Reuse of products from waste anodes of aluminium smelter

This study aims to assess the presence of fluorine in products (concentrates and tailings) of selective froth flotation of materials resulting from demolition of electrolytic cells used in aluminium electromining. In fact in a previous work (Ciccu et al. 2009) the possibility of recovering a combustible matter from this wastes using froth flotation has been studied. In particular the following aspects have been evaluated: · The relationship between F and C contents in flotation products · The need to reduce the content of F in the concentrates for use them as fuels in accordance with the current national and international laws · The convenience to reduce the content of F in the flotation tailings destined to waste deposits. The levels of F assessed in the products suggest to consider the possibility of recovering this element as by-product to be used in the cement industry. The results show that the presence of F in the products of froth flotation, although being a penalizing element, does not preclude the recovery of this material to be used as fuel, especially if appropriate precautions are taken.