Properties of magnesia ferrous spinel bricks

Magnesia ferrous spinel bricks are a new type of chrome-free refractory for cement rotary kiln that first developed in Europe in the late 1990s. This product is made of divalent iron-aluminum spinel (FeO·Al2O3) and high-purity magnesia as the main raw materials. During the firing process, the firing temperature and firing atmosphere are strictly controlled to ensure that the iron oxide in the brick is composed of FeO. form exists.

 

During the use of magnesia ferrous spinel bricks, a layer of highly viscous calcium-iron and calcium-iron-aluminum compounds is formed on the hot surface of the brick, which is very easy to hang on the kiln skin. In addition to the excellent kiln skin performance of magnesia-chromium bricks, magnesia ferrous spinel bricks also have high thermomechanical and thermochemical properties. In some European countries, it has been widely used in the firing zone and transition zone of cement rotary kilns, and it has become a new type of chromium-free refractory that may completely replace magnesia-chrome bricks. The physical and chemical indicators of magnesia ferrous spinel bricks produced by a refractory manufacturer are: MgO86%, Al2O33%, Fe2O38%, CaO1.7%, SiO20.8%, apparent porosity 15%, bulk density 3.06g/cm3, The normal temperature compressive strength is 66MPa, and the high-temperature flexural strength (1400℃) is 2.5MPa.

Main uses of magnesia ferrous spinel bricks

It is used to replace magnesia-chromium sand to make magnesia ferrous spinel bricks for cement rotary kiln, which not only avoids chromium pollution but also has good spalling resistance; secondly, it is used to make ladle castables, which greatly improves the corrosion resistance of steel plate linings. It is widely used in refractory materials for steelmaking. 

 

At present, some refractory enterprises in Liaoning, Henan, and other places in my country produce magnesia ferrous spinel bricks. It is believed that this magnesia composite refractory will be produced and applied in large quantities in my country in the future.