A comprehensive understanding of refractories acidity and basicity
As we all know that refractories are of many chemical and physical properties, but one of them -- acid-base properties are worthy of our careful learning.
Acid refractory material determines its use temperature environment, anti slag corrosion ability, refractoriness under load, changes in the volume after repeated burning and thermal shock resistance. A comprehensive understanding of the acidity of the refractory material can achieve the best material, be just perfect use.
How is the acidity refractory material? Acid refractory usually refers to SiO2 content more than 93%. Basic refractory materials generally refer to the refractory material to Magnesium Oxide or Magnesium Oxide and calcium oxide as the main component. The main characteristic of acid refractories is erosion resistant acid slag at high temperature, but easy to react with alkaline slag. Acid refractory materials are commonly used silica refractory bricks and clay bricks. Silicon refractory brick is siliceous materials silica containing more than 93%, raw materials used in silica, silica refractory bricks, the acid resistance of slag erosion ability, high refractoriness under load, the volume does not shrink after repeated burning, or even a slight expansion; but vulnerable to the erosion of basic slag, thermal shock resistance difference. Silicon refractory brick is mainly used for thermal equipment of coke oven, glass kiln, acid furnace etc. Clay refractory bricks with refractory clay as the main raw material, containing 30% ~ 46% of alumina, is a weak acid refractories, good thermal shock resistance, resistance to acid slag, wide application. Basic refractory degree is higher, the ability to resist the strong alkaline residue. For example, magnesia brick, magnesia chrome brick, magnetite chrome brick, magnetite, dolomite brick, forsterite bricks etc. mainly used for basic steelmaking furnace, smelting furnace for non-ferrous metal and cement kiln etc.