refractory material mainly composed of magnesia raw materials. They have excellent slag erosion resistance, thermal shock resistance and high temperature structural stability. In industries such as metallurgy, building materials, and chemicals, alkaline refractory bricks are widely used in the lining of high-temperature equipment such as furnaces, cement rotary kilns, and glass kilns. Rongsheng Refractory Materials Manufacturer has summarized a variety of commonly used alkaline refractory bricks based on years of production and sales experience. So, do you know the magnesium oxide content of alkaline refractory bricks?

Magnesite Bricks from Rongsheng Manufacturer
Magnesite Bricks from Rongsheng Manufacturer

Free Quote

    Free Quote

    Your Name (required)


    Your Email (required)

    Your Phone

    Required Products (required)

    Enquiry Information

    Various Alkaline Refractory Bricks

    • Magnesia-Chrome Brick: Magnesia-Chrome Brick is an alkaline refractory brick made of magnesia and chromite as the main raw materials and sintered at high temperatures. Magnesia chrome bricks have the advantages of high melting point, high strength, and high resistance to slag erosion. Suitable for working conditions under high temperature, high pressure, and strong alkali environment.
    • Magnesia-alumina brick: Magnesia-alumina brick is an alkaline refractory brick made of magnesia and alumina as the main raw materials, adding an appropriate amount of additives, and sintering at high temperature. Magnesia-alumina bricks have good thermal shock resistance, slag erosion resistance, and high-temperature structural stability. Suitable for lining of high-temperature equipment such as cement rotary kilns and glass kilns.
    • Magnesia-calcium brick: Magnesia-calcium brick is an alkaline refractory brick made of magnesia and lime as the main raw materials, adding an appropriate amount of additives, and sintered at high temperature. Magnesia-calcium bricks have high thermal shock resistance and slag erosion resistance. Suitable for high-temperature equipment in steel, nonferrous metals and other industries.
    • Magnesia dolomite brick: Magnesia dolomite brick is an alkaline refractory brick made of magnesia and dolomite as the main raw materials, adding an appropriate amount of additives, and sintering at high temperature. Magnesium dolomite bricks have good thermal shock resistance, slag erosion resistance, and high-temperature structural stability. Suitable for lining of high-temperature equipment such as cement rotary kilns and glass kilns.
    Magnesia Chrome Bricks for Furnaces
    Magnesia Chrome Bricks for Furnaces

    Free Quote

      Free Quote

      Your Name (required)


      Your Email (required)

      Your Phone

      Required Products (required)

      Enquiry Information

      Magnesium Content of Alkaline Refractory Bricks

      • Magnesia chrome bricks: The magnesium content of magnesia chrome bricks is generally between 60% and 80%, and the chromium content is between 20% and 40%. The magnesium content of magnesia-chrome bricks is high, which is beneficial to improving its resistance to slag erosion and high-temperature structural stability.
      • Magnesia-alumina bricks: The magnesium content of magnesia-alumina bricks is generally between 50% and 70%, and the aluminum content is between 20% and 40%. The magnesium content of magnesia-alumina bricks is moderate, which is beneficial to improving its thermal shock resistance and slag erosion resistance.
      • Magnesia-calcium bricks: The magnesium content of magnesia-calcium bricks is generally between 50% and 70%, and the calcium content is between 20% and 40%. The magnesium content of magnesia-calcium bricks is moderate, which is beneficial to improving its thermal shock resistance and slag erosion resistance.
      • Magnesium dolomite bricks: The magnesium content of magnesia dolomite bricks is generally between 50% and 70%, and the dolomite content is between 20% and 40%. The magnesium content of magnesia dolomite bricks is moderate, which is beneficial to improving its thermal shock resistance and slag erosion resistance.

      Precautions

      When selecting alkaline refractory bricks, the appropriate type and magnesium content should be selected based on specific working conditions and requirements.

      When laying alkaline refractory bricks, attention should be paid to controlling the size of the brick joints, generally between 2-3mm. Excessive brick joints will lead to increased heat loss, while brick joints that are too small are not conducive to the expansion and contraction of the brick body.

