Can the iron and the magnesium contained in CGI be separated when the iron is scrapped? If not, can the CGI be recycled?


Shareholder, name withheld

The magnesium contained in CGI is dissolved, in much the same way that sugar is dissolved in hot coffee. The total amount of magnesium in CGI is approximately 0.01%, or equivalently, about 10 grams in a 100 kg CGI casting.

In order to recycle cast iron, it must be melted at approximately 1500 degrees Celsius. Because the boiling point of magnesium is only 1089 degrees Celsius, it simply evaporates from the molten iron. There is no contamination at all. In fact, this is one of the main environmental advantages of iron and steel. Iron and steel can be continuously recycled with no degradation of their properties. The average ’piece’ of iron that our shareholders see in their everyday lives has already been used seventeen times before as a different product. The comparable statistic for aluminium is less than three cycles. Also, the properties of aluminium degrade slightly with each new product cycle, primarily due to the accumulation of undesirable chemical elements.