Hot air baking technology

As we all know, for a glass production enterprise, the melting furnace is the heart of the enterprise. The invention of hot air baking technology is of great significance for prolonging the service life of the furnace and improving the output and quality of glass products.

With the development of glass industry technology, the life of glass furnaces is generally prolonged, and the heat utilization rate and glass quality are significantly improved, which is related to the improvement of refractory quality and the emergence of new varieties of refractory materials. In particular, it is closely related to the development of electric melting refractories in the last century. Because the fused refractory has high density, wear resistance, good high-temperature mechanical properties and corrosion resistance of molten glass, the important parts of the glass melting furnace are replaced by fused zirconia corundum bricks at present.

In western industrialized countries, with the progress of material science, the development of baking technology and temperature control means, the over-fire temperature of glass melting furnace has risen to 1100-1150℃. In this temperature range, the refractories in all parts of the furnace have basically completed the crystal transformation and are in a stable stage. At this time, the over-fire is easy to connect with the temperature after the over-fire, which will not cause great fluctuation, thus preventing the explosion of electric melting bricks and laying a good foundation for the safe operation of the furnace. At present, the service life of glass furnaces in developed countries is generally more than 10 years, and high temperature baking is one of the important factors. In China, the service life of glass melting furnaces has also been significantly improved in recent years, from the previous 3-4 years to 6-8 years. At present, the planned kiln life of newly designed glass production lines in China is more than ten years, which is inseparable from the improvement of refractory quality, the improvement of furnace structure and masonry quality and the reasonable operation and use, and we can't ignore the high-quality preheating work of baking kiln. In the development process of domestic glass industry, there are many cases in which unreasonable baking kilns leave potential safety hazards, resulting in kiln accidents or even early water release, which have attracted great attention of technicians and senior managers of glass production enterprises. However, due to various reasons, domestic glass production enterprises rarely choose high temperature and excessive fire in the construction of new kilns or cold-repaired kilns. There are two reasons:

First, it is hard to find a professional baking kiln team that can reach over 1100℃ in China. High temperature and excessive fire require not only superb professional technology, but also advanced and excellent equipment support. At present, there is still a certain gap between the equipment level of most domestic professional kiln enterprises and that of developed countries. First, the ability to raise and control the temperature is limited, and the ability of materials and equipment to resist high temperature is limited. For example, the burner flame tube in China usually turns around when the temperature is above 900℃, and the temperature naturally cannot go up. Therefore, for a long time, domestic joint ventures or wholly-owned glass enterprises have been paying high prices to hire foreign kiln companies to bake and bake.

Second, for the sake of short-term economic interests. Compared with the traditional fire at 850℃, the high-temperature fire requires higher energy consumption and longer heating time. For example, compared with the fire at 850℃, the fire at 1150℃ in a furnace with a melting capacity of 500t/d needs 80-100 tons more diesel oil, and the fire at 850℃ needs about 100-120 tons of heavy oil to heat up to 1150℃. Calculate the difference, 1150. However, the cost of 100,000 yuan is relative to the million or even ten million overhaul expenses caused by the hidden dangers left by unreasonable low-temperature overheating; 3-5 days compared with the 1-2 years kiln life extended by high temperature and excessive fire, how will our enterprise managers choose?

In the past two years, the construction of new glass production lines and the cold repair of old lines in China have entered the peak period. We suggest that qualified glass enterprises, especially large-scale float kilns, choose the scheme of high temperature and excessive fire as much as possible when igniting and baking kilns. You know, today's contribution is tomorrow's kiln age and quality.