Aluminum will produce ash, which is inevitable product of melting. The aluminum ash is made of alumina, aluminum nitride, other oxides, chlorides and aluminum. If this product is not handled properly, it will cause many problems.
First, the economic benefits of the recycled aluminum industry.
The amount of aluminum contained in the aluminum slag just removed from the furnace is 45% to 75%. Since the amount of aluminum slag is about 15% of the amount melted in the furnace, how to increase the amount of aluminum recovered from the aluminum slag is a matter of regeneration Aluminum industry, is an important issue. In other words, if the ash handling is not good, it will directly affect the economic benefits of recycled aluminum industry.
Second, the impact on the cost of recycled aluminum products.
Taking the factory with monthly melting capacity of 3000t as an example, aluminum slag production can be up to 450t, aluminum content of 202.5 ~ 337.5t. The aluminum recovery rate is 45%, aluminum recovery is 90 ~ 152t; if the recovery rate is 70%, the recovery of aluminum up to 142 ~ 236t, a difference of 52 ~ 84t, the difference is equivalent to gross margin of 2% to 3%.
However, if recycling the aluminum from aluminum ash, the higher of recovery rate, the more difficult it will be, that is, even if it can be recovered to 70%, the remaining residue is difficult to handle, aluminum 30% aluminum can be used as steelmaking deoxidizer. As a result, most recycled aluminium extrusion manufacturers now avoid over-reclaiming from aluminum and aluminum slags, but instead sell the aluminum sludges to aluminum dross or steel-making deoxidizers. Therefore, the recovery rate of aluminum ash has a direct impact on the cost of recycled aluminum products.
