Method for processing red muds

摘要

A method of recovering metal and slag from red mud by adding a carbonaceous reducing agent and sand with limestone or dolomite to the red mud to form a burden which comprises 3.5-5.5 weight % carbon and having a weight ratio of silica:calcia lying in the range 1.3-1.5:1. The burden is heated to a temperature in the range 1690-1790 0C where it is molten and forms slag and metal phases. The slag is poured into water with a copper sulphate concentration in the range 0.3-0.5 g/L where it foams, while the metal is poured into moulds. The carbonaceous reducing agent reduces the ferric oxide and titanium oxide to form an iron-silicon-titanium-carbon alloy. The carbonaceous material is preferably anthracite although charcoal, brown coal and coke are also disclosed. The burden is preferably heated at rate of 16-18 0C/min.