Analysis of classification and application of refractory clay

Refractory clay is divided into soft clay, semi-soft clay, hard clay and high-alumina clay according to plasticity, ore characteristics and industrial use. Soft clay is generally in the form of soil, which is easy to disperse in water, and can form plastic sludge after mixing with liquid; semi-soft clay has poor dispersibility, and its mixed part can also form plastic sludge after mixing with liquid . These two kinds of clays are often used as binders when making refractory products. Hard clay is often in the form of lumps or slabs, generally does not disperse in water, and has high refractoriness. It is the main raw material for refractory products. The high-aluminum clay has a high content of Al2O3, a large hardness and a specific gravity, and a high degree of refractoriness. It is commonly used to manufacture high-grade clay products.

 

Refractory clay is mainly used in the metallurgical industry, as a raw material for the production of shaped refractory materials (bricks of various specifications) and unshaped refractory materials, the amount of which accounts for about 70% of all refractory materials. The hard clay in refractory clay is used to make blast furnace refractory materials, iron making furnace, hot air furnace, brick lining brick and plug brick. High-alumina clay is used to make aluminum bricks, high-alumina lining bricks and high-alumina refractory mud for electric furnaces and blast furnaces. Hard clay and high-alumina clay are often used in calcined mature materials at high temperature (1400 ～ 1800 ℃).

Aluminum refractory bricks, high-alumina fused cast bricks. The high-alumina clay is calcined, and then mixed with limestone to make aluminum-containing cement. This cement has the characteristics of quick setting ability, corrosion resistance and strong heat resistance.

 

Refractory clay also has important uses in the grinding industry, chemical industry, and ceramic industry. High-alumina clay is melted in an electric arc furnace to produce abrasive materials. Among them, fused corundum abrasive is currently the most widely used abrasive, accounting for 2/3 of all abrasive products. High alumina clay can be used to produce various aluminum compounds, such as aluminum sulfate, aluminum hydroxide, aluminum chloride, potassium aluminum sulfate and other chemical products. In the ceramic industry, hard clay and semi-hard clay can be used as raw materials for the manufacture of daily-use ceramics, architectural porcelain and industrial porcelain.

 

In addition, high-alumina clay is also used in oil wells, as a proppant for purifying petroleum, as a fertilizer promoter in agriculture, and as a paving material for anti-slip and anti-wear, etc. Hard clay is also used to make a new type of refractory insulation material-refractory fiber, which has the advantages of high temperature resistance, small thermal conductivity, acid and alkali resistance, sound absorption and light weight. It is used in metallurgy, machinery, electronics, glass, ceramics and other industries widely.