Refractory ball for regenerator
There are mainly 3 kinds of refractory balls used in the high temperature area of the ball bed:
1. High aluminum refractory ball
Al2O3 mass fraction is greater than 45%, to alumina or aluminosilicate based refractories are called high alumina refractories. General high aluminum refractory ball refractoriness is not less than 1750-1790℃, the starting temperature of load softening is not less than 1400-1530℃. The higher the content of Al2O3, the lower the thermal stability.
The high alumina refractory ball is used in the high temperature area of the upper section of the ball bed in the production. The refractoriness and softening temperature under load can meet the requirements, but the thermal stability and slag resistance are insufficient. Therefore, surface cracks and slag bonding often occur, resulting in poor bed permeability and shortening of ball cleaning period.
2. Silicone refractory ball
Silica refractory ball is a kind of acid refractory material, the mass fraction of SiO2 is more than 93%, other components are mainly Al2O3, Fe2O3, CaO, MgO and some alkali metal oxides. The refractory degree of silicon refractory ball is generally 1710-1750℃, and the load softening temperature is higher, up to 1640-1650℃.
The silicon refractory ball is used in the high temperature area of the upper section of the ball bed in the production. Under the conditions of high temperature and large gradient temperature change, the surface of the ball is seriously cracked, and the ability of resisting alkali gas dust corrosion is poor, and the phenomenon of slag-bonding is serious, so it is difficult to clean the ball.
3. Magnesium aluminum refractory ball
The production process of magnesia-alumina refractory ball is finer and stricter than that of common magnesia-alumina refractory brick, and its performance is also better than that of common magnesia-alumina refractory products. Good thermal stability, 850℃ water heat exchange times can reach more than 20 times; Good slag resistance, especially the ability to resist Fe2O3 erosion is particularly high. Magnesium aluminum refractory ball is suitable for the high working temperature and frequent fluctuation of the upper section of the ball bed. Three kinds of refractory ball, magnesium aluminum refractory ball is conducive to the accumulation of heat and heat transfer, hot blast stove at the same time solve the problem of sticking the ball, and under the effect of long-term high temperature load, stable structure, catalysis and softening occurs with at present, in the period of high temperature ball bed, magnesium aluminum refractory ball casting replaced the other two, is used by more and more enterprises.
Since the use of ball hot blast stove, refractory balls have been made of common materials such as stone, clay, silicon, high aluminum and magnesium aluminum, etc., and now they have developed into high quality materials such as low creep, magnesium chromium and corundum series.
General high aluminum refractory ball, its refractory degree is not less than 1750-1790℃; The starting temperature of load softening is not lower than 1420-1500℃; Al2O3 belongs to amphoteric oxide, so the ability to resist acid slag erosion is better, but if the silicon refractory ball, alkaline slag erosion performance is also better, but if the rain magnesium aluminum refractory ball; The higher the content of Al2O3 in the product, the lower the thermal stability of the product. High alumina refractory ball is used in the high temperature area of the upper section of the ball bed. Its refractoriness and softening temperature under load are sufficient, but its thermal stability and slag resistance are insufficient. After practical application, surface crack and slag bonding often appear, resulting in the bed permeability is worse, the cleaning period is shortened.
Common magnesium aluminum ball type with magnesium oxide as the main component and contains alumina alkaline material, magnesium aluminum ball high density, high heat, heat storage capacity is strong, strong thermal conductivity, excellent slag resistance.