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What are the unique product characteristics of zirconium corundum brick

Release time:

2021-11-09 10:29

There are five kinds of raw materials for zirconium corundum refractory bricks: alumina, zircon sand, zirconium-rich sand, soda ash and foundry sand.

1) The introduction of alumina is generally made of industrial alumina. The production requires that the water content should be less than 0.3 and the loss on ignition should be less than 15%. One ton of AZS -33 fused brick needs about 0.62 tons of alumina.

2) Zircon sand mainly causes dyeing of AZS products, causing coarse crystal sand holes and affecting cracking at the same time. Therefore, its content should be less than 0.2, which affects cracking of castings during cooling and also affects the oxidation process of products. Therefore, its content should be less than 2%, and about 0.65 zircon sand is required for each ton of AZS -33 electrofused bricks.

3) Zirconium-rich sand is also called desilication dry. The silica in AZS all comes from zircon, and the insufficient part is supplemented by zirconium-rich sand.

4) Sodium oxide is introduced into soda ash as a flux for AZS bricks. Generally, secondary products are used. One ton of AZS -33 electric melting bricks needs about 2Okg pure city.

5) Borax is also a flux for AZS bricks. A ton of AZS -33 electric melting bricks requires about 2Okg borax.

Application of fused corundum brick in float glass melting furnace

The glass melting furnace is a thermal equipment for melting glass composed of refractory materials. The service efficiency and service life of glass melting furnace depend on the variety and quality of refractory materials to a great extent. The development of glass production technology depends to a large extent on the improvement of refractory manufacturing technology. Therefore, the rational selection and use of refractory materials is a very important content in the design of glass melting furnaces. To do this, we must master the following two points, one is the characteristics and applicable parts of the selected refractory materials, and the other is the use conditions and erosion mechanism of each part of the glass furnace.

Process Improvement of Electro-fused Zirconium Corundum Pavement Brick

Electrically fused zirconium corundum brick is made of industrial alumina powder and zircon sand (containing 66% of zirconium oxide and 34% of silicon dioxide) melted at high temperature in an electric furnace. After melting, it is cast into a shape (the casting temperature is 1780-1840 ℃), injected into the model and cooled to form a solid close to white. Its petrographic structure consists of the eutectoid body and glass phase of corundum and zirconium clinite, it is a eutectoid body of corundum phase and zirconium clinoptilite phase, and the glass phase is filled between their crystals.

How to overcome the defects produced in the casting and annealing of fused zirconium corundum bricks

Electrofused zircon corundum brick in the production will produce a variety of defects, resulting in the use of poor quality products. The physical and chemical inhomogeneity of zirconium corundum bricks is often the main reason for the defects of the products. Particles that are not melted through in the batch and gas inclusions that have not been discharged from the melt in time are all physical inhomogeneities. The difference in the composition of the melt along the depth of the furnace is a chemical inhomogeneity.

Causes of Serious Erosion of Zirconium Corundum Brick in Glass Electric Melting Furnace

The erosion of fused zirconium corundum brick is mainly divided into physical action and chemical action. Physical action refers to the glass melting furnace wall in the long-term operation process, repeatedly subjected to the impact of rapid cooling and rapid heat, the surface must undergo a contraction of the expansion of the change process. Due to excessive fatigue, the structure of fused zirconium corundum brick is damaged, resulting in increased surface cracks and loose structure. Therefore, under the action of air flow, material and glass liquid washing, cracking and peeling, and this process will be repeated.