Method and plant for producing iron from roasted pyrites

A method for obtaining at least one of metallic iron and iron chloride from ores or ore residues in the form of pyrite residues,

• wherein the method comprises the following steps (a) to (d), wherein the below-indicated steps (a) to (d) are carried out in the order listed hereinafter:
• (a) providing a starting material in the form of at least one ore or ore residue,
• wherein the starting material comprises:
• (i) iron,
• (ii) at least one noble metal selected from the group consisting of gold, silver, and combinations thereof, and also
• (iii) at least one further metal selected from the group consisting of copper, zinc, lead, cobalt, titanium, manganese, vanadium, chromium and combinations thereof;
• (b) oxidation treatment comprising calcining and oxidative roasting of the starting material in the presence of at least one oxidizing agent to form oxidation products including iron oxide and oxides of the further metals;
• (c) chlorination of the oxidation products obtained in step (b) using at least one recyclable chlorinating agent, comprising the chlorination of iron oxide and oxides of the further metals to form a product mixture including iron chloride and chlorides of the further metals;
• (d) selectively removing of the iron chloride from the product mixture obtained in step (c) and subsequently removing of the chlorides of the further metals from the product mixture freed from iron chloride, wherein the selectively removing of iron chloride takes place by sublimation of the iron chloride, wherein the iron chloride selectively removed in this way is obtained as such by subsequent desublimation, or wherein, alternatively, the iron chloride selectively removed is subjected to reduction to form metallic iron;
• wherein in step (c) the chlorination is carried out as a solid phase reaction and using ammonium chloride (NH4CI) as chlorinating agent,
• wherein the ammonium chloride in step (c) is recycled by recovery of ammonia (NH3) resulting from the chlorinating agent in the chlorination of the oxidation products and subsequent reaction of the ammonia with hydrogen chloride (HCI) and
• wherein the recycling of the ammonium chloride is carried out in a reaction- or condensation-device.