Method for extracting metals from concentrated sulphurated minerals containing metals by direct reduction with regeneration and recycling of the reducing agent, iron, and of the flux, sodium carbonate

Abstract

A method is disclosed for extracting metals from concentrated sulphurated minerals containing metals by direct reduction with regeneration and recycling of the reducing agent, iron, and of the flux, sodium carbonate. It is a combination of pyrometallurgical and hydrometallurgical processes which differ from the conventional processes. They do not require previous toasting of the concentrated sulphurated minerals and are technically and economically more advantageous than the presently used processes, since they directly reduce to zero the positive oxidation state of the metal, using a single reactor for extracting the metal, regenerating and recycling the metallurgical feed materials in complementary processes, the kinetics of the chemical reactions being characterised by high speed, without generating any slags or pollutant gases. The metals can be extracted at a reduced cost and in an environmentally sustainable manner

Description

TECHNICAL FIELD[0001]The technical field relevant to apply the developed invention is mining and metallurgy, since it allows extracting ferrous and non-ferrous metals from sulphurated minerals bearing them by applying an improved direct reduction process, with no emissions of sulphur dioxide and without producing slag, which is commonly produced by conventional pyrometallurgical plants, thus minimizing environmental pollution. In addition, through the proposed regeneration and recycling of iron as reducing agent and sodium carbonate as flux, the operating costs of the process are substantially reduced.STATE OF THE ART (OR BACKGROUND OF INVENTION)[0002]According to Aranguren F & Mallol A. (1), several metallurgical reduction processes were known and applied for some time in metal extraction activities. Among them, the reduction of iron oxide minerals (mainly, hematite and magnetite) stands out for its relevance, since it allows to obtain pig iron or direct-reduced iron, metallurgical...

AI Technical Summary

Benefits of technology

The patent is about a new technology that can extract minerals like iron, lead, zinc, copper, molybdenum, antimony, arsenic, and gold from sulfur-containing minerals without emitting sulfur dioxide or producing slags. The process also reduces operating costs by recycling iron and sodium carbonate as reducing agents and flux. Additionally, the patent proposes the economic recovery of valuable minerals from the tailings of mining concentration plants, which can provide economic benefits and also contribute to the production of metallic iron, a valuable commercial product.

Problems solved by technology

One of the characteristics of the plants implementing these latest processes is the large amount of emissions of sulphur dioxide they generate, forcing them to install expensive sulphuric acid manufacturing plants to minimize environmental pollution, as well as great amounts of slag, which are stockpiled near the metallurgical plants, polluting the environment in the area of influence.

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