      During the masonry process, special anchors should be used to fix the refractory bricks on the base body to prevent the bricks from loosening and falling off. The selection and installation of anchors should comply with design requirements and construction specifications.

      After the masonry is completed, the bricks should be trimmed and excess mortar should be removed to make the brick surface smooth and beautiful.

      In short, alkaline refractory brick is a refractory material with excellent properties and is widely used in high-temperature equipment in metallurgy, building materials, chemical industry and other industries. When selecting and using alkaline refractory bricks, the appropriate type and magnesium content should be selected according to the specific working conditions and requirements to ensure the safe and stable operation of the equipment.

      Rongsheng Checker Bricks for Glass Kilns
      Rongsheng Checker Bricks

      Free Quote

        Free Quote

        Your Name (required)


        Your Email (required)

        Your Phone

        Required Products (required)

        Enquiry Information

        Magnesite Checker Bricks for Glass Kiln

        In the refractory industry, refractory bricks with MgO as the main component and periclase as the main crystal phase are collectively called alkaline refractory bricks. Alkaline refractory bricks are mainly used in thermal kilns used in cement, glass, ferroalloy and other industries.

        In glass-melting furnaces, alkaline refractory bricks are mainly used as regenerator checker bricks. Its thermal conductivity is large, its service life is long, and its volume density is high, which increases the heat storage in the regenerator. The porosity of alkaline refractory bricks is low, and the thermal expansion coefficient increases linearly as the temperature rises. It is the largest among various refractory materials. Pay attention to leaving enough expansion joints during use.

        Alkaline refractory bricks are non-insulators above 900°C and have very good electrical conductivity and cannot be used as high-temperature insulating materials.

        Alkaline refractory bricks cannot be used in gas regenerators. And long-term contact with water vapor at 40~160℃ will cause hydration, which will cause the brick structure to become loose and damaged. So keep it dry during storage. Before laying the magnesite checkered bricks, the regenerator must be dried.

        At present, including ordinary magnesia bricks, magnesia refractory materials also have the following types.

        • Ordinary magnesia bricks. It is made of sintered magnesite as raw material and sintered. The content of MgO is about 91%. It is a magnesium refractory product directly combined with silicate and is widely produced and used.
        • Directly bonded magnesia bricks. It is made of high-purity sintered magnesia as raw material and sintered. The content of MgO is more than 95%. It is a magnesia refractory product directly bonded between periclase grains.
        • Magnesia silica brick. It is made of high-silicon sintered magnesite as raw material and sintered. SiO2 content is 5%~11%, it is a magnesia refractory product combined with forsterite.
        • Forsterite Bricks. Forsterite refractory material is a refractory material with forsterite as the main crystal phase. It is mostly made of peridotite and pure peridotite as the main raw materials, and the formed products are called forsterite bricks.

        Buy high-quality alkaline refractory bricks, magnesia bricks, magnesia checker bricks for glass kilns, metallurgical kilns, etc. Please choose Rongsheng refractory material manufacturer. Rongsheng manufacturer, product quality is reliable and delivery speed is guaranteed. Moreover, comprehensive customer service effectively guarantees the service life of the refractory furnace lining and saves production costs for customers.

          Get Free Quote

          Your Name (required)

          Your Email (required)

          Your Phone

          Required Products (required)

          Enquiry Information

          Corundum Mullite Bricks Used in the Burner of the Sleeve Lime Kiln

          Generally, the burner of the sleeve lime kiln is made of magnesia refractory bricks. However, due to the fact that it is prone to breakage within a year of use, the service life of the burner brick is not synchronized with the service life of the kiln body. The burner brick of the sleeve lime kiln broke 1/3 in less than one year, and the service life of the lime kiln was more than 3 years. Therefore, the service life of the burner brick is not synchronized with the service life of the kiln body. Although the fracture of burner bricks does not affect the use of lime kilns, it has certain negative effects on the calcination process. Therefore, it is necessary to study the corundum mullite bricks used in the burner of the sleeve lime kiln.

