RU2324751C2 - Processing method of raw materials containing non-ferrous metals and iron - Google Patents

Abstract

FIELD: metallurgy of non-ferrous metals.

SUBSTANCE: invention pertains to the metallurgical industry, predominantly to the metallurgy of nickel and cobalt. It concerns procurement methods of liquid metals with reprocessing of an oxygenized, metal-containing natural raw material and technogenic materials. This method works in the follow manner: the melted slag of a fusion mixture, consisting of initial material, flux agent, liquid and firm slag, carbon-containing material and oxygen in an oxygen-containing forced draught, is introduced into an oxygenized area of the twin-chambered furnace. The fusion mixture must be provided in appropriate quantities that would guarantee complete burning of carbon and the highest heat emission. Thereafter a fusion of slag is performed, resulting in the liquid slag formed. The product is then introduced into the recreation area along with the carbon-containing material, oxygenated draught and additional fluxes in such quantities as deemed sufficient to, firstly, restore oxides of obtained metals in the metal phase and, secondly, to indemnify for the lost thermal expenses. The relations between expenses of an oxygenated material per ton of the obtained material in the oxidative and restorative areas must be maintained within the 0.3-2.5 range, and a specific oxygen consumption rate in these areas should be preserved within the range of 0.7-3.0. Periodically, prior to an emission of the metal component of the fused products in the slag siphon, it is heated with an electric arc at the border between the sintered and metal baths until the 1350 - 1500°C range of temperatures is finally reached. Before emitting of the metal component, the molten mass must be kept still for some 10 to 15 minutes while electricity has to be switched off on electrodes. The technical result of this process increases extraction of metals and is a significant improvement of division between the sintered and metal baths.

EFFECT: improvement of the metal extraction when the raw materials, containing non-ferrous metals and iron, are reprocessed.

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Description

The invention relates to the field of metallurgy and relates to methods for producing liquid metal in the processing of oxidized metal-containing natural raw materials and industrial materials. The invention can be used for the production of nickel, copper and iron.

A known method of continuous processing of raw materials containing non-ferrous metals and iron, in particular the production of ferronickel or nickel matte from oxidized nickel ores (RF patent for the invention No. 2194781, publ. 12/20/2002 bull. No. 35).

The method includes feeding a mixture consisting of feedstock, fluxes, liquid or solid processed slag, carbon-containing material and oxygen in an oxygen-containing blast in the amounts necessary for complete combustion of carbon with maximum heat release, melting the mixture with the formation liquid slag entering the reduction zone, into which carbon-containing material, oxygen-containing blast and additional fluxes are supplied in quantities necessary For the reduction of oxides of recoverable metals into the metal phase and compensation of heat costs, maintaining the ratio of the consumption of carbon-containing material per ton of recoverable metal in the oxidation and reduction zones within 0.3–2.5, and the specific oxygen consumption in these zones within 0.7– 3.0, release of smelting products from the reduction zone of the furnace.

The disadvantages of this method are:

- the formation of a heterogeneous intermediate layer at the border of the slag and metal baths with a decrease in temperature in the tuyere zone, which complicates the separation of slag and metal;

- when the fuel supply is stopped, the blast quickly cools the melt, it may froth first and then freeze.

The technical result of the proposed method is to increase the extraction of metals in matte (ferroalloy) due to their additional recovery and improved separation of slag and metal phases.

The proposed method is characterized in that before the release of the metal phase of the melting products, the melt in the slag siphon is periodically heated by an electric arc. An arc is formed at the slag-metal phase boundary, with additional reduction of metals in the metal phase due to the consumption of graphite electrodes. There is also a depletion of slag due to mixing of the melt with an arc and an increase in temperature, followed by sedimentation of the melt before the discharge of the metal phase.

Example. Oxidized nickel ore containing 1.07% Ni is processed; 24% Fe; 48% SiO ₂ . 41.7 t / h of ore with a moisture content of 10% are charged into the oxidation zone; 12.8 t / h of limestone; 7.4 t / h of coal; 9740 nm ³ / hour of technical oxygen; 2300 nm ³ / hour of air.

In the recovery zone load 2 t / h of coal; 1.3 t / h of sulfur pyrite; 1500 nm ³ / hour of oxygen and 800 nm ³ / hour of air into the melt and 760 nm ³ / hour of oxygen and 300 nm ³ / hour of air for afterburning.

Before the discharge of the metal phase, a direct current is supplied to the slag siphon through graphite electrodes. The melt in the siphon is heated to a temperature of 1350-1500 ° C, after which the voltage at the electrodes is turned off. The metal phase is left to drain for 10-15 minutes.

The output of the metal phase is 2 t / h, which is 0.2 t / h higher than in the known method.

Claims (1)

A method of processing raw materials containing non-ferrous metals and iron, comprising supplying a mixture of raw materials, fluxes, liquid or solid processed slag, carbon-containing material and oxygen in an oxygen-containing blast to the oxidizing zone, in quantities necessary for complete combustion of carbon, melting the mixture to form liquid slag entering the reduction zone into which carbon-containing material, oxygen in an oxygen-containing blast and additional fluxes in quantities are required x for the recovery of oxides of recoverable metals into the metal phase and compensation of heat costs, while maintaining the consumption of carbon-containing material per ton of recoverable metal in the oxidation and reduction zones from 0.3 to 2.5 tons, and oxygen in the blast in these areas from 0.7 to 3.0 nm ³ and an outlet melt fusion products, characterized in that the periodically before the release of the metal phase product melting slag melt in the siphon heat by an electric arc at the interface of the slag and metal phases to a temperature from 1350 to 1500 ° C, etc. than the melt in the siphon before the release of the metal phase defend from 10 to 15 minutes at power off at the electrodes.