The life of an aluminium melting furnace depends largely on the quality of the refractory material. Refractories withstand high temperatures and molten aluminum erosion during the aluminium melting process, so their performance and life are crucial to the stable operation of the aluminium melting furnace. In order to ensure a long life and efficient operation of the kiln, there are several key factors to consider when selecting the right refractory material. When selecting refractories for aluminum-making furnaces, the influence of various factors such as the strength, porosity and porosity distribution of refractories, and the addition of anti-aluminum wetting agent should be considered.
1. Use raw materials with high erosion resistance
The importance of Al2O3 content in refractories to resist molten aluminum erosion has been proven in practice. In fact, as the Al2O3 content increases, the refractory becomes less reactive with the molten aluminum, which means that its resistance to molten aluminium penetration and erosion is enhanced. This is mainly because Al2O3 has a high melting point and chemical stability, which can effectively resist the erosion of molten aluminum, so it is required that the Al2O3 content of refractory materials used in the melting pool of aluminum melting furnace should be more than 75%.
In order to meet this requirement, the ratio and quality of raw materials need to be strictly controlled in the production process of refractory materials. In addition, the use of advanced preparation technology and optimized firing system are also key factors to ensure that the Al2O3 content reaches more than 75%.
2. Improve the anti-aluminum wetting performance of refractories
The effect of the permeability of molten aluminum on refractories is an issue that needs to be paid attention to. Due to the high permeability of molten aluminum, it is able to easily penetrate into the pores and crevices of the refractory, which can lead to the destruction and erosion of the refractory structure.
In order to ensure that the refractory material is not permeated by the molten aluminum, the first task is to solve the problem of the castable being wetted by the molten aluminum. Wettability refers to the ability of a liquid to adhere to a solid surface. If the molten aluminum is able to wet the surface of the refractory, then it can easily penetrate into the interior of the material. Therefore, to prevent the penetration and erosion of the refractory material by the molten aluminum, it is necessary to ensure that the castable is not wetted by the molten aluminum.
3. Reduce porosity
The lower the porosity of the refractory, the less likely the aluminum melt is to penetrate into the refractory interior, and thus the erosion of the refractory is reduced.
4. Improve the strength and thermal shock stability of refractories
In the process of melting aluminum, the feeding of aluminum ingots and scrap aluminum will impact the wall of the melt pool, and the slag scraper will also cause damage to the inner wall of the melt pool. In addition, frequent opening and closing of the furnace door can cause temperature fluctuations, which can cause thermal damage to the refractory. All of these factors accelerate the loss and deterioration of refractories. Therefore, it is particularly important to improve the strength and thermal shock stability of refractories in order to extend their service life.
When selecting refractories for aluminum-making furnaces, factors such as strength, porosity, pore distribution, and thermal stability should be comprehensively considered. Through the reasonable selection and use of high-quality refractory materials, the service life of the aluminum melting furnace can be effectively extended, and the production efficiency and economic benefits can be improved.