With the rapid development of China's glass industry, China has become the world's largest glass-producing country. The rapid development of the glass industry has naturally contributed to the development and technological upgrading of refractory materials for glass kilns in my country. Compared with the traditional technology, the modern glass technology production technology has made more than a little progress, and it has continued to develop in the direction of higher efficiency, lower power consumption and better product quality. As the central equipment for glass production, the technical level of the kiln is constantly improving, and new technologies such as increasing the incineration intensity, strengthening the heat transfer effect, reducing the heat loss, and reducing the pollution to the product and the environment are widely used. The technical improvement of kilns requires a variety of high-quality refractory materials as important conditions to ensure that refractory materials can accept higher temperatures, more rapid temperature changes, more intense chemical corrosion, and more severe stress damage. As long as the supporting applications are more,the variety of high-quality refractory materials, the high efficiency, energy saving, and low pollution of the new kiln skills will be reflected. High-quality refractory materials are not only expensive materials for modern high-temperature technologies, but also functional materials necessary to complete new high-temperature technologies.
1.AZS and high zirconia bricks
The main purpose of fused AZS brick is to improve its corrosion resistance and abrasion resistance production process. In addition to adopting oxidation method to melt, the carbon content of the product is reduced to 0.005, and the glass phase separation temperature is increased to 1450 ℃. The casting and annealing process has also been improved, and the fused AZS with small shrinkage cavity volume or even no shrinkage cavity has been produced. High zirconia bricks with a ZrO2 content of more than 90 have a very good thermal shock function, such as ZrO295, SiO21.4. High zirconia brick with stabilizer 3.7, bulk density 4.7g/cm3, porosity 18.4, thermal shock resistance from room temperature to 1400°C (15 minutes distance) up to 15-20 times. Japan produced a fused-cast zirconia brick with a zirconia content of 90, which is called ZFC brick. Its corrosion resistance is better than that of AZS bricks with a ZrO2 content of 40. There is no glass phase separation after 16 hours at 1500—1600°C. Out, there is very little pollution to the glass, and there is no crack after 40 times of thermal shock resistance test at 800-1250℃.
2. Chrome bricks and chrome bricks
The fine chromium oxide bricks formed by isostatic pressing are used on the side walls, necks or other severely corroded parts of E glass and C glass tank kilns, and the life span can reach 6-7 years. In recent years, chromium-containing products have made new progress. For example, in AZS bricks, Cr2O3 is used to form Al2O3-ZrO2-SiO2-Cr2O3 refractory materials. At high temperatures, Cr2O3 forms a solid solution with Al2O3 on the one hand, and on the other hand, because Cr2O3 is High melting point substances entering the glass phase of the brick increase the viscosity of the glass phase, thereby increasing the exudation temperature of the glass phase, and greatly improving the glass corrosion resistance of glass products. A company in the United States has produced a recombination fused cast AZS/Cr2O3 refractory, which has superior chemical composition and physical functions. Compared with the original Al2O3/Cr2O3 material, the electricity consumption per year is reduced by 4, the output value is increased by 15, and the cost is reduced. 3.75. The quality of the glass is not affected. This kind of brick can be formed by machine pressing, manual ramming or isostatic pressing, and then sintered at high temperature.
3. Alkaline Brick
High-purity direct-bonded alkaline bricks fired at 1800°C are widely used in regenerator walls and sills. Germany has launched a new material, the product name is RUBINAIEZ, and its chemical composition is MgO75, ZrO23.5, and SiO29.5. It is a periclase brick combined with zircon. In the early stage of sintering, the zirconium silicate in the brick structure reacts with magnesia, forming a protective layer of forsterite and zirconia along the periclase particles. This structure is greatly improved It has the alkali resistance and sulfate resistance corrosion function of the brick, and it has an excellent effect as a checker brick in the middle of the regenerator.
4. Olivine Magnesia Brick
Olivine binding phase has a particularly strong anti-corrosion function. By increasing the content of forsterite in the binding phase of magnesia bricks, the corrosion resistance of magnesia bricks can be improved. For this reason, 20 forsterite fine powder is added to the ingredients of magnesia bricks to form a forsterite binding matrix that can protect magnesia particles and reduce corrosion. The price of the brick is relatively cheap, and many foreign countries have been used in the middle of the grid body of the regenerator of the glass kiln.
5. Feldspar olivine brick
In view of the good corrosion resistance of olivine, but the insufficient thermal shock resistance, the introduction of barium feldspar in its combination can significantly improve the thermal shock resistance of the brick. The feldspar is formed during the firing process and only exists in the binding matrix phase. When the content of feldspar is 15, the function of silicon is very good, and the operating temperature is about 1250°C. Studies have shown that barium feldspar can resist alkali and sulfate corrosion.
6. Unshaped refractory
The application of monolithic refractories in glass kilns is also a kind of development momentum. The British use refractory concrete prefabricated blocks to build the regenerator, checker brick bottom chute, flue, small furnace pallet, burner, etc., which greatly reduces the joints of the kiln structure, significantly speeds up the furnace construction and shortens the cold repair At the moment, France's ERSOL is an unshaped refractory series made of ER1681 fused particles as the main component. It is used in the bottom of the pool with fused bricks. It has excellent glass corrosion resistance, and separates bubbles and formation stones. The tendency is weaker. Some Japanese glass kiln bottoms have all used ER2SOL series of indeterminate materials. The theoretical research on refractory materials used in foreign glass kilns is focused on how to further improve the corrosion resistance of glass and improve the mechanical function, in order to further extend the life of the kiln.
