SU947211A1 - Method for converting lead-containing copper mattes - Google Patents

Description

This invention relates to non-ferrous metallurgy, in particular, to the technology for converting copper-lead mattes.

The closest to the technical essence and the achieved effect to the proposed is a method of converting lead-containing copper mattes, including purging them in the first and second converting periods with oxidizing gas, feeding quartz ore, limestone and circulating slags 11.

However, the known method does not allow lead to be sufficiently fully converted into sublimates during the processing of copper mattes with an elevated lead content (6-10%), and, moreover, the recovery of copper into the rough metal and the quality of blister copper do not improve.

The purpose of the invention is to increase the degree of sublimation of lead, antimony and mouse from the converter mass, increase copper recovery and improve the quality of blister copper.

The aim of the goal is achieved by the fact that in the known method of converting mattes, including blowing

their oxidizing gas in the first and second conversion periods, the supply of quartz ore, limestone and circulating slag, in the first period for each batch of matte after feeding the mixture of quartz ore and limestone in the melt serves sour pyrite concentrate in the amount of 50-80 kg per 1 ton matte with a speed of 900-1200 kg / min.

When it forms in the second period of slag conversion, it is supplied with pyrite concentrate in the amount of 80-120 kg per 1 ton of slag.

The method is carried out as follows.

Claims (3)

Pyrite concentrate is additionally supplied also in the case of pouring circulating slags in the first period, including slags from the anode furnace and slags from the second conversion period. In the second conversion period, in the case of obtaining converter-and-varnish 10-15 minutes before it is drained, a portion of the fluxes and pyrite concentrates are fed to the converter. The consumption of pyrite concentrate is 80-120 kg per 1 ton of slag, both in the case of loading on circulating slags in the first period, and when loading on slag in the second stage of the process. When supplying pyrite concentrate B and converter B to the melt, the reactions of the interaction of eurocium silicates with iron sulfides and sulfur occur as a result of pyrite dissociation. Lead sulfide is formed as a result of these reactions. Sulfidironium reactions of oxides mb, di, arsenic, and the destruction of magnetite occur in the melt as well. The resulting lead, arsenic, and antimony sulfides have higher vapor pressures at conversion temperatures compared to oxides and are distilled off with gases. Copper sulphide passes into the matte phase from the converter slag, which increases the extraction of copper into the draft metal. In addition, in the interaction of iron sulfides with components of the converter slag, as well as due to the dissociation of pyrite and the oxidation of sulfur, sulfurous anhydride is formed and its content in process gases increases. Reducing the consumption of pyrite concentrate below 50 kg per 1 ton of matte leads to a decrease in the degree of sublimation of lead, arsenal and antimony impurities due to incomplete sulfidization of oxides, and an increase in consumption of more than 80 kg per 1 ton of matte is undesirable due to a significant increase in the conversion process, a decrease in productivity and increase the output of the converter slats. The consumption of pyrite sulphurous concentrate per 1 ton of recycled slag and slag of the second conversion period, which is 80-120 kg / t, are also determined by the sulfidation conditions of lead, arsenic and antimony oxides contained in the slag, the degree of sublimation of these impurities and the amount of slag produced. . The feed rate of pyrite concentrate (900-1200 kg / min) into the melt is limited by the duration of the process and the thermal regime of the converter. Reducing the flow rate (less than 900 kg / min) leads to a significant increase (the duration of the process and a decrease in converter capacity. Increasing the flow rate (more than 1200 kg / min) can lead to supercooling of the spacing in the converter and disruption of the process mode. Example, To the 80 t converter 3 buckets of matte (54 tons) of the following composition are poured,%: copper, 5 2.1, lead 6.47, iron 12.6. When air is blown over the surface of the matte, a mixture of 85% quartz ore and 15% limestone in the amount of 250 kg per 1 ton of matte. Then melt the converter mass A pyrite (high-sulfur) concentrate containing,%: copper 0.4; iron 33.0; sulfur 38; calcium oxide 1.2; quartz 18 is supplied. The consumption of pyrite concentrate is 1100 kg / min at a rate of 50 kg per tonne of matte. After processing the loaded portion of matte, the converter slag is poured and the next matte bucket is poured (up to 6 buckets in total). New matte portions are processed similarly to the first one (matte filling, flux loading, pyrite concentrate feed, slag discharge). In the first period, the recycle slag of the second period and slag from the anode furnace are also charged. After loading circulating materials, pyrite concentrate is additionally supplied in the amount of 100 kg per 1 ton of circulating slag and the converter mass is treated with air blast. In the second conversion period, a regiment of recirculating slag is obtained. Fifteen minutes before the circulating slag is drained, fluxes and 1000 kg of pyrite concentrate are loaded onto its surface. Next, the converter mass is processed to produce blister copper. As a result of pilot melting, converter slag of the first period of the following composition is obtained,%: copper 3.00; lead 5.56; iron 29.3; silicon oxide 26.9, etc. The converter slag of the first period is circulating and is poured into an electric furnace for smelting concentrates. Chernov copper when converting matte with the addition of pyrite concentrate contains,% copper 99.18; lead 0.14; mouse 0.048; antimony 0.013. In the first period, the process gases of the converter contain on average 6.3% of sulfurous anhydride and are sent for dust collection in cyclones. The converter P7dsh selected in the flue contains 15.3% lead. When processing mattes of a similar composition according to the existing plant technology without supplying pyrite concentrate, the following results were obtained. Converter slags contain,%: copper 3,44; lead 6.41; iron 29.5; silica 26.0. Chernov copper contains,%: copper 99.01; lead 0.21; mouse 0.065; antimony 0.017. Converter dust contains 7.1% lead. Gases of the first period contain an average of 4.0% sulfur dioxide. The distribution of lead, arsenic and antimony compiled on the basis of the material balance shows that the degree of sublimation of lead according to the proposed method increases by 20–25% (relative), the mouse and antimony by 15–20%. A comparison of the conversion rates suggests that the method improves the degree of distillation of lead, arsenic and antimony from the converter mass, and improves the quality of blister copper. In addition, copper converter slag is depleted, valuable components are additionally extracted from pyrite concentrate, and the concentration of sulfur dioxide in the conversion gas is increased by 2-3%. When fed into the converter, pyrite concentrate in circulating converter slags is reduced by 1.5 times the magnetite content, which improves the performance of electric heating of copper concentrates. Claim 1. Method for converting swine-containing copper mattes, including purging them with oxidizing gas in the first and second conversion periods, feeding quartz ore, limestone and recycled slags, in order to increase the degree of sublimation of lead, antimony and mouse ka from the converter mass, increasing copper recovery and improving the quality of blister copper, in the first period, for each batch of matte, after feeding the mixture of quartz ore and limestone, high-sulfur concentrate is fed to the melt in the amount of 50-80 1 ton matte at a rate of 900-1200 kg / min. 2. Method POP1, characterized in that when a slag is formed in the second period of conversion, pyrite concentrate is supplied to it. 3. The method according to claim 2, which is also distinguished by the fact that the pyrite concentrate is fed in an amount of 80-120 kg per 1 ton of slag. Sources of information taken into account during the examination 1. USSR Author's Certificate No. 673664, cl. From 22 to 15/06, 1977.