          The reason why the burner brick is easy to break is that the burner brick is made of magnesia refractory brick. In addition to excellent high-temperature resistance and lime resistance, the alkaline material also has the following unfavorable factors, which may lead to premature fracture.

          1. Magnesium refractory has large thermal expansion and poor thermal shock resistance. The burner brick is scoured by the hot air flow of the flame, the thermal shock environment is harsh, and cracks caused by thermal shock are prone to occur.
          2. Due to the large thermal expansion coefficient, the thermal stress of the magnesia refractory is high. When there is a local stress concentration, the fracture is easy to occur.
          3. Magnesium refractories are easy to hydrate, resulting in bulging and cracking. Construction is greatly affected by environmental conditions. Improper baking is also prone to cracking, resulting in falling blocks. In cold and humid weather, the water in the fire mud is not easy to remove, and it is easier to hydrate the bricks. Therefore, it has strict requirements on construction environmental conditions and baking.
          4. The thermal strength of magnesia refractories is low, and it is prone to creep under thermal stress.
          Corundum Mullite Bricks Used in the Burner of the Sleeve Lime Kiln
          Corundum Mullite Bricks Used in the Burner of the Sleeve Lime Kiln

          Free Quote

            Free Quote

            Your Name (required)


            Your Email (required)

            Your Phone

            Required Products (required)

            Enquiry Information

            The improvement of burner brick material selection of burner brick prefabricated parts made of corundum mullite refractory castable has the following advantages.

            • The main crystal phase of corundum mullite refractory castable is corundum and mullite. Corundum has a high melting point of 2050°C, its hardness and strength can resist high temperature and airflow erosion, and it has excellent high temperature wear resistance. The melting point of mullite is also higher than 1840 ° C, which is characterized by a small thermal expansion coefficient and a needle-column mosaic structure, which has good thermal shock resistance. The refractory castable composite of corundum phase and mullite phase has the advantages of both, which can effectively resist the erosion of the burner brick by the hot air flow of the flame. At the same time, it can withstand the harsh thermal shock environment and prevent the burner brick from breaking.
            • Corundum mullite refractory castables do not have hydration problems. The construction is less affected by the environment, and the requirements for construction conditions are not harsh. And pouring, curing, and heat treatment can be carried out by the supplier, and the quality can be easily guaranteed. No hydration cracking during construction and baking.
            • The burner brick is a special-shaped brick, which is not easy to be machine-pressed. Using the casting method, it is easy to form integral or separate parts and to achieve precise control of shape and size. The critical particle size of machine-pressed bricks is limited, generally 5 mm. The critical particle size of the castable can be as large as about 20 mm, which is conducive to the stability of the structure and the improvement of thermal shock resistance.
            • When the burner brick is in use, since the gas (or fuel oil) is sprayed into the furnace, the CaO dust in the furnace is not easy to adhere to the burner cavity, and the reaction between CaO and the Al2O3-SiO2 material will not occur. Even if there is a small amount of CaO attached to the burner brick, the content of A12O3 in the burner brick is relatively high (greater than 75%), while the content of SiO2 and CaO is relatively low. According to the A12O3-SiO2-CaO ternary phase diagram, the reaction temperature is around 1500℃. It can be considered that the solid-phase reaction of Al2O3-SiO2-CaO does not easily occur at the working temperature of the lime kiln.

            Summary: Through the analysis of the reasons for the phenomenon that the burner of the sleeve kiln is easy to break, and according to the combustion process of the lime kiln calcination zone, the structural design of the lining refractory material, etc. Production of corundum mullite refractory castable prefabs suitable for sleeve kiln burners. The corundum mullite bricks used in the burner of the sleeve lime kiln can synchronize the service life of the burner brick with the service life of the kiln body.

              Get Free Quote

              Your Name (required)

              Your Email (required)

              Your Phone

              Required Products (required)

              Enquiry Information