Pyrometallurgic process for the treatment of steelwork residues

摘要

A pyrometallurgic process for the treatment of post-steelwork residues, comprises the following phases: preparing a furnace (1) of the electric type, suitable for the introduction of the residues; preparing the residues, for example in a hopper with the possibility of mixing with additives and reaction elements; introducing the residues, together with suitable additives and chemical reagents, into the furnace (1); introducing directly into the slag, by means of lances (4), additives, flushing and reaction elements to correct the composition of the slag (7); reacting the residues with the slag (7) to obtain: a) separation of the liquid metallic phases which are added to the metal bath (6) to form a sellable liquid metal; b) separation of the metallic volatile elements in vapour phase which, when transferred to the free zone of the furnace (1), possibly with the help of post-combustion, recombine with the oxygen for the formation of oxides and consequently of powder; c) separation of the stable phases, typically ceramic and/or silicates, which form the inert phase of the slag (7); d) separation and neutralization of other elements risky for the environment present in the residues themselves to make the slag (7) inert; supplying energy by means of an electrode column (5) to the reaction bed or slag (7) to sustain the above reactions; extracting the metallic bath (6) and inert slag (7).