Build a furnace
The main aluminum refractory material is high-alumina brick masonry. Three layers of graphite carbon bricks are built on the bottom of the furnace, and one layer of graphite carbon bricks are built on the walls of the furnace. A layer of electrode paste is knotted at the bottom of the furnace before starting the furnace, with an average thickness of 200mm.
Raw material preparation
Bauxite
Content: AL2O3 55%-90% SIO2 20%-30%.
Granularity: 30-120mm Rinse clean
bituminous coal
Compared with other alloys, silicon-aluminum-iron alloy smelting is the most unique in the application of the original agent. Among the reducing agents used, bituminous coal accounts for more than 80%.
Composition: 15%-25% volatile, less than 20% ash, less than 55% fixed carbon, good slagging performance.
Silica
In fact, the normal smelting of silicon-aluminum-ferroalloy does not have high requirements for silica. We have used it from 90% to 99% of the SiO2 content, and even used over-mature silica, which does not have a great impact on the smelting. Except for special circumstances, generally more than 95% of silica can be used. However, there are still strict requirements when opening the furnace: SiO2 is greater than 98%, good anti-explosion, cleaned, and the particle size is below 100mm.
Iron bauxite
This kind of raw material is indispensable in our smelting experiment, and it has a certain catalytic effect on the reduction of aluminum during the entire smelting process.
Ingredients
The ingredients for furnace smelting should consider factors such as low furnace temperature, and the ferrosilicon furnace can be used to open the furnace and then switch to smelting ferrosilicon and aluminum. However, we all use direct smelting of silicon, aluminum and iron. The raw material batch is based on the 25% aluminum content and 35% silicon content of the baked product. Carbon-rich operation is required when the furnace is opened. According to different raw materials, accurate batches cannot be given here.