MgO based brick are used in regenerators of glass furnaces due to their high thermal conductivity, high heat capacity, creep resistance and resistance to alkalis and basic slags. These products are typically formulated with dead-burned and fused magnesia and/or combinations of each. The specific MgO level and quality depends on the application and area of use in the regenerator. In addition the MgO is often combined with chrome ore, or zircon in order to enhance certain properties for application in different zones of the regenerator.
Top-Line MZ97, MZ97F, MZ98 and MZ98F: All of these MgO brick qualities are based on high purity DBM and Fused MgO and or combinations of both. The products contain low levels of impurities and have excellent creep and corrosion resistance to the alkaline environment found in the top zone of the regenerator. Qualities such as MZ97F and MZ98F are based on fused MgO and offer exceptional corrosion resistance for severe applications.
Top-Line MZ95 and MZ96: These products are designed for use in the middle zone of the glass regenerators where the temperatures are lower. Both qualities have good refractoriness under load and exhibit good resistance to corrosion by alkalis.
Top-Line Fired Magnesia Brick
Top-Line Magnesia Zircon Brick
Magnesia Zircon brick are based high purity DBM or Fused MgO and Zircon (ZrSiO4). During the firing of the bricks the MgO will react with the Zircon to form Fosterite (Mg2SiO4) and Zirconia (ZrO2). Both of these phases are formed in the matrix of the brick and exhibit excellent corrosion resistance to alkalis. These brick are typically applied to the high temperature top checkers and middle checker area where condensate corrosion and penetration of refractories can occur. Magnesia Zircon brick are also chrome free and after use can be disposed of easily.
Top-Line M75Z Checker:This product is based on high purity DBM and Zircon. It is designed for application in the top checker area and the middle checkers due to it excellent corrosion to alkalis and high temperature properties.
Top-Line M75FZ Checker: This MgO based brick is formulated with high purity fused MgO and Zircon in order to achieve improved corrosion resistance and high temperature creep properties. The product is typically used in condensation zone of the regenerator in glass furnaces that have severe operating conditions.
Top-Line Direct Bonded Magnesia Chrome Brick
High fired Magnesia Chrome brick with approximately 60% MgO have been shown to give good performances in the various types of copper furnaces (i.e. Pierce-Smith, anode furnaces and Kaldo converters). These products are chemically compatible with the copper slags, and have physical properties that meet the copper production process conditions. Magnesia chrome brick used in these applications typically have low porosity and permeability to resist slag infiltration and corrosion, good thermal shock and erosion resistance (tuyere zones).
YNCR has developed a line of MgO-Chrome products in order to meet the requirements of the various copper production applications. The types of MgO-Chrome brick range from direct bonded brick to re-bonded and semi-rebonded brick that are based on combinations of high purity MgO, chrome ore and Fused MgO-Chrome raw materials. These products are formulated and fired to temperatures in excess of 1720oC to achieve excellent high temperature properties and corrosion resistance to meet the demands of the various copper production processes.
Top-Line Fired MgO-Spinel Brick
Top-Line XF: These products are based on high purity MgO, synthetic fused spinel and/or alumina. Two types of fused spinel materials used are (1) based on MgO and Al2O3 or (2) Alumina and iron oxide (Hercynite). Fired brick made with combinations of these raw materials have excellent thermal mechanical properties and are compatible with the cement production process conditions.
Top-Line MF : A fired Magnesia Spinel brick that is formulated with high purity MgO and synthetic fused Hercynite spinel (Alumina – Iron oxide spinel). This product has good thermal mechanical properties and good coating characteristics. In addition the product has low permeability which makes it resistant to infiltration by alkali salts and cement liquid phases. Top-Line MF is recommended for the burning and upper transitions zones.