Magnesium-Chromium Refractory Bricks Used in the Non-Ferrous Metal Industry

The refractory bricks used in the non-ferrous metal industry mainly include magnesia-chromium refractory bricks, silicon carbide refractory bricks, corundum refractory bricks and high alumina refractory bricks. Each refractory brick is widely used in copper smelting, nickel smelting and lead smelting industries. The characteristics of the three metal smelting are as follows. The flue gas contains a large amount of SO2 gas. The melt contains not only oxides, and metals, but also many sulfides. The melt melting temperature is relatively low, but the melt flow is good. The slag is FeO-SiO2 slag, and the amount of slag is very large. The temperature in the furnace fluctuates greatly, and the melt scours the refractory bricks seriously. Chromium-magnesium refractories have strong resistance to iron-silicon slag erosion and SO2 erosion, and also have good resistance to melt erosion.

Magnesium-chromium refractory bricks are refractory brick products with magnesium oxide (MgO) and chromium trioxide (Cr2O3) as the main components, and periclase and magnesia-chromium spinel as the main minerals. Magnesia-chromium refractory bricks have the advantages of high refractoriness, high temperature strength, strong resistance to alkaline slag erosion and strong thermal shock resistance. Generally used in non-ferrous metal smelting furnaces.

Magnesia Chrome Brick for Non-Ferrous Smelting

There are many types and varieties of magnesia-chromium refractory bricks. According to its combination, it can be divided into ordinary magnesia-chrome bricks, directly combined magnesia-chrome bricks, combined with magnesia-chrome bricks, semi-recombined magnesia-chrome bricks, and so on.

(1) Ordinary magnesia-chrome bricks, namely silicate-bonded magnesia-chrome bricks. The impurity content of CaO and SiO2 is high, and the sintering temperature is 1550℃. Made directly from magnesia and chrome ore. The microstructure of this type of refractory brick shows that granular chrome ore is wrapped by a finely dispersed magnesia binder. There is also a silicate filler with a lower melting point between the grains. This results in low high-temperature strength and poor slag resistance. With the development of non-ferrous metal pyro-enhanced smelting technology, this brick has been completely eliminated.

(2) Directly combined with magnesia-chrome bricks, it is made from purer magnesia and chrome ore concentrate. The impurity content of SiO2 and CaO in the brick is low, and the firing temperature used is also above 1700 °C. The microstructure of the brick shows that the direct bonding rate of high melting point minerals is high, and the high-temperature performance, erosion resistance, and erosion resistance are obviously better than ordinary magnesia-chrome bricks.

(3) Combined with magnesia-chrome brick, it is a magnesia-chrome brick made of fused magnesia-chrome material. The impurity content in the raw material is less, and the firing temperature is also above 1750℃. The microstructure and morphology of the bricks show that the distribution of spinel components is relatively uniform in the rotation, which effectively improves the anti-scour ability.

(4) Semi-recombined magnesia-chrome brick is a magnesia-chrome brick made of synthetic raw materials as particles, and chrome concentrate and magnesia as a fine powder. The firing temperature is above 1700°C. The microstructure and morphology of the bricks show that the crystals are mainly bonded directly, and they have good thermal shock resistance.

For free samples and quotations of magnesia-chrome refractory bricks used in the non-ferrous metal industry, please contact Sales@rongshengrefractory.com.